WO2010087122A1 - Film for optical filter and optical filter comprising same for plasma display panel - Google Patents

Abstract

A film for optical filters that has excellent light resistance and an optical filter for plasma display panels that comprises the film are developed using a pressure-sensitive adhesive comprising a crosslinkable acrylic resin, a crosslinking agent, and a dye absorbing neon light. Use is made of a pressure-sensitive adhesive comprising a crosslinkable acrylic resin and a crosslinking agent, the resin being obtained by copolymerizing 70.1-99.8 wt.% alkyl (meth)acrylate in which the alkyl group has 4-12 carbon atoms, 0.1-10 wt.% hydroxylated monomer copolymerizable with the alkyl (meth)acrylate, and 0.1-19.9 wt.% other monomer copolymerizable with both the alkyl (meth)acrylate and the hydroxylated monomer.  A dye absorbing neon light is highly stable in a layer of the pressure-sensitive adhesive.  By forming the pressure-sensitive adhesive layer on one side of a transparent substrate, a film for optical filters that has excellent light resistance and an optical filter for plasma display panels that comprises the film have been developed.

Description

Optical filter film and optical filter for plasma display panel using the same

The present invention relates to an optical filter film excellent in durability, in which a neon light absorbing dye is contained in an adhesive layer, and an optical filter for a plasma display panel (hereinafter referred to as PDP) using the same.

The principle of PDP is that a light is applied to the cell wall by applying a voltage to a rare gas (neon, xenon, etc.) enclosed in a cell sandwiched between two sheet-like glasses, and emitting ultraviolet light emitted from the rare gas in a plasma state. , Which generates visible light necessary for video, but at the same time as visible light, orange light near the wavelength of 595 nm, which reduces the color purity of red light due to near infrared rays, electromagnetic waves harmful to the human body, and neon gas. Since harmful electromagnetic waves such as neon light (hereinafter referred to as neon light) are also emitted, it transmits useful visible light, but it is necessary to shield near infrared rays including neon light and electromagnetic waves harmful to the human body. Therefore, an optical filter for that purpose is required. (See Patent Document 1)

By using a multilayer sputtered film made of a metal material as a member used for the optical filter, it is possible to simultaneously cut near infrared rays and electromagnetic waves harmful to the human body. (See Patent Documents 2 and 3)
However, for neon light, it is necessary to provide a separate shielding layer. Conventionally, a neon light absorbing film in which a specific dye that absorbs neon light is added to a binder resin and applied to a transparent substrate, and a near infrared ray and electromagnetic wave shielding function An optical filter in which a base material having antiglare, an antiglare and antireflection film and the like are bonded together with an adhesive is used. As the dye, a cyanine dye having sufficient absorption characteristics with a small amount of addition was mainly used.

If the neon light-absorbing dye can be contained in the pressure-sensitive adhesive layer, neon light absorbing ability can be imparted between any layers constituting the optical filter, so that it can be expected that the efficiency of manufacturing the optical filter is remarkably improved. However, when neon light-absorbing dyes typified by cyanine dyes are added to the pressure-sensitive adhesive, the dyes deteriorate after the durability test, unlike additions to binder resins for coatings made of polymers such as polyester resins and acrylic resins. There is a problem peculiar to pressure-sensitive adhesives that the neon light absorption function is largely lost, and so far, various additives have been used to stabilize unstable neon light-absorbing dyes in pressure-sensitive adhesives. It has been broken. (See Patent Document 4)

In recent years, tetraazaporphyrin dyes are often used as neon light absorbing dyes instead of cyanine dyes. (See Patent Document 5)
Tetraazaporphyrin dyes are stable in the pressure-sensitive adhesive without any additives and have better durability than cyanine dyes.

As the pressure-sensitive adhesive, a pressure-sensitive adhesive composed of a highly versatile cross-linked acrylic resin and a cross-linking agent can be considered. However, depending on the monomer composition of the resin, sufficient durability, particularly sufficient light resistance, may not be obtained.

JP 2000-98131 A Japanese Patent No. 3753482 Japanese Patent Laid-Open No. 10-282335 JP 2007-233323 A Japanese Patent No. 3834479

A pressure-sensitive adhesive comprising a cross-linkable acrylic resin and a cross-linking agent, wherein the pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive containing a neon light-absorbing dye is provided on one side of a transparent substrate, for an optical filter having excellent light resistance It is an object of the present invention to develop a film and an optical filter for a plasma display panel using the film.

As a result of diligent research to solve the above problems, the present inventors have used a pressure-sensitive adhesive containing a neon light-absorbing dye by using a cross-linkable acrylic resin having a specific monomer composition and a cross-linking agent. It was found that an optical film provided with a pressure-sensitive adhesive layer on one surface of a transparent substrate and an optical filter for a plasma display panel using the same can maintain excellent stability in a light resistance test, and the present invention has been completed. .

That is, the present invention relates to (1) (a) 70.1 to 99.8% by weight of (meth) acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group, and (b) copolymerizing with component (a). 0.1 to 10% by weight of a possible hydroxyl group-containing monomer and / or 0.1 to 19.9% by weight of (c) another monomer copolymerizable with the component (a) and the component (b) (A) + (b) + (C) is 100% by weight) and is a pressure-sensitive adhesive comprising a cross-linking acrylic resin and a cross-linking agent, and the pressure-sensitive adhesive layer made of the pressure-sensitive adhesive is transparent. An optical filter film, characterized in that it is provided on one side of a substrate, and the pressure-sensitive adhesive layer contains a neon light-absorbing dye,
(2) The film for optical filters as described in (1) above, wherein the crosslinking agent is a block type isocyanate,
(3) The film for optical filters according to (1) or (2), wherein the neon light absorbing dye is a tetraazaporphyrin dye,
(4) The film for optical filters according to any one of (1) to (3), wherein the pressure-sensitive adhesive contains a tackifier made of a terpene phenol resin,
(5) At least one layer selected from a hard coat layer, a conductive layer, an antiglare layer and an antireflection layer is laminated on the surface opposite to the surface having the adhesive layer of the transparent substrate provided with the adhesive layer. The film for optical filters according to any one of (1) to (4),
(6) An optical filter for a plasma display panel, wherein the optical filter film according to any one of (1) to (5) is laminated on a film or glass having a near infrared ray and / or electromagnetic wave shielding function. ,
About.

The pressure-sensitive adhesive used in the present invention exhibits excellent stability even when it contains a neon light-absorbing dye typified by a tetraazaporphyrin dye, and the pressure-sensitive adhesive layer is provided on one surface of a transparent substrate. Films and optical filters for plasma display panels using the same exhibit excellent light resistance.

The pressure-sensitive adhesive used in the present invention is capable of copolymerizing 70.1 to 99.8% by weight of (meth) acrylic acid alkyl ester having an alkyl group with 4 to 12 carbon atoms and the above (meth) acrylic acid alkyl ester. 0.1 to 10% by weight of the hydroxyl group-containing monomer and 0.1 to 19.9% by weight of another monomer copolymerizable with the (meth) acrylic acid alkyl ester and the hydroxyl group-containing monomer were copolymerized. It is a pressure-sensitive adhesive comprising a crosslinkable acrylic resin and a crosslinker.

The (meth) acrylic acid alkyl ester used in the present invention is not particularly limited as long as it is a (meth) acrylic acid alkyl ester having an alkyl group having 4 to 12 carbon atoms. For example, butyl (meth) acrylate, ( Isobutyl acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, isopentyl (meth) acrylate, neopentyl (meth) acrylate, (meth) acrylic acid Hexyl, heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, (meth) acrylic Decyl acid, isodecyl (meth) acrylate, undecyl (meth) acrylate Although like (meth) acrylate, dodecyl these may be used in combination of two or more as necessary. Among these, butyl acrylate can be preferably used.

As the hydroxyl group-containing monomer copolymerizable with the (meth) acrylic acid alkyl ester, those functioning as a crosslinking point with a crosslinking agent to be described later are used, and the type thereof is not particularly limited, but (meth) acrylic acid Examples thereof include hydroxyethyl and hydroxypropyl (meth) acrylate, and these may be used in combination of two or more as required. Among these, 2-hydroxyethyl acrylate can be preferably used.

Other monomers that can be copolymerized with the (meth) acrylic acid alkyl ester and the hydroxyl group-containing monomer are not particularly limited, but (meth) acrylic acid alkyl esters in which the alkyl group has 1 to 3 carbon atoms, (meth) Non-aromatic ring-containing (meth) acrylic acid ester such as isobornyl acrylate, aromatic ring-containing (meth) acrylic acid ester such as (meth) acrylic acid arylalkyl ester, N, N-dimethyl (meth) acrylamide, etc. (N-substituted) amide monomers, epoxy group-containing acrylic monomers such as glycidyl (meth) acrylate, and the like. These may be used in combination of two or more. Among these, methyl acrylate can be preferably used.

The monomer is usually dissolved or dispersed in an organic solvent such as toluene, xylene, benzene, hexane, heptane, ethyl acetate, butyl acetate, methyl isobutyl ketone, methyl ethyl ketone, acetone, alcohols, and the polymerization initiator is stirred. A cross-linked acrylic resin can be obtained by adding and copolymerizing. The polymerization initiator used here may be either an inorganic or organic polymerization initiator. For example, organic polymerization such as azobisisobutyronitrile (hereinafter abbreviated as AIBN) or benzyl peroxide. It is preferred to use an initiator. The amount of the polymerization initiator used may be a normal amount, and can be selected, for example, from a range of about 0.01 to 1 part by weight with respect to 100 parts by weight of all monomer components.

Examples of the crosslinking agent used for the crosslinked acrylic resin include polyisocyanate compounds, melamine compounds, diamine compounds, epoxy resin compounds, urea resin compounds, metal salts such as aluminum chloride, ferric chloride, and aluminum sulfate. Polyisocyanate compounds are preferred, and block-type polyisocyanates are more preferred. Examples of the block type polyisocyanate include oxime block type isocyanate and active methylene block isocyanate. Low temperature curing type active methylene block isocyanate which does not require a catalyst such as a tin compound can be preferably used.

Adhesives using the above-mentioned crosslinkable acrylic resins and crosslinkers are excellent in adhesion and cohesion, and are highly stable against light and oxygen because there are no unsaturated bonds in the polymer. Also, the type and molecular weight of the monomer The weight average molecular weight is preferable in order to obtain a polymer having a sufficient crosslinking density immediately after coating and drying for the stability of the neon light absorbing dye before and after the aging operation. It is preferably 1 million or more.

As the tackifier used in the present invention, terpene tackifier resin, phenol tackifier resin, rosin tackifier resin, epoxy tackifier resin, polyamide tackifier resin, ketone tackifier resin, elastomer tackifier Examples thereof include terpene phenol resins, which are modified terpene resins.

The neon light absorbing dye used in the present invention preferably has an absorption maximum at a wavelength of 580 to 600 nm and a half width of about 10 nm to 60 nm, such as cyanine, squarylium, xanthene, oxonol, azo, tetraazaporphyrin, etc. A tetraazaporphyrin dye represented by the formula (1) can be suitably used. Tetraazaporphyrin dyes are also commercially available, and examples include “PD319” (manufactured by Mitsui Chemicals) and “TAP2” (manufactured by Yamada Chemical Co., Ltd.) (absorption wavelength peak is 592 nm).

（式中、Ｒ_１～Ｒ_８はアルキル基等を表し、Ｍは２個の水素原子、または２価の金属、３価、もしくは４価の金属誘導体を表す。）
色素の配合量は、適宜設定すればよく、吸収の極大値における透過率が５から７０％になるように配合することが好適である。

(Wherein R ₁ to R ₈ represent an alkyl group or the like, and M represents two hydrogen atoms, or a divalent metal, trivalent, or tetravalent metal derivative.)
What is necessary is just to set the compounding quantity of a pigment | dye suitably, and it is suitable to mix | blend so that the transmittance | permeability in the maximum value of absorption may be 5 to 70%.

In order to produce the film of the present invention, for example, 100 parts by weight of the above-mentioned cross-linked acrylic resin, 0.01 to 1 part by weight of a cross-linking agent, 0.01 to 1 part by weight of a neon light-absorbing dye, and other UV absorbers A pressure-sensitive adhesive obtained by dispersing 0.1 to 10 parts by weight of the above additive in a solvent may be applied onto a transparent substrate and dried. Examples of the solvent include alcohols such as methanol, ethanol, isopropanol, diacetone alcohol, ethyl cellosolve, methyl cellosolve, ketones such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, N, N-dimethylformamide, N, N— Amides such as dimethylacetamide, sulfoxides such as dimethyl sulfoxide, ethers such as tetrahydrofuran, dioxane and ethylene glycol monomethyl ether, esters such as methyl acetate, ethyl acetate and butyl acetate, chloroform, methylene chloride, dichloroethylene and trichloroethylene Halogen solvents, aromatics such as benzene, toluene, xylene, monochlorobenzene and dichlorobenzene, or aliphatic charcoal such as n-hexane and n-heptane Fluorine solvents such as hydrogen, tetrafluoropropyl alcohol, pentafluoropropyl alcohol, etc. can be used, the solubility of each composition is good, there is no problem of coating, drying, etc., and sufficient consideration is given to safety It is necessary to select a solvent.

The adhesive is applied by a known coating method such as a flow coating method, a spray method, a bar coating method, a gravure coating method, a roll coating method, a blade coating method, an air knife coating method, a lip coating method, or a die coater method. The coating layer is usually applied to a final film thickness of 5 to 50 μm, preferably 15 to 30 μm, and dried at 80 to 140 ° C., preferably 100 to 130 ° C. to fix the treatment layer. Usually, an aging process is performed thereafter. The conditions for the aging treatment vary depending on the type of resin used and the crosslinking agent, but the adhesive is preferably stored in a thermostatic bath at 25 to 50 ° C. for about 1 day to 1 week.

The type and thickness of the transparent substrate used in the present invention is not particularly limited as long as it is highly transparent, has no scratches, and can withstand use as an optical film, but has a thickness of 10 to 500 μm. It can be said that the workability is good and preferable. Specific examples include polymeric resin films such as polyester (hereinafter referred to as PET), polycarbonate, triacetate, norbornene, acrylic, cellulose, polyolefin, or urethane, and absorbs ultraviolet rays from the outside. In order to stabilize the function of the internal member, a transparent support film containing an ultraviolet absorbing material can also be used. The surface of the film may be coated with corona discharge treatment, plasma treatment, glow discharge treatment, roughening treatment, chemical treatment, anchor coating agent, primer or the like in order to improve adhesion with the coating film. . In addition, if the transparent substrate is a film having one or more functions such as anti-reflection, anti-glare / anti-reflection, antistatic, antifouling, near infrared absorptivity, electromagnetic wave shielding or color tone adjustment More preferably, particularly when a neon light absorbing adhesive layer is provided on them, these functions and the neon light absorbing ability can be held at the same time. An optical filter for a plasma display panel using can be obtained.

Next, examples of the transparent support film having the above-described functionality will be described below, but the present invention is not limited thereto.
The anti-reflection film is a film or a transparent support film in which the reflection of light from the outside is suppressed by coating a surface of a transparent support film such as PET with a low refractive index agent together with a binder resin and other additives, and a low refractive index layer. A film with a hard coat layer and a high refractive index layer provided between them to control the reflected light from each layer to cancel and improve visibility. A film that contains fine particles in other layers and diffuses light from outside to improve visibility. Arktop series (Asahi Glass Co., Ltd.), Kayacoat ARS series (Nippon Kayaku Co., Ltd.) , Kayacoat AGRS series (manufactured by Nippon Kayaku Co., Ltd.), Realak series (manufactured by NOF Corporation), etc. Can be used as a beam, these can be obtained from the market.

The method of shielding electromagnetic waves is a mesh type in which a fine pattern of metal such as copper is held on a transparent base material with a fine metal wire such as copper, and an ultra-thin metal film within a transparent base There is a thin film type held in glass. The thin film type generally reflects and does not transmit near-infrared light, and therefore does not require a separate near-infrared absorbing layer. As the transparent substrate having other functionality used in the present invention, there is a film that has a single function or a plurality of functions such as ultraviolet absorptivity, antistatic property, antifouling property, and color tone adjustment. These can be prepared according to a method known per se by a method of molding from a binder resin composition containing a compound having these properties.

Next, the optical filter of the present invention has the neon light-absorbing film of the present invention in which the present adhesive layer is provided on a transparent substrate as a minimum component, and the neon light-absorbing film and other functions are transparent. It is obtained by laminating a substrate or glass (for example, a film or glass having a near infrared ray and / or electromagnetic wave shielding function). The optical filter of the present invention may be bonded in advance to a glass plate or a plastic plate and attached to the front surface of the plasma display, or may be used by directly bonding.

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to such examples. In Examples, “part” means “part by weight” and “%” means “% by weight”.

The weight average molecular weight of the used adhesive was measured on the following conditions of GPC (gel permeation chromatography) method.
Analyzer: Showa Denko, GPC SYSTEM-21 Shodex
Column: Showa Denko KF-803L + KF-803L + KF-803L
Column temperature: 40 ° C
Flow rate: 1 ml / min
Eluent: Tetrahydrofuran Detector: Differential refractometer Standard sample: Polystyrene

Example 1
<Production of acrylic resin>
A polymerization vessel was charged with 90 parts of butyl acrylate, 9.5 parts of methyl acrylate, 0.5 part of 2-hydroxyethyl acrylate, and 150 parts of ethyl acetate, and purged with nitrogen at room temperature for 1 hour. Then, it heated up at 75 degreeC under stirring, 0.02 part of AIBN was added as a polymerization initiator, and it superposed | polymerized at 75 degreeC for 6 hours, and produced the acrylic ester polymer. The weight average molecular weight of this acrylate ester polymer was 1 million.
<Preparation of neon light absorption film>
A coating solution in which the materials shown in the table below were mixed and dissolved using the acrylate polymer (acrylic resin) prepared as described above in a uniform manner was added to MRF-38 (trade name, release PET film, Mitsubishi Chemical). A pressure-sensitive adhesive layer was formed on a polyester film by a comma coater at a coating speed of 0.8 m / min and a drying temperature of 110 ° C. so that the thickness of the pressure-sensitive adhesive layer was 18 μm. Next, the KAYACOAT ARS-E105-100UV (trade name, anti-reflective film, manufactured by Nippon Kayaku Co., Ltd.) reduces the thickness by bonding two films so that the adhesive layer is formed on the opposite surface of the anti-reflective surface. A reflective neon light absorbing film was obtained.
<Production of optical filter for PDP>
The neon light-absorbing film was bonded onto a film having a metal multilayer sputtered film having an adhesive layer to obtain an optical filter for PDP. This filter may be directly attached to the front surface of the PDP module, or may be attached to a transparent plate such as a glass plate and attached to the front of the module, and sufficiently exhibits the performance required as a PDP filter.

Materials Amount used Acrylic resin 14.0 parts Crosslinker (trade name K6000; manufactured by Asahi Kasei Chemicals Corporation) 0.07 part additive (trade name K140; manufactured by Yasuhara Chemicals Co., Ltd.) 0.25 parts UV absorber ( Brand name Tinuvin 109; Ciba Geigy Co., Ltd.) 0.2 parts Neon light absorbing dye (trade name PD319; Mitsui Chemicals Co., Ltd.) 0.005 parts Methyl ethyl ketone 14.5 parts

Example 2
<Production of acrylic resin>
A polymerization vessel was charged with 70 parts of 2-ethylhexyl acrylate, 29.5 parts of methyl acrylate, 0.5 parts of 2-hydroxyethyl acrylate, and 150 parts of ethyl acetate, and purged with nitrogen at room temperature for 1 hour. Then, it heated up at 75 degreeC under stirring, 0.02 part of AIBN was added as a polymerization initiator, and it superposed | polymerized at 75 degreeC for 6 hours, and produced the acrylic ester polymer. The weight average molecular weight of this acrylic ester polymer was 1,050,000.
<Preparation of neon light absorption film>
A neon light-absorbing film having reduced reflectivity was obtained in the same manner as in Example 1 except that the acrylic resin in Example 1 was changed.
<Production of optical filter for PDP>
The neon light-absorbing film was bonded onto a metal multilayer sputtered film having an adhesive layer to obtain an optical filter for PDP. This filter may be directly attached to the front surface of the PDP module, or may be attached to a transparent plate such as a glass plate and attached to the front of the module, and sufficiently exhibits the performance required as a PDP filter.

Example 3
<Production of acrylic resin>
A polymerization vessel was charged with 90 parts of butyl acrylate, 2 parts of methyl acrylate, 0.5 part of 2-hydroxyethyl acrylate, 7.5 parts of glycidyl methyl acrylate, and 150 parts of ethyl acetate, and purged with nitrogen at room temperature for 1 hour. went. Then, it heated up at 75 degreeC under stirring, 0.02 part of AIBN was added as a polymerization initiator, and it superposed | polymerized at 75 degreeC for 6 hours, and produced the acrylic ester polymer. The weight average molecular weight of this acrylic ester polymer was 1,040,000.
<Preparation of neon light absorption film>
A neon light-absorbing film having reduced reflectivity was obtained in the same manner as in Example 1 except that the acrylic resin in Example 1 was changed.
<Production of optical filter for PDP>
The neon light-absorbing film was bonded onto a metal multilayer sputtered film having an adhesive layer to obtain an optical filter for PDP. This filter may be directly attached to the front surface of the PDP module, or may be attached to a transparent plate such as a glass plate and attached to the front of the module, and sufficiently exhibits the performance required as a PDP filter.

Comparative Example 1
<Production of acrylic resin>
A polymerization vessel was charged with 80 parts of butyl acrylate, 18 parts of methyl acrylate, 2 parts of acrylic acid, and 150 parts of ethyl acetate, and was purged with nitrogen at room temperature for 1 hour. Then, it heated up at 75 degreeC under stirring, 0.02 part of AIBN was added as a polymerization initiator, and it superposed | polymerized at 75 degreeC for 6 hours, and produced the acrylic ester polymer. The weight average molecular weight of this acrylate ester polymer was 1,000,000.
<Preparation of neon light absorption film>
A neon light-absorbing film having reduced reflectivity was obtained in the same manner as in Example 1 except that the acrylic resin in Example 1 was changed.

Comparative Example 2
<Production of acrylic resin>
A polymerization vessel was charged with 96 parts of butyl acrylate, 4 parts of acrylic acid, and 150 parts of ethyl acetate, and was purged with nitrogen at room temperature for 1 hour. Then, it heated up at 75 degreeC under stirring, 0.02 part of AIBN was added as a polymerization initiator, and it superposed | polymerized at 75 degreeC for 6 hours, and produced the acrylic ester polymer. The weight average molecular weight of this acrylate ester polymer was 1.09 million.
<Preparation of neon light absorption film>
A neon light-absorbing film having reduced reflectivity was obtained in the same manner as in Example 1 except that the acrylic resin in Example 1 was changed.

Comparative Example 3
<Production of acrylic resin>
A polymerization vessel was charged with 80 parts of butyl acrylate, 13 parts of methyl acrylate, 2 parts of acrylic acid, 5 parts of acrylic acid N, N-dimethylamide, and 150 parts of ethyl acetate, and purged with nitrogen at room temperature for 1 hour. Then, it heated up at 75 degreeC under stirring, 0.02 part of AIBN was added as a polymerization initiator, and it superposed | polymerized at 75 degreeC for 6 hours, and produced the acrylic ester polymer. The weight average molecular weight of this acrylate ester polymer was 1.70 million.
<Preparation of neon light absorption film>
A neon light-absorbing film having reduced reflectivity was obtained in the same manner as in Example 1 except that the acrylic resin in Example 1 was changed.

<Test method>
The luminous transmittance (Y /%) and chromaticity coordinates (x, y) of the test piece of each example film and each comparative example film were measured, and an energy of 18 kJ / cm ² over 100 hours using a carbon arc fade meter. Then, luminous transmittance (Y /%) and chromaticity coordinates (x, y) were measured again.
The measurement uses UV-3150 (trade name, spectrophotometer, manufactured by Shimadzu Corporation), and the luminous transmittance (Y /%) and chromaticity coordinates (x, y) are colors according to the XYZ color system of JIS Z 8701. It was calculated in accordance with the display method.
As the carbon arc fade meter, an ultraviolet fade meter U48H (manufactured by Suga Test Instruments) was used.

The results before and after the light resistance test are shown in Table 1.

 

 

<Consideration of results>
In Examples 1 to 3, there was little change in color before and after the light resistance test, and good results were obtained even in the change in neon light absorption ability at 592 nm. In Comparative Examples 1 to 3, the color change before and after the light resistance test was large, and the change in neon light absorption ability was also large.

Claims (6)

(A) 70.1 to 99.8 wt% of (meth) acrylic acid alkyl ester having 4 to 12 carbon atoms in the alkyl group, and (b) 0.1 mol of hydroxyl group-containing monomer copolymerizable with component (a). ˜10 wt% and (c) other monomer copolymerizable with component (a) and component (b) in a proportion of 0.1 to 19.9 wt% ((a) + (b) + ( c) is a pressure-sensitive adhesive composed of a cross-linked acrylic resin and a cross-linking agent copolymerized at 100% by weight, and a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive is provided on one side of the transparent substrate. A film for optical filters, wherein the layer contains a neon light absorbing dye. The film for optical filters according to claim 1, wherein the crosslinking agent is a blocked isocyanate. The film for optical filters according to claim 1 or 2, wherein the neon light absorbing dye is a tetraazaporphyrin dye. The film for optical filters according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive contains a tackifier made of a terpene phenol resin. It is characterized in that at least one layer selected from a hard coat layer, a conductive layer, an antiglare layer and an antireflection layer is laminated on the surface opposite to the surface having the adhesive layer of the transparent substrate provided with the adhesive layer. The film for optical filters as described in any one of Claims 1 thru | or 4. An optical filter for a plasma display panel, wherein the optical filter film according to any one of claims 1 to 5 is laminated on a film or glass having a near-infrared ray and / or electromagnetic wave shielding function.