Process for roll-to-roll manufacture of a display by synchronized photolithographic exposure on a su

专利摘要:
The present invention relates to electrophoretic displays or liquid crystal displays, and to novel manufacturing processes thereof. The electrophoretic display (EPD) of the present invention has well-defined microphone cups filled with a liquid crystal composition having a typical reflectance at least that matches the reflectance of the isotropic cup material. The novel roll-to-roll method and apparatus of the present invention can perform display manufacturing continuously by a synchronized photolithographic process. Synchronized roll-to-roll methods and apparatus can rotate a pre-patterned photomask, formed as a continuous loop, by a synchronous movement aligned almost parallel to a web that was previously coated with a radiation sensitive material. The radiation sensitive material may be a radiation curable material, where the exposed and cured portions form a microcup structure. In an additional process step, the radiation sensitive material may be a photoresist that acts positively to temporarily seal the microcups. Exposure of the selected subset of microcups through the photomask image can selectively reopen, fill and seal the microphonecup subset. Additional colors can be repeated to continuously assemble a multicolor EPD or LCD display
公开号:KR20030091988A
申请号:KR10-2003-7010765
申请日:2002-02-14
公开日:2003-12-03
发明作者:메리 찬-박；셴하이 천；장-아 조지 우；샤오자 왕；홍메이 장；롱-창 량
申请人:사이픽스 이미징, 인코포레이티드；
IPC主号:

专利说明:

PROCESS FOR ROLL-TO-ROLL MANUFACTURE OF A DISPLAY BY SYNCHRONIZED PHOTOLITHOGRAPHIC EXPOSURE ON A SUBSTRATE WEB}
[2] Electrophoretic displays are non-luminescent devices based on electrophoretic phenomena that affect charged pigment particles suspended in a solvent. This general type of display was first proposed in 1969. Electrophoretic displays are typically a pair of opposing and spaced apart plate-shaped electrodes, with electrodes having spacers that predetermine a predetermined distance between the electrodes. One of the electrodes is generally transparent. Between the two plates a suspension consisting of colored solvent and charged pigment particles is enclosed.
[3] When a voltage difference is applied between the two electrodes, the pigment particles move to one side by attraction to a plate of polarity opposite to that of the pigment particles. Thus, the color represented in the transparent plate may be determined either by the color of the solvent or the color of the pigment particles by selectively charging the plates. Inverting the plate polarity allows the particles to move back to the opposite plate and invert the color. Neutral density (or shade of gray) due to the intermediate pigment concentration in the transparent plate may be obtained by controlling the plate charge over a range of voltages.
[4] One of the advantages of electrophoretic displays (EPD) over other types of flat panel displays is that the power consumption is very low. These significant advantages make EPDs particularly suitable for portable and battery devices such as laptops, cell phones, personal digital assistants (PDAs), portable electronic medical and diagnostic devices, global positioning system (GPS) devices, and the like.
[5] In order to prevent unwanted movement of particles such as precipitation, a method of separating the space into smaller cells has been proposed by forming partitions between the two electrodes. See, eg, MA Hopper and V. Novotny, IEEE Trans. Electr. Dev., 26 (8): 1148-1152 (1979). However, in the case of the partition type electrophoretic display, some problems arise in the formation of the partition and the process of enclosing the suspension. In addition, the partition type electrophoretic display has a problem that it is difficult to keep the suspensions of different colors separated from each other.
[6] Attempts have been made to enclose the suspension in microcapsules. U. S. Patent No. 5,961, 804 and U. S. Patent No. 5,930, 026 disclose microencapsulated electrophoretic displays. Such displays have microcapsules arranged substantially two-dimensionally, each microcapsule having an electrophoretic composition consisting of a dielectric fluid and a suspension of charged pigment particles that are visually contrasted with the dielectric solvent. Microcapsules may be formed by interfacial polymerization, in-situ polymerization, or other known processes such as physical processes, in-liquid curing, or simple / composite coacervation. The microcapsules thus formed may be injected into a cell containing two spaced electrodes or they may be "printed" or coated onto a transparent conductor film. Microcapsules may also be immobilized in a transparent matrix or binder sandwiched between two electrodes.
[7] These conventional methods, in particular the electrophoretic displays made by the microencapsulation process disclosed in US Pat. Nos. 5,930,026, 5,961,804, and 6,017,584, have several disadvantages. For example, electrophoretic displays made by microencapsulation processes have the problem of being sensitive to environmental changes (particularly to moisture and temperature) due to the wall chemistry of the microcapsules. In addition, electrophoretic displays based on microcapsules have poor scratch resistance due to the thin walls and large particle sizes of the microcapsules. In order to improve the handleability of the display, microcapsules must be embedded in a large amount of polymer matrix, which results in a long response distance between the two electrodes, resulting in a slow response time and a low effective payload of pigment particles. In addition, it is difficult to increase the surface charge density on the pigment particles because charge control agents tend to diffuse into the water / oil interface during the microencapsulation process. The low charge density or zeta potential of the dye particles in the microcapsules also slows the response speed. In addition, because of the large particle size of microcapsules and their wide distribution, this type of electrophoretic display according to the prior art has a problem of poor addressability in resolution and color applications.
[1] The present invention relates to an electrophoretic display, and more particularly to a method and process for producing electrophoretic displays having cells of well-defined shape, size, and aspect ratio, filled with charged pigment particles dispersed in a solvent. It is about. The disclosed processes include roll-to-roll manufacturing of electrophoretic displays by synchronizing photolithographic exposure to the substrate web.
[32] 1 is a schematic cross-sectional view of an electrophoretic display of the present invention, showing three microcups in a neutral state.
[33] FIG. 2 is a schematic cross-sectional view of the electrophoretic display of FIG. 1, in which two of the cells are charged and the pigment moves to one plate. FIG.
[34] 3A-3C are schematic views of an exemplary microcup array manufactured by the method of the present invention, in which FIG. 3A shows a perspective view, FIG. 3B shows a top view, FIG. 3C shows a front view, and the vertical length is exaggerated for clarity. It is.
[35] 4A-4D are a sequence of cross sections of an exemplary microcup array of the present invention, showing the steps of a preferred method of manufacturing a monochrome display in this embodiment of the EPD of the present invention.
[36] 5A and 5B show basic process steps for microcup manufacture including photolithographic image exposure (“top exposure”) through a photomask of a conductor film coated with a thermosetting precursor to UV radiation.
[37] 6A and 6B show different process steps for fabricating a microcup comprising photolithographic image exposure of a base conductor film coated with a thermosetting precursor to UV radiation, where the base conductor pattern on the transparent substrate is a photomask (“bottom”). It acts as a substitute for "exposure" and is impermeable to radiation.
[38] 7A and 7B involve an imagewise photolithographic method that combines the top and bottom exposure principles, whereby the walls are unilaterally by top photomask exposure and by bottom exposure through an opaque base conductor film. ("Mixed exposure") Other process steps for making microcups by curing in the vertical direction.
[39] 8A and 8B of FIG. 8 illustrate the method steps of FIGS. 5A-5C performed by the novel synchronous roll-to-roll photolithographic apparatus of the present invention.
[40] 9A-9H illustrate an example of producing a multicolor electrophoretic display by the method of the present invention.
[41] 10A and 10B of FIG. 10 illustrate the method steps of FIGS. 9A-9H performed in a novel synchronous roll-to-roll photolithographic apparatus of the present invention using a positively acting photoresist stack or coding. Indicates.
[42] 11 schematically illustrates an exemplary semi-continuous process for producing a three color EPD microcup array assembly.
[8] The electrophoretic display (EPD) of the present invention has cells having a well-defined shape, size, and aspect ratio, which are filled with charged pigment particles dispersed in an optically contrasting dielectric solvent.
[9] The present invention also relates to a novel roll-to-roll method and apparatus in which the manufacture of a display can be carried out continuously by a synchronized photolithographic process. Synchronized roll-to-roll methods and apparatuses are also useful for fabricating structures and assemblies of liquid crystal displays (LCDs), and other electronic devices.
[10] One embodiment of the present invention is directed to a support web comprising a patterned conductor film, such as addressable indium-tin oxide (ITO) lines, which are formed integrally with one another as part of a two-dimensionally configured array assembly. It relates to the production of a plurality of microcups to be formed. Each microcup array assembly is filled with a suspension or dispersion of charged pigment particles in a dielectric solvent and sealed to form an electrophoretic cell.
[11] The substrate web on which the microcups are formed preferably comprises a display addressing array having a preformed conductor film, such as ITO conductor lines. Conductor films (ITO lines) and support webs are coated with a layer of radiocurable polymer precursor. Thereafter, the film and precursor layer are image exposed with radiation (defined below) to form the microcup wall structure. Following exposure, the precursor material is removed from the unexposed areas, leaving cured microcup walls that adhere to the conductor film / support web. Image exposure by UV or other radiation forms through the photomask produces an image or predetermined exposure pattern of the radiation-curable material coated on the conductor film. Although no mask is generally required, the transparent mask portions are aligned with the spaces between the ITO lines, since the mask can be placed and aligned with respect to the conductor film, i.e. the ITO lines, and the opaque mask portions are made of ITO material The cup cell floor regions).
[12] Alternatively, the microcup array is manufactured by a process comprising embossing a thermoplastic or thermoset precursor layer coated on a conductor film using a male mold that is pre-patterned and then separating the male mold. May be The precursor layer may be cured by spinning, cooling, solvent evaporation, or other means. This new microembossing method is included in the pending subject specification filed March 4, 2000, entitled "An Improved Electrophoretic Display and Novel Process for Its Manufacture".
[13] By any of the methods described above, it is possible to produce microcups having a wide range of sizes, shapes and aperture ratios, which are solvent resistant and thermodynamically stable.
[14] Still another embodiment of the present invention provides a method of filling a microcups with a single pigment suspension composition, sealing the microcups, and finally sealing the microcup array with a second conductor film pre-coated with an adhesive layer. By laminating to the present invention, the invention relates to the production of monochrome electrophoretic displays from microcup assemblies.
[15] Yet another embodiment of the present invention is directed to manufacturing color electrophoretic displays from microcup assemblies by a sequential selective opening process and a filling process of certain microcup subsets. The process includes laminating or coating the preformed microcups with a positive photoresist layer, image exposing the positive photoresist, and then selectively opening a predetermined number of microcups by developing the resist. Filling the opened cups with a colored electrophoretic fluid, and sealing the filled microcups by a sealing process. These steps may be repeated to create sealed microcups that are filled with electrophoretic fluids of different colors. Thus, the array may be filled with differently colored compositions in a given area to form a color electrophoretic display. Various known pigments and dyes offer a wide range of color options for solvent particles and suspended particles. Known fluid applications and filling mechanisms may be used.
[16] Another embodiment of the present invention can be used in a number of valid processes, including a process for manufacturing a microcup array and a process for selectively filling the microcup array to form a color display assembly. A two-roll photolithographic exposure method and apparatus are disclosed. Roll-to-roll photolithographic image exposure moves in synchronization with a moving web substrate to allow image exposure of the workpiece (eg, microcup array or color display) in a continuous and continuous manner. It is preferable to make it through a mask.
[17] The premasked photomask may be an extended strip that is formed as a continuous loop. The photomask pattern corresponds to the structural shape of a microcup array or other subject device, such as microcup walls and top openings. The photomask may project an image of the microcup array structure by radiation passing through the photomask. "Imagewise" exposure selectively exposes the radiation-sensitive material to form an image structure, leaving the intervening material unexposed. The photomask loops are supported and aligned by alignment mechanisms to make the photomask loops adjacent to the web and form part of the photomask loop in a direction parallel to the part of the web that is generally exposed.
[18] Synchronous movement of the photomask and the web involves moving the photomask loop adjacent the web parallel to the web in substantially the same direction. Indeed, the photomask loop is " rotated " in synchronic motion with respect to the web in close proximity to the exposed web portion. By controlling the relative movement of the web and photomask, the microcup pattern of the mask is aligned with the structures that are "image exposed" on the web during exposure. In a continuous synchronous movement and exposure process, the web and mask are moved in the same direction and at the same speed during exposure to keep the alignment constant.
[19] Alternatively, using semi-continuous synchronous movement, the mask and web are moved by the same incremental distance prior to exposure while being fixed during exposure.
[20] In the roll-to-roll method, the photomask is synchronized with the movement of the support web using a coupling, a mechanism such as a feedback circuit, or a joint drive to maintain equal movement (ie moving at the same speed). Can be.
[21] When manufacturing individually patterned microcup arrays, the roll-to-roll photolithographic exposure apparatus can accept a conductive film / substrate web coated with a radiocurable composition as a continuous strip in a high speed process. Following exposure, when the web moves to the developing region, the unexposed material is removed here to form a microcup wall structure. Since the microcups and ITO lines have a selected size and are preferably equally aligned with the photomask, each completed display cell (ie, filling and sealing the microcups) is individually addressed and controlled by the display processor. . ITO lines may be preformed on either the substrate web by either a wet or dry etching process.
[22] When manufacturing a color display from a microcup array, the synchronous roll-to-roll photolithographic exposure method of the present invention can selectively open, fill, and seal preselected subsets of microcup cells.
[23] Laminating or coating the preformed microcup array, temporarily sealing the microcups with a positive photoresist composition, and sealing the sealed microcup array with image exposure (e.g., using a corresponding photomask). To selectively expose the top openings of the desired subset of microcups. Known lamination and coating mechanisms may also be used. Thereafter, the exposed portion of the photoresist is removed with a developer to open the top of the selected microcup subset. The term "developer" in this context refers to any suitable known means for selectively removing the exposed photoresist while leaving the unexposed photoresist in place.
[24] Thus, an array of cell patterns may be sequentially filled with some different color compositions (typically three primary colors). For example, the image exposure method may use a positively acting photoresist stack, which first seals the empty microcups. Thereafter, the microcups are exposed through a mask (eg, a photomask loop in the disclosed roll-to-roll process) to expose only the first selected subset of microcups. The exposed photoresist is developed and removed with a developer and the first microcup subset is opened and filled with a color pigment dispersion composition selected by one of the methods described above and then sealed. The exposure and development processes are repeated to expose and open the microcup subset of the second choice and to seal after filling with the second pigment dispersion composition. Finally, the remaining photoresist is removed and the third subset of microcups is filled and sealed.
[25] Yet another embodiment of the present invention relates to sealing microcups after filling them with an electrophoretic fluid containing a dispersion of charged pigment particles in the dielectric fluid. Prior to the filling step, it is desirable to disperse and seal the thermoplastic or thermoset precursor in the electrophoretic fluid. Thermoplastic or thermoset precursors do not mix with dielectric solvents and have a lower specific gravity than solvent and pigment particles. After filling the microcups, the thermoplastic or thermoset precursor is image separated from the electrophoretic fluid, forming a floating layer on top of the electrophoretic fluid.
[26] Thereafter, the sealing of the microcups is facilitated by curing the precursor layer by solvent evaporation, interfacial reaction, moisture, heat or radiation. Although two or more curing mechanisms as described above may be used in combination to increase the sealing throughput, UV radiation is the preferred method for sealing microcups. Alternatively, sealing may be achieved by overcoating the electrophoretic fluid with a solution containing a thermoplastic or thermosetting precursor. In order to reduce or eliminate the degree of mixing during the overcoating process, it is very advantageous to use a sealing composition which does not mix with the electrophoretic fluid and preferably has a specific gravity lower than the dielectric fluid. Thereafter, sealing is achieved by curing the precursor by a combination of solvent evaporation, interfacial reaction, moisture, heat, spinning or curing mechanisms. This sealing process is in particular a feature of the present invention.
[27] If the electrophoretic fluid described above is replaced with a suitable liquid crystal composition having a usual refractive index that matches the isotropic cup material, a liquid crystal display may be produced by the method of the present invention. In the "on" state, the liquid crystal in the microcups is aligned in the field direction and becomes transparent. In the "off" state, the liquid crystals are not aligned and disperse the light. In order to maximize the light scattering effect, the diameters of the microcups generally range from 0.5 to 10 μm.
[28] In summary, the roll-to-roll process of the present invention may be used to carry out a series of processes on the web by sequentially transporting one continuous web to a plurality of process locations.
[29] For example, the microcups may be formed, filled, sealed and stacked in a continuous order.
[30] In addition to forming and filling microcup arrays, a synchronous roll-to-roll process may be used to manufacture a wide range of structures, or to manufacture individual patterns of electronic devices that may be formed on a supporting web substrate, such as a flexible circuit board. You can also apply. As in the methods and apparatus for EPD microcups described herein, a pre-patterned photoresist is produced, comprising a plurality of photomask portions corresponding to the components of the subject device. Each such photomask portion may have a transparency that is preselected for radiation or a preselected opacity for radiation, thereby forming an image of these components on a portion of the web that is correspondingly aligned during exposure. The method of the present invention may be used to selectively cure the constituent material during the manufacturing process or to expose photoresist materials that act positively or negatively.
[31] As mentioned above, this multi-step process can be carried out roll-to-roll continuously or semi-continuously, so that the processes are suitable for mass production and low cost production. In addition, these processes are efficient and inexpensive compared to other processes for mass production operations. Electrophoretic displays made by the present invention are not sensitive to environments such as humidity and temperature. Such displays are thin, flexible, durable, easy to handle and flexible in form. The electrophoretic display produced by the present invention has cells having desirable aspect ratios and well defined shapes and sizes, so that bistable reflective displays have excellent color addressability, high contrast ratio, and fast switching speed. In addition, the apparatus and method of the present invention described above relates to an electrophoretic display that is economically suitable for mass production, whereby the low power consumption characteristics of EPD can be utilized in a wider range of consumer, scientific, commercial and industrial electronics.
[43] Hereinafter, the present invention will be described in detail by way of example without limiting the principles of the present invention. These descriptions enable those skilled in the art to make and use the invention, and include several embodiments, adaptations, variations, alternatives, and examples of the invention, including what is presently considered to be the best mode for carrying out the invention. Explain.
[44] In this regard, while the invention has been shown in several drawings, many of the parts, interrelationships, and subcombinations thereof in the present invention have sufficient complexity that cannot be expressly or meaningfully represented by a single patent type of drawing. Accordingly, some of the drawings are schematically shown, or omissions of non-essential parts from the drawings for the description of particular features, aspects or principles of the invention disclosed are omitted. Therefore, one characteristic of the embodiment of the optimum mode may be shown in one figure, and another characteristic of the optimal mode may be shown in another figure.
[45] Some embodiments are provided herein to enable those skilled in the art to more clearly understand and to practice the present invention. These exemplary processes, methods, compositions and apparatus are not intended to limit the scope of the invention but should only be considered as examples and specimens of the invention.
[46] All publications and patent applications cited in this specification are referred to herein as if each individual publication or patent application was expressly and individually referenced.
[47] Justice
[48] Unless defined otherwise herein, technical terms are used according to conventional definitions commonly used and understood by those skilled in the art.
[49] The term "microcup" refers to cup-shaped recesses, which may be created by methods such as microembossing or image exposure. Also, in the overall context, a plurality of forms of “microcups” may generally refer to a microcup assembly having a plurality of microcups that are completely formed or combined to make a two-dimensional microcup array.
[50] In the context of the present invention, the term "cell" means a single unit formed from a sealed microcup. The cells are filled with charged pigment particles dispersed in a solvent or solvent mixture.
[51] The term " well defined " when describing microcups or cells is intended to indicate that the microcups or cells have a precise shape, size, and aspect ratio predetermined according to certain parameters of the manufacturing process.
[52] The term "aspect ratio" is a term known in the art of electrophoretic displays. In this application, the term "aspect ratio" applied to a microcup refers to a depth to width or a depth to width ratio of the microcup opening.
[53] The term " image exposure " refers to the structure of the microcups by exposing the radiation-curable material or photoresist composition to radiation, such as UV, using one of the methods of the present invention to control portions of the material so exposed. Forming a pattern or " image " that corresponds to, for example, exposure to portions of the material corresponding to the microcup walls, except for the unexposed microcup bottom portion. In the case of selectively opening the photoresist of certain portions of the microcup array, image exposure means exposing portions of material corresponding to the cup opening, except for the unexposed microcup walls. The pattern or image may be formed by methods such as exposure through a photomask, or else may be formed by controlling particle beam exposure or the like.
[54] Microcup Array and Method of the Invention
[55] 1 and 2 are schematic cross-sectional views of an exemplary microcup array assembly embodiment, for simplicity, showing three microcup cells 12a, 12b, 12c of the microcup array assembly 10.
[56] As shown in FIG. 1, each cell 12 of the array 10 has two electrode plates 11, 13, at least one of which is a transparent electrode, such as an indium-tin oxide (ITO) electrode. The electrodes 11, 13 abut two opposite faces of the cell 12.
[57] The microcup cell array assembly 10 has a plurality of cells disposed adjacent to each other in a plane to form a layer of cells 12 enclosed between two electrode layers 11, 13. Three exemplary cells 12a, 12b, and 12c, bounded by respective electrode plates 11a, 11b, and 11c (transparent plates) and 13a, 13b, and 13c (back plates), are shown. It can be seen that these multiple cells can be preferably arranged two-dimensionally (right / left and in / out of the plane of FIG. 1) to form a two-dimensional shaped sheet-like display with some selection area. have. Also, for clarity, although FIG. 1 is shown as an example bounded by individual electrode plates 11 and 13 having a width of a single cell, some microcup cells may be bounded by a single electrode plate 11 or 13. It may be.
[58] The cells have a well defined shape and size and are filled with colored dielectric solvent 14 in which the charged pigment particles 15 are suspended and dispersed. The cells 12 may be filled with pigments and solvents of the same composition, respectively (eg monochromatic displays) or may be filled with pigments and solvents of different compositions (eg full color displays). FIG. 1 shows the designated solvents 14a, 14b, and 14c, respectively, and the designated pigment particles 15a, 15b, and 15c, respectively, in each cell 12a, 12b, and 12c in different hatching patterns. As shown, three different color combinations are shown.
[59] Each of the microcup cells 12 has enclosed walls 16 bordering the cells on the side, and on one side, in this example, a floor 17 bordering the cell on the side adjacent to the electrode 13. ). On the opposite surface (adjacent electrode 11), each cell has a cap seal 18. In the case where the cap seal is adjacent to the transparent electrode (as in FIG. 1), the cap seal 18 comprises a transparent composition. In the embodiment of FIG. 1 the floor 17 and the cap seal 18 are shown with separate cell portions different from the adjacent electrodes 13, 111, respectively, but another embodiment of the microcup array 10 of the present invention. The forms may have a complete floor / electrode structure or a complete cap seal / electrode structure.
[60] FIG. 2 is a schematic cross-sectional view of the electrophoretic display of FIG. 1, moving the pigment to one plate by two of the charged cells 12a, 12c. When a voltage difference is applied between the two electrodes 11, 13, the charged particles 15 move to one side (ie toward the electrode 11 or 13 depending on the particles and the charge of the electrode), and the pigment particles Either the color of (15) or the color of solvent (14) can be seen through the transparent conductor film (11). By patterning at least one of the two conductors 11 or 13 (individually addressable parts), either each cell or a group of predefined cells (e.g. forming a pixel) An optional electric field can be set for.
[61] In the example of FIG. 2, two charged cells 12a, 12c are shown in which pigments 15a and 15c have moved to respective transparent electrode plates 11a and 11c. The remaining cells 12b remain neutral (pigment 15b is dispersed throughout solvent 14b).
[62] 3A-3C are schematic views of a portion of an exemplary microcup array manufactured by the method of the present invention, in which FIG. 3A is a perspective view, FIG. 3B is a top view, and FIG. 3C is a front view, and the vertical length is exaggerated for clarity. It is. In reflective electrophoretic displays, the opening area of each individual microcap is from about 10 ² to about 5 x 10 ⁵ It is preferably in the range of about 10 ³ to about 5 × 10 ⁴ It is more preferable to exist in the range of. The width w of the microcup 12 (distance between adjacent walls 16) may vary over a wide range and may be selected to suit the desired final display characteristics. The width w of the microcup openings preferably ranges from about 15 to about 450 μm, more preferably from about 25 to about 300 μm, from edge to edge of the opening. Each microcup may form a small segment of the final display pixel, or may be a full pixel.
[63] The wall thickness t for the microcup width w may vary over a wide range and may be selected to suit the desired final display characteristics. The microcup wall thickness is preferably about 0.01 to about 1 times the microcup width, and more preferably about 0.05 to 0.25 times the microcup width. The ratio of the openings to the wall area is preferably in the range of about 0.05 to about 100, more preferably in the range of about 0.4 to about 20.
[64] To clarify the microcup wall height (h) (which defines the microcup depth), it is exaggerated beyond the normal proportional dimension. Although the wall height may have a wide range with respect to the microcup width w, the optimum height depends greatly on the solvent and pigment properties and the desired operating field. Thus, the wall height may be chosen to optimize the display response characteristics and does not have any constant relationship with the cell width. The height proportional to the wall may be generally larger in smaller microcups than in wide microcups. In particular, the wall height is less than the microcup width. The height of the microcups is preferably in the range of about 3 to about 100 microns (μm), more preferably in the range of about 10 to about 50 μm.
[65] For simplicity and clarity, assume that a square microcup arranged in a linear two dimensional array assembly is disclosed as the microcup array assembly of the present invention. However, the microcups need not be square, and the microcups may be rectangular, circular, or more complex shapes as desired. For example, the microcups can be hexagonal and can be arranged in an array close to the hexagon, or alternatively, the triangular cups can be configured to form hexagonal sub-arrays alternately arranged in an array close to the hexagon. It may be.
[66] In general, the microcups may be of any shape and their size and shape may vary throughout the display. This can be an advantage of color EPDs. In order to maximize the optical effect, microcups of different shapes and sizes may be mixed. For example, a microcup filled with a red dispersion may have a different shape or size than a green microcup or a blue microcup. In addition, the pixel may be configured by varying the number of microcups having different colors. For example, a pixel may consist of a small number of green microcups, a large number of red microcups, and a small number of blue microcups. It is not necessary to have the same shape and number for the three colors.
[67] The openings of the microcups may be round, square, rectangular, hexagonal or any other shape. In order to achieve high saturation and contrast while maintaining desirable mechanical properties, it is desirable that the partition area between the openings is small. Thus, for example, honeycomb-shaped openings are preferable to circular openings.
[68] Preparation of Electrophoretic Displays from Microcup Arrays
[69] A preferred process for making a microcup array is shown schematically in FIGS. 4A-4D.
[70] As shown in FIG. 4A, the microcup array 40 may be manufactured by any other method of the present invention, such as the embodiment shown in FIGS. 5, 6, and 7. The unfilled microcup array manufactured by the methods disclosed herein generally includes a substrate web 43 on which base electrodes 42 are deposited. The microcup wall 41 extends upwardly from the substrate 43 to form an opening cup.
[71] As shown in FIG. 4B, the microcups are filled with a suspension of charged pigment particles 45 in the colored dielectric fluid composition 44. In the example shown, the composition is the same in each cup, ie in a monochrome display. Hereinafter, an example of an assembly of a color display using three different color solvent / pigment compositions will be described in FIG. 9.
[72] As shown in FIG. 4C, after filling the microcups, the microcups are sealed with a seal or cap layer 46 that adheres to the microcup wall and prevents solvent leakage. As an example of a generally preferred sealing method, a thermosetting precursor sealing composition 46a is added to the solvent / pigment composition 44/45. The thermosetting precursor composition 46a does not mix with or dissolve in the solvent and has a specific gravity lower than that of the solvent and the pigment particles. The thermosetting precursor 46a is separated from the solvent 44 in the liquid state to form a floating layer on top of the solvent 44 in the liquid state. Thereafter, the thermosetting precursor 46a is cured (optionally by heat or moisture) by radiation such as UV to form an adhesive sealing cap 46b that seals the microcups 40. Alternatively, the sealing of the microcups may be accomplished by directly overcoating and curing the layer of thermosetting precursor composition to the surface of the electrophoretic fluid. Details of the sealing methods are described in the sections below.
[73] As shown in FIG. 4D, a sealed array of electrophoretic microcup cells 40 is formed with a second conductor film 47, preferably a pressure sensitive adhesive, a hot melt adhesive, or a thermoset, moisture curable or An adhesive layer 48, which may be a radiocurable adhesive, is laminated with a second conductor film 47 that is precoated. The laminated adhesive may be subsequently cured by radiation of UV 68 or the like through the upper conductor film when the upper conductor film transmits radiation.
[74] Preparation of Pigment / Solvent Suspension or Dispersion Composition
[75] As described herein with respect to various embodiments of the EPD of the present invention, the microcups are filled with charged pigment particles dispersed in a dielectric solvent (eg, solvent 44 and pigment particle 45 in FIG. 4B). It is preferable. Dispersions can be found in the art, such as US Pat. Nos. 6,017,584, 5,914,806, 5,573,711, 5,403,518, 5,380,362, 4,680,103, 4,285,801, 4,093,534, 4,071,430, and 3,668,106. It may also be prepared according to known methods. In addition, IEEE Trans. Electron Devices, ED-24, 827 (1977) and J. Appl. Phys. 49 (9): 4820 (1978).
[76] Charged pigment particles are visually contrasted with the medium in which the particles are suspended. For high particle mobility, the medium is a dielectric solvent having a low viscosity and a dielectric constant in the range of about 2 to about 30, preferably in the range of about 2 to about 15. Examples of suitable dielectric solvents include hydrocarbons such as decahydronaphthalene (DECALIN), 5-ethylidene-2-norbornene, fatty oil and paraffin oil; Aromatic hydrocarbons such as toluene, xylene, phenylxylylethane, dodecylbenzene and alkylnaphthalene; Halogenated solvents such as dichlorobenzotrifluoride, 3,4,5-trichlorobenzotrifluoride, chloropentafluoro-benzene, dichlorononane and pentachlorobenzene; Perfluorodecalin, perfluorotoluene, perfluoroxylene, MN Perfluoro solvents such as FC-43, FC-70 and FC-5060 from 3M of Paul; Poly (perfluoropropylene oxide) from TCI Amerca, Portland, Oregon, poly (chlorotrifluoroethylene) such as Halocarbon Oils from Halocarbon Product, River Edge, NJ, Galden, Ht-200 from Ausimont, and Fluorlink or Delaware Low molecular weight halogens containing polymers such as perfluoropolyalkyl ethers such as Krytox Oils from Dupont and Greases K-Fluid Series. In one preferred embodiment, poly (chlorotrifluoroethylene) is used as the dielectric solvent. In another preferred embodiment, poly (perfluoropropylene oxide) is used as the dielectric solvent.
[77] It is also possible to form non-moving fluid pigments from dyes or pigments. In particular, nonionic azo and anthraquinone dyes are useful. Examples of useful dyes include, but are not limited to, Oil Red EGN, Sudan Red, Sudan Blue, Oil Blue, Macrolex Blue, Solvent Blue 35, Pylam Spirit Black, Fast Spirit Black from Pylam Products; Arizona, Sudan Black B of Aldrich; Thermoplastic Black X-70 from BASF; And anthroquinone blue, anthroquinone yellow 114, anthroquinone red 111, 135, anthroquinone green 28 from Aldrich. In particular, in the case of using a perfluorine solvent, fluorinated dyes are usefully used. In the case of pigments, non-movable pigment particles that generate the color of the medium may also be dispersed in the dielectric medium. Such colored particles are preferably not charged. When non-movable pigment particles which generate color in the medium are charged, they are preferably carried a charge which is opposite to the charged mobile pigment particles. If two kinds of pigment particles carry the same charge, they must have different charge densities or different electrophoretic mobility. In either case, the dye or pigment that produces the non-moving fluid pigment of the medium must be chemically stable and able to coexist with other components in the suspension.
[78] Charged, mobile pigment particles include TiO ₂ , phthalocyanine blue, phthalocyanine green, diary lead yellow, diary lead AAOT yellow; Quinacridone, azo, rhodamine, and perylene pigment series from Sun Chemical; Hansa yellow G particles from Kanto Chemical; And organic or inorganic pigments such as Fisher Lamp's Carbon Lampblack. The particle size is preferably submicron. These particles have acceptable optical properties, must not be swollen or softened by a dielectric solvent, and must be chemically stable. In addition, the final suspension must be stable to sedimentation, entanglement, or flocculation under normal operating conditions.
[79] The mobile pigment particles may exhibit an intrinsic charge, may be explicitly charged using a charge control agent, or may be charged by being suspended in a dielectric solvent. Suitable charge control agents are known in the art, which may in fact be polymeric or nonpolymeric, ionic or nonionic, aerosol OT, sodium dodecylbenzenesulfonate, metal soap, polybutene succinimide, Maleic anhydride copolymers, vinylpyridine copolymers, vinylpyrrolidone copolymers (Ganex from International Specialty Products), acrylic (methacrylic) acid copolymers, N, N-dimethylaminoethyl acrylate (methacrylate) copolymers And ionic surfactants. Fluorinated surfactants are particularly useful as charge control agents in perfluorocarbon solvents. Such fluorinated surfactants include FC fluorinated surfactants such as FC-170C, FC-171, FC-176, FC430, FC431, and FC-740 from 3M and Zonyl FSA, FSE, FSN, FSN-100, FSO from Dupont. Zonyl fluorinated surfactants such as, FSO-100, FSD and UR.
[80] Suitable charged pigment dispersions can be prepared by any of the known processes, including grinding, milling, abrasion, microfluidization and ultrasonic techniques. For example, pigment particles in the form of fine powder are added to the suspending solvent and the mixture is ball milled or abraded for several hours to crush the highly aggregated dry pigment powder into primary particles. While less preferred, it is also possible to add dyes or pigments that produce non-moving fluid pigments in suspension during the ball milling process.
[81] The particles may be microencapsulated with suitable polymers to match the specific gravity of the dielectric solvent to its specific gravity, thereby preventing settling or entanglement of the pigment particles. Microencapsulation of the pigment particles can be chemical or physical. Conventional microencapsulation processes include interfacial polymerization, in situ polymerization, image separation, coacervation, electrostatic coating, spray drying, fluid bed coating, solvent evaporation, and the like.
[82] In black / white electrophoretic displays, the suspension consists of charged white particles of titanium oxide (TiO ₂ ) dispersed in a black solvent or charged black particles dispersed in a dielectric solvent. In order to generate the solvent black, black dyes or dye mixtures such as Pylam Spirit Black, Fast Spirit Black of Pylam Products, Arizona, Sudan Black B of Aldrich, and Thermoplastic Black X-70 of BASF, or insoluble black pigments such as carbon black Can be used. For other colored suspensions, there are many possibilities. In a subtractive color system, charged TiO ₂ particles may be suspended in a cyan, yellow or magenta dielectric solvent. Cyan, yellow or magenta can also be generated using dyes or pigments. In additive color systems, charged TiO ₂ particles can be suspended in red, green or blue dielectric solvents generated using dyes or pigments. Red, green and blue systems are preferred for most applications.
[83] Example 1 Pigment Dispersions. To 17.77 g of hot xylene (Aldrich), polystyrene (0.89 g, Polysciences, Inc. molecular weight 50,000) and AOT (0.094 g, American Cyanamide, sodium dioctylsulfosuccinate) were added. Ti-Pure R-706 (6.25 g) was added to the solution, and the mixture was pulverized at 200 rpm for at least 12 hours in a wear mill. A stable dispersion of low viscosity was obtained. Oil-blue N (0.25 g, Aldrich) was added to color the dispersion. The suspension was then tested in a standard electrophoretic cell containing two ITO conductor plates separated by a 24 μm spacer. Alternating white and blue images of high contrast were observed, with a switching time of about 60 Hz, 80 V and a rising time of 8.5 msec.
[84] Example 2 Pigment Dispersions. In addition to using Oil RED EGN (Aldrich), the test of the pigment dispersion of Example 1 was repeated. Alternating red and white images of high contrast were observed, with a switching rate of about 60 Hz and a rising time of 60 m at 12 msec.
[85] Example 3 Pigment Dispersions. In a solution containing 11.2 g of maleic anhydride copolymer (Baker Hughes X-5231), 24 g of 3,4-dichlorobenzotrifluoride (Aldrich), and 24 g of 1,6-dichlorohexane (Aldrich) In the above, Ti-Pure R-706 (112 g) was ground using a wear mill. Similarly, 1.2 g alkylate polyvinylpyrrolidone (100 g of Ganex V216), 34 g 3,4-dichlorobenzotrifluoride, and 34 g 1,6-dichlorohexane (Aldrich) at 100 ° C. In a solution containing 12 g of carbon black was ground. Thereafter, these two dispersions were mixed and tested uniformly. High contrast black and white images were observed, and the rise time was 36 msec at a switching rate of about 10 Hz and 100 V.
[86] Example 4 Pigment Dispersions. A homogenizer is used in a solution containing 1.94 g of Fluorolink D from Ausimont, 0.22 g of Fluorolink 7004 from Ausimont, 0.37 g of fluorinated cyan dye from 3M, and 52.54 g of perfluoro solvent HT-200 (Ausimont). 0.6 g of Ti Pure R706 was dispersed.
[87] Example 5 Pigment Dispersions. Same as Example 4 except that Ti Pure R706 and Fluorolink were replaced with polymer coated TiO ₂ particles of Elimentis (hihstown, NJ) and Krytox (Du Pont), respectively.
[88] Sealing of Microcup Array
[89] As shown in FIG. 4C, the array of filled microcups is enclosed and sealed. Sealing of the microcups can be accomplished by a number of methods. As mentioned above, a preferred method is to disperse a UV curable composition containing polyfunctional acrylate, acrylated oligomer and photoinitiator in an electrophoretic fluid containing charged pigment particles dispersed in a colored dielectric solvent. UV curable compositions do not mix with dielectric solvents and their specific gravity is lower than dielectric solvents and pigment particles. After the two components, the UV curable composition and the electrophoretic fluid have been thoroughly mixed in an in-line mixer, a precise coating mechanism such as Myrad bar method, gravure printing method, doctor blade method, slot coating or slit coating Coating onto the microcups immediately. Excess fluid is removed with a wiper blade or similar device. The electrophoretic fluid remaining on the top surface of the partition walls of the microcups may be cleaned using a small amount of a weak solvent or a mixture of solvents such as isopropanol, methanol, or an aqueous solution thereof. Volatile organic solvents may be used to control the viscosity and coverage of the electrophoretic fluid. Drying the microcups thus filled causes the UV curable composition to float on top of the electrophoretic fluid. After the UV curable composition is suspended at the top or while suspended at the top, the floating UV curable layer is cured to seal the microcups. For curing and sealing the microcups, other types of radiation, such as UV or visible light, IR and electron beams, can be used. Alternatively, when using a heat or moisture curable composition, heat or moisture may be used to cure and seal the microcups.
[90] Preferred groups of dielectric solvents that exhibit good density and solubility identification for acrylate monomers and oligomers are halogenated hydrocarbons and derivatives thereof. Surfactants may also be used to improve adhesion and wetting at the interface between the electrophoretic fluid and the sealing material. Useful surfactants include FC surfactants from 3M, Zonyl fluorinated surfactants from DuPont, fluoroacrylates, fluoromethacrylates, fluoro-substituted long chain alcohols, perfluoro-substituted long chain carboxylic acids and derivatives thereof do.
[91] Alternatively, if the sealing precursor can at least partially coexist with the dielectric solvent, the electrophoretic fluid and the sealing precursor may be sequentially coated into the microcups. In this case, sealing of the microcups can be achieved by overcoating a thin layer of the thermosetting precursor, which can be cured by radiation, heat, moisture or interfacial reactions on the surface of the filled microcups, followed by curing. Interfacial polymerization and subsequent UV curing are very advantageous for the sealing process. By forming a thin barrier layer at the interface by interfacial polymerization, mutual mixing between the electrophoretic layer and the overcoat is remarkably suppressed. The sealing is then completed by a step after curing, preferably by UV radiation. In order to further reduce the mixing between the electrophoretic layer and the overcoat, it is highly desirable that the specific gravity of the overcoat be significantly lower than the electrophoretic fluid. A volatile organic solvent may be used to control the viscosity and thickness of the coating layer. When using a volatile solvent in the overcoat, the volatile solvent is preferably not mixed with the dielectric solvent. Two-step overcoating processes are particularly useful when the pigment used is at least partially soluble in the thermosetting precursor.
[92] Example 6 Microcup Sealing. As an example of the "one-step" process of the present invention, about 0.05 ml of UV containing 1 wt% benzyl dimethyl ketal (Sartomer's Esacure KB1) in HDDA (Aldrich's 1,6-hexanediol diacrylate) The curable composition is 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-non-adeca in 3M FC-43. It was dispersed in 0.4 ml of a dielectric solvent containing 0.5 wt% of nonadecafluoro-1-decanol (Aldrich). This dispersion was immediately filled into a microcup array. Excess fluid was removed with a wiper blade. The HDDA solution was image separated for at least 30 seconds and then cured with UV radiation (10 mw / cm ² ) for about 1 minute. A hard, clean layer was observed at the top of the microcups and the microcups were sealed.
[93] Example 7 Microcup Sealing. In this example, the two-step (overcoding and UV curing) process of the present invention was tested. The electrophoretic dispersion fluid as prepared in the pigment dispersion of Example 3 was encoded on a microcup array. A thin layer of Norland optical adhesive NOA 60 (Norland Products Inc., New Brunswick, NJ) was coated onto the filled microcups. The excess of UV adhesive was removed upon stripping of the Mylar membrane and washed with one sheet of absorbent paper. Thereafter, the overcoated adhesive was cured immediately under a Loctite Zeta 7410 UV exposure apparatus for about 15 minutes. The microcups were completely sealed and no air pockets were observed. The thickness of the cured adhesive layer was about 5-10 μm as measured by Mitutoyo thickness gauge.
[94] Example 8 Microcup Sealing. In this example, the two-step (overcoating and moisture curing) process of the present invention was tested. The microcup sealing test of Example 2 was repeated except that the Norland adhesive was replaced with Instant Krazy glue from Elmer's Products, Columbus, Ohio. Thereafter, the overcoated adhesive was cured for 5 minutes by moisture in the air. The microcups were completely sealed and no air pockets were observed. The thickness of the cured adhesive layer was about 5-10 탆 as measured by a Mitutoyo thickness gauge.
[95] Example 9 Microcup Sealing. In this example, the two-step (overcoating and interfacial polymerization) process of the present invention was carried out. Replace the electrophoretic fluid with a solution of 3,4-dichlorobenzotrifluoride containing 0.3 wt% of tetraethylenepentaamine (Aldrich) and replace Instant Krazy glue with an aliphatic polyisocyanate (Desmodur N 3300 from Bayer) solution in anhydrous ether. The microcup sealing experiment of Example 3 was repeated except that it was replaced with. Strongly crosslinked thin films were observed immediately after overcoating. After ether evaporated at room temperature, the dielectric solvent was completely sealed inside the microcup. No air pocket was observed at all.
[96] Example 10 Microcup Sealing. Samples prepared by the pigment dispersions of Examples 4 and 5 in perfluoro solvent HT200 were diluted using 3M volatile perfluor cosolvent FC-33 and coated onto microcup array. The volatile cosolvent was evaporated to expose the partially filled microcup array. Thereafter, a 7.5% solution of polyisoprene of heptane was overcoated on the partially filled cups using a Universal Blade Applicator with a 6 mm opening. Thereafter, the overcoated microcups were dried at room temperature. Microscopically observed a flawless sealing layer of about 7 μm thick. Slightly entrapped air bubbles were observed in the sealed microcups. Thereafter, the samples were post-treated by UV radiation or thermal baking to further improve barrier properties.
[97] Example 11 Preparation of Radiocurable Materials. The compositions shown in Table 1 were coated onto Mylar J101 / 200 gauges using a nickel chromium bird type film application with an opening of 3 mils. The solvent was evaporated to leave a sticky film having a glass transition temperature (Tg) below room temperature. Thereafter, the coated web was exposed through a mask and UV cured by UV, such as a metal fluoride lamp.
[98] Table 1: PMMA-Containing UV Curable Compositions
[99] numberExplanationingredientSourceWt% OneEpoxy acrylateEbecryl 3605UCB Chemicals7.35 2MonomerStartomer SR205Startomer9.59 3Urethane acrylateEbecryl 6700UCB Chemicals4.87 4Polymethyl methacrylateElvacite 2051ICI9.11 5PhotoinitiatorDarocur 1173Ciba1.45 6Cationic PhotoinitiatorCyracure UVI 6976Union carbide0.60 7menstruumAcetoneAldrich67.03 Sum 100.00
[100] The solvent for image exposure after removing the uncured composition in the process of the invention may be conventional. The solvent may be a conventional solvent or solvent mixture, selected to minimize the degree of swelling of the image cured composition. Common solvents include MEK, MPK, EtOAc, BuOH, isopropanol, methanol, cyclohexanone, dichloroethane, trichloroethane, methoxyethyl alcohol and the like.
[101] Example 12 Preparation of Radiocurable Cup Materials. 12 wt% Ebercryl 600 (UCB CHemicals, smyran, GA), 2.7 wt% Ebecryl 4827, 1 wt% Ebecryl 1360, 6 wt% HDDA (UCB Chmicals), 1 wt% Irgacure 500 (Ciba Specialyt chemicals, Tarrytown, NY) was homogeneously mixed with 5 wt% of MEK (methyl ethyl ketone). The mixed solution was coated on a ITO / PET membrane by a Myrad bar with a target dry thickness of 50 μm. The coded sample was then exposed through a mask and developed using isopropanol.
[102] Example 13 Preparation of Radiocurable Cup Materials. The composition was prepared with 12 wt% Ebecryl 830, 5.5 wt% SR399 (Sartomer, Exton, PA), 2 wt% HDDA, 0.488 wt% Ebecryl 1360, 0.1 wt% Irgacure 369 (Ciba SPecialty Chemicals), 0.02 wt% The process of Example 12 was repeated except that it was replaced with isopropyl thioxanthone (Aldrichy) and 10 wt% of MEK.
[103] Example 14 Preparation of Radiocurable Cup Materials. The composition was prepared with 7 wt% Ebecryl 600, 8 wt% SR399, 1 wt% HDDA, 2.6 wt% Ebecryl 4827, 1.4 wt% Ebecryl 1360, 0.1 wt% Irgacure 369, 0.02 wt% ITX, and 10 The process of Example 13 was repeated except that it was replaced by wt% MEK.
[104] Photolithography Method of Manufacturing Microcup Assemblies
[105] A typical lithographic process for manufacturing the microcup assembly (40 in FIG. 4) of the present invention is shown in FIGS. 5, 6, 7, and the specific synchronized roll-to-roll lithographic apparatus and method of the present invention Explain.
[106] Embodiment of a top exposure method. As shown in Figs. 5A and 5B, the radiation-curable material 51a coated by the known methods on the conductor electrode film 52 is passed through a mask 56 such as UV light (and optionally radiation, electron beam, or the like). And the walls 51b corresponding to the image projected through the mask 56 to form the microcup array 50. It is preferable to provide the base conductor film 52 on the support substrate base web 53 which may be provided with a plastic material.
[107] In the photomask 56 of FIG. 5A, the black square 54 represents an opaque region, and the space between the black squares represents the opening (transparent) region 55 of the mask 56. UV emits through the opening area 55 on the radiocurable material 51a. Since UV does not pass through the substrate 53 or the base conductor 52 (upper exposure), it is preferable to directly expose the radiation-curable material 51a. For this reason, neither the substrate 53 nor the conductor 52 should project UV or other radiation wavelengths used.
[108] As shown in Fig. 5B, the exposed regions 51b are hardened, and the unexposed regions 51c (protected by the opaque regions 54 of the mask 56) are removed by a suitable solvent or developer to remove microorganisms. Form cups 57. The solvent or developer is selected from those commonly used to weaken or reduce the viscosity of radiocurable materials such as methylethylketone, toluene, acetone, isopropanol and the like. In the case where UV light is emitted from the bottom through the photomask, the preparation of the microcups may be similarly made by placing the photomask under the conductor film / substrate base web.
[109] Floor exposure and combination method. Two different methods of making the microcup array of the present invention by image exposure are shown in FIGS. 6A and 6B and 7A and 7B. These methods use a conductor pattern as a mask and use a UV exposure method through a substrate web.
[110] In FIG. 6A, the conductor film 62 used has a cell base electrode portion 64 that is previously patterned and corresponds to the floor portions of the microcups 67. The base portions 64 are opaque to the UV wavelength (or other radiation) used. The space 65 between the conductor base portions 62 is substantially transparent or projected onto the UV light. In this case, the conductor pattern functions as a photomask. As disclosed in FIG. 6A, a radiation-curable material 61a is coated on the substrate 63 and the conductor film 62. When the material 61a is exposed by UV light projected "upwards" through the substrate 63, the region not shielded by the conductor 62, that is, the region corresponding to the space 65 is cured. As shown in FIG. 6B, as described above, the uncured material 61c is removed from the unexposed regions and the cured material 61b is left to form walls of the microcups 67.
[111] 7A illustrates a combination method of producing the microcup array 70 of the present invention using the top exposure and bottom exposure principles. The base conductor film 72 is also opaque and line patterned. The radiation curable material 71a coated on the base conductor 72 and the substrate 73 is exposed from below through the conductor line pattern 72 serving as the first photomask. The second exposure is performed through the second photomask 76 having a line pattern orthogonal to the conductor lines 72 from the "upper" side. The spaces 75 between the lines 74 are substantially transparent or transparent to UV light. In this process, the wall material 71b in one direction is cured from bottom to top, and the wall material in the orthogonal direction is cured from top to bottom, and they combine to form a complete microcup 77.
[112] As shown in Fig. 7B, the unexposed areas are removed with the solvent or developer described above to form the microcups 77.
[113] Synchronous Roll-to-Roll Photolithographic Process for Manufacturing Microcups
[114] Photolithographic processes (such as those disclosed in FIGS. 5A and 5B) for making microcup arrays disclosed herein may also be used in the novel synchronous roll-to-roll photolithography process. In a roll-to-roll process, the photomask can be synchronized with the substrate web and moved at the same speed as the substrate web to continuously produce the microcup array of the present invention in the form of a continuous strip assembly.
[115] As a preferred example of the roll-to-roll process disclosed herein, the electrodes are placed in an "orthogonal electrode (ITO) line" aligned with the microcups (ie, the walls of the microcups are spaced between the base ITO lines and Align). Separating the space by the walls formed between the electrodes can facilitate pixelation and x-y addressing of individual pixels (microcups). For the x-y addressing and pixels of the individual cups, the electrode lines are orthogonal (ie, the upper electrode lines are orthogonal to the base electrode lines). Thus, when the microcup cell assembly process is complete (see, eg, FIG. 4), it is desirable to place the microcups at the intersection of orthogonal top and base ITO lines. As a result, the base electrode or ITO lines are placed or inserted into the substrate web as a series of parallel conductor lines patterned prior to microcup configuration. The ITO lines preferably have the same width as the microcups.
[116] Addressable EPDs are known and various techniques have been proposed to address addressability issues, such as threshold voltage issues, including control electrode techniques. See, eg, B. Singer and AL Dalisa, Proc. SID, Vol. 18/3 & 4, 3 ^rd and 4 ^th Quarters, pp 255-266 (1977). However, synchronous roll-to-roll lithographic processes are inherently flexible and may be used to fabricate EPD microcup arrays in a wide range of electronic configurations and electronic designs. Alternatively, various types of electronic components and / or conductors may be inserted into the substrate web, for example, prior to feeding the web of the roll-to-roll process disclosed herein to form microcups on the web. It may be placed on either side of the web. As such, these components are provided or installed at the bottom of the web to form microcups. Similarly, the microcup forming processes disclosed herein may be used to fabricate cup-shaped bulkheads of displays and other devices in addition to EPDs.
[117] 8 shows an exemplary embodiment of the preferred roll-to-roll photolithographic manufacturing apparatus 80 of the present invention for producing a microcup array 81 of the electrophoretic display of the present invention, wherein the apparatus 80 ) And the intersection of the strip microcup array 81 which is developed continuously. The microcup array may be made by image exposure through a photomask 82 of a radiation-curable material 84a coated to cover the substrate web 86 and the conductor film ITO lines 88. Known coating mechanisms may be used to provide the material 84a to the web 86.
[118] The curable material 84a is preferably a UV curable material and is cured by the UV radiation shown in FIG. 8 to form a stable and rigid polymer 84b, where UV passes through the mask 82 to form the precursor material 84a. Is absorbed by
[119] The direction of the apparatus 80 of FIG. 8 is merely exemplary, and the components may be rearranged in many suitable orientations to perform the method steps shown for the vertical direction. Conventional additional supports such as guides, rollers, and the like may be used to support, stretch, redirect, and / or wind the web 86 during the depicted process.
[120] The synchronous roll-to-roll process of the present invention, embodied in the apparatus 80, allows both to be continuously movable and arranged adjacent to each other so that UV radiation through the mask 82 and subsequent curing material 84a Installing photomask 82 and substrate web 86 in a continuous and continuous manner.
[121] In the preferred installation device shown in Fig. 8, the mask 82 is formed in a continuous loop, and is provided to be at least tight with a pair of spaced drive / support cylinders 90 and 91, the mask loop 82 being It has a substantially straight portion 92 which spans between the curved portions 93 fitted around the drive cylinders 90, 91.
[122] When the microcup array 81 is configured, the continuous strip substrate web 86 similarly passes through with at least two spaced apart drive cylinders 100, 101 so that the straight portion of the web 86 ( 103 is aligned parallel to the straight portion of the mask loop 82. The mask drive cylinders 90, 91 are driven to rotate in the direction indicated by the arrow A, and the web drive cylinders 100, 101 are driven to rotate in the direction indicated by the arrow B, so that the mask straight line portion 92 and the web straight line portion The 103 is moved in parallel in the same direction at the same speed. Each of the mask and the web straight portions 92, 103 are preferably spaced apart by a selected small distance, respectively, so that the mask 82 can be prevented from being contaminated from the undeveloped material 84a.
[123] In FIG. 8, a continuous web 86 is fed from the right side inward (toward the UV exposure) and fed to the web storage / extension device 104 (not shown). Similarly, when the developed web (with the formed microphone cup) moves outward (away from the UV exposure), the developed web is treated by the web storage / extension device 105. The devices 104 and 105 may have a known web processing and drive mechanism.
[124] As shown in FIG. 8, the on-site coating of the radiation-curable material 84a is selectively on the substrate web 86 and the conductor film ITO line 88, and the pre-coded web / ITO stock ( stock), for example, in the form of rolls and stored separately. The stored precoated web / ITO stock is dried and then formed without a tack to improve storage capacity. In this method, a higher process temperature may be used in the UV exposure step than the process temperature generally used for on-site coated webs (which can become sticky uncured). Thereafter, the precoated stock is unfolded at point 104 and fed to drive cylinder 100.
[125] After UV exposure, the UV curable material 84a is cleaned or developed with a suitable solvent that removes the uncured (unexposed) material 84a and leaves the cured material 84b in place. Form the cup wall. The term " solvent " in this context refers to suitable known means for removing unexposed precursors and selectively developing the material, leaving the exposed and cured photoresist in place. Known solvent application mechanisms may be used.
[126] After the cleaning step, the developed material 84b is dried and thus the finished microcup array 81 is processed for storage or further processing 105.
[127] 8A shows a plan view of a portion of the mask 82. Lines 8-8 in FIG. 8A primarily define a cross section of the mask 82 shown in FIG. The mask 82 includes an opaque region 110 (generally rectangular in this embodiment) bounded by the transparent mask region 112.
[128] 8B shows a plan view of a developed microcup array 81 portion. Lines 8'-8 'of FIG. 8B primarily define a cross section of the microcup array 81 shown in FIG. The exposed ITO conductor 88 in the microcup floor corresponds to the opaque mask portion 110 and the microcup wall 84b corresponds to the transparent mask portion 112.
[129] UV light shown in FIG. 8 illuminating the mask straight portion 92 may be supplied from a conventional source (not shown). Optionally, the mask drive cylinders 90, 91 may comprise a UV transmissive material, and a UV light source (not shown) may provide additional illumination at the edge of the mask straight portion 92. 91 may be disposed in either or both cylinders. Optionally, additional support rollers or guides (not shown) may be included to further support and align the mask straight portion 92 and / or the web straight portion 103.
[130] 8 shows a process for dispersing the uncured precursor material 84a onto the web 86 after a successive coating step. Known coding mechanisms may be used. Alternatively, the material 84a may be provided to the pre-coded web substrate supplied from the storage / extension device 104 by separate operations.
[131] The photomask 82 may be moved at the same speed using conventional drive control mechanisms to synchronize the movement of the web 86. For example, the drive cylinders 90, 91 are mechanically connected to the drive cylinders 100, 101 (eg, fitted to a common drive motor) to rotate each at the same tangential speed. Alternatively, the drive cylinders are controlled by a conventional feedback circuit to detect the passage of the ITO lines 88 and the passage of the corresponding opaque portion 110 of the mask 82, for example an optical detector. By each of (114, 115), an equal movement can be maintained. Detector signals may be used by a feedback control circuit that adjusts the drive speed to maintain a positive alignment of the corresponding portion in the UV exposure portion 92/103. Other conventional sensor systems such as magnetic sensors, bar code scanners / markers, etc. may be used to provide feedback synchronization control.
[132] As described herein, the thickness of the display produced by these processes of the present invention may be as thin or flexible as a sheet of paper.
[133] The width of the display is preferably the width of the web (generally 3 to 90 inches). Alternatively, the microcup array may be cut to produce smaller displays, or one or more such microcup arrays may be installed adjacent to each other to produce a wider display.
[134] Since the roll-to-roll process can produce microcup arrays of any desired length, the length of the display can be approximately several inches to thousands of feet depending on the length of the web feed roll.
[135] Other roll-to-roll methods . As shown in FIG. 8, in addition to using the method embodiment (upper exposure) of FIG. 5, the roll-to-roll apparatus of the present invention may optionally use the method of either FIG. 6 or 7. For example, when using the method of FIG. 7, the web (86 in FIG. 8) comprises a radiation transmitting material. Conductor line (88 in FIG. 8) corresponds to conductor 72 in FIG. 7, which is opaque to radiation, and the web is irradiated from the back portion 103 by an additional UV source (not shown).
[136] Manufacturing and Sealing of Multicolor Electrophoretic Displays
[137] An important aspect of the present invention is a method of producing colored electrophoretic displays by selectively filling microcups in a predetermined multicolored pattern using pigment suspensions of different colors. The manufacturing steps of the multicolor electrophoretic display,
[138] (1) laminating or coating the formed microcup array with a positively acting photoresist. Conventional photoresist compositions and developers, such as Shipley (MA), Hunt Chemical (CT), or novolak photoresists from Sumitomo (Japan), may also be used. Removable supports such as, for example, PET-4851 from Saint-Gobain, Worcester, MA; Novolac positive photoresists such as Shipley Microposit S1818; And alkali-developable adhesive layers such as a mixture of Nacor 72-8685 from National Starch and Carboset 515 from BF Goodrich.
[139] (2) image-exposing the photoresist to selectively open a partial set (first subset) of microphone cups, remove the removable support film, and develop the positive photoresist with a developer such as Shipley's diluted Microposit 351 developer; step;
[140] (3) filling the opened cups with an electrophoretic fluid containing charged white pigment (TiO ₂ ) particles and a dye or pigment of a first primary color;
[141] (4) sealing the filled microcups, as described in the manufacture of monochrome displays; And
[142] (5) repeating steps (2) to (4) of the additional subset of microcups to produce microcups filled with electrophoretic fluids of the second and third primary colors.
[143] 9A-9H illustrate a particular embodiment of making a multicolor electrophoretic display by the method of the present invention, the method comprising the following steps.
[144] 9A: Provides a microcup array having a plurality of separation walls 120 installed in a web 121, produced by one of the methods described above, to form a microcup cell array 122.
[145] 9B: The microcup array 122 is laminated with a positive dry-film photoresist comprising at least an adhesive layer 123 and a positive photoresist 74. Using a first photomask (not shown), the positive photoresist 124 is exposed to UV, visible or other radiation while limiting image exposure of the first predetermined subset 122a of the microcup array with its mask. Image exposure. Known photoresist compositions and lamination mechanisms may also be used.
[146] 9C: The photoresist 124 is developed to remove the photoresist 124 and the adhesive layer 123 from the selectively exposed microcup subset 122a to form an opening. Known photoresist developing solvents and solvent application mechanisms may also be used.
[147] FIG. 9D: In the opened microcup subset 122a, a thermosetting precursor 126a that does not mix with the solvent and has a lower specific gravity than solvent and pigment particles and a charged pigment dispersion 125a in a dielectric solvent corresponding to the first primary color ). After or during the separation of the thermosetting precursor to form a floating layer on top of the liquid phase, the thermosetting precursor 126a is cured (preferably by radiation such as UV, less preferably by heat or moisture), One subset of microcups 122a is sealed to form a sealed electrophoretic cell containing the electrophoretic fluid of the first primary color. Sealing of the microcups may optionally be accomplished by directly coating the layer of thermosetting precursor material on the surface of the liquid phase 125a.
[148] FIG. 9E: Repeat the steps shown in FIG. 9B for the second selected microcup subset 122b of the microcup array to expose the second selected microcup subset 122b by the second mark. Optionally, the first mask may be moved and rearranged to expose the second subset.
[149] 9F: Repeat the steps shown in FIG. 9C for the second selection subset 122b of the microcup array to open the second microcup subset 122b.
[150] 9G: Repeat the steps shown in FIG. 9D for the second selection subset 112b of microcups to fill the second microcup subset with the pigment / solvent dispersion 125b corresponding to the second primary color, The second subset 122b is sealed with a sealant to form a sealed electrophoretic cell.
[151] FIG. 9H: Repeat the steps shown in FIGS. 9B-9D for the third selection subset 122c of microcups to expose, open, fill, and seal the second subset 122c, and a third primary color. To form an enclosed electrophoretic cell. Thereafter, the remaining photoresist 124 and adhesive layer 123 are removed. Thereafter, the sealed electrophoretic cell array is a pre-patterned transparent upper conductor film 127, precoated with an adhesive layer 128, which may be a pressure sensitive adhesive, a hot melt adhesive or a thermal, moisture or radiocurable adhesive. Laminated. Curing adhesive to adhere to the cell. Known lamination mechanisms and adhesives may also be used.
[152] Synchronous roll-to-roll process for multicolor electrophoretic displays
[153] An important aspect of the present invention is a roll-to-roll method for producing multicolor electrophoretic displays, wherein the process of FIGS. 9A-9H may be performed in a continuous manner. The method includes exposing the stacked or coated microcup array through the synchronized photomask in synchronization with the microcups and moving at the same speed as the web carrying the stacked microcups. After exposing the selected cups, a positive photoresist is developed to open the exposed area. Thereafter, on the web of any desired length, the color display can be produced by a semi-continuous process that can be subdivided as desired for the final display product.
[154] 10A and 10B illustrate the method steps of FIGS. 9A-9H performed by the novel synchronous roll-to-roll photolithographic apparatus 130 of the present invention using a positively acting photoresist stack. Indicates. Preformed microcup array /, supplied inwards from the upper right, from the array storage / extension device 105 'which may optionally be the output 105 of the roll-to-roll array forming process shown in FIG. The support web 81 is shown.
[155] First, the microcup array 81 is laminated or coated with a continuous strip of positively acting photoresist composition 131 fed inwardly from the photoresist storage device 132. In the case of lamination, the photoresist composition 131 may include the adhesive layer 123 and positive photoresist 124 shown in FIG. 9. Lamination may be accomplished by conventional lamination apparatuses, for example by the pressure of the lamination cylinders 133a and 133b.
[156] The roll-to-roll photolithographic apparatus 130 for producing a color display is substantially similar to the roll-to-roll lithographic apparatus 80 for producing the microcup arrays shown in FIG. 8. In the preferred mounting arrangement shown in FIG. 10, the mask 136 is formed as a continuous loop and is provided to be taut with at least a pair of spaced apart drive / support cylinders 140 and 141, the mask loop 136 Has a substantially straight portion 142 spanning between the bends 143 fitted around the drive cylinders 140 and 141.
[157] Similarly, the microcup array 81 interlocks with at least two spaced apart drive cylinders 150, 151 so that the straight portion 153 of the array 81 is a straight portion of the mask loop 136 ( 142 in parallel. By driving the mask drive cylinders 140 and 141 to rotate in the direction indicated by arrow A, and driving the web drive cylinders 150 and 151 to rotate in the direction indicated by arrow B, the mask straight portion 142 and the web straight line The portions 153 can be moved in parallel at the same speed and in the same direction. Each mask and web straight portion 142, 153 is preferably arranged spaced apart by a selected small distance, respectively. By the methods described above with respect to the roll-to-roll method of FIG. 8, it is possible to synchronize the movement of the photomask 136 with the movement of the microcup array 81.
[158] The orientation of the apparatus 130 of FIG. 10 is merely exemplary, and the components may be rearranged into many suitable orientations to perform the method steps shown for the vertical direction. Additional conventional supports such as guides, rollers, and the like may be used to support, stretch, rotate, and / or wind the microcup array 81 during the depicted process.
[159] 10A is a top view of a portion of mask 136. Lines 10-10 in FIG. 10A primarily define a cross section of the mask 136 shown in FIG. The pattern of synchronized mask 136 has transparent portions 160 dimensioned and aligned to expose the surface of the first subset of microcups, in this embodiment every third microcup in a linear sequence. The opaque portion 162 of the mask prevents the remaining microcups and wall area from being exposed. Following UV or other radiation exposure, when the exposed material 131b is removed with a suitable photoresist developer, the photoresist 131 using an appropriate photoresist developer that leaves the unexposed material 131a in place. ) Is cleaned or processed to create an opening in the stack of exposed microcups. Following the cleaning step, the microcup array may be dried and the microcup array may be processed for storage or further processing 106.
[160] 10B is a plan view showing a part of the microcup array 81 after developing the photoresist 131. Lines 10'-10 'in FIG. 10B primarily define a cross section of the microcup array 81 shown in FIG. Since the exposed conductor 88 of the subset of microcups can be seen through the openings 166 formed by removing the exposed photoresist 131b, the exposed ITO conductor 88 in the microcup floor is a transparent mask. Corresponds to portion 160. The remainder of the microcups and walls are left to be covered by the unexposed photoresist 131a, which corresponds to the opaque mask portion 162. In the embodiment of FIG. 10, the first microcup subset in the transparent mask portion 160 and the developed photoresist openings 166 includes a switch in which every third microphone cup in each row is opened. Has a tagged-offset row.
[161] In FIG. 10, when the microcup array 81 having the first subset openings 166 moves outwards (away from the UV exposure portion), the microcups processed by the second array storage / extension device 106. The array 81 is shown. Optionally, apparatus 106 may further include a processing apparatus for continuous processing. As described above with respect to FIG. 9D, following filling and sealing the opened microcups, using the transparent portion 160 of the mask 136 aligned to expose the second micro subset to create the openings. 10 may be repeated (for the same or additional device 130).
[162] FIG. 11 schematically illustrates a semi-continuous method of manufacturing a three color EPD microcup array assembly using the methods described herein, in particular the methods described above in FIGS. 8, 9, 10. The example process of FIG. 11 begins by feeding inward a conductor / support web that is previously patterned from the web storage device 202. The web forms a continuous strip substrate on which the processes of steps 204 to 238 of FIG. 11 can be performed sequentially. When it is necessary to bring the web sequentially into the positions of the apparatus performing these steps, the web can be moved, redirected and guided by rollers, guide slots or the like (not shown).
[163] In step 204, the web / conductor is coded with a radiocurable precursor material (RCPM). In step 206, the coded web is exposed by the roll-to-roll synchronized photolithographic apparatus of the present invention through a microcup mask. In step 208, the cured microcup array formed on the web is left behind by treating or “cleaning” the uncured RCPM with an appropriate solvent composition.
[164] A photoresist stack or coating that acts positive in step 210 is supplied from the storage device, stacked or coded on the top surface of the microcup array in step 211, and individually sealed microcups to selectively deposit the microcups. Can be charged. Thereafter, in step 212, the microcup array with photoresist is exposed in another roll-to-roll synchronous photolithographic apparatus using a mask configured to expose only the first subset of microcups. In step 214, the microcup array is treated or "washed" with an appropriate solvent composition to remove the exposed portion of the photoresist. In step 212 only the first subset of microcups is exposed, so that only the photoresist of the tops of the first subset of microcups is removed, so that the tops of the first subset are selectively opened. In step 216, the first subset of opened microcups is filled with a first pigment / solvent composition. In step 218, the first subset of opened microcups is sealed and cured as described in FIG. 9 above. The sealing process of step 218 does not include unexposed photoresist.
[165] Thereafter, in step 220, another roll-to-rule synchronization photo of the present invention, using a mask configured to expose the second subset of microcups, leaving the remaining third subset unexposed. The microcup array is exposed in a lithographic apparatus. In step 222, the microcup array is treated or "washed" with appropriate solvent compositions to remove the exposed portion of the photoresist. In step 220 only the second subset of microcups is exposed, so only the photoresist of the tops of this second subset is removed, so that the tops of the second subset are selectively opened (the third subset is left closed). ). In step 224, the opened second subset of microcups is filled with a second pigment / solvent composition. In step 226, the second subset of opened microcups is sealed to cure as described in step 218.
[166] Thereafter, the remaining photoresist is removed in step 230 and the microcup array is treated or "washed" with appropriate solvent compositions to open the third subset of microcups. Optionally, step 230 may include exposing the remaining photoresist to radiation to aid in removal. In step 232, a third subset of the opened microcups is filled with a third pigment / solvent composition. In step 234, the third subset of opened microcups is sealed to cure as described in step 218.
[167] In step 238, a pre-patterned ITO top conductor film is supplied from the ITO stacked storage device (step 236) and laminated to the top surface of the filled and sealed microcup array. The exemplary process ends by feeding the tricolor EPD microcup array 240 assembled in the form of a continuously sealed EPD array strip to the outside. Microcup array 240 may be supplied to storage, or may continue to be processed in additional successive sequential processing steps. In general, further processing subdivides the array to form individual array portions, which are then packaged to form an EPD product.
[168] Although the present invention has been described with reference to specific embodiments, it will be apparent to those skilled in the art that the present invention may be variously modified or replaced with equivalents thereof without departing from the true spirit and scope of the present invention. In addition, various changes may be made to particular circumstances, materials, compositions, methods, process steps, or steps thereof to suit the purpose, spirit, and scope of the present invention. It is understood that all such changes are within the scope of the claims appended hereto.
[169] For example, the method of the present invention for making microcups may be used to make microcup arrays of liquid crystal displays as well as electrophoretic displays. Similarly, the selective filling, sealing, and ITO lamination methods of the microcups of the present invention may be used in the manufacture of liquid crystal displays.
[170] Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features described herein.

权利要求:
Claims (52)
[1" claim-type="Currently amended] A method of manufacturing a plurality of well-defined structures of at least one electronic device, comprising the step of exposing an image of a radiation sensitive material.
(a) providing a support web;
(b) providing a layer of radiation sensitive composition coated on said support web;
(c) providing a prepatterned photomask having a strip formed as a continuous loop, the photomask pattern projecting an image of the structure by radiation passing through the photomask. Corresponding to at least one of the shapes;
(d) aligning the photomask loop adjacent the support web such that a portion of the photomask loop generally has an orientation parallel to at least a portion of the web;
(e) selectively radiating the radiation sensitive material by passing radiation through the photomask; And
(f) rotating the photomask loop in a synchronized motion relative to the support web, wherein the synchronized motion comprises moving at least a portion of the photomask loop and at least a portion of the web in parallel in substantially the same direction. To, the manufacturing method characterized in that it comprises the rotating step.
[2" claim-type="Currently amended] The method of claim 1,
Rotating the photomask loop comprises moving, during the exposing step, at least a portion of the photomask loop and at least a portion of the web in parallel at substantially the same speed and in substantially the same direction. Manufacturing method.
[3" claim-type="Currently amended] The method of claim 2,
(a) in the step of providing an extended support web, the web has a plurality of conductor lines addressing microcups of at least one display device,
(b) in the step of providing a layer of reflective composition, the composition is a radiation curable material suitable for the structures, the structures being a plurality of microcups disposed as a microcup array of at least one display device,
(c) in the step of providing a pre-patterned photomask, the photomask pattern corresponds to the shape of the plurality of microcups to project the image of the microcups by radiation passing through the photomask; ,
(d) in the step of selectively image exposing the radiation sensitive material, optionally curing the portion of the radiation curable precursor material while leaving the portion of the radiation curable material uncured, wherein the selectively cured A portion corresponds to the plurality of microcups; And
(e) the method comprising selectively removing the uncured portion of the radiocurable material while leaving the selectively cured portion on the web to form the microcup array. Manufacturing method.
[4" claim-type="Currently amended] The method of claim 2,
(a) in the step of providing a supporting web, the web has a plurality of preformed microcups disposed in a microcup array of at least one display device, each microcup having a top opening;
(b) in the step of providing a layer of radiation sensitive composition, the composition is a positive photoresist composition, the layer deposited on the microcup array to seal the plurality of microcup top openings;
(c) in the step of providing a prepatterned photomask, wherein the photomask pattern is configured to project the image of the upper openings of the first microcup subset by radiation through the photomask. Corresponds to the shape of the upper openings of the first selection subset of the plurality of microcups;
(d) in the step of selectively image exposing the radiation sensitive material, selectively exposing a portion of the photoresist layer that is equivalent to the microcup upper openings of the first selected microcup subset; And
(e) said method comprising selectively removing said exposed portion of said photoresist layer to selectively reopen top openings of said first selected microcup subset.
[5" claim-type="Currently amended] The method of claim 4, wherein
The method,
(a) filling the first microcup subset with optionally at least one of a first electrophoretic display pigment / solvent composition and a first liquid crystal composition through the reopened microcup top openings; And
(b) sealing and sealing the reclaimed top openings of the first microcup subset.
[6" claim-type="Currently amended] The method of claim 5,
Following said step of sealing and sealing said reopened top openings of said first microcup subset;
(a) repeating the providing of the photomask, wherein the photomask pattern is adapted to project the image of the upper openings of the second microcup subset by radiation through the photomask. The repeating step corresponding to the shape of the upper opening of the second selection subset of cups;
(b) selectively reopening the upper openings of the second microcup subset by repeating the aligning, selectively exposing the image, rotating, and selectively removing;
(c) filling said second microcupset set with at least one of a second electrophoretic display pigment / solvent composition and a second liquid crystal composition through said reconstructed microcup top openings; And
(d) sealing and sealing the reopened top openings of the second microcup subset.
[7" claim-type="Currently amended] The method of claim 6,
Following said step of sealing and sealing said reopened top openings of said second microcup set,
(a) removing the photoresist layer of the upper openings of at least the third subset of microcups;
(b) filling a third microcup subset with at least one of a third electrophoretic display pigment / solvent composition and a third liquid crystal composition through the reopened microcup top openings; And
(c) sealing and sealing the reopened top openings of the third microcup subset.
[8" claim-type="Currently amended] The method of claim 7, wherein
The method comprises fabricating, on the microcup array, a top stack comprising a plurality of pre-patterned transparent conductor lines addressing microcups of at least one display device. Way.
[9" claim-type="Currently amended] A method of continuously manufacturing a microcup array assembled for at least one display device, the method comprising:
(a) performing the method of claim 3 to form the microcup array on the support web, each having an upper opening;
(b) moving the web to perform at least one subsequent processing step on the microcup array in a generally continuous manner;
(c) filling at least one subset of the microcups through the upper openings with a fluid composition comprising at least one of an electrophoretic display pigment / solvent composition and a liquid crystal display composition, the top openings of the microcups Permanently sealing and sealing the at least one subset; And
(d) stacking an upper stack comprising a plurality of pre-patterned conductor lines addressing microcups of at least one display device on the microcup array, assembled for the at least one display device. Forming a microcup array.
[10" claim-type="Currently amended] The method of claim 9,
The step of filling, sealing and sealing includes filling substantially all of the microcups with a single fluid composition to form an assembled microcup array for at least one monochrome display device. .
[11" claim-type="Currently amended] The method of claim 9,
The step of filling, sealing and sealing comprises performing the process of claim 7 to selectively fill a plurality of microcup subsets with a plurality of different fluid compositions to produce a microcup array assembled for at least one multicolor display device. A manufacturing method comprising forming.
[12" claim-type="Currently amended] In a method of manufacturing a plurality of well-defined structures of at least one electronic device, the structures are arranged equally to the plurality of components of the at least one electronic device, the method comprising the steps of: image exposing a radiation sensitive material In the manufacturing method comprising a,
(a) providing a support web having a surface, wherein
Iii. The support web includes a plurality of components of the at least one electronic device,
Ii. The providing step wherein the components are arranged in a repeating length pattern along the support web;
(b) coating a layer of radiation sensitive composition on the support web;
(c) providing a pre-patterned photomask,
Iii. The photomask has a strip formed as a continuous loop;
Ii. The photomask loop is configured to have a loop surface adjacent to at least a portion of the web substrate,
Iii. Wherein the photomask pattern comprises a plurality of photomask portions each having one of a transparency previously selected for radiation and an opacity previously selected for radiation corresponding to a shape of one of the plurality of structures; Providing step;
(d) aligning the photomask roof surface adjacent to the support web surface in a generally parallel orientation, wherein at least one of the plurality of components is predetermined for at least one of the plurality of photomask portions. Aligning in a spatial relationship of;
(e) selectively image exposing the radiation sensitive material by passing radiation through the photomask; And
(f) moving the photomask roof surface by a synchronous movement relative to the support web surface, wherein the synchronous movement moves the roof surface and the web surface in substantially the same direction with respect to substantially the same distance. Comprising the step of moving, comprising the step of.
[13" claim-type="Currently amended] The method of claim 12,
Moving the photomask roof surface by synchronized movement comprises moving the roof surface and the web surface at substantially the same speed.
[14" claim-type="Currently amended] The method of claim 12,
Moving the photomask roof surface by synchronized movement comprises moving the roof surface and the web surface at a constant relative speed.
[15" claim-type="Currently amended] The method of claim 13,
Moving said photomask roof surface by synchronized movement is generally performed simultaneously with said step of exposing said radiation sensitive material.
[16" claim-type="Currently amended] The method of claim 15,
And the step of moving the photomask roof surface by synchronized movement and the step of exposing the radiation-sensitive material are generally continuous.
[17" claim-type="Currently amended] The method of claim 16,
A process according to claim 1, wherein the step of coating the layer of radiation sensitive composition is generally carried out continuously.
[18" claim-type="Currently amended] The method of claim 15,
In the step of coating a layer of radiation sensitive composition, the layer is
(a) a radiocurable precursor material suitable for the structures; And
(b) one of the photoresist compositions.
[19" claim-type="Currently amended] The method of claim 15,
The step of aligning the photomask loop,
(a) iii. One of the components of the web; And
Ii. Detecting at least one of markers previously formed on the web;
(b) iii. One of said portions of said photomask; And
Ii. Detecting at least one of the markers previously formed on the photomask; And
(c) controlling the movement of at least one of the web and the photomask in response to the detections so that at least one photomask portion forms a predetermined spatial relationship with the at least one photomask portion Way.
[20" claim-type="Currently amended] The method of claim 16,
(a) in the step of providing the support web, the plurality of components of the at least one electronic device comprise a plurality of pre-patterned conductor lines addressing microcups of the electronic display,
(b) in the step of coating the layer of radiation sensitive composition,
Iii. The composition is a radiocurable material suitable for the structures,
Ii. The structures are a plurality of microcups disposed in an array of at least one electronic display,
Iii. The microcups have peripheral microcup walls,
(c) in the step of providing a pre-patterned photomask,
Each of the plurality of photomask portions corresponds to a shape of at least one of the walls of one of the plurality of microcups,
(d) in the step of aligning in a predetermined spatial relationship, comprising aligning at least one of the plurality of conductor lines corresponding to at least one of the plurality of photomask portions corresponding to microcups,
(e) in the step of selectively exposing the radiation-sensitive material, selectively curing a portion of the radiation-curable precursor material while leaving a portion of the radiation-curable precursor material uncured, wherein the selectively cured portion is A process corresponding to the microcup walls.
[21" claim-type="Currently amended] The method of claim 20,
The method, following the step of selectively exposing the radiation sensitive material, selectively removes the uncured portion of the radiation curable precursor material while leaving the selectively cured portion corresponding to the microcup walls. A manufacturing method comprising the step.
[22" claim-type="Currently amended] The method of claim 21,
And wherein said step of selectively removing said uncured portion of said radiocurable precursor material is generally carried out continuously.
[23" claim-type="Currently amended] The method of claim 16,
(a) in the step of providing a supporting web, the web has a plurality of microcup arrays preformed for at least one electronic display, each of the microcups having an upper opening;
(b) in the step of coating the layer of radiation sensitive composition,
Iii. The composition is a photoresist composition that acts positively,
Ii. The coating step deposits the layer on the microcup array and seals and seals the microcup top openings;
(c) in the step of providing a pre-patterned photomask, wherein each of the plurality of photomask portions corresponds to the shape of one of the first selection subset of the plurality of microcup upper openings, with respect to radiation Has a transparency previously selected;
(d) in the step of selectively exposing the radiation sensitive material, selectively exposing a portion of the photoresist layer that is equivalent to the microcup upper openings of the first selected microcup subset. Way.
[24" claim-type="Currently amended] The method of claim 23,
The method further comprises the step of selectively exposing the photoresist layer, followed by selectively removing the exposed portion of the photoresist layer to selectively reopen upper openings of the microcup subset of the first selection. Manufacturing method comprising a.
[25" claim-type="Currently amended] The method of claim 24,
Following the step of selectively removing the exposed portion of the photoresist,
(a) selectively selecting said first microcup subset through said reopened microcup upper openings;
Iii. First electrophoretic display pigment / solvent composition; And
Ii. Filling with at least one of the first liquid crystal compositions; And
(b) permanently sealing and sealing the reopened top openings of the first microcup subset.
[26" claim-type="Currently amended] The method of claim 25,
Following said step of sealing and sealing said reopened top openings of said first microcup subset,
(a) repeating the photomask providing step by providing a second photomask comprising photomask portions corresponding to the shape of the top openings of the second selection subset of microcups;
(b) repeating the alignment, shifting, optional image exposure, and optional removal steps with respect to the second photomask and the second microcup subset, wherein the upper opening of the second microcup subset is Selectively reopening them;
(c) selectively selecting said second microcup subset through said reopened microcup upper openings.
Iii. Second electrophoretic display pigment / solvent composition; And
Ii. Filling with at least one of the second liquid crystal compositions; And
(d) sealing and sealing the reopened top openings of the second microcup subset.
[27" claim-type="Currently amended] The method of claim 26,
The step of providing a web includes providing a microcup array, the array having at least a third subset of microcups different from the first and second subsets,
Following said step of sealing and sealing said reopened top openings of said second microcup subset,
(a) removing the photoresist layer at least against upper openings of the third subset of microcups;
(b) drawing the third microcup subset through the reopened microcup upper openings;
Iii. Third electrophoretic display pigment / solvent composition; And
Iii. Filling with at least one of the third liquid crystal compositions; And
(c) sealing and sealing the reopened top openings of the third microcup subset.
[28" claim-type="Currently amended] The method of claim 27,
The method includes stacking an upper stack on the sealed microcup array, the upper stack having a plurality of pre-patterned conductor lines that address microcups of at least one display device. Manufacturing method characterized by the above-mentioned.
[29" claim-type="Currently amended] The method of claim 28,
The method includes depositing an adhesive layer between the sealed microcup array and the pre-patterned conductor lines by coating and lamination.
[30" claim-type="Currently amended] An apparatus for fabricating a plurality of well-defined structures of at least one electronic device by image exposing a layer of radiation sensitive material coated on a support web,
(a) a web drive mechanism for the support web for movably guiding the support web;
(b) a prepatterned photomask having a strip formed as a continuous loop;
(c) a photomask alignment mechanism associated with the photomask, the photomask loop being installed adjacent to the web such that a portion of the photomask loop generally has an orientation parallel to at least a portion of the web. The photomask alignment mechanism, aligning adjacent to the photomask;
(d) a photomask drive mechanism associated with the photomask that rotates the photomask loop, the photomask drive mechanism synchronized with the web drive mechanism to rotate the photomask loop by a synchronous movement relative to the support web. And wherein the synchronizing movement comprises moving at least a portion of the photomask loop and at least a portion of the web in parallel in substantially the same direction;
(e) the photomask pattern corresponding to the shape of at least one of the structures to project an image of the structure by radiation passing through the photomask; And
and (f) a radiation source co-aligned with said photomask and said web to pass radiation through said photomask to selectively image expose said radiation sensitive material.
[31" claim-type="Currently amended] The method of claim 30,
Said synchronous movement of said synchronizable photomask driving mechanism comprises moving at least a portion of said photomask loop and at least a portion of said web in parallel at substantially the same speed.
[32" claim-type="Currently amended] The method of claim 31, wherein
(a) the support web comprises a plurality of conductor lines addressing microcups of at least one display device;
(b) the layer of radiation sensitive composition is a radiation curable material suitable for the structures, the structures being a plurality of microcups disposed as a microcup array of at least one display device; And
(c) the photomask pattern selectively exposes the precursor material by an image of the microcups projected by radiation from the radiation source passing through the photomask, leaving a portion of the precursor material without curing. And correspondingly to the shape of the plurality of microcups, wherein the selectively cured portion corresponds to the plurality of microcups to selectively cure a portion of the precursor material.
[33" claim-type="Currently amended] The method of claim 32,
A solvent installed adjacent to the web to provide at least one solvent that removes the uncured portion of the precursor material while leaving the selectively cured portion on the web to form the microcup array on the web. A manufacturing apparatus further comprising an application mechanism.
[34" claim-type="Currently amended] The method of claim 31, wherein
(a) the support web has a plurality of preformed microcups disposed in a microcup array of at least one display device, each of the microcups having an upper opening;
(b) the layer of radiation sensitive composition is a positively acting photoresist composition deposited on the microcup array to seal the plurality of microcup top openings;
(c) the photomask is a first photomask having a first pattern; And
(d) the first photomask pattern selectively exposes the photoresist layer by an image of the upper openings of the first microcup subset by radiation passing through the first photomask, thereby providing the photoresist. The upper portion of the first selection subset of the plurality of microcups to expose a portion of the photoresist layer that is equivalent to the upper openings of the microcup subset of the first selection while leaving a portion of the layer unexposed An apparatus corresponding to the shape of the openings.
[35" claim-type="Currently amended] The method of claim 34, wherein
Provide at least one solvent to remove the exposed portions of the photoresist layer while leaving the unexposed portions in the microcup array to selectively reopen the top openings of the first selected microcup subset. And a solvent application mechanism installed adjacent to the web.
[36" claim-type="Currently amended] 36. The method of claim 35 wherein
(a) adjacent the web to fill the first microcup subset with at least one of a first electrophoretic display pigment / solvent composition and a first liquid crystal display composition through the reopened microcup top openings A first microcup filling mechanism installed; And
(b) a first microcup sealing mechanism installed adjacent to the web to seal and seal the reopened top openings of the first microcup subset.
[37" claim-type="Currently amended] The method of claim 36,
(a) a second pre-patterned photomask having a second pattern;
(b) a second photomask alignment mechanism associated with the second photomask, wherein the second alignment mechanism aligns the second photomask loop adjacent to the web such that a portion of the photomask loop is at least part of the web. The second photomask alignment mechanism installed adjacent the web to have a generally parallel orientation with respect to a portion;
(c) a second photomask driving mechanism associated with said second photomask for rotating said second photomask loop, said second photomask driving mechanism moving said second photomask loop in synchronization with said support web. And wherein the synchronizing movement comprises moving at least a portion of the second photomask loop and at least a portion of the web in parallel at substantially the same speed. 2 photomask drive mechanism;
(d) a second radiation source co-aligned with said second photomask and said web so as to selectively expose said radiation sensitive material by passing radiation through said second photomask;
(e) selectively exposing the photoresist layer by an image of the upper openings of the second microcup subset, leaving a portion of the photoresist layer unexposed while remaining in the microcup subset of the second selection. The second photomask pattern corresponding to the shape of the top openings of the second selection subset of the plurality of microcups to expose a portion of the photoresist layer that is equivalent to the top openings;
(f) providing at least one solvent to remove the exposed portion of the photoresist layer while leaving the unexposed portion on the microcup array, thereby providing top openings of the microcup subset of the second selection. A second solvent application mechanism installed adjacent said web to selectively reopen;
(g) adjoining the web such that the second microcup subset is optionally filled with at least one of a second electrophoretic display pigment / solvent composition and a second liquid crystal composition through the reopened microcup top openings. A second microcup filling mechanism installed; And
(h) a second microcup sealing mechanism installed adjacent to the web to seal and seal the reopened top openings of the second microcup subset.
[38" claim-type="Currently amended] The method of claim 37,
(a) providing the at least one solvent to remove the photoresist layer on the third subset of the microcups of the microcup array to reopen the top openings of the third microcup subset; A third solvent application mechanism installed adjacent to the;
(b) disposed adjacent the web to fill the third microcup subset with at least one of a third electrophoretic display pigment / solvent composition and a third liquid crystal composition through the reopened microcup top openings; A third microcup filling mechanism;
(c) a third microcup sealing mechanism disposed adjacent the web to seal and seal the reopened top openings of the third microcup subset.
[39" claim-type="Currently amended] The method of claim 38,
Further comprising a lamination mechanism installed adjacent to the web to adhere the stack onto the microcup array of the upper stack,
And wherein the upper stack has a plurality of pre-patterned conductor lines that address microcups of at least one display device.
[40" claim-type="Currently amended] The method of claim 2,
And said conductor lines transmit visible light.
[41" claim-type="Currently amended] The method of claim 8,
And said conductor lines transmit visible light.
[42" claim-type="Currently amended] The method of claim 20,
And said conductor lines transmit visible light.
[43" claim-type="Currently amended] The method of claim 28,
And said conductor lines transmit visible light.
[44" claim-type="Currently amended] The method of claim 32,
And the conductor lines transmit visible light.
[45" claim-type="Currently amended] The method of claim 39,
And the conductor lines transmit visible light.
[46" claim-type="Currently amended] And exposing the image through a moving photomask in synchronization with the moving web substrate.
[47" claim-type="Currently amended] The method of claim 46,
And the web substrate has a conductor layer coated with a radiation sensitive material on the plastic substrate.
[48" claim-type="Currently amended] The method of claim 47,
The conductor layer is a photolithographic method, characterized in that the polyethylene terephthalate (PET), polyethylene naphthate (PEN) or ITO on polycarbonate.
[49" claim-type="Currently amended] The method of claim 47,
And the radiation sensitive material is a positive photoresist.
[50" claim-type="Currently amended] The method of claim 47,
And the web substrate is ITO / PET coated with a positive photoresist.
[51" claim-type="Currently amended] The method of claim 49,
And developing the positive photoresist after exposure, wherein the conductor layer / plastic substrate is etched to expose the individual patterns.
[52" claim-type="Currently amended] The method of claim 51, wherein
Removing the photoresist.

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同族专利:

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公开号 | 公开日

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JP2004525404A|2004-08-19|

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US20030152849A1|2003-08-14|

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CN1237387C|2006-01-18|

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JP4298294B2|2009-07-15|

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CA2437411A1|2002-08-22|

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WO2002065215A2|2002-08-22|

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TW556044B|2003-10-01|

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US6906779B2|2005-06-14|

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WO2002065215A3|2003-10-09|

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WO2002065215A8|2003-11-13|

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EP1368710A2|2003-12-10|

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CN1371023A|2002-09-25|

---

KR100918600B1|2009-09-25|

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MXPA03007265A|2004-06-30|

---

AU2002244078A1|2002-08-28|

引用文献:

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公开号 | 申请日 | 公开日 | 申请人 | 专利标题

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法律状态:
2001-02-15|Priority to US09/784,972

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2001-02-15|Priority to US09/784,972

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2002-02-14|Application filed by 사이픽스 이미징, 인코포레이티드

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2002-02-14|Priority to PCT/US2002/004967

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2003-12-03|Publication of KR20030091988A

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2009-09-25|Application granted

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2009-09-25|Publication of KR100918600B1

优先权:

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申请号 | 申请日 | 专利标题

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US09/784,972|2001-02-15|

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US09/784,972|US6933098B2|2000-01-11|2001-02-15|Process for roll-to-roll manufacture of a display by synchronized photolithographic exposure on a substrate web|

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PCT/US2002/004967|WO2002065215A2|2001-02-15|2002-02-14|Process for roll-to-roll manufacture of a display by synchronized photolithographic exposure on a substrate web|