JP2007079462A - Filter for display and display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter for a display which has superior stability of spectral characteristic variation caused by coloring matter deterioration in spite of long-time use and long-time use, especially, in a high-temperature and high-humidity environment and also has sufficient adhesive strength with a support base material, and the display to which the filter for the display is applied. <P>SOLUTION: The filter for the display has a stack structure of at least the support base material and a coloring matter layer containing binder resin and coloring matter. The coloring matter layer contains a diimmonium compound represented by a specific expression as the coloring matter, and glass transition temperature of the binder resin is 65 to 140°C; and an acid number is 0.1 to 10, and the remaining solvent amount in the coloring matter layer is 1 to 250 mg/m<SB>2</SB>. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a display filter and a display using the same.
More specifically, the present invention relates to a display filter and a display that are excellent in stability of spectral characteristics even under long-term use and have sufficient adhesion to a supporting substrate.

In recent years, electronic displays such as CRTs (CRTs), LCDs (Liquid Crystal Displays), PDPs (Plasma Displays), organic / inorganic EL displays, FEDs (Field Emission Displays) have been used as display panels for various electronic devices.
A filter is installed on the front surface of such an electronic display in order to remove unnecessary light-emitting components and make the display color clear. For example, in a plasma display, a mixed gas of xenon and neon is excited by discharge to emit vacuum ultraviolet light, and light emission of three primary colors is obtained by using light emission of red, blue and green phosphors by the vacuum ultraviolet light excitation. Yes. At that time, after neon atoms are excited, neon orange light centered around 590 nm is emitted when returning to the ground state. Therefore, the plasma display has a disadvantage that orange is mixed with red and vivid red cannot be obtained. is there. On the other hand, when the xenon atom is excited and returns to the ground state, near infrared rays in the vicinity of 800 to 1100 nm are generated in addition to ultraviolet rays, and the generated near infrared rays cause malfunction of peripheral devices. For this reason, in plasma displays, a filter that absorbs and removes neon orange light and near-infrared light, such as a filter that locally reduces the transmittance of neon orange light and near-infrared wavelengths, is installed on the front of the display. is doing. Further, the filter may have a function of correcting the color balance of the image or improving the color purity by adjusting the transmittance in the visible light wavelength region.

In these display filters, functional dyes are generally used as components that exhibit the above functions. However, a display filter using a dye has a problem that a spectral characteristic attributed to the deterioration of the dye occurs due to use for a long time, particularly under high temperature or high humidity.
In addition, the display filter often takes a configuration in which a functional layer that expresses the above functions is laminated on a support base material.In this case, the support base material and the functional layer do not have sufficient adhesion. Separation or bubbles may occur over time.
Conventionally, in order to provide sufficient adhesion between the support substrate and the functional layer, an adhesive layer is provided between the support substrate and the functional layer, or the adhesion to the support substrate is improved. Such processing is performed. However, when taking the layer structure which provides a functional layer on both surfaces of a support base material, it may be unsuitable to perform the process which makes adhesiveness favorable on the surface of a support base material. There is also a demand to eliminate the pressure-sensitive adhesive layer, reduce the number of layers as much as possible, simplify the manufacturing process, and increase productivity. Then, it is calculated | required that it has sufficient adhesiveness without passing through an adhesive also with respect to the support base material which has not performed the surface treatment from which adhesiveness becomes favorable.

For example, Patent Document 1 proposes a method of using an acrylic resin having a glass transition temperature of 110 ° C. or higher as a binder resin for the purpose of providing a display filter having excellent durability such as heat resistance and light resistance. .
Patent Document 2 discloses a near-infrared absorbing layer for the purpose of providing a near-infrared absorbing filter that has high transmittance in the visible light region and has stable spectral characteristics even when left at high temperature and high humidity for a long time. A near-infrared absorption filter has been proposed in which the residual solvent amount is 0.05 to 5% by weight and the glass transition temperature of the binder resin of the near-infrared absorption layer is 85 to 140 ° C.

JP 2003-167119 A Japanese Patent No. 3334141

However, Patent Document 1 does not describe the amount of residual solvent in the dye layer, and therefore when the amount of residual solvent is large, the glass transition temperature of the binder resin in the dye layer state is higher than the glass transition temperature of the binder resin itself. As a result, the temperature is lower than the operating temperature of the device in which the display filter is used, and the pigment is deteriorated. Furthermore, there is a problem that sufficient adhesion with the support substrate cannot be obtained.
Further, according to the method of Patent Document 2, although the durability of the pigment is improved, it may be insufficient, and it is only mentioned that the adhesion is easily adhered to the support substrate. In some cases, the method described in this document may have insufficient adhesion.

  The object of the present invention is to provide excellent stability of spectral characteristics attributed to dye deterioration even when used for a long time, particularly at high temperatures or under high humidity, and has sufficient adhesion to a supporting substrate. It is an object of the present invention to provide a display filter and a display to which the display filter is applied.

  As a result of intensive studies in view of the above problems, the present inventors have determined that the above problems can be achieved by setting the residual solvent amount of the dye layer having at least a near infrared absorption function, and the glass transition temperature and acid value of the binder resin within a specific range. The inventors have found that this can be solved, and have completed the present invention.

The display filter of the present invention is a display filter having a laminated structure in which at least a support substrate and a dye layer containing a binder resin and a dye are laminated, and the dye is represented by at least the following formula (1). The binder resin has a glass transition temperature of 65 to 140 ° C. and an acid value of 0.1 to 10, and the residual solvent amount in the dye layer is in the range of 1 to 250 mg / m ² . It is characterized by being.

（式中、Ｒ₁〜Ｒ₈は、水素原子、アルキル基、アリール基、アルケニル基、アラルキル基、又はアルキニル基を表し、それぞれ同じであっても、異なっていても良い。Ｒ₉〜Ｒ₁₂は、水素原子、ハロゲン原子、アミノ基、シアノ基、ニトロ基、カルボキシル基、アルキル基、又はアルコキシ基を表し、それぞれ同じであっても、異なっていても良い。Ｒ₁〜Ｒ₁₂で置換基を結合できるものは置換基を有しても良い。Ｘ^-は陰イオンを表す。）

(Wherein R _{1 to} R ₈ represent a hydrogen atom, an alkyl group, an aryl group, an alkenyl group, an aralkyl group, or an alkynyl group, and may be the same or different. R _{9 to} R ₁₂ It represents a hydrogen atom, a halogen atom, an amino group, a cyano group, a nitro group, a carboxyl group, an alkyl group, or alkoxy group, even each same may be different .R ₁ to R ₁₂ substituents May be substituted, and X ⁻ represents an anion.)

The diimmonium compound represented by the formula (1) has a large absorption in the near infrared region, a wide absorption region, and a high transmittance in the visible region. However, there is a problem that it is easily denatured under high temperature and high humidity, and absorption in the near infrared region becomes small.
Further, when using a near-infrared absorbing dye having a counter ion like the above diimmonium compound, the binder resin has an acid group or a hydroxyl group, or a polymerization initiator or the like is blended in the binder resin. If so, the acid group or hydroxyl group, or the polymerization initiator or the like may break the equilibrium state of the matrix of the near-infrared absorbing dye and the counter ion, making it difficult to perform the near-infrared absorption function. .
On the other hand, when the diimonium compound is included as a dye, the glass transition temperature and the acid value include a binder resin in the above range, and the residual solvent amount in the dye layer is in the above range, at least has a near infrared shielding function, It is possible to obtain a display filter that is excellent in stability of spectral characteristics and has sufficient adhesion, without causing dye deterioration even under high temperature and high humidity.

  In the display filter of the present invention, it is preferable that the binder resin has a hydroxyl value of 10 or less from the viewpoint of further improving the durability of the dye and obtaining a display filter having excellent durability.

In the display filter of the present invention, it is preferable that at least one of R _{1 to} R ₈ in the formula (1) is a branched alkyl group. R _{1 to} R ₈ are preferably branched alkyl groups from the viewpoint that the thermal decomposition point of the dye is increased and the heat resistance is improved, so that the stability of the display filter is also improved.
In the display filter of the present invention, the anion X ⁻ in the diimmonium compound represented by the formula (1) is preferably a sulfonylimide acid ion. In this case, the durability of the dye is further improved, and a display filter having excellent heat resistance can be obtained.

The display filter of the present invention can have a function of having an absorption maximum of light transmittance at least at 570 to 610 nm. In such a case, at least orange light emission from the display can be suppressed, and a bright red color can be obtained.
The display filter of the present invention can have a function of having an absorption maximum of light transmittance at least at a wavelength of 380 to 570 nm or 610 to 780 nm. In such a case, the function of correcting the color balance of the image or improving the color purity can be provided by adjusting the transmittance in the wavelength region of visible light.
The display filter of the present invention may contain an ultraviolet absorber in the binder resin. In this case, it is possible to further improve the durability of various resin materials and other constituent materials (for example, a binder resin and a pigment) that constitute the display.

The display filter of the present invention may have one layer or two or more layers having one or two or more of an electromagnetic wave shielding function, an antireflection function, an antiglare function, an antifouling function, and an ultraviolet absorption function. preferable.
The display according to the present invention is characterized in that the display filter is disposed on a display surface of the display.

  ADVANTAGE OF THE INVENTION According to this invention, the filter for a display which is excellent in stability of the spectral characteristics attributed to pigment deterioration under long-time use, especially under high temperature and high humidity, and excellent in adhesiveness with a support substrate can be provided. In addition, the present invention can provide a display using such a display filter.

The display filter of the present invention is a display filter having a laminated structure in which at least a support substrate and a dye layer containing a binder resin and a dye are laminated, and the dye is represented by at least the following formula (1). The binder resin has a glass transition temperature of 65 to 140 ° C. and an acid value of 0.1 to 10, and the residual solvent amount in the dye layer is in the range of 1 to 250 mg / m ² . It is characterized by being.

（式中、Ｒ₁〜Ｒ₈は、水素原子、アルキル基、アリール基、アルケニル基、アラルキル基、又はアルキニル基を表し、それぞれ同じであっても、異なっていても良い。Ｒ₉〜Ｒ₁₂は、水素原子、ハロゲン原子、アミノ基、シアノ基、ニトロ基、カルボキシル基、アルキル基、又はアルコキシ基を表し、それぞれ同じであっても、異なっていても良い。Ｒ₁〜Ｒ₁₂で置換基を結合できるものは置換基を有しても良い。Ｘ^-は陰イオンを表す。）

(Wherein R _{1 to} R ₈ represent a hydrogen atom, an alkyl group, an aryl group, an alkenyl group, an aralkyl group, or an alkynyl group, and may be the same or different. R _{9 to} R ₁₂ It represents a hydrogen atom, a halogen atom, an amino group, a cyano group, a nitro group, a carboxyl group, an alkyl group, or alkoxy group, even each same may be different .R ₁ to R ₁₂ substituents May be substituted, and X ⁻ represents an anion.)

The diimmonium compound represented by the formula (1) has a large absorption in the near infrared region, a wide absorption region, and a high transmittance in the visible region. However, there is a problem that it is easily denatured under high temperature and high humidity, and absorption in the near infrared region becomes small.
As a near-infrared absorbing dye such as the above-mentioned diimmonium compound, when a dye having a counter ion is used for the dye layer, the binder resin has an acid group or a hydroxyl group, or a polymerization initiator is blended in the binder resin. In such a case, the balance between the mother skeleton of the near-infrared absorbing dye and the counter ion may be disrupted by the acid group or hydroxyl group, or the polymerization initiator, and it may be difficult to perform the function of absorbing near-infrared light. is there.
On the other hand, when the dye contains the above diimmonium compound, the glass transition temperature and the acid value contain a binder resin in the range of the present invention, and the residual solvent amount in the dye layer is in the above range, it has at least a near infrared shielding function. In addition, it is possible to obtain a display filter that does not undergo dye deterioration even under high temperature and high humidity, is excellent in stability of spectral characteristics, and has sufficient adhesion.

(Layer structure of display filter)
1 to 4 are cross-sectional views illustrating a laminated structure of a display filter according to the present invention.
The display filter according to the present invention is most basically a laminate 4 having a structure in which a support substrate 2 and a dye layer 3 are laminated adjacently as indicated by reference numeral 1 in FIG. The support substrate 2 may be subjected to a surface treatment for improving adhesion that can be performed during lamination. Further, an adhesive layer may be provided between the support substrate 2 and the dye layer 3, but in the display filter of the present invention, the dye layer has sufficient adhesion to the support substrate, Even with respect to a support substrate that has not been subjected to a surface treatment for improving adhesion, it has sufficient adhesion without interposing an adhesive layer.

  In the present invention, for example, as shown in FIG. 2, a functional layer 5 known in the field of optical filters is further provided on the laminate 4 composed of the support substrate 2 and the dye layer 3 as necessary. The display filter 11 can be obtained. The functional layer 5 is preferably a single layer or two or more layers having one or more of an electromagnetic wave shielding function, an antireflection function, an antiglare function, an antifouling function, and an ultraviolet absorption function.

In FIG. 2, the functional layer 5 is laminated on the dye layer 3, but the laminated structure is not limited to these. For example, as shown in FIG. 3, the dye layer 3 is provided on one side of the support base 2. The functional layer 5 may be laminated on the back surface of the surface of the support substrate 2 on which the dye layer 3 is laminated. Further, as shown in FIG. 4, a structure in which another functional layer 5 ′ is further laminated on the dye layer 3 in FIG. The laminated structure of the display filter of the present invention is not limited to the above example.
Hereinafter, each layer of the display filter will be described.

[Dye layer]
The said pigment | dye layer contains binder resin and a pigment | dye at least, and can contain an additive as needed. Further, the dye layer contains a solvent that remains without being dried in the method of forming the dye layer described later.

[Dye]
The dye layer contains at least the diimmonium compound represented by the above formula (1) that functions as a near-infrared absorbing dye, and absorbs neon light having an absorption maximum at least at 570 to 610 nm, for example. A dye for the purpose (hereinafter referred to as “neon light-absorbing dye”), or a dye for the purpose of color tone adjustment having an absorption maximum at 380 to 570 nm or 610 to 780 nm (hereinafter referred to as “color tone adjusting dye”) In addition, a near-infrared absorbing dye having an absorption maximum at least at 800 to 1100 nm can be contained. These pigments may be used alone or in combination of two or more.

(Near-infrared absorbing dye)
The diimmonium compound represented by the formula (1) is characterized by having a large absorption in the near infrared region, a wide absorption region, and a high transmittance in the visible region.
Specific examples of R _{1 to} R ₈ in the formula (1), which is an essential dye contained in the dye layer, include a methyl group, an ethyl group, and n-propyl as an alkyl group which may have a substituent. Group, iso-propyl group, n-butyl group, iso-butyl group, ter-butyl group, n-amyl group, n-hexyl group, n-octyl group, 2-hydroxyethyl group, 2-cyanoethyl group, 3- Examples thereof include a hydroxypropyl group, a 3-cyanopropyl group, a methoxyethyl group, an ethoxyethyl group, and a butoxyethyl group. Examples of the aryl group which may have a substituent include a phenyl group, a fluorophenyl group, a chlorophenyl group, a tolyl group, diethylaminophenyl, and a naphthyl group. In addition, examples of the alkenyl group which may have a substituent include a vinyl group, a propenyl group, a butenyl group, and a pentenyl group. Examples of the aralkyl group which may have a substituent include a benzyl group, a p-fluorobenzyl group, a p-chlorophenyl group, a phenylpropyl group, and a naphthylethyl group. Among these, branched alkyl groups such as iso-propyl group, iso-butyl group, and ter-butyl group are preferable from the viewpoint of increasing the thermal decomposition point of the dye and improving the durability. At least one of R _{1 to} R ₈ is preferably a branched alkyl group, and all of R _{1 to} R ₈ are more preferably branched alkyl groups.

R _{9 to} R ₁₂ include hydrogen, fluorine, chlorine, bromine, diethylamino group, dimethylamino group, cyano group, nitro group, methyl group, ethyl group, propyl group, trifluoromethyl group, methoxy group, and ethoxy group. And propoxy group.

X ⁻ is an inorganic monovalent anion, for example, a halogen ion such as fluorine ion, chlorine ion, bromine ion or iodine ion, thiocyanate ion, hexafluoroantimonate ion, perchlorate ion, periodate ion, Examples thereof include nitrate ion, tetrafluoroborate ion, hexafluorophosphate ion, molybdate ion, tungstate ion, titanate ion, vanadate ion, phosphate ion and borate ion. Further, X ^- is a 1 dianion of an organic acid, e.g., acetate ion, lactate ion, trifluoroacetate ion, propionate ion, benzoate ion, oxalate ion, succinate ion, organic carboxylate ion stearate Acid ion, methanesulfonate ion, toluenesulfonate ion, naphthalene monosulfonate ion, chlorobenzenesulfonate ion, nitrobenzenesulfonate ion, dodecylbenzenesulfonate ion, benzenesulfonate ion, ethanesulfonate ion, trifluoromethanesulfonate ion Organic sulfonate ions such as tetraphenylborate ions, butyltriphenylborate ions, and the like, and bischloromethanesulfonyl imido ion, bisdichloromethanesulfonyl Sulfonimidate ions such as imido ion, bistrichloromethanesulfonyl imido ion, bisfluorosulfonyl imido ion, bisdifluoromethanesulfonyl imido ion, bistrifluoromethanesulfonyl imido ion, bispentafluoroethanesulfonyl imido ion, etc. Is mentioned. Among these, a sulfonylimido acid ion is preferable from the viewpoint of stabilizing a diimmonium compound that is an ionic compound by strong electron-withdrawing property and, as a result, improving durability. Of these, bistrifluoromethanesulfonylimido ion is particularly preferred. However, the present invention is not limited to those mentioned above.

Some of these near-infrared absorbing dyes are commercially available, and for example, Kayasorb IRG-022, IRG-068, etc. manufactured by Nippon Kayaku Co., Ltd. can be suitably used.
The compounding amount of the diimmonium compound is preferably 0.08 to 30% by weight, more preferably 0.08 to 15% by weight, based on the solid content of the entire pigment.

The dye layer is a near-infrared absorbing dye having an absorption maximum of light transmittance at least at 800 to 1100 nm in addition to the diimmonium compound, and contains any compound as long as it can be added to the binder resin. be able to.
Specific examples of such near-infrared absorbing dyes include polymethine compounds, cyanine compounds, phthalocyanine compounds, naphthalocyanine compounds, naphthoquinone compounds, anthraquinone compounds, dithiol compounds, immonium compounds, and aminium. Compounds, pyrylium compounds, cerium compounds, squarylium compounds, copper complexes, nickel complexes, dithiol metal complexes organic near infrared absorbing dyes, tin oxide, indium oxide, magnesium oxide, titanium oxide, chromium oxide Zirconium oxide, nickel oxide, aluminum oxide, zinc oxide, iron oxide, ammonium oxide, lead oxide, bismuth oxide, inorganic near-infrared absorbing dyes such as lanthanum oxide, etc. can be used alone or in combination of two or more. . Among these, anthraquinone compounds, naphthoquinone compounds, and phthalocyanine compounds are preferable.

The type and amount of addition may be appropriately selected according to the absorption wavelength and absorption coefficient of the near-infrared absorbing dye, the color tone, the transmittance required for the display front plate, and the like.
The blending amount of the entire near-infrared absorbing dye is preferably 0.1 to 50% by weight, more preferably 0.1 to 25% by weight, based on the solid content of the entire dye layer.

(Neon light absorbing dye)
When the display filter according to the present invention is used for a plasma display, the dye layer may contain a neon light absorbing dye in order to absorb neon light emitted from the plasma display panel. The neon light absorption region has a wavelength of 570 to 610 nm, and is preferably designed so that the light transmittance at a wavelength of 570 to 610 nm is 50% or less.
Neon light absorbing dyes include dyes conventionally used as dyes having an absorption maximum of light transmittance in a wavelength region of at least 570 to 610 nm, for example, cyanine-based, oxonol-based, methine-based, subphthalocyanine-based or porphyrin And the like.
The blending amount of the neon light absorbing dye is preferably 0.01 to 10% by weight, more preferably 0.01 to 5% by weight, based on the solid content of the entire dye layer.
When the display filter according to the present invention is used for a display other than the plasma display panel, the dye layer may contain the neon light absorbing dye as a color tone adjusting dye.

(Color tone adjusting dye)
In order to adjust the color of the display filter in order to improve the color purity of light emitted from the panel, the color reproduction range, the display color when the power is turned off, the dye layer can contain a color tone adjusting dye. From known dyes having a maximum absorption wavelength in the visible region of 380 to 570 nm or 610 to 780 nm, any dye can be used in combination depending on the purpose. Examples of known dyes that can be used as the color tone adjusting dyes include the dyes described in JP 2000-275432 A, JP 2001-188121 A, JP 2001-350013 A, JP 2002-131530 A, and the like. Can be suitably used. In addition, other dyes such as anthraquinone, naphthalene, azo, phthalocyanine, pyromethene, tetraazaporphyrin, squarylium, and cyanine that absorb visible light such as yellow light, red light, and blue light. Can be used.
The blending amount of the color tone adjusting dye is preferably 0.01 to 10% by weight, more preferably 0.01 to 5% by weight, based on the solid content of the entire dye layer.

[Binder resin]
In the present invention, since the diimmonium compound represented by the formula (1) having a counter ion is used as the near-infrared absorbing dye, the binder resin has an acid group or a hydroxyl group, or is transparent. When a polymerization initiator or the like is blended in the binder resin, the equilibrium state between the mother skeleton of the near-infrared absorbing dye and the counter ion is disrupted by the acid group, the hydroxyl group, or the polymerization initiator. It may be difficult to perform the function. For the purpose of eliminating this, it is preferable to use a binder resin having a small acid value or hydroxyl value, and more preferably a resin having a small hydroxyl value or acid value. Here, the acid value is the number of mg of potassium hydroxide required to neutralize all acidic components (for example, carboxylic acid group, sulfonic acid group, phosphoric acid group, acrylic acid group, etc.) contained in 1 g of binder resin, The hydroxyl value refers to the number of mg of potassium hydroxide required to neutralize acetic acid bonded to all hydroxyl groups when 1 g of binder resin is acetylated. As a method for measuring the acid value and the hydroxyl value, a method defined in JIS K2501 or the like can be used. On the other hand, when there is no acid value or when the acid value is too small, there is a problem that adhesion is poor unless an easy adhesion treatment or the like is performed on the support substrate.

  Therefore, the acid value of the binder resin according to the present invention is 0.1 to 10. By setting the acid value to 10 or less, it is possible to prevent the near-infrared absorbing dye from reacting with the acid contained in the binder resin, so that the near-infrared absorbing function can be an optical filter that is stable over time. it can. On the other hand, when the acid value is 0.1 or more, the adhesion between the substrate and the dye layer is improved and sufficient. The acid value of the binder resin is more preferably 0.1-5.

The hydroxyl value of the binder resin according to the present invention is preferably 10 or less. By reducing the hydroxyl value in this way, the near-infrared absorbing layer contains, for example, the near-infrared absorbing dye having a counter ion can be prevented from reacting with the hydroxyl group of the binder resin. An optical filter whose function is stable over time can be obtained, and the range of selection of near-infrared absorbing dyes can be expanded. The hydroxyl value of the binder resin is more preferably 5 or less, and particularly preferably 0.
Further, the near-infrared absorbing dye having a counter ion is a diimmonium compound, a nickel complex, a dithiol complex, an aminium compound, a cyanine compound, a pyrylium compound, or the like.

  The glass transition temperature of the binder resin used for the pigment layer of the display filter of the present invention is 65 to 140 ° C. When the glass transition temperature is lower than the equipment use temperature, the glass transition temperature of the binder resin is the equipment use temperature because the dye deteriorates due to the interaction between the dye contained in the dye layer and the interaction between the dye and the binder resin. The above is preferable. For example, when a display filter is applied to the front surface of a plasma display which is a typical application, the screen surface is heated to a high temperature of about 60 ° C. due to heat dissipation associated with plasma discharge. The transition temperature needs to be at least 65 ° C. or higher. On the other hand, when the glass transition temperature of the resin exceeds 140 ° C., if the resin is dissolved in a solvent and sufficiently dried when coated on a transparent substrate, the temperature must be high and the heat resistance is weak. When a dye is used, the dye deteriorates. In addition, when dried at low temperature, the drying time is long and the productivity is deteriorated, and it is impossible to make an inexpensive near-infrared absorption filter. In addition, there is a possibility that sufficient drying cannot be performed, and the solvent remains in the coating film. However, as described above, the apparent glass transition temperature of the binder-resin is lowered, and there is a possibility of causing the modification of the dye.

Further, the binder resin used in the dye layer of the present invention needs to have transparency. The transparency of the binder resin is not particularly limited as long as it is transparent to humans, but the haze according to JIS K7105 is preferably 5 or less, and particularly preferably 3 or less. For example, an acrylic resin, a urethane resin, a fluorine resin, a polyester resin, or the like can be used. Among them, an acrylic resin is particularly preferable because it is excellent in transparency.
The binder resin used in the dye layer of the present invention may be either a curable resin or a plastic resin, but a plastic resin is more preferable from the viewpoint of suppressing dye deterioration.

The acrylic resin is a polymer having a repeating unit derived from at least (meth) acrylic acid and a (meth) acrylic monomer of these derivatives. Here, (meth) acrylic acid means acrylic acid and / or methacrylic acid.
Examples of the acrylic monomer include (meth) acrylic acid ester monomers such as (meth) acrylic acid alkyl ester monomers, and (meth) acrylic acid.
Examples of (meth) acrylic acid alkyl ester monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, sec-propyl (meth) acrylate, (meth) acrylic acid. n-butyl, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) acrylic acid Examples thereof include n-octyl, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, undecyl (meth) acrylate, and lauryl (meth) acrylate.

Furthermore, the acrylic resin used in the present invention includes, in addition to the above, a monomer having another functional group within a range that does not impair the glass transition temperature, acid value, and hydroxyl value of the specific range of the acrylic resin. May be copolymerized. Examples of monomers having other functional groups include monomers containing hydroxyl groups such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and allyl alcohol; (meth) acrylamide, N-methyl Monomers containing amide groups such as (meth) acrylamide and N-ethyl (meth) acrylamide; Monomers containing amide groups and methylol groups such as N-methylol (meth) acrylamide and dimethylol (meth) acrylamide; Monomers having functional groups such as monomers containing amino groups such as (meth) acrylate, dimethylaminoethyl (meth) acrylate and vinylpyridine; epoxy group-containing monomers such as allyl glycidyl ether and (meth) acrylic acid glycidyl ether It is below.
Examples of the monomer having an acid group forming an acrylic resin include monomers containing a carboxyl group such as (meth) acrylic acid, itaconic acid, crotonic acid, maleic acid, monobutyl maleate, and β-carboxyethyl acrylate. be able to.

The acrylic resin may have a repeating unit derived from a monomer having an aromatic hydrocarbon group and an alicyclic hydrocarbon group, and the acrylic resin may contain carbon and hydrogen having no lone pair. Since it has a structure that contains a large amount and suppresses moisture in the atmosphere from being adsorbed by the binder resin, it can prevent deterioration of the pigment contained in the binder resin due to moisture under high temperature and high humidity, and the binder. The bulkiness of the aromatic hydrocarbon group or alicyclic hydrocarbon group present in the resin is preferable because the dispersibility of the dye is improved and the reaction between the dyes can be suppressed.
Examples of the aromatic hydrocarbon contained in the aromatic hydrocarbon group introduced into the binder resin of the present invention include a benzene ring, a naphthalene ring, and an anthracene ring, and among them, a benzene ring is preferable. Specific examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, anthryl group, biphenyl group, benzyl group, triphenylmethyl group, tolyl group, xylyl group and the like.

Examples of the alicyclic hydrocarbon contained in the alicyclic hydrocarbon group introduced into the binder resin include a cyclopentane ring, a cyclohexane ring, a bicyclooctane ring, a tricyclodecane ring, a norbornene ring, and an adamantane ring. Of these, a tricyclodecane ring and a norbornene ring are preferable. Specific examples of the alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a bicyclooctyl group, a tricyclodecyl group, a norbornyl group, an adamantyl group, and the like.
A structure in which the aromatic hydrocarbon group or alicyclic hydrocarbon group introduced into the binder resin is pendant as a side chain in the main chain rather than being introduced into the main chain constituting the resin Is preferably introduced.
Here, a suitable example of a monomer having an aromatic hydrocarbon group and an alicyclic hydrocarbon group is represented by the following general formula (2). A repeating unit derived from a monomer having an aromatic hydrocarbon group and an alicyclic hydrocarbon group is represented by the following general formula (3).

（式（２）及び（３）において、Ｒ_１３は水素又は炭素数１〜３のアルキル基、Ｘは芳香族炭化水素基又は脂環式炭化水素基、Ｙは直接結合又は連結基である。）
Ｒ_１３は水素又はメチル基が好ましい。Ｙは直接結合か、あるいはメチレン基、エチレン基、エステル結合が好ましい。
式（２）の例としては、例えば下記に示す化学構造例が挙げられる。

(In the formulas (2) and (3), R ₁₃ is hydrogen or an alkyl group having 1 to 3 carbon atoms, X is an aromatic hydrocarbon group or alicyclic hydrocarbon group, and Y is a direct bond or linking group. )
R ₁₃ is preferably hydrogen or a methyl group. Y is preferably a direct bond, or a methylene group, an ethylene group or an ester bond.
Examples of the formula (2) include the following chemical structure examples.

  The aromatic hydrocarbon group or the alicyclic hydrocarbon group may have a substituent. For example, alkyl groups having 1 to 6 carbon atoms such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, s-butyl group, t-butyl group, pentyl group, hexyl group and the like are preferable. Furthermore, a C1-C4, especially C1-C2 alkyl group is preferable. The substituent may be substituted at any position in the aromatic hydrocarbon group or the alicyclic hydrocarbon group.

The acrylic resin contained in the display filter of the present invention comprises a polymer derived from a single acrylic monomer and / or a copolymer derived from a plurality of acrylic monomers. Co) polymers may be used singly or in combination, but styrene, methyl methacrylate, ethyl methacrylate combination, methyl methacrylate and butyl methacrylate combination, methyl methacrylate and methacrylic acid Combination of ethyl, combination of methyl methacrylate and methyl acrylate, combination of methyl methacrylate, cyclohexyl methacrylate and 2-ethylhexyl acrylate, combination of methyl methacrylate and tricyclodecyl methacrylate, methyl methacrylate and tricyclomethacrylate Decyl and ben methacrylate Or a copolymer used in combination of methyl methacrylate and isobonyl methacrylate is preferable from the viewpoint of improving the mechanical strength of the dye layer and improving the adhesion between the support substrate and the dye layer. .
The molecular weight of the acrylic resin is preferably 1,000 to 500,000, more preferably 10,000 to 100,000.
The total amount of the binder resin is preferably 40 to 99% by weight, more preferably 50 to 98% by weight, based on the solid content of the entire dye layer.

[Residual solvent]
Residual solvent content of the dye layer is in the range of 1-250 mg / ^{m 2.}
Here, the residual solvent amount in the dye layer means that the solvent for dissolving the binder resin and dispersing the dye and other additives contained in the dye layer forming composition described later is after the dye layer is formed. The remaining amount, specifically, a value quantified by the following measuring method. First, 22 strips of about 0.9 cm × 5 cm are prepared from a display filter cut into a 10 cm square, and packed into a 30 ml vial to prepare a measurement sample. Next, a gas chromatograph using (manufactured by Shimadzu Corporation, trade name "GC-9A"), 0.99 ° C. Samples for the measurement, 10 minutes, heated trap, determine the total amount of solvent, per 1 m ² In terms of weight, the value obtained is taken as the residual solvent amount.

  If the amount of residual solvent becomes too large, the apparent glass transition temperature of the binder resin decreases when left in a high temperature and high humidity condition for a long time, and the interaction between the residual solvent and the pigment, the interaction between the binder resin and the pigment, and different The near-infrared absorbing dye may be modified due to the interaction between the dyes. As a result, when the dye layer is incorporated in a display filter, absorption in the near infrared region of the filter may be reduced, and sufficient near infrared light may not be blocked. In addition, light transmittance in the visible region may decrease, absorption of a specific wavelength may appear in the visible region, and the filter may be colored.

In the range where the residual solvent amount exceeds 250 mg / m ² , the absorption in the near infrared region is reduced as described above, and it may be impossible to sufficiently block the near infrared ray. In addition, light transmittance in the visible region may decrease, absorption of a specific wavelength may appear in the visible region, and the filter may be colored. On the other hand, when the residual solvent amount is less than 1 mg / m ² , the modification of the near-infrared absorbing dye when left for a long time under high temperature and high humidity becomes small, but the thermal drying necessary to make it less than 1 mg / m ^2. Depending on the case, the near-infrared absorbing dye may be easily modified.
Moreover, the filter for displays which was further excellent in heat resistance can be obtained by making the amount of residual solvents in the said pigment layer into the range of 1-100 mg / m < ² >.

  The dye layer of the present invention can contain additives as required in addition to the binder resin and the dye described above. Further, an ultraviolet absorber may be contained to serve as an ultraviolet absorbing function.

  The ultraviolet absorber that can be used in the present invention shields or controls ultraviolet rays contained in electrical or electronic devices, natural light, and the like. This makes it possible to further improve the durability of various resin materials and other constituent materials (for example, a binder resin and a pigment) that constitute the display.

  Examples of the ultraviolet absorber include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-butylphenyl) benzotriazole, and 2- (2′-hydroxy). -5′-t-butylphenyl) benzotriazole, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-butyl) Phenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-amylphenyl) benzotriazole, 2- (2′-hydroxy-3′-t-butyl-5′-methylphenyl) Benzoto such as -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole Azole series; 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octyloxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone Benzophenone series such as 2,2′-dihydroxy-4,4′-dimethoxybenzophenone; salicylate series such as phenyl salicylate, pt-butylphenyl salicylate, p-octylphenyl salicylate; hexadecyl-2,5-t-butyl Organic ultraviolet absorbers such as benzoates such as -4-hydroxybenzoate, 2,4-di-t-butylphenyl-3 ′, 5′-di-t-butyl-4′-hydroxybenzoate, titanium oxide, Zinc oxide, cerium oxide, Iron, and inorganic ultraviolet absorbers such as barium sulfate.

When an ultraviolet absorber is used, the blending amount is preferably 0.5% by weight or more and less than 50% by weight with respect to the solid content of the entire dye layer. More preferably, it is 2 to 40% by weight, and particularly preferably 2 to 25% by weight.
As other additives, conventionally known additives generally used in resin compositions for forming films, coating films and the like can be used. For example, leveling agents, antifoaming agents, anti-sagging agents, oxidation agents, etc. Examples thereof include an inhibitor, a viscosity modifier, a metal deactivator, a peroxide decomposing agent, a plasticizer, and an antistatic agent.

  The dye layer of the present invention can be formed by any desired method, but in order to prevent deterioration of the dye and the binder resin, no harmful components that cause deterioration of the dye or the binder resin are used, Or it is preferable to form by the method of using little amount and not requiring excessive temperature and pressure. As one of such methods, for example, a dye layer forming resin composition in which a dye and a binder resin are dissolved in an organic solvent, or a dye is added to a resin wetted with a solvent and sufficiently dispersed. A method of laminating the resin composition for forming a dye layer on a supporting substrate described later and drying it is mentioned.

  The solvent used for dissolving the binder resin and dispersing or wetting the pigment and other additives is not particularly limited as long as it can uniformly dissolve or disperse the pigment and binder resin. For example, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, propyl acetate, benzene, toluene, xylene, methanol, ethanol, isopropanol, chloroform, methylene chloride, tetrahydrofuran, N, N-dimethylformamide, acetonitrile, trifluoropropanol, n- Although hexane, n-heptane, water, etc. are mentioned, things other than these may be sufficient.

As a method of laminating the dye layer forming composition on the support substrate, coating, for example, dipping, spraying, brush coating, Mayer bar coating, doctor blade coating, gravure coating, gravure reverse coating, kiss reverse coating, three rolls Various coating methods such as reverse coating, slit reverse die coating, die coating, or comma coating can be used.
The coating film obtained by the above method is evaporated with hot air so that the residual solvent amount in the pigment layer is in the range of 1 to 250 mg / m ² and dried to obtain the pigment layer of the present invention. In order to reduce the residual solvent amount in the dye layer to 250 mg / m ² or less and prevent deterioration of the dye layer due to drying, the drying conditions are: wind speed 1-50 m / second, hot air temperature 50-150 ° C., drying time 40 seconds- It is preferable to select and combine them appropriately from the condition of 5 minutes.
Further, if necessary, the dried coating film may be cured by heat, electron beam or the like.

  The thickness of the dye layer is not particularly limited as long as it is appropriately set depending on the intended use. For example, it is preferable to set the thickness at the time of drying to 0.5 to 1000 μm. More preferably, it is 1-100 micrometers. More preferably, it is 1-50 micrometers, Most preferably, it is 1-30 micrometers.

When a display filter is applied to the front surface of a plasma display panel, which is a typical application, a dye layer containing a near-infrared absorbing dye is a near-infrared ray that is generated when the plasma display panel emits light using xenon gas discharge. It absorbs a region, that is, a wavelength region of 800 nm to 1100 nm, and the near infrared transmittance of the band is preferably 20% or less, more preferably 15% or less.
Also, the dye layer containing the neon light absorbing dye is neon light emitted when the plasma display panel emits light using xenon gas discharge, when neon atoms are excited and then returns to the ground state, that is, 570. It absorbs a wavelength region of ˜610 nm, and the transmittance of the band is preferably 50% or less, more preferably 40% or less.
At the same time, it is desirable that the dye layer has a sufficient light transmittance, that is, a luminous transmittance of 30% or more in a visible light region, that is, a wavelength region of 380 nm to 780 nm.

  In the display filter of the present invention, the dye layer may be two or more layers instead of one layer. For example, the diimmonium compound represented by the above formula (1), other near-infrared absorbing dyes, neon light absorbing dyes or color tone adjusting dyes can be mixed and contained in one dye layer, Independent layers contained separately, that is, a near-infrared absorbing functional layer, a neon light absorbing functional layer, or a color tone adjusting functional layer may be laminated and provided.

[Supporting substrate]
The support substrate used in the display filter of the present invention is not particularly limited as long as a dye layer can be laminated. For example, polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), cyclic polyolefin, polyethylene Films made of polyolefins such as polypropylene and polystyrene, vinyl resins such as polyvinyl chloride and polyvinylidene chloride, resins such as polycarbonate, acrylic resin, triacetyl cellulose (TAC), polyether sulfone, or polyether ketone These can be used alone, or the same kind or different kinds can be laminated. As the support substrate used in the display filter of the present invention, PET, TAC, and acrylic resin are particularly preferable from the viewpoint of transparency.

  Regarding the transparency of the supporting substrate, when the supporting substrate is a single layer, the light transmittance in the visible region is preferably 80% or more. Further, having transparency is preferably colorless and transparent, but is not necessarily colorless and transparent, and may be colored and transparent as long as the object of the present invention is not hindered. Although the light transmittance in the visible region is preferably as high as possible, the final product needs to have a light transmittance in the visible region of 50% or more. A substrate having a light transmittance of 80% is suitable for the purpose. Since the higher the light transmittance is, the more the supporting substrate can be laminated, the light transmittance of the single layer of the supporting substrate is more preferably 85% or more, and most preferably 90% or more. Reducing the thickness is also an effective means for improving the light transmittance.

The thickness of the supporting substrate is not particularly limited as long as the transparency is satisfied, but it is preferably in the range of about 12 μm to 300 μm from the viewpoint of workability. When the thickness is less than 12 μm, the supporting substrate is too flexible, and stretching and wrinkles are likely to occur due to the tension during processing. In addition, when the thickness exceeds 300 μm, the flexibility of the film is reduced, and continuous winding in each process becomes difficult, and the workability when laminating a plurality of support substrates is greatly deteriorated. There is also.
Since the display layer filter of the present invention has sufficient adhesion to the support substrate, the support substrate used in the present invention does not require a surface treatment to improve the adhesion, and is not yet treated. It may be a base material, and as another surface treatment, for example, a surface treatment for the purpose of controlling the refractive index or preventing charging may be performed.

[Electromagnetic wave shielding functional layer]
In the display filter of the present invention, the electromagnetic wave shielding functional layer that can be added as a functional layer to the dye layer or the laminate thereof shields electromagnetic waves generated from an electrical or electronic device, particularly a plasma display. As the electromagnetic wave shielding layer, a metal mesh layer and a transparent conductive thin film layer are used, and a metal mesh having high electromagnetic wave shielding properties is preferable. Since the metal mesh layer is formed by laminating a metal foil on a supporting base material and forming a mesh shape by etching, an adhesive layer is usually interposed between the supporting base material and the metal mesh. Adhesive layer is acrylic resin, polyester resin, polyurethane resin, polyvinyl alcohol alone or saponified product thereof, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, polyimide resin, epoxy resin, polyurethane ester It is composed of an adhesive such as resin. The metal mesh layer is not particularly limited as long as it has an electromagnetic wave shielding function. For example, copper, iron, nickel, chromium, aluminum, gold, silver, stainless steel, tungsten, chromium, Titanium or the like can be used, and copper is particularly preferable. Examples of the copper foil include rolled copper foil and electrolytic copper foil, and the electrolytic copper foil is particularly preferable. By selecting the electrolytic copper foil, it is possible to achieve a good uniformity with a thickness of 10 μm or less, and good adhesion to chromium oxide etc. when blackened. Because you can.

  Here, in this invention, it is preferable that the one side or both surfaces of the said metal mesh are blackened. The blackening treatment is a treatment for blackening the surface of the metal mesh with chromium oxide or the like, and when applied to the dye layer or a laminate thereof, this oxidation treatment surface is usually the surface on the observer side. Placed in. Since the external light on the surface of the metal mesh layer is absorbed by chromium oxide or the like formed on the surface of the metal mesh layer by the blackening treatment, it is possible to prevent light from being scattered on the surface of the metal mesh layer.

The aperture ratio of the metal mesh layer is preferably as low as possible from the viewpoint of electromagnetic wave shielding ability. However, since the light transmittance decreases as the aperture ratio decreases, the aperture ratio is preferably 50% or more.
Moreover, since the opening part and non-opening part of a metal mesh layer are uneven | corrugated, the planarization layer in which binder resin was formed in the thickness more than the thickness of a metal mesh layer is laminated | stacked on the metal mesh layer. Also good.

[Anti-reflective function layer]
In the display filter of the present invention, the antireflection functional layer that can be added to the dye layer or a laminate thereof is typically a laminate of a combination of a high refractive index layer and a low refractive index layer. It may have a layer structure other than this as long as it has a function. The high refractive index layer is, for example, a thin film of ZnO or TiO ₂ material, or a transparent binder resin film in which fine particles of these materials are dispersed. Further, the low refractive index layer, a thin film made of SiO ₂ or SiO ₂ gel film, or a fluorine-containing or fluorine and a binder resin film having transparency of the silicon-containing. When the antireflection layer is laminated on the display filter of the present invention, it is possible to reduce reflection of unnecessary light such as external light on the laminated side, and to increase the contrast of the image or video of the applied display. it can.

[Anti-glare functional layer]
In the display filter of the present invention, the antiglare function layer that can be added to the dye layer or the laminate thereof is, for example, dispersed beads such as polystyrene resin or acrylic resin having a diameter of about several μm in a transparent binder resin. Can be mentioned. This is for preventing scintillation occurring at a specific position and direction of the display when it is arranged on the front surface of the display due to the light spreading property of the layer.

[Contamination prevention function layer]
In the display filter of the present invention, the antifouling functional layer that can be added to the display filter is caused by inadvertent contact or environmental contamination on the surface of the dye layer or a laminate thereof. It is a layer formed to prevent dust and contaminants from adhering, or to facilitate removal even if they adhere. For example, a fluorine-based coating resin, a silicon-based coating agent, a silicon / fluorine-based coating agent, or the like is used, and among them, a silicon / fluorine-based coating agent is preferably applied. The thickness of these antifouling layers is preferably 100 nm or less, more preferably 10 nm or less, and even more preferably 5 nm or less. When the thickness of these antifouling layers exceeds 100 nm, the initial value of antifouling properties is excellent, but the durability is inferior. 5 nm or less is the most preferable from the balance of antifouling property and its durability.

[Ultraviolet absorbing functional layer]
In addition, in the display filter of the present invention, an independent layer containing an ultraviolet absorber, that is, an ultraviolet absorbing functional layer may be further provided.
In the case of an independent ultraviolet absorption functional layer, instead of providing a layer containing the ultraviolet absorber, a commercially available ultraviolet cut filter, for example, “Sharp Cut Filter SC-38” (trade name, manufactured by Fuji Photo Film Co., Ltd.) ), “Same SC-39”, “Same SC-40”, “Acryprene” (trade name) manufactured by Mitsubishi Rayon Co., Ltd., and the like.

The display filter of the present invention obtained as described above is generated when the plasma display panel emits light using xenon gas discharge when applied to the front surface of the plasma display panel which is a typical application. The light transmittance in the near infrared region, that is, in the wavelength region of 800 to 1100 nm is preferably 20% or less, and more preferably 15% or less.
In addition, when the display filter of the present invention includes a dye layer containing a neon light absorbing dye, when the plasma display panel emits light using xenon gas discharge, the neon atoms are excited, The neon light emitted when returning to the state, that is, the light transmittance in the wavelength region of 570 to 610 nm is preferably 50% or less, more preferably 40% or less.
The display filter of the present invention desirably has a sufficient light transmittance, that is, a luminous transmittance of 30% or more in the visible light region, that is, in the wavelength region of 380 to 780 nm.

  The display filter of the present invention has excellent heat resistance, and changes in spectral characteristics attributed to dye deterioration hardly occur even when used for a long time under high temperature and high humidity. Specifically, when the heat and humidity resistance test is performed as follows, the value of the light transmittance at a wavelength at which the difference in the light transmittance value at each wavelength before and after being left in a high-temperature and high-humidity atmosphere is maximized. The difference is desirably 5% or less, more preferably 4% or less.

First, the light transmittance of the display filter of the present invention is determined. The light transmittance of the display filter is measured in the wavelength range of 800 to 1100 nm. The light transmittance can be measured using, for example, a spectrophotometer (manufactured by Shimadzu Corporation, product number: “UV-3100PC”).
Next, the obtained display filter is left in a high-temperature and high-humidity (for example, temperature 60 ° C., humidity 90% RH) atmosphere for 1000 hours, and then the light transmittance is measured in the same wavelength range as described above.
From the measured value of the light transmittance at each wavelength before and after being left in the high temperature and high humidity atmosphere, the difference in the light transmittance at each wavelength is obtained, and the difference in the light transmittance at the wavelength at which the value is maximum is obtained. .

  In addition, the display filter of the present invention has excellent adhesion to a supporting substrate. Specifically, when the adhesiveness of the interface between the dye layer of the obtained display filter and the support substrate was evaluated according to the cross-cut tape method described in JIS K5400, the evaluation score was 8 or more (the cut It is desirable that there is slight peeling at the intersection, no peeling at a glance of the square, and the area of the defect is within 5% of the total square area).

Next, the display of the present invention is characterized in that the display filter is arranged on the display surface of the display.
Examples of the display of the present invention include electronic displays such as CRT (CRT), LCD (Liquid Crystal Display), PDP (Plasma Display), organic / inorganic EL display, and FED (Field Emission Display), which are display panels of various electronic devices. Is mentioned.

  As shown in FIG. 2, when the display filter 11 according to the present invention is used in the display 7 of the present invention, for example, unwanted light such as near infrared rays emitted from the display panel 6 or electromagnetic waves are cut off. Therefore, it is installed in front of the display panel display surface 8.

The evaluation method performed in the Example mentioned later is as follows.
(1) Heat resistance of display filter Using a spectrophotometer (manufactured by Shimadzu Corporation, product number: "UV-3100PC"), the light transmittance of the display filter was measured in the range of 800 to 1100 nm.
The obtained display filter was left in a high temperature and high humidity (temperature 60 ° C., humidity 90% RH) atmosphere for 1000 hours, and then the light transmittance was measured in the same wavelength range as described above.
The difference in the light transmittance value at the wavelength where the maximum light transmittance in the initial state is 10% or less and the difference in the light transmittance value of each wavelength before and after being left in a high temperature and high humidity atmosphere is the maximum. Is 5% or less, the dye deterioration of the display filter is acceptable.
In addition, as for the filter for displays containing the near-infrared absorptive pigment | dye of the following Examples 1-6 and Comparative Examples 1-4, all have the wavelength from which the difference of the value of light transmittance shows the maximum value in the range of 800-1100 nm. It was 1080 nm.

(2) Glass transition temperature The glass transition temperature was measured according to JIS K7121 using a differential scanning calorimeter (manufactured by NETZSCH, trade name DSC204 Phoenix). The measurement method was DSC method, the measurement start temperature was 20 ° C., the measurement end temperature was 220 ° C., the temperature raising and cooling rates were 2 ° C./min, and a nitrogen atmosphere. Further, the glass transition temperature here is the temperature at the point where the straight line equidistant in the vertical axis direction from the extended straight line of each base line and the curve of the step-like change part of the glass transition, that is, the midpoint glass. Refers to the transition temperature.

(3) Residual solvent amount First, 22 strips of about 0.9 cm × 5 cm were prepared from a sample cut into a 10 cm square, and packed into a 30 ml vial to prepare a measurement sample. Next, using a gas chromatograph (manufactured by Shimadzu Corporation, trade name "GC-9A"), the sample for measurement of 120 ° C., 10 minutes, heated trap, determine the total amount of toluene and methyl ethyl ketone, 1 m ² Converted to the amount per unit.

(4) Adhesiveness After the obtained display filter was allowed to stand for 1000 hours in an atmosphere at a temperature of 60 ° C. and a humidity of 90% RH, the dye for the obtained display filter was obtained according to the cross-cut tape method described in JIS K5400. Evaluate the adhesion of the interface between the layer and the support substrate, and the evaluation score is 8 or more (there is slight peeling at the intersection of the cuts, there is no peeling at a glance of the square, and the area of the defect part is the total square area) (Within 5%) was set as an allowable range.

  Hereinafter, the present invention will be described more specifically with reference to examples. These descriptions do not limit the present invention. In the examples, parts represent parts by weight unless otherwise specified.

<Example 1>
Dianal BR-113 (Mitsubishi Rayon Co., Ltd., glass transition temperature = 75 ° C., acid value = 3, hydroxyl value = 0) as binder resin in methyl ethyl ketone / toluene (solvent blend ratio = 1: 1) A near-infrared absorbing dye (Nippon Kayaku Co., Ltd., trade name: IRG-022, R _{1 to} R _{8 in the} above formula (1) in 19.6 g of the resin solution dissolved so that the ratio becomes 20% (mass basis) Is a n-butyl group, X ^- is a coating film obtained by adding 0.2 g of hexafluoroantimony ion) and sufficiently dispersing it on a commercially available PET film with a Meyer bar. Was applied to a dry air with a wind speed of 5 m / sec and dried at 130 ° C. for 1 minute to form a near-infrared absorbing layer to obtain a display filter. The residual solvent amount was 35 mg / m ² .

The obtained display filter had a light transmittance of 1080% at 1080 nm, and was allowed to stand in an atmosphere at a temperature of 60 ° C. and a humidity of 90% RH for 1000 hours. As a result, the light transmittance at 1080 nm was 5.5%. It became. From the above, the difference in the value of light transmittance at 1080 nm, which was the maximum value of the difference in light transmittance value at 800 to 1100 nm, was 1.4%.
Further, the cross tape method described in JIS K5400 is used to determine the adhesion between the near-infrared absorbing layer of a display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as a supporting substrate. As a result of evaluation according to the above, there was no peeling at a glance, and sufficient adhesion was shown.

<Example 2>
A display filter was obtained in the same manner as in Example 1 except that the drying conditions were 110 ° C. and 1 minute. The residual solvent amount was 87 mg / m ² .
The obtained display filter had a light transmittance of 1080% at 1080 nm, and was allowed to stand in an atmosphere at a temperature of 60 ° C. and a humidity of 90% RH for 1000 hours. As a result, the light transmittance at 1080 nm was 6.5%. It became. From the above, the difference in the value of light transmittance at 1080 nm, which was the maximum value of the difference in light transmittance value at 800 to 1100 nm, was 2.2%.
Further, the cross tape method described in JIS K5400 is used to determine the adhesion between the near-infrared absorbing layer of a display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as a supporting substrate. As a result of evaluation according to the above, there was no peeling at a glance, and sufficient adhesion was shown.

<Example 3>
A display filter was obtained in the same manner as in Example 1 except that the drying conditions were 110 ° C. and 40 seconds. The residual solvent amount was 221 mg / m ² .
The obtained display filter had a light transmittance of 1080% at 1080 nm, and was left for 1000 hours in an atmosphere at a temperature of 60 ° C. and a humidity of 90% RH. As a result, the light transmittance at 1080 nm was 7.3%. It became. From the above, the difference in light transmittance at 1080 nm, which was the maximum value difference in light transmittance at 800 to 1100 nm, was 3.0%.
Further, the cross tape method described in JIS K5400 is used to determine the adhesion between the near-infrared absorbing layer of a display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as a supporting substrate. As a result of evaluation according to the above, there was no peeling at a glance, and sufficient adhesion was shown.

<Example 4>
As a near-infrared absorbing dye, instead of IRG-022, IRG-068 (Nippon Kayaku Co., Ltd., R _{1 to} R ₈ of the formula (1) as an iso-butyl group which is a branched alkyl group, A display filter was obtained in the same manner as in Example 1 except that X ⁻ was bistrifluoromethanesulfonylimido ion). The residual solvent amount was 43 mg / m ² .
The light transmittance at 1080 nm of the obtained display filter is 4.1%, and the light transmittance at 1080 nm is 4.5% as a result of leaving it in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH for 1000 hours. It became. From the above, the difference in the value of light transmittance at 1080 nm, which was the maximum value difference in the value of light transmittance at 800 to 1100 nm, was 0.4%.
Further, the cross tape method described in JIS K5400 is used to determine the adhesion between the near-infrared absorbing layer of a display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as a supporting substrate. As a result of evaluation according to the above, there was no peeling at a glance, and sufficient adhesion was shown.

<Example 5>
A display filter was obtained in the same manner as in Example 1 except that 0.01 g of neon light absorbing dye TY102 (Asahi Denka Co., Ltd.) was further added as a dye. The residual solvent amount was 33 mg / m ² .
The light transmittance at 1080 nm of the obtained display filter is 4.0%, and the light transmittance at 1080 nm is 5.5% as a result of leaving it in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH for 1000 hours. It became. From the above, the difference in light transmittance value at 1080 nm, which was the maximum value difference in light transmittance values at 800 to 1100 nm, was 1.5%.
Further, the cross tape method described in JIS K5400 is used to determine the adhesion between the near-infrared absorbing layer of a display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as a supporting substrate. As a result of evaluation according to the above, there was no peeling at a glance, and sufficient adhesion was shown.

<Example 6>
As a binder resin, acrylic resin Dianal BR-80 (manufactured by Mitsubishi Rayon Co., Ltd., glass transition temperature = 105 ° C., acid value = 0, hydroxyl group = 0) and dialnal BR-87 (manufactured by Mitsubishi Rayon Co., Ltd.) The same procedure as in Example 1 was conducted except that a resin (acid value = 7.4) in which glass transition temperature = 105 ° C., acid value = 10.5, and hydroxyl value = 0) were mixed at a ratio of 3 to 7 was used. A display filter was obtained. The residual solvent was 55 mg / ^{m 2.}
The obtained display filter has a light transmittance of 1080% at 1080 nm, and is left for 1000 hours in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH. As a result, the light transmittance at 1080 nm is 8.2%. It became. From the above, the difference in the light transmittance value at 1080 nm, which was the maximum value difference in the light transmittance value at 800 to 1100 nm, was 3.7%.
Further, the cross tape method described in JIS K5400 is used to determine the adhesion between the near-infrared absorbing layer of a display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as a supporting substrate. As a result of evaluation according to the above, there was no peeling at a glance, and sufficient adhesion was shown.

<Comparative Example 1>
A display filter was obtained in the same manner as in Example 1 except that the drying conditions were 60 ° C. and 20 seconds. The residual solvent amount was 354 mg / m ² .
The obtained display filter had a light transmittance of 1080% at 1080 nm, and was left for 1000 hours in an atmosphere at a temperature of 60 ° C. and a humidity of 90% RH. As a result, the light transmittance at 1080 nm was 9.5%. It became. From the above, the difference in the value of light transmittance at 1080 nm, which was the maximum difference in the value of light transmittance at 800 to 1100 nm, was 5.2%, and a decrease in near infrared absorption ability was observed.
Further, the cross tape method described in JIS K5400 is used to determine the adhesion between the near-infrared absorbing layer of a display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as a supporting substrate. As a result of evaluation according to the above, there was no peeling at a glance, and sufficient adhesion was shown.

<Comparative example 2>
A display filter was obtained in the same manner as in Example 1 except that the drying conditions were 150 ° C. and 10 minutes. The residual solvent amount was 0.6 mg / m ² .
The obtained display filter had a light transmittance at 1080 nm of 12.5%, which was inferior in near-infrared absorptivity before the heat resistance test. As a result of leaving this in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH for 1000 hours, the light transmittance at 1080 nm was 12.9%. From the above, the difference in the value of light transmittance at 1080 nm, which was the maximum value difference in the value of light transmittance at 800 to 1100 nm, was 0.4%.
Further, the cross tape method described in JIS K5400 is used to determine the adhesion between the near-infrared absorbing layer of a display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as a supporting substrate. As a result of evaluation according to the above, there was no peeling at a glance, and sufficient adhesion was shown.

<Comparative Example 3>
The filter for display was carried out in the same manner as in Example 1 except that Dianal BR-77 (manufactured by Mitsubishi Rayon Co., Ltd., glass transition temperature = 80 ° C., acid value = 18.5) was used as the binder resin. Got. The residual solvent amount was 46 mg / m ² .
The light transmittance at 1080 nm of the obtained display filter is 4.1%, and the light transmittance at 1080 nm is 12.9% as a result of leaving it in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH for 1000 hours. It became. From the above, the difference in the value of light transmittance at 1080 nm, which was the maximum difference in the value of light transmittance at 800 to 1100 nm, was 8.8%, and a decrease in near infrared absorption ability was observed.
Further, the cross tape method described in JIS K5400 is used to determine the adhesion between the near-infrared absorbing layer of a display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as a supporting substrate. As a result of evaluation according to the above, there was no peeling at a glance, and sufficient adhesion was shown.

<Comparative example 4>
Optretz OZ-1100 (manufactured by Hitachi Chemical Co., Ltd., acid value = 0, hydroxyl group value = 0, glass transition temperature = 120 ° C.) and dialnal BR-83 (manufactured by Mitsubishi Rayon Co., Ltd., glass transition temperature) as binder resins = 105 ° C, acid value = 2, hydroxyl value = 0) is used in the same manner as in Example 1 except that a resin (acid value = 0.04) mixed at a ratio of 50 to 1 is used. A filter was obtained. The residual solvent was 59 mg / ^{m 2.}
The obtained display filter had a light transmittance of 1080% at 1080 nm, and was allowed to stand in an atmosphere at a temperature of 60 ° C. and a humidity of 90% RH for 1000 hours. As a result, the light transmittance at 1080 nm was 5.2%. It became. From the above, the difference in light transmittance value at 1080 nm, which was the maximum value difference in light transmittance values at 800 to 1100 nm, was 1.2%.
However, the cross-cut tape method described in JIS K5400 indicates the adhesion between the near-infrared absorbing layer of the display filter obtained by leaving it in an atmosphere of 60 ° C. and humidity 90% RH for 1000 hours and PET as the supporting substrate. As a result of evaluation according to, the ratio of peeling to the evaluation area was 65% or more, indicating poor adhesion.

<Summary of results>
In the display filters obtained in Examples 1 to 6, the maximum difference in the light transmittance values before and after being left in a high-temperature and high-humidity atmosphere for 1000 hours is within an allowable range, and the spectral characteristics attributed to dye deterioration. The stability of changes was excellent. Moreover, it had sufficient adhesiveness between the near-infrared absorption layer or neon light absorption layer of the display filter left in a high-temperature and high-humidity atmosphere for 1000 hours and PET as the supporting substrate.

On the other hand, the display filter obtained in Comparative Example 1 in which the residual solvent amount of the binder resin is larger than the range of the present invention has sufficient adhesion, but has a near infrared absorption ability after being left in a high temperature and high humidity atmosphere. A decrease was observed.
Further, the display filter obtained in Comparative Example 2 in which the residual solvent amount of the binder resin is smaller than the range of the present invention was sufficient in adhesion, but the near-infrared absorption ability decreased before the heat resistance test. Was recognized.
In addition, the display filter obtained in Comparative Example 3 in which the acid value of the binder resin is larger than the range of the present invention has sufficient adhesion, but the near-infrared absorption ability after being left in a high-temperature and high-humidity atmosphere is reduced. Was recognized.
Further, the display filter obtained in Comparative Example 4 having an acid value of 0 had a change in spectral characteristics within an allowable range, but resulted in insufficient adhesion.

It is a schematic sectional drawing which shows an example of the filter for displays of this invention. It is a schematic sectional drawing which shows an example of the display formed by arrange | positioning the display filter of this invention, and this display filter on the display surface. It is a schematic sectional drawing which shows an example of the filter for displays of this invention. It is a schematic sectional drawing which shows an example of the filter for displays of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Display filter 2 Support base material 3 Dye layer 4 Laminated body 5 Functional layer 5 'Functional layer 6 Display panel 7 Display 8 Display panel display surface 11 Display filter

Claims (9)

A display filter having a laminated structure in which at least a support base material and a dye layer containing a binder resin and a dye are laminated, the dye containing at least a diimmonium compound represented by the following formula (1), The binder resin has a glass transition temperature of 65 to 140 ° C., an acid value of 0.1 to 10, and a residual solvent amount in the dye layer in the range of 1 to 250 mg / m ² . filter.

(Wherein R _{1 to} R ₈ represent a hydrogen atom, an alkyl group, an aryl group, an alkenyl group, an aralkyl group, or an alkynyl group, and may be the same or different. R _{9 to} R ₁₂ It represents a hydrogen atom, a halogen atom, an amino group, a cyano group, a nitro group, a carboxyl group, an alkyl group, or alkoxy group, even each same may be different .R ₁ to R ₁₂ substituents May be substituted, and X ⁻ represents an anion.)   The display filter according to claim 1, wherein the binder resin has a hydroxyl value of 10 or less. The display filter according to claim 1, wherein at least one of R _{1 to} R ₈ in the formula (1) is a branched alkyl group. The display filter according to claim 1, wherein the anion X ⁻ in the diimmonium compound represented by the formula (1) is a sulfonylimide acid ion.   5. The display filter according to claim 1, wherein the display filter has an absorption maximum of light transmittance at least from 570 to 610 nm.   6. The display filter according to claim 1, wherein the display filter has an absorption maximum of light transmittance at least at a wavelength of 380 to 570 nm or 610 to 780 nm.   The display filter according to claim 1, wherein the binder resin contains an ultraviolet absorber.   8. The display filter according to claim 1, wherein the display filter has one or more of an electromagnetic wave shielding function, an antireflection function, an antiglare function, an antifouling function, and an ultraviolet absorption function. Alternatively, a display filter comprising two or more layers.   9. A display comprising the display filter according to claim 1 disposed on a display surface of the display.

Images