JP2007286226A - Anti-glare member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anti-glare member capable of suppressing the degradation of contrast to the utmost, while maintaining a sufficient antireflection function and further minimizing the degradation of the contrast from an oblique direction of a display surface, when being attached to a plasma display panel. <P>SOLUTION: In an anti-glare film, an anti-glare layer 4 comprising porous silica particles 3, which have average particle size of 3.1 μm to 8.0 μm and average pore size of 7.0 nm to 24.0 nm; and a transparent layer 2, made of an ultraviolet curable resin for embedding the porous silica particles 3, such that the neighborhood of the apexes is exposed, is disposed on a transparent resin film 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an antiglare member, and more particularly, an antiglare member capable of suppressing a decrease in contrast as much as possible while maintaining a sufficient antireflection function by being attached to a display surface of a plasma display panel. It is about.

As flat panel displays (FPDs) such as plasma display panels (PDPs) increase in size and increase in image quality, the protective film and hard coat film used on the display surface of the image display section also increase in size and image quality. A prompt response to is required.
For example, in a transmissive display device such as a plasma display panel (PDP), the image quality and visibility on the display surface of the image display unit are not only the characteristics of the display device body but also the hard coat film formed on the display surface of the display device. It changes greatly by etc.

Also, as display devices such as plasma display panels (PDPs) become larger and larger, external light such as fluorescent lamps enters the display surface of the image display unit from the outside, and this light is reflected, so-called The phenomenon of reflection of external light has become a problem. This phenomenon of reflection is a serious problem particularly in a large plasma display panel (PDP) because it hinders the visibility of an image.
Therefore, an antiglare film is formed on the display surface of an image display unit of a plasma display panel (PDP) to reduce reflection and improve visibility.
As the antiglare film, a multilayer film in which metal oxide layers having different refractive indexes are stacked is used (see Patent Documents 1 and 2).
JP 2000-47004 A JP 2003-4904 A

By the way, since the conventional anti-glare film using a multilayer film has a structure in which metal oxide layers having different refractive indexes are laminated, the number of metal oxide layers is sufficient to ensure sufficient anti-glare properties. Therefore, there is a problem that it is difficult to achieve both high film strength and high antireflection performance.
In addition, since the number of metal oxide layers is increased, there is a problem in that the number of processes on the production line is increased and the cost is increased.

  The present invention has been made in order to solve the above-described problems, and can maintain a sufficient antireflection function while suppressing a decrease in contrast as much as possible. Further, the present invention is attached to a plasma display panel. In this case, an object is to provide an antiglare member capable of reducing a decrease in contrast from an oblique direction of a display surface.

  As a result of intensive studies on the antiglare member for adhering to the display surface of the plasma display panel, the present inventors have found that the average particle diameter is 3.1 μm or more and 8 or more on a film-like or sheet-like transparent substrate. A structure provided with an antiglare layer having porous silica particles having an average pore diameter of 7.0 nm or less and 7.0 nm or more and 24.0 nm or less and a transparent layer made of an ultraviolet curable resin for embedding the porous silica particles. In this case, it is possible to suppress the decrease in contrast as much as possible while maintaining a sufficient anti-reflection function. Further, when it is attached to the plasma display panel, the decrease in contrast from the oblique direction of the display surface is reduced. As a result, the present invention has been completed.

  That is, the antiglare member of the present invention is an antiglare member for adhering to the display surface of a plasma display panel, and has an average particle size of 3.1 μm or more on a film-like or sheet-like transparent substrate. And a transparent layer made of porous silica particles having an average pore diameter of 7.0 nm or more and 24.0 nm or less and an ultraviolet curable resin for embedding the porous silica particles so that a part of the porous silica particles is exposed. An anti-glare layer containing is provided.

The porous silica particles are preferably added in an amount of 1% by weight to 2% by weight with respect to the ultraviolet curable resin.
The thickness of the transparent layer is preferably 50% or more and 90% or less of the average particle diameter of the porous silica particles.
A low refractive index layer having a refractive index lower than that of the antiglare layer may be formed on the antiglare layer.

The antiglare member of the present invention preferably has a haze value of 5% or more and 15% or less.
The 60 ° gloss is preferably 45 or less.
Moreover, it is preferable that the contrast in the direction inclined by 70 ° with respect to the vertical direction of the antiglare layer is 40% or more and 80% or less.

  According to the antiglare member of the present invention, an average particle diameter of 3.1 μm or more and 8.0 μm or less, an average pore diameter of 7.0 nm or more and 24.0 nm or less on a film-like or sheet-like transparent substrate. Since an anti-glare layer comprising a porous silica particle and a transparent layer made of an ultraviolet curable resin for embedding the porous silica particle so as to partially expose the porous silica particle is provided, the porous silica particle and the transparent layer By forming nanometer-scale fine irregularities on the surface of the antiglare layer, reflection of external light can be reduced. Therefore, it is possible to suppress a decrease in contrast while maintaining a sufficient antireflection function, and as a result, it is possible to improve the visibility on the display surface of the plasma display panel.

The best mode for carrying out the antiglare member of the present invention will be described.
This embodiment is specifically described for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified.

FIG. 1 is a cross-sectional view showing an antiglare film (antiglare member) according to an embodiment of the present invention, which reduces reflection of external light by sticking to a display surface of a plasma display panel. is there.
In the figure, 1 is a transparent resin film (film-like transparent substrate), 2 is a transparent layer made of an ultraviolet curable resin formed on the resin film, and 3 is embedded in the transparent layer 2 so that the vicinity of the top is exposed. The antiglare layer 4 is composed of the transparent layer 2 and the porous silica particles 3.

The resin film 1 is preferably a transparent film having sufficient mechanical strength and physical strength and an average refractive index of 1.55 or more, and an average refractive index of 1.60 or more and 1.70 or less. Is more preferable.
Examples of such films include polyester films such as polyethylene terephthalate (PET), cellulose films such as triacetyl cellulose (TAC), polyolefin films such as polyethylene, acrylic films such as polyacrylate, polycarbonate (PC) films, poly An ether sulfone (PES) film etc. are mentioned.
In particular, in view of long-term stability and reliability, a polyethylene terephthalate (PET) film that has film strength and is widely used for optical applications is suitable.

Although the thickness of the resin film 1 is not specifically limited, Usually, it is suitably selected from the thickness of about 38 micrometers-188 micrometers.
If a resin film having a thickness within the above range is used, it is difficult to cause wrinkles and the like when it is attached to the display surface of the plasma display panel, and it does not extend more than necessary, and there is no problem such as breakage.

The average particle size of the porous silica particles 3 is preferably 3.1 μm or more and 8.0 μm or less, more preferably 3.1 μm or more and 7.0 μm or less, and further preferably 3.2 μm or more and 6.0 μm or less. .
Here, the reason why the average particle size of the porous silica particles 3 is limited to 3.1 μm or more and 8.0 μm or less is that the unevenness for obtaining the antiglare property is sufficiently formed when the average particle size is less than 3.1 μm. On the other hand, if the average particle size exceeds 8.0 μm, the unevenness becomes rough and the haze increases.

The average pore diameter of the porous silica particles 3 is preferably 7.0 nm or more and 24.0 nm or less, more preferably 10 nm or more and 22 nm or less, and further preferably 12 nm or more and 21 nm or less.
Here, the reason why the average pore diameter of the porous silica particles 3 is limited to 7.0 nm or more and 24.0 nm or less is that when the average pore diameter is less than 7.0 nm, the haze becomes low and glare occurs. On the other hand, if the average pore diameter exceeds 24.0 nm, the amount of voids in the pores increases and the haze becomes too high.

The porous silica particles 3 are preferably added in an amount of 1% by weight or more and 2% by weight or less, more preferably 1.2% by weight or more and 1.8% by weight or less, based on the ultraviolet curable resin described later. It is.
Here, the reason why the addition amount of the porous silica particles 3 is limited to 1% by weight or more and 2% by weight or less with respect to the ultraviolet curable resin is that sufficient unevenness cannot be formed if the addition amount is less than 1% by weight. On the other hand, if the addition amount exceeds 2% by weight, the unevenness increases, and the sharpness when viewed from an oblique direction is lowered.

Although it does not specifically limit as ultraviolet curable resin which comprises the transparent layer 2, For example, an epoxy acrylate resin, a urethane (meth) acrylate resin, a polyester (meth) acrylate resin etc. are used suitably.
The thickness of the transparent layer 2 is preferably 50% or more and 90% or less of the average particle diameter of the porous silica particles 3, and more preferably 55% or more and 80% or less of the average particle diameter.

  Here, the reason for limiting the thickness of the transparent layer 2 to 50% or more and 90% or less of the average particle diameter of the porous silica particles 3 is that the porous silica particles cannot be retained if the average particle diameter is less than 50%. This is because it causes dropout and damage, and on the other hand, if it exceeds 90% of the average particle diameter, the amount of protrusion of the porous silica particles becomes small.

The haze value (cloudiness value) of the antiglare film is preferably 5% or more and 15% or less, more preferably 7% or more and 14% or less.
Here, the reason why the haze value is limited to 5% or more and 15% or less is that the lower the haze value, the better the light transmission and the prevention of the decrease in contrast, but the haze value is less than 5%. This is because glare called scintillation may occur, whereas when the haze value exceeds 15%, the contrast is significantly reduced.

The antiglare film has a 60 ° gloss of preferably 45 or less, more preferably 40 or less.
Here, the reason why the 60 ° gloss is limited to 45 or less is that when the 60 ° gloss exceeds 45, reflection of external light such as a fluorescent lamp becomes intense.

The contrast in the direction inclined by 70 ° with respect to the vertical direction of the antiglare layer 4 of the antiglare film is preferably 40% or more and 80% or less, more preferably 50% or more and 80% or less.
Here, the reason why the above contrast is limited to 40% or more and 80% or less is that when the contrast is less than 40%, the visibility from an oblique direction is remarkably deteriorated, while the contrast exceeds 80%. This is because it is difficult to obtain a sufficient antiglare property.

The contrast of the antiglare film can be determined as follows.
(1) Place a 400 dpi ladder pattern on the backlight.
On the other hand, an antiglare film is attached to a soda glass plate having a thickness of 2 mm to produce a sample.
(2) With no sample placed on the ladder pattern, the camera is mounted in a direction inclined by 70 ° with respect to the vertical direction of the ladder pattern, and the maximum luminance (M _ref ) and minimum luminance (m _ref ) when there is no sample. ).
(3) A sample is placed on the ladder pattern, a camera is attached in a direction inclined by 70 ° with respect to the vertical direction of the sample, and the maximum luminance (M _s ) and the minimum luminance (m _s ) when the sample is present are measured. .

(4) Using the following equation, the contrast C _ref when there is no sample and the contrast C _s when there is a sample are obtained, and the contrast C of the sample is obtained from these contrasts C _ref and C _s .
C _ref = (M _ref −m _ref ) / (M _ref + m _ref )
C _s = (M _s −m _s ) / (M _s + m _s )
C = C _s / C _ref × 100

This antiglare film can be produced as follows.
First, porous silica particles and an ultraviolet curable resin are dissolved and dispersed in an organic solvent to produce a coating for forming an antiglare layer.
Examples of the organic solvent include, but are not limited to, alcohols such as methanol, ethanol, 2-propanol, n-butanol and 2-butanol, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, β- Oxyethyl methyl ether (methyl cellosolve), β-oxyethyl ether (ethyl cellosolve), butyl-β-oxyethyl ether (butyl cellosolve), ethylene glycol monoethers (cellosolves) such as propylene glycol monomethyl ether, benzene, toluene An aromatic hydrocarbon such as xylene is preferably used.

  Next, a coating for forming an antiglare layer on the resin film 1 is applied to the wire bar method, spin coating method, spray coating method, dipping method, gravure coating method, roll coating method, screen printing method, knife coater method, reverse roll coater method, An antiglare layer 4 is formed by applying a kiss coater method or the like to form a coating film, and then irradiating the coating film with ultraviolet rays (UV) to cure the ultraviolet curable resin.

  FIG. 2 is a cross-sectional view showing an antiglare film with an antireflection film according to an embodiment of the present invention. The difference from the antiglare film in FIG. The low refractive index layer 11 having a refractive index lower than that of the glare layer 4 is formed, and this low refractive index layer 11 is used as an antireflection film.

The refractive index of the low refractive index layer 11 is preferably 1.35 to 1.45.
The low refractive index layer 11 is not particularly limited as long as it has a function as a binder bonded to the antiglare layer 4 and is transparent, and examples thereof include polysiloxane and organosiloxane. And acrylic resins.
The low refractive index layer 11 preferably contains one or more of a fluoroalkylsilane derivative, hollow silica, and porous silica particles.

  According to the antiglare film of this embodiment, porous silica particles having an average particle diameter of 3.1 μm or more and 8.0 μm or less and an average pore diameter of 7.0 nm or more and 24.0 nm or less on the transparent resin film 1. 3 and an antiglare layer 4 composed of a transparent layer 2 made of an ultraviolet curable resin for embedding the porous silica particles 3 so that the vicinity of the top of the silica particles 3 is exposed. Can be reduced. Therefore, it is possible to suppress a decrease in contrast while maintaining a sufficient antireflection function.

Therefore, by sticking this anti-glare film on the display surface of the plasma display panel, reflection of external light such as a fluorescent lamp on the display surface can be reduced. As a result, visual recognition on the display surface of the plasma display panel can be reduced. Can be improved.
Furthermore, the antireflection function can be further improved by forming the low refractive index layer 11 on the antiglare layer 4.

Although this invention is demonstrated by Examples 1-3 and Comparative Examples 1-7, this invention is not limited to the following Example.
(Example 1)
A. Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 907 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, porous silica particles Porous beads having a particle size of 3.2 μm and an average pore size of 21 nm Cylysia 320 (trade name: manufactured by Fuji Silysia Chemical Co., Ltd.) 0.30 g, Dispersbyk-2000 (trade name: Big Chemie Japan Co., Ltd.) as a dispersant (Product) 0.1 g and 66.6 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare antiglare layer-forming coating material A1.

B. Preparation of paint for forming low refractive index layer Tetramethoxysilane TSL8114 (trade name: manufactured by GE Toshiba Silicone) 2.43 g, fluoroalkylsilane TSL8257 (trade name: manufactured by GE Toshiba Silicone) 0.70 g, methacryl group-containing silane cup Ring agent TSL8370 (trade name: manufactured by GE Toshiba Silicone) 0.20 g, hollow silica fine particle 2-propanol dispersion (catalyst chemicals) having a hollow silica fine particle content of 20% by weight, reactive silicone oil BYK-UV3500 (trade name: manufactured by Big Chemie Japan Co., Ltd.) 0.06 g and Arcosol P-9 (manufactured by Gansu Chemical Industry Co., Ltd.) 84.51 g were mixed, and dilute nitric acid was added dropwise with stirring. As the diluted nitric acid, 0.10 g of 1 mol / L nitric acid diluted with 6.0 g of pure water was used.
After dropping, the mixture was stirred as it was for 12 hours to prepare a coating B1 for forming a low refractive index layer.

C. Preparation of anti-glare film with antireflection film On a transparent polyethylene terephthalate (PET) film A-4300 (manufactured by Toyobo Co., Ltd.) with a film thickness of 75 μm, an anti-glare layer-forming coating material A1 is applied with wire bar # 3. After drying at 120 ° C. for 1 minute, the film was cured by irradiation with ultraviolet rays to produce an antiglare layer. Thereafter, a coating B1 for forming a low refractive index layer is applied on the antiglare layer with a wire bar # 5 and dried at 120 ° C. for 1 minute to produce an antiglare film with an antireflection film of Example 1. did.

(Example 2)
Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 184 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, porous silica particles Porous beads having a particle size of 3.2 μm and an average pore size of 21 nm Cylysia 320 (trade name: manufactured by Fuji Silysia Chemical Co., Ltd.) 0.60 g, Dispersbyk-2000 (trade name: Big Chemie Japan Co., Ltd.) as a dispersant (Product) 0.1 g and 66.3 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare antiglare layer-forming coating material A2.
Thereafter, an antiglare film with an antireflection film of Example 2 was produced in the same manner as in Example 1.

(Example 3)
Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 907 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, porous silica particles Porous beads having a particle size of 8.0 μm and an average pore size of 17 nm Cylicia 450 (trade name: manufactured by Fuji Silysia Chemical Co., Ltd.) 0.50 g, Dispersbyk-2000 (trade name: Big Chemie Japan Co., Ltd.) as a dispersant. (Product) 0.1 g and 66.4 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare antiglare layer-forming coating material A3.
Thereafter, an antiglare film with an antireflection film of Example 3 was produced in the same manner as in Example 1.

(Comparative Example 1)
Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 907 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, porous silica particles Porous beads having a particle size of 2.7 μm and an average pore size of 7.0 nm Cylicia 530 (trade name: manufactured by Fuji Silysia Chemical Co., Ltd.) 0.50 g, Dispersbyk-2000 (trade name: Big Chemie) as a dispersant (Japan Co., Ltd.) 0.1 g, and 66.4 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare antiglare layer-forming coating material A4.
Thereafter, an antiglare film with an antireflection film of Comparative Example 1 was produced in the same manner as in Example 1.

(Comparative Example 2)
Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 907 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, porous silica particles Porous beads having a particle size of 9.0 μm and an average pore size of 21 nm Silicia 380 (trade name: manufactured by Fuji Silysia Chemical Co., Ltd.) 0.50 g, Dispersbyk-2000 (trade name: Big Chemie Japan Co., Ltd.) as a dispersant. (Product) 0.1 g and 66.4 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare antiglare layer-forming coating material A5.
Thereafter, an antiglare film with an antireflection film of Comparative Example 2 was produced in the same manner as in Example 1.

(Comparative Example 3)
Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 907 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, porous silica particles As a dispersant, 0.50 g of porous beads Sun Festa H-52 (trade name: manufactured by Asahi Glass Co., Ltd.) and Dispersbyk-2000 (trade name: manufactured by Big Chemie Japan Co., Ltd.) ) 0.1 g and 66.4 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare antiglare layer-forming coating material A6.
Thereafter, an antiglare film with an antireflection film of Comparative Example 3 was produced in the same manner as in Example 1.

(Comparative Example 4)
Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 907 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, nonporous silica Non-porous beads with a particle size of 4 μm as a particle Quartron SP-4B (trade name: manufactured by Fuso Chemical Industries Co., Ltd.) 0.50 g, Dispersbyk-2000 (trade name: manufactured by Big Chemie Japan Co.) as a dispersant 1 g and 66.4 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare antiglare layer-forming coating material A7.
Thereafter, an antiglare film with an antireflection film of Comparative Example 4 was produced in the same manner as in Example 1.

(Comparative Example 5)
A. Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 907 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, porous silica particles Porous beads having a particle size of 3.2 μm and an average pore size of 21 nm Cylysia 320 (trade name: manufactured by Fuji Silysia Chemical Co., Ltd.) 0.30 g, Dispersbyk-2000 (trade name: Big Chemie Japan Co., Ltd.) as a dispersant. (Product) 0.1 g and 66.6 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare antiglare layer-forming coating material A8.

B. Preparation of antiglare film with antireflection function On a transparent polyethylene terephthalate (PET) film A-4300 (manufactured by Toyobo Co., Ltd.) having a film thickness of 75 μm, an antiglare layer-forming coating material A8 is applied with wire bar # 9. After drying at 120 ° C. for 1 minute, the film was cured by irradiation with ultraviolet rays to produce an antiglare layer. Thereafter, on this antiglare layer, the low refractive index layer-forming coating material B1 of Example 1 was applied with a wire bar # 5 and dried at 120 ° C. for 1 minute. A dazzling film was prepared.

(Comparative Example 6)
Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 907 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, porous silica particles Porous beads having a particle size of 4.1 μm and an average pore size of 17 nm Cylicia 430 (trade name: manufactured by Fuji Silysia Chemical Co., Ltd.) 0.2 g, Dispersbyk-2000 (trade name: BYK Chemie Japan Co., Ltd.) as a dispersant. (Product) 0.1 g and 66.6 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare antiglare layer-forming coating material A9.
Thereafter, an antiglare film with an antireflection film of Comparative Example 6 was produced in the same manner as in Example 1.

(Comparative Example 7)
Preparation of antiglare layer-forming coating material 30.0 g of dipentaerythritol hexaacrylate (DPHA), 3.0 g of Irgacure 907 (trade name: Ciba Specialty Chemicals Co., Ltd.) as a photoinitiator, porous silica particles 1.0 g of porous beads having a particle size of 4.1 μm and an average pore size of 17 nm Cylicia 430 (trade name: manufactured by Fuji Silysia Chemical Co., Ltd.), Dispersbyk-2000 (trade name: Big Chemie Japan Co., Ltd.) as a dispersant (Product) 0.1 g and 66.6 g of toluene as a solid content adjusting solvent were mixed and dispersed using a high-speed mixer to prepare anti-glare layer-forming coating material A10.
Thereafter, an antiglare film with an antireflection film of Comparative Example 7 was produced in the same manner as in Example 1.

"Evaluation"
The total light transmittance, haze value (cloudiness value), gloss at 60 °, visibility reflectance, and adhesion of each of the antiglare films with antireflection films of Examples 1 to 3 and Comparative Examples 1 to 7 obtained as described above. Evaluation items for pencil hardness, steel wool resistance, and visibility from an oblique direction were evaluated using the following methods.

(1) Total light transmittance The total light transmittance of the anti-glare film with an antireflection film was measured in accordance with Japanese Industrial Standard JIS K 7105 "Testing method for optical properties of plastics".
(2) Haze value The haze value of an antiglare film with an antireflection film was measured according to Japanese Industrial Standard JIS K 7105 "Testing method for optical properties of plastics".
(3) Gloss at 60 ° The gloss at 60 ° of an antiglare film with an antireflection film was measured according to Japanese Industrial Standard JIS K 7105 “Testing method for optical properties of plastic”.

(4) Visibility reflectance Using a UV / visible spectrophotometer V-570 (manufactured by JASCO Corp.), the 5 ° specular reflectance of the antiglare film with an antireflection film was measured, and this was compared with the measured value. The visibility reflectance of the antiglare film with an antireflection film was calculated by multiplying the sensitivity value.
(5) Adhesion Each side of 10 mm square on the surface of an antiglare film with an antireflection film in accordance with the operation of the cross-cut peeling method of Japanese Industrial Standard JIS K 5600-5-6 “Paint General Test Method” A total of 100 squares are formed by cutting 11 mm incisions at 1 mm intervals with a cutter knife, and a cellophane tape having a width of 24 mm is closely attached to the cell, and this cellophane tape is quickly put in the direction of 60 degrees. Forced peeling. This cellophane tape adhesion and peeling operation was repeated three times, and the number of remaining squares was counted.

(6) Pencil hardness The pencil hardness of the antiglare film with an antireflection film was measured in accordance with Japanese Industrial Standard JIS K 5600-5-4 “Paint General Test Method”.
(7) Anti-steel wool properties While applying a load of 250 g / cm ² to steel wool of # 0000, it was reciprocated 10 times on the surface of the low refractive index layer of the antiglare film with antireflection film, and then low refraction The surface of the rate layer was observed and evaluated. The evaluation criteria are as follows.
○: No scratch is observed in the low refractive index layer.
X: Scratches are observed in the low refractive index layer.

(8) Visibility from an oblique direction When the contrast C of the antiglare film is determined by the above-described method, and the value of the contrast C is 40% or more and 80% or less, it is determined that the visibility is “◯”. When the value of the contrast C is out of the above range, it is determined that the visibility is “x”.
Table 1 shows the evaluation results of the antiglare films with antireflection films of Examples 1 to 3 and Comparative Examples 1 to 7.

  The antiglare member of the present invention is a porous material having an average particle diameter of 3.1 μm or more and 8.0 μm or less and an average pore diameter of 7.0 nm or more and 24.0 nm or less on a film-like or sheet-like transparent substrate. The plasma display panel (PDP) is provided with an antiglare layer including silica particles and a transparent layer made of an ultraviolet curable resin for embedding the porous silica particles so that a part of the silica particles is exposed. Needless to say, the present invention can be applied to the display surface of the image display unit of other self-luminous display devices, and its industrial value is extremely large.

It is sectional drawing which shows the anti-glare film of one Embodiment of this invention. It is sectional drawing which shows the anti-glare film with an antireflection film of one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent resin film 2 Transparent layer 3 Porous silica particle 4 Anti-glare layer 11 Low refractive index layer

Claims (7)

An anti-glare member for adhering to the display surface of a plasma display panel,
A porous silica particle having an average particle diameter of 3.1 μm or more and 8.0 μm or less, an average pore diameter of 7.0 nm or more and 24.0 nm or less on a film-like or sheet-like transparent substrate; An anti-glare member comprising an anti-glare layer including a transparent layer made of an ultraviolet curable resin for embedding particles so that a part of the particles is exposed.   2. The antiglare member according to claim 1, wherein the porous silica particles are added in an amount of 1% by weight to 2% by weight with respect to the ultraviolet curable resin.   The antiglare member according to claim 1 or 2, wherein a thickness of the transparent layer is 50% or more and 90% or less of an average particle diameter of the porous silica particles.   4. The antiglare member according to claim 1, wherein a low refractive index layer having a refractive index lower than that of the antiglare layer is formed on the antiglare layer.   The antiglare member according to any one of claims 1 to 4, wherein the haze value is 5% or more and 15% or less.   The antiglare member according to any one of claims 1 to 5, wherein the 60 ° gloss is 45 or less.   The antiglare member according to any one of claims 1 to 6, wherein a contrast in a direction inclined by 70 ° with respect to a vertical direction of the antiglare layer is 40% or more and 80% or less.

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