JP6961790B2 - Anti-fog film - Google Patents

Description

The present invention relates to an anti-fog film.

Mirrors in bathrooms or vanities, frozen showcases, eyeglasses, ski or swimming goggles, etc., have reduced visibility due to water droplets adhering to the surface due to condensation. Therefore, an anti-fog film is used to prevent a decrease in visibility. Examples of the method for preventing the anti-fog film from deteriorating the visibility include the following methods 1 and 2. Method 1 is a method of preventing the formation of water droplets by using an anti-fog film whose film surface is made of a water-absorbing material, and the water-absorbing material absorbs water vapor. Method 2 is a method of ensuring visibility with an anti-fog film having a hydrophilic film surface. In this method 2, the adhered water is wetted and spread by the low contact angle of the film surface, which is hydrophilic, thereby forming a water film. Then, even after the water absorption capacity of the water-absorbing material according to the above method 1 is saturated, by forming a water film on the film surface by the above method 2, the amount of water vapor that becomes water droplets varies in various environments. It is possible to ensure visibility.

In order to ensure visibility in various environments, the initial anti-fog property, which is a function to prevent the formation of water droplets instantaneously, and the long-term anti-fog property, which is a function to prevent the formation of water droplets for a long time, are required. It is preferable to have. Method 1 is related to initial anti-fog and Method 2 is related to long-term anti-fog. As an anti-fog film having initial anti-fog property and long-term anti-fog property, an anti-fog film having a specific contact angle and an acyl group ratio on the surface of a film formed of cellulose acylate is disclosed (patented). Document 1). Further, an anti-fog film in which a hydrophilic agent-containing coating agent composed of a surfactant and a hydrophilic polymer is applied to a film such as polyester is disclosed (Patent Document 2). Even if it has initial anti-fog property and long-term anti-fog property, water droplets may be temporarily formed to cause fogging after the water absorption capacity of the water-absorbing material is saturated. This period during which cloudiness occurs temporarily is referred to as a "transition period". Patent Document 2 is intended to prevent fogging during the transition period.

JP-A-2017-57370 Japanese Patent Application Laid-Open No. 2011-52064

The anti-fog film of Patent Document 2 may come off due to the coating agent melting as it is used, and there is a concern about the durability of the anti-fog effect.

Therefore, an object of the present invention is to provide an anti-fog film which has both initial anti-fog property, long-term anti-fog property, and anti-fog property during a transition period, and has excellent durability of these anti-fog properties.

In order to solve the above problems, the anti-fog film of the present invention has a film base material, a first layer and a second layer. The film substrate is formed of a cellulose acylate having an acyl group substitution degree in the range of 2.00 or more and 2.97 or less. The first layer is formed of cellulose acylate or cellulose having a lower degree of acyl group substitution than the film substrate and is provided on one surface of the film substrate. The second layer contains a resin component having a molecular weight of 30,000 or more, and is provided on the surface of the first layer opposite to the surface in contact with the film substrate. The resin component has any one of a hydroxy group, an amide structure, and a pyrrolidone structure, the first layer has a thickness in the range of 0.5 μm or more and 20 μm or less, and the second layer has a thickness. The size is within the range of 1 μm or more and 20 μm or less. The resin component having a hydroxy group is a cellulose derivative having a hydroxy group and having a group that ether-bonds with cellulose, and the resin component having an amide structure is a polyamide or a polyacrylamide, and has a pyrrolidone structure. The resin component having is a polymer having a vinylpyrrolidone structure.

The resin component having a hydroxy group is preferably hydroxyethyl cellulose or carboxymethyl cellulose. The resin component having a hydroxy group is preferably carboxymethyl cellulose.

The resin component having an amide structure is preferably polyacrylamides. The resin component having a pyrrolidone structure is preferably a polymer obtained by copolymerizing a vinylpyrrolidone compound with vinyl acetate and / or an acrylic derivative. It is preferable that the resin component having a pyrrolidone structure is a polymer obtained by copolymerizing a vinylpyrrolidone compound and vinyl acetate in a mass portion of vinylpyrrolidone compound: vinyl acetate in a proportion of 7: 3.

The anti-fog film of the present invention has initial anti-fog property, long-term anti-fog property, and anti-fog property during the transition period, and these anti-fog properties are excellent in durability.

It is sectional drawing of the anti-fog film. It is the schematic of the anti-fog film manufacturing apparatus. It is the schematic of the anti-fog film manufacturing apparatus. It is explanatory drawing explaining an example of application of an anti-fog film.

The anti-fog film of the present invention includes a film base material, a first layer (hereinafter referred to as an intermediate layer), and a second layer (hereinafter referred to as a resin layer). As shown in FIG. 1, the anti-fog film 10 is a laminated film in which a film base material 11, an intermediate layer 12, and a resin layer 13 are provided by a laminated structure in this order. The shape of the anti-fog film 10 is not limited, and may be a long shape or a sheet shape such as a rectangle. Further, the anti-fog film 10 may have another layer.

The thickness T10 of the anti-fog film 10 is preferably in the range of 10 μm or more and 220 μm or less. More preferably, it is in the range of 20 μm or more and 180 μm or less, and further preferably, it is in the range of 40 μm or more and 150 μm or less. When the thickness T10 is within the range of 10 μm or more and 220 μm or less, a layer having the film base material 11, the intermediate layer 12, and the resin layer 13 can be formed, and the anti-fog film 10 can be used as a mirror or a freezing showcase. It is preferable because it is easy to handle when it is attached to a film or attached to eyeglasses, goggles, etc.

The film base material 11 is a layer that is a base of the anti-fog film 10, and functions as a support that supports the intermediate layer 12 and the resin layer 13. The film substrate 11 is formed of cellulose acylate. The film base material 11 absorbs water and releases water by changing the temperature and humidity according to the equilibrium water content of cellulose acylate. The cellulose acylate is cellulose triacetate (triacetyl cellulose, hereinafter referred to as TAC) in the present embodiment, but is not limited to TAC, and may be another cellulose acylate different from TAC. In the film base material 11, the surface in contact with the intermediate layer 12 is one surface 11a, and the surface on the opposite side is the other surface 11b.

Cellulose acylate has an acyl group because the hydroxy group of cellulose is esterified with a carboxylic acid. As is well known, the rate at which the hydroxy group of cellulose is esterified with a carboxylic acid, that is, the degree of substitution of the acyl group is defined as the degree of substitution of the acyl group. The degree of acyl group substitution of cellulose acylate contained in the film substrate 11 is in the range of 2.00 or more and 2.97 or less. When the degree of acyl group substitution is within the above range, deformation of the film base material 11 due to water absorption is suppressed. The smaller the degree of acyl group substitution, the higher the amount of water absorbed by cellulose acylate, so that it is easily deformed by water absorption. Therefore, the degree of acyl group substitution of the cellulose acylate contained in the film base material 11 is 2.00 or more. On the other hand, cellulose acylate having an acyl group substitution degree of more than 2.97 is difficult to synthesize. Therefore, the degree of acyl group substitution is 2.97 or less. The degree of acyl group substitution of the cellulose acylate contained in the film substrate 11 is preferably in the range of 2.40 or more and 2.95 or less, and more preferably in the range of 2.70 or more and 2.95 or less.

The acyl group of the cellulose acylate constituting the film base material 11 is not particularly limited, and may be an acetyl group having 1 carbon atom or an acyl group having 2 or more carbon atoms. The acyl group having 2 or more carbon atoms may be an aliphatic group or an aryl group, and examples thereof include an alkylcarbonyl ester of cellulose, an alkenylcarbonyl ester or an aromatic carbonyl ester, and an aromatic alkylcarbonyl ester. It may also have a substituted group. Propionyl group, butanoyl group, pentanoyl group, hexanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, hexadecanoyl group, octadecanoyl group, iso-butanoyl group, t-butanoyl group, cyclohexane Examples thereof include a carbonyl group, an oleoil group, a benzoyl group, a naphthylcarbonyl group, and a cinnamoyl group.

The acyl group of the cellulose acylate constituting the film base material 11 may be only one kind or two or more kinds, but it is preferable that at least one kind is an acetyl group. Since the cellulose acylate has an acetyl group, the film base material 11 easily absorbs water, so that the water content effect and the like are improved. Most preferably, it is a cellulose acylate in which all the acyl groups are acetyl groups, that is, it is more preferable that the cellulose acylate is cellulose acetate.

The degree of acyl group substitution can be determined by a conventional method. For example, the degree of acetylation (degree of acetyl group substitution) is determined according to the measurement and calculation of the degree of acetylation in ASTM: D-817-91 (test method such as cellulose acetate). It can also be measured by measuring the degree of acylation (degree of acyl group substitution) distribution by high performance liquid chromatography. As an example of this method, the degree of acetylation of cellulose acetate is measured by dissolving a sample in methylene chloride, using a column, Novapac-phenyl (manufactured by Waters), and using a mixed solution of methanol and water as an eluent (methanol: water). The acetylation degree distribution was measured by a linear gradient from 8: 1) to a mixed solution of dichloromethane and methanol (methylene: methanol mass ratio of 9: 1), and calibration was performed using standard samples with different acetylation degrees. Obtained by comparison with the line. These measuring methods can be obtained by referring to the methods described in JP-A-2003-201301. When the cellulose acylate is collected from the film substrate 11, the degree of acetylation is preferably measured by high performance liquid chromatography because it contains the following additives.

The degree of substitution of the acyl group can be changed by adjusting the degree of substitution of the acyl group with the hydroxy group of cellulose. Substitution of the acyl group with the hydroxy group of cellulose generally includes a method using an acid anhydride and a mixed acid anhydride. Of these, the basic principle of the method for synthesizing cellulose acetate is described in "Wood Chemistry" by Umeda et al. (Kyoritsu Shuppan, 1968, pp. 180-190). A typical synthesis method is a liquid phase vinegarization method using an acetic anhydride-acetic acid-sulfuric acid catalyst. Specifically, after pretreating a cellulose raw material such as wood pulp or cotton linter with an appropriate amount of acetic acid, it is added to a pre-cooled vinegared mixture to acetic acid esterify, and complete cellulose acetate (2nd, 3rd and 6th). The total degree of acetyl substitution at the position synthesizes approximately 3). The vinegar mixture generally contains acetic acid as a solvent, acetic anhydride as an esterifying agent and sulfuric acid as a catalyst. Acetate anhydride is usually used in a chemically excessive amount rather than the total amount of cellulose reacting with it and the water present in the system, so that it remains in the system after the completion of the tanning reaction. Hydrolysis of excess anhydrous acetic acid and some neutralization of the esterification catalyst is carried out with a neutralizing agent (eg, calcium, magnesium, iron, aluminum or zinc carbonate, acetate or oxide). The resulting complete cellulose acetate is then saponified and aged in the presence of a small amount of vinegaring reaction catalyst (generally the remaining sulfuric acid) to change to cellulose acetate with a particular degree of acetyl substitution and degree of polymerization. When a particular cellulose acetate is obtained, the catalyst remaining in the system is completely neutralized with a neutralizer as described above, or in water or dilute sulfuric acid without neutralization. Cellulose acetate solution is put into the water to separate the cellulose acetate, and the cellulose acetate is obtained by washing and stabilization treatment.

The film base material 11 can contain, as an additive, a plasticizer, an ultraviolet absorber, fine particles as a so-called matting agent for preventing the film base materials 11 from sticking to each other, and the like. As the additive, various known additives can be used. Examples of the plasticizer include triphenyl acetate (TPP), biphenyl diphenyl phosphate (BDP), an ester derivative of a sugar, an ester oligomer, and an acrylic polymer. Further, as the ultraviolet absorber, any known one that can exhibit ultraviolet absorption can be used, and examples thereof include an ultraviolet absorber having a benzophenone skeleton, a benzotriazole skeleton, a triazine skeleton and the like. By adjusting the type and amount of the additive, the water content of the film base material 11 can be adjusted, and the thickness of the intermediate layer formed by the saponification treatment can be adjusted. As a result, the water contained in the resin layer 13 is transferred to the intermediate layer 12 and the film base material 11, and the resin layer 13 can be suppressed from falling off to improve the durability of the anti-fog effect, and the intermediate layer 12 and the film can be improved. Anti-fog property can be improved by improving the water absorption capacity of the base material 11. Preferred additives include ester derivatives of sugars and ester oligomers. The content of these additives is preferably in the range of 1 or more and 50 or less, and more preferably in the range of 2 or more and 30 or less, when the mass of cellulose acylate is 100.

The thickness T11 of the film base material 11 is preferably in the range of 8 μm or more and 210 μm or less, preferably in the range of 30 μm or more and 200 μm or less. When the thickness T11 is in the range of 8 μm or more and 210 μm or less, it is easy to handle as an anti-fog film, which is preferable.

The intermediate layer 12 is a cellulose acylate or cellulose layer having an acyl group substitution degree smaller than that of the film substrate 11. In the present embodiment, as described later, the intermediate layer 12 is formed by saponifying one surface 14a of the TAC film 14 (see FIG. 2), which is the base film 11, so that the intermediate layer 12 is a film base. It is provided on one surface 11a of the material 11. A saponified TAC is formed in the intermediate layer 12.

The intermediate layer 12 is formed by a saponification treatment which is an alkaline hydrolysis reaction of cellulose acylate, and the acyl group contained in TAC becomes a hydroxy group by a substitution reaction, and the acyl group is reduced. That is, the degree of acyl group substitution in the TAC film 14 (see FIG. 2), that is, the degree of acyl group substitution in the intermediate layer 12 is smaller than the degree of acyl group substitution in the film substrate 11. And the intermediate layer 12 made of cellulose acylate having more hydroxy groups has higher water absorption.

The degree of acyl group substitution of the intermediate layer 12 depends on the degree of acyl group substitution of the film base material 11, but is preferably 1.50 or less. If the degree of acyl group substitution in the intermediate layer 12 is larger than 1.50, the proportion of acyl groups is large, and the water absorption may not be sufficient. The lower limit of the degree of acylation substitution of the intermediate layer 12 is 0. When the degree of acyl group substitution is 0, it means cellulose, but the intermediate layer 12 can also be formed of cellulose.

Since the intermediate layer 12 is configured as described above, when the resin layer 13 forming the surface of the anti-fog film 10 contains water, the intermediate layer 12 in contact with the resin layer 13 absorbs water from the resin layer 13. The water content of the resin layer 13 is reduced. As a result, it is possible to prevent the resin layer 13 from flowing down or falling off due to excessive water content of the resin layer 13.

The thickness T12 of the intermediate layer 12 is preferably in the range of 0.5 μm or more and 20 μm or less, and more preferably in the range of 2 μm or more and 15 μm. When the thickness T12 is 0.5 μm or more, the action of reducing the water content of the resin layer 13 can be more sufficiently exerted by the water absorption of the intermediate layer 12 as compared with the case where the thickness T12 is less than 0.5 μm. Therefore, it is preferable. On the other hand, the intermediate layer 12 thicker than 20 μm is difficult to form. The thickness T12 is obtained by the following method in this embodiment. A sample sampled from a material composed of the film base material 11 and the intermediate layer 12 obtained by saponifying the film base material 11 is immersed in dichloromethane for 24 hours. The sample left undissolved by this immersion is dried, and the thickness of the dried sample is measured three times. The average of the three measured values is the thickness T12.

The resin layer 13 (see FIG. 1) contains a resin component having a molecular weight of 30,000 or more, and the resin component is a layer having any one of a hydroxy group, an amide structure, and a pyrrolidone structure. Further, the resin layer 13 is formed on one surface 12a of the intermediate layer 12 and constitutes the outermost layer of the anti-fog film 10. The resin layer 13 is formed of a hydrophilic polymer. Therefore, the resin layer 13 absorbs water vapor that can be water droplets near the surface of the anti-fog film 10 and has an initial anti-fog property. In addition, a water film is formed immediately after the initial anti-fog property is saturated to prevent water droplets from adhering during the transition period. Further, moisture moves from the resin layer 13 to the intermediate layer 12 to exhibit long-term anti-fog property. Further, since the resin layer 13 has an affinity with the intermediate layer 12, for example, it prevents the resin layer 13 from flowing down or falling off due to water content. Further, the water contained in the resin layer 13 moves to the intermediate layer 12, and the water content of the resin layer 13 can be kept low, and since the molecular weight is 30,000 or more, it is difficult to run off with water. Furthermore, since the resin layer 13 is formed of a specific hydrophilic polymer and its solubility in water is suppressed, it is difficult for the resin layer 13 to run off due to water content. Therefore, the resin layer 13 has durability in anti-fog property.

The resin layer 13 contains a polymer having any one of a hydroxy group, an amide structure, and a pyrrolidone structure, and having a molecular weight of 30,000 or more. In addition, in this specification, an amide structure means a structure represented by -C (= O) -NH-. The pyrrolidone structure refers to a structure represented by the following formula (1).

The polymer having the above group or structure may include these groups or structures in the polymer. For example, these groups or structures are the main chain, side chain and graft polymerization of the polymer. It means that it is contained in any of chains and the like.

Examples of the polymer having a hydroxy group include celluloses, polyvinyl alcohols, and a hydroxy group-containing acrylic polymer. Specifically, celluloses such as cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), hydroxypropyl cellulose (HPC); polyvinyl alcohol, polyvinyl alcohol by partial saponification of polyvinyl acetate, polyacetic acid. Polyvinyl alcohols such as vinyl copolymers; acrylic polymers such as hydroxyethyl acrylate or hydroxyl group-containing acrylic polymers such as copolymers can be mentioned.

Of these, a cellulose derivative having a hydroxy group and having a group that ether-bonds with cellulose is preferable. Specific examples thereof include methyl cellulose, ethyl cellulose, hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), hydroxypropyl cellulose (HPC) and the like. Since cellulose has a high ratio of hydroxy groups per cellulose constituent unit, it is easy to form a water film on the surface, and by having a hydrocarbon group ether-bonded to cellulose, the solubility of the cellulose derivative itself in water is suppressed, and the initial stage It has improved anti-fog properties and excellent anti-fog durability. Of these, hydroxyethyl cellulose (HEC) or hydroxypropyl cellulose (HPC) is preferable. As hydroxyethyl cellulose (HEC), either an aqueous solution or a powder can be used.

Examples of the polymer having an amide structure include polyamides and polyacrylamides. Specifically, it is obtained by polycondensation of nylon 6, hexamethylenediamine and adipic acid obtained by ring-opening polymerization of ε-caprolactam. Polyamides such as nylon 66; polyacrylamides such as acrylamide polymers or copolymers with other acrylic derivatives can be mentioned. Of these, an acrylamide resin copolymerized with highly hydrophilic acrylamide and another acrylic derivative that suppresses solubility in water is preferable because it has good antifog effect durability. In the case of an acrylamide resin obtained by copolymerizing an acrylic derivative that suppresses water solubility and acrylamide, the amount of acrylamide is preferably in the range of 40 parts by mass or more and 95 parts by mass or less.

Specific examples of the polymer having a pyrrolidone structure include polymers composed of vinylpyrrolidone compounds such as N-vinyl-2-pyrrolidone and N-vinylethyl-2-pyrrolidone. Of these, a polymer having a vinylpyrrolidone structure is preferable. Examples of the polymer having a vinylpyrrolidone structure include vinylpyrrolidone compounds, for example, polymers polymerized using the above-mentioned N-vinyl-2-pyrrolidone and N-vinylethyl-2-pyrrolidone as monomers, as well as vinylpyrrolidone compounds and others. It may be a copolymer with the monomer of. Of these, a polymer obtained by copolymerizing a vinylpyrrolidone compound with at least one compound selected from the group consisting of vinyl acetate and an acrylic derivative is preferable. The acrylic derivative to be copolymerized may be any acrylic derivative that copolymerizes with a vinylpyrrolidone compound to form a polymer. Specifically, for example, acrylic acid; methacrylic acid; acrylic acid such as methyl acrylate and ethyl acrylate. Alkyl esters; Examples thereof include alkyl esters of methacrylic acid such as methyl methacrylate and ethyl methacrylate. Polyvinylpyrrolidone having a pyrrolidone structure has a high affinity for cellulose acylate or cellulose in the intermediate layer 12, and is excellent in durability of antifogging effect. Further, vinyl acetate having a highly hydrophilic pyrrolidone structure and capable of suppressing solubility in water, or a polymer copolymerized with another acrylic derivative is also preferable, and N-vinyl-2-pyrrolidone and vinyl acetate are used. Copolymers are particularly preferred. In the case of a polymer having a pyrrolidone structure copolymerized with vinyl acetate or another acrylic derivative that suppresses water solubility, the component having a pyrrolidone structure must be in the range of 40 parts by mass or more and 95 parts by mass or less. preferable. The above polymer may be contained in the resin layer 13 in combination of one type or two or more types.

In the resin layer 13, it is also preferable to add an additive that enhances the interaction between the polymers to the polymer having any one of the hydroxy group, the amide structure, and the pyrrolidone structure. As such an example, a method of adding an additive that bonds or interacts with a hydrophilic group such as a hydroxy group, or if the polymer has an ionic group such as a carboxy group, an acid is added to dissociate the ion. Examples thereof include a method of enhancing the interaction between ionic groups by suppressing the reaction. Specific examples thereof include a method of adding an acid such as citric acid to a polymer having a hydroxy group and a carboxy group such as carboxymethyl cellulose. In such a method, the formability of a water film on the surface due to the hydroxy group and the anti-fog durability due to the interaction between the carboxy group of the polymer and the citric acid component are excellent.

The polymer contained in the resin layer 13 has a molecular weight of 30,000 or more. The molecular weight is the number average molecular weight determined by GPC in a polymer that can be determined by gel permeation chromatography (GPC), and in a polymer in which it is difficult to determine the molecular weight by GPC, for example, polyvinylpyrrolidone. , The viscosity average molecular weight obtained from the measured value of capillary viscosity. The molecular weight is preferably in the range of 30,000 or more and 20000 or less. More preferably, it is in the range of 35,000 or more and 180,000 or less, and particularly preferably, it is in the range of 40,000 or more and 1500,000 or less. When the molecular weight of the polymer is in the range of 30,000 or more and 20000,000 or less, the water contained in the resin layer 13 moves to the intermediate layer 12 and keeps the water in the resin layer 13 low, so that it becomes difficult to run off with water. It has excellent anti-fog durability and is preferable.

The thickness T13 (see FIG. 1) of the resin layer 13 is preferably in the range of 1 μm or more and 20 μm or less. It is more preferably in the range of 2 μm or more and 18 μm or less, and particularly preferably in the range of 5 μm or more and 15 μm or less. When the thickness T13 (see FIG. 1) is within the range of 1 μm or more and 20 μm or less, the effect of the resin layer 13 such as long-term anti-fog property is sufficiently exhibited, and the anti-fog film 10 sufficiently exhibits the anti-fog property. preferable. Further, it is preferable because water easily permeates into the intermediate layer 12 and the water absorption action of the intermediate layer 12 is sufficiently exhibited. When the thickness T13 is thicker than 20 μm, it is considered that the resin layer 13 flows down and falls off due to the water content, and the thickness T13 is reduced to the above range. In this case, as a matter of course, the anti-fog film which exerts the effect as the anti-fog film 10 of the present invention and exhibits the anti-fog property in all of the initial anti-fog property, the long-term anti-fog property, and the transition period. It becomes 10.

In the present embodiment, the intermediate layer 12 is formed by the intermediate layer forming device 16. The intermediate layer forming apparatus 16 shown in FIG. 2 is an apparatus for continuously forming an anti-fog film material 18 composed of a film base material 11 and an intermediate layer 12, which is a part of the anti-fog film 10.

The intermediate layer forming device 16 includes a delivery machine 20, a saponification unit 22, a drying device 24, and a winding machine 26 in order from the upstream side in the transport direction of the anti-fog film material 18. The intermediate layer forming device 16 further includes a roller 36. Although a plurality of rollers 36 are provided, only two are shown in FIG. The roller 36 supports the TAC film 14 or the antifogging film material 18 from below on the peripheral surface, and rotates around the rotation axis to convey the TAC film 14 or the antifogging film material 18.

The TAC film 14 is manufactured by a film forming apparatus (not shown) by a well-known solution film forming method. Specifically, in the above-mentioned film forming apparatus, a polymer solution containing TAC (hereinafter referred to as dope) is cast on a support to form a cast film, and the cast film is peeled off from the support and dried. By doing so, it is made long. The dope is adjusted from TAC, additives added as needed, solvents and the like.

The feeder 20 is for continuously feeding the long TAC film 14. The TAC film 14 is set in the transmitter 20 in a state of being wound around the winding core 28 in a roll shape, and the TAC film 14 is continuously delivered by rotating the winding core 28.

The saponification unit 22 is for making the anti-fog film material 18 by continuously saponifying the TAC film 14. The saponification unit 22 includes a coating device 30, an infrared heater 32, and a cleaning device 34.

The coating device 30 is for coating the saponifying liquid 38 on one surface 14a of the TAC film 14. The coating device 30 continuously flows out the supplied saponification liquid 38 from the outlet 30a facing one surface 14a. The coating device 30 continuously flows out the saponifying liquid 38 onto the TAC film 14 being conveyed, so that the saponifying liquid 38 is continuously coated on one surface 14a. Examples of the saponification treatment method include a method of applying the saponification liquid 38 by coating as in the present embodiment, and a method of applying the saponification liquid 38 by immersion. The layer formed by saponifying the TAC film 14 (see FIG. 2) is the intermediate layer 12 (see FIG. 1), and the remaining TAC film not saponified by this saponification treatment is the film substrate 11 (see FIG. 1). See). Therefore, the film substrate 11 does not contain the saponified TAC, and the intermediate layer 12 contains the saponified TAC.

The saponifying liquid 38 is for saponifying one surface of the TAC film 14 to form an intermediate layer 12 (see FIG. 1), and contains an alkali. The alkali is potassium hydroxide (KOH) in this embodiment, but is not limited to this, and sodium hydroxide (NaOH) may be used instead of KOH. In this example, the saponification solution 38 contains a solvent in addition to the alkali. Solvents include water and organic solvents. As the organic solvent, one or more selected from the group consisting of alcohols, ethers, amides, and sulfoxides can be used. As the alcohols, alcohols having 2 or more and 8 or less carbon atoms are preferable. Examples of alcohols having 2 or more and 8 or less carbon atoms include ethanol, isopropyl alcohol, 1-propanol, 1-butanol, hexanol, ethylene glycol, glycerin, propylene glycol, butylene glycol, pentaerythritol and the like. Of these, isopropyl alcohol is particularly preferable, and isopropyl alcohol is also used in this embodiment. Examples of ethers include diethyl ether, diethylene glycol, dipropylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether and the like. Examples of amides include N, N-dimethylformamide, dimethylacetamide and the like. Examples of sulfoxides include dimethyl sulfoxide and the like.

The organic solvent has an action of promoting the penetration of alkali into the TAC film 14 in addition to the action as a solvent. In this example, alcohol is used, and alkali and alcohol are applied by applying the saponifying solution 38. The present invention is not limited to this embodiment, and for example, a method of sequentially applying an aqueous solution of alcohol and an alkali may be used. In this case, it is more preferable to apply the saponifying solution after applying the alcohol.

Alcohol is applied to one surface 14a in ^{an amount of at least 17 g per 1 m 2} of area of one surface 14a, that is, in an amount of 17 g / m ² or more. The coating amount of the alcohol is more preferably it is preferably in the range of 17 g / m ² or more 39.6 g / m ² or less, in the range of 22 g / m ² or more 39.6 g / m ² or less, 33 It is more preferably in the range of .4 g / m ² or more and 39.6 g / m ^{2 or less.}

Alkali is applied to one surface 14a in ^{an amount of at least 0.3 g per 1 m 2} of area of one surface 14a, that is, in an amount of 0.3 g / m ² or more. As a result, the alkali penetrates into the film base material 11 reliably and quickly. The amount of alkaline alcohol applied ^{is preferably in the range of 0.3 g / m 2} or more and 1.3 g / m ² or less, and is in the range of 0.6 g / m ² or more and 1.3 g / m ² or less. More preferably, it is more preferably in the range of ^{0.7 g / m 2} or more and 1.3 g / m ^{2 or less.}

The infrared heater 32 is for keeping the TAC film 14 within a predetermined temperature range for a predetermined time by heating the TAC film 14. The infrared heater 32 is provided so that the emission surface for emitting infrared rays faces the TAC film 14 to be conveyed. The infrared heater 32 may be arranged so as to face one surface 14a on which the coating film 40 formed from the saponifying liquid 38 is formed, but the alkali is more reliably and more reliably applied from the one surface 14a side. From the viewpoint of efficient penetration, it is preferable that the film is arranged so as to face the other surface 14b, which is the film surface opposite to one surface 14a, as in the present embodiment shown in FIG.

Instead of or in addition to the infrared heater 32, a blowing type blower that blows a heated gas onto the TAC film 14 or a chamber surrounding the transport path of the TAC film 14 with a heated gas in the chamber. A chamber type blower to be supplied may be used.

In order to improve the initial anti-fog property, one surface 14a is held at a temperature of 40 ° C. or higher and 80 ° C. or lower for a time of 20 seconds or more and 120 seconds or less by heating with an infrared heater 32. By keeping the temperature at 40 ° C. or higher, saponification proceeds more quickly than when the temperature is lower than 40 ° C., and an intermediate layer 12 having a larger thickness T12 is formed, so that initial antifogging property is surely exhibited. do. By keeping the temperature below 80 ° C., the evaporation of alcohol is surely suppressed and the intermediate layer 12 is surely formed as compared with the case where the temperature is higher than 80 ° C. The holding temperature is more preferably in the range of 40 ° C. or higher and 70 ° C. or lower, and further preferably in the range of 50 ° C. or higher and 70 ° C. or lower.

The time for holding in the above temperature range is 20 seconds or more and 120 seconds or less. By setting the time to 20 seconds or more, saponification proceeds more quickly than in the case of less than 20 seconds, and the intermediate layer 12 having a larger thickness T12 (see FIG. 1) is formed, so that the water supply capacity is improved. Expressed clearly. Within 120 seconds, a saponified layer having an appropriate thickness can be formed. The time for holding in the above temperature range is more preferably 30 seconds or more and 100 seconds or less, and further preferably 30 seconds or more and 50 seconds or less.

The cleaning device 34 is for stopping saponification by cleaning the TAC film 14. The cleaning device 34 includes a spray-type cleaning machine that sprays water onto one surface 14a on which the coating film 40 is formed. By spraying water, the alkali is quickly removed from the TAC film 14.

An intermediate layer 12 is formed on the TAC film 14 that has passed through the cleaning device 34, and the TAC film 14 is guided to the drying device 24 to be dried. As the drying device, in the present embodiment, a chamber type drying device is used in which the transport path is surrounded by a chamber and the heated gas is supplied to the chamber, but the drying device is not particularly limited. By this drying, the contained water evaporates, and the anti-fog film material 18 is obtained in a long length. The anti-fog film material 18 is guided by the winder 26 and wound around the set winding core 42 in a roll shape. After being wound around the winding core 42, it is sent to the resin layer forming apparatus 44 (see FIG. 3). In the resin layer forming apparatus 44 (see FIG. 3), the anti-fog film material 18 wound around the winding core 42 is provided, and the resin layer 13 is formed on one surface 12a of the anti-fog film material 18. The anti-fog film 10 is manufactured.

The resin layer 13 (see FIG. 1) is provided on one surface 12a (see FIG. 1) opposite to the other surface 12b (see FIG. 1) in contact with the film base material 11 among the surfaces of the intermediate layer 12. As a method for forming the resin layer 13, any method can be applied as long as it can be formed on one surface 12a without impairing the functions of the film base material 11 and / or the intermediate layer 12. Therefore, for example, the coating composition 41 containing the polymer forming the resin layer 13 may be formed by coating on one surface 12a, or a film formed from the coating composition 41 or the like may be formed. , May be formed by sticking to one surface 12a. The resin layer 13 is well formed with no risk of peeling from the intermediate layer 12. Since it is composed of the resin layer 13 and the intermediate layer 12 as described above, it is considered that they have an affinity and are firmly bonded to each other.

In the present embodiment, the resin layer 13 is formed by applying the coating composition 41 prepared for coating to one surface 12a. The resin layer 13 can be manufactured by the resin layer forming apparatus 44 shown in FIG. The resin layer forming apparatus 44 shown in FIG. 3 is an apparatus for forming the resin layer 13 on the above-mentioned anti-fog film material 18 (see FIG. 2) to continuously produce the anti-fog film 10. The intermediate layer forming apparatus 16 for producing the anti-fog film material 18 and the resin layer forming apparatus 44 for producing the anti-fog film 10 by forming the resin layer 13 on the anti-fog film material 18 are used separately, so to speak. , The anti-fog film 10 may be continuously produced by connecting these devices and continuously using them.

Further, the coating composition 41 is applied to a sheet of a long anti-fog film material 18 cut into sheets by a product or the like finally produced by the anti-fog film 10. You can also. Examples of the above means include bar coating, geser coating, spin coating and the like. Further, the coating composition 41 is cut into sheets, and the coating composition 41 is dipped in a cloth and applied to the anti-fog film 10 and then dried, or spread uniformly with a dry cloth. It can also be applied by such a method.

The resin layer forming device 44 includes a sending machine 46, a resin layer forming unit 48, a drying device 49, and a winding machine 51 in order from the upstream side in the transport direction of the antifog film 10.

The delivery machine 46 continuously sends out a long anti-fog film material 18. The anti-fog film material 18 is set in the feeder 46 in a state of being wound around the winding core 42 in a roll shape, and the anti-fog film material 18 is continuously sent out by rotating the winding core 42.

The resin layer forming unit 48 is for forming the resin layer 13 continuously on one surface 12a of the anti-fog film material 18. The resin layer forming unit 48 includes a coating device 50, an infrared heater 52, and a roller 54. Although a plurality of rollers 54 are provided, only one is shown in FIG. The roller 54 supports the anti-fog film material 18 from below on the peripheral surface and rotates around the rotation axis to convey the anti-fog film material 18.

The coating device 50 is for coating the coating composition 41 for forming the resin layer 13 on one surface 12a of the anti-fog film material 18 on the intermediate layer 12 side. The coating device 50 continuously flows out the supplied coating composition 41 from the outlet 50a facing one surface 12a. In addition, in FIG. 3, the coating composition 41 is described as "composition". The coating device 50 continuously flows out the coating composition 41 onto the anti-fog film material 18 being conveyed, so that the coating composition 41 is continuously coated on one surface 12a.

The infrared heater 52 is for curing the composition contained in the coating composition 41 by heating the anti-fog film material 18. The infrared heater 52 is provided so that the injection surface that emits infrared rays faces the anti-fog film material 18 to be conveyed. The infrared heater 52 may be arranged so as to face one surface 12a on which the coating film 56 formed from the coating composition 41 is formed, and as in the present embodiment shown in FIG. It may be arranged so as to face the other surface 11b of the film base material 11, which is the film surface opposite to the surface 12a.

An intermediate layer forming device 16 (see FIG. 2) described above may use a blower, a chamber type blower, or the like for the anti-fog film material 18 instead of or in addition to the infrared heater 52. It is the same as explained in.

A resin layer 13 is formed on the anti-fog film material 18 that has passed through the infrared heater 52, and the anti-fog film material 18 is guided to the drying device 49 to be dried. As the drying device, the chamber type drying device is used in the present embodiment as described above, but the drying device is not particularly limited. By this drying, the contained solvent evaporates, and the anti-fog film 10 is obtained in a long length. The anti-fog film 10 is guided by the winder 51 and wound around the set winding core 58 in a roll shape. The order in which the intermediate layer 12 and the resin layer 13 are formed on the film base material 11 is not limited to this. For example, the film base material 11, the intermediate layer 12, and the resin layer 13 may be formed as independent films, and the film base material 11 may be attached after the intermediate layer 12 is attached to the resin layer 13. Alternatively, the film base material 11, the intermediate layer 12, and the resin layer 13 may be laminated at the same time.

As shown in FIG. 4, in the anti-fog film-attached glass 60, which is an example of the method of using the anti-fog film 10 of the present embodiment, the anti-fog film 10 is attached to one surface of the plate glass 62 via the adhesive layer 64. After cutting, it is pasted. Examples of the adhesive layer 64 include an acrylic pressure-sensitive adhesive, a silicon-based pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, and the like, and in the present embodiment, the acrylic-based pressure-sensitive adhesive is used. The flat glass 62 is a so-called float glass having a thickness of 5 mm. For example, by using this glass as a mirror in a bathroom, it is possible to obtain a mirror that exhibits a sufficient anti-fog effect in all various environments that require anti-fog.

As described above, the anti-fog film 10 of the present invention has a structure in which the film base material 11, the intermediate layer 12, and the resin layer 13 are combined, and therefore, the anti-fog film 10 exerts the following actions. .. That is, since the film base material 11 is formed of a specific cellulose acylate, it is excellent as a support for other layers because it absorbs water and releases water with little deformation. Then, since the intermediate layer 12 is formed of a specific cellulose acylate or cellulose, it exhibits excellent water absorption. Further, since it interacts with the film base material 11 and the resin layer 13 in contact with the intermediate layer 12, the anti-fog film 10 composed of these layers has excellent durability. Since the resin layer 13 is formed of a hydrophilic polymer having a specific molecular weight, the intermediate layer 12 and the film base material 11 suppress the run-off due to excessive water content, and have long-term antifogging durability. Has sex. Therefore, the anti-fog film 10 has excellent initial anti-fog property due to water absorption, has anti-fog property during the transition period due to the resin layer 13, and has excellent long-term anti-fog property, and thus has anti-fog performance. Excellent. Further, each layer is kept strong, the anti-fog film 10 itself is less deformed, and for example, the resin layer 13 can be suppressed from falling off due to the deformation, and the film has durability.

Further, since the resin layer 13 has a polymer having a vinylpyrrolidone structure, a polymer having an amide structure, or a specific cellulose derivative, both the hydrophilicity performance and the strength of the resin layer 13 are excellent. Further, since the resin layer 13 is made of a copolymer of a vinylpyrrolidone compound and a specific compound, the hydrophilicity performance and the strength are particularly improved.

Further, when the thickness of the intermediate layer 12 is within the above-mentioned specific range, when the above three layers are combined, the anti-fog film 10 exhibits more reliable anti-fog performance in various environments. preferable.

Further, in the anti-fog film 10, the combination of the thickness of each layer depending on the application depends on the material of each layer, but as an example, the combination of the film base material 11 is 38 μm, the intermediate layer 12 is 2 μm, and the resin layer 13 is 5 μm. Is for attaching to mirrors of vanity that requires easy handling, and the combination of film base material 11 of 115 μm, intermediate layer 12 of 10 μm, and resin layer 13 of 10 μm is attached to bathroom mirrors that require anti-fog performance. The combination of the film base material 11 of 180 μm, the intermediate layer 12 of 15 μm, and the resin layer 13 of 10 μm can be selected depending on the use for eyeglasses and goggles that require strength, and the anti-fog property and the anti-fog film handleability depending on the application. Further, in the application of bonding to a frozen showcase, it is preferable to use a cellulose derivative for the resin layer 13 because the freezing anti-fog performance is good. The freezing and anti-fog performance refers to the anti-fog performance in a low temperature environment such as a freezer, which will be described later.

Hereinafter, examples of the present invention and comparative examples with respect to the present invention will be given.

[Manufacturing example]
A TAC film having a width of 1.5 m was produced by a solution film forming apparatus (not shown), and a length of 2000 m was wound by a winder and used in Examples. The formulation of dope, which is the material of the TAC film, is as follows. The following solid content is a solid component constituting the TAC film.
1st component of solid content 100 parts by mass 2nd component of solid content 15 parts by mass 3rd component of solid content 1.3 parts by mass Dichloromethane (1st component of solvent) 635 parts by mass Methanol (2nd component of solvent) 125 parts by mass Department

The first component of the solid content is cellulose acylate, in which all acyl groups are acetyl groups and the viscosity average degree of polymerization is 320. The degree of acyl group substitution of cellulose acylate is 2.86.

The second component of the solid content is a plasticizer. The plasticizer is an oligomer having an ester of adipic acid and ethylene glycol as a repeating unit (molecular weight is 1000 by the terminal functional group quantification method). The third component of the solid content is fine particles of silica, which is R972 manufactured by Nippon Aerosil Co., Ltd.

The dope was made by the following method. First, the first component of the solid content, the second component, and the solvent which is a mixture of dichloromethane and methanol are each put into a closed container, and the mixture is stirred in the closed container while maintaining the temperature at 40 ° C. , The first component and the second component of the solid content were dissolved in a solvent. The third component of the solid content is dispersed in a mixture of dichloromethane and methanol, and the obtained dispersion is placed in the above-mentioned closed container containing a solution in which the first component and the second component of the solid content are dissolved. Dispersed. The dope thus obtained is allowed to stand, filtered through a filter paper while maintaining the temperature at 30 ° C., defoamed, and then flowed in a solution film forming apparatus (not shown). It was offered to the public.

A dope at 30 ° C. was cast from the casting die to form a casting film. The cast film immediately after formation was blown with air at 100 ° C. by a blower, and the dried cast film was peeled off from the belt by a stripping roller. The flow film was peeled off 120 seconds after it was formed. The solvent content of the casting film at the stripping position was 100% by mass. The stripping was performed with a tension of 150 N / m. This tension is the force per 1 m of width of the casting film. The formed TAC film was guided to a roller dryer and dried while being conveyed in a state where tension was applied in the longitudinal direction by a plurality of rollers. The tension applied in the longitudinal direction was 100 N / m. This tension is the force per 1 m of width of the TAC film. The roller dryer has a first zone on the upstream side and a second zone on the downstream side, and the first zone is set to 80 ° C. and the second zone is set to 120 ° C. The TAC film was transported in the first zone for 5 minutes and in the second zone for 10 minutes. The solvent content of the TAC film wound around the core by the winder was 0.3% by mass. The thickness of the produced TAC film was 130 μm.

One surface 14a of the TAC film obtained above was saponified by the intermediate layer forming apparatus 16 described above, and then an anti-fog film material 18 was obtained. The thickness of the saponified intermediate layer 12 is shown in the “Intermediate layer thickness” column of Table 1.

[Example 1] to [Example 11]
The anti-fog film 10 was manufactured using the resin layer forming apparatus 44. The anti-fog film material 18 prepared according to the production example was used. The types of the coating composition 41, which is the material of the resin layer 13, are as follows. The type, molecular weight, and thickness of the resin layer 13 of the coating composition 41 are shown in the “Coating composition” column, the “Molecular weight” column, and the “Resin layer thickness” column of Table 1, respectively.

Composition for coating Resin component 15 parts by mass Solvent (water) 95 parts by mass

The resin component 1 is as follows. PVP (Pittscol K-50) is polyvinylpyrrolidone (Pittscol K-50, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), and a 5% aqueous solution is prepared from the powder and used. The molecular weight is a weight average molecular weight which is a measured value of capillary viscosity, and is described as "PVP (Pittscol K-50)" in Table 1. The copolymer of vinylpyrrolidone and vinyl acetate is a poly (1-vinylpyrrolidone-vinyl acetate) copolymer manufactured by Tokyo Kasei Kogyo Co., Ltd. (ratio is 1-vinylpyrrolidone: vinyl acetate is 7: 3), and the molecular weight is , The number average molecular weight by GPC, which is described as "P (VP-co-AC)" in Table 1. HEC is hydroxyethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.), and a 5% aqueous solution is prepared from the powder (aqueous solution). The molecular weight is a number average molecular weight by GPC and is described as "HEC" in Table 1. CMC is carboxymethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.), has a degree of etherification of 35%, and has a molecular weight of a number average molecular weight by GPC, which is described as "CMC" in Table 1. The polyacrylamide resin is Polystron 117 manufactured by Arakawa Chemical Industry Co., Ltd., and the molecular weight is the number average molecular weight by GPC, which is described as "polyacrylamide resin" in Table 1.

Moreover, as Example 11, the following coating composition was used. The citric acid aqueous solution is a 5% by mass aqueous solution of citric acid (manufactured by Tokyo Chemical Industry Co., Ltd.). This coating composition is described as "CMC and citric acid" in the "Coating composition" column of Table 1.

Composition for coating 1.2 parts by mass of carboxymethyl cellulose Solvent (water) 58.8 parts by mass 40 parts by mass of aqueous citric acid solution

[evaluation]
The obtained anti-fog film 10 was evaluated. The obtained anti-fog film 10 was cut to obtain a sheet having a size of 10 cm in length and 10 cm in width. The methods and criteria for each evaluation are as follows. The results of each evaluation are shown in Table 1.

1. 1. Anti-fog property The above sheet was placed at a position 15 cm above the water surface of water at 45 ° C. so that the resin layer 13 was parallel to the water surface and exposed, and visually observed for 30 minutes. The evaluation criteria are as follows. A or B is a pass and C is a fail. The evaluation results are shown in the "Anti-fog property" column of Table 1.
A: No cloudiness occurs.
B: Temporarily cloudy, but disappeared.
C: Cloudiness occurs and does not disappear even after 30 minutes.

2. Durability of anti-fog performance After applying steam at about 100 ° C from a hand steamer (Sure Hand Steamer, manufactured by Ishizaki Electric Shure Hand Co., Ltd.) to the resin layer 13 of the above sheet for 30 minutes, leave it for 10 minutes. And dried. Exhaled air was sprayed on the resin layer 13 of the dried sheet for 10 seconds so as to be substantially perpendicular to the resin layer 13. The evaluation criteria are as follows. A or B is a pass and C is a fail. The evaluation results are shown in the "Durability of anti-fog performance" column in Table 1.
A: No cloudiness occurs.
B: Temporarily cloudy, but disappeared instantly.
C: It became cloudy clearly and did not disappear for more than 20 seconds.

3. 3. Freezing anti-fog property A glass 60 with an anti-fog film attached was used. As the flat glass 62, a float glass (soda-lime glass) having a thickness of 5 mm and a square of 10 cm was used. The above sheet cut to the same size as the flat glass 62 was attached with an acrylic adhesive. The anti-fog film-attached glass 60 was cooled in a freezer at −20 ° C. for at least 1 hour, that is, 1 hour or more. Then, in an environment of 25 ° C. and a relative humidity of 50%, the anti-fog film-attached glass 60 was taken out, and the time until it became fogged was measured. The evaluation criteria are as follows. A or B is a pass and C is a fail. Each evaluation result is shown in the "freezing anti-fog property" column of Table 1.
A: It did not become cloudy even after 3 minutes or more.
B: It became cloudy within 1.5 to 3 minutes.
C: It became cloudy within 1.5 minutes.

[Comparative Example 1] to [Comparative Example 3]
In Comparative Examples 1 to 3, anti-fog films were produced in the same manner as in Examples except that the resin layer was changed. In Comparative Example 1, the resin layer 13 was not formed. Therefore, the anti-fog film of Comparative Example 1 is composed of the film base material 11 and the intermediate layer 12. In Comparative Example 2, as the resin layer 13, the resin component of the coating composition used in Examples was PVP (Pitzcol K-17). PVP (Pittscol K-17) is polyvinylpyrrolidone (Pittscol K-17, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), and the molecular weight is the weight average molecular weight measured by capillary viscosity. Call K-17) ”. Further, in Comparative Example 3, the same coating composition as in Example was used as the resin layer 13, and the resin component was PVP (Pittscol K-50). Table 1 shows "PVP (Pitzcall K-50)". Details of PVP (Pitzcall K-50) are as described in the Examples. In Comparative Example 3, the intermediate layer 12 was not formed. Therefore, the anti-fog film of Comparative Example 3 is composed of the film base material 11 and the resin layer 13.

Comparative Examples 1 to 3 were also evaluated in the same manner as in Examples. The results of each evaluation are shown in Table 1. Since the resin layer 13 is not formed in Comparative Example 1, "None" is described in the column of "Composition for coating" in Table 1, and each of "Molecular weight" and "Durability of antifogging performance" is described. "-" Is written in the column. Further, since Comparative Example 3 did not form the intermediate layer 12, “0” was described in the “Intermediate layer thickness” column of Table 1.

10 Anti-fog film 11 Film base material 11a One surface 11b The other surface 12 Intermediate layer 12a One surface 12b The other surface 13 Resin layer 14 TAC film 14a One surface 14b The other surface 16 Intermediate layer forming device 18 Anti-fog film Material 20 Sender 22 Saponification unit 24 Drying device 26 Winding machine 28 Winding core 30 Coating device 30a Outlet 32 Infrared heater 34 Cleaning device 36 Roller 38 Saponifying liquid 40 Coating film 41 Coating composition 42 Winding core 44 Resin layer forming device 46 Sender 48 Resin layer forming unit 49 Drying device 50 Coating device 50a Outlet 51 Winding machine 52 Infrared heater 54 Roller 56 Coating film 58 Winding core 60 Anti-fog film affixed glass 62 Plate glass 64 Adhesive layer T10 Anti-fog film thickness T12 Intermediate layer thickness T13 Resin layer thickness

Claims (6)

A film substrate formed of cellulose acylate having an acyl group substitution degree in the range of 2.00 or more and 2.97 or less, and
A first layer formed of cellulose acylate or cellulose having a lower degree of acyl group substitution than the film substrate and provided on one surface of the film substrate.
It contains a resin component having a molecular weight of 30,000 or more, and has a second layer provided on a surface opposite to the surface in contact with the film substrate among the surfaces of the first layer.
The resin component has any one of a hydroxy group, an amide structure, and a pyrrolidone structure.
The first layer has a thickness in the range of 0.5 μm or more and 20 μm or less.
The second layer state, and are within the range of 1μm or more 20μm or less in thickness,
The resin component having a hydroxy group is a cellulose derivative having the hydroxy group and having a group that ether-bonds with cellulose.
The resin component having the amide structure is a polyamide or a polyacrylamide.
An anti-fog film in which the resin component having a pyrrolidone structure is a polymer having a vinyl pyrrolidone structure. The anti-fog film according to claim 1, wherein the resin component having a hydroxy group is hydroxyethyl cellulose or carboxymethyl cellulose. The anti-fog film according to claim 1 , wherein the resin component having a hydroxy group is carboxymethyl cellulose. The anti-fog film according to claim 1, wherein the resin component having the amide structure is polyacrylamides. The antifogging film according to claim 1 , wherein the resin component having a pyrrolidone structure is a polymer obtained by copolymerizing a vinylpyrrolidone compound with vinyl acetate and / or an acrylic derivative. The claim that the resin component having a pyrrolidone structure is the polymer obtained by copolymerizing the vinylpyrrolidone compound and the vinyl acetate with the vinylpyrrolidone compound: the vinyl acetate in a mass portion of 7: 3. The anti-fog film according to 5.

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