JP5047636B2 - Hard coat film - Google Patents

Description

  The present invention relates to a hard coat film, and more particularly to a hard coat film having a necessary and sufficient surface hardness as a surface protective film for various image display devices and having a small warp (curl) due to curing shrinkage.

Conventionally, hard coat films have been used for various image display devices such as LCD (liquid crystal display), touch panel, CRT (CRT), PDP (Plasma Display Panel), EL (Electroluminescence), etc., as well as anti-glare properties. It is used for purposes such as antireflection. Moreover, in LCD, it is used in order to protect a polarizer. This hard coat film generally has a hard coat layer formed on a base film by heat curing or active energy ray curing.
On the other hand, in recent years, there has been a demand for thinner image display devices. In this case, it is desired to use a base film having a thickness about half of the conventional thickness (about 80 to 125 μm) for the hard coat film. However, when a conventional hard coat layer is formed on such a thin base film, curling occurs on the hard coat film due to curing shrinkage of the hard coat layer, and as a result, it is used as a surface protective film. Cause unfavorable situations such as difficulty.
Therefore, a curable composition containing a compound having three or more ethylenically unsaturated groups and one or more isocyanurate rings in the same molecule is suppressed on the substrate in order to suppress curing shrinkage and curl generation. There is disclosed a hard coat treated article that is coated and cured, and the hard coat layer after curing has a film thickness of 15 μm or more and 200 μm or less (see, for example, Patent Document 1). However, in this case, in order to obtain sufficient hardness, there is a problem that the thickness of the hard coat layer must be set large.
Moreover, the technique which hardens the composition containing the isocyanurate derivative which has two ethylenically unsaturated groups, and a pentaerythritol acrylate and makes it a hard-coat layer is disclosed (for example, refer patent document 2). However, in this technique, since the hardness of the cured product of the isocyanurate derivative alone is insufficient, there is room for further improvement with respect to the hardness of the hard coat layer obtained by curing the composition.
JP 2004-141732 A JP 2005-109773 A

  Under such circumstances, the present invention has been made for the purpose of providing a hard coat film having a necessary and sufficient surface hardness as a surface protective film for various image display devices and having a small warpage due to curing shrinkage. Is.

As a result of intensive studies to develop a hard coat film having the above-mentioned preferable properties, the present inventors have obtained an active energy ray-curable compound and an active energy ray-curable isocyanurate derivative each having a specific structure. Based on this finding, the hard coat layer forming material contained at a predetermined ratio is used, and the objective can be achieved by providing a hard coat layer comprising an active energy ray-curable resin layer on the base film. The present invention has been completed.
That is, the present invention
[1] On a base film which is a triacetyl cellulose film having a thickness of 80 μm or less, component (A) ; active energy rays other than an isocyanurate derivative having three or more ethylenically unsaturated groups in the molecule Active energy ray-curable isocyanurate having a structure in which an ethylenically unsaturated group is bonded to all three nitrogen atoms of the isocyanuric acid skeleton with respect to 100 parts by mass of the curable compound and its component (B) Hard having a hard coat layer having a thickness of 3 to 10 μm made of an active energy ray-curable resin layer formed using a hard coat layer forming material containing 180 to 520 parts by mass of a derivative , and cut into 10 cm square The total of the four curl heights generated when the coated film is placed on a flat plate is 100 mm or less, and the pencil hardness is 2H or more. Features hard coat film,
[2] The hard coat film according to the above [1] , wherein the component (A) is pentaerythritol triacrylate, pentaerythritol tetraacrylate or dipentaerythritol hexaacrylate , and [3] the component (B) is tris (2 -A hard coat film according to the above [1] or [2], which is -acryloyloxyethyl) isocyanurate ,
Is to provide.

  ADVANTAGE OF THE INVENTION According to this invention, it can provide the hard coat film which has surface hardness required and sufficient as a surface protection film of various image display apparatuses, and has little curvature by hardening shrinkage.

The hard coat film of the present invention uses a hard coat layer forming material containing (A) an active energy ray-curable compound other than an isocyanurate derivative and (B) an active energy ray-curable isocyanurate derivative on a base film. And a hard coat layer made of an active energy ray-curable resin layer.
There is no restriction | limiting in particular in the base film used in the hard coat film of this invention, It can select and use suitably from well-known plastic films as a base material of the hard coat film for conventional optics. Examples of such plastic films include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyethylene films, polypropylene films, cellophane, diacetyl cellulose films, triacetyl cellulose films, acetyl cellulose butyrate films, and polychlorinated. Vinyl film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyether ether ketone film, polyether sulfone film, polyetherimide film , Polyimide film, fluororesin film, Li amide film, acrylic resin film, norbornene resin film, a cycloolefin resin film.
These base films may be either transparent or translucent, may be colored, or may be uncolored, and may be appropriately selected depending on the application. For example, when used for protecting a polarizer of a liquid crystal display, a colorless and transparent triacetylcellulose film is suitable.

The thickness of these base films is not particularly limited and is appropriately selected depending on the situation. From the viewpoint of effectively exhibiting the curling generation suppressing effect, it is preferably 80 μm or less, more preferably 20 to 80 μm. Range. Moreover, this base film can be surface-treated by an oxidation method, a concavo-convex method, or the like on one side or both sides as desired for the purpose of improving adhesion to a layer provided on the surface. Examples of the oxidation method include corona discharge treatment, plasma treatment, chromic acid treatment (wet), flame treatment, hot air treatment, ozone / ultraviolet irradiation treatment, and examples of the unevenness method include a sand blast method, a solvent, and the like. Treatment methods and the like. These surface treatment methods are appropriately selected according to the type of the base film, but generally, the corona discharge treatment method is preferably used from the viewpoints of effects and operability.
In the hard coat film of the present invention, the hard coat layer laminated on the base film has (A) an active energy other than an isocyanurate derivative having three or more ethylenically unsaturated groups in the molecule. It is formed by a hard coat layer forming material containing a linear curable compound and (B) an active energy ray curable isocyanurate derivative having 3 or more ethylenically unsaturated groups in the molecule.

The active energy ray-curable compound in the component (A) is a compound having energy quanta in an electromagnetic wave or a charged particle beam, that is, a compound that is crosslinked and cured by irradiation with ultraviolet rays or electron beams. Point to. Of course, the component (B) is also a kind of active energy ray-curable compound.
This active energy ray-curable compound of component (A) is a compound having three or more ethylenically unsaturated groups in the molecule and other than the isocyanurate derivative. Such compounds include, for example, trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide modified tri Trifunctional (meth) acrylates such as methylolpropane tri (meth) acrylate, propionic acid modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate and caprolactone modified dipentaerythritol hexa (meth) acrylate Can be mentioned. These may be used individually by 1 type and may be used in combination of 2 or more type. The number of ethylenically unsaturated groups is not particularly limited as long as it is 3 or more, but 3 to 6 is preferable from the viewpoint of curling suppression.

（式中、Ａ¹〜Ａ³は、それぞれ独立に(メタ)アクリロイルオキシ基、Ｒ¹〜Ｒ³は、それぞれ独立に炭素数２〜４のアルキレン基を示す。）
で表されるトリス[(メタ)アクリロイルオキシアルキル]イソシアヌレートを挙げることができる。
前記一般式（Ｉ）において、Ｒ¹〜Ｒ³で示されるアルキレン基は直鎖状、分岐鎖状のいずれであってもよく、具体的にはエチレン基、プロピレン基、トリメチレン基、各種ブチレン基が挙げられる。また、３つの窒素原子に結合した(メタ)アクリロイルオキシアルキル基は、たがいに同一であってもよく、異なっていてもよい。
前記一般式（Ｉ）で表されるトリス[(メタ)アクリロイルオキシアルキル]イソシアヌレートとしては、例えばトリス(２−アクリロイルオキシエチル)イソシアヌレート、トリス(３−アクリロイルオキシプロピル)イソシアヌレート、トリス(２−メタクリロイルオキシエチル)イソシアヌレート、トリス(３−メタクリロイルオキシプロピル)イソシアヌレートなどを好ましく挙げることができる。
本発明においては、（Ｂ）成分として、これらの化合物は１種を単独で用いてもよく、２種以上を組み合わせて用いてもよい。また、ハードコート層形成材料における当該（Ｂ）成分の含有量は、前記（Ａ）成分１００質量部に対して、１５０〜５５０質量部の範囲で選定される。この含有量が１５０質量部未満では、得られるハードコートフィルムのカール抑制効果が十分に発揮されないし、５５０質量部を超えるとハードコートフィルムの表面硬度が低下する。カール発生の抑制効果及び表面硬度のバランスなどの観点から、（Ｂ）成分の好ましい含有量は、１８０〜５２０質量部の範囲である。 On the other hand, the active energy ray-curable isocyanurate derivative having 3 or more ethylenically unsaturated groups in the molecule as the component (B) has 3 or more ethylenically unsaturated groups in the isocyanuric acid skeleton. There is no particular limitation as long as it is a compound having a bonded structure, but from the viewpoint of performance and ease of production, etc., a structure in which an ethylenically unsaturated group is bonded to all three nitrogen atoms of the isocyanuric acid skeleton. Those are preferred. As the ethylenically unsaturated group, a (meth) acryloyloxy group is preferable. Examples of such isocyanurate derivatives include those represented by the general formula (I)

(In the formula, A ^{1 to} A ³ each independently represents a (meth) acryloyloxy group, and R ^{1 to} R ³ each independently represents an alkylene group having 2 to 4 carbon atoms.)
And tris [(meth) acryloyloxyalkyl] isocyanurate represented by the formula:
In the general formula (I), the alkylene group represented by R ^{1 to} R ³ may be linear or branched, and specifically includes an ethylene group, a propylene group, a trimethylene group, and various butylene groups. Is mentioned. In addition, the (meth) acryloyloxyalkyl groups bonded to the three nitrogen atoms may be the same or different.
Examples of the tris [(meth) acryloyloxyalkyl] isocyanurate represented by the general formula (I) include tris (2-acryloyloxyethyl) isocyanurate, tris (3-acryloyloxypropyl) isocyanurate, and tris (2 Preferred examples include -methacryloyloxyethyl) isocyanurate, tris (3-methacryloyloxypropyl) isocyanurate and the like.
In the present invention, as the component (B), these compounds may be used alone or in combination of two or more. Moreover, content of the said (B) component in a hard-coat layer forming material is selected in the range of 150-550 mass parts with respect to 100 mass parts of said (A) component. When the content is less than 150 parts by mass, the curl suppressing effect of the obtained hard coat film is not sufficiently exhibited, and when the content exceeds 550 parts by mass, the surface hardness of the hard coat film is lowered. From the viewpoint of curling generation suppression effect and balance of surface hardness, the preferred content of component (B) is in the range of 180 to 520 parts by mass.

In addition to the components (A) and (B), the hard coat layer forming material may contain other active energy ray-curable compounds as necessary within the range that does not impair the object of the present invention. Can do.
Examples of other active energy ray-curable compounds include active energy ray polymerizable prepolymers and / or active energy ray polymerizable monofunctional monomers and bifunctional monomers.
Examples of the active energy ray polymerizable prepolymer include polyester acrylate, epoxy acrylate, urethane acrylate, and polyol acrylate.
On the other hand, as the active energy ray polymerizable monofunctional monomer, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) At least one selected from acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isobornyl (meth) acrylate, and the like can be appropriately selected and used.
Examples of the active energy ray polymerizable bifunctional monomer include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and polyethylene glycol diester. (Meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl di (meth) acrylate, ethylene oxide modified di (meth) acrylate phosphoric acid, allylation Appropriate selection of at least one selected from cyclohexyl di (meth) acrylate, bis [2- (meth) acryloxyethyl] isocyanurate, bis [2- (meth) acryloxyethyl] 2-hydroxyethyl isocyanurate, etc. Can be used as .

  The hard coat layer forming material can contain a photopolymerization initiator. Examples of this 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 phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl]- 2-morpholino-propan-1-one, 4- (2-hydroxyethoxy) phenyl-2 (hydroxy-2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4′-diethylaminobenzophenone Dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4 -Diethylthioxanthone, benzyl dimethyl ketal, acetophenone dimethyl ketal, p-dimethylamine benzoate and the like. These may use 1 type and may use it in combination of 2 or more type, The compounding quantity is the range of 0.2-10 mass parts normally with respect to 100 mass parts of active energy ray hardening-type compounds. Selected.

The hard coat layer forming material can 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 methyl ethyl ketone, 2-pentanone, isophorone and cyclohexanone, esters such as ethyl acetate and butyl acetate, cellosolv solvents such as ethyl cellosolve, glycol ether solvents such as propylene glycol monomethyl ether, and the like. These solvents may be used alone or in a combination of two or more.
In addition, various additive components such as fillers for imparting antiglare properties, reactive silicone compounds, photosensitizers, polymerization inhibitors, crosslinking agents, antioxidants, ultraviolet absorbers, light stabilizers, leveling agents, quenching agents. A foaming agent etc. can be contained suitably.

As the filler for imparting antiglare property, an arbitrary one can be appropriately selected from those conventionally known as fillers for imparting antiglare property. Examples of such a filler include silica particles having an average particle diameter of about 1.5 to 7 μm, aggregates of colloidal silica particles with an amine compound, and having an average particle diameter of about 0.5 to 10 μm, or Examples thereof include a mixture of silica particles having an average particle size of about 0.5 to 5 μm 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 suitably selected in consideration of the antiglare performance and scratch resistance of the obtained hard coat film.
Moreover, as a reactive silicone compound, the silicone compound which has a radically polymerizable unsaturated group in a molecule | numerator can be used. This silicone compound is crosslinked and cured by irradiation with active energy rays, and has an action of imparting stain resistance, low friction properties and the like to the hard coat layer.

In the present invention, a hard coat layer forming material (coating liquid) containing each of the components described above and adjusted to a concentration suitable for coating is prepared, and a conventionally known method such as a bar is prepared on the base film. Using a coating method, knife coating method, roll coating method, blade coating method, die coating method, gravure coating method, etc. to form a undried coating film by coating so that the thickness after curing reaches a predetermined value. After that, after a drying treatment at about 60 to 130 ° C. for about 1 to 3 minutes, the hard coating layer is formed by irradiating the dry coating film with active energy rays and curing the coating film.
Examples of the active energy rays include ultraviolet rays and electron beams. The ultraviolet rays are obtained with a high-pressure mercury lamp, a fusion H lamp, a xenon lamp or the like, and the irradiation amount is usually 100 to 500 mJ / cm ² , while the electron beam is obtained with an electron beam accelerator or the like, Usually 150 to 350 kV. Among these active energy rays, ultraviolet rays are particularly preferable. In addition, when using an electron beam, a cured film can be obtained, without adding a photoinitiator.
The thickness of the hard coat layer is usually about 3 to 10 μm. In the hard coat film obtained in this way, the total of the curl heights of the four corners that normally occur when the hard coat film cut into 10 cm square is placed on a flat plate is 100 mm or less, The pencil hardness is 2H or more. The method for 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 provided on the hard coat layer as necessary. There is no restriction | limiting in particular in the formation method of this transparent conductive thin film layer, For example, physical vapor deposition methods (PVD method), such as sputtering, etc. can be employ | adopted conventionally.
Examples of the material for 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.
Since the hard coat film of the present invention having a hard coat layer provided with a transparent conductive thin film layer on the surface has high scratch resistance of the hard coat layer, the hard coat film is used as a touch side in a resistive film type touch panel. By applying to the transparent plastic substrate, it is possible to solve the problems that the transparent conductive thin film of the touch side transparent plastic substrate is worn, cracked, or peeled off from the base material.

In the present invention, if necessary, an antireflection layer such as a siloxane coating or a fluorine coating can be provided on the surface of the hard coat layer for the purpose of imparting antireflection properties. In this case, the thickness of the antireflection layer is suitably about 0.05 to 0.2 μm. The reflectance at a wavelength of 550 nm is preferably 3.5% or less. By providing this anti-reflective layer, screen reflections caused by reflection from sunlight, fluorescent lamps, etc. are eliminated, and by suppressing the reflectance of the surface, the total light transmittance is increased and the transparency is improved. .
In this invention, the adhesive layer for making it adhere to a to-be-adhered body can be formed in the surface on the opposite side to the hard-coat layer of a base film. As an adhesive which comprises this adhesive layer, the thing for optical uses, for example, an acrylic adhesive, a urethane type adhesive, and a silicone type adhesive, are used preferably. The thickness of this pressure-sensitive adhesive layer is usually 5 to 100 μm, preferably 10 to 60 μm.
Furthermore, a release sheet can be provided on the pressure-sensitive adhesive layer as necessary. Examples of the release sheet include papers such as glassine paper, coated paper, and laminate paper, and various plastic films coated with a release agent such as a silicone resin. Although there is no restriction | limiting in particular about the thickness of this peeling sheet, Usually, it is about 20-150 micrometers.
The hard coat film of the present invention has a necessary and sufficient surface hardness as a surface protective film for various image display devices, and has little warpage due to curing shrinkage.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
In addition, the performance of the hard coat film obtained in each example was evaluated according to the following method.
(1) Pencil hardness Using a pencil scratch coating film hardness tester [manufactured by Toyo Seiki Seisakusho, model “NP”], the pencil hardness was measured in accordance with JIS K 5600-5-4.
(2) Curl A hard-coated film is cut into a 10cm square and a test piece is prepared. After standing for 24 hours in an environment of 23 ° C and relative humidity (RH) 55%, the test piece is placed on a horizontal glass plate. It was placed so that the upper side was concave, and the lifting of the four corners was measured with a ruler, and the total value was obtained.

Preparation Example 1 Preparation of Coating Liquid A (A) Pentaerythritol triacrylate [manufactured by Shin-Nakamura Chemical Co., Ltd., trade name “NK Ester A-TMM-3”, solid content concentration 100%] B) Tris (2-acryloyloxyethyl) isocyanurate [manufactured by Toa Gosei Chemical Co., Ltd., trade name “Aronix M-315”, solid content concentration 100%] 200 parts by mass, 1-hydroxy- as a photopolymerization initiator Add 6 parts by mass of cyclohexyl phenyl ketone [trade name “Irgacure 184” manufactured by Ciba Specialty Chemicals Co., Ltd.] and dilute with propylene glycol monomethyl ether so that the solid content concentration is 40% by mass. Was prepared.
Preparation Example 2 Preparation of Coating Solution B In Preparation Example 1, the amount of (B) tris (2-acryloyloxyethyl) isocyanurate was changed to 500 parts by mass, and the amount of 1-hydroxy-cyclohexyl phenyl ketone was changed to 12 parts by mass. A coating solution B was prepared in the same manner as in Preparation Example 1 except that.
Preparation Example 3 Preparation of Coating Liquid C In Preparation Example 1, (A) pentaerythritol triacrylate was changed to pentaerythritol tetraacrylate [manufactured by Shin-Nakamura Chemical Co., Ltd., trade name “NK Ester A-TMMT”, solid concentration 100 %] Was applied in the same manner as in Preparation Example 1, except that the coating liquid C was prepared.
Preparation Example 4 Preparation of Coating Liquid D A coating liquid D was prepared in the same manner as in Preparation Example 2, except that (A) pentaerythritol triacrylate was changed to pentaerythritol tetraacrylate (described above) in Preparation Example 2. .
Preparation Example 5 Preparation of Coating Liquid E In Preparation Example 1, (A) pentaerythritol triacrylate was changed to dipentaerythritol hexaacrylate [manufactured by Toagosei Chemical Co., Ltd., trade name “Aronix M-400”, solid concentration 100 %] Was applied in the same manner as in Preparation Example 1, except that the coating liquid E was prepared.
Preparation Example 6 Preparation of Coating Liquid F Preparation Example 2 was followed in the same manner as Preparation Example 2 except that (A) pentaerythritol triacrylate was changed to dipentaerythritol hexaacrylate (supra). did.
Preparation Example 7 Preparation of Coating Solution G Coating Sample G was prepared in the same manner as Preparation Example 1 except that the amount of (B) tris (2-acryloyloxyethyl) isocyanurate was changed to 350 parts by mass. Was prepared.
Preparation Example 8 Preparation of Coating Liquid H In Preparation Example 1, the amount of (B) tris (2-acryloyloxyethyl) isocyanurate was changed to 100 parts by mass, and the amount of 1-hydroxy-cyclohexyl phenyl ketone was changed to 5 parts by mass. A coating solution H was prepared in the same manner as in Preparation Example 1 except that.
Preparation Example 9 Preparation of Coating Liquid I A coating liquid I was prepared in the same manner as in Preparation Example 8 except that (A) pentaerythritol triacrylate was changed to dipentaerythritol hexaacrylate (supra) in Preparation Example 8. did.
Preparation Example 10 Preparation of Coating Liquid J In Preparation Example 1, the amount of (B) tris (2-acryloyloxyethyl) isocyanurate was changed to 600 parts by mass, and the amount of 1-hydroxy-cyclohexyl phenyl ketone was changed to 14 parts by mass. A coating solution J was prepared in the same manner as in Preparation Example 1 except that.
Preparation Example 11 Preparation of Coating Liquid K In Preparation Example 10, a coating liquid K was prepared in the same manner as in Preparation Example 10 except that (A) pentaerythritol triacrylate was changed to dipentaerythritol hexaacrylate (described above). did.

Example 1
Using a bar coater, the coating liquids A to G prepared in Preparation Examples 1 to 7 on a triacetyl cellulose film [Fuji Photo Film Co., Ltd., trade name “T40UZ”] having a thickness of 40 μm as a base film. Then, the coated film was coated so that the thickness after drying was 3 μm, dried at 70 ° C. for 1 minute, and then cured by irradiating the coated surface with ultraviolet light at a light amount of 230 mJ / cm ² to prepare each hard coat film. The thickness of the hard coat layer was 3 μm.
The performance evaluation results of each hard coat film are shown in Table 1.
Example 2
In Example 1, each hard coat film was produced like Example 1 except having applied so that the thickness after drying might be set to 6 micrometers. The thickness of the hard coat layer was 6 μm.
The performance evaluation results of each hard coat film are shown in Table 1.
Example 3
In Example 1, each hard coat film was produced like Example 1 except having applied so that the thickness after drying might be set to 10 micrometers. The thickness of the hard coat layer was 10 μm.
The performance evaluation results of each hard coat film are shown in Table 1.

Comparative Example 1
The coating liquids H and I prepared in Preparation Examples 8 and 9 are dried on a triacetyl cellulose film (supra) having a thickness of 40 μm as a base film using a bar coater so that the thickness after drying becomes 6 μm. After coating at 70 ° C. for 1 minute, the coated surface was cured by irradiating the coated surface with ultraviolet light at a light intensity of 230 mJ / cm ² to prepare each hard coat film.
The performance evaluation results of each hard coat film are shown in Table 1.
Comparative Example 2
A coating film J, K prepared in Preparation Examples 10 and 11 on a 40 μm thick triacetyl cellulose film (supra) as a base film so that the thickness after drying using a bar coater is 6 μm. After coating at 70 ° C. for 1 minute, the coated surface was cured by irradiating the coated surface with ultraviolet light at a light intensity of 230 mJ / cm ² to prepare each hard coat film.
The performance evaluation results of each hard coat film are shown in Table 1.

As can be seen from Table 1, all of the hard coat films (Examples 1 to 3) of the present invention have a pencil hardness of 2H or more and a curl amount (total of four corners) of less than 100 mm.
On the other hand, although the comparative example 1 has a high pencil hardness of 2H or higher, the curl amount is large and rejected, and the comparative example 2 has a small curl amount, but the pencil hardness is H and rejected.

  The hard coat film of the present invention has a necessary and sufficient surface hardness as a surface protective film for various image display devices, and is less warped due to curing shrinkage, for example, for touch panels, polarizing plates, quarter-wave plates, or It is suitably used as a cover film for optical discs and protective films for various displays.

Claims (3)

On the base film which is a triacetyl cellulose film having a thickness of 80 μm or less, component (A) ; active energy ray-curable compound having 3 or more ethylenically unsaturated groups in the molecule and other than isocyanurate derivatives And 100 parts by mass of the component (B) ; an active energy ray-curable isocyanurate derivative 180- having a structure in which an ethylenically unsaturated group is bonded to all three nitrogen atoms of the isocyanuric acid skeleton. A hard coat film formed using a hard coat layer forming material containing 520 parts by mass, having a hard coat layer made of an active energy ray-curable resin layer and having a thickness of 3 to 10 μm, cut into a 10 cm square. The total of the curl height of the four corners generated when placed on a flat plate is 100 mm or less, and the pencil hardness is 2H or more. Hard coat film. The hard coat film according to claim 1 , wherein the component (A) is pentaerythritol triacrylate, pentaerythritol tetraacrylate, or dipentaerythritol hexaacrylate . The hard coat film according to claim 1 or 2 , wherein the component (B) is tris (2-acryloyloxyethyl) isocyanurate .