• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The present invention is directed to a pressure-sensitive (meth) acrylic adhesive composition and a (meth) acrylic pressure-sensitive adhesive tape having excellent adhesion and solvent saving characteristics (reduction of amount of solvent to be used) at low cost. The (meth) acrylic pressure sensitive adhesive composition comprising a (meth) acrylic based copolymer, a hydrocarbon solvent and an adhesive.
    公开号:BE1017975A3
    申请号:E2008/0060
    申请日:2008-01-31
    公开日:2010-02-02
    发明作者:Kazuyuki Yagura；Hiroshi Wada；Hironori Tamai
    申请人:Nitto Denko Corp；
    IPC主号:
    专利说明:

    Pressure-sensitive adhesive composition based on (meth) acrylic and pressure-sensitive adhesive tape based on (meth) acrylic
    Technical area
    The present invention relates to a pressure-sensitive adhesive composition based on (meth) acrylic and a pressure-sensitive adhesive tape based on (meth) acrylic, which have excellent performance in terms of adhesiveness and solvent economy ( reduction of the amount of solvent to use).
    Background technique
    There are various methods for producing a pressure sensitive adhesive composition based on (meth) acrylic. Methods include solution polymerization, emulsion polymerization, ultraviolet (radiation) polymerization, and bulk polymerization. All polymerization processes, except for solution polymerization, make it possible to produce the composition without the use of a solvent. However, the actual production process or the properties of the resulting adhesive composition have disadvantages and advantages so that the solution polymerization still predominates. Recently, the range of applications of a pressure-sensitive adhesive agent has been extended and the trend stimulates the requirement for improvement of properties and functions. To meet the requirement, functions are added by copolymerization with various monomers, production of high molecular weight polymers and additives such as an adhesive resin. However, it is known that the viscosity increases in proportion to the power of 3.4 of a molecular weight as the molecular weight is increased to achieve high functionalization. As a result, it is inevitable to increase the solvent content in an adhesive agent to apply the adhesive agent to a carrier.
    On the other hand, because of the environmental problems of recent years, the solvent economy (reduction of the amount of solvent to be used) is recommended even in a pressure-sensitive adhesive composition based on (meth) acrylic. An adhesive agent containing a high concentration (meth) acrylic copolymer in an effort to promote solvent economy becomes very viscous and faces difficulties during the coating process. On the other hand, it is difficult to meet both solvent economy and adhesion characteristics, because a (meth) acrylic base copolymer of degraded molecular weight is, in terms of properties, less than a ribbon. adhesive at high temperature.
    A photosensitive adhesive agent or an adhesive agent polymer solution is disclosed for the purpose of reducing the amount of solvent to be used. It comprises a polymer based on acrylic or methacrylic acid, which has a weight average molecular weight of 5000 to 50,000 and 2.2 to 10 double bonds and 1 to 20 acid groups on average for a weight average molecular weight of 10,000 on the side chain, and a photosensitizer (patent document 1).
    A surface-structured radiation-curable silicon (PSA) pressure-sensitive adhesive agent and a PSA-coated sheet material are also disclosed (Patent Document 2).
    Also disclosed is a pressure-sensitive adhesive agent which is prepared by polymerizing a pressure-sensitive adhesive monomer and the oligomeric reaction product of the aforesaid pressure-sensitive adhesive in a solvent in the form of a pressure-sensitive adhesive. supercritical, semi-supercritical or subcritical fluid (patent document 3). Although the adhesives (adhesive agents) described in Patent Document 1 and Patent Document 2 may reduce the amount of solvent to be used, they fail to meet the properties and functions that will be required in the future. The pressure-sensitive adhesive agent described in Patent Document 3 requires polymerization in a supercritical, semi-supercritical or subcritical fluid state and, therefore, the production process is complex. This makes the cost of production high and the adhesive composition and the adhesive tape can not be produced at low cost.
    Patent Document 1: Japanese Unexamined Patent Publication No. 57-141471
    Patent Document 2: Japanese Unexamined Patent Publication No. 6-508862
    Patent Document 3: Japanese Unexamined Patent Publication No. 2000-129241 Description of the Invention Problems to be Resolved by the Invention
    The present invention has solved the above problems and one of its aims is to provide a pressure-sensitive adhesive composition based on (meth) acrylic and a pressure-sensitive adhesive tape based on (meth) acrylic, which exhibit a excellent adhesiveness and excellent solvent economy (reduction of the amount of solvent to use) at low cost.
    The present inventors have devoted themselves to the study in the light of the present situation as described above and have discovered the process for producing a (meth) acrylic pressure-sensitive adhesive composition having excellent properties. adhesiveness and solvent economy, by regulating the composition and the weight average molecular weight of a (meth) acrylic based copolymer and also by using a specific solvent and an adhesive.
    Specifically, the present invention relates to a (meth) acrylic pressure sensitive adhesive composition comprising a (meth) acrylic based copolymer, a hydrocarbon solvent and an adhesive, wherein the (meth) acrylic based copolymer has a weight weight average molecular weight of from 350,000 to 490,000 and also contains, as monomeric components, an alkyl (meth) acrylate with an alkyl group having 2 to 18 carbon atoms and a vinyl compound having at least one acid group, and the The vinyl compound content is in a range of 0.5 to 5% by weight, based on all the monomer components, and the tackifier is a rosin derivative having a softening point of 90 to 150 ° C and an index of acidity of 8 to 16 mg KOH / g.
    When the weight average molecular weight of the (meth) acrylic based copolymer is less than 350,000, the required adhesiveness, heat resistance and flexibility are not achieved. When the weight average molecular weight exceeds 490,000, the amount of solvent in the adhesive composition can not be completely reduced due to the high viscosity.
    The (meth) acrylic-based copolymer contains, as monomeric components, an alkyl (meth) acrylate with an alkyl group having 2 to 18 carbon atoms and a vinyl compound having at least one acidic group. The combination use of the above two monomer components provides a (meth) acrylic pressure-sensitive adhesive composition which has excellent tack and solvent-saving properties (reducing the amount of solvent to be used). When the carbon number of the alkyl group in the alkyl (meth) acrylate is outside the above range, the properties as a pressure-sensitive adhesive agent are degraded. It is necessary that the vinyl compound content is in a range of 0.5 to 5% by weight based on all the monomer components. When the vinyl compound content is less than 0.5% by weight, the cohesion force declines and, consequently, the performance of the adhesive agent declines, whereas, when it exceeds 5% by weight, the viscosity increases. and, therefore, a large amount of solvent is needed.
    In the present invention, a rosin derivative is used as an adhesive, which has a softening point of 90 to 150 ° C and an acid number of 8 to 16 mg KOH / g. The use of a tackifier enhances adhesion characteristics to adhesion retardant materials, such as polyethylene and polypropylene. The adhesive is exemplified by a terpene resin, a coumarone-indene resin and a hydrocarbon resin as well as by the rosin derivative, but, given the compatibility with the (meth) acrylic-based copolymer and adhesiveness, it is necessary to use the rosin derivative with the aforementioned physical properties.
    When the softening point of the rosin derivative is less than 90 ° C, the adhesive agent is softened at elevated temperature and, as a result, the heat resistance of the pressure-sensitive adhesive layer declines, whereas when the softening point exceeds 150 ° C, the adhesive agent is cured and, as a result, the adhesiveness to the irregular surface of the adhesive agent declines.
    The acid number of the rosin derivative is important for the solvent economy. When the acid number of the rosin derivative is less than 8 mg KOH / g, the compatibility with the (meth) acrylic base copolymer having the acidic group is degraded and, consequently, the adhesiveness of the adhesive layer. pressure sensitive declines. When the acid number exceeds 16 mg KOH / g, the rosin derivative and the (meth) acrylic-based copolymer are likely to become entangled due to the interaction between a carboxyl group of the first and an acid group of the second and, as a result, the viscosity of the adhesive composition increases, which complicates the uniform coating of the composition on a support.
    In the (meth) acrylic pressure-sensitive adhesive composition of the present invention, it is preferred that the solids content is in a range of 36 to 60% by weight and the viscosity is 30 Pa.s or less. at 30 ° C. By adjusting the solids content and viscosity in the above range, adhesion characteristics, solvent saving property and coating property are enhanced.
    The (meth) acrylic pressure-sensitive adhesive tape of the present invention comprises a backing and a pressure sensitive adhesive layer which is formed by coating the (meth) acrylic pressure-sensitive adhesive composition onto the support.
    It is preferred that the pressure-sensitive adhesive layer have a haze value of 5 or less at 50 μm in thickness. Compatibility between the (meth) acrylic based copolymer and the rosin derivative is adjusted by the haze value. It is not preferred that the compatibility between the (meth) acrylic based copolymer and the rosin derivative be poor, since the pressure sensitive adhesive layer is susceptible. to be sensitive to a diachronic variation. The refractive index of the (meth) acrylic copolymer and that of the rosin derivative are different and the (meth) acrylic copolymer or rosin derivative agglutinates to have a refractive index greater than the length of the rosin. wave of light when compatibility is poor, leading to a high haze value. When the compatibility is good, the (meth) acrylic-based copolymer and the rosin derivative are not likely to clump together and, as a result, the haze value becomes low. The sail value varies depending on the thickness of the pressure-sensitive adhesive layer. When the haze value is 5 or less to 50 μm thick of the pressure-sensitive adhesive layer, a common thickness, the compatibility of the (meth) acrylic-based copolymer and the rosin derivative is good, and as a result the pressure-sensitive adhesive layer tends to undergo diachronic variation.
    It is preferred that the tension of the pressure-sensitive adhesive layer be 5 N / cm 2 or less when the layer is stretched by 300% in a tension / elongation test and, more preferably, from 3 to 4.5 N / cm 2 . Because the requirement for adhesive tape is becoming more stringent from year to year, a molecular weight above a certain level is required to meet the requirement. Polymers having low molecular weight have problems such as heat resistance and low crosslinking density, are hard and are not suitable for practical use in many cases. Although dynamic viscoelasticity, glass transition temperature, degree of swelling, gel content and the like have been used as indicators for measuring the crosslinking density and physical properties of a polymer, they do not necessarily indicate the Physical properties under conditions where an adhesive tape is actually used. For example, dynamic viscoelasticity demonstrates certain behaviors in physical properties such as temperature and frequency. However, this is due to minimal deformation and is not consistent with the deformation behavior when using the adhesive tape. The present inventors have found that the tension displayed with a 300% stretch in a tension / elongation test served as an indicator of the behavior when using the adhesive tape and that the pressure-sensitive adhesive layer exhibited excellent results. properties when the tension was 5 N / cm2 or less. When the tension exceeds 5 N / cm 2 at 300% stretching, the adhesive strength tends to be lower, because compliance due to deformation of the pressure sensitive adhesive layer against an uneven surface, such as a urethane foam becomes weak.
    It is also preferred that the amount of solvent remaining in the pressure-sensitive adhesive layer is 3000 ppm or less in a residual solvent test. When the amount of solvent exceeds 3000 ppm, the solvent odor becomes stronger and may cause discomfort.
    Best embodiment of the invention
    The (meth) acrylic based copolymer used in the present invention has a weight average molecular weight of 350,000 to 490,000 and also contains as monomeric components an alkyl (meth) acrylate with an alkyl group having 2 to 18 carbon atoms. carbon and a vinyl compound having at least one acidic group.
    Examples of the alkyl (meth) acrylate that may be mentioned are ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, t (meth) acrylate and the like. butyl, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate and dodecyl (meth) acrylate. These alkyl (meth) acrylates can be used alone or in combination.
    Examples of the vinyl compound include (meth) acrylic acid, itaconic acid, 2- (meth) acryloyloxypropyl sulfonate and (meth) acryloyloxyethyl phosphate. These compounds can be used alone or in combination. It is necessary that the vinyl compound is contained in an amount of 0.5 to 5% by weight, preferably 1 to 3% by weight, based on all of the monomer components.
    As examples of the other monomer component, mention may be made of monomers containing a hydroxyl group, such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4 (meth) acrylate and the like. hydroxybutyl and hydroxyhexyl (meth) acrylate; a nitrogen-containing (meth) acrylate, such as (meth) acrylamide and acryloyl-morphorine; and polar monomers, such as vinyl acetate. These monomers can be used alone or in combination. These monomers are effective in increasing the cohesive strength of the adhesive agent. The other monomer component is contained in an amount of 100 parts by weight or less, preferably 50 parts by weight or less, based on 100 parts by weight of the alkyl (meth) acrylate.
    It is also permissible to use a monomer component which forms a polymer having a high glass transition temperature, such as (meth) acrylonitrile, styrene, vinylidene chloride and vinyl propionate. It is preferred that the monomer component be used in an amount of 100 parts by weight or less, preferably 50 parts by weight or less, based on 100 parts by weight of the alkyl (meth) acrylate. It is also preferred that the monomer component be added in a range such that the tension is 5 N / cm 2 or less at 300% stretching in a pressure / elongation test of the pressure-sensitive adhesive layer because the component monomer hardens the (meth) acrylic copolymer.
    It is necessary that the weight average molecular weight of the (meth) acrylic-based copolymer is in the range of 350,000 to 490,000, preferably 380,000 to 480,000, more preferably 400,000 to 480,000, more preferably from 400,000 to 460,000, and much better still, from 410,000 to 450,000.
    In the present invention, as an adhesive to be used, there may be mentioned a rosin derivative having a softening point of 90 to 150 ° C and an acid number of 8 to 16 mg KOH / g.
    The rosin derivative is derived from rosins and has the aforementioned acid number. Specific examples of these include rosin esters, phenol-modified rosins and their esters. Examples of rosins include gum rosin, wood rosin, and tall oil rosin; stabilized rosin and polymerized rosin prepared by disproportionation or hydrogenation of rosin; and an unsaturated acid-modified rosin prepared by modifying rosin with maleic acid, fumaric acid, (meth) acrylic acid or the like.
    The rosin esters are prepared by esterification of the rosins with a polyvalent alcohol. Esterification uses exactly the same conditions as those in which rosin and polyvalent alcohol are commonly esterified. For example, it is performed by heating the rosins and the polyhydric alcohol at a temperature of 150 to 300 ° C under atmospheric pressure of an inert gas, removing the water generated by the reaction out of the system. The ratio of the rosins and the polyvalent alcohol to be loaded is adjusted correctly so that the rosin esters obtained have the target acid number. In general, a polyvalent alcohol having hydroxyl groups in an amount of about 0.5 to 1.5 times equivalent based on the equivalent of carboxyl groups of rosins should be used.
    As examples of the polyvalent alcohol, mention may be made of bivalent alcohols, such as ethylene glycol, diethylene glycol, propylene glycol and neopentyl glycol; trivalent alcohols, such as glycerine, trimethylolethane and trimethylolpropane; tetravalent alcohols, such as pentaerythritol and diglycerin; and hexavalent alcohols, such as dipentaerythritol. These alcohols can be used alone or in combination.
    Although the reaction does not necessarily require an esterification catalyst, an acidic catalyst such as acetic acid and para-toluenesulfonic acid may be used; a hydroxide of an alkali metal, such as lithium hydroxide; a hydroxide of an alkaline earth metal, such as calcium hydroxide; and a metal oxide, such as calcium oxide and magnesium oxide, to shorten the reaction time.
    Examples of phenol-modified rosins and esters include phenol-added rosins; rosin added with phenol and subsequently esterified; and so-called rosin-modified phenolic resins made by reacting phenol resole resins with rosins and their esters. Phenol-modified rosin esters may be prepared under the same conditions as those for rosin esters, using the same polyvalent alcohol and a catalyst.
    It is preferred to use polymerized rosin esters among rosin derivatives because of adhesiveness to delayed adhesion adhesive materials such as polyethylene and polypropylene.
    It is preferred that the softening point of the rosin derivative is in a range of 90 to 140 ° C, more preferably 100 to 140 ° C.
    It is preferred that the acid number of the rosin derivative is in a range of 10 to 16 mg KOH / g, more preferably 12 to 16 mg KOH / g.
    It is preferred that the amount of the rosin derivative to be added is in a range of 5 to 60 parts by weight, more preferably 10 to 50 parts by weight, based on 100 parts by weight of the (meth) acrylic copolymer.
    The solvent used for the methacrylic pressure-sensitive adhesive composition of the present invention is an aliphatic, alicyclic or aromatic hydrocarbon solvent. These solvents can be used alone or in combination. The hydrocarbon solvent is adsorbable on activated charcoal and, therefore, is convenient for use in a solvent recovery device. It is also excellent in terms of profitability. The present invention does not use any solvent other than the hydrocarbon solvent. The reasons are that ketone-based solvents, such as ethyl acetate and methyl ethyl ketone, and alcohol-based solvents, such as methanol and ethanol, present a risk of explosion when a water desorption solvent recovery device is used and has a cost problem because the solvents are not able to be adsorbed in activated carbon. Hydrophilic solvents present the risk of causing contamination of the water.
    Examples of the aliphatic hydrocarbon solvent include hexane, heptane, octane, a cactus solvent and white spirit.
    Examples of the alicyclic hydrocarbon solvent include cyclohexane, cyclohexene, cycloheptane, cyclooctane and cyclooctene.
    Examples of the aromatic hydrocarbon solvent include benzene, toluene and xylene.
    It is preferred to use a mixed solvent of toluene and aliphatic hydrocarbon or toluene because of the cost, the efficiency of a solvent recovery device and the environmental load, in particular. As the molecular weight of a polymer becomes higher, the viscosity becomes larger and the coating property becomes poorer, requiring more solvent. As a result, it is necessary to remove the molecular weight of the polymer. In general, a chain transfer agent is used to adjust the molecular weight of a polymer, but the chain transfer agent contains mercaptan-based sulfur in many cases, and its use is limited to the field of the devices. e. There are some solvents that have a high chain transfer constant, such as isopropyl alcohol, but it is not preferred to use these solvents because of the risk of explosion, as noted above, in a solvent recovery device and also the risk of generating an aldehyde due to oxidation under the effect of heat in a drying process. On the other hand, it is preferred to use toluene because the chain transfer constant is relatively high, which makes it possible to adjust the molecular weight of a polymer in a targeted range and also to overcome the risk that presents alcohol-based solvents. When a mixed solvent of toluene and aliphatic hydrocarbon is used, it is preferred that the amount of the aliphatic hydrocarbon to be used is 40 parts by weight or less, preferably 30 parts by weight or less, relative to 100 parts by weight of toluene to adjust the molecular weight of a polymer in a targeted range.
    It is preferred to add the hydrocarbon solvent in an amount such that the solids content is 36 to 60% by weight, preferably 36 to 52% by weight, more preferably 40 to 50% by weight, and most preferably 42 to 48% by weight. % by weight, and still more preferably 44 to 48% by weight. The adhesive composition of the present invention has a high concentration, but a low viscosity at the same time, compared to conventional adhesive compositions and this allows the reduction of the solvent content.
    The (meth) acrylic based copolymer is prepared by solution polymerization of monomeric components in the hydrocarbon solvent. The synthesis process is not particularly limited and any methods are available, such as polymerization by charging all the monomers in a reactor or polymerization at the same time, by dropwise loading the monomers in stages. The polymerization time is not particularly limited, but is usually 2 to 24 hours.
    A polymerization initiator may be added to the solution at one time or dropwise. Examples of the polymerization initiator include peroxides, such as hydrogen peroxide, benzoyl peroxide, and t-butyl peroxide. Single use is preferred, but it can be combined with a reducing agent to produce a redox polymerization initiator. Examples of the reducing agent include ionizable salts, such as sulfite, hydrogen sulfite, iron salt, copper salt and cobalt salt; amines such as triethanolamine; and reducing sugars, such as aldose and ketosis. An azo compound is also a preferred polymerization initiator and, as examples thereof, there may be mentioned 2,2'-azobis-2-methyl propioamidinate, 2,2'-azobis-2-valeronitrile, 4-dimethyl, 2,2'-azobis-N, N'-dimethylene isobutyl amidamide, 2,2'-azobisisobutylonitrile and 2,2'-azobis-2-methyl-N- (2-hydroxyethyl) ) propionamide. The polymerization initiators can be used in combination.
    The amount of polymerization initiator to be added is about 0.001 to 5 parts by weight based on 100 parts by weight of monomer components.
    The polymerization temperature is about 30 to 100 ° C in the case of a single polymerization initiator, while the initiation temperature is about 5 to 60 ° C in the case of a redox polymerization initiator . It is not necessary to maintain the polymerization temperature constant, but there may be some cases where the system has to be cooled, because the temperature rises because of the heat to be generated as the polymerization progresses. The atmosphere in the polymerization reactor during the polymerization is not particularly limited, but it is preferred to replace the atmosphere with an inert gas, such as nitrogen gas, to easily conduct the polymerization.
    It is preferred that the methacrylic pressure-sensitive adhesive composition prepared in this manner has a solids content of 36 to 60% by weight and also a viscosity of 30 Pa.s or less at 30 ° C. When the solids content is less than 36% by weight, the reduction of a solvent is not sufficient, whereas, when it exceeds 60% by weight, the concentration becomes high and the practice of coating tends to be difficult. . When the viscosity exceeds 30 Pa.s at 30 ° C, the practice of coating on a substrate tends to be difficult. When the viscosity is too low, repellency tends to occur when coating the composition onto a support. Because of the foregoing reasons, it is preferred that the viscosity at 30 ° C be 5 Pa.s or more, more preferably in the range of 10 to 28 Pa.s, more preferably 15 to 28 Pa. .s and much better still, from 20 to 26 Pa.s.
    It is preferred that the (meth) acrylic pressure-sensitive adhesive composition of the present invention contain a crosslinking agent as well.
    Examples of crosslinking agents that may be mentioned are crosslinking agents of epoxy, isocyanate and aziridine type.
    The amount of crosslinking agent to be added is about 0.01 to 5 parts by weight based on 100 parts by weight of the (meth) acrylic based copolymer, although it varies depending on the use and type of crosslinking agent.
    Additives such as a pigment, a dye, a flame retardant, a heat stabilizer and a plasticizer can also be added to the (meth) acrylic pressure-sensitive adhesive composition.
    The (meth) acrylic pressure-sensitive adhesive tape of the present invention is prepared from a carrier and a pressure-sensitive adhesive layer which is formed by coating the pressure-sensitive adhesive composition based on of methacrylic on the support.
    The support is not particularly limited. Examples of this include films such as polyester film, polyvinyl chloride film, polyethylene film, polypropylene film, polyphenylene sulfide film, and the like. a polyimide film; papers such as high quality paper, kraft paper and stretch paper nonwoven fabrics, metal sheets and laminates thereof. The surface of the support can undergo an exfoliation treatment with silicone and the like.
    The coating process is not particularly limited and a current method can be used. For example, the methacrylic pressure-sensitive adhesive composition is coated on the carrier using a suitable coating device, such as a bar coater, a spin coating device, a coater roller coating and an applicator, the crosslinking is formed under the effect of heat so as to cure the (meth) acrylic-based copolymer and the solvent is removed, so that a pressure-sensitive adhesive layer can be formed .
    The thickness of the pressure-sensitive adhesive layer is not particularly limited, but is usually in a range of 25 to 100 μιη.
    The (meth) acrylic pressure-sensitive adhesive tape prepared in this manner has excellent low temperature flexibility, excellent high temperature stability and excellent adhesion characteristics, such as tackiness to an irregular surface.
    EXAMPLES
    Hereinafter, the constitution and effect of the present invention will be described as specific examples. In addition, the evaluation articles in the examples are measured as follows. Measurement of the weight average molecular weight
    The weight average molecular weight is measured by a gel permeation chromatography method and calculated in terms of polystyrene conversion. The detailed measuring conditions are as follows: GPC equipment: HLC-8120GPC manufactured by Tosoh
    Corporation column: 6.0 mm ID x 150 mm, TSKgel Super HM-H / H4000 / H3000 / H2000 flow rate: 0.6 ml / min concentration: 0.1% by weight injection volume: 20 μΐ
    column temperature: 40 ° C
    Eluent: THF
    Measurement of the softening point
    The softening point of the adhesive is measured by a ring and ball method according to JIS K5601.
    Measurement of the acid number The acid number of the adhesive is measured by a method according to JIS K5902.
    Measurement of solids content 2-3 g of the acrylic pressure-sensitive composition are placed in an Al cup, weighed and allowed to stand for 2 hours in a dryer at 120 ° C. Then, the cup is removed, cooled to 23 ° C for 1 hour and weighed. The solids content is evaluated from the weight variation before and after drying.
    Measurement of the sailing value
    Each of the acrylic-based pressure-sensitive compositions of Examples 1-5 and Comparative Examples 1-7 were coated on a non-stick paper sheet (NS-50 manufactured by Lintec Corporation) using a cooker applicator, and dried and crosslinked. hardened at a coating speed of 15 m / min to form a pressure-sensitive adhesive layer (thickness 50 μπι). Then, the pressure-sensitive adhesive layer is peeled off the release paper. The haze value of the pressure sensitive adhesive layer is calculated by the following equation using a diffuse transmittance and a transmittance of a total light beam. The diffuse transmittance and transmittance of a total light beam are measured according to JIS K7136 using a HMISO sail indicator (manufactured by Murakami Color Research Laboratory).
    Sail value (%) = (diffuse transmission factor / transmission factor of a total light beam) x 100 Viscosity measurement
    The viscosity of the methacrylic pressure-sensitive adhesive composition is measured at 30 ° C using a BH-type viscometer (VISCOMETER manufactured by TOKMEC, INC).
    Measuring adhesive force
    The prepared (meth) acrylic pressure-sensitive adhesive tape is cut into 20 mm x 20 mm and adhered to an adhesive material (SUS304 or ether-based urethane foam) by printing a single movement of va-and - comes to a roll of 2 kg. The adhesive material is allowed to stand for 30 minutes under environmental conditions of 23 ° C and 50% RH and measured. The adhesive strength at 180 pulling is measured by pulling the tape at a 300mm / min. Crosshead speed using an AG1-kNG autograph (manufactured by Shimadzu Corporation).
    Measurement of the remanent magnetization
    The prepared (meth) acrylic pressure-sensitive adhesive tape is cut into 10 mm x 10 mm and adhered to a bakelite plate (10 mm x 20 mm). Displacement at 80 ° C under a load of 500 g is measured. Residual solvent test
    The (meth) acrylic pressure-sensitive adhesive tape prepared was cut into pieces measuring 10 mm x 10 mm, weighed and glued on an aluminum foil. The sample is placed in a 21.5 ml vial-type container and sealed. The flask is heated at 150 ° C for 10 minutes using a headspace autosampler (HP7694 manufactured by Hewlett Packard). 1.0 ml of the heated gas is collected and the solvent content in the gas is measured using gas chromatography (HP6890 manufactured by Hewlett Packard). The column used is 1.0 micron DB-FFAP (0.539 inmcp x 30 m), the carrier gas is He and the flow rate is 5.0 ml / min.
    Voltage / elongation test
    Each of the acrylic-based pressure-sensitive compositions of Examples 1-5 and Comparative Examples 1-7 were coated on a non-stick paper sheet (NS-50 manufactured by Lintec Corporation) using a cooker applicator, and dried and crosslinked. cured at a coating speed of 15 m / min to form a pressure-sensitive adhesive layer (50 μm thick). The sheet is cut into pieces measuring 5 mm x 60 mm, and 10 sheets of them are laminated to prepare a test sample. An AGl-kNG autograph (manufactured by Shimadzu Corporation) is used as a voltage tester. The test sample is pulled at a pulling speed of 100 mm with a distance between the 30 mm jaws to perform a tension / elongation test. The tension is measured at 300% stretching.
    EXAMPLE 1 (Preparation of acrylic-based polymer solution) 65 parts by weight of n-butyl acrylate (BA), 35 parts by weight of 2-ethylhexyl acrylate (2-EHA), 3 parts by weight of acrylic acid (AA), 0.05 part by weight of 4-hydroxybutyl acrylate (4-HBA) and 0.08 part by weight of AIBN (azobis-isobutylonitrile) as a polymerization initiator are added in a solvent toluene. Then, solution polymerization is carried out at 63 ° C for 8 hours to give an acrylic-based polymer solution. The weight average molecular weight of the acrylic-based polymer is 440,000. The acrylic acid content is 2.9% by weight based on all of the monomer components.
    (Preparation of acrylic pressure-sensitive adhesive composition) 30 parts by weight of a polymerized rosin ester (Rikatack PC J manufactured by Rika Fine Tech Co., softening point: 128 ° C, acid number 12 mg KOH / g) and 2 parts by weight of isocyanate crosslinking agent (Colonate L manufactured by Nippon Polyurethane Co., Ltd.) are added to the acrylic-based polymer solution prepared to provide a pressure-sensitive composition. acrylic based. EXAMPLE 2 (Preparation of acrylic-based polymer solution) 65 parts by weight of n-butyl acrylate, 35 parts by weight of 2-ethylhexyl acrylate, 3 parts by weight of acrylic acid, 0.05 parts by weight of 4-hydroxybutyl acrylate and 0.08 part by weight of AIBN as polymerization initiator are added in a mixed solvent of toluene / hexane = 70/30 (weight ratio). Then solution polymerization is carried out at 65 ° C for 8 hours to give an acrylic-based polymer solution. The weight average molecular weight of the acrylate polymer is 440,000. The acrylic acid content is 2.9% by weight based on all the monomer components.
    (Preparation of acrylic based adhesive composition)
    An acrylic-based pressure-sensitive composition is prepared in the same manner as in Example 1, except for the use of the aforementioned acrylic-based polymer solution.
    EXAMPLE 3 (Preparation of acrylic-based polymer solution) 100 parts by weight of n-butyl acrylate, 1 part by weight of acrylic acid, 0.1 part by weight of 2-hydroxyethyl acrylate (2- HEA) and 0.06 parts by weight of BPO (benzoyl peroxide) in the form of a polymerization initiator are added in a mixed solvent of toluene / hexane = 90/10 (weight ratio). Then, solution polymerization is carried out at 73 ° C for 8 hours to give an acrylic-based polymer solution. The weight average molecular weight of the acrylate polymer is 470,000. The acrylic acid content is 1.0% by weight based on all the monomer components. (Preparation of acrylic pressure-sensitive adhesive composition) 30 parts by weight of a polymerized rosin ester (DP291A manufactured by Rika Fine Tech Co., softening point: 105 ° C, acid number: 14 mg of KOH / g) and 2 parts by weight of isocyanate crosslinking agent (Colonate L manufactured by Nippon Polyurethane Co., Ltd.) are added to the acrylic-based polymer solution prepared to give a pressure sensitive composition based on acrylic. EXAMPLE 4 (Preparation of acrylic-based polymer solution) 70 parts by weight of n-butyl acrylate, 30 parts by weight of 2-ethylhexyl acrylate, 2.5 parts by weight of acrylic acid, 0, 5 parts by weight of 4-hydroxybutyl acrylate and 0.06 parts by weight of AIBN as polymerization initiator are added in a toluene solvent. Then, the solution polymerization is carried out at 65 ° C for 8 hours to give an acrylic-based polymer solution. The weight average molecular weight of the acrylic-based polymer is 380,000. The acrylic acid content is 2.4% by weight based on all the monomer components.
    (Preparation of acrylic pressure-sensitive adhesive composition)
    An acrylic-based pressure-sensitive composition is prepared in the same manner as in Example 1, except for the use of the aforementioned acrylic-based polymer solution.
    EXAMPLE 5 (Preparation of Acrylic-Based Polymer Solution) 35 parts by weight of n-butyl acrylate, 65 parts by weight of 2-ethylhexyl acrylate, 5 parts by weight of acrylic acid, 0.05 parts by weight of 4-hydroxybutyl acrylate and 0.06 part by weight of AIBN as polymerization initiator are added in a hexane solvent. Then, solution polymerization is performed at 70 ° C for 8 hours to give an acrylic-based polymer solution. The weight average molecular weight of the acrylate polymer is 390,000. The acrylic acid content is 4.7% by weight based on all the monomer components.
    (Preparation of acrylic pressure-sensitive adhesive composition)
    An acrylic-based pressure-sensitive adhesive composition is prepared in the same manner as in Example 1, except for the use of the above-mentioned acrylic-based polymer solution.
    COMPARATIVE EXAMPLE 1 (Preparation of Acrylic-Based Polymer Solution) 65 parts by weight of n-butyl acrylate, 35 parts by weight of 2-ethylhexyl acrylate, 2 parts by weight of acrylic acid, 0.05 1 part by weight of 4-hydroxybutyl acrylate and 0.08 part by weight of AIBN as polymerization initiator are added in a toluene solvent. Then, solution polymerization is carried out at 63 ° C for 8 hours to give an acrylic-based polymer solution. The weight average molecular weight of the acrylate polymer is 550,000. The acrylic acid content is 2.0% by weight based on all the monomer components.
    (Preparation of acrylic pressure-sensitive adhesive composition)
    An acrylic-based pressure-sensitive adhesive composition is prepared in the same manner as in Example 1, except for the use of the above-mentioned acrylic-based polymer solution.
    COMPARATIVE EXAMPLE 2
    (Preparation of an acrylic-based polymer solution) 65 parts by weight of n-butyl acrylate, 35 parts by weight of 2-ethylhexyl acrylate, 2 parts by weight of acrylic acid, 0.05 parts by weight of 4-hydroxybutyl acrylate and 0.08 parts by weight of AIBN as polymerization initiator are added in a toluene solvent. Then, solution polymerization is carried out at 83 ° C for 8 hours to give an acrylic-based polymer solution. The weight average molecular weight of the acrylate polymer is 330,000. The acrylic acid content is 2.0% by weight based on all the monomer components.
    (Preparation of acrylic based adhesive composition)
    An acrylic-based pressure-sensitive composition is prepared in the same manner as in Example 1, except for the use of the aforementioned acrylic-based polymer solution.
    COMPARATIVE EXAMPLE 3 (Preparation of acrylic-based polymer solution) 65 parts by weight of n-butyl acrylate, 35 parts by weight of 2-ethylhexyl acrylate, 6 parts by weight of acrylic acid, 0.05 1 part by weight of 4-hydroxybutyl acrylate and 0.08 part by weight of AIBN as polymerization initiator are added in a toluene solvent. Then, solution polymerization is carried out at 63 ° C for 8 hours to give an acrylic-based polymer solution. The weight average molecular weight of the acrylate polymer is 460,000. The acrylic acid content is 5.6% by weight based on all the monomer components.
    (Preparation of acrylic based adhesive composition)
    An acrylic-based pressure-sensitive composition is prepared in the same manner as in Example 1, except for the use of the aforementioned acrylic-based polymer solution.
    COMPARATIVE EXAMPLE 4 (Preparation of Acrylic Based Adhesive Composition)
    An acrylic-based pressure-sensitive composition was prepared in the same manner as in Example 1, except for the use of 30 parts by weight of terpene resin (YS Resin TO-125 manufactured by Yasuhara Chemical Co., Ltd., softening point: 125 ° C., Acid number: 2 mg KOH / g) instead of 30 parts by weight of a polymerized rosin ester.
    COMPARATIVE EXAMPLE 5 (Preparation of Acrylic Based Adhesive Composition)
    An acrylic-based pressure-sensitive composition is prepared in the same manner as in Example 1, except for the use of 30 parts by weight of hydrocarbon resin (Quintone 1325 manufactured by Nippon Zeon Co., Ltd., softening point 125 ° C., Acid number: 0 mg KOH / g) instead of 30 parts by weight of a polymerized rosin ester. COMPARATIVE EXAMPLE 6 (Preparation of Acrylic Based Adhesive Composition)
    An acrylic-based pressure-sensitive composition was prepared in the same manner as in Example 1, except for the use of 30 parts by weight of a partially hydrogenated rosin ester (Rikatack SE10 manufactured by Rika Fine Tech Co. softening point: 80 ° C., acid number: 6 mg KOH / g) instead of 30 parts by weight of a polymerized rosin ester.
    COMPARATIVE EXAMPLE 7 (Preparation of acrylic pressure-sensitive adhesive composition)
    An acrylic-based pressure-sensitive composition is prepared in the same manner as in Example 1, except for the use of 30 parts by weight of a polymerized rosin ester (Pencel KK manufactured by Arakawa Kagaku Co., softening: 160 ° C and above, acid number: 18 mg KOH / g) instead of 30 parts by weight of a polymerized rosin ester.
    (Preparation of acrylic adhesive tape)
    The temperature in a drying box is adjusted to 70, 80, 90 and 100 ° C. Each of the acrylic-based pressure-sensitive compositions of Examples 1-5 and Comparative Examples 1-7 were coated on a non-stick paper sheet (NS-50 manufactured by Lintec Corporation) using a cooker applicator, and dried and crosslinked. cured at a coating speed of 15 m / min to form a pressure-sensitive adhesive layer (thickness 80 μm). Then, the pressure-sensitive adhesive layer on the release paper is transferred onto a nonwoven fabric (MR14 base paper manufactured by Miki Tokushu Paper Mfg. Co., Ltd.) to prepare an acrylic-based pressure-sensitive tape ( total thickness: 160 μm), respectively.
    Table I

    It is clear from Table I that the acrylic-based pressure-sensitive compositions of Examples 1 to 5 meet all the characteristics of solvent economy, low viscosity and excellent adhesion, while pressure-sensitive compositions. Acrylic-based Comparative Examples 1-7 are lower than some of the solvent economy, low viscosity, and adhesion properties.
    权利要求:
    Claims (6)
    [1]
    A pressure sensitive adhesive composition based on (meth) acrylic, comprising a (meth) acrylic based copolymer, a hydrocarbon solvent and an adhesive, wherein the (meth) acrylic based copolymer has a weight average molecular weight of 350,000 to 4,90,000 and also contains, as monomeric components, an alkyl (meth) acrylate with an alkyl group having 2 to 18 carbon atoms and a vinyl compound having at least one acid group and the vinyl compound content is is in a range of 0.5 to 5% by weight based on all the monomer components, and the adhesive is a rosin derivative having a softening point of 90 to 150 ° C and an acid number of 8. at 16 mg KOH / g.
    [2]
    The pressure-sensitive adhesive composition based on (meth) acrylic according to claim 1, wherein the solids content is in a range of 36 to 60% by weight and the viscosity is in a range of 30 Pa. or less at 30 ° C.
    [3]
    A pressure-sensitive adhesive tape based on (meth) acrylic, comprising a carrier and a pressure sensitive adhesive layer formed by coating the (meth) acrylic pressure-sensitive adhesive composition according to claim 1 or 2 on the support.
    [4]
    The pressure-sensitive adhesive tape based on (meth) acrylic according to claim 3, wherein the haze value of the pressure-sensitive adhesive layer is 5 or less to 50 μm thick.
    [5]
    The (meth) acrylic pressure-sensitive adhesive tape of claim 3 or 4, wherein the tension of the pressure-sensitive adhesive layer is 5 N / cm 2 or less when the layer is stretched 300% in a tension / elongation test.
    [6]
    The (meth) acrylic pressure-sensitive adhesive tape according to any one of claims 3 to 5, wherein the amount of solvent remaining in the pressure-sensitive adhesive layer is 3000 ppm or less in a test. residual solvent.
    类似技术:
    公开号 | 公开日 | 专利标题
    JP4154512B2|2008-09-24|Tackifying acrylic adhesive
    TWI485213B|2015-05-21|Ultraviolet curing adhesive composition
    JP6685308B2|2020-04-22|Aqueous pressure sensitive adhesive composition
    JP5190668B2|2013-04-24|Tackifier, sticky / adhesive composition and sticky / adhesive film label
    JP6262410B1|2018-01-17|Aqueous pressure sensitive adhesive composition
    TWI646169B|2019-01-01|Thermosensitivity adhesive agent, thermosensitivity adhesive sheet, and thermosensitivity adhesive tape
    TWI462972B|2014-12-01|Adhesive, Adhesive / Adhesive Composition, Acrylic Adhesive / Adhesive Composition and Acrylic Active Energy Radiation Hardening Adhesive / Adhesive Composition
    JP5639446B2|2014-12-10|Easy peelable adhesive sheet and easy peelable adhesive tape
    WO2012133273A1|2012-10-04|Emulsion adhesive composition and re-peelable adhesive sheet
    JP2018520215A|2018-07-26|UV curable adhesives based on acrylic polymers
    JP5334374B2|2013-11-06|Self-wearing adhesive and self-wearing adhesive tape using the same
    US20180051197A1|2018-02-22|Pressure sensitive adhesives
    JP6258565B1|2018-01-10|Aqueous pressure sensitive adhesive composition
    JP3932328B2|2007-06-20|Method for producing acrylic pressure-sensitive adhesive sheet for optical members
    BE1017975A3|2010-02-02| ACRYLIC PRESSURE - SENSITIVE ADHESIVE COMPOSITION AND | ACRYLIC - BASED PRESSURE - SENSITIVE ADHESIVE STRIP.
    BE1009970A3|1997-11-04|Pressure sensitive adhesives and movies using such adhesive stickers.
    JP2009084421A|2009-04-23|Tackifier, tackifier for medical plaster, self-adhesive or self-adhesive composition, and self-adhesive for medical plaster
    JP6546910B2|2019-07-17|Temperature sensitive adhesive
    JP6931997B2|2021-09-08|UV curable acrylic copolymer
    JP4267329B2|2009-05-27|Polymer solution for | acrylic adhesive and method for producing the same, | acrylic adhesive, and | acrylic adhesive tape
    TWI589658B|2017-07-01|Thermal sensitive adhesive composition
    JP2005503450A|2005-02-03|Transparent pressure sensitive adhesive layer
    JP2009535439A|2009-10-01|Pressure sensitive adhesive containing n-butyl acrylate and hydroxybutyl | acrylate
    CN108026224B|2021-09-28|Adhesive resin modified adhesive material
    JP2006008827A|2006-01-12|Aqueous dispersion of composite resin composition for adhesive and adhesive composition
    同族专利:
    公开号 | 公开日
    JP2008189756A|2008-08-21|
    JP4325951B2|2009-09-02|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    EP1260566A2|2001-05-22|2002-11-27|Novacel|Protective adhesive films|
    JP6426887B2|2013-09-20|2018-11-21|積水化学工業株式会社|Acrylic adhesive for portable electronic devices and double-sided adhesive tape for portable electronic devices|
    JP6571667B2|2014-08-29|2019-09-04|スリーエム イノベイティブ プロパティズ カンパニー|Pressure sensitive adhesive composition, marking film and retroreflective sheet|
    法律状态:
    2012-07-31| RE| Patent lapsed|Effective date: 20120131 |
    优先权:
    申请号 | 申请日 | 专利标题
    JP2007024239|2007-02-02|
    JP2007024239A|JP4325951B2|2007-02-02|2007-02-02| acrylic pressure-sensitive adhesive composition andacrylic pressure-sensitive adhesive tape|
    [返回顶部]