JP6778716B2 - Hard coat film - Google Patents

Description

The present invention relates to a coating composition for a hard coat film and a hard coat film, and is particularly suitable as a surface base material for various display devices such as a liquid crystal display device, a CRT display device, a plasma display device, and an EL display device. Regarding the composition and the hard coat film.

Conventionally, in order to protect the surface of a display screen of a liquid crystal display device, a plasma display device, etc., and to prevent the surface from being difficult to see due to glare caused by reflection of external light on the display screen, the surface has an uneven shape. A transparent polymer hard coat film having the above has been used. In general, such a polymer film is provided with a hard coat layer which contains particles serving as a matting agent and is subjected to unevenness treatment.

For example, Patent Document 1 discloses an antiglare film in which an antiglare layer (transparent hard coat layer) containing two types of translucent fine particles having different particle diameters is laminated in a translucent resin. Here, the refractive index of the first translucent fine particles is 0.04 to 0.20 larger than the refractive index of the translucent resin, and the difference in refractive index between the second translucent fine particles and the translucent resin. Is 0.3 or less, and the second translucent fine particles have a particle diameter larger than that of the first translucent fine particles, and may project 0.1 to 0.3 μm from the surface of the antiglare layer. Are listed. It has also been shown that the particle size of the second translucent fine particles is made larger than the film thickness of the antiglare layer.
Further, it is described that the antiglare film having the above structure can improve the transmission clarity and reduce the glare without lowering the diffusion / antiglare property. However, the effect of preventing the glare phenomenon of the antiglare film of Patent Document 1 is not yet sufficient.

Patent Document 2 describes an antiglare coating composition which is applied on a transparent base material to form an antiglare layer, wherein the antiglare coating composition contains a first component and a second component, and the antiglare coating is provided. After the composition is applied onto the substrate, the first component and the second component are phase-separated based on the difference in physical properties of the first component and the second component, and a resin layer having random irregularities on the surface is formed. Antiglare coating compositions are disclosed. Here, the first component is an oligomer or resin which is an unsaturated double bond-containing acrylic copolymer, the second component is a polyfunctional unsaturated double bond-containing monomer, and the SP value of the first component (SP _1). ) And the SP value (SP ₂ ) of the second component are described to satisfy SP ₁ <SP ₂ .
Further, it is shown that in the coating composition having the above structure, a resin layer having irregularities is formed even if it does not contain resin particles or the like, so that an antiglare film having improved reflection, white blur, etc. can be obtained. Has been done.

In recent years, the color screens of various display devices have been remarkably improved in definition. Then, when a transparent hard coat layer in which an uneven shape is formed by a conventional method using a matting agent is installed on the screen of a high-definition color display or the like, the matting agent particles become bright spots and the color image is glaring. The problem of visibility (hereinafter referred to as the "glare phenomenon") has come to occur.
In order to prevent this glare phenomenon, it is effective to reduce the particle size of the matting agent particles. However, as in Patent Document 1, when unevenness is formed by projecting the matting agent particles, it is necessary to reduce the particle size of the matting agent particles and at the same time reduce the thickness of the hard coat film. When the hard coat film is thinned in this way, sufficient hardness and scratch resistance cannot be obtained, and a decrease in antiglare property due to an increase in gloss becomes a problem. On the other hand, when the hard coat film is thickened in order to obtain sufficient hardness, the particles are buried inside the film without being arranged on the film surface, and unevenness is not formed on the surface, so that the gloss is increased and the antiglare property is improved. I can't get it.
Further, as in Patent Document 2, when an antiglare layer having irregularities formed on the surface is installed on a high-definition color display without using particles such as a matting agent, both antiglare and suppression of glare phenomenon are achieved. It is difficult to make it, and no material that satisfies both of these performances has been obtained.
As described above, at present, a hard coat film having sufficient hardness, excellent antiglare and transparency, and capable of preventing glare even when used in a high-definition color display has not been obtained.

Japanese Patent No. 4651705 (claim) Japanese Patent No. 3989697

Therefore, an object of the present invention is a coating composition for a hard coat film, which has high hardness, is excellent in antiglare and transparency, and can prevent a glare phenomenon even when used for a high-definition color display. It is to provide a coat film.

As a result of diligent research in view of the above problems, the present inventor has obtained a hard coat film obtained from a coating composition containing two types of resin components having a predetermined SP value difference and particles having a predetermined particle size distribution. We have found that the above problems can be solved and came up with the present invention. That is, the coating composition for a hard coat film of the present invention is a coating composition for a hard coat film containing a resin component and particles, and the resin component contains at least (A) an ionizing radiation curable oligomer or a monomer (B). ) (A) Contains a resin component whose difference from the SP value of the component is 1.0 (cal / cm ³ ) ^1/2 or more and less than 3.0 (cal / cm ³ ) ^1/2 , and the particles have a particle size distribution. However, it is characterized by containing particles satisfying the relationships of D50 = 0.5 μm to 1.5 μm, D90 = 1.5 μm to 4.0 μm, and D90-D50 = 1 to 3.5.
Further, the present inventor solves the above problem with a hard coat film containing two kinds of resin components having a predetermined SP value difference and satisfying a predetermined relationship between the average particle diameter of the particles and the average thickness of the hard coat film. I found out what I could do. That is, the hard coat film of the present invention is a hard coat film containing a resin component and particles, and the resin component is at least the SP value of (A) ionizing radiation curable oligomer or monomer and (B) (A) component. It is formed from a resin component whose difference from 1.0 (cal / cm ³ ) ^1/2 or more and less than 3.0 (cal / cm ³ ) ^1/2 , and the average particle size of the particles is that of the hard coat film. It is characterized by being 5% to 30% of the average thickness.

The content of the component (B) in the coating composition for a hard coat film of the present invention is preferably 1% by mass to 5% by mass, with the total resin component of the coating composition as 100.
Further, it is preferable that the particles in the coating composition for a hard coat film of the present invention have one peak in the particle size distribution of 0.1 μm or more.
Further, it is preferable that the SP value (SP1) of the component (A) and the SP value (SP2) of the component (B) satisfy SP1 <SP2.
The component (A) is preferably a polyfunctional urethane (meth) acrylate oligomer having an energy ray (ionizing radiation) curable functional group number in the range of 6 to 20, and the component (B) is an acetal resin. Is preferable.
The component (B) is preferably a resin having a glass transition temperature of 90 ° C. or higher and having one or more OH groups.

The average thickness of the hard coat film of the present invention is preferably 0.5 μm to 10 μm.
Further, the particles contained in the hard coat film of the present invention preferably have a refractive index difference of 0.03 to 0.10.
The hard coat film of the present invention further contains inorganic fine particles having an average particle diameter of primary particles of 5 nm to 50 nm, and the inorganic fine particles preferably have a refractive index difference of 0.03 or more from the resin component.
The content of particles in the hard coat film of the present invention is preferably 1% by mass to 10% by mass, with the total mass of the hard coat film as 100, and the content of inorganic fine particles is the total mass of the hard coat film. Is 100, and it is preferably 1% by mass to 12% by mass.
The arithmetic mean roughness (Ra) of the hard coat film of the present invention according to JIS B0601 is preferably 0.05 μm or more and less than 0.20 μm.

INDUSTRIAL APPLICABILITY According to the present invention, a hard coat film having high hardness, excellent antiglare and transparency, and capable of preventing a glare phenomenon even when used for a high-definition color display can be obtained.

It is a graph which shows an example of the relationship between the haze of the hard coat film of the prior art and the present invention, and a 60 degree mirror surface gloss. It is sectional drawing which shows an example of the structure of a touch panel.

Embodiment of the invention

Embodiments of the present invention will be described in detail below.

(1) Coating Composition for Hard Coat The coating composition for a hard coat film of the present invention is a coating composition for a hard coat film containing a resin component and particles, and the resin component is at least (A) ionizing radiation curing. The difference between the sex oligomer or monomer and the SP value of the components (B) and (A) is 1.0 (cal / cm ³ ) ^1/2 or more and less than 3.0 (cal / cm ³ ) ^1/2. The particles are characterized by containing particles having a particle size distribution satisfying the relationships of D50 = 0.5 μm to 1.5 μm, D90 = 1.5 μm to 4.0 μm, and D90-D50 = 1 to 3.5. To do.
The details of the coating composition for a hard coat film of the present invention will be described below.

In the coating composition for a hard coat film of the present invention, the difference between the SP values of the (A) ionizing radiation curable oligomer or monomer and the (B) and (A) components is 1.0 (cal / cm ³ ) ^1/2 or more. , 3.0 (cal / cm ³ ) less than ^1/2 of the resin component and particles, and other ionizing radiation curable monomers, inorganic fine particles, leveling agent, photopolymerization initiator different from the component (A) , Photopolymerization initiator, solvent and the like can be added to prepare the mixture.
The details of each component will be described below.

[(A) component]
The (A) ionizing radiation curable oligomer or monomer of the present invention is the main component of the hard coat film and is used to form a film having high hardness and flexibility. As the component (A), a monomer such as a polyfunctional monomer, a (meth) acrylic resin, an olefin resin, a polyether resin, a polyester resin, a polyurethane resin, a polysiloxane resin, a polysilane resin, a polyimide resin, or a fluorine resin is used as a skeleton structure. Containing oligomers can be used.
Among the above, it is preferable to use a polyfunctional urethane (meth) acrylate oligomer or monomer having 6 to 20 functional groups. By using such a polyfunctional urethane (meth) acrylate oligomer or monomer, the crosslink density of the film is increased, and the substrate protection performance such as hardness and scratch resistance required for the hard coat film can be obtained. Further, by using the above-mentioned oligomer or monomer, a film having high flexibility and flexibility and excellent workability can be obtained, so that the occurrence of cracks in a processing process such as punching can be suppressed.
By setting the number of ionizing radiation curable functional groups of the polyfunctional urethane (meth) acrylate oligomer or monomer to 6 or more, the hardness of the film is sufficiently increased, so that the scratch resistance is improved. On the other hand, the number of functional groups of the polyfunctional urethane (meth) acrylate oligomer or monomer is preferably 20 or less, more preferably 16 or less. As a result, it is possible to suppress steric hindrance due to an excessive increase in the crosslink density and prevent a decrease in hardness due to hardening inhibition.
The content of the component (A) is preferably 70% by mass to 99% by mass, more preferably 80% by mass to 95% by mass, with the total resin component in the coating composition as 100. By setting the content of the component (A) within the above range, a hard coat film having further excellent substrate protection properties and processability can be obtained.

The urethane (meth) acrylate is a reaction product of an isocyanate compound obtained by reacting a polyol with a diisocyanate and a (meth) acrylate monomer having a hydroxyl group. Examples of the polyol include polyester polyol, polyether polyol, polycarbonate diol and the like. These may be used alone or in combination of two or more. In addition, (meth) acrylate means acrylate or methacrylate.

The method for producing the polyester polyol used for producing the urethane (meth) acrylate oligomer or the monomer is not particularly limited, and a known production method can be used. For example, the diol may be polycondensed with a dicarboxylic acid or a dicarboxylic acid chloride, or the diol or dicarboxylic acid may be esterified and subjected to a transesterification reaction. Examples of the dicarboxylic acid include adipic acid, succinic acid, glutaric acid, pimelic acid, sebacic acid, azelaic acid, maleic acid, terephthalic acid, isophthalic acid, and phthalic acid. Examples of the diol include ethylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, tripropylene glycol, and tetrapropylene glycol. These may be used alone or in combination of two or more.

The polyether polyol is preferably a polyethylene oxide, polypropylene oxide, or ethylene oxide-propylene oxide random copolymer having a number average molecular weight of less than 600. When the number average molecular weight is 600 or more, the cured product is flexible, so that sufficient hard coating performance may not be obtained.

Examples of the polycarbonate diol include 1,4-butanediol, 1,6-hexanediol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, dipropylene glycol, and 2 -Ethyl-1,3-hexanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanediol, polyoxyethylene glycol and the like can be mentioned. These may be used alone or in combination of two or more.

As the diisocyanate, a linear type or a cyclic type aliphatic diisocyanate can be used. In addition, aromatic diisocyanate can also be used. Examples of the linear or ring-type aliphatic diisocyanate include hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated xylylene diisocyanate. These may be used alone or in combination of two or more.

[(B) component]
As the component (B), a resin component whose difference from the SP value of the component (A) is 1.0 (cal / cm ³ ) ^1/2 or more and 3.0 (cal / cm ³ ) ^{1/2 or} less is used. Use. Here, the SP value is a solubility parameter (Solubility Parameter), and is a parameter indicating affinity. The two components having similar SP values have a high affinity and are easily mixed (high solubility), while the two components having different SP values have a low affinity and are difficult to mix (low solubility).
As the component (B), a resin having a difference from the SP value of the component (A) of 1.0 (cal / cm ³ ) ^1/2 or more and 3.0 (cal / cm ³ ) ^{1/2 or} less is used. As a result, undulations occur due to appropriate phase separation between the components (A) and (B) during film formation, irregularities are formed on the film surface, and a hard coat film having a structure in which particles are arranged along the undulations on the film surface. Is obtained.
Therefore, by using the coating composition for a hard coat film of the present invention, the particles can be arranged on the surface even when the particles having a particle diameter smaller than the thickness of the hard coat film are used. Therefore, unlike the conventional hard coat film in which particles are projected on the film surface to form irregularities, it is not necessary to use matte particles having a particle diameter sufficiently larger than the film thickness. Therefore, in the coating composition for a hard coat film of the present invention, particles having a fine particle size effective for preventing the glare phenomenon of a high-definition color display can be added, and sufficient hardness can be obtained as a hard coat film. It can be adjusted to a film thickness. As described above, by using the coating composition for a hard coat film of the present invention, the hard coat film has high hardness, excellent antiglare property, and can suppress the glare phenomenon even when used for a high-definition color display. Is obtained.
If the difference between the SP values of the component (A) and the component (B) is less than 1 (cal / cm ³ ) ^1/2 , the affinity between the two is high, so that undulations due to phase separation are not sufficiently formed, and the particles are formed on the film surface. The effect of arranging in is unlikely to occur. Therefore, the surface of the obtained hard coat film becomes flat, and sufficient antiglare property cannot be obtained. On the other hand, when the difference between the SP values of the component (A) and the component (B) exceeds 3 (cal / cm ³ ) ^1/2 , the affinity between the two is low, and the film surface becomes rough due to phase separation, resulting in surface roughness. Will be higher. For this reason, it is not possible to support a high-definition color display, and sufficient transparency cannot be obtained due to an increase in haze.

The content of the component (B) is preferably 1% by mass to 5% by mass, more preferably 2% by mass to 4% by mass, with the total resin component in the coating composition as 100. By setting the content of the component (B) within the above range, the particles can be arranged on the film surface more effectively, and a hard coat film having more excellent antiglare properties can be obtained.

As described above, the difference between the SP value (SP1) of the component (A) and the SP value (SP2) of the component (B) is 1.0 (cal / cm ³ ) ^1/2 or more, 3.0 (cal / cm). ³ ) Although the effect of the present invention can be obtained by setting it to less than ^1/2 , it is preferable that SP1 <SP2. A coating composition (coating liquid) in which the SP value (SP1) of the component (A), which is the main component, is lowered to obtain a resin having a low polarity, and the component (B) having a high SP value and a high polarity is dispersed therein. Prepare. By curing such a coating composition, the particles are more easily arranged on the film surface due to the phase separation of the component (A) and the component (B). As a result, a hard coat film having further excellent antiglare properties can be obtained.

The type of the component (B) is not particularly limited as long as it is a resin component other than the component (A) having the above SP value. For example, polyester acrylate resin, polyurethane acrylate resin, epoxy acrylate resin, polyester resin, acrylic resin, polycarbonate resin, epoxy resin, cellulose resin, acetal resin, vinyl resin, polyethylene resin, polystyrene. Thermoplastic resins such as based resins, polypropylene-based resins, polyamide-based resins, polyimide-based resins, melamine-based resins, phenol-based resins, silicone-based resins, and fluorine-based resins, and thermosetting resins can be used. It is preferable to use a thermoplastic resin from the viewpoint that the surface shape can be easily adjusted and the handleability is excellent.
The glass transition temperature (Tg) of the component (B) is preferably 90 ° C. or higher. By using a resin having a high glass transition temperature as described above, a hard coat film having excellent heat resistance can be obtained. This makes it possible to prevent problems such as a decrease in scratch resistance and an increase in haze due to heat whitening, which may occur due to the influence of a dispersant or the like when heat treatment is conventionally performed in the film forming process. Normally, when the component (B) having a high Tg is used, the solubility with the component (A) decreases, but in the present invention, by adding the ionizing radiation curable monomer described later, the component (A) and ( B) Solubility with components can be improved.
Further, the component (B) is preferably a resin having one or more OH groups. As a result, cross-linking proceeds in the film forming process, and the hardness of the film can be further improved.
As the component (B), an acetal resin is preferable, and among them, a polyvinyl acetal resin, a polyvinyl butyral resin, a polyvinyl formal resin and the like are preferable.

(Ionizing radiation curable monomer)
An ionizing radiation curable monomer (photopolymerizable monomer) different from the component (A) can be added to the coating composition of the present invention. Examples of the photopolymerizable monomer include monofunctional acrylic monomers such as 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate and butoxyethyl acrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate and diethylene glycol. At least one of bifunctional acrylic monomers such as diacrylate, polyethylene glycol diacrylate and hydroxypivalic acid ester neopentyl glycol diacrylate, and polyfunctional acrylic monomers such as dipentaerythritol hexaacrylate, trimethylpropanetriacrylate and pentaerythritol triacrylate. Can be used. By adding these, the hardness of the hard coat film can be further improved.
Further, as described above, the component (B) (dispersed resin) having a high glass transition temperature usually has low solubility in the ionizing radiation curable oligomer or monomer which is the component (A). Here, by adding the photopolymerization monomer, it functions as a cushioning agent for the component (A) and the component (B), and by improving the solubility of both, a uniform coating composition can be obtained. ..
The content of the photopolymerizable monomer is preferably 5% by mass to 30% by mass, more preferably 10% by mass to 25% by mass, with the total resin component in the coating composition as 100. By setting the content of the photopolymerizable monomer within the above range, the solubility of the components (A) and (B) and the hardness of the obtained film can be further improved.

(particle)
The coating composition for a hard coat film of the present invention has a particle size distribution of D50 = 0.5 μm to 1.5 μm, preferably D50 = 0.6 μm to 1.4 μm, D90 = 1.5 μm to 4.0 μm, and D90. It contains particles that satisfy the relationship of −D50 = 1 to 3.5. As described above, in the present invention, when the coating composition is formed into a film, undulations are formed on the film surface due to the phase separation of the components (A) and (B), and the particles are arranged on the film surface. Then, an uneven shape of a structure in which the particles are arranged along the swell of the film surface is formed.
Here, by defining the particle size distribution of the particles in the coating composition as described above, a hard coat film capable of effectively preventing the glare phenomenon can be obtained even when the particles are installed in a high-definition color display. Further, by using fine particles in the above range, an increase in haze can be suppressed and a highly transparent hard coat film can be obtained. When the particle size distribution D50 of the particles in the coating composition of the present invention is less than 0.5 μm , Anti-glare (anti-reflection) is not sufficient. On the other hand, when D50 exceeds 1.5 μm, when it is installed in a high-definition color display, a sufficient effect of preventing the glare phenomenon cannot be obtained, and the transparency is lowered due to the increase in haze.
Further, if the particle size distribution D90 of the particles in the coating composition of the present invention is less than 1.5 μm, the uneven shape required for obtaining the antiglare performance cannot be obtained. On the other hand, if the D90 exceeds 4.0 μm, when it is installed in a high-definition color display, a sufficient effect of preventing the glare phenomenon cannot be obtained, and the transparency is lowered due to the increase in haze.
Further, when the particle size distribution D90-D50 of the particles in the coating composition of the present invention is less than 1 μm, the particles are too uniform in size, so that a sufficient effect of preventing the glare phenomenon cannot be obtained. On the other hand, when D90-D50 exceeds 3.5 μm, a sufficient effect of preventing the glare phenomenon cannot be obtained due to the influence of coarse particles.
The particle size distribution of the particles is the particle size distribution in the coating composition before curing, and can be adjusted by adding the particles to the coating composition and then dispersing them. As a specific dispersion method, a bead mill, a ball mill, a sand mill, an attritor, a roll mill, a jet mill, a homogenizer, a paint shaker, a kneader, an agitator, a Henschel mixer, a colloid mill and the like can be used.
Further, as will be described later, in order to improve the dispersion stability, inorganic fine particles finer than the above particles may be added, but here, the particle size of the particles involved in forming the uneven shape of the film surface is defined. .. The particle size distribution of the particles in the coating composition can be measured by a laser diffraction type particle size distribution measuring device or the like as described later. Here, by setting the lower limit value of the measurement particle size range to 0.1 μm or more, the value of the inorganic fine particles can be omitted, and the particle size distribution of the particles involved in the formation of irregularities on the film surface can be calculated.
It is preferable that there is only one peak in the particle size distribution of particles having a size of 0.1 μm or more, which is involved in the formation of irregularities on the film surface. By making the particles involved in the formation of unevenness in this way, an excellent effect of preventing the glare phenomenon can be obtained.

Further, the particles preferably have a refractive index such that the difference from the refractive index of the resin component of the hard coat film after curing is 0.03 to 0.10. By projecting particles having a refractive index in the above range onto the film surface, optical interference occurs more effectively, and a further excellent antiglare effect can be obtained.
As the particles, organic particles and inorganic particles can be used. Specific examples of the material of the organic particles include acrylic, polyester, polystyrene, polycarbonate, polyvinyl chloride, and the like. On the other hand, examples of the material of the inorganic particles include silica, alumina, talc, clay, calcium carbonate, magnesium carbonate, barium sulfate, aluminum hydroxide, titanium dioxide, zirconium oxide and the like. It is preferable to select from these in consideration of the refractive index of the resin component used. As long as the particles have the above particle size distribution, they can be used alone or in combination of two or more. From the viewpoint of suppressing the glare phenomenon, it is preferable to use inorganic particles. Furthermore, in order to obtain the better effect of the present invention, it is preferable to use silica as the particles.
Further, as the particles, organic / inorganic composite particles in which the surface of the organic particles is coated with an inorganic layer can also be used. As the inorganic layer, silica, alumina, zirconia, a composite material thereof, or the like can also be used. Further, as the particles, hollow particles such as hollow glass beads, hollow silica beads, and hollow acrylic beads can also be used.

In the present invention, the coating composition is such that the total mass of the cured hard coat film is 100 and the particle content is 1% by mass to 10% by mass, preferably 1.5% by mass to 7% by mass. It is preferable to add particles inside. By setting the content of the particles in the above range, a hard coat film having further excellent antiglare property and transparency can be obtained.

(Inorganic fine particles)
In addition to the particles, inorganic fine particles may be added to the coating composition of the present invention for the purpose of imparting thixotropy to the coating composition and enhancing the dispersion stability of the particles and resin components. The average particle size of the primary particles of the inorganic fine particles is 5 nm to 50 nm, the difference in the refractive index between the inorganic fine particles and the resin component of the hard coat film after curing is 0.03 or more, and the refractive index between the inorganic fine particles and the particles. The difference is preferably 0.03 or less. By setting the average particle size of the primary particles of the inorganic fine particles in the above range, the inorganic fine particles can be easily dispersed uniformly in the coating composition, and the coating composition can be effectively imparted with thixophilicity. As a result, the dispersibility of the particles and the resin component in the coating composition can be maintained, and the coating characteristics of the coating composition can be improved.
Further, by setting the refractive index of the inorganic fine particles within the above range, gloss can be suppressed by a light scattering effect, antiglare can be improved, haze of the film can be suppressed from rising, and transparency can be maintained. ..
Specific examples of the inorganic fine particles include silica, alumina, talc, clay, calcium carbonate, magnesium carbonate, barium sulfate, aluminum hydroxide, titanium dioxide, zirconium oxide and the like. It is preferable to select from these in consideration of the resin component to be used, the refractive index of the particles, and the like. Inorganic fine particles having the above average particle size and refractive index can be used alone or in combination of two or more. In order to obtain a better effect as the inorganic fine particles, it is preferable to use silica.
The inorganic fine particles are added to the coating composition so that the content of the inorganic fine particles is 1% by mass to 12% by mass, and further 3 to 12% by mass, assuming that the mass of the entire hard coat film after curing is 100. Is preferable. By setting the content of the inorganic fine particles in the above range, the coating characteristics of the coating composition can be improved, and the transparency of the obtained hard coat film can be maintained.

(Photopolymerization initiator)
When the ionizing radiation curable oligomer or monomer which is the component (A) is cured by ultraviolet rays, it is preferable to add a photopolymerization initiator. Examples of the photopolymerization initiator include benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether and benzoin isobutyl ether, acetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-. Dichloroacetophenone, 2-hydroxy-2-methyl-phenylpropan-1-one, diethoxyacetophenone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopro Acetophenones such as pan-1-one, anthraquinones such as 2-ethylanthraquinone, 2-t-buterantraquinone, 2-chloroanthraquinone, 2-amylanthraquinone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2 -Thioxanthones such as chlorothioxanthone, acetophenone dimethyl ketal, ketals such as benzyl dimethyl ketal, benzophenone, 4-benzoyl-4'-methyldiphenylsulfide, benzophenones such as 4,4'-bismethylaminobenzophenylone. Examples thereof include phosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide. These may be used alone or in combination of two or more.

(Photopolymerization initiator)
It is preferable to add a photopolymerization initiator to the coating composition of the present invention. By adding a photopolymerization initiator, it is possible to prevent oxygen inhibition from occurring on the surface of the cured product when the coating composition of the present invention is cured by irradiation with ionizing radiation, so that curing with higher hardness is possible. You can get things. Examples of such a photopolymerization initiator include amine compounds, carboxylic acid compounds, and polyfunctional thiol compounds. The photopolymerization initiator may be used alone or in combination of two or more. In order to improve the efficiency of the radical polymerization reaction, it is preferable to use a polyfunctional thiol compound.

(Leveling agent)
Further, by adding a leveling agent to the coating composition for a hard coat film, a smoother and more uniform hard coat film can be obtained. As the leveling agent, a modified silicone compound, a fluorine compound, an acrylic compound and the like can be used.

(solvent)
The solvent is not particularly limited, but any solvent that does not contain a functional group capable of reacting with the above components can be preferably used. Preferred solvents include aromatic solvents such as toluene and xylene, ester solvents such as ethyl acetate, butel acetate, methoxybutyl acetate and methoxypropyl acetate, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, and diethyl. Examples thereof include ether solvents such as ether, dibutyl ether, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, and diethylene glycol ethyl methyl ether. The type of organic solvent used is determined in consideration of the solubility of the obtained resin and the polymerization temperature, but the boiling point of methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, etc. is 120 ° C. or less from the viewpoint of resistance to residual solvent remaining during drying. Organic solvent is preferred. These may be used alone or in combination of two or more. The content of the solvent in the coating composition is not particularly limited, but it is preferable to adjust the viscosity of the coating composition so as to be suitable for the coating method. Usually, 5 to 90% by mass, more preferably 10 to 85% by mass, still more preferably 20 to 80% by mass of the entire coating composition for a hard coat film.

In addition to the above, the coating composition for a hard coat film of the present invention includes a fluorescent whitening agent, an antistatic agent, a flame retardant, an antibacterial agent, an antifungal agent, and ultraviolet rays as long as the effects of the present invention are not impaired. Absorbents, light stabilizers, antioxidants, plasticizers, defoamers, mold release agents, cross-linking agents and the like can be added.

The coating composition for a hard coat film of the present invention comprises the above-mentioned component (A), component (B), particles, and, if necessary, an ionizing radiation-curable monomer, inorganic fine particles, and a leveling agent different from the component (A). , Photopolymerization initiator, photopolymerization initiator, solvent and the like can be added in any order. In the coating composition of the present invention, it is necessary to disperse the particles so as to have a predetermined particle size distribution. As such a dispersion method, a bead mill, a ball mill, a sand mill, an attritor, a roll mill, a jet mill, a homogenizer, a paint shaker, a kneader, an agitator, a Henschel mixer, a colloid mill and the like can be used. In order to disperse the particles, all the components can be mixed and then dispersed, but the dispersion in which the particles are dispersed and the diluted solution in which the components other than the components contained in the dispersion are mixed are separately prepared. Then, both may be mixed.

(2) Hard Coat Film Next, the hard coat film of the present invention will be described below. The hard coat film of the present invention can be obtained by applying the above-mentioned coating composition for hard coat to a support and curing it. Further, a hard coat film can be obtained by providing a hard coat layer made of a hard coat film on at least one surface of the transparent support.
As the transparent support, highly transparent glass, a resin base material, or the like can be used. Examples of the resin material constituting the resin base material include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene, polypropylene, polyethylene, diacetyl cellulose, triacetyl cellulose, acetyl cellulose butyrate, polyvinyl chloride, polyvinylidene chloride, and polyvinyl alcohol. , Ethylene-vinyl acetate copolymer, polystyrene, polycarbonate, polymethylpentene, polysulfone, polyether ether ketone, polyether sulfone, polyetherimide, polyimide, fluororesin, nylon, acrylic, cycloolefin, norbornene compound, cellophane, etc. Can be mentioned. Considering the mechanical strength and dimensional stability, among these, stretch processing, particularly biaxially stretched polyethylene terephthalate film is preferable.
The thickness of the transparent support is not particularly limited and is appropriately set according to the application. Generally, in the case of glass, 0.3 mm to 5 mm is preferable, and in the case of a resin base material, 25 μm to 500 μm, more preferably 50 to 300 μm.

The method of applying the coating composition for hard coating to the support (base material) is not particularly limited, and a known method is used. For example, gravure coating method, bar coating method, knife coating method, roll coating method, blade coating method, die coating method, spin coating method, flow coating method, dip coating method, spray coating method, screen printing method, brush coating, etc. Can be mentioned.

In order to improve the adhesion to the hard coat film (layer), unevenness can be formed on the surface of the support by sandblasting, solvent treatment, or the like. In addition, surface treatments such as corona discharge treatment, chromic acid treatment, flame treatment, hot air treatment, plasma treatment, ozone / ultraviolet irradiation treatment, and formation of an undercoat easy-contact layer can also be performed. Further, an adhesive layer may be provided on one side or both sides of the support before applying the coating composition for hard coating.

The coating composition is applied to the support surface-treated as necessary, dried as necessary, and then irradiated with ionizing radiation to cure the coating composition to form a hard coat film. To do. As a method of irradiating the ionization irradiation line, a method of irradiating ultraviolet rays in the wavelength range of 100 nm to 400 nm emitted from an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a metal halide lamp, or a scanning type or curtain type electron beam. A method of irradiating an electron beam in a wavelength region of 100 nm or less emitted from an accelerator can be used.

The hard coat film of the present invention is a hard coat film containing a resin component and particles.
As for the resin component, at least the difference between the (A) ionizing radiation curable oligomer or monomer and the SP value of the (B) (A) component is 1.0 (cal / cm ³ ) ^1/2 or more, 3.0 (cal / cal /). cm ³ ) It is formed from a resin component that is less than ^1/2 , and the average particle size of the particles is 5% to 30% of the average thickness of the hard coat film. Since each component in the hard coat film has already been described as a component in the coating composition, the composition and physical properties of the hard coat film will be particularly described below.
As described above, when the coating composition containing the component (A), the component (B) and the particles is cured, the particles are formed along the waviness of the film surface formed by the phase separation of the components (A) and (B). A hard coat film is formed which is arranged and has an uneven shape on the surface. Here, the average particle size of the particles is 5% to 30% of the average thickness of the hard coat film. The average particle size of the particles is preferably 8% to 25%, more preferably 10% to 25% of the average thickness of the hard coat film.
The average particle size of the particles is the average particle size of the particles involved in the formation of surface irregularities, and is a value calculated by excluding fine particles having a particle size of less than 0.1 μm. Specifically, a hard coat film is photographed with an optical microscope at a magnification of 1000 times, and the particle size of 30 arbitrary particles excluding fine particles of less than 0.1 μm per 1 cm × 1 cm area is obtained. The average value of 28 particles excluding the maximum value and the minimum value was used as the average particle size of the particles.
The average particle size of the particles measured by the above method is preferably 0.3 μm to 1.8 μm, more preferably 0.6 μm to 1.3 μm. By setting the average particle size of the particles within the above range, even better anti-glare properties (prevention of glare) can be obtained, and even when installed in a high-definition color display, the effect of sufficiently preventing the glare phenomenon is sufficient. Can be obtained and transparency can be maintained.
The standard deviation of the particle size of the particles is preferably 0.3 μm to 1.5 μm, more preferably 0.5 μm to 1.0 μm. Further, the coefficient of variation of the particle size of the particles, that is, the standard deviation of the particle size of the particles / the average particle size of the particles (arithmetic mean value) is preferably 0.2 to 5, more preferably 0.4 to 2. , 0.3-1.5 are most preferable. By using particles having a standard deviation and a coefficient of variation in the above range, even better antiglare properties can be obtained, and even when installed in a high-definition color display, a sufficient effect of preventing glare can be obtained.
On the other hand, the average thickness of the hard coat film is the average value of the distance from the surface of the support coated with the hard coat film to the tip of the convex portion of the hard coat film. Specifically, a micrometer is used to measure the total thickness of the hard coat film. Then, it is calculated by reducing the thickness of the support (polyethylene terephthalate film) before forming the hard coat film measured in advance from the obtained value.
In the present invention, by setting the average particle size of the particles and the average thickness of the hard coat film as described above, particles having a small particle size are arranged on the film surface with respect to the hard coat film to form an uneven shape. Therefore, sufficient anti-glare properties can be exhibited even when used for a high-definition color display. Further, since the particles in the hard coat film can be made finer, the increase in haze is suppressed, and a highly transparent film can be obtained. Further, in the hard coat film of the present invention, the film thickness can be made sufficiently thicker than the particle size of the particles, so that a film having high hardness and excellent scratch resistance can be obtained. The average particle size of the particles of the present invention is preferably 8% to 25%, more preferably 10% to 25% of the average thickness of the hard coat film.

The average thickness of the hard coat film of the present invention is preferably 0.5 μm to 10 μm. By setting the average thickness of the hard coat film in this range, gloss can be suppressed and sufficient hardness and scratch resistance can be imparted, so that a more excellent hard coat film can be obtained.
Further, the pencil scratch value of the hard coat film or the hard coat film of the present invention in JIS K5600-5-4: 1999 is preferably H or more. By setting the pencil scratch value in this range, a hard coat film or a hard coat film having more excellent base material protection performance can be obtained.
The arithmetic mean roughness (Ra) according to JIS B0601 of the present invention is preferably 0.05 μm or more and less than 0.20 μm. By setting Ra of the hard coat film in this range, further excellent antiglare property and transparency can be obtained.

The 60-degree mirror glossiness of the hard-coated film or hard-coated film of the present invention in JIS Z8741 is preferably less than 130%, more preferably 120% or less, and further preferably 110% or less. Further, the haze of the hard coat film or the hard coat film of the present invention in JIS K7136 is preferably 30% or less, more preferably 20% or less, and further preferably 10% or less. By setting the glossiness and haze within the above ranges, a hard coat film or a hard coat film having even better performance can be obtained.
FIG. 1 shows an example of the relationship between the haze (cloudiness) and the 60-degree mirror surface gloss (gloss) of the conventional hard coat film and the hard coat film of the present invention. In general, when the glossiness of a hard coat film is lowered in order to suppress glare and enhance antiglare, the haze tends to increase and the transparency tends to decrease. Therefore, conventionally, when trying to obtain a hard coat film having a low haze and high transparency, the glossiness is high and the antiglare property (reflection prevention effect) is lowered. On the other hand, in the hard coat film of the present invention, even if the glossiness is lowered in order to suppress glare and enhance antiglare, the haze is maintained low, and excellent transparency and antiglare (anti-glare effect). ) Has become possible.
From FIG. 1, in the conventional hard coat film, when the glossiness is 90%, the haze is 11% and the transparency is lowered, whereas in the hard coat film of the present invention, even if the glossiness is 90%, It can be seen that the haze is as low as 6% and the transparency is high.
In the present invention, even if the haze of the hard coat film is 3%, a 60-degree mirror glossiness of 120% or less can be obtained. Further, when the haze is 7%, a 60-degree mirror gloss of 80% or less is obtained, when the haze is 10%, a 60-degree mirror gloss of 60% or less is obtained, and when the haze is 20%, 40% is obtained. The following 60-degree mirror glossiness was obtained.

As described above, a hard coat film can be obtained by providing a hard coat layer made of the hard coat film of the present invention on at least one surface of the transparent support. The haze of this hard coat film in JIS K7136 is preferably 30% or less.
Here, the hard coat film of the present invention may be provided on one surface of the transparent support, and another functional layer may be provided on the other surface. Further, the hard coat film of the present invention may be provided on one or both surfaces of the transparent support, and the functional layer may be provided on the hard coat layer. Functional layers include hard coat layer, anti-blocking layer, anti-Newton layer, antistatic layer, adhesive layer, printing layer, conductive layer, UV protection layer, heat shield layer, ink receiving layer, easy adhesive layer, metal vapor deposition layer, And so on.

The hard coat film of the present invention can be used for a touch panel. FIG. 2 is a schematic cross-sectional view showing an example of a touch panel. The touch panel 10 is a resistance film type touch panel 10 in which the conductive films 1a and 1b of a pair of panel plates 2a and 2b having the conductive films 1a and 1b are arranged via a spacer 3 so as to face each other. .. The hard coat film 4 of the present invention is laminated on the surface of the panel plate 2a which is the upper electrode of the panel plate. In FIG. 2, the hard coat film 4 is laminated on the transparent plastic film (base material) 5 of the upper panel plate 2a, and the cured product layer 6 is interposed under the transparent plastic film (base material) 5. The conductive film 1a is laminated. On the other hand, in the lower panel plate 2b, the conductive film 1b is laminated on the glass substrate 7.
Further, in the resistance film type touch panel 10 in which the conductive films 1a and 1b of the pair of panel plates having the conductive films 1a and 1b are arranged via the spacer 3 so as to face each other, the upper electrode of the panel plates The hard coat films 4 and 5 of the present invention can also be used for the panel plate 2a.
Further, in the capacitive touch panel having a conductive film on at least one side of the transparent substrate, the hard coat film of the present invention may be provided on the surface of the transparent substrate. Further, in a capacitance type touch panel having a conductive film on at least one side of the transparent substrate, the transparent hard coat film of the present invention can be used as the transparent substrate.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In the examples, unless otherwise specified, "%" or "part" indicates mass% or parts by mass.

(Example 1)
A polyethylene terephthalate film having a thickness of 188 μm (Cosmo Shine A4300, manufactured by Toyobo Co., Ltd.) was used as a support, and a coating composition for hard coating having the following composition was applied to one surface of the film using a baker type applicator. After drying this coating film, it was irradiated with ultraviolet rays with a high-pressure mercury lamp to obtain a hard coat film and a hard coat film having a thickness of 5 μm. The silica particles were circulated and dispersed by a disperser (bead mill disperser: manufactured by Inoue Seisakusho Co., Ltd.) using glass beads having a diameter of 1 mm at a flow velocity of 10 l / min until a predetermined particle size was reached. As a result of measuring the obtained coating composition using a laser diffraction type particle size distribution measuring device described later, the particle size of the silica particles was D50 = 0.8 μm, D90 = 3.0 μm, D90-D50 = 2.2 μm. Met.

<Composition of coating composition of Example 1>
・ A component A1 (light acrylate DPE-6: manufactured by Kyoeisha Chemical Co., Ltd.)
Mass% with respect to total resin solid content: 87%
・ B component B1 (Eslek KS1: manufactured by Sekisui Chemical Co., Ltd.)
Mass% of total resin solids: 3%
-Particle silica (Fine Seal X80: manufactured by Tokuyama Corporation)
Mass% to total solid content: 3.5%, manufacturer's catalog value: average particle size 2.4 μm)
-Ionizing radiation curable monomer (light acrylate PE-3A: manufactured by Kyoeisha Chemical Co., Ltd.)
Mass% with respect to total resin solid content: 10%
-Photopolymerization initiator (Irgacure 2959: manufactured by BASF Japan Ltd.)
Melting point 87 ° C to 92 ° C, 3% by mass with respect to the total solid content of component (A) and ionizing radiation curable monomer
・ Solvent Propylene glycol monomethyl ether (diluted to a solid content of 40% by mass)
・ Leveling agent (BYK331: manufactured by Big Chemie Japan)
(0.1% by mass in the coating composition)

(Measurement of particle size distribution of particles in coating composition)
The particle size distribution of the particles in the coating composition was measured using a HELOS laser diffraction type particle size distribution measuring device (manufactured by Symboltec), and the values of D50 and D90 were obtained.

(Example 2)
As shown in Table 1, a coating composition was prepared in the same manner as in Example 1 except that B1 was used as the B component and the following B2 was used, and then coated to obtain a hard coat film and a hard coat film. It was.
B2 (NK ester A9300-1CL: manufactured by Shin-Nakamura Chemical Industry Co., Ltd.)

(Example 3)
As shown in Table 1, a coating composition was prepared in the same manner as in Example 1 except that A1 was used as the component A and the following A2 was used, and then coated to obtain a hard coat film and a hard coat film. It was.
A2 (Art Resin UN904: manufactured by Negami Kogyo Co., Ltd.)

(Comparative Example 1)
As shown in Table 1, a coating composition was prepared in the same manner as in Example 1 except that B1 was used as the B component and the following B'was used, and then a coating film was applied to obtain a hard coat film and a hard coat film. Obtained.
B'(Eslek BL-S: manufactured by Sekisui Chemical Co., Ltd.)

(Comparative Example 2)
As shown in Table 1, a coating composition was prepared in the same manner as in Example 1 except that B "was used as the B component and the following B" was used, and then a coating film was applied to obtain a hard coat film and a hard coat film. Obtained.
The SP value of the resin was prepared by introducing a polar functional group into the B "polyvinyl alcohol resin. The SP value of the obtained polyvinyl alcohol resin was 14.0 (cal / cm ³ ) ^1/2 . ..

(Comparative Example 3)
As shown in Table 1, a coating composition was prepared in the same manner as in Example 1 except that no particles were added, and then coated to obtain a hard coat film and a hard coat film.

(Comparative Examples 4 to 7)
A coating composition was prepared in the same manner as in Example 1 except that the dispersion time of the silica particles was changed, and then coated to obtain a hard coat film and a hard coat film. Table 1 shows the results of measuring the particle size distribution of silica in each coating composition using the above-mentioned laser diffraction type particle size distribution measuring device.

(Evaluation)
Arithmetic mean roughness (Ra), pencil hardness, scratch resistance, glossiness, haze, total light transmittance, and high definition of the hard coat film or hard coat film of Examples 1 to 3 and Comparative Examples 1 to 7. Table 1 shows the results of measuring or evaluating the glare prevention (suppression) effect and antiglare property of the color display. In addition, each measurement or evaluation was performed as follows.

(Measurement of Arithmetic Mean Roughness (Ra))
Arithmetic mean roughness (Ra) was measured using a surface roughness meter (surfcom 480B: manufactured by Tokyo Seimitsu Co., Ltd.) by a method according to JIS B0601.
(Pencil hardness measurement)
Pencil hardness was measured by a method according to JIS K5600-5-4: 1999.
(Scratch resistance evaluation)
After wrapping # 0000 steel wool on a 3 cm ² cylindrical jig, placing it on the hard coat film of Examples and Comparative Examples, and reciprocating 100 times at a speed of 200 mm / sec with a load of 500 g. The state of the hard coat film was visually observed. As a result of visual evaluation, it was evaluated as ◯ when there were no scratches, Δ when there were less than 10 scratches, and × when there were 10 or more scratches.
(Gloss measurement)
The 60-degree mirror gloss was measured using a gloss meter (VG 7000: manufactured by Nippon Denshoku Kogyo Co., Ltd.) in accordance with JIS Z8741. The measurement light was incident from the hard coat film side.
(Transparency evaluation)
The transparency of the hard coat film was evaluated by measuring the haze (HAZE) and total light transmittance of the hard coat film. The haze was measured according to JIS K7136, and the total light transmittance was measured according to JIS K7361 using a haze meter (NDH 4000: manufactured by Nippon Denshoku Kogyo Co., Ltd.). The measurement light was incident from the hard coat film side.
(Evaluation of glare prevention effect and anti-glare property of high-definition color display)
When a hard coat film was laminated on a liquid crystal screen displaying a high-definition color image, it was visually evaluated whether or not the display screen became difficult to see due to reflection of external light or a glare phenomenon. As a result of visual evaluation, those that could prevent glare were rated as ◯, and those that could not be rated as x. Regarding the effect of preventing the glare phenomenon, when the display screen was not difficult to see, it was evaluated as ○, and when it became difficult to see, it was evaluated as ×.

As shown in Table 1, the hard coat film and the hard coat film of Comparative Example 1 had good scratch resistance, transparency, and an effect of preventing the glare phenomenon of the high-definition color display, but had a glossiness of 130. %, And sufficient anti-glare properties for high-definition color displays could not be obtained. In the hard coat film and the hard coat film of Comparative Example 1, the difference between the SP value (SP1) of the component (A) and the SP value of the component (B) was as small as 0.1 (cal / cm ³ ) ^1/2 . The affinity between the component (A) and the component (B) is high. For this reason, swells due to phase separation were not sufficiently formed, and it was not possible to have a structure in which particles were arranged along the swells on the film surface. Therefore, Ra was as small as 0.04 μm and the surface was flat, so that sufficient antiglare was obtained. It is probable that sex was not obtained. As a result of observing with an optical microscope, it was confirmed that in the hard coat film of Comparative Example 1, the particles were not arranged on the film surface but were buried in the film.
On the other hand, in the hard coat film and the hard coat film of Comparative Example 2, the scratch resistance and the antiglare property of the high-definition color display were good, but the haze was relatively high and the total light transmittance was low. Therefore, the transparency was low, and the effect of preventing glare on a high-definition color display could not be obtained. This is because in Comparative Example 2, the difference in SP value between the component (A) and the component (B) is as high as 3.3 (cal / cm ³ ) ^1/2, and the affinity between the two is low, so that the film is separated by phase separation. It is considered that this is because the surface becomes rough and the surface roughness is as high as 0.21 μm. As described above, a hard coat film having a rough surface cannot cope with a high-definition color display.

On the other hand, it was found that the hard coat films and the hard coat films of Examples 1 to 3 were excellent in scratch resistance, transparency, an effect of preventing the glare phenomenon of the high-definition color display, and antiglare. In Examples 1, 2 and 3, the difference between the SP values of the component (A) and the component (B) is 2.4 (cal / cm ³ ) ^1/2 and 1.0 (cal / cm ³ ) ^{1/2, respectively.} And 1.7 (cal / cm ³ ) ^1/2, it is considered that waviness was generated by appropriate phase separation, unevenness was formed on the film surface, and particles were arranged along the waviness on the film surface. As a result of observation with an optical microscope, it was confirmed that particles were arranged along the waviness on the surface of the hard coat film of Examples 1, 2 and 3. The Ras of the hard coat film and the hard coat film of Examples 1, 2 and 3 are 0.09 μm, 0.10 μm and 0.09 μm, respectively, and the film structure forms appropriate irregularities on the film surface. It is considered that a better effect was obtained.

In Comparative Example 3, the same components (A) and (B) as in Example 1 are used, but no particles are added. Therefore, even if undulations occur due to appropriate phase separation and irregularities are formed on the film surface, Ra is as small as 0.03 μm and the film surface is smooth, so the glossiness is as high as 150% and the color is high-definition. It is probable that the anti-glare property for the display was not obtained. From this, the effect of adding particles of the present invention was confirmed.
In Comparative Example 4, the composition was the same as that of Example 1, but the dispersion time was lengthened so that the D50 of the silica particles was 0.3 μm. Therefore, Ra of the hard coat film is 0.04 μm, which is smaller than that of Example 1, and although it is improved as compared with Comparative Example 3 to which no particles are added, the glossiness is 108% and the definition is high. No anti-glare property was obtained for the color display.
Comparative Example 5 also had the same composition as that of Example 1, but was prepared so that the D50 of the silica particles was 1.8 μm by shortening the dispersion time. In Comparative Example 5, there were no problems with scratch resistance, transparency, and anti-glare property for a high-definition display, but no glare prevention effect was obtained.
Comparative Example 6 and Comparative Example 7 also had the same composition as that of Example 1, but were prepared so that D90-D50 became 0.3 μm and 4.3 μm, respectively, by changing the dispersion conditions. As shown in Table 1, it was confirmed that the glare of the high-definition display could not be prevented in any of Comparative Examples 6 and 7. From this, it was confirmed that the effect of preventing glare cannot be obtained regardless of whether the particle size variation of the particles in the coating composition is small or large, and it is necessary to prepare the particle size to a predetermined variation as in the present invention. It was.

( Reference Examples 4 to 5, Examples 6 to 8)
A hard coat film containing particles having different average particle diameters was prepared by keeping the average film thickness of the hard coat film constant at 6 μm and changing the particle size and dispersion conditions of the silica particles to be added. The other composition and production method were the same as in Example 1. As a result of measuring the average particle size of the particles in each hard coat film by the above-mentioned method, 0.3 μm ( Reference Example 4), 0.42 μm ( Reference Example 5), 0.6 μm (Example 6), 1. It was 3 μm (Example 7) and 1.8 μm (Example 8) (see Table 2). Table 2 shows the results of calculating the average particle size of the obtained hard coat film and the value of (average particle size / average thickness of hard coat film) × 100. In addition, the pencil hardness, scratch resistance, glossiness, haze, total light transmittance of each hard coat film or hard coat film, and the anti-glare effect and anti-glare property of the high-definition color display are measured or evaluated. The results are also shown in Table 2.

(Comparative Examples 8 and 9)
The average film thickness of the hard coat film was kept constant at 6 μm, and the particle size and dispersion conditions of the silica particles to be added were changed so that the average particle size was 0.18 μm (Comparative Example 8) and 2.1 μm (Comparative Example 9). A hard coat film containing particles was prepared. The other composition and production method were the same as in Example 1. Table 2 shows the results of calculating the average particle size of the obtained hard coat film and the value of (average particle size / average thickness of hard coat film) × 100. In addition, the pencil hardness, scratch resistance, glossiness, haze, total light transmittance of each hard coat film or hard coat film, and the anti-glare effect and anti-glare property of the high-definition color display are measured or evaluated. The results are also shown in Table 2.

In Comparative Example 8 in which the value of (average particle size / average thickness of hard coat film) × 100 was 3, the scratch resistance, transparency, and anti-glare effect corresponding to high definition were good, but the gloss was 120%. It was found that the anti-glare property corresponding to high definition could not be obtained. On the other hand, the values of (average particle size / average thickness of hard coat film) × 100 are sufficient in Reference Examples 4, 5, and Examples 6, 7 and 8 of 5, 7, 10, 22, and 30. It was found that scratch resistance, transparency, anti-glare effect for high definition and anti-glare properties can be obtained. On the other hand, in Comparative Example 9 in which the value of (average particle size / average thickness of hard coat film) × 100 was 35, scratch resistance, transparency, and antiglare property corresponding to high definition were good, but glare prevention. No effect was obtained. As a result of the above, when the value of (average particle size / average thickness of hard coat film) × 100 is in the range of 5 to 30, the color display has high hardness, excellent antiglare and transparency, and high definition. It was found that a hard coat film that can prevent the glare phenomenon can be obtained even when used for the purpose. In particular, it was confirmed that more excellent effects were obtained in Examples 6 and 7 in which the value of (average particle size / average thickness of hard coat film) × 100 was set to 10 and 22.

(Examples 9 and 10)
A hard coat film and a hard coat film having different average thicknesses were prepared using the hard coat film-like coating composition prepared in the same manner as in Example 1 except that the dispersion conditions of the silica particles were changed. The average particle size of the silica particles in the obtained hard coat film was 0.8 μm. The film thicknesses of Examples 9 and 10 were 5.3 μm and 2.7 μm, respectively, and the value of (average particle size / average thickness of hard coat film) × 100 was 15 and 30. Measure the pencil hardness, scratch resistance, glossiness, haze, total light transmittance, and anti-glare effect and anti-glare property of the high-definition color display of the hard coat film or hard coat film of Examples 9 and 10. Alternatively, the evaluation results are shown in Table 3.

(Comparative Examples 10 and 11)
Using the coating composition for a hard coat film prepared in the same manner as in Examples 9 and 10, hard coat films having an average thickness of 27 μm (Comparative Example 10) and 1 μm (Comparative Example 11) were prepared. Measure the pencil hardness, scratch resistance, glossiness, haze, total light transmittance, and anti-glare effect and anti-glare property of the high-definition color display of the hard coat film or hard coat film of Comparative Examples 10 and 11. Alternatively, the evaluation results are also shown in Table 3.

In Comparative Example 10 in which the value of (average particle size / average thickness of hard coat film) × 100 was 3, the scratch resistance, transparency, and anti-glare effect corresponding to high definition were good, but the gloss was 140%. It was found that the anti-glare property corresponding to high definition could not be obtained. On the other hand, in Examples 9 and 10 in which the value of (average particle size / average thickness of hard coat film) × 100 is 15 and 30, sufficient scratch resistance, transparency, and glare prevention corresponding to high definition are achieved. It was found that the effect and anti-glare property were obtained. On the other hand, in Comparative Example 11 in which the value of (average particle size / average thickness of hard coat film) × 100 was 80, sufficient scratch resistance could not be obtained. From this, even when the film thickness of the hard coat film is changed, the value of (average particle size / average thickness of the hard coat film) × 100 is high hardness, antiglare and transparent in the range of 5 to 30. It was found that a hard coat film with excellent properties and capable of preventing glare even when used for a high-definition color display can be obtained.

(Example 11)
A hard coat film and a hard coat film were prepared using the hard coat film-like coating composition prepared in the same manner as in Example 1 except that the amount of silica particles added was changed. The content of the 11 particles of Example 11 was 2.9% by mass with respect to the total mass of the hard coat film. The average particle size of the silica particles in the hard coat film was 0.8 μm, and the value of (average particle size / average thickness of the hard coat film) × 100 was 16. The results of measuring or evaluating the pencil hardness, scratch resistance, glossiness, haze, total light transmittance, and the glare prevention effect and antiglare property of the high-definition color display of the hard coat film of Example 11 are shown. Shown in 4. The results of Example 1 and Comparative Example 1 are also shown for comparison.

In Example 11 in which the content of particles was reduced as compared with Example 1, the haze was lowered while maintaining scratch resistance, an effect of preventing glare phenomenon when used for a high-definition color display, and antiglare. I understand. On the other hand, as the haze decreased, the glossiness increased, but sufficient anti-glare properties were obtained. Here, when Example 11 and Comparative Example 1 were compared, the haze was 4.5%, while the glossiness was 97% and 130%, respectively. From this, it was confirmed that in the present invention, a hard coat film having excellent antiglare properties can be realized while maintaining transparency.

The hard coat film and hard coat film of the present invention can be used not only as a surface base material for various display devices such as liquid crystal display devices, CRT display devices, plasma display devices, and EL display devices, but also as electrode sensor films, touch panel films, and the like. Can also be used as.

1a, 1b ... Conductive film 2a, 2b ... Panel plate 3 ... Spacer 4 ... Hard coat film 5 ... Transparent plastic film (base material)
6 ... Hardened material layer 7 ... Glass substrate 10 ... Touch panel

Claims (9)

A hard coat film containing a resin component and particles.
The difference between the SP value of the (A) ionizing radiation curable oligomer or monomer and the (B) (A) component of the resin component is 1.0 (cal / cm ³ ) ^1/2 or more, and 3.0 (cal). / Cm ³ ) Formed from resin components that are less than ^1/2 ,
The average particle size of the particles is 0.6 μm to 1.3 μm.
The average particle diameter of the particles, Ri 5% to 22% der of the average thickness of the hard coat layer,
A hard coat film, wherein the component (A) is a (meth) acrylate oligomer or a monomer . The hard coat film according to claim 1, wherein the average thickness of the hard coat film is 2.7 μm to 10 μm. The hard coat film according to claim 1 or 2, wherein the particles have a refractive index difference from the resin component of 0.03 to 0.10. The hard coat film further contains inorganic fine particles having an average particle diameter of 5 nm to 50 nm of the primary particles, and the inorganic fine particles have a refractive index difference of 0.03 or more from the resin component, according to claims 1 to 3. The hard coat film according to any one of the above items. The hard coat film according to any one of claims 1 to 4, wherein the content of the particles is 1% by mass to 10% by mass with respect to the total mass of the hard coat film. The hard coat film according to claim 4, wherein the content of the inorganic fine particles is 1% by mass to 12% by mass with respect to the total mass of the hard coat film. The hard coat film according to any one of claims 1 to 6, wherein the arithmetic mean roughness (Ra) according to JIS B0601 is 0.05 μm or more and less than 0.20 μm. A hard coat film comprising a hard coat layer made of the hard coat film according to any one of claims 1 to 7 on at least one surface of the transparent support. A touch panel comprising the hard coat film according to any one of claims 1 to 7.