JP2010083967A - Composition for transparent film formation and laminated transparent film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition which enables to form, on a surface of a transparent base having a refractive index of <1.55, a transparent film excellent in transparency, free of unevenness of interference, excellent in adhesion to the base, and having high film hardness, high abrasion resistance and a refractive index difference of ≤0.03 between it and the transparent base, and to provide a laminated transparent film in which a transparent film obtained by film formation from the composition is laminated on a surface of such a transparent base. <P>SOLUTION: The composition contains at least one of inorganic fine particle (A component) having a refractive index of 1.55 to <1.80, at least one of inorganic fine particle (B component) having a refractive index of <1.55, and a binder. The laminated transparent film is excellent in transparency and free of unevenness of interference, wherein a transparent film obtained by film formation from the composition is laminated on a surface of a transparent base having a refractive index of <1.55, and the difference between a refractive index of the transparent film obtained by film formation and that of the transparent base is ≤0.03. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a transparent film-forming composition and a laminated transparent film. More specifically, the surface of a transparent base material having a refractive index of less than 1.55 is excellent in transparency and has no interference unevenness, and has good adhesion to the base material. A composition capable of forming a transparent film having excellent and high film hardness and scratch resistance, and having a refractive index difference of 0.03 or less from the transparent substrate, and the composition on the surface of the transparent substrate A transparent film obtained by forming a film is laminated, and the difference between the refractive index of the transparent film obtained by forming the film and the refractive index of the transparent substrate is 0.03 or less, The present invention relates to a laminated transparent film that is excellent, has no interference unevenness, has excellent adhesion to a substrate, and has high film hardness and scratch resistance.

  In many cases, a transparent plastic film is attached to an optical member used for a display such as an LCD. In recent years, with the enhancement of functionality of flat panel displays such as plasma panel displays and liquid crystal displays, transparent plastic films are required to have high transparency, no interference unevenness, high film hardness and scratch resistance. Yes. However, transparent plastic films are generally soft and easily damaged. Therefore, by applying a transparent hard coat material to the film, a hard coat layer is formed on the film surface to improve the scratch resistance. In addition to high transparency, high adhesion to the substrate, high film hardness, and scratch resistance, the transparent hard coat layer is required to have no difference in refractive index from the transparent substrate in order to eliminate interference unevenness. ing.

  A hard coat material applied to a film having a refractive index of 1.55 or more, for example, PET (refractive index 1.65), PEN (refractive index 1.76), etc. is transparent using a high refractive index inorganic oxide. A composition for forming a high refractive index film or a composition for forming a transparent conductive high refractive index film is widely used (see, for example, Patent Documents 1 and 2). Such a composition for forming a transparent high refractive index film or a composition for forming a transparent conductive high refractive index film can form a film having a refractive index equivalent to that of a substrate having a refractive index exceeding 1.55. A film having a refractive index equivalent to that of a substrate having a refractive index of less than 1.55 cannot be formed.

  On the other hand, for a film having a refractive index of less than 1.55, for example, TAC (refractive index 1.49), as a method of forming a hard coat layer, (meth) acryloyl polyfunctional resin, having a specific functional group ( A hard coat material using a (meth) acryloyl resin, a urethane acrylate resin, an isocyanurate, or the like has been reported (see, for example, Patent Documents 3 to 5). However, with these methods, it is difficult to form a film that satisfies both sufficient scratch resistance and high adhesion to the substrate.

A method of using a composition for forming a transparent film in which inorganic fine particles are dispersed in a binder has also been reported (see, for example, Patent Documents 6 and 7). By using inorganic fine particles, the adhesion to the substrate can be improved. The inorganic fine particles added in the inventions described in Patent Documents 6 and 7 are colloidal silica (refractive index 1.46) and zinc antimonate (refractive index 1.7 to 1.9), respectively, and have different refractive indexes. Two or more kinds of inorganic materials are not contained. In these cases, it is difficult to form a film having no interference unevenness and no difference in refractive index from the base material on a transparent base material having a refractive index of less than 1.55.
JP 2002-167576 A JP 2008-138084 A JP 2001-113648 A JP 2003-306619 A JP 2007-237483 A JP 2000-007944 A JP 2001-123036 A

  The present invention has been made in view of the above-mentioned problems. (1) The surface of a transparent substrate having a refractive index of less than 1.55 is excellent in transparency and has no interference unevenness, and has good adhesion to the substrate. An excellent composition having high film hardness and scratch resistance, and capable of forming a transparent film having a refractive index difference of 0.03 or less from the transparent substrate; (2) A transparent film obtained by depositing the composition is laminated, and the difference between the refractive index of the transparent film obtained by depositing the film and the refractive index of the transparent substrate is 0.03 or less. An object of the present invention is to provide a laminated transparent film having excellent film hardness and scratch resistance, excellent in adhesion with a substrate, excellent in adhesion unevenness.

  As a result of intensive studies to achieve the above-mentioned various objects, the present inventors have found that at least one kind of inorganic fine particles (component A) having a refractive index of 1.55 or more and less than 1.80, a refractive index of 1.55. The present invention was completed by finding that the intended effect can be obtained by using a composition containing at least one kind of inorganic fine particles (component B) and a binder that are less than the above.

  That is, the composition for forming a transparent film of the present invention includes at least one kind of inorganic fine particles (component A) having a refractive index of 1.55 or more and less than 1.80, and at least one kind of refractive index of less than 1.55. It contains inorganic fine particles (component B) and a binder.

  The transparent film-forming composition of the present invention comprises at least one kind of inorganic fine particles (component A) having a refractive index of 1.55 or more and less than 1.80, and at least one kind of refractive index of less than 1.55. It contains inorganic fine particles (component B), at least one kind of inorganic fine particles (component C) having a refractive index of 1.80 or more and 2.20 or less, and a binder.

  Further, in the laminated transparent film of the present invention, a transparent film obtained by forming the transparent film forming composition on the surface of the transparent substrate is laminated, and the refractive index of the transparent film obtained by forming the film is formed. And the refractive index of the transparent substrate is 0.03 or less.

  By forming a film using the composition for forming a transparent film of the present invention, a laminated transparent film having high transparency and no interference unevenness can be formed in a single layer formation, and the coating process is compared with the conventional method. Since there are few, it can manufacture at low cost.

Embodiments of the present invention will be specifically described below.
The composition for forming a transparent film of the present invention comprises at least one inorganic fine particle (component A) having a refractive index of 1.55 or more and less than 1.80, and at least one inorganic fine particle having a refractive index of less than 1.55. (Component B) and a binder, preferably containing at least one kind of inorganic fine particles (component C) having a refractive index of 1.80 to 2.20, preferably further a dispersion stabilizer. Contains a dispersion medium.

  The shape of the inorganic fine particles that are the A component, B component, and C component used in the present invention is not particularly limited, but is preferably spherical. Moreover, about the magnitude | size of A component, B component, and C component, a primary particle diameter can respectively use 1-100 nm normally, Preferably 5-40 nm can be used. It is preferable that the particle diameters of the A component, B component, and C component are the same. The primary particle size can be calculated from the BET method.

  Component A is added to adjust the refractive index of the transparent film to be formed and further relieve the internal stress of the film. As component A, inorganic fine particles having a refractive index of 1.55 or more and less than 1.80 are added. Use. In addition, the refractive index of each material is a value intrinsic | native to a material, and is described in various literature. About the kind of A component, if the objective can be achieved, it will not specifically limit, Well-known things, such as a commercial item, can be used. For example, aluminum oxide (refractive index 1.76), magnesium oxide (refractive index 1.64 to 1.74), aluminum hydroxide (refractive index 1.58), calcium carbonate (refractive index 1.57 to 1.60). Barium sulfate (refractive index 1.65), antimony pentoxide (refractive index 1.65), and the like are used. As the component A, only one type may be used, or two or more types may be used in combination, and conductive fine particles may be used for the purpose of imparting antistatic properties.

  The B component is added to adjust the refractive index of the transparent film to be formed and further relieve the internal stress of the film, and inorganic fine particles having a refractive index of less than 1.55 are used as the B component. About the kind of B component, if the objective can be achieved, it will not specifically limit, Well-known things, such as a commercial item, can be used. For example, silica (refractive index 1.46), silica particles containing air (hollow silica etc.) (refractive index 1.30 to 1.45), magnesium fluoride (refractive index 1.38 to 1.40) ), Calcium fluoride (refractive index of 1.43 to 1.45) and the like are used. B component may use only 1 type, or may use 2 or more types together.

  The component C can be supplementarily added to adjust the refractive index of the transparent film to be formed and further relieve the internal stress of the film. As the C component, inorganic fine particles having a refractive index of 1.80 or more and 2.20 or less are used. Use of inorganic fine particles having a refractive index exceeding 2.20 is not preferable because the refractive index of the film tends to be too high. About the kind of C component, if the objective can be achieved, it will not specifically limit, Well-known things, such as a commercial item, can be used. For example, strontium oxide (refractive index 1.87), zirconium oxide (refractive index 2.2), or the like can be used. As C component, only 1 type may be used or 2 or more types may be used together. In addition, conductive fine particles can be used for the purpose of imparting antistatic properties. For example, antimony-doped tin oxide (ATO) (refractive index 2.0), tin-doped indium oxide (ITO) (refractive index 2.0), aluminum-doped zinc oxide (AZO) (refractive index 2.0), tin oxide ( Refractive index 2.0), zinc oxide (refractive index 2.0), or the like can be used. In addition, about the tin oxide, what doped elements, such as phosphorus, can also be used. As for zinc oxide, one doped with gallium or aluminum can also be used.

  The type of the binder is not particularly limited as long as the object can be achieved, and a known product such as a commercial product can be used. Any binder that is generally used in paints can be used without particular limitation as long as it can be dissolved in the dispersion medium used, can disperse the inorganic fine particles, and can form a film. Although the refractive index of a binder will not be specifically limited if the objective can be achieved, Preferably, it is 1.47 or more and less than 1.55.

  In the present invention, the difference in refractive index between the A component and the B component is preferably 0.05 or more, more preferably 0.15 or more. When the C component is added, the difference in refractive index between the A component and the C component is preferably 0.05 or more, more preferably 0.15 or more. Moreover, it is preferable that the refractive index of a binder is lower than A component.

  In the present invention, as the binder, for example, alkyd resin, polyester resin, unsaturated polyester resin, polyurethane resin, acrylic resin, epoxy resin, phenol resin, vinyl resin, silicone resin, fluorine resin, phthalic acid resin, amino resin, polyamide A resin, a polyacryl silicone resin, a melamine resin, a urea resin, or a binder resin obtained by modifying these can be used alone or in combination of two or more.

  Further, the binder may contain a crosslinking agent as necessary, for example, a basic functional group such as an amino group, a neutral functional group such as an OH group, an acidic functional group such as a carboxyl group, an isocyanate group. Any cross-linking agent having two or more reactive functional groups in one molecule can be used.

  The binder may be an active energy ray curable compound, and examples thereof include a radical polymerizable monomer and a radical polymerizable oligomer. Specific examples of the radical polymerizable monomer include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, and tetrahydrofurfuryl. (Meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, methoxypolyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, polyethylene glycol Polypropylene glycol mono (meth) acrylate, polyethylene glycol polytetramethylene glycol mono (meth) acrylate, group Monofunctional (meth) acrylates such as sidyl (meth) acrylate; ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (Meth) acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, allyl di (meth) acrylate, bisphenol A di (meth) acrylate, ethylene oxide modified bisphenol A di (meth) acrylate, polyethylene oxide modified Bisphenol A di (meth) acrylate, ethylene oxide modified bisphenol S di (meth) acrylate, bisphenol S di (meth) Bifunctional (meth) acrylates such as acrylate, 1,4-butanediol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate; trimethylolpropane tri (meth) acrylate, glycerol tri (meth) acrylate, Trifunctional or higher functional groups such as pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, ethylene-modified trimethylolpropane tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, etc. (Meth) acrylate; radically polymerizable monomers such as styrene, vinyltoluene, vinyl acetate, N-vinylpyrrolidone, acrylonitrile, allyl alcohol and the like.

  Specific examples of radically polymerizable oligomers include polyester (meth) acrylate, polyurethane (meth) acrylate, epoxy (meth) acrylate, polyether (meth) acrylate, oligo (meth) acrylate, alkyd (meth) acrylate, and polyol (meth). Examples thereof include prepolymers having at least one (meth) acryloyl group such as acrylate and silicone (meth) acrylate. Particularly preferred radical polymerizable oligomers are (meth) acrylates of polyester, epoxy, and polyurethane. In this invention, an active energy ray hardening compound can be used individually by 1 type, or 2 or more types can be used together.

  When an active energy ray-curable compound is used as the binder, the composition for forming a transparent film can be cured by irradiation with a small amount of active energy rays by adding a photopolymerization initiator (photosensitizer). it can.

  As a photopolymerization initiator (photosensitizer), for example, 1-hydroxycyclohexyl phenyl ketone, benzophenone, benzyl dimethyl ketone, benzoin methyl ether, benzoin ethyl ether, p-chlorobenzophenone, 4-benzoyl-4-methyldiphenyl sulfide, Examples include 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone-1. A photoinitiator can be used individually by 1 type, or can also use 2 or more types together.

  In the composition for forming a transparent film of the present invention, it is preferable to add a dispersion stabilizer for the purpose of further improving the dispersion stability and storage stability of the inorganic fine particles in the composition for forming a transparent film. Examples of the dispersion stabilizer that can be used in the present invention include chelating agents and metal complexes. By adding a chelating agent or a metal complex, the dispersion stability of the inorganic fine particles can be improved without lowering the hardness and scratch resistance of the formed film.

  The chelating agent that can be used in the present invention is preferably soluble in a dispersion medium, and as such a chelating agent, polyamines such as ethylenediamine, diethylenetriamine, and triethylenetetramine, pivaloyltrifluoroacetone, acetylacetone, Examples include β-diketones such as trifluoroacetylacetone and hexafluoroacetylacetone, polyaminocarboxylic acids such as ethylenediaminetetraacetic acid, oxycarboxylic acids such as citric acid, oximes such as dimethylglyoxime, oxine, and oxalic acid. A chelating agent can be used individually by 1 type, or can use 2 or more types together.

  The metal complex that can be used in the present invention is preferably soluble in a dispersion medium. As such a metal complex, a metal selected from the group consisting of zirconium, titanium, aluminum, zinc, indium, and tin, Polyamines such as ethylenediamine, diethylenetriamine and triethylenetetramine, β-diketones such as pivaloyltrifluoroacetone, acetylacetone, trifluoroacetylacetone and hexafluoroacetylacetone, polyaminocarboxylic acids such as ethylenediaminetetraacetic acid, and oxy such as citric acid Mention may be made of metal complexes comprising carboxylic acids, oximes such as dimethylglyoxime, ligands selected from the group consisting of oxine and oxalic acid. These metal complexes can be used alone or in combination of two or more. Furthermore, one or more chelating agents and one or more metal complexes can be mixed and used.

  In addition, you may add another dispersing agent in order to improve the storage stability of the composition for transparent film formation of this invention more. Although such a dispersing agent is not specifically limited, As the illustration, Preferably, the phosphate ester type dispersing agent which has a polyoxyethylene alkyl structure can be mentioned.

  In the composition for forming a transparent film of the present invention, a dispersion medium can be added at an arbitrary ratio. As a dispersion medium, alcohols such as water, methanol, ethanol, isopropanol, normal butanol, 2-butanol and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and 4-hydroxy-4-methyl-2-pentanone Esters such as ethyl acetate, butyl acetate, ethyl lactate, γ-butyrolactone, propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate; ethers such as ethylene glycol monomethyl ether and diethylene glycol monobutyl ether; benzene, toluene, xylene, Aromatic hydrocarbons such as ethylbenzene; dimethylformamide, N, N-dimethylacetoacetamide, N-methylpyrrolidone and the like Mention may be made of the earth and the like. Among these dispersion media, it is more preferable to use a dispersion medium that has particularly good dispersibility of the inorganic fine particles and good film forming properties during coating. Examples of such a dispersion medium include ethanol, isopropanol, normal butanol, 2-butanol, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, ethyl acetate, butyl acetate, toluene, xylene, Mention may be made of ethylbenzene. In the present invention, the dispersion medium may be used alone or in combination of two or more.

  In the composition for forming a transparent film of the present invention, the blending ratio of the component A and the component B must be appropriately set according to the refractive index of the transparent substrate on which the composition for forming a transparent film is applied. The mass ratio of the A component and the B component (A component / B component) is preferably 15/85 to 95/5, more preferably 20/80 to 90/10. When the mass ratio of the B component is lower than 5% based on the total mass of the A component and the B component, the interference unevenness of the formed film tends to be noticeable. Conversely, when the mass ratio of the B component is higher than 85%, the refractive index of the film cannot be increased to a desired level.

  In the composition for forming a transparent film of the present invention, when the C component is added, the blending ratio of the total of the A component and the B component and the C component is that of the transparent substrate on which the transparent film forming composition is applied. Although it is necessary to set appropriately according to the refractive index, the mass ratio of the sum of the A component and the B component and the C component ((A component + B component) / C component) is preferably 30/70 to 100 / 0, more preferably 50/50 to 100/0. When the mass ratio of the C component is higher than 70% based on the total mass of the inorganic fine particles, the refractive index of the formed film becomes too high.

  In the composition for forming a transparent film of the present invention, the blending ratio of each component needs to be appropriately set according to the refractive index of the transparent substrate on which the composition for forming a transparent film is applied. The total mass ratio of the component, the B component and the C component) and the solid content of the binder is preferably 20/80 to 90/10, more preferably 30/70 to 75/25. When the mass ratio of the binder solid content is lower than 10% based on the total mass of the A component, the B component, the C component, and the solid content of the binder, the film hardness and transparency tend to decrease, from 80% If it is high, the internal stress becomes high and the adhesion is lowered.

  In the composition for forming a transparent film of the present invention, the mass ratio of the inorganic fine particles (the total of component A and component B) to the dispersion stabilizer is preferably 99.8 / 0.2 to 66.7 / 33.3. More preferably, it is 99.0 / 1.0-76.9 / 23.1. When the mass ratio of the dispersion stabilizer is lower than 0.2% based on the total mass of the inorganic fine particles and the dispersion stabilizer, the improvement of the storage stability of the composition is insufficient, and it is higher than 33.3%. In some cases, the dispersion stabilizer tends to settle without dissolving.

  The composition for forming a transparent film of the present invention can be produced by adding component A, component B, component C (only when added supplementarily) and a binder in any order or simultaneously, and mixing them well. . A dispersion medium can be added as needed. Moreover, after manufacturing separately the composition (A component containing composition) which consists of A component and a binder, and the composition (B component containing composition) which consists of B component and a binder, A component containing composition and B component It can also be produced by mixing the containing composition. When the C component is supplementarily added, a composition composed of the C component and the binder (C component-containing composition) is produced, and the A component-containing composition, the B component-containing composition, and the C component-containing composition are mixed. Can also be manufactured. Also in this case, the dispersion medium can be appropriately added as necessary. Generally, the A component, the B component, and the C component (only when supplementally added) are dispersed in a dispersion medium to produce a dispersion, and then a binder is added to obtain a transparent film forming composition. It is even better to perform a pre-dispersion operation before performing the dispersion operation. In the pre-dispersion operation, the components A, B and C (only when supplemented) are gradually added to the dispersion medium while stirring with a disperser, etc., and the components A, B and C (auxiliary) are added. (Only when it is added automatically) can be carried out by stirring well until no lump is visually confirmed. Moreover, when adding a dispersion stabilizer, it is preferable to add A component, B component, C component, and a binder in arbitrary order or simultaneously in the dispersion medium which melt | dissolved the dispersion stabilizer.

  The dispersion operation of the A component, the B component, and the C component (only when supplementarily added) can be performed using a paint shaker, a ball mill, a sand mill, a sentry mill, or the like. It is preferable to use dispersed beads such as glass beads and zirconia beads during the dispersion operation. The bead diameter is not particularly limited, but is usually about 0.05 to 1 mm, preferably about 0.08 to 0.65 mm.

  In the composition for forming a transparent film of the present invention, the average particle size of the inorganic fine particles which are the A component, the B component and the C component is preferably 120 nm or less, and more preferably 80 nm or less. When the average particle diameter exceeds 120 nm, the haze (JIS K 7105) of the formed film tends to increase.

  The composition for forming a transparent film of the present invention can be used by being included in a composition for forming a protective film, a composition for forming an antireflection film, an adhesive, a sealing material, a binder material, etc., and particularly forming an antireflection film. It can use suitably for the composition to do.

  Furthermore, the composition for forming a transparent film of the present invention may contain various conventional additives other than those described above as long as the purpose is not impaired. Examples of such additives include a polymerization inhibitor, a curing catalyst, an antioxidant, a leveling agent, and a coupling agent.

  The composition for forming a transparent film of the present invention is a transparent substrate having a refractive index of less than 1.55, such as polymethyl methacrylate, polyester, polyolefin, epoxy resin, melamine resin, triacetyl cellulose resin, ABS resin, norbornene resin, It can be applied or printed on various transparent substrates made of glass or the like and cured to form a film.

  The laminated transparent film of the present invention is obtained by laminating the transparent film obtained by depositing the transparent film-forming composition on the surface of the transparent substrate. The transparent substrate and the transparent film forming composition are selected so that the difference between the refractive index of the film and the refractive index of the transparent substrate is preferably 0.03 or less, more preferably 0.02 or less. When the difference between the refractive index of the transparent film obtained by the film formation and the refractive index of the transparent base material is larger than 0.03, interference unevenness tends to occur remarkably.

  Application or printing of the composition for forming a transparent film on the transparent substrate is in accordance with a conventional method, for example, bar coating, gravure coating, roll coating, spin coating, screen printing, ink jet method, air spray, airless spray, electrostatic coating, etc. It can be performed according to the method.

  When a thermosetting resin is contained as a binder, the film can be formed by a method such as baking. The temperature during baking is preferably lower than the glass transition temperature of the transparent substrate.

When an active energy ray-curable compound is contained as a binder, the dispersion medium is evaporated by heating as necessary, the coating film is dried, and then active energy rays (ultraviolet rays or electron beams) are irradiated. As the active energy ray source, an ultraviolet ray source such as a low pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, a xenon lamp, an excimer laser, or a dye laser, and an electron beam accelerator can be used. The irradiation amount of the active energy ray is suitably within the range of 50 to 3000 mJ / cm ² in the case of ultraviolet rays and 0.2 to 1000 μC / cm ² in the case of electron beams. By irradiation with this active energy ray, the active energy ray-curable compound is polymerized to form a film in which the A component and the B component are bonded with a binder.

  The film thickness of the transparent film obtained by curing the composition for forming a transparent film of the present invention is preferably in the range of 0.1 to 10.0 μm, more preferably in the range of 0.3 to 5.0 μm. is there. In the transparent film obtained by curing the composition for forming a transparent film of the present invention, the A component, the B component, the C component (only when supplemented only) and the binder are uniformly dispersed in the film, and interference occurs. There is no unevenness, transparency is high, haze is low, and the difference between the refractive index of the transparent film and the refractive index of the transparent substrate is preferably 0.03 or less, more preferably 0.02 or less. Furthermore, the light transmittance is preferably 80% or more, more preferably 85% or more, and the haze is preferably 1.5% or less, more preferably 1.0% or less.

The present invention will be specifically described below with reference to examples and comparative examples. In Examples and Comparative Examples, “parts” are all “parts by mass”.
Various components used in Examples and Comparative Examples are as follows.

<A component>
Aluminum oxide (Al ₂ O ₃ ) (refractive index 1.76, primary particle diameter 20 nm)
Magnesium oxide (MgO) (refractive index 1.72, primary particle diameter 30 nm)
Antimony pentoxide (Sb ₂ O ₅ ) (refractive index 1.65, primary particle diameter 30 nm)

<B component>
Silica (SiO ₂ ) (refractive index 1.46, primary particle diameter 30 nm)
Hollow silica (refractive index 1.40, primary particle diameter 30nm)

<C component>
ATO (refractive index 2.0, primary particle diameter 30 nm)
Zinc oxide (ZnO) (refractive index 2.03, primary particle diameter 30 nm)
Tin oxide (SnO ₂ )

<Dispersion stabilizer>
Acetylacetone (C ₅ H ₇ O ₂ )
Ethylenediamine (C ₂ H ₈ N ₂ )
Triethylenetetramine (C ₆ H ₁₈ N ₄ )
Pivaloyl trifluoroacetone Aluminum acetylacetonate ([Al (C ₅ H ₇ O ₂ ) ₃ ])
Zinc acetylacetonate ([Zn (C ₅ H ₇ O ₂ ) ₂ ])
Dibutyl-tin bisacetylacetonate ([(C ₄ H ₉ ) ₂ Sn (C ₅ H ₇ O ₂ ) ₂ ])

<Binder>
DPHA (refractive index: 1.49) manufactured by Nippon Kayaku Co., Ltd.
Fluoropolymer (refractive index 1.40)

<Photopolymerization initiator>
IRGACURE 184, manufactured by Ciba Specialty Chemicals Co., Ltd.
<Dispersion medium>
BYK-142 (NV. 60% or more) manufactured by Big Chemie Japan Co., Ltd.

Example 1
All ingredients were placed in a container in an amount of 60 parts antimony pentoxide, 40 parts silica, 10 parts BYK-142, 200 parts 2-butanol and 800 parts glass beads and kneaded for 7 hours in a paint shaker. . After kneading, the glass beads were removed to obtain a dispersion. 122 parts of DPHA, 12.2 parts of IRGACURE 184 and 320 parts of 2-butanol were added to this dispersion to obtain a photocurable composition. After applying this photocurable composition on a TAC film (light transmittance 93%, haze 0.5%, refractive index 1.49) using a roll coater and evaporating the organic dispersion medium Then, 300 mJ / cm ² of light was irradiated using a high pressure mercury lamp in an air atmosphere to produce a laminated transparent film having a film thickness of 3 μm.

Example 2
Put all ingredients in a container in an amount of 15 parts aluminum oxide, 35 parts silica, 50 parts ATO, 10 parts BYK-142, 200 parts 2-butanol and 800 parts glass beads, and 7 in a paint shaker I kneaded time. After kneading, the glass beads were removed to obtain a dispersion. 43 parts of DPHA, 4.3 parts of IRGACURE 184 and 130 parts of 2-butanol were added to this dispersion to obtain a photocurable composition. Using a roll coater, this photocurable composition is applied onto a 75 μm-thick cyclic olefin film X (light transmittance 91%, haze 0.5%, refractive index 1.53) to evaporate the organic dispersion medium. After that, 300 mJ / cm ² of light was irradiated using a high-pressure mercury lamp in an air atmosphere to produce a laminated transparent film having a film thickness of 3 μm.

Example 3
70 parts of magnesium oxide, 30 parts of hollow silica, 10 parts of BYK-142, 200 parts of 2-butanol and 800 parts of glass beads were added to all the components in a container and kneaded with a paint shaker for 7 hours. . After kneading, the glass beads were removed to obtain a dispersion. 43 parts of DPHA, 4.3 parts of IRGACURE 184 and 130 parts of 2-butanol were added to this dispersion to obtain a photocurable composition. Thereafter, a laminated transparent film having a film having a thickness of 3 μm was produced in the same manner as in Example 1.

Example 4
Put all ingredients in a container in an amount of 30 parts magnesium oxide, 30 parts hollow silica, 40 parts zinc oxide, 10.0 parts BYK-142, 200 parts 2-butanol and 800 parts glass beads, Kneaded for 7 hours with a paint shaker. After kneading, the glass beads were removed to obtain a dispersion. 122 parts of DPHA, 12.2 parts of IRGACURE 184 and 320 parts of 2-butanol were added to this dispersion to obtain a photocurable composition. Using a roll coater, this photocurable composition is applied onto a 75 μm-thick cyclic olefin film Y (light transmittance 91%, haze 0.6%, refractive index 1.51) to evaporate the organic dispersion medium. Thereafter, a 300 mJ / cm ² light was irradiated using a high-pressure mercury lamp in an air atmosphere to produce a laminated transparent film having a film thickness of 3 μm.

Example 5
Put all the ingredients in a container in the amount of 30 parts magnesium oxide, 30 parts hollow silica, 40 parts tin oxide, 10 parts BYK-142, 200 parts 2-butanol and 800 parts glass beads, paint shaker And kneaded for 7 hours. After kneading, the glass beads were removed to obtain a dispersion. 27 parts of a fluoropolymer, 40 parts of DPHA, 6.7 parts of IRGACURE 184 and 190 parts of 2-butanol were added to this dispersion to obtain a photocurable composition. Thereafter, a laminated transparent film having a film having a thickness of 3 μm was produced in the same manner as in Example 1.

Example 6
Put all ingredients in a container in an amount that will result in 15 parts aluminum oxide, 35 parts silica, 50 parts ATO, 11 parts acetylacetone, 10 parts BYK-142, 200 parts 2-butanol and 800 parts glass beads. Kneaded for 7 hours with a paint shaker. After kneading, the glass beads were removed to obtain a dispersion. 43 parts of DPHA, 4.3 parts of IRGACURE 184 and 130 parts of 2-butanol were added to this dispersion to obtain a photocurable composition. Using a roll coater, this photocurable composition is applied onto a 75 μm-thick cyclic olefin film X (light transmittance 91%, haze 0.5%, refractive index 1.53) to evaporate the organic dispersion medium. Thereafter, 300 mJ / cm ² of light was irradiated using a high-pressure mercury lamp in an air atmosphere to produce a laminated transparent film having a film thickness of 3 μm.

Example 7
A photocurable composition was obtained in the same manner as in Example 6 except that 43 parts of aluminum acetylacetonate was added instead of 11 parts of acetylacetone. Thereafter, a laminated transparent film having a film having a thickness of 3 μm was produced by the same method as in Example 6.

Example 8
60 parts antimony pentoxide, 40 parts silica, 10 parts BYK-142, 5.5 parts ethylenediamine, 5.5 parts dibutyl-tin bisacetylacetonate, 200 parts 2-butanol and 800 parts glass All components were put in a container in an amount to become beads and kneaded for 7 hours with a paint shaker. After kneading, the glass beads were removed to obtain a dispersion. 122 parts of DPHA, 12.2 parts of IRGACURE 184 and 320 parts of 2-butanol were added to this dispersion to obtain a photocurable composition. After applying this photocurable composition on a TAC film having a film thickness of 75 μm (light transmittance 93%, haze 0.5%, refractive index 1.49) using a roll coater and evaporating the organic dispersion medium. Then, 300 mJ / cm ² of light was irradiated using a high-pressure mercury lamp in an air atmosphere to produce a laminated transparent film having a film thickness of 3 μm.

Example 9
A photocurable composition was obtained in the same manner as in Example 8 except that 11 parts of triethylenetetramine was added instead of 5.5 parts of ethylenediamine and 5.5 parts of dibutyl-tin bisacetylacetonate. Thereafter, a laminated transparent film having a film thickness of 3 μm was produced by the same method as in Example 8.

Example 10
30 parts magnesium oxide, 30 parts hollow silica, 40 parts zinc oxide, 11 parts zinc acetylacetonate, 10.0 parts BYK-142, 200 parts 2-butanol and 800 parts glass beads All ingredients were placed in a container and kneaded for 7 hours with a paint shaker. After kneading, the glass beads were removed to obtain a dispersion. 122 parts of DPHA, 12.2 parts of IRGACURE 184 and 320 parts of 2-butanol were added to this dispersion to obtain a photocurable composition. Using a roll coater, this photocurable composition is applied onto a 75 μm-thick cyclic olefin film Y (light transmittance 91%, haze 0.6%, refractive index 1.51) to evaporate the organic dispersion medium. Then, a 300 mJ / cm ² light was irradiated using a high-pressure mercury lamp in an air atmosphere to produce a laminated transparent film having a film thickness of 3 μm.

Example 11
A photocurable composition was obtained in the same manner as in Example 10 except that 5.5 parts of pivaloyltrifluoroacetone and 5.5 parts of zinc acetylacetonate were added instead of 11 parts of zinc acetylacetonate. . Thereafter, a laminated transparent film having a film thickness of 3 μm was produced by the same method as in Example 10.

Comparative Example 1
All components were placed in a container in amounts of 100 parts aluminum oxide, 10 parts BYK-142, 200 parts 2-butanol and 800 parts glass beads and kneaded for 7 hours in a paint shaker. After kneading, the glass beads were removed to obtain a dispersion. To this dispersion, 567 parts DPHA, 5.7 parts IRGACURE 184 and 1360 parts 2-butanol were added to obtain a photocurable composition. Thereafter, a laminated transparent film having a film having a thickness of 3 μm was produced in the same manner as in Example 1.

Comparative Example 2
A photocurable composition was obtained in the same manner as in Comparative Example 1 except that 567 parts of DPHA, 1360 parts of 2-butanol were replaced by 82 parts of DPHA and 220 parts of 2-butanol. Thereafter, a laminated transparent film having a film having a thickness of 3 μm was produced in the same manner as in Example 1.

Comparative Example 3
All components were placed in a container in amounts of 100 parts silica, 10 parts BYK-142, 200 parts 2-butanol and 800 parts glass beads and kneaded for 7 hours in a paint shaker. After kneading, the glass beads were removed to obtain a dispersion. 100 parts DPHA, 10 parts IRGACURE 184 and 270 parts 2-butanol were added to this dispersion to obtain a photocurable composition. Thereafter, a laminated transparent film having a film having a thickness of 3 μm was produced in the same manner as in Example 2.

Comparative Example 4
All components were placed in a container in an amount of 90 parts antimony pentoxide, 10 parts silica, 10 parts BYK-142, 200 parts 2-butanol and 800 parts glass beads and kneaded for 7 hours in a paint shaker. . After kneading, the glass beads were removed to obtain a dispersion. 43 parts of DPHA, 4.3 parts of IRGACURE 184 and 134 parts of 2-butanol were added to this dispersion to obtain a photocurable composition. Thereafter, a laminated transparent film having a film having a thickness of 3 μm was produced in the same manner as in Example 1.

<Evaluation method>
(1) Average particle diameter (median diameter) of the film-forming composition
Measuring instrument: Microtrac particle size distribution meter manufactured by Nikkiso Co., Ltd. Measuring condition: Temperature 20 ° C
Sample: NV. Measurement after dilution to 5% Data analysis conditions: Particle diameter standard Volume standard Dispersion medium: 2-butanol Refractive index: 1.40

(2) Refractive Index of Transparent Film Regarding the transparent films (not including the transparent base material) formed in Examples 1 to 11 and Comparative Examples 1 to 4, Atago Co., Ltd. Abbe refractometer DR-M4 (20 ° C).

(3) Transmittance and Haze of Laminated Transparent Film The transmittance and haze of the laminated transparent films obtained in Examples 1 to 11 and Comparative Examples 1 to 4 were measured with TC-HIII DPK manufactured by Tokyo Denshoku Technical Center. The measured value is a measured value of the laminated transparent film including the transparent substrate.

(4) Film hardness of the laminated transparent film (pencil scratch hardness)
The laminated transparent film transparent cured coating surfaces obtained in Examples 1 to 11 and Comparative Examples 1 to 4 were evaluated under a load of 500 g in accordance with JIS K 5600-5-4.

(5) Scratch resistance of laminated transparent film Surface after 10 reciprocal abrasions of steel film (# 0000) and 500 g load on the laminated transparent film transparent cured coating surface obtained in Examples 1 to 11 and Comparative Examples 1 to 4 The state was visually evaluated according to the following criteria.
○: No scratch △: Some scratches ×: Scratches

(6) Adhesiveness of laminated transparent film The laminated transparent film transparent cured coating surfaces obtained in Examples 1 to 11 and Comparative Examples 1 to 4 were subjected to a peel test using a cellophane adhesive tape and visually evaluated according to the following criteria. .
○: No peeling △: Partial peeling ×: Full peeling

(7) Interference unevenness of laminated transparent film The laminated transparent films obtained in Examples 1 to 11 and Comparative Examples 1 to 4 were visually observed under a three-wavelength fluorescent lamp and evaluated according to the following criteria.
○: No interference unevenness △: Interference unevenness is very small, but practical use ×: Interference unevenness occurs remarkably −: Since haze is high, evaluation is not possible

  The results of the above measurements and the results of evaluation are shown in Tables 1 and 2 together with the composition of each composition.

  As is apparent from the data shown in Tables 1 and 2, the refractive index and transparent substrate of the laminated transparent film containing A component and B component, or A component and B component and C component, When the difference from the refractive index is 0.02 or less (Examples 1, 2, 4 to 11), there is no interference unevenness, the film hardness and scratch resistance are high, the transmittance is 85% or more, and haze 1 A film of less than 0.0% was obtained. In the case where the difference between the refractive index of the laminated transparent film formed and the refractive index of the transparent substrate was 0.03 (Example 3), a slight amount of interference unevenness was generated. There wasn't. Moreover, when the dispersion stabilizer was used (Examples 6 to 11), the particle diameter of the film-forming composition showed a stable value for one year, and the storage stability was improved as compared with the case where it was not added. Further, when the B component was not added (Comparative Examples 1 and 2), there was no interference unevenness and a laminated transparent film having high adhesion could not be obtained. In the case where the component A was not contained (Comparative Example 3), it was not possible to obtain a laminated transparent film in which the difference between the refractive index of the formed laminated transparent film and the refractive index of the transparent substrate could be 0.03 or less. . Further, when the difference between the refractive index of the formed transparent film and the refractive index of the transparent substrate exceeds 0.03 (Comparative Example 4), interference unevenness is caused even if the A component and the B component are contained. Remarkably occurred.

Claims (12)

  Containing at least one inorganic fine particle (component A) having a refractive index of 1.55 or more and less than 1.80, at least one inorganic fine particle (component B) having a refractive index of less than 1.55, and a binder. A composition for forming a transparent film.   At least one kind of inorganic fine particles (A component) having a refractive index of 1.55 or more and less than 1.80, at least one kind of inorganic fine particles (B component) having a refractive index of less than 1.55, and a refractive index of 1.80. A composition for forming a transparent film, comprising at least one kind of inorganic fine particles (component C) of 2.20 or less and a binder.   The C component is composed of at least one selected from zirconium oxide, antimony-doped tin oxide (ATO), tin-doped indium oxide (ITO), aluminum-doped zinc oxide (AZO), tin oxide, and zinc oxide. 2. The composition for forming a transparent film according to 2.   A composition for forming a transparent film according to claim 1, 2 or 3, further comprising a dispersion stabilizer.   The composition for forming a transparent film according to claim 4, wherein the dispersion stabilizer is at least one selected from the group consisting of a chelating agent and a metal complex.   6. The transparent film forming material according to claim 5, wherein the chelating agent comprises at least one selected from the group consisting of polyamines, β-diketones, polyaminocarboxylic acids, oxycarboxylic acids, oximes, oxines and oxalic acid. Composition.   The metal complex is selected from the group consisting of zirconium, titanium, aluminum, zinc, indium and tin, and the group consisting of polyamines, β-diketones, polyaminocarboxylic acids, oxycarboxylic acids, oximes, oxine and oxalic acid. The composition for forming a transparent film according to claim 5, which comprises a ligand to be formed.   The component A comprises at least one selected from aluminum oxide, magnesium oxide, aluminum hydroxide, calcium carbonate, barium sulfate, and antimony pentoxide, for forming a transparent film according to any one of claims 1 to 7. Composition.   The composition for forming a transparent film according to claim 1, wherein the component B comprises silica.   The refractive index of a binder is 1.47 or more and less than 1.55, The composition for transparent film formation in any one of Claims 1-9 characterized by the above-mentioned.   A transparent film obtained by forming the transparent film forming composition according to any one of claims 1 to 10 on the surface of a transparent substrate having a refractive index of less than 1.55 is laminated, and the film formation A laminated transparent film, wherein the difference between the refractive index of the transparent film obtained by the process and the refractive index of the transparent substrate is 0.03 or less.   12. The laminated transparent film according to claim 11, wherein the light transmittance is 80% or more and the haze is 1.5% or less.