JP2003183586A - Transparent hard coat layer and material, and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hard coat layer that is suitable for an anti-reflection film and has high hardness and high transparency, to provide a hard coat mate rial and a display device having the hard coat layer on coated with the hard coat material. <P>SOLUTION: The hard coat layer 1 comprising a transparent resin film 2 which contains fine particles 3 having a core-shell structure is laminated on a transparent substrate 4 to provide the hard coat layer and material. Anti- reflection films 7a and 7b, an antifouling layer 8 is further laminated on the hard coat layer 1 to thereby form a good anti-reflection film 9. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises, for example, a film-shaped, sheet-shaped, or plate-shaped transparent material that is disposed on the front surface of a display device and is useful for preventing light reflection, contamination, charging, and the like. The present invention relates to a hard coat layer and a hard coat material suitable for, and a display device in which these are arranged.

[0002]

2. Description of the Related Art It has been done in various fields for a long time to protect a surface of a product by coating and to adjust gloss, but in recent years, ionizing radiation curable resin compositions such as acrylates have been developed. It is often practiced to apply a particularly hard coating film, commonly known as a hard coat, on furniture, kitchen equipment,
It is applied to electrical appliances, office equipment, optical equipment, and other items that are often encountered around us. In addition, since the materials such as acrylates that make up the hard coat are highly reactive, various substances can be added to a part of the structure, or they can be physically confined in the crosslinked structure of the coating film to add high hardness. Therefore, it is possible to maintain various functions for a long period of time.

Among various fields, display devices are used in various audiovisual devices, computer terminals, and various portable terminal devices. The number of popularized display devices is very large. Among them, liquid crystal display devices consume less power. It is especially frequently used because it has few. Display devices such as liquid crystal display devices require a high degree of durability because the environment in which they are used and the manner in which they are used are highly demanding, and especially the display surface is scratched, contaminated, or charged. Not to do anything
A protective material having various functions is often arranged on the front surface.

By the way, when applying a hard coat to these display devices, it is necessary to ensure transparency in view of the function of the display device, but conventionally, in other fields, the purpose is to improve the hardness of the coating film. As described above, when a high hardness and relatively large particle size such as silica or alumina is compounded in the coating film, the decrease in transparency due to an increase in the compounding amount cannot be avoided. It was

Further, in order to impart antireflection property to a display device, it is necessary to laminate a thin film of metal oxide or the like as an antireflection film on a transparent hard coat. The surface of the hard coat, which is the base, is required to be smooth. However, if silica or alumina with a small particle size is used to smooth the surface,
The effect of filling was poor and only a coating film with insufficient hardness was obtained.

[0006]

Therefore, in the present invention, it is possible to provide irregularities, but basically, the surface is smooth, the hardness is high, the transparency is high, and various substances can be added as necessary. With a part of the structure or physically confined in the crosslinked structure of the coating film, etc., a hard coat that can have various functions, and a hard coat with a hard coat on the substrate An object of the present invention is to provide a material and a display device in which such a hard coat or a hard coat material is arranged.

[0007]

As a result of studies by the inventors, it was found that a hard coat having high hardness and high transparency can be obtained by using synthetic resin fine particles having a core-shell structure. The hard coat could have various substances as part of its structure or could be physically trapped in the crosslinked structure of the coating.

The first invention comprises a dispersion film in which fine particles of synthetic resin having a core-shell structure in which the glass transition temperature of the core portion is higher than the glass transition temperature of the shell portion are dispersed in a binder made of a crosslinked synthetic resin. The present invention relates to a transparent hard coat layer characterized by the above. In a second aspect based on the first aspect, the average particle size X of the synthetic resin fine particles and the mass-based content Y (%) of the synthetic resin fine particles in the dispersion film are represented by the following formulas. The present invention relates to a transparent hard coat layer having a relationship. −8.3286Ln (X) + 58.68 ≦ Y ≦ −16.
934Ln (X) +118.68 3rd invention is the said 1st or 2nd invention WHEREIN: The said core part of the said synthetic resin fine particle has bridge | crosslinked, and the said shell part has not bridge | crosslinked, or the said core. The part relates to a transparent hard coat layer having a higher crosslink density than the shell part. The fourth invention is
In any one of the first to third inventions, the present invention relates to a transparent hard coat layer having fine irregularities on the surface. A fifth invention relates to the transparent hard coat layer according to any one of the first to fourth inventions, characterized in that an antireflection film is laminated on the surface. A sixth invention relates to the transparent hard coat layer according to any one of the first to fifth inventions, wherein an antifouling layer is laminated on the outermost surface. A seventh invention relates to a transparent hard coat material, characterized in that the hard coat layer according to any one of the first to sixth inventions is laminated on a transparent substrate. An eighth invention relates to a display device characterized in that the transparent hard coat layer of any one of the first to sixth inventions or the transparent hard coat material of the seventh invention is arranged on the viewing side of the display device. It is a thing.

[0009]

The figures all show the hard coat layer, the hard coat material, or the display device of the present invention. First, the outline of the present invention will be described with reference to the drawings.

The hard coat layer 1 of the present invention is shown in FIG.
As shown in FIG. 1, it is composed of a transparent dispersion film in which transparent synthetic resin fine particles 3 are dispersed in a transparent synthetic resin 2. Further, the hard coat material 1 ′ of the present invention is shown in FIG. 1 (b). Thus, the transparent dispersion film in which the transparent synthetic resin fine particles 3 are dispersed in the transparent synthetic resin 2, that is, the hard coat layer 1 in FIG. 1A is laminated on the transparent substrate 4. .

As shown in FIG. 2, in the hard coat layer 1 or the hard coat material 1'of the present invention, the upper surface of the dispersion film in which the synthetic resin fine particles 3 are dispersed in the synthetic resin 2 has the unevenness 5. By doing so, when the display device is viewed through the hard coat layer 1 or the hard coat material 1 ′, the so-called “glitter” in which the image light looks high in brightness at a specific position is mitigated. You can

As shown in FIG. 3, the hard coat layer 1 or the hard coat material 1 ′ of the present invention has an antireflection film (FIG. 3) on the upper surface of a dispersion film in which synthetic resin fine particles 3 are dispersed in a synthetic resin 2. In this example, the antireflection films 7a and 7b) may be laminated. Further, the hard coat layer 1 or the hard coat material 1 ′ of the present invention may have an antifouling layer 8 laminated on the uppermost surface as shown in FIG. Instead of being laminated only on the film, it may be directly laminated on the dispersion film in which the synthetic resin fine particles 3 are dispersed in the synthetic resin 2, that is, on the upper surface of the hard coat layer without the antireflection film.

The hard coat layer 1 of the present invention as described above,
Alternatively, as shown in FIG. 4, it is preferable that the hard coat material 1 ′ is arranged on the observation side (upper side in FIG. 4) of the liquid crystal panel and used. Of course, as the hard coat layer or the hard coat, those described with reference to FIG. 2 or 3 may be used. In this example,
The liquid crystal panel 11 has a light guide plate 12 arranged on the back surface thereof,
The liquid crystal panel is illuminated by the light source 13 and the reflection plate 14 (referred to as "backlight method"), and the liquid crystal panel has a liquid crystal layer sandwiched between front and rear glass plates with transparent electrodes on the inner surface of the transparent glass plate. The image displayed according to the signal is visually recognized through a polarizing plate, a color filter, etc., but the influence of external light at the time of observation is hard coat layer 1 or hard coat material 1 ′. By arranging, you try to avoid. There is also a front light method for lighting the liquid crystal panel, so in that case,
A hard coat layer may be laminated on the observation side of the light guide plate, or a hard coat material may be arranged in front of the light guide plate.

The hard coat layer 1 can be used by directly laminating it on the front surface of a display device, but generally, the hard coat layer 1 is used by laminating it on a transparent substrate 4. Is normal. The transparent base material 4 is preferably one that has transparency and smoothness and is free from foreign matter, and that has mechanical strength for processing and use. Further, when heat of the display is transmitted to the hard coat layer 1 or the hard coat material 1 ', it is preferable to use a material having heat resistance.

The transparent substrate 4 is a generally transparent thermoplastic resin film, and preferred examples thereof include cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, polyester, polyamide, polyimide, polyether sulfone, Polysulfone, polypropylene, polymethylpentene, polyvinyl chloride, polyvinyl acetal, polyether ketone,
Examples thereof include thermoplastic resin films such as polymethylmethacrylate, polycarbonate, or polyurethane.

In the case of a photographic film coated with a photographic emulsion, polyester which is often used and cellulose triacetate which is also often used in a photographic film because of its high transparency and no optical anisotropy are usually used. preferable.

Although these thermoplastic resin films are flexible and easy to use, there is no need to bend them even during handling, and when a hard material is desired, a plate-like plate such as the above-mentioned resin plate or glass plate is required. Things can also be used. The thickness is preferably about 8 to 1000 μm, but in the case of a plate-shaped material, this range may be exceeded.

The transparent base material 4 described above is subjected to various treatments that can be usually carried out, that is, physical treatments such as corona discharge treatment and oxidation treatment, in order to improve the adhesiveness with the layer formed thereon. In addition to the treatment, a coating called an anchor agent or a primer may be applied in advance to form the primer layer.

The hard coat layer 1 may be composed of a thermoplastic resin or a thermosetting resin such as polyurethane resin as a synthetic resin component depending on the use. If further effect is desired, ionizing radiation curable resin,
Alternatively, it is more preferable that the ionizing radiation-curable composition containing the ionizing radiation-curable compound is crosslinked and cured by irradiation with ionizing radiation.

The ionizing radiation-curable composition is a mixture of a prepolymer, an oligomer and / or a monomer having a polymerizable unsaturated bond or an epoxy group in the molecule. Ionizing radiation refers to electromagnetic waves or charged particle beams having an energy quantum capable of polymerizing or cross-linking molecules, and usually uses ultraviolet rays or electron beams.

Examples of prepolymers and oligomers in the ionizing radiation-curable composition are unsaturated polyesters such as condensation products of unsaturated dicarboxylic acids and polyhydric alcohols, polyester methacrylates, polyether methacrylates, polyol methacrylates, melamine methacrylates. Methacrylates such as polyester acrylate,
Examples thereof include acrylates such as epoxy acrylate, urethane acrylate, polyether acrylate, polyol acrylate, and melamine acrylate, and cationic polymerization type epoxy compounds.

Examples of the monomer in the ionizing radiation curable composition include styrene, styrene-based monomers such as α-methylstyrene, methyl acrylate, 2-ethylhexyl acrylate, methoxyethyl acrylate, butoxyethyl acrylate, Acrylic esters such as butyl acrylate, methoxybutyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, methoxyethyl methacrylate, ethoxymethyl methacrylate, phenyl methacrylate, lauryl methacrylate, etc. Methacrylic acid esters, 2- (N, N-diethylamino) ethyl acrylate, 2- (N, N-dimethylamino) ethyl acrylate, 2- (N, N-dibenzylamino) methyl acrylate, Acrylic acid-2- (N, N Unsaturated substituted amino alcohol esters such as diethylamino) propyl, unsaturated carboxylic acid amides such as acrylamide and methacrylamide, ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diester Compounds such as acrylate and triethylene glycol diacrylate, polyfunctional compounds such as dipropylene glycol diacrylate, ethylene glycol diacrylate, propylene glycol dimethacrylate, and diethylene glycol dimethacrylate, and / or two or more thiol groups in the molecule. Having a polythiol compound, such as trimethylolpropane trithioglycolate, trimethylolpropane trithiopropylate, pentaeryth Litol tetrathioglycolate and the like can be mentioned.

Usually, as the monomer in the ionizing radiation-curable composition, one of the above compounds is used or a mixture of two or more thereof is used, if necessary. 5% by weight or more of the prepolymer or oligomer, the monomer and / or
Alternatively, the polythiol compound content is preferably 95% by weight or less.

When flexibility is required when the ionizing radiation-curable composition is applied and cured, the amount of the monomer may be reduced or an acrylate monomer having 1 or 2 functional groups may be used. When abrasion resistance, heat resistance, and solvent resistance when an ionizing radiation-curable composition is applied and cured are required, an acrylate monomer having three or more functional groups is used, and ionizing radiation curing is performed. It is possible to design the sexual composition. Here, assuming that the functional group is 1,
2-hydroxy acrylate, 2-hexyl acrylate, phenoxyethyl acrylate are mentioned. Examples of those having 2 functional groups include ethylene glycol diacrylate and 1,6-hexanediol diacrylate. Examples of functional groups having 3 or more groups include trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and dipentaerythritol hexaacrylate.

To adjust physical properties such as flexibility and surface hardness when the ionizing radiation-curable composition is applied and cured, a resin which is not cured by irradiation with ionizing radiation is added to the ionizing radiation-curable composition. You can also The following are specific examples of the resin. It is a thermoplastic resin such as polyurethane resin, cellulose resin, polyvinyl butyral resin, polyester resin, acrylic resin, polyvinyl chloride resin, or polyvinyl acetate. Above all, the addition of polyurethane resin, cellulose resin, polyvinyl butyral resin and the like is preferable from the viewpoint of improving flexibility.

When the ionizing radiation curable composition is cured by irradiation with ultraviolet rays, a photopolymerization initiator or a photopolymerization accelerator is added. As the photopolymerization initiator, in the case of a resin system having a radically polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether and the like are used alone or in combination. In the case of a resin system having a cationically polymerizable functional group, an aromatic diazonium salt, an aromatic sulfonium salt, an aromatic iodonium salt, a metacelone compound, a benzoin sulfonic acid ester or the like is used alone or as a mixture as a photopolymerization initiator. . The addition amount of the photopolymerization initiator is 0.1 to 10 parts by weight with respect to 100 parts by weight of the ionizing radiation-curable composition.

The following organic reactive silicon compounds may be used in combination with the ionizing radiation curable composition.

One of the organosilicon compounds has the general formula R _m Si
(OR ') _n , where R and R'have 1 carbon
Each of the subscript m of R and the subscript n of R ′ represents an alkyl group of 10 to 10 and is an integer satisfying the relation of m + n = 4.

Specifically, tetramethoxysilane, tetraethoxysilane, tetra-iso-propoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxysilane. , Tetrapentaethoxysilane, tetrapenta-iso-propoxysilane, tetrapenta-n-propoxysilane, tetrapenta-n-
Butoxysilane, tetrapenta-sec-butoxysilane, tetrapenta-tert-butoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, dimethyldimethoxysilane,
Dimethyldiethoxysilane, dimethylethoxysilane,
Dimethylmethoxysilane, dimethylpropoxysilane,
Examples thereof include dimethylbutoxysilane, methyldimethoxysilane, methyldiethoxysilane and hexyltrimethoxysilane.

The organosilicon compound 2 which can be used in combination with the ionizing radiation-curable composition is a silane coupling agent.

Specifically, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, β-
(3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ
-Methacryloxypropyl methoxysilane, N-β-
(N-Vinylbenzylaminoethyl) -γ-aminopropylmethoxysilane hydrochloride, γ-glycidoxypropyltrimethoxysilane, aminosilane, methylmethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ- Examples thereof include chloropropyltrimethoxysilane, hexamethyldisilazane, vinyltris (β-methoxyethoxy) silane, octadecyldimethyl [3- (trimethoxysilyl) propyl] ammonium chloride, methyltrichlorosilane and dimethyldichlorosilane.

Three of the organosilicon compounds that can be used in combination with the ionizing radiation-curable composition are ionizing radiation-curable silicon compounds. Specific examples thereof include a plurality of functional groups that react and crosslink upon irradiation with ionizing radiation, for example, an organosilicon compound having a molecular weight of 5,000 or less and having a polymerizable double bond group, and more specifically, one end thereof. Vinyl functional polysilane,
Examples thereof include vinyl functional polysilane at both ends, vinyl functional polysiloxane at both ends, vinyl functional polysiloxane at both ends, vinyl functional polysilane obtained by reacting these compounds, vinyl functional polysiloxane, and the like.

More specifically, the following compounds are used.

[0034]

[Chemical 1]

Other organic silicon compounds that can be used in combination with the ionizing radiation-curable composition include (meth) acryl groups such as 3- (meth) acryloxypropyltrimethoxysilane and 3- (meth) acryloxypropylmethyldimethoxysilane. Roxysilane compounds and the like can be mentioned.

In the present invention, the synthetic resin fine particles 3 dispersed in the hard coat layer have a core-shell structure having a double structure of a core portion (core portion) and a shell portion (outer shell portion). , The diameter of the synthetic resin fine particles 3 is 10n
It is preferably from m to 700 nm. If the diameter of the synthetic resin fine particles 3 is less than 10 nm, the effect of improving the hardness of the hard coat layer is poor even if compounded, and
This is because if it exceeds 700 nm, the transparency of the hard coat layer is lowered by blending.

The synthetic resin constituting the core portion and the shell portion of the synthetic resin fine particles 3 is basically not limited, but the hard coat layer 1 is made of an acrylate-based ionizing radiation curable composition. It is preferable that the refractive index thereof is close to that of a cured product of an acrylate-based ionizing radiation-curable composition, and from this point of view, the core portion and shell portion of the synthetic resin fine particles 3 are also made of an acrylic resin such as acrylic acid. It is preferable to use a polymer obtained by polymerizing an ester as a monomer, a polystyrene resin, that is, a resin obtained by polymerizing a styrene derivative as a monomer, or a polymer obtained by using an acrylic ester and a styrene derivative as a monomer in combination.

Methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, etc. can be used as the acrylate ester, and styrene, vinyltoluene, α-methylstyrene, etc. can be used as the styrene derivative. Of course, the above-mentioned monomers listed as the monomers capable of forming the ionizing radiation-curable composition for forming the hard coat layer can also be used in principle.

The core portion and the shell portion of the synthetic resin fine particles 3 may be made of the same synthetic resin or different synthetic resins, but the synthetic resin fine particles are dispersed in the hard coat layer, For the purpose of improving the hardness of the hard coat layer, the resin forming the core portion is harder than the resin forming the shell portion, in other words, the resin forming the core portion is It is preferable that the glass transition temperature is higher than that of the constituent resin. In order to raise the glass transition point, it is preferable that only the core portion is crosslinked or the crosslink density of the core portion is higher than that of the shell portion.

In order to improve the crosslink density, in addition to the above monomers, polyfunctional monomers such as acrylic acid esters (ethylene glycol diacrylate, 1,4-
Cyclohexane diacrylate, dipentaerythritol hexaacrylate, etc.), or methacrylic acid esters (ethylene glycol dimethacrylate,
Alternatively, pentaerythritol tetramethacrylate etc.) can be used. Of course, the above-mentioned compounds listed as the bifunctional or higher functional monomers capable of forming the ionizing radiation-curable composition for forming the hard coat layer can also be used here in principle as the polyfunctional monomer.

The synthetic resin fine particles 3 have a refractive index of 1.45 to 1.45.
If it is 1.59, it can be preferably used.

The relationship between the refractive index of the main synthetic resin constituting the hard coat layer 1 and the refractive index of the fine particles dispersed therein and the transparency is such that when the refractive index of the synthetic resin is lower than the refractive index of the fine particles. When the difference between the two refractive indexes is 0.05 or more, the transparency of the hard coat layer is lowered. For example, when the refractive index of the main synthetic resin is 1.50 and the refractive index of the fine particles is 1.55, the transparency is not good. However, when the refractive index of the synthetic resin is higher than the refractive index of the fine particles, and the difference between the two refractive indices is less than 0.9, the transparency of the hard coat layer is substantially reduced. When the refractive index is 1.53 and the refractive index of the fine particles is 1.45, the difference between the two refractive indexes is 0.08, and the transparency is good even though the difference is larger than in the previous example. is there. In addition, the quality of transparency referred to here is determined by a haze value,
Practically, it means that the difference with the haze value of the substrate is ± 0.5 when the transparent substrate is included.

The content Y (%) of the synthetic resin fine particles in the hard coat layer 1 may be small when the diameter X of the synthetic resin fine particles is large, and needs to be large when the diameter X is small. Further, when the diameter X of the synthetic resin fine particles is determined,
When the above content Y (%) is within a certain range,
The hardness of the hard coat layer can be improved, transparency can be maintained, and when the diameter X is small, the content ratio Y
Although the range of (%) is wide, the range of content ratio (%) becomes narrower as the diameter X increases.

According to the study by the inventor, the above effect can be exhibited when the content ratio Y (%) is −8.328.
6Ln (X) + 58.68 ≦ Y, and Y ≦ −1
It has been found that a compounding effect can be obtained when it is 6.934Ln (X) +118.68. The blending effect is determined by haze value for transparency, and practically, when accompanied by a transparent substrate, the difference from the haze value of the substrate is ± 0.5. Is determined to be transparent, and regarding the hardness, the radius of curvature r is 0.1 mm ≦ r ≦
In a scratch test using an indenter made of a substance having a hardness of 0.3 mm and a hardness of 200 Hv or more, it was judged to have a high hardness by not scratching when a load of 180 g was applied.

The hard coat layer 1 is applied onto the transparent substrate film by a known coating method using the above composition, and the coating film is cured by a means according to the composition used for the application. . When an ionizing radiation curable composition is used as the composition, ultraviolet rays or electron beams are selected and irradiated depending on the composition to crosslink and cure the coating film.

The thickness of the hard coat layer 1 in the present invention is preferably 0.5 to 30 μm, more preferably 3 to.
It is 15 μm. When the thickness of the hard coat layer 1 is too thin, sufficient hardness cannot be exhibited by itself, and when the various layers are formed thereon, the hardness of those layers cannot be maintained. However, flexibility decreases, and when various layers are laminated to form an antireflection film or the like, flexibility also decreases in the laminated state as a whole, and it takes time to cure when forming layers. This is because the production efficiency will decrease.

As shown in FIG. 2, the upper surface of the hard coat layer 1 is formed with unevenness 5 to scatter incident light of the display from the non-observation side (the transparent substrate 4 side in FIG. 2) and hard It is possible to reduce the occurrence of unnatural "glare" due to the increase in the brightness of a specific portion of the coat layer 1.

When forming the hard coat layer 1, the unevenness 5 is formed by allowing the coating film to be solidified while being coated with a patterning film having irregularities, or by applying a molding means such as a molding roll to the formed coating film. Alternatively, it can be formed by pressing while heating as necessary, or by coating and forming the hard coat layer 1 on a peelable substrate having unevenness on the peeling surface, and then peeling. The unevenness 5 has a height difference of 0.2 to 10 μm and a pitch of 20 to 200 μm.
m is good.

An antireflection film may be laminated on the hard coat layer 1 of the present invention to form an antireflection layer or an antireflection material with a transparent substrate. The antireflection film to be laminated is
It may be formed in a vapor phase such as vapor deposition or may be formed in a liquid phase by coating, and in any case, good adhesion can be obtained.

Generally, when the antireflection film is formed in the vapor phase, if there is a difference in elasticity between the antireflection film and the base, cracks are likely to occur in the antireflection film, and the antireflection film is reflected only on a hard coat layer that is only hard and brittle. When the anti-reflection film is formed, the hard coat layer does not follow the expansion and contraction of the anti-reflection film, and cracks may occur. However, in the hard coat layer 1 of the present invention, since the synthetic resin fine particles are used. The advantage is that it becomes easy to eliminate the difference in elasticity between the antireflection film and the hard coat layer 1.

When the antireflection film is formed in the liquid phase,
Adhesiveness can be improved by making the synthetic resin component forming the hard coat layer and the synthetic resin component forming the antireflection film the same or having common components with each other.

The antireflection film includes, for example, (1) a high-refractive index layer and a low-refractive index layer laminated in this order from the hard coat layer 1 side, (2) a high-refractive index layer, a low-refractive index layer. The layer, the high refractive index layer, and the low refractive index layer are sequentially laminated, or (3) the medium refractive index layer, the high refractive index layer, and the low refractive index layer are sequentially laminated. It may be something other than. The example of FIG. 3 is equivalent to a laminate of the high refractive index layer and the low refractive index layer of the above (1), and in the examples of (2) and (3), the antireflection film has four layers, respectively. It has a laminated structure of layers and three layers.

The high refractive index layer in (1) and (2) and the medium refractive index layer in (3) are made of ZnO and Ti.
O ₂ , CeO ₂ , Sb ₂ O ₅ , SnO ₂ , indium tin oxide, antimony-doped indium tin oxide, In ₂ O ₃ ,
_{Y 2 O 3, La 2 O} 3, Al 2 O 3, HfO 2, and ZrO ₂
It can be composed of a thin film made of a material selected from the group consisting of or a resin film in which ultrafine particles made of these materials are dispersed.

[0054] (1), (2), and (3) a low refractive index layer in a thin film made of SiO _2, SiO ₂ gel film or a fluorine-containing or fluorine and silicon-containing ultraviolet curable resin It can be composed of a cured film of the composition.

The high refractive index layer in (3) above is made of Fe,
Ni, Cr, Ti, Hf, Zn, Zr, Mo, and T
It can be composed of a metal thin film made of a metal selected from the group consisting of a or a resin film in which ultrafine particles made of these metals are dispersed.

The hard coat layer 1 of the present invention may have an antifouling layer 8 for preventing contamination on the outermost surface on the observation side. It is formed in order to prevent dirt and stains from adhering to the front surface of the coat layer 1 or to facilitate removal even if they adhere. Specifically, as long as the transparency of the hard coat layer 1 is not impaired, a surfactant such as a fluorinated surfactant, a paint containing a fluorinated resin, a release agent such as silicone oil, or a wax is applied very thinly. Then wipe off the excess. The antifouling layer 8 may be formed as a permanent layer,
It may be formed by coating whenever necessary. The thickness of the antifouling layer 8 is preferably about 1 to 10 nm.

The hard coat layer of the present invention can be made into an antiglare layer by blending an organic or inorganic filler (filler) in addition to the synthetic resin fine particles. Thus, when particles other than the synthetic resin fine particles are mixed, the shell portion of the synthetic resin fine particles has a function as a binder, so that the presence of the synthetic resin fine particles causes an organic or inorganic filler. There is an advantage that there is no problem in blending the (filler).

[0058]

[Example] (Example 1) DPHA as a resin-forming component
(Dipentaerythritol hexaacrylate, refractive index; 1.52) and acrylic synthetic resin fine particles (refractive index; 1.51, particle size; 150 nm) Mix so that the proportion is 20%, dilute the whole with toluene, and make the solid content 4
It was adjusted to 0% to obtain a hard coat layer-forming coating material. A high-transparency polyethylene terephthalate resin (= PE having a thickness of 188 μm and a surface subjected to an easy-adhesion treatment was prepared by adding an ultraviolet initiator to the above hard coat layer-forming coating material.
T) The surface of the film that has been subjected to the easy-adhesion treatment is applied by gravure coating, and after application, it is irradiated with ultraviolet rays to be cured,
A hard coat layer having a film thickness of 20 μm was formed.

On the formed hard coat layer, a TiO ₂ layer (thickness: 20 nm) and Si were formed by a sputtering method.
O ₂ layer (thickness; 40nm), TiO ₂ layers (thickness; 40n
m) and a SiO ₂ layer (thickness: 100 nm) were sequentially provided to form an antireflection film. Finally, the antireflection film was obtained by coating the antireflection film with a fluorine-containing surfactant to a thickness of 5 nm to form an antifouling layer.

Example 2 Polyfunctional urethane acrylate (refractive index: 1.51) as a resin-forming component, and acrylic synthetic resin fine particles (refractive index: 1.51, particle size: 100n)
m) was blended so that the mass ratio of the synthetic resin fine particles to the total mass of both was 30%, and thereafter the same procedure as in Example 1 was carried out to obtain an antireflection film.

Example 3 As a resin-forming component, a mixture (refractive index; 1.50) of polyfunctional silicon acrylate and DPHA in a mass ratio of 1/1, and acrylic synthetic resin fine particles (refractive index; 1. 51, particle size; 70 nm), and the ratio of the mass of the synthetic resin fine particles to the total mass of the two is 5
It was blended so as to be 0%, and thereafter the same procedure as in Example 1 was carried out to obtain an antireflection film.

Example 4 Polyfunctional epoxy acrylate (refractive index: 1.53) as a resin-forming component, and acrylic synthetic resin fine particles (refractive index: 1.51, particle size: 450)
nm) and 50% by weight of the synthetic resin fine particles in the total weight of the both are mixed, and thereafter the same procedure as in Example 1 is carried out to obtain an antireflection film.

Example 5 DPHA as a resin-forming component
And ZrO ₂ which is a high refractive index particle (refractive index; 1.76)
Mass ratio of 30% dispersion liquid of DPHA / ZrO ₂ 30
% Dispersion = 66/34 mixture (refractive index; 1.60)
And styrene-acrylic synthetic resin fine particles (refractive index;
1.59, particle size; 600 nm) so that the ratio of the mass of the synthetic resin fine particles to the total mass of the both is 5%, and thereafter the same procedure as in Example 1 is carried out to obtain the hard coat layer. Was formed. A TiO ₂ layer (thickness: 120 nm), Si was formed on the hard coat layer by a sputtering method.
An O ₂ layer (thickness: 100 nm) is provided in order to form an antireflection film, and a fluorine-based surfactant is further coated on the antireflection film to a thickness of 5 nm to form an antifouling layer to prevent reflection. I got a film.

The hard coat layer in Example 5 was
Since there is almost no difference in the refractive index between the fine particles in the layer and the binder, it is highly transparent and suitable for use in optical applications. Further, since the hard coat layer has a high refractive index, the anti-reflection film can be formed by laminating two layers.
The average reflectance is 1 for light in the range of 0 nm to 650 nm.
An excellent antireflection property of less than 10% is obtained.

Example 6 DPHA as a resin-forming component
And high refractive index particles of TiO ₂ (refractive index; 1.90)
Mass ratio of 30% dispersion liquid of DPHA / TiO ₂ 30
% Dispersion = 66/34 mixed solution (refractive index; 1.65)
And styrene-acrylic synthetic resin fine particles (refractive index;
1.59, particle size; 20 nm) so that the ratio of the mass of the synthetic resin fine particles to the total mass of the both becomes 50%, and thereafter, the same procedure as in Example 1 is carried out to perform the hard coat layer. After that, an antireflection film and an antifouling layer were formed in the same manner as in Example 5 to obtain an antireflection film. Since the hard coat layer in this Example 6 has a high refractive index, the antireflection film, like the film obtained in Example 5, can be formed by laminating two layers to obtain a thickness of 450 nm.
An excellent antireflection property with an average reflectance of less than 1% is obtained for light in the range of 650 nm.

(Example 7) DPHA and acrylic synthetic resin fine particles (refractive index; 1.51, particle diameter; 130 nm) accounted for 40% of the total mass of the synthetic resin fine particles. And the same procedure as in Example 1 to obtain a film thickness of 2 by gravure coating.
After coating so that the thickness becomes 0 μm, the matte surface of the matte-treated PET film is overlaid and adhered onto the coated film, and the coating film is cured by irradiating ultraviolet rays through the PET film and then PET. The film was peeled off to form a hard coat layer having fine irregularities on the surface. On the hard coat layer thus formed, in the same manner as in Example 1,
An antireflection film and an antifouling layer were formed to obtain an antireflection film.

(Comparative Example 1) A hard coat layer, an antireflection film, and an antifouling agent were prepared in the same manner as in Example 1 except that DPHA was used alone as the solid content and no acrylic synthetic resin particles were added. The layers were sequentially formed to obtain an antireflection film. The obtained antireflection film has a strong curl and cannot be measured, and although the hard coat layer has hardness,
It was easily cracked and had a poor scratch hardness.

Comparative Example 2 DPHA / H as solid content
An antireflection film was obtained in the same manner as in Example 1, except that the acrylic synthetic resin fine particles were not blended and the mass ratio of DDA was 8/2. HDDA
Refers to 1,6-hexanediol diacrylate.
The obtained antireflection film was improved in curl as compared with that of the comparative example, but the measured curl was 70.
mm, and more flexible than that obtained in Comparative Example 1, but cracks occurred and scratch hardness was slightly inferior.

COMPARATIVE EXAMPLE 3 DPHA and acrylic synthetic resin fine particles (refractive index: 1.51, particle size: 250 nm) accounted for 50% of the total mass of the synthetic resin fine particles. After that, the same procedure as in Example 1 was performed to obtain an antireflection film. The obtained anti-reflection film had a good curl measurement value of 20 mm, but since the acrylic synthetic resin fine particles were excessive,
The scratch hardness was considerably inferior.

Comparative Example 4 The same polyfunctional silicone acrylate / DPHA = 1/1 mixture (refractive index: 1.50) used in Example 3 and styrene-acrylic synthetic resin fine particles (refractive index) were used. 1.59, particle size; 150 nm) so that the ratio of the mass of the synthetic resin fine particles to the total mass of the both is 30%, and thereafter, the same procedure as in Example 1 is performed to prevent reflection. I got a film. The obtained antireflection film has a large difference in refractive index between the matrix resin and the synthetic resin particles in the hard coat layer.
In the laminated state of the PET film and the hard coat layer, the haze value is 0.7 that of the PET film alone.
However, the transparency was not good.

(Comparative Example 5) DPHA as a resin-forming component
And solid content 30% colloidal silica (MEK dispersion liquid, refractive index; 1.45) were blended so that the latter was 70% of the total mass of both, to give an ink having a solid content of 38%.
After the hard coating layer was formed in the same manner as in Example 1, the antireflection film and the antifouling layer were formed in the same manner as in Example 1 to obtain an antireflection film. Although the curl of the colloidal silica used tended to become smaller as the compounding amount was increased, the obtained antireflection film had a large curl measurement value of 65 mm and had a poor scratch strength.

The above Examples 1 to 7 and Comparative Examples 1 to 5
The results of evaluating the transparency, curl, and scratch strength of the antireflection film obtained in (1) are shown in "Table 1". Transparency is determined visually. The curl was defined as the value of "curl" with the height of the highest portion of the antireflection film from the reference surface when the antireflection film was placed on a reference plane with a size of 15 cm x 20 cm. The scratching strength is such that the radius of curvature X is 0.1 mm ≦ X
≤0.3 mm, hardness Y is 200 Hv ≤ Y, a load is applied to a metal indenter, and it is obtained by scratching from the antifouling layer, provided that 5 scratch lines are formed with the same load,
After standing at room temperature for 1 day, the CRT screen was brought into a bright yellow-green display state, an antireflection film was attached, and a load value at which 3 of the 5 scratch lines was judged to be scratch-free was defined as scratch strength.

[0073]

[Table 1]

[0074]

According to the first aspect of the present invention, a filler having a core-shell structure and having a defined glass transition temperature relationship between the core portion and the shell portion is used as the filler for increasing the hardness. It is possible to provide a hard coat layer having high transparency while having the above. According to the invention of claim 2, in addition to the effect of the invention of claim 1, the relationship between the particle diameter of the fine particles having the core-shell structure and the compounding ratio is defined.
It is possible to provide a hard coat layer that can further satisfy high hardness and transparency. According to the invention of claim 3, in addition to the effect of the invention of claim 1 or 2, since only the core part is crosslinked or the core part has a higher crosslink density than the shell part, Is hard, and therefore the hardness of the coating film is improved, and since the shell portion is more flexible than the core portion, it is possible to provide a hard coat layer that does not impair the flexibility of the coating film. According to the invention of claim 4, claim 1
In addition to the effect of the invention of any one of claims 3 to 3, it has a surface unevenness, so that it is possible to provide a hard coat layer that can alleviate that the light from the back surface is concentrated in one place and is felt bright. According to the invention of claim 5, claims 1 to
In addition to the effect of the invention of claim 4, it is possible to provide a hard coat layer in which the antireflection film is sufficiently adhered to the hard coat layer. Such a hard coat layer with an antireflection film can exhibit high hardness of the surface as well as antireflection properties. According to the invention of claim 6, in addition to the effect of the invention of any one of claims 1 to 5, since the antifouling layer is laminated on the outermost surface, the surface is hardly soiled, and even if soiled, it can be wiped off. It is possible to provide a hard coat layer that is easy to clean by such means. According to the invention of claim 7, since the hard coat layer according to any one of claims 1 to 6 is laminated on the transparent base material, each effect is exerted, and since the base material has the base material, various effects can be obtained. It is possible to provide a hard coat material suitable for being applied to the above uses. According to the invention of claim 8, the hard coat layer according to any one of claims 1 to 6 or the hard coat material according to claim 7 is arranged on the viewing side of a display device such as a liquid crystal display device. It is possible to provide a display device in which the brightness is not lowered due to the above-mentioned processing and the surface hardness of the arranged display device is high.

[Brief description of drawings]

FIG. 1 is a view of a hard coat layer and a hard coat material of the present invention.

FIG. 2 is a diagram of a hard coat material having irregularities on its surface.

FIG. 3 is a view of a hard coat material having a surface antireflection film and an antifouling layer.

FIG. 4 is a diagram showing a state of being applied to a display device.

[Explanation of symbols]

1 Transparent hard coat layer 2 synthetic resin 3 Synthetic resin particles 4 Transparent base material 7 Antireflection film 8 Antifouling layer 10 Liquid crystal display device 11 LCD panel 12 Light guide plate 14 Reflector

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H091 FA37X FB02 FB06 FC23                       GA16 KA01 LA02 LA16 LA30                 4F100 AA20 AA21 AK01A AK25                       AK42 AR00C AS00A AT00D                       BA01 BA02 BA03 BA04 BA05                       BA07 BA10B BA10C BA10D                       CC00A DD01A DD07A DE01A                       EH46 EH66 EJ05A GB41                       JA05A JB14 JK12 JK12A                       JL06C JM02B JN01 JN01A                       JN01D JN06 JN06B YY00A                 4J038 CC022 CG142 DB001 FA011                       FA041 FA111 FA112 FA221                       MA03 MA13 NA11 NA19 PA17                       PB08 PC08

Claims (8)

[Claims] 1. A synthetic resin fine particle having a core-shell structure having a glass transition temperature of the core portion higher than that of the shell portion is formed of a dispersion film dispersed in a binder made of a crosslinked synthetic resin. Transparent hard coat layer. 2. The average particle size X of the synthetic resin particles and the mass-based content Y (%) of the synthetic resin particles in the dispersion film have a relationship represented by the following formula: The transparent hard coat layer according to claim 1. −8.3286Ln (X) + 58.68 ≦ Y ≦ −16.
934Ln (X) +118.68 3. The synthetic resin particles, wherein the core portion is crosslinked and the shell portion is not crosslinked, or the core portion has a higher crosslink density than the shell portion. The transparent hard coat layer according to claim 1 or 2. 4. The transparent hard coat layer according to claim 1, which has fine irregularities on its surface. 5. The transparent hard coat layer according to any one of claims 1 to 4, wherein an antireflection film is laminated on the surface. 6. The transparent hard coat layer according to claim 1, wherein an antifouling layer is laminated on the outermost surface. 7. A transparent hard coat material, wherein the hard coat layer according to any one of claims 1 to 6 is laminated on a transparent base material. 8. A display device, wherein the transparent hard coat layer according to any one of claims 1 to 6 or the transparent hard coat material according to claim 7 is disposed on an observation side of a display device.