JP2009057504A - Hard coat film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hard coat film which is provided on a triacetyl cellulose substrate with a hard coat layer and which has a higher surface hardness at the side provided with the hard coat layer and which has a smaller degree of the curling of the hard coat film even when setting a heating process as the after step. <P>SOLUTION: The hard coat film, which is provided on at least one side surface of a triacetyl cellulose substrate with a hard coat layer, is characterized in that the above hard coat layer is a product by curing a polymer compound having a carbon-carbon unsaturated bond at the side chain and a glass transition temperature of 70°C or higher and a multifunctional acrylate by means of an ionizing radiation. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hard coat film provided on the surface of a window or a display. In particular, the present invention relates to a hard coat film provided on the surface of a display such as a liquid crystal display (LCD), a CRT display, an organic electroluminescence display (ELD), a plasma display (PDP), a surface electric field display (SED), or a field emission display (FED). . In particular, it relates to a hard coat film provided on the surface of a liquid crystal display.

  Conventionally, a transparent plastic film having scratch resistance and scratch resistance is often attached to an optical member provided on the surface of a display such as a liquid crystal display (LCD). In general, as a technique for hardening the plastic surface, a method of coating a thermosetting resin such as an organosiloxane type or a melamine type, a method of forming a metal thin film by a vacuum deposition method or a sputtering method, or a polyfunctional acrylate There is a method of coating an ionizing radiation curable resin.

  In recent years, among these methods, ionizing radiation curable materials that are easy to process large areas and are excellent in productivity are often used. However, in any of these methods, the pencil hardness value of the hard coat film that can be realized is within the range where there is no practical problem such as adhesion between the hard coat layer and the base material, cracking when the film is folded, curl of the film, etc. In many cases, 2H to 3H is the limit. In particular, the curl of the film increases as the surface hardness after coating increases.

  As described above, the curl of the film is contraction due to the acrylic resin double bond becoming a single bond by polymerization. Therefore, the higher the hardness, the larger the curl. When the curl is large, the productivity in the bonding process to the display surface in the next process or the durability after bonding is remarkably lowered. Therefore, when a hard coat layer formed by curing an ionizing radiation curable material is provided on the film, it is necessary to limit the thickness of the hard coat layer and the crosslinking reaction rate.

On the other hand, as a method of suppressing curling of the film, a method of mixing a resin having a certain large molecular weight in addition to an acrylic resin-based oligomer or monomer (see, for example, Patent Document 1), and a method of reducing curl as colloidal silica. A method for reducing curl by adding particles or silica sol to an acrylic resin monomer or oligomer (for example, Patent Documents 2 to 4) is disclosed. However, when using colloidal silica particles or silica sol, it is necessary to use particles having a particle size smaller than the visible light wavelength in order to maintain transparency, and the effect of relaxing the stress inside the hard coat layer is Absent.
JP 2003-301008 A JP 2001-113649 A Japanese Patent Application Laid-Open No. 2004-117499 JP 2004-182765 A

  The curling of the hard coat film is a serious problem particularly when a heating process is required in the subsequent process of the hard coat film. That is, when the obtained hard coat film is heated, the degree of curling becomes large, and there arises a problem that productivity in the bonding process or durability after bonding is remarkably deteriorated. In the present invention, in a hard coat film provided with a hard coat layer on a triacetyl cellulose substrate, the surface hardness on the side where the hard coat layer is provided is high, and even when a heating step is provided as a subsequent step It is an object of the present invention to provide a hard coat film with a small degree of curl of the hard coat film.

  In order to solve the above-mentioned problem, the invention according to claim 1 is a hard coat film including a hard coat layer on at least one surface of a triacetyl cellulose base material, and the hard coat layer is carbon in a side chain. -A hard coat film comprising a polymer compound having a carbon unsaturated bond and a glass transition temperature of 70C or higher and a polyfunctional acrylate cured by ionizing radiation.

  The invention according to claim 2 is characterized in that the polymer compound has an acryloyl group or a methacryloyl group in a side chain, and a saturated aliphatic ring in the side chain. It was.

  The invention according to claim 3 is characterized in that the polymer compound is contained in the hard coat layer in the range of 10 to 40 parts by weight. The hard coat film described was used.

  The invention according to claim 4 is characterized in that the hard coat layer contains a photopolymerization initiator, and the photopolymerization initiator is acylphosphine oxide. It was set as the hard coat film of 1 item | term.

  The invention according to claim 5 is the hard coat film according to any one of claims 1 to 4, wherein the polyfunctional acrylate is a polyfunctional urethane acrylate.

  The invention according to claim 6 is the hard coat film according to any one of claims 1 to 5, wherein the thickness of the hard coat layer is 5 μm or more and 15 μm or less.

  The invention according to claim 7 is the hard coat film according to any one of claims 1 to 6, wherein the hard coat film does not contain a filler.

（式中、Ｒ_１はメチル基または水素原子を示し、Ｒ_２は、アルキル基、アリール基、ヒドロキシアルキル基、水素原子等から選ばれた置換基を示し、Ｒ_３は、脂環を含み、末端に−Ｃ＝ＣＨ_２基を有する残基を示す。ｍ＋ｎ＝１である。） The invention according to claim 8 is a hard coat film comprising a hard coat layer on at least one surface of a triacetyl cellulose base material, wherein the hard coat layer is a polymer represented by (Chemical Formula 2) A hard coat film is obtained by curing a compound and a polyfunctional acrylate.

(Wherein R ₁ represents a methyl group or a hydrogen atom, R ₂ represents a substituent selected from an alkyl group, an aryl group, a hydroxyalkyl group, a hydrogen atom, etc., and R ₃ includes an alicyclic ring, A residue having a —C═CH ₂ group at the terminal is shown. M + n = 1.)

  The invention according to claim 9 is a liquid crystal display including the hard coat film according to any one of claims 1 to 8.

  By using the hard coat film having the above-described structure, the surface hardness on the side where the hard coat layer is provided is high, and even when a heating step is provided as a subsequent step, the degree of curling of the hard coat film is small. A coated film could be obtained.

The present invention will be described below.
FIG. 1 is an explanatory sectional view of the hard coat film of the present invention.
The hard coat film (1) of the present invention comprises a hard coat layer (12) on at least one surface of a triacetyl cellulose substrate (11).

  A commercially available triacetyl cellulose film can be used as the triacetyl cellulose substrate that can be used in the present invention. The triacetyl cellulose film can be suitably used for a liquid crystal display because it has a small birefringence and good transparency. Note that. The thickness of the triacetyl cellulose base material is preferably in the range of 25 μm to 200 μm, and more preferably in the range of 40 μm to 80 μm.

  In the hard coat layer of the present invention, a polymer compound having a carbon-carbon unsaturated bond in the side chain and a glass transition temperature of 70 ° C. or higher and a polyfunctional acrylate were cured by ionizing radiation. It is characterized by being.

  In the hard coat layer of the present invention, the polymer compound used has a carbon-carbon unsaturated bond in the side chain, thereby reacting with a polyfunctional acrylate upon curing with ionizing radiation to form a matrix. Can do. When a polymer compound having no carbon-carbon unsaturated bond in the side chain is used, curling of the formed hard coat film can be suppressed, but the hardness of the formed hard coat layer is significantly reduced. .

  In the hard coat layer of the present invention, the polymer compound used has a glass transition temperature of 70 ° C. or higher. By setting the glass transition temperature of the polymer compound to 70 ° C. or higher, it is possible to prevent curling of the hard coat film due to heating when the hard coat film provided with the hard coat layer has a heating process as a subsequent process. . In the case where a hard coat layer is formed using a polymer compound having a glass transition temperature of less than 70 ° C., curling occurs when the hard coat film is subjected to a heat treatment as a subsequent process, and therefore a bonding process. Productivity decreases.

  Moreover, in the polymer compound used when forming the hard coat layer of the present invention, it is preferable that the side chain has an acryloyl group or a methacryloyl group, and the side chain has a saturated aliphatic ring. It is possible to suppress curling by adding a polymer compound, but furthermore, by having an acryloyl group or methacryloyl in the side chain, it can react with a polyfunctional acrylate during curing to form a matrix. Moreover, the fall of the hardness of the hard-coat layer by adding a high molecular compound can be suppressed. Moreover, by setting it as a high molecular compound which has a saturated aliphatic ring in a side chain, the glass transition temperature of a high molecular compound can be 70 degreeC or more, without raising the refractive index of the hard coat film formed. .

  When a hard coat film is formed using a polymer compound having an unsaturated aliphatic ring such as a benzene ring, the polymer compound is the same as in the case of using a polymer compound having a saturated aliphatic ring. It is possible to prevent the hard coat film from curling due to heating by setting the glass transition temperature to 70 ° C. or higher. However, since the unsaturated aliphatic ring increases the refractive index of the hard coat layer, the refractive index difference between the refractive index of the hard coat layer and the refractive index of the triacetyl cellulose substrate tends to increase. And when the refractive index difference of the refractive index of a hard-coat layer and the refractive index of a triacetyl cellulose base material increases, an interference fringe may generate | occur | produce in the hard coat film obtained. Therefore, in the polymer compound used when forming the hard coat layer of the present invention, it is preferable to provide a saturated aliphatic ring in the side chain.

  Moreover, it is preferable that content of the high molecular compound used for the hard-coat layer of this invention is 10 to 40 weight part with respect to hard-coat layer solid content. If it is less than 10 parts by weight, the effect of curling relaxation may not be sufficiently obtained. On the other hand, if it is 40 parts by weight or more, the film strength, that is, a high hardness hard coat layer may not be obtained.

  Moreover, in the hard coat film used for this invention, it is preferable that the thickness of the hard coat film layer formed is 5 micrometers or more and 15 micrometers or less. When the thickness of the hard coat layer is less than 5 μm, sufficient surface hardness may not be obtained in the hard coat layer. Further, when the thickness of the hard layer exceeds 15 μm, the curl tends to become intense regardless of the presence or absence of heating. A more preferable thickness of the hard coat layer is 6 μm or more and 12 μm or less. As for the hard coat film of this invention, it is desirable that the pencil hardness of JISK5400 regulation of a hard-coat layer formation surface is 3H or more.

  Further, in the hard coat layer of the hard coat film of the present invention, fillers such as organic particles and inorganic particles for suppressing curling or increasing the hardness of the hard coat layer surface cause a decrease in transmittance. It is preferable not to add it. Further, when a hard coat film having a hard coat layer on the surface is subjected to an alkali treatment, a problem may occur. In the present invention, even when no filler is added to the hard coat layer, the surface hardness is high, and the degree of curling of the hard coat film is small even when a heating step is provided as a subsequent step. A hard coat film can be provided.

  The hard coat film of the present invention is formed by applying a coating liquid for forming a hard coat layer containing a polymer compound and a polyfunctional acrylate on a triacetyl cellulose base material and curing it by ultraviolet or electron beam ionizing radiation. can do. At this time, the coating liquid may contain a photopolymerization initiator, a solvent, or the like as necessary.

  As the polyfunctional acrylate contained in the hard coat layer forming coating solution, known ones can be used. The polyfunctional acrylate may be a monomer or an oligomer. In particular, among polyfunctional acrylates, the desired molecular weight and molecular structure can be designed, and the polyfunctional urethane acrylate is preferably used because the physical properties of the formed hard coat layer can be easily balanced. Can do. Urethane acrylate oligomer and monomer can be obtained by reacting polyhydric alcohol, polyvalent isocyanate and hydroxyl group-containing acrylate, but when hard coat layer is formed with urethane acrylate alone without polymer compound, hard coat layer surface It is preferable to use one that can achieve a pencil hardness of 4H. Specifically, Kyoeisha Chemical Co., Ltd., UA-306H, UA-306T, UA-306l, etc., Nippon Synthetic Chemical Co., Ltd., UV-1700B, UV-6300B, UV-7600B, UV-7605B, UV-7640B, UV -7650B, etc., Shin-Nakamura Chemical Co., Ltd., U-4HA, U-6HA, UA-100H, U-6LPA, U-15HA, UA-32P, U-324A, etc., Daicel UCB, Ebecryl-1290, Ebecryl -1290K, Ebecryl-5129, etc., manufactured by Negami Kogyo Co., Ltd., UN-3220HA, UN-3220HB, UN-3220HC, UN-3220HS, etc. can be mentioned, but not limited thereto.

  As described above, it is necessary to use a polymer compound having a carbon-carbon unsaturated bond in the side chain and a glass transition temperature of 70 ° C. or higher as the polymer compound contained in the hard coat layer forming coating solution. Furthermore, it is preferable to use a polymer compound having an acryloyl group or a methacryloyl group in the chain and a saturated aliphatic ring in the side chain.

（式中、Ｒ_１はメチル基または水素原子を示し、Ｒ_２は、アルキル基、アリール基、ヒドロキシアルキル基、水素原子等から選ばれた置換基を示し、Ｒ_３は、飽和脂肪族環を含み、末端にアクリロイル基若しくはメタクリロイル基を有する残基を示す。ｍ＋ｎ＝１である。）
上記のように、極性基を有する高分子化合物を用いることにより、トリアセチルセルロース基材とハードコートフィルムとの密着性を向上させることができる。 Examples of the polymer compound used in the hard coat layer of the present invention include the polymer compound represented by (Chemical Formula 3).

(Wherein R ₁ represents a methyl group or a hydrogen atom, R ₂ represents a substituent selected from an alkyl group, an aryl group, a hydroxyalkyl group, a hydrogen atom, etc., and R ₃ represents a saturated aliphatic ring. And a residue having an acryloyl group or a methacryloyl group at the terminal (m + n = 1).
As described above, the adhesion between the triacetylcellulose substrate and the hard coat film can be improved by using the polymer compound having a polar group.

（式中、Ｒ_１はメチル基または水素原子を示し、Ｒ_２は、アルキル基、アリール基、ヒドロキシアルキル基等から選ばれた置換基を示し、ｍ＋ｎ＝１である。）具体的な高分子化合物としては、ダイセル化学工業社製サイクロマーＰを挙げることが出来るが、この限りではない。 As a polymer compound used in the hard coat layer of the present invention, a polymer compound represented by (Chemical Formula 4) can be exemplified as a more preferable polymer compound.

(Wherein R ₁ represents a methyl group or a hydrogen atom, R ₂ represents a substituent selected from an alkyl group, an aryl group, a hydroxyalkyl group, etc., and m + n = 1). Examples of the compound include Cyclomer P manufactured by Daicel Chemical Industries, but are not limited thereto.

  Moreover, in the hard coat film of the present invention, it is necessary to add a photopolymerization initiator when the hard coat layer forming coating liquid is cured by ultraviolet rays. As photopolymerization initiators, acetophenones, benzophenones, α-hydroxyketone, benzylmethyl ketal, α-aminoketone, monoacylphosphine oxide, bisacylphosphine oxide, etc. may be used alone or in combination. It is preferable to use acylphosphine oxides such as monoacylphosphine oxide and bisacylphosphine oxide. By using a photopolymerization initiator of acylphosphine oxides, the internal curability can be improved even when a relatively thick hard coat layer is formed. Specifically, Irgacure 819, Darocur TPO, etc. manufactured by Ciba Specialty Chemicals are used as acylphosphine oxides. 369, Irgacure 127, etc., but are not limited thereto.

  Moreover, in the hard coat film of this invention, a solvent is contained in the coating liquid for forming a hard coat layer as necessary. At this time, as the solvent, aromatic hydrocarbons such as toluene, xylene, cyclohexane and cyclohexylbenzene, hydrocarbons such as n-hexane, dibutyl ether, dipropylene glycol monomethyl ether, dimethoxymethane, dimethoxyethane, diethoxyethane Ethers such as propylene oxide, dioxane, dioxolane, trioxane, tetrahydrofuran, anisole and phenetole, and methyl isobutyl ketone, methyl butyl ketone, acetone, methyl ethyl ketone, diethyl ketone, dipropyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, Ketones such as methylcyclohexanone and methylcyclohexanone, ethyl formate, propyl formate, n-pentyl formate, methyl acetate Esters such as ethyl acetate, methyl propionate, ethyl propionate, n-pentyl acetate, and γ-ptyrolactone, cellosolves such as methyl cellosolve, cellosolve, butyl cellosolve, cellosolve acetate, methanol, ethanol, isopropyl alcohol, etc. It is appropriately selected from among alcohols, water, etc. in consideration of appropriate coating. Moreover. It is preferable to use acetates such as methyl acetate, ethyl acetate, propyl acetate, and butyl acetate as a main component, and several types may be mixed and used as a mixed solvent. The solvent can be present in the composition in an amount of up to 95% by weight of the entire hard coat layer forming coating solution.

  In the hard coat-type coating liquid of the present invention, in addition to the above components, compatible additives as necessary, for example, plasticizers, stabilizers, surfactants, leveling agents, coupling agents, etc. Further, it can be added within a range not impairing the object of the present invention.

  A coating liquid for forming a hard coat layer containing a solvent is applied to a triacetyl cellulose base material, and then the solvent is removed by a drying step, followed by curing with ionizing radiation to form a hard coat layer. At this time, as a coating method, a coating method using a roll coater, a reverse roll coater, a gravure coater, a micro gravure coater, a knife coater, a bar coater, a die coater, or a dip coater can be used.

  As the ionizing radiation used in the curing step by ionizing radiation, ultraviolet rays and electron beams can be used. In the case of ultraviolet curing, a light source such as a high pressure mercury lamp, a low pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a carbon arc, or a xenon arc can be used. In the case of electron beam curing, electron beams emitted from various electron beam accelerators such as cockloftwald type, bandegraph type, resonant transformer type, insulated core transformer type, linear type, dynamitron type, and high frequency type can be used. . The electron beam preferably has an energy of 50 to 1000 KeV. An electron beam having an energy of 100 to 300 KeV is more preferable.

  The hard coat film of the present invention may be provided with a functional layer having antireflection performance, antistatic performance, antifouling performance, electromagnetic wave shielding performance, infrared absorption performance, ultraviolet absorption performance, color correction performance, etc., as necessary. . Examples of these functional layers include an antireflection layer, an antistatic layer, an antifouling layer, an electromagnetic wave shielding layer, an infrared absorption layer, an ultraviolet absorption layer, and a color correction layer. These functional layers may be a single layer or a plurality of layers. The functional layer may have a plurality of functions as a single layer, such as an antireflection layer having antifouling performance. Moreover, these functional layers may be provided between the triacetyl cellulose base material and the hard coat layer, or may be provided on the hard coat layer. In the present invention, a primer layer, an adhesive layer, or the like may be provided between each layer in order to improve adhesion between various layers.

  FIG. 2 shows a cross-sectional view illustrating another embodiment of the hard coat film of the present invention. In the hard coat film (1) of FIG. 2, the hard coat layer (12) is provided on the triacetyl cellulose substrate (11), and the antireflection layer (13) is further provided on the hard coat layer (12). Is provided.

  As the antireflection layer provided as a functional layer on the hard coat layer as shown in FIG. 2, the antireflection layer having a single layer structure composed of a single low refractive index layer, or a low refractive index layer and a high refractive index. Examples thereof include an antireflection layer having a laminated structure composed of a repeating structure of rate layers. In addition, as a method for forming the antireflection layer, a wet film formation method in which an antireflection layer forming coating liquid is applied to the surface of the hard coat layer and a vacuum film formation method such as a vacuum deposition method, a sputtering method, or a CVD method are used. It is divided into the method of forming by law.

  Hereinafter, a method for forming a low refractive index layer single layer by a wet film formation method by applying a coating solution for forming a low refractive index layer on the hard coat layer surface as an antireflection layer will be described. At this time, the film thickness (d) of the single layer of the low refractive index layer as the antireflection layer is the optical film thickness (nd) obtained by multiplying the film thickness (d) by the refractive index (n) of the low refractive index layer. Is designed to be equal to ¼ of the wavelength of visible light. As the low refractive index layer, a layer in which low refractive particles are dispersed in a binder matrix can be used.

  At this time, examples of the low refractive index particles include low refractive index particles made of a low refractive material such as magnesium fluoride, calcium fluoride, and porous silica. On the other hand, as the binder matrix forming material, a polyfunctional acrylate such as a polyfunctional urethane acrylate which is an ionizing radiation type material can be used. Besides these, as ionizing radiation type materials, polyether resins having an acrylate functional group, polyester resins, epoxy resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, and the like can be used. . When these ionizing radiation curable materials are used, the binder matrix is formed by irradiating ionizing radiation such as ultraviolet rays and electron beams. Moreover, metal alkoxides, such as silicon alkoxides, such as tetramethoxysilane and tetraethoxysilane, can be used as a binder matrix forming material. These can be made into an inorganic or organic-inorganic composite binder matrix by hydrolysis and dehydration condensation.

  In addition, the low refractive index layer can be formed not only by dispersing low refractive index particles in a binder matrix but also by using a fluorine-based organic material having a low refractive index without using low refractive particles. is there.

  In the case of forming a low refractive index layer, the low refractive index layer forming material is dissolved or dispersed in a solvent as necessary to form a low refractive index layer forming coating liquid, and the coating liquid is applied onto the hard coat layer. And formed by forming a coating film. At this time, if ionizing radiation curable material is used as the binder matrix forming material, the coating film is dried as necessary, and then irradiated with ionizing radiation such as ultraviolet rays and electron beams to reflect it. A prevention layer is formed. In the case of curing the coating film with ultraviolet rays, it is necessary to add a photopolymerization initiator to the coating solution for forming a low refractive index layer.When a metal alkoxide is used as a binder matrix forming material, drying, A low refractive index layer is formed by a heating process such as heating.

  FIG. 3 shows an explanatory sectional view of a transmissive liquid crystal display using the hard coat film of the present invention. The transmissive liquid crystal display of FIG. 3A includes a backlight unit (5), a polarizing plate (4), a liquid crystal cell (3), a polarizing plate (2), and a hard coat film (1) in this order. . At this time, the antiglare film (1) side becomes the observation side, that is, the display surface.

  The backlight unit (5) includes a light source and a light diffusing plate. The liquid crystal cell has a structure in which an electrode is provided on one transparent substrate, an electrode and a color filter are provided on the other transparent substrate, and liquid crystal is sealed between both electrodes. The polarizing plate provided so as to sandwich the liquid crystal cell (3) has a structure in which the polarizing layer (23, 43) is sandwiched between the triacetyl cellulose base materials (11, 21, 41, 42).

  In FIG. 3, the polarizing layer (23) is provided in the surface on the opposite side of the hard-coat layer of the triacetyl-cellulose base material (11) of a hard-coat film (1), and a triacetyl-cellulose base material (11 ) Has a structure that doubles as the base material of the hard coat film (1) and the triacetyl cellulose base material of the polarizing plate (2).

  Moreover, in the transmissive liquid crystal display of this invention, you may provide another functional member. Other functional members include, for example, a diffusion film, a prism sheet, a brightness enhancement film for effectively using light emitted from a backlight, and a phase difference film for compensating for a phase difference between a liquid crystal cell and a polarizing plate. Is mentioned.

  Hereinafter, embodiments of the present invention will be described with reference to specific examples, but the present invention is not limited to the examples described below. In addition,% of an Example and a comparative example means weight%.

<Coating liquid 1>
Cyclomer ACA-250 (polymer compound, manufactured by Daicel Chemical Industries, solid content 45%, dipropylene glycol monomethyl ether solvent, Tg: 136 ° C., trade name) 4.44 g, UA-306H (urethane acrylic oligomer, Kyoeisha Chemical Co., Ltd.) After dissolving 8.00 g of Kogyo Co., Ltd., trade name) in 12.56 g of ethyl acetate, Darocur TPO (Photoinitiator, Ciba Specialty Chemicals, trade name) 0.30 g, Irgacure 184 (Photoinitiator, Ciba Specialty Chemicals) Manufactured, trade name) 0.20 g was dissolved to obtain a coating solution 1. Cyclomer ACA-250 is a polymer compound having the structure shown in (Chemical Formula 4).

<Coating liquid 2>
Similar to <Coating liquid 1> except that UV-1700B (urethane acrylic oligomer, manufactured by Nippon Gosei Kagaku Co., Ltd., trade name) is used instead of UA-306H (urethane acrylic oligomer, manufactured by Kyoeisha Chemical Industry Co., Ltd., trade name). The coating liquid 2 was obtained.

<Coating liquid 3>
Instead of cyclomer ACA-250 (polymer compound, manufactured by Daicel Chemical Industries, solid content 45%, dipropylene glycol monomethyl ether solvent, Tg: 136 ° C., trade name), cyclomer ACA-230AA (polymer compound, Coating solution 3 was prepared in the same manner as in <Coating solution 1> except that Daicel Chemical Industries, Ltd., solid content 55%, dipropylene glycol monomethyl ether solvent, Tg: 120 ° C., trade name) was used. Cyclomer ACA-230AA is a polymer compound having the structure shown in (Chemical Formula 4).

<Coating liquid 4>
Instead of cyclomer ACA-250 (polymer compound, manufactured by Daicel Chemical Industries, solid content 45%, dipropylene glycol monomethyl ether solvent, Tg: 136 ° C., trade name), dialnal BR80 (polymer compound, Mitsubishi Rayon) A coating solution 4 was prepared in the same manner as in <Coating solution 1> except that a product obtained by dissolving Tg: 105 ° C., trade name) in a dipropylene glycol monomethyl ether solvent at a solid content of 45% was used. Incidentally, the dialnal BR80 is a polymer compound having no carbon-carbon unsaturated bond in the side chain.

<Coating fluid 5>
Instead of cyclomer ACA-250 (polymer compound, manufactured by Daicel Chemical Industries, solid content 45%, dipropylene glycol monomethyl ether solvent, Tg: 136 ° C., trade name), dialnal BR90 (polymer compound, Mitsubishi Rayon) A coating solution 5 was prepared in the same manner as in <Coating solution 1> except that Tg: 65 [deg.] C., trade name) dissolved in a dipropylene glycol monomethyl ether solvent at a solid content of 45% was used. Incidentally, the dialnal BR90 is a polymer compound having no carbon-carbon unsaturated bond in the side chain.

<Example 1-3>
On the base film, triacetylcellulose (TAC) film (Fuji Photo, TDY80UL, thickness 80 μm), <Coating liquid 1> to <Coating liquid 3> are applied as wire coat # After coating with No. 20 and drying for 1 minute with a blow dryer maintained at 100 ° C., it was cured by UV irradiation (integrated light quantity 500 mJ / cm ² ) with an electrodeless lamp (V bulb manufactured by Fusion), and triacetyl A hard coat layer was formed on a cellulose substrate to produce a hard coat film.

<Example 4-6>
On the base film, triacetylcellulose (TAC) film (Konica Minolta, KC4UYW, thickness 40 μm), <Coating liquid 1> to <Coating liquid 3> as wire coat # After coating with No. 16 and drying with a blow dryer maintained at 100 ° C. for 1 minute, it was cured by UV irradiation (integrated light amount 500 mJ / cm ² ) with an electrodeless lamp (V bulb manufactured by Fusion), and triacetyl A hard coat layer was formed on a cellulose substrate to produce a hard coat film.

<Comparative Example 1-2>
On the base film, triacetylcellulose (TAC) film (Fuji Photo, TDY80UL, thickness 80 μm), <Coating liquid 4> to <Coating liquid 5> are formed with wire bar # 20 for forming a hard coat layer. After coating and drying for 1 minute with a blast dryer maintained at 100 ° C., it is cured by UV irradiation (integrated light quantity: 500 mJ / cm ² ) with an electrodeless lamp (V bulb manufactured by Fusion), and triacetylcellulose group A hard coat layer was formed on the material to prepare a hard coat film.

About the hard coat film produced in Examples 1-6 and Comparative Examples 1 and 2, it evaluated about the method shown below. Moreover, the evaluation result of the hard coat film produced in the Example was shown in (Table 1).
Pencil hardness: Based on JIS K 5400, measured with a weight of 500 g.
Curl: One side of a sample cut to 2 × 50 mm was fixed and its radius of curvature was measured.
Thermal curl: The radius of curvature immediately after heating for 5 minutes in an oven at 75 ° C. was measured with one side of the sample cut in the same manner as curl fixed.
Adhesiveness: A grid cut (1 × 1 mm, 100 mm) was applied to the coated surface, and a peel test using a cellophane adhesive tape was performed. The numerical value is shown by the remaining amount.
Light-resistant adhesion: The peeling test was carried out after 100 hours in a fade meter.

FIG. 1 is an explanatory sectional view of a hard coat film of the present invention. FIG. 2 is an explanatory sectional view of another embodiment of the hard coat film of the present invention. FIG. 3 is an explanatory sectional view of a transmissive liquid crystal display using the hard coat film of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hard coat coat film 11 Triacetyl cellulose base material 12 Hard coat layer 13 Antireflection layer 2 Polarizing plate 21 Triacetyl cellulose base material 23 Polarizing layer 3 Liquid crystal cell 4 Polarizing plate 41 Triacetyl cellulose base material 42 Triacetyl cellulose base material 43 Polarizing layer 5 Backlight unit

Claims (9)

A hard coat film comprising a hard coat layer on at least one surface of a triacetyl cellulose substrate,
The hard coat layer is obtained by curing a polymer compound having a carbon-carbon unsaturated bond in a side chain and having a glass transition temperature of 70 ° C. or more and a polyfunctional acrylate by ionizing radiation. Features a hard coat film.   The hard coat film according to claim 1, wherein the polymer compound has an acryloyl group or a methacryloyl group in a side chain, and a saturated aliphatic ring in the side chain.   The hard coat film according to claim 1 or 2, wherein the polymer compound is contained in the hard coat layer in a range of 10 parts by weight to 40 parts by weight.   The hard coat film according to any one of claims 1 to 3, wherein the hard coat layer contains a photopolymerization initiator, and the photopolymerization initiator is acylphosphine oxide.   The hard coat film according to claim 1, wherein the polyfunctional acrylate is a polyfunctional urethane acrylate.   The hard coat film according to any one of claims 1 to 5, wherein the hard coat layer has a thickness of 5 µm or more and 15 µm or less.   The hard coat film according to any one of claims 1 to 6, wherein the hard coat film contains no filler. A hard coat film comprising a hard coat layer on at least one surface of a triacetyl cellulose substrate,
A hard coat film, wherein the hard coat layer is obtained by curing a polymer compound represented by (Chemical Formula 1) and a polyfunctional acrylate.

(Wherein R ₁ represents a methyl group or a hydrogen atom, R ₂ represents a substituent selected from an alkyl group, an aryl group, a hydroxyalkyl group, a hydrogen atom, etc., and R ₃ includes an alicyclic ring, A residue having a —C═CH ₂ group at the terminal is shown. M + n = 1.)   A liquid crystal display provided with the hard coat film of any one of Claims 1 thru | or 8.

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