JP7087176B1 - Anti-fog layer and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anti-fog layer using an aqueous solvent and having excellent anti-fog property. SOLUTION: The antifogging layer contains organic fine particles (A) and has a surface roughness Ra of 5 nm or more and 200 nm or less. [Selection diagram] Fig. 1

Description

The present invention relates to an anti-fog layer and its use.

Patent Document 1 describes an antifogging thin film formed from a solution in which a metal alkoxide-based compound, oxide fine particles having a low equilibrium water vapor pressure, and titania fine particles in the form of photocatalytically active anatase crystals are dispersed. ..

Patent Document 2 describes a water-absorbent anti-fog member having a fine concavo-convex structure whose surface is smaller than the wavelength λ of light to be transmitted.

Patent Document 3 describes a composition for forming an anti-fog layer containing a copolymer containing a specific structural unit and a hydrolyzate.

Patent Document 4 describes a coating film containing a metal oxide and polymer particles and having a ten-point average roughness of 5 nm or more and 300 nm or less.

Japanese Unexamined Patent Publication No. 10-10137 Japanese Unexamined Patent Publication No. 2004-45671 Japanese Unexamined Patent Publication No. 2018-2865 Japanese Patent No. 6438822

The generation of VOCs causes air pollution. Therefore, in 2004, the revised Air Pollution Control Law was issued in Japan, and it is required to reduce the amount of VOCs generated. The paint and ink industry uses large amounts of organic solvents to reduce viscosity during coating operations. Furthermore, of the 700,000 tons of VOCs generated in Japan, the paint industry accounts for about 40% and the ink industry accounts for about 5% of VOCs. As described above, VOC measures are an issue in the paint industry and the ink industry.

In the paint coating work, various measures are taken to reduce the amount of organic solvent used. For example, the conversion from organic solvent-based paints to water-based paints.

Solvent-based paints are currently used for anti-fog paints for headlamps. However, in order to reduce the amount of organic solvent used, it is necessary to switch to water-based paints. However, anti-fog paints for headlamps are required to have heat resistance. Until now, no water-based anti-fog paint could meet the heat resistance standard.

Further, in the method of forming a film containing a metal alkoxide-based compound to form an anti-fog thin film as in Patent Document 1, it is necessary to bake at about 650 ° C. after coating on a glass substrate. Therefore, this method cannot be used for plastic applications.

Although Patent Document 2 describes an anti-fog member having a fine concavo-convex structure on its surface as described above, it is actually difficult to fabricate the concavo-convex structure on the surface with a water-absorbent anti-fog film. ..

It is difficult to maintain the anti-fog property of the anti-fog layer forming composition described in Patent Document 3 after the heat resistance test. Further, since an organic solvent is required in the production of the copolymer in the anti-fog layer, it is difficult to eliminate the organic solvent and use a water-based paint.

It is difficult for the coating film described in Patent Document 4 to maintain anti-fog properties after a heat resistance test.

One aspect of the present invention has been made in view of such circumstances, and an object of the present invention is to provide an anti-fog layer that can be formed by using an aqueous solvent and has excellent anti-fog properties.

In order to solve the above problems, the anti-fog layer according to one aspect of the present invention contains organic fine particles (A) and has a surface roughness Ra of 5 nm or more and 200 nm or less.

According to one aspect of the present invention, it is possible to provide an anti-fog layer that uses an aqueous solvent and has excellent anti-fog properties.

FIG. 3 is an AFM (Atomic Force Microscopy) diagram of the antifogging layer of Example 32.

Hereinafter, one embodiment of the present invention will be described in detail.

In the present specification, "(meth) acrylic acid" means either or both of "acrylic acid" and "methacrylic acid", and "(meth) acrylate copolymer" means "(meth)". It means "a resin containing acrylic acid and its derivatives as a main constituent unit". Here, "(meth) acrylic acid" and "(meth) acrylic acid derivative" are collectively referred to as "(meth) acrylic acid-based monomer", and "(meth) acrylic acid derivative" includes (meth). ) Acrylate ((meth) acrylic acid ester) and (meth) acrylamide are exemplified.

<Anti-fog layer>
The anti-fog layer according to one embodiment of the present invention contains organic fine particles (A) and has a surface roughness Ra of 5 nm or more and 200 nm or less. The anti-fog layer contains organic fine particles (A), preferably contains a curing agent (B) and a resin (C), and may contain other components. According to one aspect of the present invention, since water can be used to prepare an anti-fog layer having excellent anti-fog properties, the amount of organic solvent used can be reduced. As a result, the cause of air pollution and the generation of VOC can be suppressed. Therefore, according to one aspect of the present invention, it is possible to reduce the adverse effect on the air environment, and thus it is possible to contribute to the goal 11 of the Sustainable Development Goals (SDGs) led by the United Nations, "Creating a town where people can continue to live". It will be possible.

(Surface roughness Ra)
The surface roughness Ra of the anti-fog layer is 5 nm or more, and more preferably 10 nm or more. When the surface roughness Ra of the anti-fog layer is coarser at 5 nm or more, the specific surface area of the anti-fog layer surface can be increased, thereby enhancing the anti-fog property of the anti-fog layer. In other words, when the surface roughness Ra of the anti-fog layer is less than 5 nm, the uneven shape formed on the surface of the anti-fog layer becomes small, and as a result, the surface area caused by the fine unevenness becomes small, so that the anti-fog layer becomes small. The amount of water that penetrates into is reduced. Therefore, the anti-fog property of the anti-fog layer is lowered. The surface roughness Ra of the anti-fog layer is 200 nm or less, preferably 150 nm or less, more preferably 100 nm or less, further preferably 70 nm or less, and further preferably 50 nm or less. Most preferred. By making the surface roughness Ra of the anti-fog layer finer at 200 nm or less, it is possible to prevent the light transmittance of the anti-fog layer from being lowered due to the scattering of visible light on the unevenness existing on the surface of the anti-fog layer. can. Therefore, the light transmission of the anti-fog layer can be enhanced. That is, the anti-fog layer can have both high anti-fog property and high light transmission property when the surface roughness Ra is 5 nm or more and 200 nm or less.

As the "surface roughness Ra" of the anti-fog layer, the "arithmetic mean roughness Ra" defined in JIS-B-0601: 2013 is adopted. A surface roughness measuring instrument [manufactured by Kosaka Laboratory Co., Ltd., model name Surfcorer SE500] was used, and the surface roughness Ra was determined under the conditions of a scanning range of 4 mm and a scanning speed of 0.2 mm / s.

(Water contact angle)
The contact angle of the anti-fog layer with water is preferably 10 ° or less, and more preferably 5 ° or less. When the anti-fog layer has a water contact angle of 10 ° or less, the anti-fog layer can have high anti-fog properties. The contact angle of the anti-fog layer with water may be evaluated using a test piece left at room temperature of 23 ° C. and relative humidity of 50%.

The anti-fog layer mainly contains a solid content containing a material contained in the composition for producing the anti-fog layer and a reaction product thereof. The "solid content" contains the organic fine particles (A) and the curing agent (B), and preferably contains the resin (C). The organic fine particles (A) and the resin (C), which are solids in the anti-fog layer, and the curing agent (B) can react with each other to form a reactant in the anti-fog layer. In addition to the organic fine particles (A), the curing agent (B), and the resin (C), the anti-fog layer includes inorganic particles, an absorbent, and others described later, as long as the effects of the present invention are not impaired. May contain the components of.

(Organic fine particles (A))
The organic fine particles (A) are fine particles of a resin having a polar group, and can be contained in the anti-fog layer while maintaining the shape of the particles. By including the organic fine particles (A) in the anti-fog layer while maintaining the shape of the particles, it is possible to impart a desired surface roughness Ra to the anti-fog layer. That is, the organic fine particles (A) can bring about a surface roughness Ra of 5 nm or more and 200 nm or less of the anti-fog layer. The content of the organic fine particles (A) in the anti-fog layer can be 58% by mass or more, preferably 65% by mass or more, preferably 75% by mass or more, assuming that the total solid content in the anti-fog layer is 100% by mass. Is more preferable, and 80% by mass or more is further preferable. When the content of the organic fine particles (A) in the anti-fog layer is higher in the range of 58 to 99% by mass, the surface roughness Ra of the anti-fog layer can be made larger, whereby anti-fog can be obtained. It can enhance the sex. Further, when the content of the organic fine particles (A) in the anti-fog layer is less than 99% by mass, the film strength of the anti-fog layer can be further increased. Therefore, when the amount is less than 99% by mass, the number of components that bind the organic fine particles (A) to each other can be increased, and the anti-fog layer can be suitably formed. The content of the organic fine particles (A) in the anti-fog layer means the content as a solid content that does not substantially contain a dispersion medium.

The organic fine particles (A) are selected based on the particle size D50, the average SP value of the monomers contained in the resin of the organic fine particles (A) as a constituent unit, and the glass transition temperature (Tg) of the resin. It is good to do it.

(Particle diameter (D50))
The surface roughness Ra of the anti-fog layer of the organic fine particles (A) can be adjusted by the particle size thereof. Here, the particle diameter D50 of the organic fine particles (A) is a particle diameter corresponding to a cumulative total of 50% on a volume basis, and the particle diameter D50 is sometimes referred to as a medium particle diameter or a median diameter. The volume-based particle size D50 may be obtained by a laser diffraction method using a dynamic light scattering type particle size distribution measuring device or the like.

The particle size D50 of the organic fine particles (A) is preferably in the range of 5 nm or more and 200 nm or less, more preferably in the range of 10 nm or more and 150 nm or less, and more preferably in the range of 15 nm or more and 100 nm or less. Is even more preferable. The surface roughness Ra of the anti-fog layer can be further increased due to the unevenness caused by the organic fine particles (A) having a particle size D50 in the range of 5 nm or more and 200 nm. That is, the surface roughness Ra of the anti-fog layer can be set within the range of 5 nm or more and 200 nm or less by the organic fine particles (A). That is, the organic fine particles (A) can bring about a surface roughness Ra of 5 nm or more and 200 nm or less of the anti-fog layer. Therefore, the anti-fog property of the anti-fog layer can be enhanced. Further, by using the organic fine particles (A) having a particle size D50 smaller in the range of 5 nm or more and 200 nm or less, the light transmittance of the anti-fog layer can be further enhanced.

数式（１）中、δは溶解度パラメータ（ＳＰ値）であり、Σ_ｉΔｅｉは、単量体が有するモル蒸発エネルギー（ｃａｌ／ｍｏｌ）であり、Σ_ｉΔｖｉは単量体のモル体積（ｃｍ^３／ｍｏｌ）である。なお、上記数式（１）から求められる溶解度パラメータの単位は（ｃａｌ／ｃｍ^３）^１／２であり、本明細書では、２．０４５５×（ｃａｌ／ｃｍ^３）^１／２＝（Ｊ／ｃｍ^３）^１／２＝ＭＰａ^１／２であるとして、ＳＰ値の単位にＭＰａ^１／２を採用する。有機微粒子（Ａ）が有する親水性は、有機微粒子（Ａ）に構成単位として含まれる単量体のＳＰ値の平均値を指標として確認するとよい。 (SP value)
The average value of the SP values of the monomers contained in the resin constituting the organic fine particles (A) as a constituent unit is the mass ratio (in which each monomer is contained in the resin as a constituent unit) for each SP value of the monomer. It is calculated as the sum of the values obtained by multiplying by mass%). The SP value of each monomer is calculated by the following formula (1) based on the Fedors calculation method (see "Polymer Engineering and Science", Vol. 14, No. 2 (1974), pp. 148 to 154). be able to.

In the formula (1), δ is the solubility parameter (SP value), Σ _i Δei is the molar evaporation energy (cal / mol) of the monomer, and Σ _i Δvi is the molar volume (cm) of the monomer. ³ / mol). The unit of the solubility parameter obtained from the above formula (1) is (cal / cm ³ ) ^1/2 , and in the present specification, 2.0455 × (cal / cm ³ ) ^1/2 = (J / cm). ³ ) Assuming that ^1/2 = MPa ^1/2 , MPa ^1/2 is adopted as the unit of SP value. The hydrophilicity of the organic fine particles (A) may be confirmed by using the average value of the SP values of the monomers contained in the organic fine particles (A) as a constituent unit as an index.

The average SP value of each monomer contained in the organic fine particles (A) as a constituent unit can be 21 MPa ^1/2 or more, preferably 24 MPa ^1/2 or more, and 26 MPa ^1/2 or more. It is preferably 27 MPa ^1/2 or more, and more preferably 27 MPa 1/2 or more. Further, the SP value of the organic fine particles (A) is preferably 32 MPa ^1/2 or less. The average value of the SP values of the monomers (sometimes referred to as the SP average value) is 21 MPa ¹ from the viewpoint of making the organic fine particles (A) closer to the SP value (47.9) of water in order to increase the hydrophilicity. A higher value is preferable with ^{/ 2} as the lower limit. Further, the SP value of the monomer obtained from the formula (1) is not limited as long as it is close to the SP value of water (47.9 MPa ^1/2 ), but may be 32 MPa ^1/2 or less.

The monomer contained as a constituent unit in the resin may be a (meth) acrylic monomer, and the (meth) acrylic monomer may be, for example, a (meth) acrylamide-based monomer or a (meth) acrylate. Examples thereof include a system monomer and a (meth) acrylic acid system monomer, and other monomers described later may be contained. The (meth) acrylic monomer such as the (meth) acrylamide-based monomer and the (meth) acrylate-based monomer may have a crosslinkable functional group, and the crosslinkable functional group is used. , A crosslinkable functional group other than an unsaturated double-bonding group such as a vinyl group and a (meth) acryloyl group that contributes because the monomer is contained as a constituent unit of the resin constituting the organic fine particles (A). means.

The (meth) acrylamide-based monomer is a preferable monomer as a monomer having a high SP value. That is, when the (meth) acrylate copolymer contains a structural unit derived from the (meth) acrylamide-based monomer, the SP value of the resin can be increased and the hydrophilicity of the organic fine particles (A) can be increased. Can be done. Examples of the (meth) acrylamide-based monomer include acrylamide, acryloylmorpholine , methacrylamide, dialkyl (meth) acrylamide such as dimethylacrylamide, and monoalkyl (meth) acrylamide such as isopropylacrylamide. The structural unit derived from the (meth) acrylamide-based monomer is the total of the structural units derived from the monomer contained in the (meth) acrylate copolymer from the viewpoint of enhancing the hydrophilicity of the organic fine particles (A). As 100% by mass, it is preferably contained in an amount of 5 to 100% by mass, and more preferably 50 to 95% by mass. The (meth) acrylamide-based monomer may have a crosslinkable functional group like the (meth) acrylate-based monomer described later.

Examples of the crosslinkable functional group of the (meth) acrylamide-based monomer include N-methylol group, N-alkoxymethylol group, N-methylol ether group and the like, and have such a crosslinkable functional group (meth). Examples of the meta) acrylamide-based monomer include N-methylolacrylamide and N-methylolmethacrylate.

Examples of the (meth) acrylate-based monomer include a (meth) acrylate-based monomer having no crosslinkable functional group and a (meth) acrylate-based monomer having a crosslinkable functional group. Be done. The (meth) acrylate-based monomer having no crosslinkable functional group has, for example, an alkyl (meth) acrylate such as butyl methacrylate and ethyl methacrylate; and a dialkylamino group such as dimethylaminoethyl acrylate ( Examples thereof include (meth) acrylate-based monomers having a structure derived from (poly) alkylene glycol such as meth) acrylate;, methoxyethyl acrylate, and methoxydiethylene glycol acrylate. The structural unit derived from the (meth) acrylate-based monomer having no crosslinkable functional group in the fine particle resin is, for example, within the range in which the average SP value of the monomer is 21 MPa ^1/2 or more. It may be included in.

Examples of the crosslinkable functional group contained in the (meth) acrylate-based monomer include a crosslinkable functional group such as a hydroxyl group, a carboxyl group, a mercapto group, a phenol group, an amino group, a silanol group and an alkoxysilyl group. Examples of the (meth) acrylate-based monomer having these crosslinkable functional groups include 2-hydroxyethyl (meth) acrylate.

A (meth) acrylate-based monomer having a crosslinkable functional group other than an unsaturated double bond group such as a vinyl group and a (meth) acryloyl group is contained in the (meth) acrylate copolymer as a constituent unit. Then, the crosslinkable functional group can react with, for example, the curing agent (B) described later, inorganic particles, or the like. Further, the structural units derived from the (meth) acrylamide-based monomer having an N-methylol group, an N-alkoxymethylol group, and an N-methylol ether group are contained in the organic fine particles (A) by a dehydration condensation reaction and a dealcohol condensation reaction. It is expected that the surface roughness Ra of the antifogging layer can be easily maintained by cross-linking with and stabilizing the shape of the organic fine particles (A), which is preferable. The (meth) acrylic monomer having a crosslinkable functional group is not limited, but the total of the structural units derived from the monomers contained in the (meth) acrylate copolymer is 100% by mass. % Is preferably contained in an amount of 1 to 100% by mass, more preferably 5 to 90% by mass.

Examples of the (meth) acrylic acid-based monomer include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, malein and the like. The (meth) acrylic acid-based monomer may preferably be acrylic acid or methacrylic acid. These (meth) acrylic acid-based monomers can also be, for example, monomers that can react with the curing agent (B) described later in that they have a carboxyl group as a crosslinkable functional group.

Examples of other monomers include monomers such as acrylonitrile and methacrylonitrile, and vinyl-based monomers such as vinyl acetate, styrene, N-vinylpyrrolidone, and vinylmethyloxazolidinone, and examples thereof include vinyl. Methyloxazolidinone can be a monomer having an oxazolidinone group as a crosslinkable functional group.

Table 1 below exemplifies typical monomers that can be contained as a constituent unit in the resin of the organic fine particles (A) and their SP values. From the SP values of the monomers exemplified in Table 1, it can be confirmed that the (meth) acrylamide-based monomer is preferable in that it has a high SP value.

The organic fine particles (A) are typically derived from the above-mentioned (meth) acrylamide-based monomer, (meth) acrylate-based monomer, and (meth) acrylic acid-based monomer as the main structural unit. It can be a fine particle of a (meth) acrylate copolymer containing a constituent unit. The (meth) acrylate copolymer can suitably impart hydrophilicity to the organic fine particles (A) by containing a structural unit derived from a monomer having a high SP value.

(Glass transition temperature of organic fine particles (A))
The resin constituting the organic fine particles (A) may have a glass transition temperature of 60 ° C. or higher, better at 80 ° C. or higher, preferably 90 ° C. or higher, and more preferably 100 ° C. or higher. It is more preferably 110 ° C. or higher, and most preferably 120 ° C. or higher. When the glass transition temperature of the organic fine particles (A) is higher at 60 ° C. or higher, the heat resistance of the anti-fog layer can be enhanced. This means that the surface roughness Ra of the anti-fog layer can be maintained even at a higher temperature by further enhancing the heat resistance of the organic fine particles (A) itself, and thereby the anti-fog brought about by the surface roughness. It is expected that this is because it is possible to prevent deterioration of sex. The resin constituting the organic fine particles (A) is not limited, but may have a glass transition temperature of 250 ° C. or lower.

The glass transition temperature of the organic fine particles (A) can be determined from the DSC curve evaluated according to JIS-K-7122: 2012 by the differential scanning calorimetry (DSC) analysis method. The evaluation conditions such as the temperature scanning range for obtaining the DSC curve and the temperature scanning speed are described in detail in the examples, so refer to them.

Further, the glass transition temperature of the organic fine particles (A) may be estimated as an average value of the glass transition temperatures of the homopolymers of each monomer contained in the organic fine particles (A) as a constituent unit. The glass transition temperature of the organic fine particles (A) is obtained by multiplying each monomer by the glass transition temperature of the homopolymer of the monomer and the mass ratio (% by mass) of each monomer contained in the resin as a constituent unit. It is estimated as the sum of the values obtained. Here, the glass transition temperature of the homopolymer may refer to the value calculated by the Fox formula described in the Polymer Handbook [Polymer Hand Book (J. Brandrup, Interscience 1989)], for example, the number average molecular weight is 5000. The glass transition temperature of the homopolymer of about 100,000 may be obtained from the DSC curve according to JIS-K-7122: 2012 in the same manner as the above-mentioned method for measuring the glass transition temperature of the organic fine particles (A). The organic fine particles (A) can increase the glass transition temperature of the organic fine particles (A) by containing a large amount of a monomer having a higher glass transition temperature of the homopolymer as a constituent unit, whereby the antifogging layer can be increased. The heat resistance of the glass can be increased. From the viewpoint of increasing the glass transition temperature of the organic fine particles (A), the glass transition temperature of the monomer homopolymer contained in the organic fine particles (A) as a constituent unit can be 60 ° C. or higher, and is 80 ° C. or higher. It is better to have a temperature of 90 ° C. or higher, more preferably 100 ° C. or higher, further preferably 110 ° C. or higher, and most preferably 120 ° C. or higher. Further, although not limited, the glass transition temperature of the monomer homopolymer contained in the organic fine particles (A) as a constituent unit may be 250 ° C. or lower. Examples of the (meth) acrylamide-based monomer having a high glass transition temperature of the homopolymer include acrylamide (tg of homopolymer: 153 ° C), acryloylmorpholin (Tg of homopolymer: 145 ° C) and the like. From the viewpoint of increasing the glass transition temperature of the organic fine particles (A), the organic fine particles (A) refer to the organic fine particles (A) as a structural unit derived from a monomer having a glass transition temperature of 60 ° C. or higher in the homopolymer. Assuming that the constituent copolymer is 100% by mass, it is preferably contained in an amount of 60% by mass or more, and more preferably 80% by mass or more. Further, although not limited, the organic fine particles (A) contain 60% by mass or more of structural units derived from a monomer having a high glass transition temperature in the homopolymer and being 80 ° C. or higher, and the glass in the homopolymer. The glass of the organic fine particles (A) is made of 40% by mass or less, with 100% by mass of the copolymer constituting the organic fine particles (A) as the structural unit derived from the monomer having a transition temperature lower than 80 ° C. The transition temperature may be increased. For example, the organic fine particles (A) are included as a structural unit derived from a monomer having a polyethylene glycol chain such as methoxypolyethylene glycol methacrylate from the viewpoint of enhancing the dispersion stability of the organic fine particles (A) itself in an aqueous system. It is preferable to have. However, the structural unit derived from a monomer such as methoxypolyethylene glycol methacrylate has a low glass transition temperature of the homopolymer. Therefore, it may also contribute to lowering the heat resistance of the organic fine particles (A), and as a result, there is a tendency to lower the anti-fog property after being exposed to heat. From the viewpoint of preventing the organic fine particles (A) from being lowered due to antifogging heat, the constituent unit having a low glass transition temperature of the homopolymer is 100% by mass based on the total amount of the constituent units contained in the organic fine particles (A). , 40% by mass or less is preferable. The glass transition temperature of the constituent unit of the homopolymer having a low glass transition temperature can be −40 ° C. or lower, preferably 0 ° C. or lower, more preferably 40 ° C. or lower, and lower than 80 ° C. Is the most preferable.

The organic fine particles (A) can be obtained from Takamatsu Oil & Fat Co., Ltd. as, for example, a powder or a dispersion liquid.

(Glass transition temperature (Tg) of anti-fog layer)
The glass transition temperature (Tg) of the anti-fog layer according to one aspect of the present invention can be 60 ° C. or higher, more preferably 80 ° C. or higher, preferably 90 ° C. or higher, and preferably 100 ° C. or higher. Is more preferable, 110 ° C. or higher is further preferable, and 120 ° C. or higher is most preferable. This makes it possible to increase the heat resistance of the anti-fog layer. In order to increase the glass transition temperature (Tg) of the anti-fog layer, it is preferable to select the organic fine particles (A) having the above-mentioned glass transition temperature. Further, the glass transition temperature of the anti-fog layer can be increased by containing the curing agent (B) and / or the resin (C) described below in the anti-fog layer.

(Curing agent (B))
The anti-fog layer preferably contains a curing agent (B). This makes it possible to obtain an anti-fog layer in which the individual particles constituting the organic fine particles (A) are fixed to each other via the curing agent (B) in the layer. The curing agent (B) may contain a compound having at least one crosslinkable functional group. The anti-fog layer may also be a layer formed by a cross-linking reaction product of the compound having a cross-linking functional group contained in the curing agent (B) and the organic fine particles (A). The curing agent (B) may be a compound that undergoes a cross-linking polymerization reaction by itself, but it undergoes a cross-linking reaction with the cross-linking functional group of the (meth) acrylate-based monomer that is a constituent unit of the organic fine particles (A). It is preferable that the compound has a functional group capable of cross-linking. The compound contained in the curing agent (B) preferably has at least one, preferably two or more crosslinkable functional groups in its chemical structure. The curing agent (B) may be any of a monomeric compound, an oligomer, and a polymer as long as it has at least one or more crosslinkable functional groups.

The content of the curing agent (B) is preferably in the range of 1% by mass or more and 30% by mass or less in terms of solid content, with the total solid content of the anti-fog layer being 100% by mass. Within this range, the greater the content of the curing agent (B), the higher the film strength of the anti-fog layer. Further, in the range of 1% by mass or more and 30% by mass or less, the smaller the amount, the higher the anti-fog property can be imparted to the anti-fog layer.

The functional group capable of cross-linking with the cross-linking functional group of the above-mentioned organic fine particles (A) contained in the compound contained in the curing agent (B) is a cross-linking functional group because it is a functional group that cross-links with each other. It is synonymous. Examples of the crosslinkable functional group contained in the curing agent (B) include a carbodiimide group, an epoxy group, an isocyanate group, a blocked isocyanate group, an oxazoline group, a hydrazide group, and an aziridine group. These crosslinkable functional groups include an N-methylol group, an N-alkoxymethylol group, an N-methylol ether group, and a hydroxyl group, a silanol group, and an alkoxysilyl group, which can be possessed by the above-mentioned (meth) acrylate-based monomer. It can suitably react with a crosslinkable functional group such as a carboxyl group, a mercapto group, a phenol group, and an amino group.

The compound having such a crosslinkable functional group is not limited, but is preferably a water-soluble compound that dissolves in an aqueous system or a compound having an aqueous dispersibility that is dispersed in an aqueous system. That is, the curing agent (B) can be obtained as an aqueous solution, an aqueous dispersion, or an emulsion and contained in a composition for forming an anti-fog layer. The curing agent (B) may contain an organic solvent as long as the effect of the present invention is not impaired.

Examples of the curing agent (B) include, for example, carbodilite (registered trademark) (manufactured by Nisshinbo Chemical Co., Ltd.), carbodiista (registered trademark) (manufactured by Teijin Co., Ltd.), N, N'-as a curing agent having a carbodiimide group. Dicyclohexylcarbodiimide (available from Tokyo Kasei Kogyo Co., Ltd.), N, N'-diisopropylcarbodiimide (available from Fujifilm Wako Junyaku Co., Ltd.), 1- [3- (dimethylamino) propyl] -3-ethylcarbodiimide (available from Fujifilm Wako Junyaku Co., Ltd.) (Available from Fujifilm Wako Junyaku Co., Ltd.), 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride (available from Fujifilm Wako Junyaku Co., Ltd.), Bis (2,6-diisopropylphenyl) carbodiimide (Available from Kawaguchi Chemical Industry Co., Ltd.) and the like. Examples of the curing agent having an epoxy group include Denacol (registered trademark) (manufactured by Nagase ChemteX Corporation), water-based epoxy resin jER (registered trademark) series (manufactured by Mitsubishi Chemical Co., Ltd.), and ADEKA REGIN (registered trademark) EM series (manufactured by Nagase ChemteX Corporation). ADEKA CORPORATION) and the like. Examples of the curing agent having a blocked isocyanate group include Duranate (registered trademark) (manufactured by Asahi Kasei Corporation) and Coronate (registered trademark) series (manufactured by Tosoh Corporation). Examples of the curing agent having an oxazoline group include Epocross (registered trademark) (manufactured by Nippon Shokubai Co., Ltd.), poly (2-ethyl-2-oxazoline) (available from Fujifilm Wako Pure Chemical Industries, Ltd.) and the like. .. Examples of the curing agent having a hydrazide group include adipic acid dihydrazide (available from Tokyo Kasei Co., Ltd.), sebacic acid dihydrazide, dodecandiohydrazide, isophthalic acid dihydrazide, salicylic acid hydrazide (all available from Otsuka Chemical Co., Ltd.), etc. Can be mentioned. As a curing agent having an aziridine group, Chemitite (registered trademark) (manufactured by Nippon Shokubai Co., Ltd.), trimethylolpropane tris [3- (2-methylaziridine-1-yl) propionate] (available from Nippon Daikei Energy Co., Ltd.) And so on.

(Resin (C))
The anti-fog layer preferably contains a resin (C) in addition to the above-mentioned organic fine particles (A) and curing agent (B). Since the anti-fog layer contains the resin (C), the resin (C) and the curing agent (B) can be reacted to form a stronger film, and the glass transition temperature of the anti-fog layer itself can be formed. Can be enhanced. Further, by containing the resin (C), the adhesion to the substrate can be improved.

That is, the resin (C) may have at least a crosslinkable functional group so as to react with the curing agent (B). Among them, the crosslinkable functional group may be, for example, an acid group such as a carboxyl group, a hydroxyl group, a phenol group, an amino group or the like from the viewpoint of enhancing the water solubility or water dispersibility of the resin (C) itself. It is more preferable to have. Examples of the resin (C) include polyester resin, polycarbonate-based urethane resin, epoxy ester resin, alkyd resin, water-soluble phenol resin, and the like, and the resin (C) is a water-soluble resin, a water-dispersible resin, or a resin. It can be an emulsion. The anti-fog layer can be suitably prepared as an aqueous coating agent by containing the resin (C).

When the resin (C) has an acid group such as a carboxyl group, the acid value of the resin (C) is preferably in the range of 1 to 200 mgKOH / g, and preferably 2 to 60 mgKOH / g. preferable. Thereby, within the range of the acid value, the higher the acid value, the higher the water solubility of the resin (C) and the higher the heat resistance of the anti-fog layer. Further, the higher the acid value, the more the composition described below can be used as an aqueous solvent-based composition. Further, the lower the acid value, the higher the water resistance of the anti-fog layer containing the resin (C).

When the resin (C) has a hydroxyl group, the hydroxyl value of the resin (C) is preferably in the range of 1 to 200 mgKOH / g, and preferably 2 to 120 mgKOH / g. Thereby, within the range of the hydroxyl value, the higher the hydroxyl value, the higher the water solubility of the resin (C) and the higher the heat resistance of the anti-fog layer. Further, the higher the hydroxyl value, the more the composition described below can be used as an aqueous solvent-based composition. Further, the lower the hydroxyl value, the higher the water resistance of the anti-fog layer containing the resin (C).

In addition, when the resin (C) is a resin having a phenol group or an amino group, the water solubility of the resin (C) and the heat resistance of the antifogging layer to be produced are the same as those of the resin (C) having a carboxyl group and a hydroxyl group. , And the amount of phenol group or amino group of the resin (C) may be designed in consideration of the water resistance of the antifogging layer.

The resin (C) preferably has a glass transition temperature of 20 ° C. or higher, more preferably 50 ° C. or higher. Thereby, the heat resistance of the anti-fog layer can be further improved.

The blending ratio of the curing agent (B) and the resin (C) is such that the glass transition temperature of the cured product of the curing agent (B) and the resin (C) is high, so that the type of the curing agent (B) and the resin (C) is high. Depending on the above, for example, an appropriate blending ratio may be determined from the acid value and / or the hydroxyl value.

The anti-fog layer is contained in the anti-fog layer so that the total amount of the curing agent (B) and the resin (C) is 2% by mass or more and 43% by mass or less in terms of the solid content contained in the anti-fog layer. It is preferable that the amount is less than the above range, and the heat resistance of the anti-fog layer can be enhanced. The total content of the curing agent (B) and the resin (C) in the anti-fog layer is preferably 43% by mass or less, more preferably 20% by mass or less in terms of solid content. Further, when the total content of the curing agent (B) and the resin (C) in the anti-fog layer is 2% by mass or more, the film strength of the anti-fog layer can be increased.

The resin (C) can be obtained, for example, as an aqueous solution, an aqueous dispersion, or an emulsion, and can be contained in a composition described later.

Examples of the resin (C) include a pesresin series (manufactured by Takamatsu Oil & Fat Co., Ltd.) and Aronmelt (registered trademark) PES-1000 and 2000 series (manufactured by Toagosei Co., Ltd.) as polyester resins. Further, examples of the aqueous phenol resin include Phenolite (registered trademark) TD-4304 (manufactured by DIC Corporation) and the like. Examples of the polycarbonate-based urethane resin include Hydran (registered trademark) (manufactured by DIC Corporation), an epoxy ester resin, and examples of the alkyd resin include watersol (registered trademark) (manufactured by DIC Corporation).

(Inorganic particles)
The anti-fog layer may contain inorganic particles as other components. The inorganic particles contained in the antifogging layer are preferably, for example, alumina, silica, zirconia, titania, zinc oxide, other metal oxide fine particles, carbon and the like, and alumina sol, colloidal silica, silica sol, zirconia sol, titania sol and other metals. It can be obtained as colloidal particles such as sol of oxide fine particles. The colloidal particles can be acidic sol, alkaline sol, or neutral stabilized sol. The inorganic particles can be crosslinked with the above-mentioned curing agent (B) and / or resin (C), and the inorganic particles can also be crosslinked with each other.

The volume-based particle diameter D50 of the inorganic particles can be 2 nm or more, and is preferably 3 nm or more. This can prevent the surface roughness of the anti-fog layer from being impaired. Further, it is preferable that the particle size D50 of the inorganic particles is 200 nm or less from the viewpoint of imparting high light transmittance to the anti-fog layer.

The content of the inorganic particles is preferably in the range of 0.1% by mass or more and 10.0% by mass or less, with the total amount of solids contained in the anti-fog layer being 100% by mass. When the content of the inorganic particles is 10.0% by mass or less, it is possible to suitably prevent the deterioration of the anti-fog property due to the inorganic particles. Further, when the content of the inorganic particles is 0.1% by mass or more, the anti-fog layer has an effect of imparting high heat resistance as light transmission.

The inorganic particles may be obtained as a powder, a dispersion liquid, or a sol, and may contain an organic solvent such as alcohol as long as the effects of the present invention are not impaired. Examples of such inorganic particles include alumina sol 10A (manufactured by Kawaken Fine Chemical Industries, Ltd.) and Snowtech (registered trademark) series (manufactured by Nissan Chemical Industries, Ltd.) as colloidal silica.

(Other ingredients)
The anti-fog layer may contain an absorbent, a film thickening aid, and an anti-freezing agent as other components.

Examples of the absorbent include mixed layer clay and the like. The mixed layer clay can preferably be an industrially synthesized synthetic clay, and examples thereof include smectite, bentonite, montmorillonite and the like. By adding an absorbent, it is possible to add a function of absorbing water to the anti-fog layer to retain water, and it is possible to improve the anti-fog performance. These mixed layer clays can be contained in the composition described later as a sedimentation inhibitor and / or a viscosity modifier in addition to the absorbent.

The mixed layer clay is not limited, but it is preferable to use, for example, one having a particle size D50 in the major axis of 200 nm or less. The content of the mixed layer clay may be appropriately designed within a range that does not impair the effect of the present invention. For example, the total solid content contained in the anti-fog layer is 100% by mass, and 0.1% by mass or more and 5.0. It is preferably in the range of mass% or less.

Examples of the mixed layer viscosity mineral include smecton (registered trademark) and Kunipia (registered trademark) (both manufactured by Kunimine Industries, Ltd.) as smectite.

Examples of the film thickening aid include organic solvents having a boiling point higher than that of water and being water-soluble, and examples thereof include butyl cellosolve (ethylene glycol-monobutyl ether) and texanol (2,2,4-trimethylpentane-1,3-diol). Organic solvents such as monoisobutyrate) can be mentioned. Also, the antifreeze agent is typically ethylene glycol. The water-soluble organic solvent refers to an organic solvent that dissolves in water at room temperature (23 ° C.) at a concentration of at least 4.0% by mass. The film thickening aid and the antifreeze agent are also organic solvents, and the content of the film thickening aid in the antifogging layer can be 4.0% by mass or less, preferably 2.0% by mass or less, and is 0. It is more preferably 5.5% by mass or less, and further preferably 0.1% by mass or less. By making it less than 4.0% by mass, it is possible to prevent the organic fine particles (A) themselves from being easily dissolved by the organic solvent, and it is possible to maintain the surface roughness Ra of the anti-fog layer. This is expected to prevent the deterioration of anti-fog property caused by the surface roughness.

The antifungal layer has other components such as a leveling agent, a defoaming agent, a dispersant, a surfactant exemplified as an emulsifier, a viscosity modifier, an antioxidant, an ultraviolet absorber, a plasticizer, and a preservative. , Antifungal agents, water resistant agents and the like may contain additives exemplified. Some of these surfactants and additives may be included as solids in the composition for forming the anti-fog layer. The anti-fog layer may contain a coloring agent such as a coloring pigment or a dye in order to give an aesthetic appearance to the substrate within a range that does not impair the effect of the present invention. The anti-fog layer is derived from the composition for producing the anti-fog layer, and may contain, for example, a pH adjuster, a pH buffer, and the like.

〔substrate〕
The substrate according to one aspect of the present invention includes a substrate layer (a) and an anti-fog layer (b), and the anti-fog layer (b) is arranged on the substrate layer (a). The anti-fog layer (b) is the anti-fog layer according to the above-mentioned aspect of the present invention. The description of the anti-fog layer (b) is based on the description of the anti-fog layer according to one aspect of the present invention, and the same description is not repeated.

The substrate layer (a) is a layer for arranging the anti-fog layer (b) on the substrate layer (a). The material of the substrate layer (a) can be appropriately selected depending on the intended use of the substrate and the like. For example, examples of the substrate layer (a) include glass, resin material, metal, ceramics, and the like, and a composite material thereof may be used. Above all, a plastic having light transmission is more preferable. Examples of the light-transmitting plastic include polycarbonate resin for molding, acrylic resin, polyester resin, polystyrene resin, ABS resin, polyvinyl chloride resin, polyamide resin, polymethylmethacrylate (PMMA), polyethylene terephthalate (PET), and the like. Examples thereof include polycyclohexylene methylene terephthalate copolyester resin (Tritan (registered trademark): manufactured by Eastman Chemical Company, Inc.).

The shape of the substrate layer (a) is not limited as long as the substrate according to one aspect of the present invention includes the anti-fog layer (b). That is, the substrate according to one aspect of the present invention may be a substrate formed into a desired shape according to the intended use. The substrate may be, for example, a substrate having light transmission that constitutes a part of a vehicle such as a passenger car, a lighting device such as a headlamp and a tail lamp in a ship, an aircraft, and the like, and a spectacle lens and the like.

The method of arranging the anti-fog layer (b) on the substrate layer (a) is not particularly limited. For example, the composition for producing the anti-fog layer (b) may be applied onto the substrate layer (a) and then the composition may be cured. The method for curing the composition may be appropriately selected depending on the components of the composition and the like, and may be cured by, for example, drying by heating or the like.

For example, in the substrate layer (a), the surface on which the anti-fog layer (b) is produced is subjected to, for example, a surface treatment for improving the wettability and / or adhesion of the anti-fog layer (b). May be good. Examples of the surface treatment include surface treatments such as corona discharge treatment, chemical conversion treatment, plasma treatment, and acid or alkaline liquid treatment. Further, a surface treatment agent such as a primer and a coupling agent may be applied to the surface of the substrate layer (a) on which the anti-fog layer (b) is formed.

A known method can be adopted as the coating method of the composition according to one aspect of the present invention. For example, the coating method includes a spray coating method, a dip coating method, a roll coating method, a bar coater method and the like. Can be mentioned.

Further, drying and curing after applying the composition according to one aspect of the present invention may be appropriately designed according to the type of the curing agent (B) or the resin (C), and is not limited. , 60 ° C. or higher, preferably 100 ° C. or higher. In the composition according to one aspect of the present invention, the organic fine particles (A) contained in the composition have a high glass transition temperature, so that the aqueous solvent is sufficiently dried and the curing agent (B) is sufficiently crosslinked. It is also one of the advantages that the anti-fog property can be prevented from being lowered by heating the anti-fog layer.

In the preparation of the anti-fog layer, the application and drying of the composition according to one aspect of the present invention and heating may be performed once or may be repeated a plurality of times so as to obtain a desired film thickness. Further, the anti-fog layer may be produced by repeating the application and drying of the composition according to one aspect of the present invention a plurality of times and heating once.

The film thickness of the composition according to one aspect of the present invention after coating and drying, that is, the film thickness of the anti-fog layer is preferably 20 nm to 10000 nm on the surface of the substrate, for example. When the film thickness of the anti-fog layer is 20 nm or more, it is possible to impart suitable anti-fog property to the substrate covered with the anti-fog layer. Further, when the film thickness of the anti-fog layer is 10,000 nm or less, high light transmission can be imparted to the anti-fog layer.

〔Composition〕
The composition for producing the anti-fog layer according to one aspect of the present invention (hereinafter, simply referred to as "the composition according to one aspect of the present invention") contains organic fine particles (A) and water. The particle size (D50) of the organic fine particles (A) is 5 nm or more and 200 nm or less. That is, the composition may be an aqueous composition containing the organic fine particles (A). The description of the composition of the composition according to one aspect of the present invention (including the description of the components described later) is based on the description of the anti-fog layer according to one aspect of the present invention, and the same description is not repeated. By using the composition according to one aspect of the present invention, the anti-fog layer according to one aspect of the present invention can be suitably produced.

It is more preferable that the composition according to one aspect of the present invention contains a curing agent (B). Further, the content of the curing agent (B) is more preferably 1% by mass or more and 30% by mass or less in terms of solid content. By setting the content of the curing agent (B) to 1% by mass or more, an anti-fog layer having good heat resistance can be obtained, and by setting the content of the curing agent (B) to 30% by mass or less, sufficient strength can be obtained. Anti-fog layer can be obtained.

It is preferable that the composition according to one aspect of the present invention further contains a curing agent (B) and a resin (C). Further, it is more preferable that the total amount of the curing agent (B) and the resin (C) is 2% by mass or more and 43% by mass or less in terms of solid content. By setting the total amount of the curing agent (B) and the resin (C) to 2% by mass or more, the adhesion of the anti-fog layer to the substrate can be obtained, and the total amount of the curing agent (B) and the resin (C) is 43% by mass. By setting the content to% or less, the surface roughness for enhancing the anti-fog property can be obtained in the anti-fog layer.

Further, in the composition according to one aspect of the present invention, the content of the organic fine particles (A) is more preferably 58% by mass or more and 99% by mass or less in terms of solid content. This is to preferably produce an anti-fog layer according to one aspect of the present invention.

Further, in the composition according to one aspect of the present invention, the content of the organic solvent is more preferably less than 4% by mass with respect to the solid content. According to the composition according to one aspect of the present invention, water can be used to prepare an anti-fog layer having excellent anti-fog properties, so that the amount of organic solvent used can be reduced. Examples of the organic solvent include the above-mentioned film thickening aid or a water-soluble organic solvent having a boiling point higher than that of water, which is used as a freezing agent.

The composition according to one aspect of the present invention may contain, as a composition for producing an anti-fog layer, 100 parts by mass of the total solid content and 30 to 50,000 parts by mass of water as a solvent. This makes it possible to obtain a composition (coating agent) for producing an anti-fog layer, which can suitably exhibit the anti-fog property of the organic fine particles (A). The water as a solvent can be, for example, deionized water, distilled water, tap water, industrial water and the like. In the present specification, the "solid content" is distinguished from water evaporating from the composition and a volatile solvent, and is included as a composition in the antifogging layer prepared by using the composition according to one aspect of the present invention. If it is an ingredient, it does not necessarily have to be "solid".

Further, by painting and curing the composition according to one aspect of the present invention, an anti-fog layer containing organic fine particles (A) and having a surface roughness Ra of 5 nm or more and 200 nm or less is produced. The method for producing a cloudy layer is also within the scope of the present invention. As described above, by using the composition according to one aspect of the present invention, the anti-fog layer according to one aspect of the present invention can be suitably produced. The base material to which the composition is applied may be appropriately selected according to the purpose of the anti-fog layer.

The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims, and the embodiment obtained by appropriately combining the technical means disclosed in each embodiment is also available. It is included in the technical scope of the present invention.

An embodiment of the present invention will be described below.

The coating agents of Examples 1 to 45 and the coating agents of Comparative Examples 1 to 6 were prepared, and the anti-fog layer prepared from these coating agents was evaluated.

The materials used to prepare each coating agent are as follows.

〔material〕
(Organic fine particles)
It was obtained as an aqueous dispersion of 20% by mass (meth) acrylate copolymer fine particles (manufactured by Takamatsu Oil & Fat Co., Ltd.). Table 2 below shows each monomer constituting the (meth) acrylate copolymer used in Examples and Comparative Examples.

(Inorganic particles)
Alumina sol: Alumina sol 10A (solid content 10% by mass, manufactured by Kawaken Fine Chemical Co., Ltd.)
Colloidal silica: Snowtex (registered trademark) OXS (solid content 10% by mass, manufactured by Nissan Chemical Industries, Ltd.)
(Organic fine particles: resin (C))
Polyester resin;
Pess Resin A-640: Takamatsu Oil and Fat: 25% Solid Polyester Resin; Pess Resin A-645GH: Made by Takamatsu Oil and Fat Co., Ltd .: 30% Solid Polycarbonate Urethane Resin:
Hydran (registered trademark) WLS-210: DIC Corporation: 35% solid content epoxy ester resin:
Watersol (registered trademark) EFD-5560; manufactured by DIC Corporation: 40% solid content alkyd resin:
Watersol (registered trademark) BCD-3100; manufactured by DIC Corporation: 43% solid content water-soluble phenolic resin:
Water-soluble Resol PE-602: Made by DIC Corporation: 42% solid content (absorbent)
Synthetic smectite: smecton (registered trademark) SA (Kunimine Industries, Ltd.)
(Hardener)
Carbodiimide: Carbodilite (registered trademark) E-02 (manufactured by Nisshinbo Chemical Co., Ltd.)
Aziridine: Chemitite (registered trademark) DZ-22E (Nippon Shokubai Co., Ltd.)
Adipic acid dihydrazide (manufactured by Tokyo Chemical Industry Co., Ltd.)
Epoxy compound: Denacol (registered trademark) EX-810 (manufactured by Nagase ChemteX Corporation)
Blocked isocyanate: Duranate (registered trademark) WM44-L70G (manufactured by Asahi Kasei Corporation)
Oxazoline compound: Epocross (registered trademark) WS-700 (manufactured by Nippon Shokubai Co., Ltd.)
(Film formation aid)
Butyl cellosolve (manufactured by Tokyo Chemical Industry Co., Ltd.)

[Preparation]
The coating agent of Example 1 was prepared by the following procedure. First, 500 g of an aqueous dispersion of (meth) acrylate copolymer fine particles was prepared, and 20 g of an aqueous dispersion of polyester resin was added to the aqueous dispersion. Next, 10 g of an aqueous dispersion of alumina sol and 10 g of carbodiimide in terms of solid content as a curing agent were added to the aqueous dispersion of the (meth) acrylate copolymer fine particles. Then, the aqueous dispersion was stirred and adjusted to pH 8.0 by adding aqueous ammonia (1 mol / L) to obtain the coating agent of Example 1. According to the compositions shown in Tables 2 to 4 below, the coating agents of Examples 2 to 45 and Comparative Examples 1 to 6 were prepared by the same procedure as the coating agent of Example 1.

[Preparation of anti-fog layer]
A polycarbonate test piece (thickness 2 mm) was coated with the coating agent of Example 1 using bar coater # 2. Then, the test piece coated with the coating agent was heated at a temperature of 90 ° C. for 20 minutes to dry and cure the coating agent. As a result, a test piece provided with an anti-fog layer having a film thickness of about 1 μm was produced. The same procedure as the preparation of the anti-fog layer with the coating agent of Example 1 Therefore, a test piece provided with the anti-fog layer of Examples 2 to 45 and Comparative Examples 1 to 6 was prepared.

[Each evaluation]
The following evaluations were performed using the test pieces provided with the anti-fog layers of Examples 1 to 45 and Comparative Examples 1 to 6. The evaluation results are shown in Tables 5 to 7.

(Particle size)
The particle size (unit: nm) of the organic fine particles was evaluated as a particle size corresponding to a cumulative total of 50% on a volume basis. The particle size of the organic fine particles was measured with a dynamic light scattering type particle size distribution measuring device (device name: Nanotrac Wave II UT151, manufactured by Microtrac Bell). Nanotrac is a registered trademark of the company.

(Glass transition temperature (Tg) of organic fine particles)
The glass transition temperature (Tg) of the organic fine particles was measured using DSC (differential scanning calorimetry, device name: EXSTAR DSC6200, manufactured by Seiko Instruments). The glass transition temperature (Tg) of the organic fine particles was determined from the DSC curve measured by measuring the DSC curve according to JIS-K-7122: 2012. The mass of the sample used for the DSC measurement was 5 mg. In the first scan, the temperature range from -10 ° C to 300 ° C is raised at a rate of 20 ° C / min, then the sample is cooled with liquid nitrogen, and then in the second scan, from -10 ° C. The temperature range up to 300 ° C. was raised at a rate of 20 ° C./min, and the glass transition temperature of the organic fine particles was derived from the DSC curve obtained in the second scan.

(Surface roughness Ra)
The surface roughness Ra of the antifogging layer was measured according to JIS-B-0601-2013 using a surface roughness measuring instrument [manufactured by Kosaka Laboratory Co., Ltd., model name Surfcorer SE500], with a scanning range of 4 mm and a scanning speed of 0. It was determined under the condition of .2 mm / s.

(Atomic force microscope observation)
Using an AFM (atomic force microscope, device name: Distance3100, manufactured by Veeco), an antifogging layer prepared from the coating agent of Example 32 was observed with an atomic force microscope. The results are shown in FIG.

(Glass transition temperature (Tg) of anti-fog layer)
The glass transition temperature Tg of the antifogging layer was measured by DSC (differential scanning calorimetry, device name: EXSTAR DSC6200, manufactured by Seiko Instruments). The sample mass of the antifogging layer is 5 mg, and the temperature range, the rate of temperature rise, and the number of scans for obtaining the DSC curve are the same as the conditions for obtaining the DSC curve of the glass transition temperature (Tg) of the organic fine particles. Therefore, the description is omitted.

(Water contact angle)
The water contact angle of the anti-fog layer was measured using a contact angle meter (device name: CV-DT · A type, manufactured by Kyowa Interface Science Co., Ltd.).

(Transparency of coating film)
The transparency (light transmittance) of the coating film of the test piece provided with the anti-fog layer was measured using a haze meter (“HAZE MTER NDH5000”, manufactured by Nippon Denshoku Kogyo Co., Ltd.). The HAZE value was measured in accordance with JIS-K7361-1: 1997 under the conditions that the light source was a white LED and the luminous flux was 14 mm. It was evaluated as more preferable. The HAZE value of the polycarbonate test piece itself having a thickness of 2 mm was 0.30.
〇: The HAZE value was 0.30 or more and less than 0.40.
Δ: The HAZE value was 0.40 or more and less than 0.50.
X: The HAZE value was 0.50 or more.

(Anti-fog)
In a room air-conditioned at a temperature of 23 ° C. and a humidity of 50%, exhaled air was blown onto the anti-fog layer prepared on the test piece for 5 seconds, and the anti-fog property was evaluated according to the following criteria.
⊚: No cloudiness at all.
〇: It becomes slightly cloudy, but it returns to its original state soon.
Δ: Slightly cloudy.
×: It becomes cloudy.

(Heat-resistant)
Each test piece was allowed to stand for 240 hours according to the respective temperature conditions of 80 ° C., 100 ° C., and 110 ° C., and then allowed to stand in a constant temperature chamber air-conditioned at a temperature of 23 ° C. and a humidity of 50% for 1 hour. After that, anti-fog property and light transmission were evaluated.

(Gloss value)
The gloss value was measured using a 3-angle surface gloss meter (device name: Microtrigloss, manufactured by BYK). To measure the gloss value, place 10 sheets of A4 copy paper (manufactured by Itochu Pulp & Paper Co., Ltd., whiteness 92%) on top of each other, and set a test piece on which the anti-fog layer of each example and comparative example is prepared. Measured at.

As shown in Tables 5 to 7, according to the anti-fog layer according to one aspect of the present invention, it was shown that the anti-fog property is excellent. Further, it was shown that when the Tg was 110 ° C. or higher, the anti-fog property after the heat resistance test was also excellent.

Claims (17)

It contains organic fine particles (A) and has a surface roughness Ra of 5 nm or more and 200 nm or less.
A composition for producing an anti-fog layer,
Organic fine particles (A) and
Including water
The particle size D50 of the organic fine particles (A) is 5 nm or more and 200 nm or less.
The organic fine particles (A) are (meth) acrylate copolymers, and the organic fine particles (A) are
The (meth) acrylate copolymer is a copolymer formed from a monomer mixture, and is a copolymer.
A composition having an average SP value (solubility parameter) of the monomer mixture of 21 MPa ^1/2 or more and 32 MPa ^1/2 or less . It contains organic fine particles (A) and has a surface roughness Ra of 5 nm or more and 200 nm or less.
It ’s an anti-fog layer,
Contains organic fine particles (A)
The particle size D50 of the organic fine particles (A) is 5 nm or more and 200 nm or less.
The organic fine particles (A) are (meth) acrylate copolymers, and the organic fine particles (A) are
The (meth) acrylate copolymer is a copolymer formed from a monomer mixture, and is a copolymer.
An anti- fog layer having an average SP value (solubility parameter) of the monomer mixture of 21 MPa ^1/2 or more and 32 MPa ^1/2 or less . The content of the organic fine particles (A) is 58 to 99% by mass.
The anti-fog layer according to claim 2 . The glass transition temperature (Tg) is 60 ° C. or higher.
The anti-fog layer according to claim 2 or 3 . The contact angle with water is less than 10 °,
The anti-fog layer according to any one of claims 2 to 4 . Substrate layer (a) and
With an anti-fog layer (b)
The anti-fog layer (b) is the anti-fog layer according to any one of claims 2 to 5 , and is arranged on the substrate layer (a).
substrate. The substrate layer (a) is a light-transmitting plastic.
The substrate according to claim 6 . The glass transition temperature (Tg) of the organic fine particles (A) is 60 ° C. or higher.
The composition according to claim 1 . Further containing the curing agent (B),
The content of the curing agent (B) is 1% by mass or more and 30% by mass or less in terms of solid content.
The composition according to claim 1 or 8. The content of the organic fine particles (A) is 58% by mass or more and 99% by mass or less in terms of solid content.
The composition according to any one of claims 1, 8 and 9. The content of the organic solvent is less than 4% by mass with respect to the solid content.
The composition according to any one of claims 1 and 8 to 10. The organic fine particles (A) are (meth) acrylate copolymers, and the organic fine particles (A) are
The (meth) acrylate copolymer is a copolymer obtained by polymerizing a monomer mixture.
The composition according to any one of claims 1 and 8 to 11. The monomer mixture contains a vinyl-based monomer having at least one crosslinked functional group selected from the group consisting of an N-methylol group, an N-alkoxymethylol group, an N-methylol ether group and a hydroxyl group.
The composition according to claim 12. Further containing a curing agent (B) and a resin (C),
The total amount of the curing agent (B) and the resin (C) is 2% by mass or more and 43% by mass or less in terms of solid content.
The composition according to any one of claims 1 and 8 to 13. Further comprising at least one inorganic particle selected from the group consisting of alumina and silica.
The composition according to any one of claims 1 and 8 to 14 . The composition according to claim 14, wherein the resin (C) is selected from a water-soluble resin, a water-dispersible resin, and a resin emulsion. By painting and curing the composition according to any one of claims 1 and 8 to 16 .
To prepare an anti-fog layer containing organic fine particles (A) and having a surface roughness Ra of 5 nm or more and 200 nm or less.
Manufacturing method of anti-fog layer.

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