• 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 relates to a method for making at least one layer of a film, wherein the method comprises the steps of: providing a first suspension comprising microfibrillated cellulose, providing a second suspension comprising dialdehyde microfibrillated cellulose, mixing the first suspension with the second suspension to form a mixture, applying said mixture to a substrate to form a fibrous web and drying said web to form at least one layer of said film. the present invention also relates to a film comprising said at least one layer.
    公开号:BR112019021081A2
    申请号:R112019021081-4
    申请日:2018-04-11
    公开日:2020-05-12
    发明作者:Land Hensdal Cecilia；Svensson Adrianna；Bergqvist Liv；TRAN CARLSTRÖM Amy；Axrup Lars
    申请人:Stora Enso Oyj；
    IPC主号:
    专利说明:

    BARRIER FILM UNDERSTANDING MICROFIBRILLATED CELLULOSE, DIALDEHYDE MICROFIBRILLATED CELLULOSE AND METHOD FOR MANUFACTURING BARRIER FILM
    Technical Field
    [0001] The present invention relates to a barrier film with a good and stable oxygen transmission rate (OTR) at high relative humidity (RH). More particularly, the present invention relates to a method of making such a film and a film produced.
    Background
    [0002] Today, films comprising microfibrillated cellulose (MFC) have proven to provide excellent barrier properties (see, for example, Aulin et al., Oxygen and oil barrier properties of microfibrillated cellulose films and coatings, Cellulose (2010) 17: 559- 574, Lavoine et al., Microfibrillated cellulose - Its barrier properties and applications in cellulosic materials: A review, Carbohydrate polymers 90 (2012) 735-764, Kumar et al., Comparison of nano- and microfibrillated cellulose films, Cellulose (2014) 21: 34433456), while the gas barrier properties are highly dependent on the humidity or relative humidity of the environment. Therefore, it is quite common for MFC films to need to be coated with a polymer film to prevent moisture or water vapor from swelling and disrupting the MFC film.
    [0003] The lack of gas barrier properties, such as oxygen or air with high relative humidity has been investigated and described, but most solutions
    Petition 870190100462, of 10/07/2019, p. 7/42
    2/24 suggested are expensive and difficult to implement on an industrial scale. One route would be to modify the MFC or nanocellulose, as disclosed in EP2554589A1 in which the MFC dispersion was modified with silane coupling agent. EP2551104A1 teaches the use of MFC and polyvinyl alcohol (PVOH) and / or polyuronic acid with enhanced barrier properties at the highest relative humidity (RH). Another solution is to coat the film with a film with high water resistance and / or low water vapor transmission rate. JP2000303386A discloses, for example, MFC film-coated latex, while US2012094047A teaches the use of wood hydrolysates mixed with polysaccharides such as MFC that can be coated with a polyolefin layer. In addition to this chemical modification, the possibility of crosslinking of fibrils or fibrils and copolymers was investigated. This improves the water stability of the films, but also the water vapor transmission rates. EP2371892A1, EP2371893A1, claim crosslinking MFC with metal ions, glyoxal, glutaraldehyde and / or citric acid, respectively.
    [0004] Another way to decrease sensitivity to cellulose is the chemical modification of cellulose with sodium periodate to obtain cellulose dialdehyde (DAC). Fibrillation of cellulose dialdehyde can produce a barrier film with better resistance to moisture. However, a dispersion comprising microfibrillated cellulose dialdehyde (DA-MFC) is very unstable since it sediments the DA-MFC and is spontaneously crosslinked to some extent already in the dispersion, leading to the fact that the
    Petition 870190100462, of 10/07/2019, p. 8/42
    3/24 microfibrils are attached or entangled. In addition, the low stability of the dispersion results in variations in the
    concentration of DA-MFC in the film, leading to a bad film formation and therefore, to properties in weak barriers. [0005] There is, therefore, the necessity in
    find a simple film production solution with good barrier properties, even in high humidity.
    summary
    [0006] It is an object of the present invention to provide an improved film comprising microfibrillated cellulose, which has improved barrier properties, even with higher relative humidity in the surroundings.
    [0007] It is an object of the present invention to provide an improved film comprising microfibrillated cellulose which is capable of providing good barrier properties, even if moisture fluctuates.
    [0008] The invention is defined by the attached independent claims. The embodiments are set out in the attached dependent claims and in the description and drawings that follow.
    [0009] The present invention relates to a method for making at least one layer of a film in which the method comprises the steps of: providing a first suspension comprising a microfibrillated cellulose, providing a second suspension comprising microfibrillated cellulose dialdehyde, mixing the first suspension with the second suspension to form a mixture, apply said mixture to a substrate to form a weft
    Petition 870190100462, of 10/07/2019, p. 9/42
    4/24 fibrous and drying said web to form at least one layer of said film. It has surprisingly been found that it is possible to produce a very stable suspension or mixture by mixing a first suspension comprising microfibrillated cellulose and a second suspension comprising dialdehyde microfibrillated cellulose. It is crucial that a suspension used for the production of barrier materials is stable, as the uneven distribution of fibrils will lead to deteriorated barrier properties. In addition, it has been found that the use of microfibrillated cellulose from the first suspension and microfibrillated cellulose from the second suspension (DA-MFC) enables the production of at least one layer of film that gives the film enhanced barrier properties in high humidity, especially in floating humidity.
    [0010] The mixture preferably comprises between 20-95% by weight of microfibrillated cellulose dialdehyde based on the total fiber weight of the mixture. The mixture preferably comprises between 5-80% by weight of microfibrillated cellulose based on the total fiber weight of the mixture. Depending on the end use and the properties of the microfibrillated cellulose in the first suspension and the second suspension, the amount of microfibrillated cellulose dialdehyde may vary. The dry content of the mixture applied to the substrate is preferably between 1-10% by weight. Depending on the substrate on which the mixture is applied, the dry content of the mixture can vary.
    [0011] At least one layer of the film preferably has an oxygen transmission rate in the range of 0.1 to 300 cm 3 / m 2 / 24h, according to the ASTM standard
    Petition 870190100462, of 10/07/2019, p. 10/42
    5/24
    D-3985, 50% relative humidity at 23 ° C and / or 90% relative humidity at 38 ° C. According to the present invention, it is possible to produce at least one layer of a film that has very good oxygen barrier properties at high humidity. It was especially found that the film according to the present invention is more resistant to moisture fluctuations, that is, the film still has good barrier properties, even if the humidity varies.
    [0012] The substrate is preferably a polymer or metallic substrate. It is preferred that the mixture is coated by molding on said substrate.
    [0013] The method can also comprise the step of pressing the film after drying. The barrier properties of the film have been shown to increase if the film is subjected to an increase in pressure after drying. The pressure applied in the pressing is preferably greater than 40kN / m (overpressure), more preferably between 100-900 kN / m. The temperature is preferably raised to between 50-200 ° C, preferably between 100-150 ° C during the pressing of the film.
    [0014] The mixture may also comprise additives, preferably any of starch, carboxymethylcellulose, a filler, retention chemicals, flocculation additives, deflocculation additives, dry strength additives, softeners or mixtures thereof. It may be possible to add additives that improve the different properties of the mixture and / or the film produced, such as latex and / or polyvinyl alcohol, to
    Petition 870190100462, of 10/07/2019, p. 11/42
    6/24 increase the ductility of the film. It may be possible to add the additive to the first suspension, the second suspension and / or the mixture.
    [0015] According to one aspect of the invention, the dialdehyde cellulose microfibrillin in the second suspension has an oxidation degree between 25-75%.
    [0016] The present invention further relates to a film comprising microfibrillated cellulose, wherein the film has an oxygen transmission rate in the range of 0.1 to 300 cm 3 / m 2/24 measured according to ASTM D3985 , at a relative humidity of 50% at 23 ° C and / or at a relative humidity of 90% at 38 ° C, and in which at least one layer of the film comprises a mixture of microfibrillated cellulose and microfibrillated cellulose dialdehyde.
    [0017] A film preferably has a Weight base less than 50 g / m 2 , preferably between 10-50 g / m 2 .[0018] A film is preferably an
    multilayer film comprising more than one layer. According to one aspect of the invention, at least one layer of the multilayer film comprises latex to increase the ductility of the film.
    [0019] According to one aspect of the invention, at least one layer of the multilayer film is a water vapor barrier film comprising any of polyethylene (PE), polypropylene (PP), polyamide, polyethylene terephthalate (PET ) or ethylene vinyl alcohol (EVOH). The water vapor barrier film preferably has a weight between 10-60 g / m 2 , preferably 30-50 g / m 2 . A layer of polyethylene
    Petition 870190100462, of 10/07/2019, p. 12/42
    7/24 (PE) on at least one side of the film, which comprises microfibrillated cellulose dialdehyde, also improves the elasticity of the film and provides heat sealing properties.
    [0020] According to another aspect of the invention, at least one layer of the multilayer film is a metallized barrier layer. The phrase metallized barrier layer means a thin layer of metal that provides barrier properties that reduce permeability, for example, to oxygen, water, water vapor and light. According to one aspect of the invention, said metallized barrier layer is a layer of metal or metal oxide deposited in physical vapor, or a layer of metal or metal oxide deposited in chemical vapor, wherein said metal or oxide of metal is selected from the group consisting of aluminum, aluminum oxides, magnesium oxides, silicon oxides, copper, magnesium and silicon. Preferably, the metallized barrier layer weighs between 50-250 mg / m 2 , preferably between 75-150 mg / m 2 . The present invention further relates to a packaging material comprising a laminated base material with at least one layer of the film described above comprising a mixture of a microfibrillated cellulose and microfibrillated cellulose dialdehyde. Said base material is preferably paper or cardboard. According to one aspect of the invention, the paper or cardboard of said packaging material has a weight between 20-500 g / m 2 , for example between 80-400 g / m 2 . The packaging material may comprise a multilayer film which, in addition to the film comprising a mixture of a microfibrillated cellulose and a
    Petition 870190100462, of 10/07/2019, p. 13/42
    8/24 microfibrillated cellulose dialdehyde, also comprises one or more of a water vapor barrier layer and / or a metallized barrier layer described above.
    Description of Modalities
    [0021] The method according to the present invention relates to providing a first suspension comprising microfibrillated cellulose and mixing said first suspension with a second suspension comprising microfibrillated cellulose dialdehyde (DA-MFC) to form a mixture. The mixture is then applied on a substrate to form a fibrous web and said web is subsequently dried to form at least one layer of the film. It has surprisingly been found that by forming a mixture comprising microfibrillated cellulose and microfibrillated cellulose from cellulose dialdehyde (DAMFC), a more stable mixture is achieved. This improves the handling and the ability of the mixture to form good barrier films. Furthermore, it has been found that, using said mixture in the production of at least one layer of a film, a film with improved high moisture barrier properties can be produced. Above all, it was surprisingly found that the film has a very good resistance against floating moisture. The barrier properties of the film were still good, even though the humidity fluctuated from low to high, low and back to high.
    [0022] The at least one layer of the film is produced by applying said mixture to a substrate to form a fibrous web and drying said web to form at least one layer of said film. THE
    Petition 870190100462, of 10/07/2019, p. 14/42
    9/24 drying of said web can be done in any conventional manner. The dry content of at least one layer of the film after drying is preferably above 95% by weight.
    [0023] The method may also comprise the stage of pressing the film after drying. The barrier properties of the film have been shown to increase if the film is subjected to an increase in pressure after drying. The pressure used is preferably between 40-900kPa and the pressing can take a period of less than 10 minutes, preferably between 1 second and 10 minutes. It is preferable that the pressing is carried out at elevated temperatures. The temperatures used during pressing can be between 50-200 ° C, preferably between 100-150 ° C. Pressing can be done on any conventional equipment, such as presses or calenders. By combining the use of pressing, preferably hot pressing of the formed film, the film barrier is greatly increased.
    [0024] The substrate can be a polymer or metallic substrate to which the mixture is melted. The gypsum-coated fibrous band can be dried in any conventional manner and later optionally removed from the substrate. It may be possible to mold or coat more than one layer on the substrate, forming a multilayer film. It is possible to produce a film comprising more than one layer, wherein at least one of the layers comprises the mixture according to the invention. It may also be possible that more than one layer of the film comprises the mixture according to the invention. It may also be possible that one or more layers of the film comprise only cellulose
    Petition 870190100462, of 10/07/2019, p. 15/42
    10/24 microfibrillated from the first suspension, i.e., not comprising microfibrillated cellulose dialdehyde (DA-MFC). It may also be possible for one or more layers of the film to be a water vapor barrier film comprising any of polyethylene (PE), polypropylene (PP), polyamide, polyethylene terephthalate (PET) or ethylene vinyl alcohol (EVOH). It may also be possible for one or more layers of the film to be a metallized barrier layer, comprising any one of aluminum, aluminum oxides, magnesium oxides, silicon oxides, copper, magnesium and silicon. The film may comprise two, three, four, five, six, seven, eight, nine, ten or more layers.
    [0025] The substrate can also be a porous thread from a paper-making machine, that is, any type of paper-making machine known to someone skilled in the art used to make paper, cardboard, fabric or any similar products.
    [0026] The substrate can also be a base material, such as paper or cardboard product, to which the mixture is applied to form a coated product suitable for use as a packaging material. Such a coated product can be used as a liquid packaging card suitable for containers and packages with a liquid content. A packaging material including a layer of the mixture according to the invention may comprise other barrier layers to prevent the migration of air, water and aromas through the base material. According to one aspect, a packaging material may include at least one water vapor barrier layer comprising any one of
    Petition 870190100462, of 10/07/2019, p. 16/42
    11/24 polyethylene (PE), polypropylene (PP), polyamide, polyethylene terephthalate (PET) or ethylene vinyl alcohol (EVOH). The packaging material may also include one or more metallized barrier layer (s) comprising any one of aluminum, aluminum oxide, magnesium oxide or silicon oxide. The microfibrillated cellulose in the first suspension is microfibrillated cellulose produced from mechanical, thermomechanical or chemical pulp.
    [0027] The microfibrillated cellulose of the first suspension is preferably produced from kraft pulp. The microfibrillated cellulose in the first suspension preferably has a Schopper Riegler (SR °) value greater than 90. According to another modality, MEC may have a Schopper Riegler (SR °) value greater than 93. According to yet another modality , the MEC can have a Schopper Riegler (SR °) value greater than 95. The Schopper-Riegler value can be obtained using the standard method defined in EN ISO 5267-1. This high SR value is determined for a pulp, with or without additional chemicals, so the fibers have not consolidated into a film or started, for example, hornification. The dry solids content of this type of weft, before disintegrating and measuring the SR, is less than 50% (w / w). To determine the Schopper Riegler value, it is preferable to collect a sample just after the section of the yarn, where the consistency of the wet mat is relatively low. The expert understands that chemicals for papermaking, such as retention agents or water removal agents, have an impact on the RS value. The SR value specified in this document should be understood as an indication, but not a limitation, for
    Petition 870190100462, of 10/07/2019, p. 17/42
    12/24 reflect the characteristics of the MFC material itself.
    [0028] The microfibrillated cellulose dialdehyde in the second suspension must, in this context, mean a cellulose dialdehyde treated in such a way as to be microfibrillated. The production of the microfibrillated cellulose dialdehyde is done by treating the cellulose dialdehyde, for example, by a homogenizer or in any other way, so that fibrillation occurs to produce microfibrillated cellulose dialdehyde. The microfibrillated cellulose dialdehyde in the second suspension preferably has a degree of oxidation between 25-75%, preferably between 30-65%, even more preferably between 30-50% or more preferably between 3545%. The degree of oxidation was determined according to the following description: after the cellulose dialdehyde reaction, the amount of C2-C3 bonds in the cellulose that are converted to dialdehydes is measured. The degree of oxidation is the number of C2-C3 bonds that are converted compared to all C2-C3 bonds. This is measured with a method by H. Zhao and N.D. Heindel, Determination of Degree of Substitution of Formyl Groups in Polyaldehyde Dexran by the Hydroxylamine Hydrochloride Method, Pharmaceutical Research, vol. 8, pp. 400-402, 1991 where the available aldehyde groups react with hydroxylamine hydrochloride. This forms oxime groups and releases hydrochloric acid. Hydrochloric acid is titrated with sodium hydroxide until pH 4 is reached and the degree of oxidation is subsequently calculated according to the formula below. The content of aldehyde received is divided by two to obtain the value of the degree of oxidation, since an oxidized anhydroglycosis unit has two groups of aldehyde.
    Petition 870190100462, of 10/07/2019, p. 18/42
    13/24
    - X 100
    V Na oH = quantity in hydroxide of sodium needed to reach pH 4 (I) Coaon = 0.1 mol / L kamostra = PSSO SeCO gives DAC sample analyzed (g) M w = 160 g / mol, what is the weight molecular of the unit
    cellulose dialdehyde
    [0029] The mixture may also comprise additives, preferably any of starch, carboxymethylcellulose, a filler, retention chemicals, flocculation additives, deflocculation additives, dry strength additives, softeners or mixtures thereof. It may be possible to add additives that improve the different properties of the mixture and / or the film produced. It may be possible to add the additive to the first suspension, the second suspension and / or the mixture. It has been shown that the use of a softener, such as sorbitol, glycerol, polyethylene glycol, sorbic acid, propylene glycol, erythritol, maltitol or polyethylene oxides, will modify and improve some of the mechanical properties of the film, especially the stretch in the breaking properties. The amount of sorbitol used is preferably between 1-20% in dry weight of the film.
    [0030] According to one embodiment, the film comprising microfibrillated cellulose and microfibrillated cellulose dialdehyde has an oxygen transmission rate in the range of 0.1 to 300 cm 3 / m 2 / 24h measured according to the ASTM D-3985 standard, at a relative humidity of 50% at 23 ° C and / or at a relative humidity of 90% at 38 ° C.
    Petition 870190100462, of 10/07/2019, p. 19/42
    14/24
    [0031] The amount of microfibrillated cellulose in the film produced is preferably between 5-80% by weight of the total dry weight of the film, preferably between 10-60% by weight of the total dry weight of the film and even more preferably between 10-40% by weight of the total dry weight of the film. The amount of microfibrillated cellulose dialdehyde in the film produced is preferably between 20-95% by weight of the total dry weight of the film, preferably between 40-90% by weight of the total dry weight of the film and even more preferably between 60-90% by weight of the total dry weight of the film.
    [0032] According to one embodiment, the film may have a base weight of less than 50 g / m 2 , or less than 35 g / m 2 , or less than 25 g / m 2 . The base weight is preferably at least 10 g / m 2 , preferably between 10-50 g / m 2 , even more preferred between 10-35 g / m 2 and most preferred between 10-25 g / m 2 .
    [0033] Microfibrilated cellulose (MFC) means, in the context of the patent application, a cellulose particle fiber on a nanometric scale or fibril with at least one dimension less than 100 nm. MFC comprises cellulose fibers or lignocellulose partially or totally fibrillated. The released fibrils have a diameter of less than 100 nm, while the actual diameter of the fibril or the particle size and / or proportion distribution (length / width) depends on the source and the manufacturing methods. The smallest fibril is called elemental fibril and has a diameter of approximately 2-4 nm (see, for example ChingaCarrasco, G., Cellulose fibers, nanofibrils and microfibrils: The morphological sequence of MFC components
    Petition 870190100462, of 10/07/2019, p. 20/42
    15/24 from a plant physiology and fiber technology point of view, Nanoscale research letters 2011, 6: 417), although it is common for the aggregated form of elementary fibrils, also defined as microfibril {Fengel, D., Ultrastructural behavior of cell wall polysaccharides, Tappi J., March 1970, Vol. 53, number 3.), be the main product obtained when MFC is manufactured, for example, using an extended refining process or disintegration process due to pressure drop. Depending on the source and the manufacturing process, the length of the fibrils can vary from about 1 to more than 10 micrometers. A gross MFC classification can contain a substantial fraction of fibrillated fibers, that is, protruding fibrils from the tracheid (cellulose fiber) and with a certain amount of fibrils released from the tracheid (cellulose fiber).
    [0034] There are different acronyms for MFC, such as cellulose microfibrils, fibrillated cellulose, nanofibrillated cellulose, fibril aggregates, nanoscale cellulose fibrils, cellulose nanofibers, cellulose nanofibrils, cellulose microfibers, cellulose fibrils, microfibrillary cellulose, microfibril aggregates and cellulose microfibril aggregates. MFC can also be characterized by several physical or physical-chemical properties, such as a large surface area or its ability to form a gel-like material with a low solids content (1-5% by weight) when dispersed in water. The cellulose fiber is preferably fibrillated to the point that the final specific surface area of the MFC formed is about 1 to about 200 m 2 / g, or more preferably 50-200 m 2 / g
    Petition 870190100462, of 10/07/2019, p. 21/42
    16/24
    when determined for a material lyophilized with the BET method • [0035] There are several methods to product MEC, such as refining in passage only or multiple, pre- hydrolysis then per refining or disintegration of high
    shear or release of fibrils. Generally, one or more pre-treatment steps may be required to make MFC manufacturing energy efficient and sustainable. The cellulose fibers of the pulp to be supplied can thus be pre-treated enzymatically or chemically, for example, to hydrolyze or dilate the fibers or to reduce the amount of hemicellulose or lignin. Cellulose fibers can be chemically modified before fibrillation, where cellulose molecules contain different functional groups (or more) than those found in the original cellulose. These groups include, among others, carboxymethyl (CMC), aldehyde and / or carboxyl groups (cellulose obtained by oxidation mediated by Noxila, for example TEMPO) or quaternary ammonium (cationic cellulose). After being modified or oxidized in one of the methods described above, it is easier to disintegrate the fibers in the MEC or nanofibrillar or NEC size.
    [0036] Nanofibrillar cellulose may contain some hemicelluloses; the amount depends on the source of the plant. Mechanical disintegration of pretreated fibers, for example, the raw material of hydrolyzed, pre-dilated or oxidized cellulose is carried out with suitable equipment, such as refiner, grinder, homogenizer, collider, friction grinder, ultrasound sonicator, fluidizer, such as microfluidizer , macrofluidizer or homogenizer of the
    Petition 870190100462, of 10/07/2019, p. 22/42
    17/24 fluidizer type. Depending on the MFC's manufacturing method, the product may also contain fines or nanocrystalline cellulose or, for example, other chemicals present in wood fibers or in the paper-making process. The product may also contain various amounts of micron size fiber particles that have not been efficiently fibrillated. MFC is produced from wood cellulose fibers, both wood fiber and glass fiber. It can also be manufactured from microbial sources, agricultural fibers, such as wheat straw pulp, bamboo, bagasse or other sources of fibers other than wood. It is preferably obtained from pulp including virgin fiber pulp, for example, mechanical, chemical and / or thermomechanical pastes. It can also be made from torn or recycled paper.
    [0037] The definition of MFC described above includes, among others, the proposed new TAPPI W13021 standard on cellulose nanofibril (CNF) that defines a cellulose nanofiber material containing several elementary fibrils with crystalline and amorphous regions, with a high proportion with width of 5-30 nm and aspect ratio generally greater than 50.
    [0038] In an embodiment of the present invention, microfibrillated cellulose is fibrillated in the presence of the moisture resistance additive. This means that the moisture resistance additive is added before the fibrillation process or during the fibrillation process.
    Brief Description of the Figures
    [0039] Figure 1: describes the particle size distribution during storage for two
    Petition 870190100462, of 10/07/2019, p. 23/42
    18/24 suspensions;
    [0040] Figure 2: describes the OTR value for films with floating humidity;
    [0041] Figure 3: shows barrier properties in the form of OTR and WVTR, respectively, for independent films;
    [0042] Figure 4: shows barrier properties in the form of OTR and WVTR, respectively, for films coated with PE; and
    [0043] Figure 5: shows barrier properties in the form of OTR and WVTR, respectively, of LPB structures.
    Examples
    Example I: Stability Test
    [0044] The stability during storage of a suspension comprising microfibrillated cellulose dialdehyde (DA-MFC) was compared with a suspension comprising a mixture of microfibrillated cellulose and microfibrillated cellulose dialdehyde.
    [0045] The suspension comprising a mixture of MEC and DA-MFC comprises 40% by weight of the total dry weight of the MEC suspension and 60% by weight of the total dry weight of the DA-MFC suspension. The degree of oxidation of DA-MFC was 40%.
    [0046] Both suspensions were stored for 15 days. The particle size distribution of the suspensions before storage is seen as starting material, since the particle size distribution for both suspensions was the same. The particle size distribution was measured with Mastersizer 3000 (Malvern Instruments Ltd., United Kingdom).
    Petition 870190100462, of 10/07/2019, p. 24/42
    19/24
    [0047] The results can be seen in figure 1. It is evident in figure 1 that the suspension comprising a mixture of DA-MFC and MFC has a much more stable particle size distribution after storage, compared to the suspension comprising DA-MFC only.
    Example II: OTR values after moisture fluctuation
    [0048] The OTR value for films comprising only MFC, only DA-MFC and films comprising mixtures of MFC and DA-MFC was measured at 90% humidity at 38 ° C in two different cycles.
    [0049] Each film has a weight of about 40 g / m * 2 and the OTR value was measured according to the ASTM D-3985 standard. The degree of oxidation of the DA-MFC used was 38%. The films were stored at room temperature and then the OTR value was measured at a high humidity of 90% at 38 ° C and this represents the OTR value in the I cycle. Subsequently, the films were stored again at room temperature and the OTR value was measured again to a high humidity 90% at 38 ° C, and this is the OTR value in the second cycle.
    [0050] The results can be seen in the Figure
    2. Shown in Figure 2 that the OTR values for films comprising a mixture of DA-MFC and MFC have better OTR value (low value being good) in the 2nd cycle compared with the film comprising only DA- MFC and also for film comprising MFC only.
    Example III: Breakage Deformation for DA-MFC Films
    [0051] DA-MFC with an average D. O. of 30% was mixed with native MFC, with a mass ratio of
    80% / 20%. The solids content of the dispersion was 3% by weight.
    Petition 870190100462, of 10/07/2019, p. 25/42
    20/24
    The mixture was coated on a plastic substrate. After drying at room temperature, the film thickness was 58 pm. The film samples were laminated on PE film with a weight of 25 g / m 2 .
    [0052] The stress at break was measured by means of a standard tensile test (ISO 1924-2 with a span length of 20 mm), in which the film to be tested was stretched with a test speed of 2 mm / minute , to a point where it broke. The stress at break corresponds then to the percentage elongation when breaking, that is, to what extent in percentage the film deforms without breaking when subjected to elongation.
    [0053] The results are seen in Table 1 below and show that the application of a PE layer on a film comprising DA-MFC leads to better stress at break.
    Tested Material Breaking Stress (%) DA-MFC film 1.0 DA-MFC film + PE layer 1.2
    Table 1
    Example IV: Barrier Properties of DAMFC Films and Laminates
    [0054] DA-MFC with an average D. O. of 30% was mixed with the native MFC, with a mass ratio of 80% / 20%. The solids content of the dispersion was 3% by weight. The mixture was coated on a plastic substrate. After drying at room temperature, the film thickness was 58 pm. This film is known as DAPetition film 870190100462, from 10/07/2019, p. 26/42
    21/24
    MFC. Films with 100% native MFC were also obtained as a comparison, known as MFC film. Adhesion of the native MFC film to the substrate was very low for successful casting. To solve this problem, 15% by weight sorbitol was added to the films. The addition of sorbitol is seen with (s) in Table 2 and in the figures.
    [0055] The film samples were laminated on PE film with a weight of 25 g / m 2 and other film samples were laminated on a weight of 239 g / m 2 and in PE to form an LPB structure. This LPB structure was:
    [0056] (15 + plate + 15 + film + 50) where the numbers are the weight of the PE layers in g / m 2 . The results were compared to a commercial plate with a weight of 265 g / m 2 , with layers of PE on both sides. The weight of the PE layers was 14 g / m 2 on the upper side and 24 g / m 2 on the lower side.
    [0057] OTR was measured according to the ASTM F-1927 standard, in the following climates: 23 ° C, 50% RH; 23 ° C, 80% RH; and 38 ° C, 90% RH. WVTR was measured according to the ASTM F-1249 standard, in the following climates: 23 ° C, 50% RH; 23 ° C, 80% RH; and 38 ° C, 90% RH. For the two highest climates, the laminates were stored in the measurement climate for 2 weeks prior to measurement, to ensure that moisture balance was achieved in the sample during measurement. This was not necessary for films without PE.
    [0058] The results are shown in Table 2 and Figures 3-5. Here it can be seen that the DAMEC film has a lower OTR in high humidity (ie 80% and
    Petition 870190100462, of 10/07/2019, p. 27/42
    22/24
    90% RH, respectively) compared to the film
    Native MFC.
    OTR 23/50 OTR 23/80 OTR 38/90 WVTR 23/50 WVTR 23/80 WVTR 38/90 MFC film 1.3 43 112 9.8 351 > 2000 DA- filmMFC 2.4 3.6 82 67 214 900 MFC film(s) + PE 0.3 146 720 2.4 2.3 14 DA- filmMFC + PE 1.0 8.3 128 1.3 1.8 8.6 PE + board + PE > 1,000 > 1,000 - 1.9 7.2 23 LPB with MFC film(s) 0.8 69 447 1 1.4 9.5 LPB with DA- filmMFC 0.24 8.2 134 0.77 1.4 4.6
    Table 2: Film Barrier Properties and
    DA-MFC laminates (- = not measured).
    [0059] The results of Example IV show that the DA-MFC film had a better oxygen barrier than the native MFC film, especially at 23 ° C, 80% RH (Figure 1; Table 2). In addition, the DA-MFC film presented a slight barrier to water vapor, even at high relative humidity, where the native MFC failed to provide a barrier to water vapor. The WVTR of the native MFC film was above the range at 38 ° C, 90% relative humidity. In low relative humidity, the native MFC presented a better barrier to water vapor (Figure 3; Table 2).
    [0060] The insertion of the DA-MFC film instead of the native MFC film with sorbitol in a packaging material provided a better oxygen barrier function in high relative humidity (Figures 4-5). The level of
    Petition 870190100462, of 10/07/2019, p. 28/42
    23/24
    WVTR in the structure was largely controlled by the amount of PE in the structure, however the LPB with DA-MFC film was better than that with MEC film at 38 ° C, 90% RH (Table 2).
    [0061] Thus, it is possible to customize packaging materials, including DA-MFC films, according to the need for barrier properties.
    Example V: OTR of DA-MFC Metallized Films and Laminates
    [0062] DA-MFC with an O.D. medium of 30% was mixed with the native MEC, with a mass ratio of 80% / 20%. The solids content of the dispersion was 3% by weight. The mixture was coated on a plastic substrate. After drying at room temperature, the film thickness was 58 gm. This film is known as DAMFC film. Films were also made with 100% native MEC as a comparison, known as MEC film. The adhesion of the native MEC film to the substrate was very low
    for foundry successful. For solve this problem, sorbitol to 15% in weight was added at films. The addition of sorbitol is noted with S) at Table 3. [0063] The films were metallized with technology Physical Deposition of Steam, fulfilled in camera of vacuum. 0 aluminum was vaporized by the heat and.
    when it reached the film it condensed on top of it. The thickness of the Al layer was about 30-40 nm (100 mg / m 2 ).
    Petition 870190100462, of 10/07/2019, p. 29/42
    24/24
    OTR 23/80 OTR 38/90 Metallic MFC film (s) 74 316 Metallic DA-MFC film 6, 1 48 LPB with metallized MFC film (s) 13.5 343 LPB with metallized DA-MFC film 4.0 141
    Table 3
    [0064] As can be seen in Table 3, the metallized DA-MFC film proves to be a very efficient oxygen barrier compared to the 23/80 (ie 23 ° C and 80% RH) MFC film and 38 / 90. Also the laminate comprising LPB with metallized DA-MFC film has a significantly lower OTR compared to LPB with metallized MFC film.
    [0065] In view of the detailed description above of the present invention, other modifications and variations will be evident to those skilled in the art. However, it should be apparent that these other modifications and variations can be made without departing from the spirit and scope of the invention.
    权利要求:
    Claims (22)
    [1]
    1. Method for making at least one layer of a film, the method comprising the steps of:
    providing a first suspension comprising microfibrillated cellulose, providing a second suspension comprising microfibrillated cellulose dialdehyde, mixing the first suspension with the second suspension to form a mixture, applying said mixture to a substrate to form a fibrous web and drying said web to form at least one layer of said film.
    [2]
    A method according to claim 1, wherein the mixture comprises between 20-95% by weight of microfibrillated cellulose dialdehyde, based on the total fiber weight of the mixture.
    [3]
    Method according to any one of the preceding claims, wherein the blend comprises between 5-80% by weight of microfibrillated cellulose, based on the total fiber weight of the blend.
    [4]
    Method according to any one of the preceding claims, wherein the dry content of the mixture applied to the substrate is between 1 and 10% by weight.
    [5]
    5. Method according to any one of the preceding claims, wherein the at least one film layer has an oxygen transmission rate in the range of 0.1 to 300 cm 3 / m 2/24 h, according to standard ASTM D-3985, at a relative humidity of 50% at 23 ° C and / or at a relative humidity of 90% at 38 ° C.
    Petition 870190100462, of 10/07/2019, p. 31/42
    2/4
    [6]
    A method according to any one of the preceding claims, wherein the substrate is a polymer or metal substrate.
    [7]
    A method according to any one of the preceding claims, wherein said method further comprises the step of pressing the film after drying.
    [8]
    Method according to claim 7, wherein the temperature is increased to 100-150 ° C during the pressing of the film.
    [9]
    A method according to any one of the preceding claims, wherein said mixture further comprises any of starch, carboxymethylcellulose, a filler, retention chemicals, flocculation additives, deflocculation additives, dry strength additives, softeners or mixtures thereof.
    [10]
    A method according to any one of the preceding claims, wherein the microfibrillated cellulose dialdehyde in the second suspension has a degree of oxidation between 25-75%.
    [11]
    11. Film comprising microfibrous cellulose ibrilada, wherein the film has an oxygen transmission rate in the range of 0.1 to 300 cm 3 / m 2/24 h measured in accordance with ASTM D-3985 at a relative humidity 50% at 23 ° C and / or at a relative humidity of 90% at 38 ° C, and wherein at least one layer of the film comprises a mixture of microfibrillated cellulose and microfibrillated cellulose dialdehyde.
    [12]
    12. Film according to claim 11, in
    Petition 870190100462, of 10/07/2019, p. 32/42
    3/4 that the film has a base weight of less than 50 g / m 2 , preferably between 10-50 g / m 2 .
    [13]
    Film according to either of claims 11 or 12, wherein said film is a multilayer film comprising more than one layer.
    [14]
    Film according to any one of claims 1 to 13, wherein said film is a multilayer film and, wherein at least one layer of the film is a water vapor barrier film comprising any one of polyethylene (PE), polypropylene (PP), polyamide, polyethylene terephthalate (PET) or ethylene vinyl alcohol (EVOH).
    [15]
    15. Film according to claim 14, in
    that the film of water vapor barrier has an weight between 10 - 60 g / m 2 , preferably 30 - 50 g / m 2 . 16. Film, according to any an of claims 11 to 15, in which said film is an
    multilayer film and wherein at least one layer of the film is a metallized barrier layer.
    [16]
    A film according to claim 16, wherein said metallized barrier layer is a physical layer of metal or metal oxide deposited in vapor, or a layer of metal or metal oxide in chemical vapor deposition.
    [17]
    Film according to claim 17, wherein said metal or metal oxide is selected from the group consisting of aluminum, aluminum oxides, magnesium oxides, silicon oxides, copper, magnesium and silicon.
    [18]
    19. Film according to any of the
    Petition 870190100462, of 10/07/2019, p. 33/42
    4/4 claims 16 to 18, wherein said metallized barrier layer has a weight between 50 - 250 mg / m 2 , preferably 75 - 150 mg / m 2 .
    [19]
    Packaging material comprising a base material and at least one layer of the film as claimed in any of claims 11-19.
    [20]
    The packaging material according to claim 20, wherein the base material is paper or cardboard.
    [21]
    22. The packaging material according to claim 21, wherein the paper or cardboard has a weight between 20 - 500 g / m 2 .
    [22]
    23. The packaging material according to claim 21, wherein the paper or cardboard has a weight between 80 - 400 g / m 2 .
    类似技术:
    公开号 | 公开日 | 专利标题
    BR112019021081A2|2020-05-12|BARRIER FILM UNDERSTANDING MICROFIBRILLATED CELLULOSE, DIALDEHYDE MICROFIBRILLATED CELLULOSE AND METHOD FOR MANUFACTURING BARRIER FILM
    US10676868B2|2020-06-09|Method for producing a film having good barrier properties
    US10577747B2|2020-03-03|Method to produce a film comprising microfibrillated cellulose and an amphoteric polymer
    US20180245289A1|2018-08-30|Surface sizing of dense films
    US11105045B2|2021-08-31|Method for the production of a film comprising microfibrillated cellulose, a film and a paper or paperboard product
    JP2020502379A|2020-01-23|Method for producing coated paper, paperboard or film and coated paper, paperboard or film
    JP2021507830A|2021-02-25|Multilayer film containing microfibrillated cellulose
    BR112019023763A2|2020-05-26|A METHOD OF MANUFACTURING A FILM HAVING LOW OXYGEN TRANSMISSION RATE VALUES
    BR112019015418A2|2020-03-31|METHOD OF MANUFACTURING A FILM UNDERSTANDING MICROFIBRILLATED CELLULOSIS
    BR112021011407A2|2021-08-31|SURFACE-TREATED FIBROUS MATERIALS AND METHODS FOR THEIR PREPARATION
    BR112020007688A2|2020-10-13|a method for producing a film having good barrier properties and a film having good barrier properties
    JP2021517216A|2021-07-15|Methods for Producing Films with Good Barrier and Improved Fracture Strain
    BR112020020682A2|2021-01-19|METHOD FOR THE PRODUCTION OF A COATED PAPER, CARDBOARD OR FILM AND A COATED PAPER, CARDBOARD OR FILM
    WO2020044209A1|2020-03-05|Method for treating a nanocellulose film and a film treated according to the method
    WO2020058803A1|2020-03-26|A method for improving adhesion during production of film
    同族专利:
    公开号 | 公开日
    ZA201906442B|2020-08-26|
    US20200086604A1|2020-03-19|
    CN110506143A|2019-11-26|
    SE540870C2|2018-12-11|
    CA3058710A1|2018-10-08|
    WO2018189698A1|2018-10-18|
    JP2020516495A|2020-06-11|
    SE1750437A1|2018-10-13|
    EP3610066A4|2021-01-20|
    EP3610066A1|2020-02-19|
    US11162222B2|2021-11-02|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    JP2000303386A|1999-04-19|2000-10-31|Oji Paper Co Ltd|Moistureproof laminate with barrier properties|
    JP4009423B2|2000-12-19|2007-11-14|凸版印刷株式会社|Modified fine fibrillated cellulose and method for producing the same, paper sheet to which modified fine fibrillated cellulose is added, and coated paper using modified fine fibrillated cellulose|
    EP2371892A4|2008-12-26|2013-07-31|Kao Corp|Gas-barrier material, gas-barrier molded article, and method for producing the gas-barrier molded article|
    WO2010074341A1|2008-12-26|2010-07-01|花王株式会社|Cellulose fiber suspension and manufacturing method therefor, and film-like formed body and manufacturing method therefor|
    BR112012000269A2|2009-07-07|2016-02-16|Tetra Laval Holdings & Finance|barrier layer for a packaging laminate, packaging laminate, packaging for oxygen sensitive products, and method for making a barrier bed|
    JP5772814B2|2010-03-25|2015-09-02|凸版印刷株式会社|Gas barrier laminate and packaging material|
    JP5704165B2|2010-03-26|2015-04-22|凸版印刷株式会社|Film-forming composition and sheet|
    JP6107320B2|2013-03-29|2017-04-05|凸版印刷株式会社|Modified cellulose nanofiber, method for producing the same, gas barrier layer forming material, and gas barrier laminate|
    JP6318490B2|2013-07-25|2018-05-09|凸版印刷株式会社|Laminate|
    US10384424B2|2013-09-06|2019-08-20|Billerudkorsnäs Ab|Oxygen and water vapour barrier films with low moisture sensitivity fabricated from self-cross-linking fibrillated cellulose|
    JP6575128B2|2015-05-12|2019-09-18|凸版印刷株式会社|Method for producing cellulose nanofiber sheet|
    RU2720941C2|2015-06-30|2020-05-14|Биллерудкорснас Аб|Antioxygen protection based on modified cellulose fibers|
    EP3350369B1|2015-09-17|2019-07-24|Stora Enso Oyj|A method to produce a film comprising microfibrillated cellulose and an amphoteric polymer|GB0908401D0|2009-05-15|2009-06-24|Imerys Minerals Ltd|Paper filler composition|
    GB201019288D0|2010-11-15|2010-12-29|Imerys Minerals Ltd|Compositions|
    SE1650900A1|2016-06-22|2017-11-28|Stora Enso Oyj|Microfibrillated cellulose film|
    SE540365C2|2016-09-28|2018-08-14|Stora Enso Oyj|A method for the production of a film comprising microfibrillated cellulose, a film and a paper or paperboard product|
    SE542058C2|2017-05-18|2020-02-18|Stora Enso Oyj|A method of manufacturing a film having low oxygen transmission rate values|
    SE542443C2|2017-12-13|2020-05-05|Stora Enso Oyj|A method for manufacturing a film from microfibrillated dialdehyde cellulose and microfibrillated cellulose|
    SE543028C2|2018-10-08|2020-09-29|Stora Enso Oyj|An oxygen barrier layer comprising microfibrillated dialdehyde cellulose|
    SE543174C2|2018-10-08|2020-10-20|Stora Enso Oyj|A flexible barrier layer comprising microfibrillated dialdehyde cellulose|
    SE1950802A1|2019-06-27|2020-12-28|Stora Enso Oyj|Gas barrier film for packaging material|
    EP3822410A1|2019-11-12|2021-05-19|BillerudKorsnäs AB|Method of producing a sheet comprising chemically modified cellulose fibres|
    SE2050422A1|2020-04-15|2021-10-16|Stora Enso Oyj|Multilayer film comprising highly refined cellulose fibers|
    SE2050424A1|2020-04-15|2021-10-16|Stora Enso Oyj|Multilayer film comprising highly refined cellulose fibers|
    SE2050525A1|2020-05-07|2021-11-08|Stora Enso Oyj|Process for production of nano-coated substrate|
    法律状态:
    2021-10-19| B350| Update of information on the portal [chapter 15.35 patent gazette]|
    优先权:
    申请号 | 申请日 | 专利标题
    SE1750437A|SE540870C2|2017-04-12|2017-04-12|A gas barrier film comprising a mixture of microfibrillated cellulose and microfibrillated dialdehyde cellulose and a method for manufacturing the gas barrier film|
    SE1750437-4|2017-04-12|
    PCT/IB2018/052543|WO2018189698A1|2017-04-12|2018-04-11|A barrier film comprising microfibrillated cellulose and microfibrillated dialdehyde cellulose and a method for manufacturing the barrier film|
    [返回顶部]