KR101496456B1 - Hard coat film - Google Patents

Abstract

An object of the present invention is to provide a hard coating film having a surface hardness that is sufficient and sufficient as a surface protective film for various image display devices and which has less bending due to curing shrinkage. (A) an active energy ray-curable compound having three or more ethylenically unsaturated groups in a molecule and having an isocyanurate derivative other than the isocyanurate derivative, and (B) Is a hard coating film having a hard coating layer formed of an active energy ray cured resin layer formed using a hard coating layer forming material containing an unsaturated group and containing 150 to 550 parts by mass of an active energy ray curable isocyanurate derivative .

Description

Hard Coat Film {HARD COAT FILM}

TECHNICAL FIELD The present invention relates to a hard coating film, and more particularly, to a hard coating film having a necessary and sufficient surface hardness as a surface protective film of various image display devices, and having a small curl due to curing shrinkage.

Conventionally, a hard coating film has been widely used in various image display devices such as LCD (liquid crystal display), touch panel, CRT (cathode ray tube), PDP (plasma display panel), EL (electroluminescence) And is used for the purpose of preventing reflection and reflection. Further, the LCD is used to protect the polarizer. The hard coating film generally has a hard coating layer formed on the base film by thermal curing, activation energy ray curing or the like.

On the other hand, in recent years, the image display device has been required to be thin. In this case, it is required to use a base film having a thickness of about half the conventional thickness (about 80 to 125 占 퐉) for the hard coating film. However, if a conventional hard coating layer is formed on such a thin substrate film, curling occurs in the hard coating film due to curing shrinkage of the hard coating layer, resulting in difficulty in use as a surface protective film , Resulting in an undesirable condition.

Thus, in order to suppress the occurrence of curling by suppressing the curing shrinkage, a curable composition containing a compound having at least three ethylenic unsaturated groups and at least one isocyanurate ring in the same molecule is applied on a substrate to form a cured Treated hard coat layer having a thickness of not less than 15 占 퐉 and not more than 200 占 퐉 (see, for example, Patent Document 1). However, in this case, there is a problem that the thickness of the hard coat layer must be set to be large in order to obtain sufficient hardness.

Also disclosed is a technique of hardening an isocyanurate derivative having two ethylenically unsaturated groups and a composition containing pentaerythritol acrylate into a hard coat layer (see, for example, Patent Document 2). However, in this technique, since the hardness of the cured product of the isocyanurate derivative is insufficient, the hardness of the hard coat layer obtained by curing the composition is further improved.

[Prior Art Literature]
[Patent Document 1]

Japanese Patent Application Laid-Open No. 2004-141732

[Patent Document 2]

Japanese Patent Application Laid-Open No. 2005-103973

The object of the present invention is to provide a hard coating film which has sufficient surface hardness as a surface protective film of various image display devices and has less bending due to curing shrinkage under such circumstances.

DISCLOSURE OF THE INVENTION As a result of intensive studies to develop a hard coating film having the above-described preferable properties, the present inventors have found that an active energy ray-curable compound and an active energy ray-curable isocyanurate derivative, each having a specific structure, It has been found that the object can be achieved by forming a hard coating layer composed of an active energy ray hardened resin layer on a base film by using a hard coating layer forming material contained in the hard coating layer forming material and completing the present invention based on this knowledge .

That is,

(1) A positive active energy ray-curable compound having three or more ethylenically unsaturated groups in a molecule and having an active energy ray-curable compound other than an isocyanurate derivative, and (B) Or more of an active energy ray-curable isocyanurate derivative having an ethylenic unsaturated group and having an ethylenic unsaturated group, and 150 to 550 parts by mass of an active energy ray- film,

[2] The hard coating film according to the above [1], wherein the component (B) isocyanurate has a structure in which an ethylenic unsaturated group is bonded to all three nitrogen atoms of the isocyanuric acid skeleton,

[3] A method for manufacturing a hard-coated film, comprising the steps of: (1) forming a hard coating film on a flat plate by cutting a 10-cm square, wherein a total of curl heights at four corners are 100 mm or less, ] Or the hard coating film described in [2]

[4] The hard coating film according to any one of [1] to [3], wherein the base film is a triacetyl cellulose film having a thickness of 80 μm or less,

[5] The hard coating film according to any one of [1] to [4], wherein the thickness of the hard coating layer is 3 to 10 μm,

.

According to the present invention, it is possible to provide a hard coating film having a surface hardness that is sufficient and sufficient as a surface protective film of various image display devices, and which has less bending due to curing shrinkage.

The hard coat film of the present invention can be produced by forming a hard coat layer forming material containing an active energy ray curable compound (A) other than an isocyanurate derivative and (B) an active energy ray curable isocyanurate derivative on a base film And a hard coating layer composed of an active energy ray curable resin layer formed.

There is no particular limitation on the base film used in the hard coating film of the present invention, and it can be suitably selected from plastic films known as base materials for conventional optical hard coating films. Examples of such plastic films include polyester films such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate, polyethylene films, polypropylene films, cellophane, diacetylcellulose films, triacetylcellulose films, acetylcellulose Polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyetheretherketone film, A polyimide film, a fluororesin film, a polyamide film, an acrylic resin film, a norbornene resin film, a cycloolefin resin film, and the like.

These base films may be either transparent or translucent, and may be colored or non-colored, and may be appropriately selected depending on the application. For example, when used as a polarizer protective film for a liquid crystal display, a colorless transparent triacetylcellulose film is very suitable.

The thickness of these base films is not particularly limited and may be suitably selected in accordance with the circumstances, but is preferably 80 占 퐉 or less, and more preferably 20 to 80 占 퐉, from the viewpoint of effectively suppressing curling. The base film may be subjected to surface treatment on one side or both sides by an oxidation method, an irregularity method or the like, if desired, for the purpose of improving the adhesion with the layer formed on the surface of the base film. Examples of the oxidation method include a corona discharge treatment, a plasma treatment, a chromic acid treatment (wet type), a flame treatment, a hot air treatment, an ozone / ultraviolet ray irradiation treatment and the like. Examples of the irregularity include sandblasting, And a solvent treatment method. These surface treatment methods are appropriately selected depending on the kind of the base film, but generally, the corona discharge treatment method is preferably used in view of effects and operability.

In the hard coat film of the present invention, the hard coat layer to be laminated on the base film may be formed by a combination of (A) an active energy ray-curable compound having three or more ethylenic unsaturated groups in the molecule, B) an active energy ray-curable isocyanurate derivative having at least three ethylenically unsaturated groups in the molecule.

The active energy ray curable compound in the component (A) means a compound having energy both in an electromagnetic wave or in a charged particle beam, that is, a compound capable of crosslinking or curing by irradiation with ultraviolet rays or electron beams. Of course, component (B) is also one kind of active energy ray-curable compound.

The active energy ray-curable compound (A) has three or more ethylenic unsaturated groups in the molecule and is a compound other than an isocyanurate derivative. Examples of such compounds include trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol (meth) acrylate, propylene oxide modified trimethylolpropane tri (Meth) acrylate and hexa (meth) acrylate. These may be used singly or in combination of two or more. The number of the ethylenic unsaturated groups is not particularly limited as long as it is 3 or more, but 3 to 6 is preferable from the viewpoint of curl suppression.

On the other hand, as the active energy ray-curable isocyanurate derivative having three or more ethylenically unsaturated groups in the molecule as the component (B), any compound having a structure in which three or more ethylenic unsaturated groups are bonded to the isocyanuric acid skeleton, There is no particular limitation, but from the viewpoints of performance and ease of production, it is preferable that all of the three nitrogen atoms of the isocyanuric acid skeleton have a structure in which an ethylenic unsaturated group is bonded. As the ethylenic unsaturated group, a (meth) acryloyloxy group is preferable. Examples of such an isocyanurate derivative include compounds represented by the general formula (I)

However,

(Wherein A ¹ to A ³ each independently represent a (meth) acryloyloxy group, and R ¹ to R ³ each independently represent an alkylene group having 2 to 4 carbon atoms)

And tris [(meth) acryloyloxyalkyl] isocyanurate represented by the following formula

In the general formula (I), the alkylene group represented by R ¹ to R ³ may be any of a linear chain and a branched chain. Specific examples thereof include an ethylene group, a propylene group, a trimethylene group, Can be mentioned. The (meth) acryloyloxyalkyl groups bonded by three nitrogen atoms may be the same or different.

Examples of the tris [(meth) acryloyloxyalkyl] isocyanurate represented by the above general formula (I) include tris (2-acryloyloxyethyl) isocyanurate, tris (2-methacryloyloxyethyl) isocyanurate, tris (3-methacryloyloxypropyl) isocyanurate, and the like.

In the present invention, as the component (B), one of these compounds may be used alone, or two or more of these compounds may be used in combination. The content of the component (B) in the hard coat layer forming material is selected in the range of 150 to 550 parts by mass with respect to 100 parts by mass of the component (A). When the content is less than 150 parts by mass, the curl suppressing effect of the obtained hard coat film is not sufficiently exhibited. When the content exceeds 550 parts by mass, the hardness of the hard coat film is lowered. The content of component (B) is preferably in the range of 180 to 520 parts by mass from the viewpoint of balance of curl generation inhibiting effect and surface hardness.

In addition to the components (A) and (B) described above, the hard coat layer forming material may contain other active energy ray-curable compounds, if necessary, insofar as the object of the present invention is not impaired.

Examples of other active energy ray curable compounds include active energy linear polymerizable prepolymers and / or active energy ray polymerizable monofunctional monomers and bifunctional monomers.

Examples of the active energy linear polymerizable prepolymer include polyester acrylate, epoxy acrylate, urethane acrylate, and polyol acrylate.

Examples of the active energy ray-polymerizable monofunctional monomer include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (Meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isobornyl (meth) acrylate and the like can be appropriately selected and used.

Examples of the active energy linear polymerizable bifunctional monomer include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) (Meth) acrylates such as polyethylene glycol di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl (Meth) acryloyloxyethyl] isocyanurate, bis [2- (meth) acryloxyethyl] 2-hydroxy Ethyl isocyanurate, and the like can be appropriately selected and used.

The hard coating layer forming material may contain a photopolymerization initiator. Examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, 4- (2-hydroxyethoxy) phenyl- Ethyl anthraquinone, 2-tert-butylanthraquinone, 2-tert-butylanthraquinone, 2-ethylhexanoic acid, -Aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethylketal, Phenon dimethyl ketal, p-dimethylamine benzoate Terre et al. These may be used alone or in combination of two or more. The compounding amount thereof is usually selected in the range of 0.2 to 10 parts by mass based on 100 parts by mass of the active energy ray-curable compound.

The hard coating layer forming material may contain a solvent. Examples of the solvent include aliphatic hydrocarbons such as hexane and heptane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and ethylene chloride, alcohols such as methanol, ethanol, propanol and butanol, acetone, Ketones such as 2-pentanone, isophorone and cyclohexanone, esters such as ethyl acetate and butyl acetate, cellosolve solvents such as ethyl cellosolve, and glycol ether solvents such as propylene glycol monomethyl ether. have. These solvents may be used singly or as a mixture of two or more kinds thereof.

In addition, it is also possible to suitably contain various additives such as a filler for imparting anti-glare property, a reactive silicone compound, a photosensitizer, a polymerization inhibitor, a crosslinking agent, an antioxidant, a UV absorber, a light stabilizer, a leveling agent, .

As the filler imparting anti-glare properties, any of those conventionally known as fillers for imparting anti-glare properties can be suitably selected and used. Examples of such fillers include agglomerates of silica particles having an average particle diameter of about 1.5 to 7 占 퐉 and silica particles having an average diameter of about 0.5 to 10 占 퐉 or aggregates having an average particle diameter of about 0.5 to 5 占 퐉 Of silica particles and metal oxide fine particles having an average particle size of about 1 to 60 nm. The content of these fillers in the hard coat layer is preferably selected appropriately in consideration of antiglare performance and scratch resistance of the obtained hard coat film.

As the reactive silicone compound, a silicone compound having a radically polymerizable unsaturated group in the molecule can be used. The silicone compound is crosslinked and cured by irradiation with active energy rays, and has an action of imparting stain resistance and low friction to the hard coat layer.

In the present invention, a hard coating layer-forming material (coating liquid) containing each of the above-described components and adjusted to a concentration suitable for coating is prepared, and then a conventionally known method such as a bar coating method, A coating film is formed by a coating method such as a coating method, a roll coating method, a blade coating method, a die coating method and a gravure coating method so that the thickness after curing becomes a predetermined value, Deg.] C for about 1 to 3 minutes, and then the dry film is irradiated with an active energy ray to cure the coating film, whereby a hard coat layer is formed.

Examples of the active energy ray include ultraviolet rays and electron rays. The ultraviolet ray is obtained by a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, etc., and the irradiation amount is usually 100 to 50 O mJ / cm 2, while the electron beam is obtained by an electron beam accelerator or the like. Of these active energy rays, ultraviolet rays are particularly suitable. When an electron beam is used, a cured film can be obtained without adding a photopolymerization initiator.

The thickness of the hard coat layer is usually about 3 to 10 mu m. In the thus obtained hard coating film, the sum of the curl heights of the four corners generated when the hard coating film cut to 10 cm square is placed on the flat plate is 100 mm or less, and the pencil hardness is 2H or more to be. The method of measuring the curl height and pencil hardness will be described in detail later.

In the hard coat film of the present invention, a transparent conductive thin film layer having a thickness of about 10 to 45 nm can be formed on the hard coat layer, if necessary. There is no particular limitation on the method for forming the transparent conductive thin film layer, and conventionally known methods such as physical vapor deposition (PVD) method such as sputtering can be employed.

Examples of the material of the transparent conductive thin film include indium oxide, tin oxide, zinc oxide, indium-tin oxide, tin-antimony oxide, zinc-aluminum oxide and indium-zinc oxide.

The hard coating film of the present invention having a hard coating layer having a transparent conductive thin film layer formed on its surface has a high scratch resistance of the hard coating layer, It is possible to solve the problem that the transparent conductive thin film of the touch-side transparent plastic substrate is worn, cracked, or peeled off from the substrate.

In the present invention, an antireflection layer, for example, a siloxane coating film, a fluorine coating film, or the like can be formed on the surface of the hard coat layer for the purpose of imparting antireflection property, if necessary. In this case, the thickness of the antireflection layer is preferably about 0.05 to 0.2 mu m. The reflectance at a wavelength of 550 nm is preferably 3.5% or less. By forming the antireflection layer, the halation of the screen caused by reflection by sunlight, fluorescent lamp, etc. is eliminated and the reflectance of the surface is suppressed, whereby the total light transmittance is increased and the transparency is improved.

In the present invention, a pressure-sensitive adhesive layer for adhering to an adherend can be formed on the side opposite to the hard coat layer of the base film. As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, those for optical use, for example, acrylic pressure-sensitive adhesives, urethane pressure-sensitive adhesives and silicone pressure-sensitive adhesives are preferably used. The thickness of the pressure-sensitive adhesive layer is usually 5 to 100 占 퐉, preferably 10 to 60 占 퐉.

Further, a release sheet can be formed on the pressure-sensitive adhesive layer, if necessary. Examples of the peeling sheet include paper coated with a releasing agent such as a silicone resin, and various kinds of plastic films such as grainy paper, coated paper, and laminated paper. The thickness of the release sheet is not particularly limited, but is usually about 20 to 150 mu m.

 The hard coating film of the present invention has a surface hardness that is sufficient and sufficient as a surface protective film of various image display devices, and has less bending due to curing shrinkage.

<Examples>

EXAMPLES Next, the present invention will be described in more detail by examples, but the present invention is not limited by these examples.

The performance of the hard coat film obtained in each example was evaluated according to the following method.

(1) Pencil Hardness

Pencil scratching Using a pencil hardness tester [manufactured by TOYO SEIKI SEISAKU-SHO, Ltd., type "NP"], a pencil scratch resistance test was carried out in accordance with JIS K 5600-5-4 Respectively.

(2) Curl

The hard coating film was cut at a right angle of 10 cm to prepare a test piece. The test piece was allowed to stand for 24 hours under an environment of 23 ° C and 55% relative humidity (RH), and then the test piece was concaved on a horizontal glass plate And the extents of the four corners were measured according to a regular rule, and the total value was obtained.

Preparation Example 1 Preparation of Coating Solution A

(100 parts by mass) of (A) pentaerythritol triacrylate (product of Shin NAKANURA CHEMICAL CO., LTD., Trade name "NK Ester A-TMM-3", solid content concentration 100% , (B) Tris (2-acryloyloxyethyl) isocyanurate [trade name: ARONIX M-315, solid concentration 100%] manufactured by TOAGOSEI Kagaku Kogyo Co., And 6 parts by mass of 1-hydroxy-cyclohexyl phenyl ketone (trade name: Irgacure 184, manufactured by Ciba Specialty Chemicals, Inc.) as a photopolymerization initiator were added, and the solid content concentration Was adjusted to 40 mass% with propylene glycol monomethyl ether to prepare coating liquid A.

Preparation Example 2 Preparation of coating liquid B

Except that the amount of (B) tris (2-acryloyloxyethyl) isocyanurate was changed to 500 parts by mass and the amount of 1-hydroxy-cyclohexylphenylketone was changed to 12 parts by mass in Preparation Example 1 , And coating liquid B was prepared in the same manner as in Preparation Example 1.

Preparation Example 3 Preparation of coating liquid C

In the same manner as in Preparation Example 1 except that (A) pentaerythritol triacrylate was changed to pentaerythritol tetraacrylate (trade name: "NK Ester A-TMMT", manufactured by Shin-Nakamura Kagaku Kogyo Co., Ltd., solid concentration: 100% , A coating liquid C was prepared in the same manner as in Preparation Example 1.

Preparation Example 4 Preparation of Coating Solution D

(A) pentaerythritol triacrylate was changed to pentaerythritol tetraacrylate (trade name: "NK Ester A-TMMT", Shin-Nakamura Kagaku Kogyo Co., Ltd., solid concentration: 100%) , A coating liquid D was prepared in the same manner as in Preparation Example 2.

Preparation Example 5 Preparation of Coating Solution E

(A) pentaerythritol triacrylate was changed to dipentaerythritol hexaacrylate (trade name: Aronix M-400, solid content concentration: 100%) manufactured by Toagosei Chemical Industry Co., Ltd. , A coating liquid E was prepared in the same manner as in Preparation Example 1

Preparation Example 6 Preparation of Coating Solution F

(A) pentaerythritol triacrylate was changed to dipentaerythritol hexaacrylate (trade name: Aronix M-400, solid content concentration: 100%, manufactured by Toagosei Kaikako Kogyo Co., Ltd.) , A coating liquid F was prepared in the same manner as in Preparation Example 2.

Preparation Example 7 Preparation of Coating Solution G

A coating liquid G was prepared in the same manner as in Preparation Example 1 except that the amount of tris (2-acryloyloxyethyl) isocyanurate was changed to 350 parts by mass in Preparation Example 1.

Preparation Example 8 Preparation of Coating Solution H

Except that the amount of (B) tris (2-acryloyloxyethyl) isocyanurate was changed to 100 parts by mass and the amount of 1-hydroxy-cyclohexylphenylketone was changed to 5 parts by mass in Preparation Example 1 , And coating liquid H was prepared in the same manner as in Preparation Example 1.

Preparation Example 9 Preparation of Coating Solution I

In the same manner as in Preparation Example 8, except that (A) pentaerythritol triacrylate was replaced by dipentaerythritol hexaacrylate (trade name: Aronix M-400, solid content concentration: 100%, manufactured by Toagosei Kaikako Kogyo Co., The coating liquid I was prepared in the same manner as in Preparation Example 8, except that the coating liquid I was changed.

Preparation Example 1O Preparation of coating liquid J

Except that the amount of (B) tris (2-acryloyloxyethyl) isocyanurate was changed to 600 parts by mass and the amount of 1-hydroxy-cyclohexylphenylketone was changed to 14 parts by mass in Preparation Example 1 , And coating liquid J was prepared in the same manner as in Preparation Example 1.

Preparation Example 11 Preparation of coating liquid K

(A) pentaerythritol triacrylate was changed to dipentaerythritol hexaacrylate (trade name: Aronix M-400, solid content concentration: 100%, manufactured by Toagosei Kaikako Kogyo Co., Ltd.) , Coating liquid K was prepared in the same manner as in Preparation Example 10.

Example 1

Coating solutions A to G prepared in Preparation Examples 1 to 7 were coated on a triacetylcellulose film (Fujishahin Film Co., Ltd., trade name &quot; T40UZ &quot;) having a thickness of 40 탆 as a base film using a bar coater After drying at 70 캜 for one minute, ultraviolet rays were applied to the coated surface at a light quantity of 230 mJ / cm 2 and cured to prepare each hard coating film. The thickness of the hard coat layer was 3 mu m.

Table 1 shows the performance evaluation results of each hard coating film.

Example 2

Each hard coating film was prepared in the same manner as in Example 1 except that the coating was performed so that the thickness after drying in Example 1 was 6 占 퐉. The thickness of the hard coat layer was 6 mu m.

Table 1 shows the performance evaluation results of each hard coating film.

Example 3

Each hard coating film was prepared in the same manner as in Example 1, except that the coating was performed so that the thickness after drying in Example 1 was 10 占 퐉. The hard coating layer had a thickness of 10 mu m.

Table 1 shows the performance evaluation results of each hard coating film.

Comparative Example 1

The coating solutions H and I prepared in Preparation Examples 8 and 9 were applied onto a triacetyl cellulose film (Fujishahin Film Co., Ltd., trade name "T40UZ") having a thickness of 40 μm as a base film, 6 占 퐉, dried at 70 占 폚 for 1 minute, and cured by irradiating ultraviolet rays with a light quantity of 230 mJ / cm2 on a coated surface to prepare respective hard coating films.

Table 1 shows the performance evaluation results of each hard coating film.

Comparative Example 2

The coating liquids J and K prepared in Preparation Examples 10 and 11 were applied onto a triacetyl cellulose film (Fujishahin Film Co., Ltd., trade name "T40UZ") having a thickness of 40 μm as a base film, 6 占 퐉, dried at 70 占 폚 for 1 minute, irradiated with ultraviolet light at a light quantity of 230 mJ / cm2, and hardened to prepare hard coating films.

Table 1 shows the performance evaluation results of each hard coating film.

Coating liquid Curl (mm) Pencil hardness

Example 1
[Thickness of hard coat layer: 3 mu m]

A 18.0 2H B 6.0 2H C 11.5 2H D 7.0 2H E 16.5 2H F 10.0 2H G 10.0 2H

Example 2
[Thickness of hard coating layer: 6 mu m]

A 33.0 2H B 25.0 2H C 49.0 2H D 30.5 2H E 61.5 2H F 31.5 2H G 29.0 2H

Example 3
[Thickness of hard coat layer: 10 mu m]

A 88.5 2H B 42.5 2H C 92.0 2H D 58.0 2H E 96.0 3H F 64.5 2H G 65.0 2H Comparative Example 1
[Thickness of hard coating layer: 6 mu m] H 115 2H I Not measurable * 3H Comparative Example 2
[Thickness of hard coating layer: 6 mu m] J 21.0 H K 27.5 H

* Hard coating film was rounded, and measurement could not be made.

As can be seen from Table 1, the hard coating films (Examples 1 to 3) of the present invention all have a pencil hardness of 2H or more and a curl amount (total of four corners) is less than 100 mm.

On the contrary, in Comparative Example 1, the pencil hardness is high at 2H or more, but the curl amount is large and the glass is not acceptable. In Comparative Example 2, the curl amount is small, but the pencil hardness is H,

The hard-coating film of the present invention has a sufficient surface hardness as a surface protective film of various image display devices, has less bending due to curing shrinkage, and is used for a touch panel, a polarizing plate, a quarter- It is very suitably used as a cover film of an optical disk or a protective film of various displays.

Claims (7)

(A) an active energy ray-curable compound having three or more ethylenically unsaturated groups in the molecule and having an isocyanurate derivative other than the isocyanurate derivative, and (B) Having an ethylenic unsaturated group and having an ethylenic unsaturated group, and 150 to 550 parts by mass of an active energy ray-curable isocyanurate derivative having an ethylenic unsaturated group or more, Wherein the sum of the curl heights of the four corners generated when the hard coating film is placed on the flat plate is 100 mm or less. The method according to claim 1, Characterized in that the component (B) isocyanurate derivative has a structure in which an ethylenic unsaturated group is bonded to all three nitrogen atoms of the isocyanuric acid skeleton. 3. The method according to claim 1 or 2, And a pencil hardness of 2H or more. 3. The method according to claim 1 or 2, Wherein the base film is a triacetylcellulose film having a thickness of 80 占 퐉 or less. 3. The method according to claim 1 or 2, Wherein the hard coating layer has a thickness of 3 to 10 mu m. 3. The method according to claim 1 or 2, Wherein the component (A) is pentaerythritol triacrylate, pentaerythritol tetraacrylate or dipentaerythritol hexaacrylate. 3. The method according to claim 1 or 2, Wherein the component (B) is tris (2-acryloyloxyethyl) isocyanurate.