WO2016194875A1

WO2016194875A1 - Optical reflection film

Info

Publication number: WO2016194875A1
Application number: PCT/JP2016/065930
Authority: WO
Inventors: 翔太畠沢
Original assignee: コニカミノルタ株式会社
Priority date: 2015-06-01
Filing date: 2016-05-30
Publication date: 2016-12-08
Also published as: JPWO2016194875A1; CN107615117B; JP6724912B2; CN107615117A

Abstract

[Problem] To provide an optical reflection film having a refractive index layer that includes a water-soluble resin, wherein there is little coating failure and little cracking even after a long period of use. [Solution] An optical reflection film that is provided with a substrate and a dielectric multilayer film disposed on one surface of the substrate and formed by alternately layering low refractive index layers and high refractive index layers. At least one of the low refractive index layers and high refractive index layers is a water-dispersible hydrophobic resin–containing layer that includes a water-soluble resin and 5–55 mass%, relative to the total mass of the layer, of a water-dispersible hydrophobic resin.

Description

Optical reflective film

The present invention relates to an optical reflection film.

In general, a dielectric multilayer film in which a high refractive index layer and a low refractive index layer are laminated on the surface of a substrate by adjusting the optical film thickness can selectively reflect light of a specific wavelength. Are known. Such a dielectric multilayer film is used, for example, as an optical reflection film installed on a building window or a vehicle member. Such an optical reflection film transmits visible light and selectively shields near infrared rays, but the reflection wavelength can be controlled only by adjusting the film thickness and refractive index of each layer. Can be reflected.

As a method of forming a multilayer body such as a dielectric multilayer film, there is generally a method of laminating by a dry film forming method. However, formation of a dielectric multilayer film by a dry film forming method requires a lot of manufacturing costs. Not practical. Practical methods include, for example, a method of applying and laminating a coating solution containing a mixture of a water-soluble resin and metal oxide particles by a wet coating method. In particular, the method of manufacturing by simultaneously applying the coating solution for the high refractive index layer and the coating solution for the low refractive index layer is excellent from the viewpoint of cost.

However, it is known that moisture absorption and desorption easily occurs in a laminated body in which a plurality of layers are formed by applying a coating solution containing a water-soluble resin. Cracks occur over time due to repeated shrinkage and expansion of each layer due to moisture absorption and desorption.

In order to improve the water resistance of a laminate comprising a water-soluble resin, for example, JP 2012-973 A discloses that a coating solution contains a cross-linking agent, and the water-soluble resin and the cross-linking agent are present at the interface between adjacent layers. And a method for suppressing the mixing of moisture is disclosed.

As described in JP 2012-973 A, the water resistance of the laminate can be improved by using a water-soluble resin in combination with a crosslinking agent. However, in the method described in Japanese Patent Application Laid-Open No. 2012-973, an unreacted crosslinking agent remains after coating and drying of the coating solution. Therefore, the crosslinking agent reacts with time to cause shrinkage due to post-curing of the coating film. Arise. As a result, it was found that the generation of cracks when exposed to a high humidity environment for a long period of time was further deteriorated. In order to carry out the reaction so that unreacted cross-linking agent does not remain, a high temperature close to 100 ° C. is necessary, which is not realistic because it exceeds the glass transition temperature of the resin base material.

Accordingly, the present invention has been made in view of the above circumstances, and in an optical reflective film having a refractive index layer containing a water-soluble resin, an optical film with little coating film failure and less cracking even when used for a long period of time. An object is to provide a reflective film.

As a result of intensive studies to solve the above problems, the present inventors have found that the object of the present invention can be achieved by adopting the following configuration.

That is, the above-mentioned problem of the present invention is solved by the following means.

1. A substrate;
A dielectric multilayer film in which low-refractive index layers and high-refractive index layers are alternately stacked, disposed on one surface of the substrate;
At least one of the low refractive index layer and the high refractive index layer includes a water-soluble resin and a water-dispersible hydrophobic resin containing 5 to 55% by mass of a water-dispersible hydrophobic resin based on the total mass. An optical reflection film which is a containing layer.

2. The water-dispersible hydrophobic resin-containing layer further contains an anionic surfactant, and the water-dispersible hydrophobic resin is an anionic emulsion resin. The optical reflective film as described in 2.

3. In the dielectric multilayer film, the uppermost layer opposite to the side in contact with the base material is the water-dispersible hydrophobic resin-containing layer. Or 2. The optical reflective film as described in 2.

4. In the dielectric multilayer film, the lowest layer in contact with the substrate is the water-dispersible hydrophobic resin-containing layer. ~ 3. The optical reflective film of any one of these.

5. The top layer and the bottom layer of the dielectric multilayer film are low refractive index layers, and all the low refractive index layers are the water-dispersible hydrophobic resin-containing layers. ~ 4. The optical reflective film of any one of these.

6. 1. The average degree of polymerization of the water-soluble resin in the water-dispersible hydrophobic resin-containing layer is from 4000 to 6000. ~ 5. The optical reflective film of any one of these.

7). A step of preparing a coating solution by dissolving or dispersing a water-soluble resin, an anionic surfactant, and an anionic emulsion resin in an aqueous solvent;
Forming the water-dispersible hydrophobic resin-containing layer by applying the coating liquid;
Including the above 2. The manufacturing method of the optical reflection film of description.

Hereinafter, embodiments of the present invention will be described.

One embodiment of the present invention includes a base material, and a dielectric multilayer film in which low refractive index layers and high refractive index layers are alternately stacked, which are disposed on one surface of the base material. At least one of the low refractive index layer and the high refractive index layer contains a water-soluble resin and a water-dispersible hydrophobic resin containing 5 to 55% by mass of a water-dispersible hydrophobic resin based on the total mass. It is an optical reflection film which is a resin containing layer.

According to the present invention, in an optical reflective film having a refractive index layer containing a water-soluble resin, an optical reflective film with few coating film failures and few cracks even when used for a long time can be obtained.

The optical reflective film of the present invention contains a water-soluble resin in at least one refractive index layer among the high refractive index layer and the low refractive index layer. Here, as described above, the optical reflective film containing the water-soluble resin has a problem that cracks occur with time.

Therefore, the present inventors examined cracks in the optical reflection film, and reduced the expansion and contraction of the refractive index layer by using a predetermined amount of water-dispersible hydrophobic resin together with the water-soluble resin. It was found that cracking with time can be reduced. When a water-dispersible hydrophobic resin is added to a water-soluble resin, when the resin is fused and formed into a film, a membrane having higher hydrophobicity is obtained than when no water-dispersible hydrophobic resin is added. . Therefore, it is considered that the occurrence of cracks can be prevented because the expansion and contraction of the film due to the change in the amount of moisture in the atmosphere can be reduced. Moreover, the coating film can be softened by containing the emulsion resin, and coating film failure can be reduced. In particular, combining an anionic surfactant with an anionic water-dispersible hydrophobic resin increases the stability of the water-dispersible hydrophobic resin in the coating solution and suppresses local agglomeration during coating film drying. It is considered that coating film failure can be further reduced.

Here, by setting the content of the water-dispersible hydrophobic resin to 5 to 55% by mass with respect to the total mass (solid content mass) of the water-dispersible hydrophobic resin-containing layer, an excellent crack prevention effect can be obtained. can get. Moreover, coating film failure can be reduced. When the content of the water-dispersible hydrophobic resin is less than 5% by mass, fusion between the water-dispersible hydrophobic resins is reduced, and the effects of the present invention cannot be sufficiently obtained. On the other hand, when the content of the water-dispersible hydrophobic resin is more than 55% by mass, it is easy to form a void with the water-soluble resin and the coating film haze is likely to increase. On the other hand, when the content of the water-dispersible hydrophobic resin is more than 55% by mass, the viscosity of the coating solution is lowered during aqueous coating, particularly simultaneous multi-layer coating. Therefore, it is difficult to form a uniform coating film, and cracks with time are likely to occur. Also, coating film failure is likely to occur. Furthermore, mixing of the refractive index layers occurs due to a decrease in the viscosity of the coating solution, and haze is likely to occur. Preferably, the content of the water-dispersible hydrophobic resin is 10 to 40% by mass, more preferably 10 to 30% by mass, based on the total mass of the water-dispersible hydrophobic resin-containing layer. When two or more types of water-dispersible hydrophobic resins are used, the total amount is adjusted to be in the above range. When two or more water-dispersible hydrophobic resin-containing layers are included, the content of at least one water-dispersible hydrophobic resin may be in the above range, but it is more preferable that all layers have the above range.

Hereinafter, the components of the optical reflection film of the present invention will be described in detail. Hereinafter, when the low refractive index layer and the high refractive index layer are not distinguished, the concept including both is referred to as a “refractive index layer”.

In this specification, “X to Y” indicating a range means “X or more and Y or less”. Unless otherwise specified, measurements such as operation and physical properties are performed under conditions of room temperature (20 to 25 ° C.) / Relative humidity 40 to 50%.

[Optical reflection film]
An optical reflective film according to the present invention comprises a base material, and a dielectric multilayer film formed by alternately laminating low refractive index layers and high refractive index layers disposed on one surface of the base material. Have.

[Base material]
The optical reflective film according to the present invention includes a base material for supporting a dielectric multilayer film or the like. As the substrate, various resin films can be used, such as polyolefin films (polyethylene, polypropylene, etc.), polyester films (polyethylene terephthalate (PET), polyethylene naphthalate, etc.), polyvinyl chloride, cellulose acetate, etc. A polyester film is preferable. Although it does not specifically limit as a polyester film (henceforth polyester), It is preferable that it is polyester which has the film formation property which has a dicarboxylic acid component and a diol component as main structural components.

The main constituent dicarboxylic acid components include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenylethanedicarboxylic acid, Examples thereof include cyclohexane dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl thioether dicarboxylic acid, diphenyl ketone dicarboxylic acid, and phenylindane dicarboxylic acid. Examples of the diol component include ethylene glycol, propylene glycol, tetramethylene glycol, cyclohexanedimethanol, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyethoxyphenyl) propane, bis ( 4-Hydroxyphenyl) sulfone, bisphenol fluorene hydroxyethyl ether, diethylene glycol, neopentyl glycol, hydroquinone, cyclohexanediol and the like. Among the polyesters having these as main components, from the viewpoints of transparency, mechanical strength, dimensional stability, etc., dicarboxylic acid components such as terephthalic acid, 2,6-naphthalenedicarboxylic acid, diol components such as ethylene glycol and 1 Polyester having 1,4-cyclohexanedimethanol as the main constituent is preferred. Among these, polyesters mainly composed of polyethylene terephthalate and polyethylene naphthalate, copolymerized polyesters composed of terephthalic acid, 2,6-naphthalenedicarboxylic acid and ethylene glycol, and mixtures of two or more of these polyesters are mainly used. Polyester as a constituent component is preferable.

The thickness of the substrate used in the present invention is preferably 10 to 300 μm, particularly 20 to 150 μm. In addition, two substrates may be stacked, and in this case, the type may be the same or different.

The base material preferably has a visible light region transmittance of 85% or more shown in JIS R3106-1998, and particularly preferably 90% or more. When the base material has the above transmittance or more, it is advantageous in that the transmittance in the visible light region shown in JIS R3106-1998 is 50% or more (upper limit: 100%) when a laminated film is formed. preferable.

In addition, the base material using the resin or the like may be an unstretched film or a stretched film. A stretched film is preferable from the viewpoint of strength improvement and thermal expansion suppression.

The base material can be manufactured by a conventionally known general method. For example, an unstretched substrate that is substantially amorphous and not oriented can be produced by melting a resin as a material with an extruder, extruding it with an annular die or a T-die, and quenching. In addition, the unstretched base material is subjected to a known method such as uniaxial stretching, tenter-type sequential biaxial stretching, tenter-type simultaneous biaxial stretching, tubular-type simultaneous biaxial stretching, or the flow direction of the base material (vertical axis), or A stretched substrate can be produced by stretching in the direction perpendicular to the flow direction of the substrate (horizontal axis). The draw ratio in this case can be appropriately selected according to the resin as the raw material of the base material, but is preferably 2 to 10 times in each of the vertical axis direction and the horizontal axis direction.

[Dielectric multilayer film]
The dielectric multilayer film has a configuration in which low refractive index layers and high refractive index layers are alternately stacked, and has at least one unit composed of a low refractive index layer and a high refractive index layer. Since the dielectric multilayer film includes the refractive index layers having different refractive indexes in this way, when light having a predetermined wavelength (for example, infrared light) is incident, at least a part of this light is It can reflect and can exhibit the shielding effect (and heat shielding effect in the case of infrared light).

In this embodiment, whether the refractive index layer constituting the dielectric multilayer film is a low refractive index layer or a high refractive index layer is determined by comparing the refractive index with the adjacent refractive index layer. Specifically, when a refractive index layer is used as a reference layer, if the refractive index layer adjacent to the reference layer has a lower refractive index than the reference layer, the reference layer is a high refractive index layer (the adjacent layer is a low refractive index layer). It is judged to be a rate layer. On the other hand, if the refractive index of the adjacent layer is higher than that of the reference layer, it is determined that the reference layer is a low refractive index layer (the adjacent layer is a high refractive index layer). Therefore, whether the refractive index layer is a high refractive index layer or a low refractive index layer is a relative one determined by the relationship with the refractive index of the adjacent layer. Depending on the relationship, it can be a high refractive index layer or a low refractive index layer.

As the refractive index layer, at least one refractive index layer of the high refractive index layer and the low refractive index layer constituting the dielectric multilayer film is 5 to 5 with respect to the water-soluble resin and the total mass of the refractive index layer. If it is a water dispersible hydrophobic resin containing layer containing 55 mass% water dispersible hydrophobic resin, there will be no restriction | limiting in particular, The well-known refractive index layer used in the said technical field may be used. As the known refractive index layer, for example, a refractive index layer formed by a wet film forming method is preferably used from the viewpoint of manufacturing efficiency.

Further, from the viewpoint of reflection characteristics, at least one of the high refractive index layer and the low refractive index layer preferably includes metal oxide particles, and both the high refractive index layer and the low refractive index layer include metal oxide particles. It is more preferable.

Further, as described above, in the dielectric multilayer film of the optical reflecting film of the present invention, a water-soluble resin is used for at least one of the high refractive index layer and the low refractive index layer. Moreover, it is preferable that the refractive index layer of the optical reflection film formed by the wet film forming method is a coating film coated with a coating solution containing a water-soluble resin (usually containing an aqueous solvent such as water). The water-soluble resin is preferable because it does not use an organic solvent, has a low environmental load, and has high flexibility, so that the durability of the film during bending is improved. The water-soluble resin is preferably used particularly when metal oxide particles are included in at least one of the high refractive index layer and the low refractive index layer.

In this specification, “water-soluble” means a G2 glass filter (maximum pores 40 to 50 μm) when dissolved in water so as to have a concentration of 0.5% by mass at the temperature at which the substance is most dissolved. This means that the mass of insoluble matter to be filtered out is within 50% by mass of the added polymer.

As described above, whether the layer is a low refractive index layer or a high refractive index layer is a relative one that is determined by the relationship with the adjacent refractive index layer. The structure of a typical high refractive index layer and low refractive index layer among the refractive index layers that can be formed by the respective methods will be described below.

(High refractive index layer)
The high refractive index layer preferably contains a water-soluble resin. In addition, metal oxide particles, a curing agent, a surfactant, and other additives may be included as necessary. The water-soluble resin and metal oxide particles contained in the high refractive index layer are hereinafter referred to as “first water-soluble resin” and “first metal oxide particles” for convenience.

At this time, the refractive index of the first metal oxide particles is preferably higher than the refractive index of the second metal oxide particles contained in the low refractive index layer described later. By containing metal oxide particles in the high refractive index layer and / or the low refractive index layer, the difference in refractive index between the refractive index layers can be increased, and the transparency of the film is increased by reducing the number of layers. This is preferable because it can be performed. In addition, there is an advantage that stress relaxation works and film properties (flexibility at the time of bending and high temperature and high humidity) are improved. The metal oxide particles may be contained in any one of the refractive index layers, but a preferable form is that at least the high refractive index layer includes metal oxide particles, and more preferable forms are the high refractive index layer and the low refractive index layer. All of the rate layers are in a form containing metal oxide particles.

(1) First water-soluble resin The first water-soluble resin is not particularly limited, and polyvinyl alcohol resins, gelatin, celluloses, thickening polysaccharides, and polymers having reactive functional groups can be used. . Of these, it is preferable to use a polyvinyl alcohol-based resin.

Polyvinyl alcohol resin As the polyvinyl alcohol resin, ordinary polyvinyl alcohol obtained by hydrolyzing polyvinyl acetate (unmodified polyvinyl alcohol), cation-modified polyvinyl alcohol, anion-modified polyvinyl alcohol, nonion-modified polyvinyl alcohol, vinyl alcohol Examples thereof include modified polyvinyl alcohol such as a polymer. The modified polyvinyl alcohol may improve the film adhesion, water resistance, and flexibility.

Gelatin As the gelatin, various gelatins that have been widely used in the field of silver halide photographic light-sensitive materials can be applied. For example, acid-treated gelatin, alkali-treated gelatin, enzyme-treated gelatin that undergoes enzyme treatment in the production process of gelatin, a group having an amino group, imino group, hydroxyl group, carboxyl group as a functional group in the molecule, and a group that can react with it And gelatin derivatives modified by treatment with a reagent having

When gelatin is used, a gelatin hardener can be added as necessary.

Cellulose As the cellulose, a water-soluble cellulose derivative can be preferably used. For example, water-soluble cellulose derivatives such as carboxymethyl cellulose (cellulose carboxymethyl ether), methyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose; carboxylic acid group-containing celluloses such as carboxymethyl cellulose (cellulose carboxymethyl ether) and carboxyethyl cellulose; Examples thereof include cellulose derivatives such as cellulose, cellulose acetate propionate, cellulose acetate, and cellulose sulfate.

Thickening polysaccharides Thickening polysaccharides are saccharide polymers that have many hydrogen bonding groups in the molecule. The thickening polysaccharide has a characteristic that the viscosity difference at low temperature and the viscosity at high temperature are large due to the difference in hydrogen bonding force between molecules depending on temperature. In addition, when metal oxide particles are added to the thickening polysaccharide, the viscosity is increased due to hydrogen bonding with the metal oxide particles at low temperatures. As for the viscosity increase range, the viscosity at 15 ° C. is usually 1.0 mPa · s or more, preferably 5.0 mPa · s or more, more preferably 10.0 mPa · s or more.

The thickening polysaccharide that can be used is not particularly limited, and examples include generally known natural polysaccharides, natural complex polysaccharides, synthetic simple polysaccharides, and synthetic complex polysaccharides. The details of these polysaccharides can be referred to “Biochemical Dictionary (2nd edition), Tokyo Chemical Doujinshi”, “Food Industry”, Vol. 31, (1988), p.

Polymers having reactive functional groups Examples of polymers having reactive functional groups include polyvinylpyrrolidones; polyacrylic acid, acrylic acid-acrylonitrile copolymer, potassium acrylate-acrylonitrile copolymer, vinyl acetate-acrylic ester Acrylic resins such as copolymers, acrylic acid-acrylic acid ester copolymers; styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene-methacrylic acid-acrylic acid ester copolymers, styrene-α -Styrene acrylic resins such as methylstyrene-acrylic acid copolymer and styrene-α-methylstyrene-acrylic acid-acrylic acid ester copolymer; styrene-sodium styrenesulfonate copolymer, styrene-2-hydroxyethyl acrylate Copolymer, styrene -2-hydroxyethyl acrylate-potassium styrene sulfonate copolymer, styrene-maleic acid copolymer, styrene-maleic anhydride copolymer, vinyl naphthalene-acrylic acid copolymer, vinyl naphthalene-maleic acid copolymer; And vinyl acetate-based copolymers such as vinyl acetate-maleic acid ester copolymer, vinyl acetate-crotonic acid copolymer, vinyl acetate-acrylic acid copolymer; and salts thereof. Of these, polyvinylpyrrolidones and copolymers containing the same are preferably used.

The above water-soluble resins may be used alone or in combination of two or more.

The weight average molecular weight of the first water-soluble resin is preferably 1000 to 200000, more preferably 3000 to 40000. In the present specification, the value measured by gel permeation chromatography (GPC) is adopted as the value of “weight average molecular weight”.

The content of the first water-soluble resin is preferably 5 to 50% by mass and more preferably 10 to 40% by mass with respect to 100% by mass of the solid content of the high refractive index layer.

(2) First Metal Oxide Particles The first metal oxide particles are not particularly limited, but are preferably metal oxide particles having a refractive index of 2.0 to 3.0. Specifically, titanium oxide, zirconium oxide, zinc oxide, alumina, colloidal alumina, lead titanate, red lead, yellow lead, zinc yellow, chromium oxide, ferric oxide, iron black, copper oxide, magnesium oxide, water Examples thereof include magnesium oxide, strontium titanate, yttrium oxide, niobium oxide, europium oxide, lanthanum oxide, zircon, and tin oxide. Among these, the first metal oxide particles are preferably titanium oxide or zirconium oxide from the viewpoint of forming a transparent and high refractive index layer having a high refractive index. From the viewpoint of improving weather resistance, the first metal oxide particles are preferably a rutile type (tetragonal type). ) Titanium oxide is more preferable.

Further, the titanium oxide may be in the form of core / shell particles coated with a silicon-containing hydrated oxide. The core / shell particles have a structure in which the surface of the titanium oxide particles is coated with a shell made of a silicon-containing hydrated oxide on titanium oxide serving as a core. In this case, the volume average particle diameter of the titanium oxide particles serving as the core portion is preferably more than 1 nm and less than 30 nm, and more preferably 4 nm or more and less than 30 nm. By including such core / shell particles, the intermixing of the high refractive index layer and the low refractive index layer can be suppressed by the interaction between the silicon-containing hydrated oxide of the shell layer and the water-soluble resin. .

The first metal oxide particles described above may be used alone or in combination of two or more.

The content of the first metal oxide particles is 15 to 80% by mass with respect to 100% by mass of the solid content of the high refractive index layer from the viewpoint of increasing the refractive index difference from the low refractive index layer. It is preferably 20 to 77% by mass, more preferably 30 to 75% by mass.

The volume average particle diameter of the first metal oxide particles is preferably 30 nm or less, more preferably 1 to 30 nm, and even more preferably 5 to 15 nm. A volume average particle size of 30 nm or less is preferred because it has less haze and is excellent in visible light transmittance. In the present specification, the value measured by the following method is adopted as the value of “volume average particle diameter”. Specifically, arbitrary 1000 particles appearing on the cross section and surface of the refractive index layer are observed with an electron microscope to measure the particle diameter, and particles having particle diameters of d1, d2,. In the group of n1, n2... Ni... Nk metal oxide particles, where the volume per particle is vi, the volume average particle diameter (mv) is calculated by the following formula.

(3) Curing Agent The curing agent has a function of reacting with the first water-soluble resin (preferably polyvinyl alcohol resin) contained in the high refractive index layer to form a hydrogen bond network.

The curing agent is not particularly limited as long as it causes a curing reaction with the first water-soluble resin, but in general, a compound having a group capable of reacting with the water-soluble resin or a different group possessed by the water-soluble resin. The compound which accelerates | stimulates mutual reaction is mentioned.

As a specific example, when a polyvinyl alcohol-based resin is used as the first water-soluble resin, it is preferable to use boric acid and its salt as a curing agent. Moreover, you may use well-known hardening | curing agents other than boric acid and its salt.

In addition, boric acid and its salt mean oxygen acid and its salt having a boron atom as a central atom. Specific examples include orthoboric acid, diboric acid, metaboric acid, tetraboric acid, pentaboric acid, octaboric acid, and salts thereof.

The content of the curing agent is preferably 1 to 10% by mass and more preferably 2 to 6% by mass with respect to 100% by mass of the solid content of the high refractive index layer.

In particular, when the polyvinyl alcohol resin is used as the first water-soluble resin, the total amount of the curing agent used is preferably 1 to 600 mg per 1 g of polyvinyl alcohol resin, and 10 to 600 mg per 1 g of polyvinyl alcohol resin. It is more preferable that

Surfactant Surfactant is not particularly limited, but includes amphoteric surfactant, cationic surfactant, anionic surfactant, nonionic surfactant, fluorosurfactant and silicon surfactant. Is mentioned. Among these, acrylic surfactants, silicon surfactants, or fluorine surfactants are used. As the surfactant, a surfactant containing a long-chain alkyl group is preferable, and a surfactant having an alkyl group having 6 to 20 carbon atoms is more preferable.

Zwitterionic surfactants include alkylbetaines, alkylamine oxides, cocamidopropyl betaines, lauramidopropyl betaines, palm kernel fatty acid amidopropyl betaines, cocoamphoacetic acid N, lauroamphoacetic acid Na, lauramidopropyl hydroxysultain, lauramide Examples include propylamine oxide, myristamidopropylamine oxide, hydroxyalkyl (C12-14) hydroxyethyl sarcosine.

Examples of the cationic surfactant include alkylamine salts and quaternary ammonium salts.

An anionic surfactant is a surfactant in which a hydrophilic group is ionized to an anion in an aqueous solution, and examples of the anionic surfactant include a sulfate ester salt, a sulfonate salt, a carboxylate salt, and a phosphate ester salt. It is done. For example, alkyl sulfate ester salt, polyoxyethylene alkyl ether sulfate ester salt, polyoxyethylene aryl ether sulfate ester salt, alkylbenzene sulfonate salt, fatty acid salt, polyoxyethylene alkyl ether phosphate salt, and dipotassium alkenyl succinate can be used. . Examples of commercially available anionic surfactants include, for example, Emar (registered trademark) manufactured by Kao Corporation, Hytenol (registered trademark) NF-08, NF-0825, NF-manufactured by Daiichi Kogyo Co., Ltd. 13, NF-17 (both polyoxyethylene styrenated phenyl ether ammonium sulfate) and the like, and examples of the sulfonate include Neo-Perex (registered trademark) and Perex (registered trademark) manufactured by Kao Corporation. Examples of the carboxylate include Neo Haitenol (registered trademark) manufactured by Daiichi Kogyo Seiyaku Co., Ltd., and examples of the phosphate ester salt include Prisurf (registered trademark) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. . In the present invention, a sulfate ester salt or a sulfonate salt is preferable from the viewpoint of miscibility with the liquid.

Nonionic surfactants include polyoxyethylene alkyl ethers (for example, Emulgen (registered trademark) manufactured by Kao Corporation), polyoxyethylene sorbitan fatty acid esters (for example, Leodol (registered trademark) TW series manufactured by Kao Corporation), glycerin. Examples include fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene alkylamines, and alkyl alkanolamides. Alternatively, polyoxyethylene alkyl ethers include polyoxyethylene mono 2-ethylhexyl ether, polyoxyethylene decyl ether (for example, Neugen (registered trademark) XL-40, XL-50, XL-60 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) Etc.) can also be used.

Fluorosurfactants include Surflon S-211, S-221, S-231, S-241, S-242, S-243, S-420 (manufactured by AGC Seimi Chemical Co., Ltd.), Megafac F-114 F-410, F-477, F-553 (manufactured by DIC Corporation), FC-430, FC-4430, FC-4432 (manufactured by 3M Corporation).

Examples of silicon surfactants include BYK-345, BYK-347, BYK-348, and BYK-349 (manufactured by Big Chemie Japan Co., Ltd.).

The high refractive index layer can also contain other additives. Examples of other additives include amino acids and lithium compounds. Further, ultraviolet absorbers described in JP-A-57-74193, JP-A-57-87988, JP-A-62-261476; JP-A-57-74192, JP-A-57-87989 No. 5, JP-A-60-72785, JP-A 61-146591, JP-A-1-95091, JP-A-3-13376, etc .; Optical brighteners described in JP-A No. 59-52689, JP-A 62-280069, JP-A 61-242871, JP-A 4-219266, etc .; sulfuric acid, phosphoric acid , Acetic acid, citric acid, sodium hydroxide, potassium hydroxide, potassium carbonate and other pH adjusters; antifoaming agents; lubricants such as diethylene glycol; antiseptics; antifungal agents; antistatic agents; matting agents; Antioxidants; Flame retardants; Crystal nucleating agents; Inorganic particles; Organic particles; Thickeners; Lubricants; Infrared absorbers; Dyes; Various known additives such as pigments may be used as other additives. .

(Low refractive index layer)
The low refractive index layer also preferably contains a water-soluble resin. In addition, metal oxide particles, a curing agent, a surfactant, and other additives may be included as necessary. The water-soluble resin and metal oxide particles contained in the low refractive index layer are hereinafter referred to as “second water-soluble resin” and “second metal oxide particles” for convenience.

(1) Second water-soluble resin As the second water-soluble resin, the same one as the first water-soluble resin can be used.

At this time, when the high refractive index layer and the low refractive index layer both use a polyvinyl alcohol resin as the first water-soluble resin and the second water-soluble resin, the polyvinyl alcohol resins having different saponification degrees are used. Is preferably used. Thereby, mixing of the interface is suppressed, the reflectance (for example, infrared reflectance (infrared shielding rate)) becomes better, and haze can be lowered. In the present specification, “degree of saponification” means the ratio of hydroxy groups to the total number of acetyloxy groups (derived from the starting vinyl acetate) and hydroxy groups in the polyvinyl alcohol resin.

The content of the second water-soluble resin is preferably 3 to 60% by mass and more preferably 10 to 45% by mass with respect to 100% by mass of the solid content of the low refractive index layer.

(2) Second metal oxide particles The second metal oxide particles are not particularly limited, but it is preferable to use silica (silicon dioxide) such as synthetic amorphous silica or colloidal silica, and acidic colloidal silica sol. It is more preferable to use Further, from the viewpoint of further reducing the refractive index, hollow fine particles having pores inside the particles can be used as the second metal oxide particles, and it is particularly preferable to use hollow fine particles of silica (silicon dioxide). .

The surface of the colloidal silica may be cation-modified, or may be treated with Al, Ca, Mg, Ba or the like.

The second metal oxide particles may be surface-coated with a surface coating component.

The second metal oxide particles (preferably silicon dioxide) contained in the low refractive index layer of the present invention preferably have an average particle diameter (number average; diameter) of 3 to 100 nm, preferably 3 to 50 nm. It is more preferable. In the present specification, the “average particle diameter (number average; diameter)” of the metal oxide particles refers to 1,000 particles observed by an electron microscope on the particles themselves or on the cross section or surface of the refractive index layer. The particle diameter of any of the particles is measured and determined as a simple average value (number average). Here, the particle diameter of each particle is expressed by a diameter assuming a circle equal to the projected area.

The content of the second metal oxide particles in the low refractive index layer is preferably 0.1 to 70% by mass, and preferably 30 to 70% by mass with respect to 100% by mass of the total solid content of the low refractive index layer. More preferred is 45 to 65% by mass.

The above-described second metal oxide may be used alone or in combination of two or more from the viewpoint of adjusting the refractive index.

Curing Agent, Surfactant, and Other Additives As the curing agent, surfactant, and other additives, the same materials as those for the high refractive index layer can be used, and the description thereof is omitted here.

(Water-dispersible hydrophobic resin-containing layer)
As described above, the optical reflective film of the present invention is a water in which at least one of the high refractive index layer and the low refractive index layer constituting the dielectric multilayer film contains a water-soluble resin and a water-dispersible hydrophobic resin. It is a dispersible hydrophobic resin-containing layer, and contains 5 to 55% by mass (solid content mass) of the water-dispersible hydrophobic resin with respect to the total mass (solid content mass) of the water-dispersible hydrophobic resin-containing layer.

The water-dispersible hydrophobic resin-containing layer may be a high-refractive index layer or a low-refractive index layer as long as it includes a water-soluble resin and a predetermined amount of the water-dispersible hydrophobic resin. The water-dispersible hydrophobic resin-containing layer has the same configuration as the above-described high-refractive index layer and low-refractive index layer except that it contains a predetermined amount of a water-dispersible hydrophobic resin described later. Can be done. Since water-dispersible hydrophobic resins generally have a low refractive index (about 1.5), if unfused water-dispersible hydrophobic resin remains, haze increases depending on the refractive index of the high refractive index layer. Because of concern, the water-dispersible hydrophobic resin-containing layer is preferably a low refractive index layer.

In the optical reflective film of the present invention, at least one of the high refractive index layer and the low refractive index layer constituting the dielectric multilayer film may be a water-dispersible hydrophobic resin-containing layer. The lowermost layer in contact with the material or the uppermost layer on the side opposite to the substrate is a water-dispersible hydrophobic resin-containing layer. More preferably, all the low refractive index layers including the lowermost layer and the uppermost layer are water-dispersible hydrophobic resin-containing layers.

Water-dispersible hydrophobic resin The water-dispersible hydrophobic resin applied to the present invention is formed by fusing a hydrophobic polymer dispersed in an aqueous solvent when forming the refractive index layer in the optical reflective film manufacturing process. Resin.

The water-dispersible hydrophobic resin can be an emulsion resin. Emulsion resin is a resin in which fine, for example, resin particles having an average particle size of 2.0 μm or less are dispersed in an emulsion in an aqueous medium, and an oil-soluble monomer is used as a polymer dispersant or the like. It can be obtained by emulsion polymerization using a dispersant.

Oil-soluble monomers that can be used are not particularly limited, but ethylene, propylene, butadiene, vinyl acetate and its partial hydrolyzate, vinyl ether, acrylic acid and its esters, methacrylic acid and its esters, acrylamide and its derivatives, Methacrylamide and derivatives thereof, styrene, divinylbenzene, vinyl chloride, vinylidene chloride, maleic acid, vinyl pyrrolidone, 1,6-hexamethylene diisocyanate and other diisocyanates, polyisocyanates, diols, polyols, dicarboxylic acids, etc. It is done.

The dispersant that can be used is not particularly limited. For example, in addition to a low-molecular dispersant such as alkyl sulfonate, alkyl benzene sulfonate, diethylamine, ethylenediamine, and quaternary ammonium salt, polyoxyethylene nonyl is used. Examples thereof include polymer dispersants such as phenyl ether, polyethylene ethylene laurate, hydroxyethyl cellulose, and polyvinylpyrrolidone.

Examples of the resin to be emulsion-polymerized include acrylic resin, styrene-butadiene resin, ethylene-vinyl acetate resin, urethane resin, phenol resin, and acrylate resin.

As the emulsion resin, commercially available products may be used. For example, mobile 718A, 710A, 731A, LDM7582, 5450, 6960 (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), Superflex (registered trademark) 150, 170, 300, 500M (Daiichi Kogyo Seiyaku Co., Ltd.), Adekabon titer HUX-232, HUX-380, HUX-386, HUX-830, HUX-895 (manufactured by ADEKA Corporation), AE-116, AE-120A, AE-200A, AE-336B, AE-981A, AE-986B (manufactured by E-Tech Co., Ltd.), ETERNACOLL UW-1005E, UW-5002, UW-5034E, UE-5502 (manufactured by Ube Industries, Ltd.), and Acrito UW- 309, UW-319SX, W-520 (Taisei Fine Chemical Co., Ltd.), and the like.

As the emulsion resin, any of an anionic emulsion resin, a cationic emulsion resin, and a nonionic emulsion resin can be used. In the water-dispersible hydrophobic resin-containing layer in the optical reflective film of the present invention, an anionic emulsion resin is used. , And preferably used in combination with an anionic surfactant.

By adding an anionic emulsion resin to a coating solution in which inorganic particles such as metal oxide particles, a water-soluble resin, and a surfactant are dispersed in an aqueous solvent, and using an anionic surfactant as the surfactant. It is considered that the structural viscosity of the coating liquid is stabilized, the dispersion state is improved, and the increase in viscosity is suppressed. As a result, coating failure, particularly streaky coating failure, can be dramatically improved and product yields can be greatly increased.

Here, as the anionic emulsion resin, an anionic urethane emulsion resin, an anionic acrylic emulsion resin, an anionic styrene-acrylic copolymer emulsion resin, or the like can be preferably used. As the anionic surfactant, the same ones as described above can be used.

The particle diameter of the emulsion resin is not particularly limited, but the average particle diameter is preferably 1 to 100 nm, and more preferably 5 to 60 nm. When emulsion resin has the said average particle diameter, the haze of the optical reflection film obtained can be reduced and transparency can improve. The average particle diameter of the emulsion resin can be measured by a dynamic light scattering method.

The refractive index of the emulsion resin is not particularly limited, but is preferably 1.3 to 1.7, more preferably 1.4 to 1.6. If it is the said range, since it becomes close to the refractive index of water-soluble resin, the haze of the optical reflection film obtained can be reduced.

The above-mentioned emulsion resin preferably has a glass transition temperature (Tg) of 20 ° C. or lower, more preferably −30 to 10 ° C., from the viewpoint of enhancing flexibility.

Metal oxide particles The water-dispersible hydrophobic resin-containing layer may contain metal oxide particles. As the metal oxide particles, the same high refractive index layer and low refractive index layer as those described above can be used.

Water-soluble resin The water-dispersible hydrophobic resin-containing layer in the optical reflective film of the present invention contains a water-soluble resin. As the water-soluble resin, those similar to the above-described high refractive index layer and low refractive index layer can be used.

Preferably, the average degree of polymerization of the water-soluble resin in the water-dispersible hydrophobic resin-containing layer is 1500 to 6000, more preferably 4000 to 6000. The average degree of polymerization of the water-soluble resin in the water-dispersible hydrophobic resin-containing layer is more preferably 4000 to 5000, and still more preferably 4500 to 5000. If the average degree of polymerization of the water-soluble resin is 1500 or more, it is possible to suppress the occurrence of haze due to diffusion of the water-soluble resin even when applied by the simultaneous multilayer coating method. In addition, when the average degree of polymerization of the water-soluble resin is 6000 or less, the viscosity of the coating solution does not become too high, which is suitable for the production of a dielectric multilayer film by coating. In the case of having a plurality of water-dispersible hydrophobic resin-containing layers, the average degree of polymerization of the water-soluble resin in at least one water-dispersible hydrophobic resin-containing layer is preferably in the above range, and all water-dispersible hydrophobic properties The average degree of polymerization of the water-soluble resin in the resin-containing layer is more preferably in the above range.

The water-soluble resin in the water-dispersible hydrophobic resin-containing layer is preferably a polyvinyl alcohol resin. Thereby, the dispersibility of the water-dispersible hydrophobic resin is stabilized, and an increase in haze can be suppressed. The saponification degree of the polyvinyl alcohol-based resin is, for example, 70 to 99.5 mol%, and is preferably 80 to 95 mol%, more preferably 85 to 90 mol% from the viewpoint of further suppressing haze. . The average degree of polymerization of the water-soluble resin is the viscosity average degree of polymerization, and the average degree of polymerization of the polyvinyl alcohol-based resin can be measured according to Japanese Industrial Standard JIS K6726: 1994.

Furthermore, in a preferred embodiment of the present invention, among the refractive index layers constituting the dielectric multilayer film, the uppermost layer opposite to the side in contact with the substrate is a water-dispersible hydrophobic resin-containing layer. More preferably, at this time, the average degree of polymerization of the water-soluble resin in the water-dispersible hydrophobic resin-containing layer is 4000 to 6000. The average degree of polymerization of the water-soluble resin in the water-dispersible hydrophobic resin-containing layer is more preferably 4000 to 5000, and still more preferably 4500 to 5000. At this time, if the water-dispersible hydrophobic resin-containing layer contains an anionic emulsion resin and an anionic surfactant, the effects of the present invention can be obtained more remarkably.

As described above, in the optical reflective film of the present invention, at least one of the high refractive index layer and the low refractive index layer constituting the dielectric multilayer film may be a water-dispersible hydrophobic resin-containing layer. When the uppermost layer of the dielectric multilayer film is used as an optical reflector by being bonded to a substrate such as glass through an adhesive layer, for example, when the layer expands or contracts due to adsorption or desorption of moisture in the environment, The stress accompanying it tends to concentrate. Therefore, disposing a water-dispersible hydrophobic resin-containing layer that can suppress the adsorption and desorption of moisture in the environment as the uppermost layer is effective in improving the weather resistance of the optical reflective film.

When a dielectric multilayer film is produced by applying a coating solution containing a water-soluble resin, the average polymerization degree of the water-soluble resin is, for example, 1500 or more, preferably 4000 or more, when it is applied by the simultaneous multilayer coating method. Even if it exists, it can suppress that water-soluble resin diffuses and a haze generate | occur | produces. In addition, when the average degree of polymerization of the water-soluble resin is 6000 or less, the viscosity of the coating solution does not become too high, which is suitable for the production of a dielectric multilayer film by coating. More preferably, the average polymerization degree of the water-soluble resin is 4000 to 5000, and further preferably 4500 to 5000.

In a further preferred embodiment of the present invention, the lowermost layer in contact with the substrate is a water-dispersible hydrophobic resin-containing layer among the refractive index layers constituting the dielectric multilayer film. The lowermost layer of the dielectric multilayer film is a layer in which the stress associated with the expansion and contraction of the layer due to the adsorption and desorption of moisture in the environment compared to the inner layer tends to concentrate. A water-dispersible hydrophobic resin-containing layer is preferable. More preferably, both the uppermost layer and the lowermost layer are water-dispersible hydrophobic resin-containing layers. At this time, if the water-dispersible hydrophobic resin-containing layer contains an anionic emulsion resin and an anionic surfactant, the effects of the present invention can be obtained more remarkably.

In a preferred embodiment of the present invention, the uppermost layer and the lowermost layer of the dielectric multilayer film are low refractive index layers, and all the low refractive index layers are water-dispersible hydrophobic resin-containing layers. In this way, in a dielectric multilayer film using a water-soluble resin, moisture adsorption and desorption associated with fluctuations in the amount of moisture in the environment can be further reduced. The occurrence of cracks can be further reduced. At this time, if the average degree of polymerization of the water-soluble resin in the water-dispersible hydrophobic resin-containing layer is 4000 to 6000, the haze increases even when all the low-refractive index layers contain the water-dispersible hydrophobic resin. Is unlikely to occur.

The thickness of the water-dispersible hydrophobic resin-containing layer is not particularly limited, but when the water-dispersible hydrophobic resin-containing layer is a high refractive index layer, the thickness per layer may be 20 to 800 nm. Preferably, it is 50 to 500 nm. When the water-dispersible hydrophobic resin-containing layer is a low refractive index layer, the thickness per layer is preferably 20 to 800 nm, and more preferably 50 to 500 nm.

[optical properties]
When the optical reflective film according to the present invention is an infrared shielding film that reflects infrared light, it is possible to design a large difference in refractive index between the low refractive index layer and the high refractive index layer with a small number of layers. It is preferable from the viewpoint that the infrared reflectance can be increased. In this embodiment, in at least one of the laminated units composed of the low refractive index layer and the high refractive index layer, the difference in refractive index between the adjacent low refractive index layer and high refractive index layer may be 0.1 or more. Preferably, it is 0.3 or more, more preferably 0.35 or more, and particularly preferably 0.4 or more. In the case of having a plurality of laminated bodies of high refractive index layers and low refractive index layers, it is preferable that the refractive index difference between the high refractive index layer and the low refractive index layer in all the laminated bodies is within the above-mentioned preferable range. However, even in this case, the refractive index layers constituting the uppermost layer and the lowermost layer of the dielectric multilayer film may have a configuration outside the above preferred range.

As an optical characteristic of the optical reflection film of this embodiment, the transmittance in the visible light region shown in JIS R3106-1998 is preferably 50% or more, more preferably 75% or more, and further preferably 85% or more. is there. In addition, it is preferable that the region having a wavelength of 900 nm to 1400 nm has a region with a reflectance exceeding 50%.

From the above viewpoint, the number of refractive index layers of the dielectric multilayer film (total number of high refractive index layers and low refractive index layers) is, for example, 6 to 500 layers, and 6 to 300 layers. Is preferred. In particular, when prepared by a wet film forming method, 6 to 50 layers are preferable, 8 to 40 layers are more preferable, 9 to 30 layers are further preferable, and 11 to 31 layers are preferable. It is particularly preferred. It is preferable that the number of refractive index layers of the dielectric multilayer film is in the above range because excellent heat shielding performance and transparency, suppression of film peeling and cracking, and the like can be realized. When the dielectric multilayer film has a plurality of high refractive index layers and / or low refractive index layers, each high refractive index layer and / or each low refractive index layer is the same, but different. It may be a thing.

The thickness per layer of the high refractive index layer is preferably 20 to 800 nm, and more preferably 50 to 500 nm. Further, the thickness per layer of the low refractive index layer is preferably 20 to 800 nm, and more preferably 50 to 500 nm.

Here, when measuring the thickness per layer, the composition may change continuously without having a clear interface at the boundary between the high refractive index layer and the low refractive index layer. In such an interface region where the composition changes continuously, when the maximum refractive index−the minimum refractive index = Δn, the point of the minimum refractive index + Δn / 2 between the two layers is regarded as the layer interface.

When the high refractive index layer and the low refractive index layer contain metal oxide particles, the above composition can be observed from the concentration profile of the metal oxide particles. The metal oxide concentration profile is formed by etching from the surface to the depth direction using a sputtering method, and using an XPS surface analyzer, sputtering is performed at a rate of 0.5 nm / min, with the outermost surface being 0 nm. It can be seen by measuring the ratio. Further, the laminated film may be cut and the cut surface may be confirmed by measuring the atomic composition ratio with an XPS surface analyzer.

The XPS surface analyzer is not particularly limited, and any model can be used. As the XPS surface analyzer, for example, ESCALAB-200R manufactured by VG Scientific, Inc. can be used. Mg is used for the X-ray anode, and measurement is performed at an output of 600 W (acceleration voltage: 15 kV, emission current: 40 mA).

[Adhesive layer]
The optical reflective film according to the present invention may have an adhesive layer. This pressure-sensitive adhesive layer is usually provided on the surface of the dielectric multilayer film opposite to the substrate, and a known release paper or separator may be further provided. The configuration of the adhesive layer is not particularly limited, and for example, any of a dry laminating agent, a wet laminating agent, an adhesive, a heat seal agent, a hot melt agent, and the like is used.

As the pressure-sensitive adhesive, for example, a polyester-based pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, a polyvinyl acetate-based pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, nitrile rubber, or the like is used.

When the optical reflective film of the present invention is bonded to a window glass, water is sprayed on the window, and a method of applying the adhesive layer of the optical reflective film to the wet glass surface, the so-called water pasting method is repositioned, repositioned, etc. From the viewpoint of, it is preferably used. For this reason, an acrylic pressure-sensitive adhesive that has a weak adhesive force in the presence of water is preferably used.

The acrylic pressure-sensitive adhesive used may be either solvent-based or emulsion-based, but is preferably a solvent-based pressure-sensitive adhesive because it is easy to increase the adhesive strength and the like, and among them, those obtained by solution polymerization are preferable. Examples of the raw material for producing such a solvent-based acrylic pressure-sensitive adhesive by solution polymerization include, for example, acrylic acid esters such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and acryl acrylate as main monomers serving as a skeleton, As a comonomer to improve cohesive strength, vinyl acetate, acrylonitrile, styrene, methyl methacrylate, etc., to further promote crosslinking, to give stable adhesive strength, and to maintain a certain level of adhesive strength even in the presence of water Examples of the functional group-containing monomer include methacrylic acid, acrylic acid, itaconic acid, hydroxyethyl methacrylate, and glycidyl methacrylate. Since the adhesive layer requires a particularly high tack property as the main polymer, those having a low glass transition temperature (Tg) such as butyl acrylate are particularly useful.

Examples of commercially available acrylic pressure-sensitive adhesives include, for example, Coponil (registered trademark) series (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.).

This adhesive layer contains additives such as stabilizers, surfactants, UV absorbers, flame retardants, antistatic agents, antioxidants, thermal stabilizers, lubricants, fillers, coloring, adhesion modifiers, etc. It can also be made. In particular, when used for window sticking, the addition of an ultraviolet absorber is effective in order to suppress deterioration of the optical reflection film due to ultraviolet rays.

The method for applying the adhesive is not particularly limited, and any known method can be used, for example, bar coating method, die coater method, comma coating method, gravure roll coater method, blade coater method, spray coater method, An air knife coating method, a dip coating method, a transfer method, and the like are preferably mentioned, and they can be used alone or in combination. However, it is preferable to carry out a roll method continuously from the viewpoint of economy and productivity. These can be appropriately formed into a solution in a solvent capable of dissolving the pressure-sensitive adhesive, or can be applied using a dispersed coating solution, and known solvents can be used.

In addition, the thickness of the adhesive layer is preferably in the range of usually about 1 to 100 μm from the viewpoint of the adhesive effect, the drying speed and the like.

The adhesive strength is preferably 2 to 30 N / 25 mm, more preferably 4 to 20 N / 25 mm, as measured by a 180 ° peel test described in JIS K6854.

The adhesive layer may be formed directly on the dielectric multilayer film by the previous coating method. Alternatively, the adhesive layer may be applied to a release film and dried, and then the dielectric multilayer film is bonded. The adhesive may be transferred. The drying temperature at this time is preferably such that the residual solvent is reduced as much as possible. For this purpose, the drying temperature and time are not specified, but a drying time of 10 seconds to 5 minutes is preferably provided at a temperature of 50 to 150 ° C. Is good.

[Hard coat layer]
In the optical reflective film of the present invention, a hard coat layer containing a resin that is cured by heat, ultraviolet rays, or the like may be laminated as a surface protective layer for improving the scratch resistance. For example, a preferable example is a form in which a dielectric multilayer film and an adhesive layer are laminated in this order on the substrate surface, and a hard coat layer is coated on the substrate surface on the side opposite to the side where these layers are laminated. Can be mentioned.

Examples of the curable resin used in the hard coat layer include a thermosetting resin and an ultraviolet curable resin. However, an ultraviolet curable resin is preferable because it is easy to mold, and among them, those having a pencil hardness of at least 2H. More preferred. Such curable resins can be used alone or in combination of two or more.

Examples of the ultraviolet curable resin include (meth) acrylate, urethane acrylate, polyester acrylate, epoxy acrylate, epoxy resin, and oxetane resin, and these can also be used as a solvent-free resin composition.

When using the ultraviolet curable resin, it is preferable to add a photopolymerization initiator to accelerate curing.

Photoinitiators include acetophenones, benzophenones, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, thiuram compounds, fluoroamine compounds Etc. are used. Specific examples of the photopolymerization initiator include 2,2′-diethoxyacetophenone, p-dimethylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 1-hydroxydimethylphenyl ketone, 2-methyl-4′-methylthio-2-mori. Acetophenones such as holinopropiophenone and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone 1, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyldimethylletal, etc. Benzoin, benzophenone, 2,4'-dichlorobenzophenone, 4,4'-dichlorobenzophenone, benzophenones such as p-chlorobenzophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, an Rakinon such, there is such as thioxanthones. These photopolymerization initiators may be used alone, in combination of two or more, or in a eutectic mixture. In particular, acetophenones are preferably used from the viewpoints of stability of the curable composition and polymerization reactivity.

Commercially available products may be used as such photopolymerization initiators, and preferred examples include Irgacure (registered trademark) 819, 184, 907, 651 manufactured by BASF Japan Ltd., for example.

The thickness of the hard coat layer is preferably from 0.1 to 50 μm, more preferably from 1 to 20 μm, from the viewpoints of improving the hard coat properties and improving the transparency of the optical reflective film.

The method for forming the hard coat layer is not particularly limited. For example, after preparing a hard coat layer coating solution containing the above components, the coating solution is applied with a wire bar or the like, and the coating solution is cured with heat and / or UV. And a method of forming a hard coat layer.

[Other layers]
The optical reflective film according to the present invention may have a layer (other layers) other than the layers described above. For example, an intermediate layer can be provided as the other layer. Here, the “intermediate layer” means a layer between the base material and the dielectric multilayer film, or a layer between the base material and the hard coat layer. Examples of the constituent material of the intermediate layer include polyester resin, polyvinyl alcohol resin, polyvinyl acetate resin, polyvinyl acetal resin, acrylic resin, urethane resin, and the like. Any of them may be used as long as they are satisfied. The glass transition temperature (Tg) of the intermediate layer is preferably 30 to 120 ° C. because sufficient weather resistance can be obtained, and more preferably in the range of 30 to 90 ° C.

[Method for producing optical reflection film]
There is no restriction | limiting in particular about the manufacturing method of the optical reflection film of this invention, At least 1 unit comprised from a high refractive index layer and a low refractive index layer is formed on a base material, and a high refractive index layer or a low refractive index is formed. Any method can be used as long as at least one of the layers can be the above-described water-dispersible hydrophobic resin-containing layer.

Specifically, it is preferable to form a laminate (dielectric multilayer film) by alternately applying and drying a high refractive index layer and a low refractive index layer. Specific examples include the following: (1) A high refractive index layer coating solution is applied onto a substrate and dried to form a high refractive index layer, and then a low refractive index layer coating solution is applied and dried. Forming a low refractive index layer and forming an optical reflective film; (2) applying a low refractive index layer coating solution on a substrate and drying to form a low refractive index layer; A method of forming a high refractive index layer by applying a layer coating solution and drying to form an optical reflective film; (3) alternating a high refractive index layer coating solution and a low refractive index layer coating solution on a substrate A method of forming an optical reflective film comprising a high refractive index layer and a low refractive index layer; (4) a high refractive index layer coating solution and a low refractive index layer; A method of forming an optical reflective film including a high refractive index layer and a low refractive index layer by simultaneously applying a coating layer with a coating solution and drying;Among these, the method (4), which is a simpler manufacturing process, is preferable. That is, it is preferable that the method for producing an optical reflective film of the present invention includes laminating the high refractive index layer and the low refractive index layer by a simultaneous multilayer coating method.

When simultaneous multilayer coating is applied, the layers are stacked in an undried liquid state, so inter-layer mixing is more likely to occur. However, when the water-soluble resin is a polyvinyl alcohol resin, the saponification degree of the polyvinyl alcohol resin contained in the high refractive index layer is different from the saponification degree of the polyvinyl alcohol resin contained in the low refractive index layer. It is known that the compatibility of polyvinyl alcohol resins having different degrees is low. Therefore, even when the high refractive index layer and the low refractive index layer are stacked in an undried liquid state, even if the layers are mixed somewhat, if the solvent water is volatilized and concentrated in the drying process, the saponification degree Polyvinyl alcohol resins having different values cause phase separation, and a force to minimize the area of the interface of each layer is exerted, so interphase mixing is suppressed and interface disturbance is reduced. Therefore, an optical reflection film having excellent light reflection characteristics in a desired wavelength region and less haze can be obtained.

Examples of the coating method include a roll coating method, a rod bar coating method, an air knife coating method, a spray coating method, a curtain coating method, or US Pat. Nos. 2,761,419 and 2,761,791. A slide bead coating method using an hopper, an extrusion coating method, or the like is preferably used.

The solvent for preparing the high refractive index layer coating solution and the low refractive index layer coating solution is not particularly limited, but water, an organic solvent, or a mixed solvent thereof is preferable. In the present invention, an aqueous solvent can be used in order to use a water-soluble resin. Compared to the case where an organic solvent is used, the aqueous solvent does not require a large-scale production facility, so that it is preferable in terms of productivity and also in terms of environmental conservation.

Examples of the organic solvent include alcohols such as methanol, ethanol, 2-propanol and 1-butanol, esters such as ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate, diethyl ether, Examples thereof include ethers such as propylene glycol monomethyl ether and ethylene glycol monoethyl ether, amides such as dimethylformamide and N-methylpyrrolidone, and ketones such as acetone, methyl ethyl ketone, acetylacetone and cyclohexanone. These organic solvents may be used alone or in combination of two or more. From the viewpoint of environment and simplicity of operation, the solvent of the coating solution is preferably an aqueous solvent, more preferably water or a mixed solvent of water and methanol, ethanol, or ethyl acetate, and water is particularly preferable.

When using a mixed solvent of water and a small amount of an organic solvent, the content of water in the mixed solvent is preferably 80 to 99.9% by mass, based on 100% by mass of the entire mixed solvent, and preferably 90 to 99%. More preferably, it is 5 mass%. Here, by setting it to 80% by mass or more, volume fluctuation due to solvent volatilization can be reduced, handling is improved, and by setting it to 99.9% by mass or less, homogeneity at the time of liquid addition is increased and stable. This is because the obtained liquid properties can be obtained.

The concentration of the water-soluble resin in the high refractive index layer coating solution is preferably 0.5 to 10% by mass. The concentration of the metal oxide particles in the high refractive index layer coating solution is preferably 1 to 50% by mass.

The concentration of the water-soluble resin in the low refractive index layer coating solution is preferably 0.5 to 10% by mass. The concentration of the metal oxide particles in the low refractive index layer coating solution is preferably 1 to 50% by mass.

The method for preparing the high refractive index layer coating liquid and the low refractive index layer coating liquid is not particularly limited. It is done. At this time, the order of addition of the respective components is not particularly limited, and the respective components may be sequentially added and mixed while stirring, or may be added and mixed at one time while stirring.

When at least one of the high refractive index layers is a water-dispersible hydrophobic resin-containing layer, the water-dispersible hydrophobic resin is added to the above-described high refractive index layer coating solution with a predetermined solid content concentration. A water-dispersible hydrophobic resin-containing layer coating solution (water-dispersible hydrophobic resin-containing high refractive index layer coating solution) may be prepared so as to fall within the range. A water-dispersible hydrophobic resin-containing layer that functions as a high refractive index layer can be obtained by applying and drying the water-dispersible hydrophobic resin-containing layer coating solution.

Similarly, when at least one of the low refractive index layers is a water-dispersible hydrophobic resin-containing layer, the water-dispersible hydrophobic resin is added to the final solid concentration in the low refractive index layer coating liquid as described above. Is added so as to be within a predetermined range to prepare a water-dispersible hydrophobic resin-containing layer coating solution (water-dispersible hydrophobic resin-containing low refractive index layer coating solution). A water-dispersible hydrophobic resin-containing layer that functions as a low refractive index layer can be obtained by applying and drying the water-dispersible hydrophobic resin-containing layer coating solution.

The concentration of the water-dispersible hydrophobic resin in the water-dispersible hydrophobic resin-containing layer coating solution is not particularly limited, but the content of the water-dispersible hydrophobic resin in the water-dispersible hydrophobic resin-containing layer (solid content) ) Within the above range.

As described above, a preferred form of the optical reflective film of the present invention contains an anionic emulsion resin and an anionic surfactant in a water-dispersible hydrophobic resin-containing layer. Therefore, preferably, the optical reflective film of the present invention comprises a step of preparing a coating solution by dissolving or dispersing a water-soluble resin, an anionic surfactant, and an anionic emulsion resin in an aqueous solvent, and applying the coating solution. Thereby forming the water-dispersible hydrophobic resin-containing layer.

When using the slide bead coating method, the temperature of the high refractive index layer coating solution and the low refractive index layer coating solution during simultaneous multilayer coating is preferably a temperature range of 25 to 60 ° C., and a temperature range of 30 to 45 ° C. Is more preferable. When the curtain coating method is used, a temperature range of 25 to 60 ° C. is preferable, and a temperature range of 30 to 45 ° C. is more preferable.

The viscosity of the high refractive index layer coating solution and the low refractive index layer coating solution during simultaneous multilayer coating is not particularly limited. However, when the slide bead coating method is used, the preferable temperature range of the coating liquid is preferably 5 to 160 mPa · s, more preferably 60 to 140 mPa · s. When the curtain coating method is used, the preferable temperature range of the coating solution is preferably 5 to 1200 mPa · s, more preferably 25 to 500 mPa · s. If it is the range of such a viscosity, simultaneous multilayer coating can be performed efficiently.

Further, the viscosity at 15 ° C. of the coating solution is preferably 100 mPa · s or more, more preferably 100 to 30,000 mPa · s, and further preferably 2,500 to 30,000 mPa · s.

The conditions for the coating and drying method are not particularly limited. For example, in the case of the sequential coating method, first, either one of the high refractive index layer coating solution and the low refractive index layer coating solution heated to 30 to 60 ° C. is used. After coating and drying on a substrate to form a layer, the other coating solution is coated on this layer and dried to form a laminated film precursor (unit). Next, the number of units necessary for expressing the desired optical reflection performance is sequentially applied and dried by the above method to obtain a laminated film precursor. When drying, it is preferable to dry the formed coating film at 30 ° C. or higher. For example, drying is preferably performed in the range of a wet bulb temperature of 5 to 50 ° C. and a film surface temperature of 5 to 100 ° C. (preferably 10 to 50 ° C.). For example, hot air of 40 to 60 ° C. is blown for 1 to 5 seconds. dry. As a drying method, warm air drying, infrared drying, and microwave drying are used. Further, drying in a multi-stage process is preferable to drying in a single process, and it is more preferable to set the temperature of the constant rate drying section <the temperature of the rate-decreasing drying section. In this case, the temperature range of the constant rate drying section is preferably 30 to 60 ° C., and the temperature range of the decreasing rate drying section is preferably 50 to 100 ° C.

In addition, the conditions of the coating and drying method when performing simultaneous multilayer coating are as follows. After the simultaneous multilayer coating of the liquid and the low refractive index layer coating liquid, the temperature of the formed coating film is preferably cooled (set) preferably to 1 to 15 ° C. and then dried at 10 ° C. or higher. More preferable drying conditions are a wet bulb temperature of 5 to 50 ° C. and a film surface temperature of 10 to 50 ° C. For example, it is dried by blowing warm air of 40 to 80 ° C. for 1 to 5 seconds. Moreover, as a cooling method immediately after application | coating, it is preferable to carry out by a horizontal set system from a viewpoint of the uniformity improvement of the formed coating film.

Here, the set means that the viscosity of the coating composition is increased by means such as lowering the temperature by applying cold air or the like to the coating film, the fluidity of the substances in each layer and in each layer is reduced, or the gel It means the process of converting. A state in which the cold air is applied to the coating film from the surface and the finger is pressed against the surface of the coating film is defined as a set completion state.

The time (setting time) from the time of application until the setting is completed by applying cold air is preferably within 5 minutes, and more preferably within 2 minutes. Further, the lower limit time is not particularly limited, but it is preferable to take 45 seconds or more. If the intermediate layer between the high-refractive index layer and the low-refractive index layer is highly elastic, the setting step may not be provided.

The set time is adjusted by adjusting the concentration of polyvinyl alcohol resin and metal oxide particles, and adding other components such as gelatin, pectin, agar, carrageenan, gellan gum and other known gelling agents. It can be adjusted by doing.

The temperature of the cold air is preferably 0 to 25 ° C, more preferably 5 to 10 ° C. The time for which the coating film is exposed to cold air is preferably 10 to 360 seconds, more preferably 10 to 300 seconds, and further preferably 10 to 120 seconds, although it depends on the transport speed of the coating film.

The coating thickness of the high refractive index layer coating solution and the low refractive index layer coating solution may be applied so as to have a preferable dry thickness as described above.

<Optical reflector>
The optical reflective film of the present invention can be applied to a wide range of fields. Therefore, one embodiment of the present invention is an optical reflector in which the above-described optical reflective film is provided on at least one surface of a substrate. For example, film for window pasting such as heat ray reflecting film that gives heat ray reflection effect, film for agricultural greenhouses, etc. Etc., mainly for the purpose of improving the weather resistance. In particular, the optical reflective film according to the present invention is suitable for a member that is bonded to a substrate such as glass or a glass substitute resin through the above-mentioned adhesive layer.

Specific examples of the substrate include, for example, glass, polycarbonate resin, polysulfone resin, acrylic resin, polyolefin resin, polyether resin, polyester resin, polyamide resin, polysulfide resin, unsaturated polyester resin, epoxy resin, melamine resin, and phenol. Examples thereof include resins, diallyl phthalate resins, polyimide resins, urethane resins, polyvinyl acetate resins, polyvinyl alcohol resins, styrene resins, vinyl chloride resins, metal plates, and ceramics. The type of resin may be any of a thermoplastic resin, a thermosetting resin, and an ionizing radiation curable resin, and two or more of these may be used in combination. The substrate can be produced by a known method such as extrusion molding, calendar molding, injection molding, hollow molding, compression molding or the like. The thickness of the substrate is not particularly limited, but is usually 0.1 mm to 5 cm.

The adhesive layer that bonds the optical reflection film and the substrate is preferably installed so that the optical reflection film is on the sunlight (heat ray) incident surface side when bonded to a window glass or the like. Further, when the optical reflection film is sandwiched between the window glass and the base material, it can be sealed from ambient gas such as moisture, which is preferable for durability. Even if the optical reflective film of the present invention is installed outdoors or on the outside of a vehicle (for external application), it is preferable because of environmental durability.

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "mass part" or "mass%" is represented. Unless otherwise specified, each operation is performed at room temperature (25 ° C.).

≪Preparation of optical reflective film≫
(Example 1)
<Preparation of high refractive index layer coating solution 1>
A high refractive index layer coating solution 1 was prepared according to the following procedure.

(Preparation of silica-attached titanium dioxide sol)
First, a silica-attached titanium dioxide sol containing rutile titanium dioxide was prepared as follows.

After adding 2 parts by mass of pure water to 0.5 parts by mass of 15.0% by mass titanium oxide sol (SRD-W, volume average particle size: 5 nm, rutile titanium dioxide particles, manufactured by Sakai Chemical Industry Co., Ltd.), 90 ° C. Heated. Next, 0.5 parts by mass of an aqueous silicic acid solution (sodium silicate 4 (manufactured by Nippon Chemical Industry Co., Ltd.) diluted with pure water so that the SiO ₂ concentration becomes 0.5 mass%) was gradually added. Then, heat treatment was performed at 175 ° C. for 18 hours in an autoclave, and after cooling, the resultant was concentrated with an ultrafiltration membrane, thereby attaching SiO ₂ having a solid content concentration of 6% by mass to titanium dioxide on the surface. A titanium dioxide sol (hereinafter, silica-attached titanium dioxide sol) (volume average particle diameter: 9 nm) was obtained.

(Preparation of high refractive index layer coating solution 1)
48 parts by mass of an aqueous citric acid solution (1.92% by mass) is added to 113 parts by mass of the silica-attached titanium dioxide sol (20% by mass) obtained by the above procedure, and polyvinyl alcohol (PVA-117, manufactured by Kuraray Co., Ltd.) is added. , Average polymerization degree 1700, saponification degree: 97.5-99 mol%, 8 mass%) was added and stirred, and finally a 5 mass% aqueous solution of surfactant (Softazoline LSB-R, Kawaken Fine Chemical Co., Ltd.) 0.4 parts by mass) was added to prepare a high refractive index layer coating solution 1.

The refractive index of the film coated with the high refractive index layer coating solution 1 was 1.80. In addition, the measuring method of a refractive index is as follows (hereinafter the same).

<Measurement of single-film refractive index of each layer>
In order to measure the refractive index, a sample in which the high refractive index layer coating solution 1 was applied as a single layer on a substrate was prepared, and this sample was cut into 10 cm × 10 cm, and then the refractive index was determined according to the following method. . Using Hitachi spectrophotometer U-4100 (solid sample measurement system), the surface opposite to the measurement surface (back surface) of each sample is roughened and then light absorption is performed with a black spray. Then, reflection of light on the back surface was prevented, and the reflectance in the visible light region (400 nm to 700 nm) was measured under the condition of 5 ° regular reflection, and the refractive index was obtained from the result.

<Preparation of low refractive index layer coating solution 1>
A 31% by mass acidic colloidal silica 10% by mass aqueous solution (Snowtex (registered trademark) OXS, primary particle size: 5.4 nm, manufactured by Nissan Chemical Industries, Ltd.) is heated to 40 ° C., and a boric acid 3% by mass aqueous solution is heated. 3 parts by weight were added, and 39 parts by weight of a 6% by weight aqueous solution of polyvinyl alcohol (PVA-224, average degree of polymerization: 2400, degree of saponification: 87 to 89% by mole, manufactured by Kuraray Co., Ltd.) A low-refractive-index layer coating solution 1 was prepared by adding 5 parts by weight of a surfactant in an amount of 5% by weight (SOFTAZOLINE LSB-R, manufactured by Kawaken Fine Chemical Co., Ltd.) in this order at 40 ° C.

The refractive index of the film coated with the low refractive index layer coating solution 1 was 1.50.

<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1>
A 13% by mass acidic colloidal silica 10% by mass aqueous solution (Snowtex (registered trademark) OXS, primary particle size: 5.4 nm, manufactured by Nissan Chemical Industries, Ltd.) is heated to 40 ° C., and a boric acid 3% by mass aqueous solution is heated. In addition to 3 parts by mass, as a water-soluble resin, 35 parts by mass of a 6% by weight aqueous solution of polyvinyl alcohol (PVA-224, average polymerization degree: 2400, saponification degree: 87-89 mol%, manufactured by Kuraray Co., Ltd.), 3 parts by mass 6 parts by weight of a water-dispersed urethane resin (Adekabon titer HUX-830, average particle size = 100 nm, manufactured by ADEKA Corporation) and 1 part by weight of a 5% by weight aqueous solution of a nonionic surfactant (Neugen XL-40) And Daiichi Kogyo Seiyaku Co., Ltd.) were added in this order at 40 ° C. to prepare a water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1.

The zeta potential was measured to confirm that the water-dispersed urethane resin was a nonionic resin. The specific measurement method is as follows.

Device: Malvern Zetasizer Nano ZSP
Measurement method: electrophoretic light scattering method Sample preparation: Measured by diluting a water-dispersible hydrophobic resin to 1% by mass%.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1 was 1.50.

<Preparation of optical reflection film 1>
Using a slide hopper coating apparatus capable of coating 19 layers, the above prepared high refractive index layer coating solution 1, low refractive index layer coating solution 1, and water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1 , Respectively, adjusted to 40 ° C. On the polyethylene terephthalate film (Toyobo A4300: double-sided easy adhesion layer) 160 mm wide and 50 μm thick, which is a base material heated to 40 ° C., the lowermost layer and the uppermost layer are low refractive index layers. Except for the layer being a water-dispersible hydrophobic resin-containing low-refractive index layer, each layer is alternately dried with a low-refractive index layer and a water-dispersible hydrophobic resin-containing low-refractive index layer, each having a thickness of 150 nm and a high refractive index. A total of 19 layers were simultaneously applied so that the rate layer was 130 nm in each layer. Immediately after application, cold air of 10 ° C. was blown to set (thickening).

After completion of the setting (thickening), warm air of 60 ° C. was blown and dried to produce the optical reflective film 1 of Example 1 consisting of a total of 19 layers.

The film thickness is measured (confirmed) by cutting the optical reflection film sample and measuring the abundance of the high refractive index material (TiO ₂ ) and the low refractive index material (SiO ₂ ) with the XPS surface analyzer. Thus, it was confirmed that the film thicknesses of the respective layers were ensured.

(Example 2)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 2>
Water dispersible hydrophobicity except that 18 parts by weight of 10% by weight aqueous solution of acidic colloidal silica, 6 parts by weight of 6% by weight aqueous solution of polyvinyl alcohol and 47 parts by weight of 6% by weight aqueous solution of water-dispersed urethane resin are used. In the same manner as the resin-containing low refractive index layer coating solution 1, a water-dispersible hydrophobic resin-containing low refractive index layer coating solution 2 was prepared.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 2 was 1.50.

<Preparation of optical reflection film 2>
In Example 1 (preparation of the optical reflective film 1), the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1 was changed to the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 2 prepared as described above. Except having changed, the optical reflection film 2 was produced like Example 1. FIG.

(Example 3)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 3>
In Example 1 (preparation of coating liquid 1 having a low refractive index layer containing a dispersible hydrophobic resin), 10 mass% aqueous solution of acidic colloidal silica is 19 mass parts, and 6 mass% aqueous solution of polyvinyl alcohol is 38 mass parts, A water-dispersible hydrophobic resin-containing low refractive index layer coating solution 3 was prepared in the same manner as in Example 1 except that the amount of the water-dispersed urethane resin aqueous solution was 18 parts by mass.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 3 was 1.50.

<Preparation of optical reflection film 3>
In Example 1 (preparation of the optical reflective film 1), the water-dispersible hydrophobic resin-containing low-refractive index layer coating solution 1 was changed to the water-dispersible hydrophobic resin-containing low-refractive index layer coating solution 3 prepared as described above. An optical reflective film 3 was produced in the same manner as in Example 1 except that the change was made.

Example 4
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 4>
In Example 1 (Preparation of Dispersible Hydrophobic Resin-Containing Low Refractive Index Layer Coating Liquid 1), 10 mass% aqueous solution of acidic colloidal silica was 19 mass parts, 6 mass% aqueous solution of polyvinyl alcohol was 38 mass parts, water 18 parts by mass of a 6% by mass aqueous solution of dispersed urethane resin, and 1 part by mass of an anionic surfactant of 1 part by mass of a 5% by mass aqueous solution of a nonionic surfactant (Neugen XL-40, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) A water-dispersible hydrophobic resin-containing low refractive index layer coating solution 4 was prepared in the same manner as in Example 1 except that a 5% by mass aqueous solution of the agent (Hitenol NF-08, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was used. .

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 4 was 1.50.

<Preparation of Optical Reflective Film 4>
In Example 1 (preparation of the optical reflective film 1), the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1 was changed to the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 4 prepared as described above. An optical reflective film 4 was produced in the same manner as in Example 1 except that the change was made.

(Example 5)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 5>
In Example 1 (preparation of coating liquid 1 containing a low-refractive index layer containing a dispersible hydrophobic resin), 3 parts by mass of a water-dispersed urethane resin 6% by mass aqueous solution (Adekabon titer HUX-830, average particle size = 100 nm, ADEKA Co., Ltd.) was changed to 3 parts by weight of a water-dispersed acrylic resin 6% by weight aqueous solution (AE-116, average particle size = 80 nm, manufactured by Etec Co., Ltd.), and 5 parts by weight of 1 part by weight of a nonionic surfactant. Other than changing the aqueous solution (Neugen XL-40, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) to 1 part by mass of a 5% by weight aqueous solution of anionic surfactant (Hitenol NF-08, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) In the same manner as in Example 1, a water-dispersible hydrophobic resin-containing low refractive index layer coating solution 5 was prepared.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 5 was 1.50.

The zeta potential was measured to confirm that the water-dispersed acrylic resin was an anionic resin. The specific measurement method is the same as the measurement in the water-dispersed urethane resin.

<Preparation of optical reflection film 5>
In Example 1 (preparation of the optical reflective film 1), the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1 was changed to the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 5 prepared as described above. An optical reflective film 5 was produced in the same manner as in Example 1 except that the change was made.

(Example 6)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 6>
In Example 1 (Preparation of coating liquid 1 having a low refractive index layer containing a dispersible hydrophobic resin), 3 parts by mass of a water-dispersed urethane resin 6% by mass aqueous solution and 3 parts by mass of a water-dispersed acrylic resin 6% by mass aqueous solution (AE) -120A, average particle size = 55 nm, manufactured by Etec Co., Ltd. 1 mass part of a 5% by weight aqueous solution of a nonionic surfactant is converted to 1 part by weight of a 5% by weight aqueous solution of anionic surfactant (Hitenol) A water-dispersible hydrophobic resin-containing low refractive index layer coating solution 6 was prepared in the same manner as in Example 1 except that NF-08 (Daiichi Kogyo Seiyaku Co., Ltd.) was changed.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 6 was 1.50.

<Preparation of optical reflection film 6>
In Example 1 (production of the optical reflective film 1), the water-dispersible hydrophobic resin-containing low-refractive index layer coating solution 1 was changed to the water-dispersible hydrophobic resin-containing low-refractive index layer coating solution 6 prepared as described above. An optical reflective film 6 was produced in the same manner as in Example 1 except that the change was made.

(Example 7)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 7>
In Example 1 (preparation of coating liquid 1 having a low refractive index layer containing a dispersible hydrophobic resin), 6 mass% aqueous solution of acidic colloidal silica is 18 mass parts, 6 mass% aqueous solution of polyvinyl alcohol is 6 mass parts, 3 parts by weight of a water-dispersed urethane resin 6% by weight aqueous solution (Adekabon titer HUX-830, average particle size = 100 nm, manufactured by ADEKA Corporation) 47 parts by weight of a water-dispersed acrylic resin 6% by weight aqueous solution (AE-120A, average) The particle size was changed to 55 nm (manufactured by Etec Co., Ltd.), and 1 part by weight of a 5% by weight aqueous solution of a nonionic surfactant (Neugen XL-40, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to 1 part by weight of an anionic interface. A water-dispersible hydrophobic property was obtained in the same manner as in Example 1 except that the active agent was changed to a 5% by mass aqueous solution (Haitenol NF-08, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). The fat content low refractive index layer coating solution 7 was prepared.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 7 was 1.50.

<Preparation of optical reflection film 7>
In Example 1 (production of the optical reflective film 1), the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1 was used as the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 7 prepared as described above. An optical reflective film 7 was produced in the same manner as in Example 1 except that the change was made.

(Example 8)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 8>
In Example 1 (preparation of coating liquid 1 having a low refractive index layer containing a dispersible hydrophobic resin), 10 mass% aqueous solution of acidic colloidal silica is 19 mass parts, and 6 mass% aqueous solution of polyvinyl alcohol is 38 mass parts, 3 parts by weight of a water-dispersed urethane resin 6% by weight aqueous solution (Adekabon titer HUX-830, average particle size = 100 nm, manufactured by ADEKA Corporation) 18 parts by weight of a water-dispersed acrylic resin 6% by weight aqueous solution (AE-120A, average) The particle size was changed to 55 nm (manufactured by Etec Co., Ltd.), and 1 part by weight of a 5% by weight aqueous solution of a nonionic surfactant (Neugen XL-40, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to 1 part by weight of an anionic interface. A water-dispersible sparseness was obtained in the same manner as in Example 1, except that the active agent was changed to a 5% by mass aqueous solution (Haitenol NF-08, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). Sexual resin containing low refractive index layer coating solution 8 was prepared.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 8 was 1.50.

<Preparation of optical reflection film 8>
In Example 1 (production of the optical reflective film 1), the water-dispersible hydrophobic resin-containing low-refractive index layer coating solution 1 was used as the water-dispersible hydrophobic resin-containing low-refractive index layer coating solution 8 prepared as described above. An optical reflective film 8 was produced in the same manner as in Example 1 except that the change was made.

Example 9
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 9>
In Example 1 (preparation of coating liquid 1 having a low refractive index layer containing a dispersible hydrophobic resin), 10 mass% aqueous solution of acidic colloidal silica is 19 mass parts, and 6 mass% aqueous solution of polyvinyl alcohol is 38 mass parts, 3 parts by weight of a water-dispersed urethane resin 6% by weight aqueous solution (Adekabon titer HUX-830, average particle size = 100 nm, manufactured by ADEKA Corporation) was added 18 parts by weight of a water-dispersed acrylic resin 6% by weight aqueous solution (AE-120A, A water-dispersible hydrophobic resin-containing low refractive index layer coating solution 9 was prepared in the same manner as in Example 1 except that the average particle size was changed to 55 nm (manufactured by Etec Co., Ltd.).

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 9 was 1.50.

<Preparation of optical reflection film 9>
In Example 1 (production of the optical reflective film 1), the water-dispersible hydrophobic resin-containing low-refractive index layer coating solution 1 was used as the water-dispersible hydrophobic resin-containing low-refractive index layer coating solution 9 prepared as described above. An optical reflective film 9 was produced in the same manner as in Example 1 except that the change was made.

(Example 10)
<Preparation of optical reflection film 10>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to water. The dispersion liquid is changed to the hydrophobic resin-containing low refractive index layer coating solution 8, and the 19th layer from the base material side is replaced with the 11th layer from the base material side. Except for this, an optical reflective film 10 was produced in the same manner as in Example 1.

(Example 11)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 10>
In Example 1 (preparation of coating liquid 1 having a low refractive index layer containing a dispersible hydrophobic resin), 19 parts by mass of 10% by weight aqueous solution of acidic colloidal silica was used, and 6% by weight aqueous solution of polyvinyl alcohol (JC -40, average degree of polymerization: 4000, degree of saponification: 99 mol%, manufactured by Nihon Ventures & Poval Co., Ltd.) 38 parts by mass, 3 parts by mass of water-dispersed urethane resin 6% by mass aqueous solution (Adekabon titer HUX- 830, average particle size = 100 nm, manufactured by ADEKA Corporation) was changed to 18 parts by mass of an aqueous dispersion acrylic resin 6% by mass aqueous solution (AE-120A, average particle size = 55 nm, manufactured by Etec Co., Ltd.). A 5% by weight aqueous solution of a nonionic surfactant (Neugen XL-40, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to 1 part by weight of a 5% by weight aqueous solution (c) Tenor NF-08, was changed to Dai-ichi Kogyo Seiyaku Co., Ltd.) in the same manner as in Example 1, a water-dispersible hydrophobic resin containing low refractive index layer coating solution 10 was prepared.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 10 was 1.50.

<Preparation of optical reflection film 11>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to the above. In addition to the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 10 prepared in Step 1, the 19th layer from the substrate side is replaced by the 11th layer from the substrate side, and the water-dispersible hydrophobic resin containing low An optical reflective film 11 was produced in the same manner as in Example 1 except that the refractive index layer was used.

Example 12
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 11>
In the above Example 1 (Preparation of coating liquid 1 for low refractive index layer containing dispersible hydrophobic resin), 19 parts by mass of 10% by weight aqueous solution of acidic colloidal silica and 19% by weight aqueous solution of polyvinyl alcohol (JP) -45, average degree of polymerization: 4500, degree of saponification: 99 mol%, manufactured by Nihon Acetate Bipoval Co., Ltd.) 38 parts by mass, 3 parts by mass of water-dispersed urethane resin 6% by mass aqueous solution (Adekabon titer HUX- 830, average particle size = 100 nm, manufactured by ADEKA Corporation) was changed to 18 parts by mass of an aqueous dispersion acrylic resin 6% by mass aqueous solution (AE-120A, average particle size = 55 nm, manufactured by Etec Co., Ltd.). A 5% by weight aqueous solution of a nonionic surfactant (Neugen XL-40, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to 1 part by weight of a 5% by weight aqueous solution (c) Tenor NF-08, except that the Dai-ichi Kogyo Seiyaku Co., Ltd.) in the same manner as in Example 1, a water-dispersible hydrophobic resin containing low refractive index layer coating solution 11 was prepared.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 11 was 1.50.

<Preparation of Optical Reflective Film 12>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to the above. The water-dispersible hydrophobic resin-containing low-refractive index layer coating solution 11 prepared in step 1 was used, and the 19th layer from the substrate side was changed to a water-dispersible hydrophobic resin-containing low-refractive index layer. An optical reflection film 12 was produced in the same manner as in Example 1.

(Example 13)
<Preparation of optical reflection film 13>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to water. The dispersion liquid hydrophobic resin-containing low refractive index layer coating solution 10 was changed, and the first and 19th layers from the substrate side were changed to water-dispersible hydrophobic resin-containing low refractive index layers, An optical reflective film 13 was produced in the same manner as in Example 1.

(Example 14)
<Preparation of optical reflection film 14>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to water. The dispersion liquid is changed to the hydrophobic resin-containing low refractive index layer coating solution 11, and further, the first layer and the 19th layer from the substrate side are water-dispersible hydrophobic resin-containing low refractive index layers, An optical reflective film 14 was produced in the same manner as in Example 1.

(Example 15)
<Preparation of optical reflection film 15>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to water. The same as in Example 1 except that the dispersion liquid 11 was changed to the dispersion liquid 11 containing a low-refractive index layer, and all the low-refractive index layers were water-dispersible hydrophobic resin-containing low-refractive index layers. Thus, an optical reflection film 15 was produced.

(Comparative Example 1)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 12>
In Example 1 (Preparation of Dispersible Hydrophobic Resin-Containing Low Refractive Index Layer Coating Liquid 1), 10% by weight aqueous solution of acidic colloidal silica is 31 parts by weight, and 6% by weight aqueous solution of polyvinyl alcohol is 38 parts by weight. A water-dispersible hydrophobic resin-containing low refractive index coating solution 1 in the same manner as the water-dispersible hydrophobic resin-containing low refractive index coating solution 1 except that the water-dispersed urethane resin 6 mass% aqueous solution is 1 part by mass. 12 was prepared.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 12 was 1.50.

<Preparation of optical reflection film 16>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to water. An optical reflection film 16 was produced in the same manner as in Example 1 except that the coating liquid 12 was changed to the dispersible hydrophobic resin-containing low refractive index layer.

(Comparative Example 2)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 13>
In Example 1 (Preparation of coating liquid 1 containing a low-refractive index layer containing a dispersible hydrophobic resin), the water-soluble resin was a 6% by weight aqueous solution of polyvinyl alcohol (trade name: PVA-210, average polymerization degree: 1000, saponification degree). : 88 mol%, manufactured by Kuraray Co., Ltd.) 38 parts by weight, water except that the 10% by weight aqueous solution of acidic colloidal silica was 31 parts by weight and the water-dispersed urethane resin 6% by weight aqueous solution was 1 part by weight. A water-dispersible hydrophobic resin-containing low refractive index layer coating solution 13 was prepared in the same manner as the dispersible hydrophobic resin-containing low refractive index layer coating solution 1.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 13 was 1.50.

<Preparation of optical reflection film 17>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to water. The dispersion liquid is changed to the hydrophobic resin-containing low refractive index layer coating solution 13, and the 19th layer from the base material side is replaced with the 11th layer from the base material side. Except for this, an optical reflective film 17 was produced in the same manner as in Example 1.

(Comparative Example 3)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 14>
In Example 1 (preparation of coating liquid 1 having a low refractive index layer containing a dispersible hydrophobic resin), 10 mass% aqueous solution of acidic colloidal silica is 10 mass parts, 6 mass% aqueous solution of polyvinyl alcohol is 4 mass parts, A water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1 in the same manner as the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 1, except that the water-dispersible urethane resin 6 mass% aqueous solution was 65 parts by mass. 14 was prepared.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 14 was 1.50.

<Preparation of optical reflection film 18>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to water. An optical reflective film 18 was produced in the same manner as in Example 1 except that the coating liquid 14 was changed to the dispersible hydrophobic resin-containing low refractive index layer.

(Comparative Example 4)
<Preparation of water-dispersible hydrophobic resin-containing low refractive index layer coating solution 15>
In Example 1 (preparation of coating liquid 1 containing a low-refractive index resin-containing dispersive hydrophobic resin), 9 parts by mass of 10% by weight aqueous solution of acidic colloidal silica and 6% by weight aqueous solution of polyvinyl alcohol (product) (Name: JM-23, average polymerization degree: 2300, saponification degree: 97 mol%, manufactured by Nippon Bibi-Poval Co., Ltd.) 4 parts by mass, water dispersion urethane resin 6 mass% aqueous solution 65 mass parts water dispersion acrylic A water-dispersible hydrophobic property was obtained in the same manner as in Example 1 except that the resin was changed to a 6% by mass aqueous solution (AE-120A, average particle size = 55 nm, manufactured by Etec Co., Ltd.) and no nonionic surfactant was used. A resin-containing low refractive index layer coating solution 15 was prepared.

The refractive index of the film coated with the water-dispersible hydrophobic resin-containing low refractive index layer coating solution 15 was 1.50.

<Preparation of optical reflection film 19>
In Example 1 (production of the optical reflective film 1), the coating liquid for constituting the water-dispersible hydrophobic resin-containing low refractive index layer was changed from the water-dispersible hydrophobic resin-containing low refractive index layer coating liquid 1 to water. An optical reflecting film 19 was produced in the same manner as in Example 1 except that the coating liquid 15 was changed to the dispersible hydrophobic resin-containing low refractive index layer.

≪Evaluation≫
(Measure haze)
About the optical reflective film sample manufactured by the said Example and comparative example, haze (%) was measured using the haze meter (Nippon Denshoku Industries Co., Ltd. NDH2000 type | mold), and the average value of ten optical reflective film samples was computed. did. In addition, as a haze value of an optical reflection film, it should just be 2.5% or less, and it is preferable in it being 1.5% or less.

(Observation of coating failure)
The optical reflective film samples produced in the above examples and comparative examples were visually observed, and the total number (number / 1000 m ² ) of coating film failures (repelling and agglomerates) having a diameter of 2 mm or more was counted. The average value of the sheets was calculated and evaluated according to the following evaluation criteria.

○: 10 pieces / 1000 m ² or less,
○ △: 10 pieces / 1000 m ^{2 or} more, 100 pieces / 1000 m ² or less,
Δ: 100 pieces / 1000 m ^{2 or} more, 500 pieces / 1000 m ² or less,
X: More than 500 pieces / 1000 m ² .

In addition, ○, ○ △, and △ can be used without any practical problem.

(Weather resistance test)
The optical reflective films produced in the above Examples and Comparative Examples were each attached to blue glass having a thickness of 3 mm via an adhesive layer.

Specifically, the following adhesive layer forming coating solution was applied to a silicone release surface of Nakamoto Pax separator NS23MA with a comma coater so that the dry film thickness was 10 μm, and dried at 90 ° C. for 1 minute. Thus, an adhesive layer was formed. The film having the dielectric multilayer film formed thereon was bonded to this adhesive layer to form an adhesive layer on the dielectric multilayer film.

Preparation of Adhesive Layer Forming Coating Solution Coronyl (registered trademark) N-6941M (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), which is a pressure-sensitive adhesive, Add 3% by mass, add 5% by mass of Tinuvin 477 (BASF Japan Co., Ltd.), which is an ultraviolet absorber, and dilute with ethyl acetate as a solvent so that the solid content becomes 10% by mass. A forming coating solution was prepared.

This sample was subjected to a water jet of 18 minutes to xenon light having an intensity of 180 W / m ² using a xenon weather meter (manufactured by Suga Test Instruments Co., Ltd .; emitting light very close to sunlight) under conditions of 50 ° C. and 70% RH. Repeated 22 minutes of drying. Thereafter, whether or not film cracking occurred after exposure every 10 hours was visually confirmed and evaluated according to the following evaluation criteria.

A: No film breakage,
B: Slight film cracking has occurred,
C: A film crack that can be sufficiently visually confirmed has occurred,
D: Membrane cracks are clearly generated in the entire film.

The point at which the above evaluation was C or higher was defined as the crack occurrence time. The evaluation results are shown in Table 1 below.

From the results of Table 1 above, the water-dispersible hydrophobic resin-containing layer having a water-soluble resin and a water-dispersible hydrophobic resin is included, and water is added to the solid mass of the water-dispersible hydrophobic resin-containing layer. It can be seen that the optical reflective films of Examples 1 to 15 containing 5 to 55 mass% of the dispersible hydrophobic resin are superior in weather resistance as compared with the optical reflective films of Comparative Examples 1 to 4. It was also found that coating film failure was reduced.

Furthermore, in Examples 5 to 8 using an anionic emulsion resin as the water-dispersible hydrophobic resin and containing an anionic surfactant, the coating film failure is further improved as compared with Examples 1 to 4 and 9.

Further, in Examples 11 to 15 in which an anionic emulsion resin and a water-soluble resin having an average polymerization degree of 4000 to 6000 were used for the uppermost layer, the weather resistance was further improved and the haze was improved. In particular, Examples 13 and 14 in which the lowermost layer also includes a water-dispersible hydrophobic resin-containing layer containing an anionic emulsion resin, and all the low refractive index layers including the uppermost layer and the lowermost layer are water-dispersible containing an anionic emulsion resin. In Example 15 in which the hydrophobic resin-containing layer was used, it was found that the effect of improving the weather resistance was high.

Note that this application is based on Japanese Patent Application No. 2015-111712 filed on June 1, 2015, the disclosure of which is incorporated by reference in its entirety.

Claims

A substrate;
A dielectric multilayer film in which low-refractive index layers and high-refractive index layers are alternately stacked, disposed on one surface of the substrate;
At least one of the low refractive index layer and the high refractive index layer includes a water-soluble resin and a water-dispersible hydrophobic resin containing 5 to 55% by mass of a water-dispersible hydrophobic resin based on the total mass. An optical reflection film which is a containing layer.
The optical reflective film according to claim 1, wherein the water-dispersible hydrophobic resin-containing layer further contains an anionic surfactant, and the water-dispersible hydrophobic resin is an anionic emulsion resin.
The optical reflective film according to claim 1 or 2, wherein in the dielectric multilayer film, the uppermost layer opposite to the side in contact with the substrate is the water-dispersible hydrophobic resin-containing layer.
The optical reflective film according to any one of claims 1 to 3, wherein in the dielectric multilayer film, a lowermost layer in contact with the substrate is the water-dispersible hydrophobic resin-containing layer.
The top layer and the bottom layer of the dielectric multilayer film are low refractive index layers, and all the low refractive index layers are the water-dispersible hydrophobic resin-containing layers. Optical reflective film.
The optical reflective film according to any one of claims 1 to 5, wherein the water-soluble resin in the water-dispersible hydrophobic resin-containing layer has an average polymerization degree of 4000 to 6000.
A step of preparing a coating solution by dissolving or dispersing a water-soluble resin, an anionic surfactant, and an anionic emulsion resin in an aqueous solvent;
Forming the water-dispersible hydrophobic resin-containing layer by applying the coating liquid;
The manufacturing method of the optical reflection film of Claim 2 containing this.