JPH10100310A - Heat-ray shading film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent film high in visible light transmissivity and markedly excellent in heat ray shading capacity. SOLUTION: A heat ray shading film is provided by coating a metallized film with a resin compsn. based on fine metal particles with a primary particle size of 0.5μm or less having infrared absorbing capacity and active energy beam polymerizable (meth)acrylate. This film is excellent in scratch resistance and shows high visible light transmissivity and markedly excellent heat ray shading capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat ray-shielding film, and in particular, is characterized in that a film having excellent weather resistance and transparency and excellent heat ray absorbing ability can be obtained.

[0002]

2. Description of the Related Art Heat ray blocking films have been actively researched and developed in recent years, and can be used as information recording materials, infrared cut filters or heat ray blocking films in building windows, vehicle windows, and the like. .

[0003] In recent years, attention has been paid to the effect of reducing the cooling load in buildings and vehicles. In order to block solar energy flowing through windows, there is a limit only to reflection in the visible region, and reflection and absorption in the visible region. In addition to the near-infrared-
It is necessary to increase the absorption capacity. Heat ray shielding materials are materials that have been actively researched and developed in recent years.In particular, interest in metal thin films having high reflection characteristics in the visible-infrared region has been increasing. Techniques for coating and adding functions such as selective permeability have been actively studied in various fields, and have been commercialized and put into practical use as so-called heat ray shielding glasses. On the other hand, a method of attaching an infrared shielding film, in which a heat ray reflective material is coated on a film, to a window glass or a car glass has been widely used because it is inexpensive and simpler. In order to obtain a high reflectance, a material having a high refractive index is desirable for the film,
_{i0 2, Fe 2 0 3,} CoO, Cr 2 0 3 vacuum deposition Au, Cr, a metal thin film of Al or the like is an oxide, and as the metal film in particular has a near infrared high reflectance, such as ,
Alternatively, a coating method using a thin film processing method such as a sputter method has been performed. Generally, a film on which aluminum is deposited at a low cost is generally commercialized. On the other hand, a method of coating or kneading an infrared-absorbing light-transmitting material that absorbs heat rays and has a heat ray blocking performance, for example, chromium, cobalt complex salt thiol nickel complex, anthraquinone derivative, phthalocyanine derivative, amino compound, etc. Processed into film. Although these processed films transmit visible light, they absorb near-infrared-infrared heat rays, so when applied to openings such as glass windows, they absorb the heat rays of solar rays or radiant heat to adjust sunlight and heat insulation. Has an effect. The heat ray shielding film having the effect of blocking the heat rays in the sunlight by reflecting or absorbing near infrared rays-infrared rays in this way,
It is used for building windows, freezer / refrigerated showcases, heat-insulating surfaces, vehicle windows, etc., and is useful for improving the living environment and saving energy.

[0004]

However, a conventional heat-reflective film on which a metal is vapor-deposited reflects not only heat rays but also visible rays with a metal vapor-deposited layer if heat ray-shielding performance is emphasized. There was a fatal defect that lighting was impaired and the room became dark. Among these metals, aluminum is widely used for buildings and car windows because of its low cost. Aluminum vapor deposition products are generally used as vapor deposition products having a visible light transmittance of 50% to 20%. This aluminum vapor-deposited product needs to have low visible light transmittance in order to obtain a sufficient heat ray blocking property, and becomes dark. Also, if the transmittance is low, the reflection of visible light will be strong, so it will have a mirror-like appearance,
There is also a disadvantage that glare due to reflected light is inevitable.

[0005] In addition, conventional films processed using a light-transmitting material having an infrared-absorbing property are poor in durability when organic films are used, and the initial heat ray blocking effect is deteriorated with changes in environmental conditions and with the passage of time. There was a drawback to go. On the other hand, the complex type has durability, but has a large absorption not only in the near-infrared region but also in the visible region, and has a drawback that its use is limited because it is strongly colored.

Further, in order to form a film of the heat ray absorbent, it is necessary to uniformly disperse the heat ray absorbent in the resin. As the resin binder, thermoplastic resins such as acrylic resins, polyester resins, alkyd resins, polyurethane resins, epoxy resins, amino resins, and vinyl resins are generally used. However, these resins used as binders have low film hardness and are easily scratched, and have poor scratch resistance. When a heat ray-shielding film is produced using these resins, it is desired to further hard coat the outer surface to improve practical scratch resistance. However, hard coating again after coating the heat ray shielding material has a disadvantage that the cost is high and the versatility is poor.

[0007] A film having a function of having high visible light transmittance, excellent weather resistance and extremely high heat ray blocking performance has not yet been found. Undesirable phenomena have occurred such that when trying to increase the visible light transmittance, the heat ray blocking performance decreases, and conversely, when trying to increase the heat ray blocking performance, the visible light transmittance decreases and the weather resistance decreases. Here, it has been desired to develop a durable heat ray-shielding film that has solved these drawbacks and has a high visible light transmittance while having a high heat ray-blocking performance.

[0008]

Means for Solving the Problems The present inventor has conducted intensive studies on a heat ray shielding material which exhibits a large absorption over a wide range of the infrared region, has a high visible light transmittance and is excellent in durability. A film coated with a heat ray-shielding coating made by dispersing metal fine particles having a primary particle diameter of 0.5 μm or less, preferably 0.1 μm or less in a UV-curable resin binder on a film on which is deposited. The inventors have found that the obtained film achieves the above object, and have completed the present invention.

According to the present invention, by combining a vapor-deposited metal having a heat ray reflecting ability and a heat ray shielding performance by metal fine particles having a heat ray absorbing ability, a high heat ray shielding property which is unprecedented while having a high visible light transmittance. In addition to being able to have an effect, it is extremely durable because it uses all inorganic heat ray absorbents, and it has an ultraviolet curing type with a (meth) acryloyl group as a resin to fix these heat ray absorbents. By using a resin, a film excellent in scratch resistance and durability can be efficiently formed. In addition, as described above, the deposited metal generally has an excellent heat ray reflection effect, but has a large effect of lowering the visible light transmittance, whereas the heat ray blocking coating used in combination with the present invention has an extremely excellent visible light transmittance. In addition, there is an effect that the decrease in the visible light transmittance is greatly alleviated as compared with the method using only the evaporated metal. In addition, the heat ray-shielding paint containing the metal fine particles used in the present invention has a large effect of absorbing heat rays, but has a small performance of reflecting visible light, and therefore has less mirror reflection and lower visibility than when only a vapor-deposited metal is used. There is an effect of improving.

The metallized film used in the present invention has a visible light transmittance of 20% or more and 90% or less, preferably 40% or less.
More than 80% is desirable in view of the balance between the heat ray blocking performance and the visible light transmittance. The base material of the film is polyester, polyethylene, polypropylene polystyrene, polycarbonate, polyvinyl chloride, poly (meth)
Acrylic, polyamide, or polyurethane is used as a base material, and polyester is particularly suitable in terms of processability and strength. These film bases preferably have high transparency, but a colored transparent film base may be used as desired. Examples of the metal used for the metal-deposited film include aluminum, copper, gold, and chromium. However, the metal is not limited to this as long as it has a function of blocking heat rays. The metal-deposited film can be produced by a known method, for example, a vacuum deposition method or a sputtering method. It is also possible to coat a further resin layer to protect the metal deposited on the film.

The metal having a heat ray absorbing ability contained in the heat ray blocking paint used in the present invention includes titanium oxide, zinc oxide, indium oxide, tin oxide, antimony oxide, zinc sulfide, glass ceramics, and the like. Tin oxide, A
Metal oxides such as TO (antimony-doped tin oxide), ITO (indium-doped tin oxide), gels of anhydrous zinc antimonate, antimony pentoxide, and vanadium oxide have excellent heat ray absorbing ability and are suitable. In order to form such a metal as a transparent metal-containing film having no absorption in the visible light region and having a primary particle diameter of 0.5 μm or less, preferably 0.1 μm or less, it is necessary to use ultrafine powder. . The fine particles must be kept stable without agglomeration in the binder resin. The content of the inorganic metal fine particles with respect to the solid content in the heat ray-shielding paint used in the present invention can be arbitrarily selected according to the required heat ray-shielding ability, but is preferably 20% by weight to 70% by weight. It is suitable. ATO is disclosed in, for example, JP-A-58-117228, JP-A-6-262717, and JP-A-2-105.
875, etc., and ITO can be produced, for example, by the method described in JP-A-63-11519. A method for producing anhydrous zinc antimonate is disclosed in Japanese Patent Laid-Open No. 6-21974.
Antimony pentoxide can be obtained by a method described in Japanese Patent Publication No. 3-17234 or Japanese Patent Publication No. 7-29773. Vanadium pentoxide can be produced by beneficiation of natural ores or by heating ammonium metavanadate.

The UV-curable resin used in the present invention can be arbitrarily selected from UV-curable (meth) acrylates having one or more (meth) acryloyl groups in the molecule, and may be used alone or as a mixture. be able to. Specific examples of this (meth) acrylate include 2-
Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, isobutyl (meth)
Acrylate, t-butyl (meth) acrylate, 2-
Ethylhexyl (meth) acrylate, stearyl acrylate, 2-ethylhexyl carbitol acrylate, ω-carboxypolycaprolactone monoacrylate, acryloyloxyethyl acid, acrylic acid dimer, lauryl (meth) acrylate, 2-methoxyethyl acrylate, butoxyethyl acrylate, ethoxy Ethoxyethyl acrylate, methoxytriethylene glycol acrylate, methoxypolyethylene glycol acrylate, stearyl (meth) acrylate,
Cyclohexyl (meth) acrylate, tetosehydrofurfuryl (meth) acrylate, N-vinyl-2-pyrrolidone, isobonyl (meth) acrylate, dicyclopentenyl acrylate, benzyl acrylate, phenylglycidyl ether epoxy acrylate, phenoxyethyl (meth) acrylate, Phenoxy (poly) ethylene glycol acrylate, nonylphenol ethoxylated acrylate, acryloyloxyethyl phthalic acid, tribromophenyl acrylate, tribromophenol ethoxylated (meth) acrylate, methyl methacrylate, tribromophenyl methacrylate, methacryloyloxyethyl acid, methacryloyloxyethyl Maleic acid, methacryloyloxyethyl hexahydrophthalic acid, methacrylic acid Loyloxyethyl phthalic acid, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, β-carboxyethyl acrylate, N-methylolacrylamide, N-methoxymethylacrylamide, N-ethoxymethylacrylamide, Nn- Butoxymethylacrylamide, t-butylacrylamide sulfonic acid, vinyl stearylate, N-methylacrylamide,
N-dimethylacrylamide, N-dimethylaminoethyl (meth) acrylate, N-dimethylaminopropylacrylamide, acryloylmorpholine, glycidyl methacrylate, n-butyl methacrylate, ethyl methacrylate, allyl methacrylate, cetyl methacrylate, pentadecyl methacrylate , Methoxypolyethylene glycol (meth) acrylate, diethylaminoethyl (meth) acrylate, methacryloyloxyethyl succinic acid, hexanediol diacrylate,
Neopentyl glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, hydroxypivalate neopentyl, pentaerythritol diacrylate monostearate,
Glycol diacrylate, 2-hydroxyethyl methacryloyl phosphate, bisphenol A ethylene glycol adduct acrylate, bisphenol F ethylene glycol adduct acrylate, tricyclodecane methanol diacrylate, trishydroxyethyl isocyanurate diacrylate, 2-hydroxy-1
Acryloxy-3-methacryloxypropane, trimethylolpropane triacrylate, trimethylolpropane ethylene glycol adduct triacrylate, trimethylolpropane propylene glycol adduct triacrylate, pentaerythritol triacrylate,
Trisacryloyloxyethyl phosphate, trishydroxyethyl isocyanurate triacrylate, modified ε-caprolactone triacrylate, trimethylolpropaneethoxy triacrylate, glycerin propylene glycol adduct triacrylate, pentaerythritol tetraacrylate, pentaerythritol ethylene glycol adduct tetraacrylate ,
Examples include, but are not limited to, ditrimethylolpropane tetraacrylate, dipentaerythritol hexa (penta) acrylate, dipentaerythritol monohydroxypentaacrylate, urethane acrylate, epoxide acrylate, polyester acrylate, and unsaturated polyester. . These can be used singly or arbitrarily as a mixture. Preferably, the polyfunctional (meth) acrylate monomer or oligomer containing two or more (meth) acryloyl groups in the molecule has a hard film after polymerization, and has an excellent resistance. The abrasion is good and suitable. The ratio of these UV-curable (meth) acrylates to the resin component in the coating material is preferably from 10% by weight to 98% by weight, more preferably from 30% by weight to 80% by weight.

In addition to the UV-curable resin having a (meth) acryloyl group as a binder component, acrylic resin is also used for the purpose of improving the adhesion to a film or the compatibility between inorganic metal fine particles and the UV-curable resin. Polymers such as resin, polyester resin and butyral resin can be added. For example, as a polyester resin, Byron (a polyester resin manufactured by Toyobo Co., Ltd.) can be used, and as a butyral resin, an Selec manufactured by Sekisui Chemical can be mentioned. In particular, polymers having hydroxyl groups, such as polyester resin and polybutyral resin, have good dispersibility of metal oxides, and at the same time, have the function of improving ink adhesion and reducing film shrinkage. It is suitable. The ratio of the polymer to the resin component in the heat ray-shielding coating material is preferably 2% by weight or more and 50% by weight or less, more preferably 20% by weight or less. If the content of this polymer is too large, the abrasion resistance of the coating film obtained is reduced, and it is not particularly suitable for the method of using the coating film surface outside.

[0014] In order to disperse the ultrafine particles of the inorganic metal in the ultraviolet curable resin, a surfactant may be further added as required. As the dispersant, various surfactants are used, for example, anionic surfactants such as sulfate esters, carboxylic acids, and polycarboxylic acids, cationic surfactants such as quaternary salts of higher aliphatic amines, and higher fatty acids. Nonionic surfactants such as polyethylene glycol esters, amphoteric surfactants, silicone surfactants,
There are a fluorosurfactant, a polymer activator having an amide ester bond and the like. The amount of the dispersant added is preferably from 0.1% by weight to 10% by weight based on the total weight of the inorganic metal fine particles.

In curing the paint used in the present invention, a photopolymerization initiator is used, and the photopolymerization initiator is dissolved in a resin binder in advance. The photopolymerization initiator is not particularly limited and various known ones can be used. The amount of the photopolymerization initiator is 0.1 to 15% by weight, preferably 0.5 to 12% by weight based on the resin component. If the amount is too small, the curability deteriorates, which is not preferable. If the amount is too large, the strength of the cured film decreases. Specific examples of the photopolymerization initiator include Irgacure-184 and Irgacure-651.
(Manufactured by Ciba Geigy), Darocure-1173 (manufactured by Merck), benzophenone, methyl O-benzoylbenzoate, p-dimethylbenzoate, thioxanthone,
Examples thereof include alkylthioxanthone and amines.

Further, various slip agents can be added for the purpose of improving the slip property of the surface of the coating film.
Further, an antifoaming agent can be added for the purpose of controlling foam generated when the composition is applied. Further various organic solvents as required, for example, toluene, xylene, ethyl acetate,
Aromatic or aliphatic organic solvents such as alcohols can be added.

BEST MODE FOR CARRYING OUT THE INVENTION

The film of the present invention has a primary particle size of 0.5 having an infrared absorbing ability on a transparent film on which metal is deposited.
It can be obtained by coating a heat ray-shielding paint composed of fine particles of an inorganic metal having a diameter of not more than μm and an ultraviolet-curable (meth) acrylate having a (meth) acryloyl group.
The coating surface of the heat-shielding paint may be on the opposite surface where the metal is deposited or on the upper layer where the metal is deposited. Conversely, it is also possible to apply the heat ray-shielding paint used in the present invention on a transparent film and deposit a metal on the upper surface or the opposite surface. In any case, it is desirable that the actual surface to be used be the hard coat layer, and therefore it is desirable to design the surface to be coated with the heat ray-shielding paint used in the present invention to be the surface to be used. When the metal deposition surface is designed to be the use surface, it is necessary to further provide a hard coat resin layer in order to protect the metal deposition. Examples of the method for producing the ultraviolet-curable heat ray-shielding paint and the method for coating the film with the film in the present invention include the following methods. Preferably, a small amount of a dispersant and a polymer resin are added to a metal dispersion finely dispersed to 0.5 μm or less in an organic solvent in advance to stabilize the dispersion of the fine particles. Thereafter, an uncured (meth) acrylate monomer or oligomer which can be polymerized by irradiation with an active energy ray is added alone or in combination of two or more, and the polymerization initiator is further dissolved to obtain a desired heat ray-shielding paint. At this time, an appropriate amount of a solvent or various additives can be added as needed. The method of mixing these components is not limited to this order, and is not particularly limited as long as the method is to stabilize the metal fine particles. As a method of coating the heat ray shielding paint on the metal vapor deposited film, for example, dipping method, gravure coating method, offset coating method, roll coating method, bar coating method, performed by a conventional method such as spraying method, after coating with hot air The heat ray blocking composition coated on the film surface is instantaneously polymerized and cured by evaporating the solvent and subsequently irradiating ultraviolet rays. The thickness of the dried coating film to be coated is 1 to 10 μm, preferably 2 to 5 μm from the viewpoint of curling prevention. The heat ray-shielding film thus obtained can be further pasted and attached as necessary.

[0018]

EXAMPLES Next, the heat ray-shielding film according to the present invention will be described in detail with reference to examples.

Example 1 A container equipped with a stirrer was charged with 50 parts of a toluene solution containing 50% of ATO finely dispersed to a particle size of 0.1 μm or less.
5 (polycarboxylic acid-based dispersant manufactured by Kyoeisha Yushi Co., Ltd.)
% Of a toluene solution containing 5% by weight. Subsequently, while further stirring, 7 parts of the polyester resin Byron 24SS was added little by little and dissolved. Subsequently, 12.5 parts of toluene and 22.5 parts of an ultraviolet-curable monomer, dipentaerythritol hexaacrylate, are added and dissolved, and 2 parts of a photopolymerization initiator, Irgacure 184, are further dissolved to dissolve the ultraviolet-curable heat-ray shielding property. Paint was obtained. Using a wire bar, the above-mentioned heat-ray-blocking paint was applied with a solid bar at a solid content of 6.7 g / m on the opposite surface of a vapor-deposited film having a visible light transmittance of 56% in which aluminum was deposited on a transparent polyester film having a thickness of 50 μm. m2. 80 solvent
After drying with hot air at a temperature of 80 ° C., a high-thickness mercury lamp of 80 W was irradiated at a conveyor speed of 20 m / min to polymerize and cure the coating film to obtain a desired heat ray-shielding coating film.

[0019]

Example 2 A heat ray-shielding coating was obtained in the same manner as in Example 1 except that the same amount of gel of anhydrous zinc antimonate was used instead of ATO. Visible light transmittance 56 obtained by depositing aluminum on a transparent polyester film having a thickness of 25 μm.
% Of the vapor-deposited film was coated with the above-mentioned heat ray-shielding paint using a wire bar so that the applied amount of the solid content was 6.7 g / m2. After the solvent was dried with hot air at 80 ° C, an 80W high-pressure mercury lamp was conveyed at a conveyor speed of 20 ° C.
Irradiation was performed at a speed of m / min to polymerize and cure the coating film to obtain a desired heat ray-shielding coating film.

[0020]

COMPARATIVE EXAMPLE 1 The heat-ray-shielding paint obtained in Example 1 was coated on a transparent polyester film having a thickness of 50 μm on which aluminum had not been vapor-deposited by using a wire bar with a solid content of 6.7 g / m 2. It was coated to become. 8 solvent
After drying with hot air at 0 ° C., a high-pressure mercury lamp of 80 W was irradiated at a conveyor speed of 20 m / min to polymerize and cure the coating film to obtain a heat ray-shielding coating film.

For reference, the vapor deposited film itself used in Example 1 and a commercially available black colored film for vehicle use were subjected to the test. Table 1 shows the properties of the obtained film.

[0022]

[Table 1] Visible light transmittance was measured according to JIS A 5759. The solar absorptivity was measured according to JIS R 3106. (The larger the numerical value of the solar absorptivity, the more excellent the heat ray shielding performance.) The scratch resistance was measured with steel wool No. 0000, 200 g load and 20 reciprocations. ：: not damaged at all ×: damaged

[0023]

The heat ray-shielding film obtained by the present invention has excellent scratch resistance, high transparency in the visible light region, is transparent, and exhibits remarkably excellent heat ray-shielding performance. Further, the heat ray-shielding paint used in the present invention easily forms a hard film by irradiating ultraviolet rays, so that it has excellent workability and is most suitable for application to buildings, vehicle windows, optical equipment, and the like.

Claims (4)

[Claims] 1. A heat-shielding device comprising, as a component, fine particles of an inorganic metal having a primary particle diameter of 0.5 μm or less having a heat-ray absorbing ability and a binder curable by ultraviolet rays as an adhesive on a film on which a metal is deposited. A heat-shielding film coated with a conductive paint. 2. The inorganic fine particles are at least one metal selected from the group consisting of tin oxide, ATO (antimony-doped tin oxide), ITO (indium-doped tin oxide), gel of anhydrous zinc antimonate, antimony pentoxide, and vanadium oxide. The film of claim 1 which is an oxide. 3. The heat ray-shielding film according to claim 1, wherein a UV-curable resin having a (meth) acryloyl group is used as a binder. 4. A coating material comprising a binder containing at least one thermoplastic polymer selected from an acrylic resin, a polyester resin, and a butyral resin in addition to an ultraviolet curable resin as a binder component. Heat ray blocking film.