JP2007246714A - Coating composition which forms finely uneven surfaces and application thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating composition which has highly large freedom on resin selection and the like, when produced, can reflect the performance of a binder resin on the performance of a film as such, and can form finely uneven surfaces, when cured. <P>SOLUTION: This coating composition forming finely uneven surfaces, when cured, comprises (a) a heat-curable or photo-curable binder and (b) fluorine-containing resin particles. And an application thereof. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a coating composition for forming fine irregularities on the surface and its application, particularly to an antiglare film.

  Liquid crystal display devices (liquid crystal displays) have advantages such as thinness, light weight, and low power consumption, and are used in various fields such as computers, word processors, televisions, mobile phones, and portable information terminal devices. In these liquid crystal display devices, an anti-glare (AG) film that roughens the surface, a low reflection (LR) film that adjusts the refractive index, and a non-reflective film (AR :) Anti Reflection). As a result, problems such as a decrease in contrast due to reflection of external light and reflection of the background reflected on the display surface are solved.

  As a method for producing an antiglare film for improving the display performance of a liquid crystal display device, in general, a method of roughening the surface by processing such as cutting, embossing molding, bonding or the like at the time of film production, or including resin particles And a method of roughening the surface of the film by providing a layer on the film. Currently, the latter method of providing a layer containing resin particles on a film is widely used.

  In the case of a method of roughening the film surface using particles, although depending on the thickness of the film, resin particles having a size of about 2.0 μm are usually mixed in the film-forming composition to roughen the surface. ing. If it does not have such a size, the particles are buried inside the film thickness of the film itself, and there is a tendency that the influence of the particle shape does not appear on the surface. However, on the other hand, when the particle size is about 2.0 μm, a clouding phenomenon called “haze” occurs, and the visibility of the image is deteriorated.

  Although it is conceivable to reduce the film thickness and the particles to be blended, reducing the film thickness causes problems in terms of toughness required for the film and weakness to scratches. In addition, the use of small particles also reduces the uneven shape formed on the surface, thus reducing the antiglare property. When the film thickness is made thin and only the particles are mixed, the film formability or the physical properties of the film are extremely lowered.

  Japanese Unexamined Patent Application Publication No. 2004-126495 (Patent Document 1) discloses a method of forming fine irregularities on the surface of a coating film by using a phase separation technique called spinodal decomposition from a liquid resin mixture. Although the decomposition phenomenon called spinodal decomposition is described in Patent Document 1, it is difficult to understand what kind of decomposition phenomenon occurs and what causes decomposition and phase separation. However, it is described that a certain type of resin undergoes phase separation in a solution in which a plurality of resins such as a resin and a curable resin precursor are dissolved. In the case of this method, the resin type to be selected is limited to those that cause spinodal decomposition, and the degree of freedom in resin selection is greatly limited. In addition, since it is not clear what causes spinodal decomposition, the resin, solvent, or other conditions must be adjusted to cause spinodal decomposition, and control of the conditions is complicated.

  In WO 2005/073763 pamphlet (patent document 2), unlike patent document 1, the concept of solubility parameter (SP) is newly introduced without using spinodal decomposition, and two kinds of resins are combined. A technique for separating and forming fine irregularities on the surface is shown. This technique is excellent because fine and random irregularities are effectively formed on the film surface without using particles. However, it is different from the present invention using specific particles.

  On the other hand, a technique of blending a fluororesin in the film is described in Japanese Patent Application Laid-Open No. 2005-300567 (Patent Document 3). This film is a low refractive index layer formed on the antiglare layer, It uses the refractive index of a fluororesin and is not an invention related to antiglare properties.

JP 2004-126495 A International Publication No. 2005/073763 Pamphlet JP-A-2005-300567

  The present invention provides a coating composition that has a very high degree of freedom in resin selection at the time of production and that forms fine irregularities on the surface during curing that can directly reflect the performance of the binder resin in the performance of the film. Let it be an issue.

  The present invention provides a coating composition that forms fine irregularities on the surface at the time of curing, including (a) a thermosetting or photocurable binder and (b) fluorine-containing resin particles, thereby achieving the above object. Is done.

  The coating composition preferably further contains a solvent (c) that dissolves the thermosetting or photocurable binder (a) and disperses or swells the fluorine-containing resin particles (b).

  The thermosetting or photocurable binder (a) may include resin particles that do not contain fluorine.

  The fluorine-containing resin particles (b) of the present invention preferably have a particle size of 0.03 to 0.5 μm.

  Further, the fluorine-containing resin particles (b) are preferably contained in an amount of 0.05 to 10.0% by weight based on the solid content of the whole composition.

  The solvent (c) is preferably an ester solvent.

  The present invention also provides an antiglare film obtained by curing the coating composition.

  The present invention further provides a method for producing an antiglare film, which includes a coating step of applying the coating composition to a transparent substrate, and a curing step of curing the obtained coating film.

  The present invention comprises (a) a coating composition comprising (b) a fluorine-containing resin particle in a thermosetting or photo-curable binder, coated on a substrate, and then cured to obtain a fluorine-containing resin particle (b The oil repellency of the binder (a) causes non-uniformity in the binder (a) resin, and also provides a method for forming fine irregularities on the coating film surface.

  The present invention further provides (a) a fluorine-containing resin by applying a coating composition in which a small amount of (b) fluorine-containing resin particles are blended in a thermosetting or photocurable binder, and then curing the coating composition on a substrate. The uneven surface of the binder (a) is caused by the oil repellency of the particles (b) to form fine irregularities on the surface of the coating film, and the performance of the coating film maintains the performance of the binder (a). A method for controlling the performance of a coating film having

  In the present invention, fine irregularities are formed on the surface of the cured coating only by blending fluorine-containing resin particles having a small particle size into a thermosetting or photocurable binder in a relatively small amount. The water and oil repellency of the fluorine-containing resin particles is considered to eliminate the resin binder and cause non-uniformity in the binder resin, thereby forming fine irregularities on the coating surface. The fluorine-containing resin particles have a smaller particle size than conventional anti-glare film particles, and may be, for example, 0.03 to 0.5 μm. Surface unevenness sufficient for antiglare property can be formed at 05 to 10.0% by weight.

  The small particle size of the fluorine-containing resin particles is advantageous for application to an antiglare film because a haze phenomenon called “haze” does not occur. In addition, the low compounding amount reflects the properties of the binder resin directly in the properties of the cured film, so the physical properties of the membrane and other necessary properties can be satisfied simply by selecting the binder resin. , Design freedom is greatly increased. Since the fluorine-containing resin particles have water / oil repellency with respect to a wide range of binder resin types, many types of binder resins can be used in this respect as well.

  Further, the coating composition of the present invention does not use a phase separation phenomenon between resins. In the method using the phase separation phenomenon between the resin and the resin, as schematically shown in FIG. 2, the mass of the resin B seems to exist in a flat island shape of about several tens of microns in the sea of the resin A. Form. On the other hand, in the present invention, as shown in FIG. 1, it is considered that small fluorine-containing resin particles are scattered in the sea of the uniform matrix layer of the binder resin. Since no defect phenomenon occurs, the physical performance of the film itself substantially matches the performance of the binder resin.

Coating Composition As described above, the coating composition of the present invention includes (a) a thermosetting or photocurable binder and (b) fluorine-containing resin particles. Moreover, the solvent (c) which melt | dissolves a thermosetting or photocurable binder (a) and disperse | distributes or swells a fluorine-containing resin particle (b) as needed is included.

Ingredient (a)
The thermosetting or photocurable binder of component (a) is a variety of thermosetting or photocurable resin binders because the fluorine-containing resin particles (b) exhibit water and oil repellency for a wide range of resins. Can be used.

  The thermosetting binder includes a resin having functional groups that are reactive with each other at an elevated temperature or a resin that reacts with a predetermined curing agent at an elevated temperature. Any resin skeleton may be used, and examples thereof include acrylic resins, olefin resins, polyether resins, polyester resins, polyurethane resins, polysiloxane resins, polysilane resins, polyimide resins, and polycarbonate resins.

  Examples of combinations of functional groups reactive with each other at elevated temperature include, for example, functional groups having active hydrogen (hydroxyl group, amino group, thiol group, carboxyl group, etc.) and epoxy groups, functional groups having active hydrogen and isocyanate groups, Ethylenically unsaturated group and ethylenically unsaturated group (polymerization of ethylenically unsaturated group occurs), silanol group and silanol group (condensation polymerization of silanol group occurs), silanol group and epoxy group, active methylene and acryloyl group, Examples thereof include an oxazoline group and a carboxyl group. By introducing these into the resin skeleton, thermal reactivity is imparted. In order to perform the reaction at an elevated temperature, the reactive group may be subjected to a treatment called an appropriate block treatment or cap treatment. For example, an isocyanate group can be regenerated at an elevated temperature by blocking the isocyanate group with a lower alcohol.

  In addition, the functional groups that react with each other include those that react with each other by mixing together a catalyst or a curing agent, if necessary. Examples of the catalyst that can be used here include a radical initiator, an acid / base catalyst, and a metal catalyst. Examples of the curing agent that can be used include a melamine curing agent, a (block) isocyanate curing agent, and an epoxy curing agent.

  The photocurable binder is a resin having a functional group that undergoes a curing reaction when irradiated with light, and is usually a combination of a photopolymerization initiator and a resin having an unsaturated double bond. Light includes ultraviolet light, visible light, infrared light, and the like. Any resin skeleton may be used, and examples thereof include acrylic resins, olefin resins, polyether resins, polyester resins, polyurethane resins, polysiloxane resins, polysilane resins, polyimide resins, and polycarbonate resins. Those having unsaturated double bonds bonded to these resin skeletons are usually used.

  Specific examples of the photopolymerization initiator include acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone, α-amyloxime ester, tetramethyl monosulfide, thioxanthone, and the like. As the photopolymerization initiator, commercially available products can be used. For example, as a photocleavable polymerization initiator, Irgacure (907, 369, 819, etc.) manufactured by Ciba Specialty Chemicals is cited as a preferred example. It is done. In addition, photosensitizers may be mixed and used, and specific examples thereof include n-butylamine, triethylamine, poly-n-butylphosphine, and the like.

  The binder (a) has a light transmittance of 85% or more, preferably 90 to 100%, and a glossiness (incident angle of 60 °) of 60% or more, preferably at the time of curing. Is preferably 65 to 100%. The light transmittance is measured with “Haze Meter” manufactured by Suga Test Instruments Co., Ltd. Glossiness is measured with Toyo Seiki Seisakusho "Gardner Micro Trigloss".

  When the light transmittance is less than 85%, the entire display element becomes dark, and when the glossiness is less than 60%, white fog occurs.

Ingredient (b)
The fluorine-containing resin particles (b) to be blended in the coating composition of the present invention are particles obtained by forming a resin containing fluorine atoms. Examples thereof include particles obtained by polymerizing a fluorine-containing acrylic monomer by emulsion polymerization. These particles are preferably non-crosslinked.

  Examples of the fluorine-containing acrylic monomer include trifluoropropyl (meth) acrylate, trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, hexafluorobutyl (meth) acrylate, and perfluorooctylethyl (meth) acrylate. .

  In addition to the fluorine-containing acrylic monomer, other polymerizable monomers may be added for copolymerization. Examples of other polymerizable monomers include olefinic monomers such as ethylene, propylene, butylene; styrene monomers such as styrene and α-methylstyrene; acrylic monomers such as (meth) acrylic acid and methyl (meth) Examples include acrylate and ethyl (meth) acrylate.

  The fluorine-containing resin particles (b) preferably have a particle size of 0.03 to 0.5 μm, more preferably 0.05 to 0.3 μm, and most preferably 0.07 to 0.15 μm. When the particle diameter exceeds 0.5 μm, although unevenness can be formed, interface scattering due to the difference in refractive index between the resin and the binder becomes significant, resulting in white haze and a decrease in light transmittance. When the particle size is smaller than 0.03 μm, it is difficult to produce and the surface irregularities tend to be too small. In the present specification, “particle diameter” or “particle diameter” means the diameter of a particle, and means an average value of the particle diameter.

  The fluorine content of the fluorine-containing resin particles (b) can also be a parameter for controlling the formation of surface irregularities. The fluorine content of the fluorine-containing resin particles (b) is preferably 5 to 60% by weight, more preferably 15 to 40% by weight, and most preferably 20 to 30% by weight based on the total weight of the fluorine-containing resin particles. is there. When the fluorine content is less than 5% by weight, unevenness formation on the surface of the cured film does not occur, and the effect of the present invention cannot be achieved. When the fluorine content is larger than 60% by weight, incompatibility with the binder becomes remarkable, and there is a tendency to cause white turbidity.

  The blending amount of the fluorine-containing resin particles (b) in the coating composition is preferably 0.05 to 10.0% by weight, more preferably 0.1 to 5.0% by weight, based on the solid content of the composition. Most preferably, it is 0.5 to 2.0% by weight. When the amount is less than 0.05% by weight, unevenness formation on the surface of the cured film does not occur, and the effect of the present invention cannot be achieved. When the blending amount of the fluorine-containing resin particles is larger than 10.0% by weight, it becomes ground glass and the haze is remarkably increased.

  In the present invention, by adjusting the fluorine content of the fluorine-containing resin particles (b) and the blending amount in the coating composition, the depth of the irregularities formed on the surface of the cured film and the number of irregularities can be easily controlled. It can be extremely important. Moreover, since the compounding quantity of the fluorine-containing resin particles (b) in the coating composition is small, the performance of the binder resin is directly reflected in the film performance, so that it becomes easy to control the performance of the cured film.

  Accordingly, in the present invention, (a) a coating composition in which (b) fluorine-containing resin particles are blended in a thermosetting or photocurable binder is applied on a substrate and then cured, whereby a coating film surface is obtained. A new method of forming fine irregularities is provided. Fine irregularities are formed on the surface of the added coating film of the fluorine-containing resin particles (b), which can be said to be a simple and simple method for forming fine irregularities.

  In the present invention, (a) a thermosetting or photocurable binder is blended with (b) fluorine-containing resin particles in a predetermined amount, and the obtained coating composition is applied on a substrate and then cured. By this, the method of controlling the number and depth of the fine unevenness | corrugation on the coating-film surface according to the compounding quantity of a fluorine-containing resin particle (b) is also provided. Since the number and depth of fine irregularities formed on the coating film surface can be controlled simply by changing the blending amount of the fluorine-containing resin particles (b), it is possible to immediately respond to each demand for anti-glare films, etc. Have

Ingredient (c)
The coating composition of the present invention usually contains a solvent (c) that dissolves the curable or photocurable binder (a) and disperses or swells the fluorine-containing resin particles (b). As the solvent (c), an organic solvent which is generally used as a solvent is used. However, the solvent (c) must dissolve the component (a) and disperse or swell the component (b) as described above. Specific examples of the solvent that can be used include aromatic solvents such as toluene and xylene; ketone solvents such as methyl ethyl ketone, acetone, methyl isobutyl ketone, and cyclohexanone; diethyl ether, isopropyl ether, tetrahydrofuran, dioxane, and ethylene glycol dimethyl ether. Ether solvents such as ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether, anisole and phenetol; ester solvents such as ethyl acetate, butyl acetate, isopropyl acetate and ethylene glycol diacetate; dimethylformamide, diethyl Amide solvents such as formamide and N-methylpyrrolidone; Bed, ethyl cellosolve, cellosolve solvents such as butyl cellosolve; methanol, ethanol, alcohol solvents such as propanol; and the like; dichloromethane, halogenated solvents such as chloroform. These solvents may be used alone or in combination of two or more. Of these solvents, ester solvents, ether solvents, and ketone solvents are preferably used, and ester solvents are particularly preferable.

Other Components The coating composition of the present invention may contain existing resin particles (excluding fluororesin particles) in addition to the components (a), (b) and (c). Suitable resin particles include acrylic and silicon. The particles may be inorganic particles such as metal oxides.

  Various additives can be added to the coating composition of the present invention as necessary. Examples of such additives include conventional additives such as antistatic agents, plasticizers, surfactants, antioxidants, and ultraviolet absorbers.

Antiglare Film The antiglare film of the present invention has a transparent substrate and an antiglare layer. This antiglare layer is formed from a coating composition that forms fine irregularities on the surface upon curing.

  Various transparent plastic films, transparent plastic plates, glass and the like can be used as the transparent substrate. Examples of transparent plastic films include triacetyl cellulose (TAC) film, polyethylene terephthalate (PET) film, diacetylene cellulose film, acetate butyrate cellulose film, polyethersulfone film, polyacrylic resin film, polyurethane resin film, polyester A film, a polycarbonate film, a polysulfone film, a polyether film, a polymethylpentene film, a polyether ketone film, a (meth) acrylonitrile film, or the like can be used. It is preferable to use triacetyl cellulose as the transparent substrate. The refractive index of triacetyl cellulose is about 1.48. Since triacetyl cellulose is widely used as a protective film for protecting the polarizing layer of the polarizing plate, an antiglare film obtained by using it as a transparent substrate can be used as it is as a protective film. In addition, although the thickness of a transparent base material can be selected timely according to a use, generally it is used at about 25-1000 micrometers.

  The antiglare layer is formed by applying the above coating composition on a transparent substrate. The application method of the coating composition can be selected as appropriate according to the coating composition and the state of the painting process. For example, the dip coating method, air knife coating method, curtain coating method, roller coating method, wire bar coating method, gravure method It can be applied by a coating method or an extrusion coating method (US Pat. No. 2,681,294).

  The thickness of the antiglare layer is not particularly limited, and can be set as appropriate in consideration of various factors. For example, the coating composition can be applied so that the dry film thickness is 0.01 to 20 μm.

  The coating film applied to the transparent substrate may be cured as it is, or the coating film may be dried before curing, and irregularities may be formed in advance before curing. When drying before hardening a coating film, it is 30-200 degreeC, More preferably, it is made to dry for 0.1 to 60 minutes, more preferably for 1 to 30 minutes at 40 to 150 degreeC, and a solvent is removed. it can. When the coating composition is photocurable, drying before curing has the advantage that the solvent in the antiglare layer can be effectively removed and irregularities of a desired size can be provided. is there.

  The antiglare layer is formed by curing the coating film obtained by applying the coating composition or the dried coating film. When the coating composition is thermosetting, it can be cured by heating at 40 to 280 ° C, more preferably at 80 to 250 ° C for 0.1 to 180 minutes, more preferably 1 to 60 minutes. . When the coating composition is photocurable, it can be cured by irradiating with a light source that emits light having a wavelength as required.

The antiglare film of the present invention preferably has a total light transmittance of 85% or more, more preferably 90% or more. In particular, since the present invention does not contain resin particles, it is possible to achieve a high total light transmittance as described above. The total light transmittance (T (%)) is calculated by the following equation by measuring the incident light intensity (T ₀ ) with respect to the antiglare film and the total transmitted light intensity (T ₁ ) transmitted through the antiglare film. A schematic illustration of the total light transmittance is shown in FIG.

  The total light transmittance can be measured using, for example, a haze meter (manufactured by Suga Test Instruments Co., Ltd.).

Antiglare and antireflection film of the polarizing plate present invention can be used in the polarizing plate of the liquid crystal display device (liquid crystal display). FIG. 4 shows a schematic cross-sectional view of a polarizing plate using the antiglare film of the present invention. A polarizing plate 10 illustrated in FIG. 4 has a configuration in which the antiglare film 1 is provided on one surface (upper surface side in FIG. 4) of a polarizing layer (polarizing element) 12.

  The polarizing layer 12 is laminated between two transparent substrates 5 and 14. A TAC film can be used as the transparent substrates 5 and 14. The polarizing layer 12 has a three-layer structure. The first layer and the third layer are made of a film obtained by adding iodine to polyvinyl alcohol (PVA), and the second layer in the middle is made of a PVA film. This antiglare film 1 has a configuration in which an antiglare layer 3 is laminated on a transparent substrate 5.

  When a TAC film is used as the transparent substrate provided on both outer sides of the polarizing layer 12, since there is no birefringence and polarization is not disturbed, polarization is disturbed even when laminated with PVA and PVA + iodine films serving as polarizing elements. Not. Therefore, a liquid crystal display device with excellent display quality can be obtained using such a polarizing plate 10.

  As the polarizing element constituting the polarizing layer 12 in the polarizing plate 10 as described above, a polyvinyl formal film, a polyvinyl acetal film, an ethylene-vinyl acetate copolymer system, a PVA film dyed with iodine or a dye and stretched. Film.

  In addition, when laminating each film which comprises the polarizing layer 12, it is good to perform a saponification process to the said transparent base material for the increase in adhesiveness and electrostatic prevention.

Liquid crystal display device The antiglare antireflection film of the present invention can be used in a liquid crystal display device (liquid crystal display). FIG. 5 is a schematic cross-sectional view of a transmissive display device using the antiglare film of the present invention.

  A liquid crystal display device 20 shown in FIG. 5 includes a polarizing plate 22 similar to the polarizing plate 10, a liquid crystal panel 24, and a polarizing plate 26 stacked in this order, and a backlight on the back side of the polarizing plate 26. This is a transparent liquid crystal display device in which 28 is arranged.

  Examples of the liquid crystal mode used in the liquid crystal panel 24 in the liquid crystal display device 20 include a twist nematic type (TN), a super twist nematic type (STN), a phase transition type (PC), and a polymer dispersion type (PDLC). It may be.

  The driving mode of the liquid crystal may be either a simple matrix type or an active matrix type. In the case of the active matrix type, a driving method such as TFT or MIM is adopted. The liquid crystal panel 24 may be either a color type or a monochrome type.

  The antiglare antireflection film of the present invention can be used for an image display device such as a plasma display panel (PDP), an electroluminescence display (ELD), and a cathode ray tube display (CRT) in addition to a liquid crystal display device. it can. When using the anti-glare film of this invention for a liquid crystal display device, it can arrange | position to the outermost surface of a display by providing an adhesion layer on the transparent base material surface in which the anti-glare layer is not provided. An antireflection treatment or the like may be further performed on the antiglare layer of the antiglare film according to the present invention.

  The following examples further illustrate the present invention, but the present invention is not limited thereto. Unless otherwise specified, “parts” and “%” are based on weight.

Production Example 1 (Production of Fluorine Fine Particles)
A 1 L round Kolben was charged with 800 parts of pure water and 8 parts of sodium dodecylbenzenesulfonate emulsifier and heated to 80 ° C. Next, 4 parts of potassium persulfate was added, 200 parts of diethyl trifluoroacrylate was added dropwise over 3 hours. After completion of the addition, the mixture was aged for about 5 hours, and then dried in a vacuum dryer, and fluorine having a particle size of 0.1 μm. System fine particles were obtained. The fluorine content of the fluorine-based fine particles was 34% by weight.

Example 1
20 parts of component (a) binder (acrylic resin oligomer, “light acrylate TMP-3EO-A” manufactured by Kyoeisha Chemical Co., Ltd.) component (b) fluorine-based fine particles of the above Production Example 1 (fluorine content 34%, average) Particle size 0.1 μm) 0.5 part, component (c) propylene glycol monomethyl ether acetate 80 parts, photoinitiator (benzyl derivative, “Irgacure-651” manufactured by Ciba Specialty Chemicals), fluorine 0.2 parts of a system surface tension adjusting agent (“Megafac F-470” manufactured by Dainippon Ink, Inc.) was added and stirred at 800 rpm for 1 hour at a temperature of 25 ° C. to obtain a coating solution.

This coating solution was applied to a polyethylene terephthalate film with a film thickness of 188 μm using a wire bar coater # 14, dried at 80 ° C. for 2 minutes, and then 1000 mJ / cm ² with a UV exposure machine (Oak). An anti-glare layer having a thickness of 3 μm was obtained by exposure.

Example 2
In Example 1, it implemented like Example 1 except having changed the fluorine-type fine particle of the component (b) into 1.0 part.

Example 3
In Example 1, it implemented like Example 1 except having changed the fluorine-type fine particle of the component (b) into 1.5 parts.

Comparative Example 1
In Example 1, it carried out like Example 1 except not adding 0 part, ie, not mix | blending, the fluorine-type fine particle of a component (b).

Table 1 summarizes the results of the total light transmittance, haze, 500 g load pencil hardness, glare, letter blur, and antiglare properties of the films having the antiglare treatment layer obtained in Evaluation Examples 1 to 3 and Comparative Example 1. Show. The total light transmittance, haze, 500 g load pencil hardness, glare, letter blur, and antiglare properties were evaluated by the following methods.

Using a total light transmittance haze meter (manufactured by Suga Test Instruments Co., Ltd.), the incident light intensity (T ₀ ) with respect to the anti-glare film and the total transmitted light intensity (T ₁ ) transmitted through the anti-glare film are measured. Was used to calculate the total light transmittance (T (%)). The reference was air.

A numerical value is obtained by setting a sample in a haze haze meter (manufactured by Suga Test Instruments Co., Ltd.). A lower numerical value indicates no haze.

Pencil hardness It evaluated according to the method of JISK-5400.

Character blur is determined on the character blur evaluation display surface by placing a film having an antiglare treatment layer obtained on a liquid crystal color filter having a resolution of 150 dpi, illuminating a backlight from the back, and displaying characters. The contour was visually evaluated according to the following criteria.
◎: Character blur is not felt ○: Character blur is slightly felt ×: Character blur is felt

Determination glare in the evaluation display surface glare is to place a film having an antiglare layer was obtained on the liquid crystal color filter having a resolution of 150 dpi, behind the irradiation with green backlight, the following visually Evaluation was based on criteria.
◎: No glare ○: Slight glare is felt ×: Glare is present

Evaluation of anti-glare property The anti-glare property was evaluated by copying a bare fluorescent lamp without a louver onto a film having an anti-glare layer, and visually evaluating the glare of the regular reflection light according to the following criteria.
A: Dazzle is not felt B: Slight dazzle is felt B: Dazzle is felt

  The correlation between the hazes of Examples 1 to 3 and Comparative Example 1 and the blending amount of the fluorine-based fine particles is shown in a graph as shown in FIG. As apparent from FIG. 6, the haze and the blending amount of the fluorine-based fine particles are in a substantially linear relationship.

Example 4
Component (a) Binder (epoxy skeleton oligomer, “KAYARAD TCR-1310H” manufactured by Nippon Kayaku Co., Ltd., trisphenolmethane type epoxy acrylate, 65% non-volatile content) 30.8 parts of component (b) of Production Example 1 above Fluorine-based fine particles (fluorine content 34%, average particle size 0.1 μm) 0.5 part, component (c) propylene glycol monomethyl ether acetate 69.2 parts, photoinitiator (benzyl derivative, Ciba Specialty Chemicals) "UVI-6974") 0.4 parts, fluorine surface tension regulator (Dainippon Ink Co., Ltd. "Megafac F-470") 0.2 parts was added and stirred at 800 rpm for 1 hour at 25 ° C with a disper. Thus, a coating solution was obtained.

This coating solution was applied to a polyethylene terephthalate film with a film thickness of 188 μm using a wire bar coater # 14, dried at 80 ° C. for 2 minutes, and then 1000 mJ / cm ² with a UV exposure machine (Oak). An anti-glare layer having a thickness of 3 μm was obtained by exposure.

Example 5
In Example 4, it implemented like Example 4 except having changed the fluorine-type fine particle of the component (b) into 1.0 part.

  The film having the antiglare treatment layer obtained in Examples 4 and 5 was measured for the total light transmittance, haze, 500 g load pencil hardness, glare, letter blur, and antiglare property in the same manner as in Example 1, and the results are shown in Table 1. It is shown in 2.

Comparative Example 2
Example 1 was the same as Example 1 except that the fluorine-based fine particles of component (b) were changed to 0.5 parts of acrylic resin particles (“MG-151” commercially available from Nippon Paint Co., Ltd., particle size 0.1 μm). Implemented.

Comparative Example 3
Example 1 was the same as Example 1 except that the fluorine-based fine particles of component (b) were changed to 1.0 part of acrylic resin particles (“MG-151” commercially available from Nippon Paint Co., Ltd., particle size 0.1 μm). Implemented.

  The total light transmittance, haze, 500 g load pencil hardness, glare, letter blur, and antiglare properties of the films having the antiglare treatment layers obtained in Comparative Examples 2 and 3 were measured in the same manner as in Example 1, and the results are shown. 3 shows.

  In Examples 4 and 5, it is understood that fine irregularities are formed on the surface even when the binder resin is changed from an acrylic resin to an epoxy resin. Further, in Comparative Examples 2 and 3, when the fluorine resin fine particles are changed to acrylic resin fine particles, fine irregularities are not formed on the surface, and the antiglare property cannot be obtained.

  The present invention is effective as a method for easily producing an antiglare film having antiglare properties while maintaining high light transmittance. Further, by arbitrarily changing the addition amount of fluorine-based fine particles and the fluorine content, the present invention can be applied not only to the antiglare film but also to applications requiring various uneven surfaces.

It is a schematic cross section of the anti-glare film of this invention. It is a schematic cross section of the anti-glare film by the conventional phase separation. It is a schematic explanatory drawing of a total light transmittance. It is a cross-sectional schematic diagram of the polarizing plate using the anti-glare film of this invention. 1 is a schematic cross-sectional view of a transmissive display device using the antiglare film of the present invention. It is a graph showing the correlation with Examples 1-3 and the comparative example 1 haze and the compounding quantity of fluorine-type microparticles | fine-particles.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Anti-glare film, 3 ... Anti-glare layer, 5 ... Transparent base material, 10 ... Polarizing plate, 12 ... Polarizing layer, 14 ... Transparent base material, 20 ... Liquid crystal display device, 22 ... Polarizing plate, 24 ... Liquid crystal panel, 26: Polarizing plate, 28: Backlight.

Claims (10)

  A coating composition comprising fine irregularities on the surface upon curing, comprising (a) a thermosetting or photocurable binder and (b) fluorine-containing resin particles.   The coating composition according to claim 1, further comprising a solvent (c) for dissolving the thermosetting or photocurable binder (a) and dispersing or swelling the fluorine-containing resin particles (b).   The coating composition according to claim 1, wherein the thermosetting or photocurable binder (a) includes resin particles not containing fluorine.   The coating composition according to claim 1, wherein the fluorine-containing resin particles (b) have a particle size of 0.03 to 0.5 μm.   The coating composition according to claim 1, wherein the fluorine-containing resin particles (b) are contained in an amount of 0.05 to 10.0% by weight based on the solid content of the whole composition.   The coating composition according to claim 1, wherein the solvent (c) is an ester solvent.   The anti-glare film obtained by hardening | curing the coating composition in any one of Claims 1-6. An application step of applying the coating composition according to any one of claims 1 to 6 to a transparent substrate, and a curing step of curing the obtained coating film,
A method for producing an antiglare film.   (A) A method of forming fine irregularities on a coating film surface by applying a coating composition in which (b) fluorine-containing resin particles are blended in a thermosetting or photocurable binder and then curing the coating composition on a substrate. . (A) Fluorine-containing resin particles by blending (b) fluorine-containing resin particles in a predetermined amount in a thermosetting or photo-curable binder, and applying the resulting coating composition on a substrate and then curing. A method of controlling the number and depth of fine irregularities on the coating film surface in accordance with the blending amount of (b).

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