JP2006047801A - Thermal bonding film for color correction, and near ir ray cut-off filter with thermal bonding function using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal bonding film for color correction which does not require aging and can deal with various colors at a low cost, and an IR ray cut-off filter with a thermal bonding function using the same. <P>SOLUTION: The thermal bonding film for color correction is formed of a thermoplastic transparent resin containing a correction dyestuff having a Vicat softening point of 30 to 150°C, having the maximum absorption wavelength at 380 to 780 nm and having a mass light absorption coefficient of the maximum absorption wavelength of ≥10 mL/g so as to have a thickness of 50 to 200 μm by a solution casting method, and the IR ray cut-off filter with the thermal bonding function is formed by laminating the thermal bonding film for color correction and the IR ray cut-off filter, wherein the average ray transmittance within a range of a wavelength 380 to 780 nm is ≥40% and the average ray transmittance within a range of a wavelength 850 to 1,100 nm is ≤20%. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a color correction heat welding film and a near-infrared cut filter with a heat welding function using the same, and more particularly, color correction heat that does not require aging and can cope with various colors at low cost. The present invention relates to a welding film and a near-infrared cut filter having a heat welding function using the same.

Recently, a plasma display panel (PDP), which is a light-emitting type and a flat type display panel, has attracted attention as a large-sized display panel with excellent visibility.
In this PDP, near infrared rays derived from light emission of an inert gas such as Ne gas or Xe gas in the screen cell are emitted. The wavelength of the near infrared rays is the operating wavelength of the remote control device of various home appliances. It causes a malfunction.

Therefore, the optical filter installed on the front surface of such a PDP has excellent transparency (light transmittance), good visibility and a wide viewing angle, and has a near-infrared cut function. It is requested.
Further, in addition to the above functions, the PDP optical filter is required to have a color correction (color matching) function for reducing unnecessary light emitted by the PDP and improving the color purity and contrast of the emitted color.

Conventionally, color correction by an optical filter for PDP has been performed by blending a light-absorbing agent for color correction into an adhesive layer or a near-infrared cut layer to provide a color correction function (for example, Patent Document 1). -4 reference).
However, in the case of the pressure-sensitive adhesive layer, aging for about one week is necessary after blending the light absorber, and it takes a very long time for the production process, and it may be discolored by heat or moisture. This tends to occur when dyes are used.
On the other hand, in the case of a near-infrared cut layer, unlike multi-layer color matching, it is a single layer, so the color to be corrected is determined to be one color and cannot be diverted to other colors. Even if it is going to be lowered by mass production, if the color is fixed, only items of that color can be made, resulting in high costs. Furthermore, when color correction is performed with the near-infrared cut layer, discoloration may occur due to heat or moisture unless compatibility with other pigments is taken into consideration.

JP 2000-147245 A JP 2004-29436 A JP 2004-69931 A JP 2004-14538 A

  Thus, in view of the above-described background art, the present invention provides a color correction heat welding film that does not require aging and can cope with various colors at low cost, and a near infrared cut filter with a heat welding function using the same. It is intended to provide.

  As a result of intensive studies to solve the above problems, the present inventors have formed a specific thickness from a thermoplastic transparent resin having a specific Picat softening point and containing a color correction dye by a solution casting method. It has been found that the above-mentioned problems can be solved by using a heat-adhesive film for color correction characterized by the above. The present invention has been completed based on such findings.

That is, the present invention
(1) Thermoplastic transparent resin containing a color correction dye having a Picat softening point of 30 to 150 ° C., a maximum absorption wavelength at 380 to 780 nm, and a mass absorption coefficient of 10 mL / g · cm or more at the maximum absorption wavelength A heat-adhesive film for color correction, which is formed from 5 to 200 μm in thickness by a solution casting method,
(2) The heat-adhesive film for color correction according to (1), wherein the thermoplastic transparent resin is an acrylic resin, a polyester resin, a polyvinyl butyral resin, or an ethylene-vinyl acetate copolymer resin,
(3) The heat correction film for color correction of (1) or (2) above and a near infrared cut film are laminated, and the average light transmittance in the wavelength range of 380 to 780 nm is 40% or more, and the wavelength is 850. A near-infrared cut filter with a heat welding function, wherein the average light transmittance in a range of ˜1100 nm is 20% or less,
Is to provide.

The heat correction film for color correction of the present invention does not require aging, and can cope with various colors at low cost.
In general color matching, pigment-type color materials are used to ensure durability. However, color matching using this heat-welded layer is highly durable against dyes that are sensitive to heat and moisture. The range of color materials that can be used can be greatly expanded.

In the heat correction film for color correction of the present invention, a thermoplastic transparent resin having a Picat softening point of 30 to 150 ° C. is used.
The Picat softening point needs to be 30 to 150 ° C. in order to avoid melting during handling and to facilitate thermal welding.
Further, for the purpose of a display filter, the heat-welded resin layer after heat-welding needs to be transparent, and in particular, the haze measured by the method defined in JIS K7136 is 1.00% or less. preferable.
As the thermoplastic transparent resin that satisfies such requirements, resins that are usually used as hot-melt adhesives can be used. From the viewpoint of transparency after heat welding, acrylic resin, polyester resin, polyvinyl butyral resin are particularly preferable. And ethylene vinyl acetate copolymer resins are preferred.

The color correction pigment used in the heat correction film for color correction of the present invention is a pigment having a maximum absorption wavelength at 380 to 780 nm and a mass absorption coefficient of 10 mL / g · cm or more at the maximum absorption wavelength. Examples thereof include pigments, squarylium dyes, azomethine dyes, xanthene dyes, oxonol dyes and azo dyes.
If the mass absorption coefficient of the maximum absorption wavelength of the color correction dye is less than 10 mL / g · cm, the amount of addition becomes enormous for obtaining a predetermined color correction effect. Therefore, haze increases or the color correction dye bleeds out. End up.
As for the marketed products, Kayaset Blue N (maximum absorption wavelength 644 nm, mass extinction coefficient 54000 mL / g · cm), Kayaset Red B (maximum absorption wavelength 520 nm, mass extinction coefficient 44000 mL / g · manufactured by Nippon Kayaku Co., Ltd.) cm), Kayaset Violet AR (maximum absorption wavelength 558 nm, mass extinction coefficient 31000 mL / g · cm).

The heat correction film for color correction of the present invention is formed from a resin solution containing a color correction dye and a thermoplastic transparent resin to a thickness of 5 to 200 μm by a solution casting method.
In order to be a film with little unevenness, the film needs to be formed by a solution casting method. For example, a film formed by an extrusion molding method does not have little unevenness.
Further, the thickness needs to be 5 to 200 μm in order to perform adhesion without hindrance and to prevent unevenness in the adhesion. A preferred thickness is 6 to 50 μm.

The blending amount of the color correction dye is a unit area of the heat correction film for color correction, that is, 0.05 mg to 800 mg per m ² , preferably 0.08 mg to 600 mg per m ² , more preferably 0.1 mg to 1 mg per m ^2. A range of 400 mg is appropriate.
If the blending amount is less than the above range, the desired absorption capacity may not be obtained, and if it exceeds the above range, the visible light transmittance may decrease.

  The heat-adhesive film for color correction of the present invention is formed on a suitable release film by a solution casting method before use, and specifically, a thermoplastic transparent resin containing a color correction dye Is dispersed or dissolved in a solvent to obtain a solution having an appropriate solid content concentration, coated on an appropriate release film, and dried.

  The solvent used is not particularly limited as long as it can dissolve or disperse the color correction dye and the resin, and examples thereof include tetrahydrofuran (THF), diethyl ether, 1,4-dioxane, 1,3-dioxolane and the like. Ether solvents; ester solvents such as ethyl acetate, methyl acetate and butyl acetate; alcohol solvents such as methanol, ethanol and isopropyl alcohol; chlorine solvents such as chloroform and methylene chloride; dimethylformamide (DMF) and dimethyl sulfoxide An aprotic polar solvent such as (DMSO) or N-methylpyrrolidone (NMP); a ketone solvent such as acetone or methyl ethyl ketone (MEK), or a single solvent such as water, or a mixed solvent is preferably used.

  Examples of the coating method include coating methods such as brush coating, spray coating, dip coating, roll coating, calendar coating, spin coating, bar coating, gravure coating, die coating, and screen printing.

  The heat-adhesive film for color correction of the present invention is used for various display films such as PDP, for example, an electromagnetic shielding film, an antireflection film, an antiglare (AG) film, a hard coat film, an antifouling layer film, Although it can be heat-welded with a near-infrared cut film or the like and laminated, it is particularly useful to be laminated with a near-infrared cut film and used as a near-infrared cut filter with a heat-welding function.

  As the near-infrared cut film, a film provided with a near-infrared cut layer by applying a solution containing a near-infrared (850 to 1100 nm) absorbing dye and a binder resin on one side of a transparent plastic substrate is suitable. A film formed by a solution casting method from a solution containing an absorbing dye and a binder resin may be used.

  As the near-infrared absorbing dye, conventionally known diazo dyes, diimonium dyes, dithiol metal compounds and the like can be used. One or more dithiol nickel compounds represented by the formula (1) proposed by the present inventor and / or Or one or more combinations of diimonium compounds represented by formula (2), and one or more dithiol nickel compounds represented by formula (3) and / or dithiol nickel compounds represented by formula (4) The combination which added is preferable.

(Wherein R _{1 to} R ₆ are the same as or different from each other, and represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.)

(Wherein X is (CH ₃ SO ₂ ) ₂ N or SbF ₆ , R _{7 to} R ₁₄ are the same as or different from each other, and are a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or 6 carbon atoms). To 24 aryl groups.)

(Wherein R15 to R18 are the same as or different from each other, and are an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 24 carbon atoms, an aralkyl group having 7 to 28 carbon atoms, and 1 carbon atom) To an alkylamino group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a halogen atom or a hydrogen atom.)

  The binder resin is not particularly limited as long as the transparency (visible light transmittance) of the layer is not impaired. Polyester such as olefin-maleimide copolymer, polycarbonate, polyarylate, polyethylene terephthalate, polyethylene naphthalate, norbornene-based Resins such as resin, acrylic resin, and triacetyl cellulose can be used, but polycarbonate, polyarylate, polyester, norbornene resin, and acrylic resin are particularly preferable in terms of productivity, weather resistance, and transparency. It is.

  The near-infrared cut layer is formed by preparing a solution containing a near-infrared absorbing dye and a binder resin, brush coating, spray coating, dip coating, roll coating, calendar coating, spin coating, bar coating, gravure coating, die coating, and screen. The coating can be carried out by coating and drying on a transparent plastic substrate by a coating method such as printing.

Although there is no restriction | limiting in particular as a transparent plastic base | substrate, For example, the film of thickness 25-200 micrometers which consists of plastics, such as polyester, such as a polyethylene terephthalate, acrylic resin, a polycarbonate, a polystyrene, a methyl methacrylate-styrene copolymer, is mentioned. It is done.
The transparent plastic substrate may have various functions such as an ultraviolet absorption function and an antireflection function by itself or by forming a layer on the surface.

The thickness of the near-infrared cut layer thus formed (after drying) is usually selected in the range of 1 to 50 μm, preferably 5 to 25 μm.
When the thickness of the near-infrared cut layer (after drying) is less than 1 μm, the film-forming property at the time of coating is very poor, the yield is lowered, and the weather resistance may be deteriorated. If it exceeds 50 μm, it may be difficult to maintain film thickness accuracy.

  Near-infrared cut film does not have a transparent plastic substrate, from a solution containing a near-infrared absorbing dye and a binder resin, by a method such as the solution casting method similar to the case of manufacturing the above-described heat-adhesion film for color correction, It can also be formed as an independent film having a thickness of 25 to 200 μm.

The blending amount of the near-infrared absorbing dye is a unit area of the near-infrared cut film, that is, 0.05 mg to 800 mg per m ² , preferably 0.08 mg to 600 mg per m ² , more preferably 0.1 mg to 400 mg per m ^2. This range is appropriate.
If the blending amount is less than the above range, the desired absorption capacity may not be obtained, and if it exceeds the above range, the visible light transmittance may decrease.
In addition, in addition to a near-infrared absorption pigment | dye, an ultraviolet absorption pigment | dye and a color correction pigment | dye can also be mix | blended with a near-infrared cut film.

  The near-infrared cut filter with a heat welding function of the present invention can be obtained by laminating a heat correction film for color correction and a near-infrared cut film and heating them at a temperature of 35 to 210 ° C. for about 0.01 to 120 minutes. it can.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
Various characteristics were measured under the following conditions and methods.

(1) Chromaticity: (Y, x, y) and visual field side reflectance Measured using a colorimeter (model number: CM-3600d) manufactured by Minolta, with light source: C and visual field: 10 °.
(2) Haze and total light transmittance (TT)
Using a turbidity meter (model number: NDH2000) manufactured by Nippon Denshoku Industries Co., Ltd., measured by the method defined in JIS K7136
(3) Transmittance and transmittance curve for each wavelength Measured using a spectrometer (model number: V-530) manufactured by JASCO Corporation.
(4) Adhesive strength (tensile strength test)
Measured by the method defined in JIS Z0237: 2000 “Testing method for adhesive tape / adhesive sheet 10.4 Measurement of 180 ° peeling adhesive strength”

[Preparation of near infrared cut film 1]
100 parts by mass of 1,3-dioxolane, 21 parts by mass of polycarbonate resin (manufactured by Teijin Chemicals Ltd., trade name: Panlite L-1250Z-100), a diimonium compound represented by formula (5) (maximum absorption wavelength: 1073 nm, mass Absorption coefficient 73.22 mL / g · cm) 0.42 parts by mass, dithiol nickel compound represented by formula (6) (maximum absorption wavelength 863 nm, mass absorption coefficient 56.79 mL / g · cm) 0.2 parts by mass and A dithiol nickel compound represented by formula (7) (maximum absorption wavelength 792 nm, mass extinction coefficient 52.92 mL / g · cm) was added and dissolved to obtain a resin solution.

  This resin solution was coated on a polyester film (product name: A4300, thickness: 100 μm) using a die coater (manufactured by Thermatronics) with a gap size of 100 μm, and dried at 80 ° C. for 1 minute. An 800 mm × 200 M roll-shaped near infrared cut film A-1 having a 10 μm thick near infrared cut layer was obtained.

The compounding amount per unit area of each pigment in the near infrared cut film A-1 is as follows.
Diimonium compound represented by formula (5): 187 mg / m ²
Dithiol nickel compound represented by formula (6): 52 mg / m ²
Dithiol nickel compound represented by formula (7): 15 mg / m ²

[Preparation of near infrared cut film 2]
The polyester film (Toyobo Co., Ltd., trade name: A4300, thickness 100 μm) was changed to an anti-reflection film with UV-cut function (Nippon Yushi Co., Ltd .: trade name: Ryalk 7710UV), and the back side of the antireflection layer-forming surface of this film In addition to forming a near-infrared cut layer, a roll-like near-infrared cut film A-2 was obtained in the same manner as in [Preparation of near-infrared cut film 1].

The compounding amount per unit area of each pigment in the near-infrared cut film A-2 is as follows.
Diimonium compound represented by formula (5): 187 mg / m ²
Dithiol nickel compound represented by formula (6): 52 mg / m ²
Dithiol nickel compound represented by formula (7): 15 mg / m ²

[Preparation of near-infrared cut film # 3]
Other than changing the diimonium compound represented by the formula (5) to the diimonium compound represented by the same mass of the formula (8) (maximum absorption wavelength 1074 nm, mass extinction coefficient 68.84 mL / g · cm), the above [ Preparation in the same manner as in Preparation of near-infrared cut film 2], a roll-like near-infrared cut film A-3 was obtained.

The blending amount per unit area of each pigment in the near infrared cut film A-3 is as follows.
Diimonium compound represented by formula (8): 187 mg / m ²
Dithiol nickel compound represented by formula (6): 52 mg / m ²
Dithiol nickel compound represented by formula (7): 15 mg / m ²

[Preparation of adhesive film]
To 100 parts by mass of an acrylic pressure-sensitive adhesive (manufactured by Nippon Shokubai Co., Ltd., trade name: Alloset 8157), 1.5 parts by mass of a crosslinking agent (manufactured by Nippon Polyurethane Co., Ltd., trade name: Coronate L-55E) is blended sufficiently. Stir.
When the obtained solution was coated with a die coater (manufactured by Thermatronics) with a gap size of 100 μm, the solid content was adjusted with a toluene / ethyl acetate mixed solvent so that the thickness after drying was 25 μm. After that, it was coated on a peeling polyester film (trade name: MRF75, thickness 75 μm, manufactured by Toyobo Co., Ltd.), dried at 90 ° C. for 1 minute to form a 800 mm × 200 M roll film, and further released The coated surface was covered with a film and then wound on a roll to form an 800 mm × 200 M roll adhesive film B-1.

Example 1
Kayaset Blue N (maximum absorption) manufactured by Nippon Kayaku Co., Ltd., which is a color correction dye, in a hot-melt polyester resin solution (Diabond Kogyo Co., Ltd., trade name: SP3300X1, Picat softening point at drying 125 ° C., solid content concentration: 30% by mass) Wavelength 644 nm, mass extinction coefficient 54000 mL / g · cm) and the cyanine compound represented by formula (9) (maximum absorption wavelength 587 nm, mass extinction coefficient 337.6 mL / g · cm) for each 1 part by mass of the solution. The resin solution added with 0.0002 parts by mass is coated on a peeling polyester film (manufactured by Toyobo Co., Ltd., trade name: MRF75, thickness 75 μm) by a die coating method so that the dry film thickness is 20 μm, and at 80 ° C. It dried for 1 minute and obtained 800 mm x 200M roll-shaped heat welding film C-1.

The blending amount per unit area of the color correction pigment in the heat welding film C-1 is as follows.
Kayaset Blue N: 32mg / m ²
Cyanine compound represented by formula (9): 32 mg / m ²
One hour after drying, this heat-welded film C-1 was bonded to the near-infrared cut layer surface of the near-infrared cut film A-1 with a hot-roll laminator, and a near-infrared cut with a roll-like heat-welding function of 800 mm × 200 M was obtained. Filter D-1 was prepared.

This near-infrared cut filter D-1 with a heat welding function is cut out to 10 × 10 cm, the peeling polyester film is peeled off, the SP3300X1 coated surface is the glass side, and the surface is made into 10 × 10 cm × 0.2 t blue plate glass. Heating was performed for 1 minute with an iron at about 100 ° C., and they were bonded together.
It was 21.5 N / 25mm when the adhesive force of the film and glass was measured, and it had sufficient adhesive force.
When an endurance test of 90 ° C. × 500 hours and 60 ° C./RH 90% × 500 hours was performed on the optical filter obtained by bonding the near-infrared cut filter D-1 with a heat welding function to a blue plate glass, it is shown in Table 1. As described above, it was found that the color value Yxy hardly changed and was very stable. In addition, the spectral spectra before and after the heat test are shown in FIG. 1 (90 ° C. × 500 hours) and FIG. 2 (60 ° C./RH 90% × 500 hours), and the spectrum is also very stable. I understood that. (In the figure, the solid line is the spectral spectrum before the heat test and the dotted line is the spectroscopic spectrum after the heat test, but the solid line is the solid line.)

Example 2
In the case of the heat-sealed film C-1 of Example 1 except that the color correction dye Kayaset Blue N was changed to the same mass Nippon Kayaku Kayaset Red B (maximum absorption wavelength 520 nm, mass extinction coefficient 44000 mL / g · cm) In the same manner as described above, a heat-welded film C-2 was obtained.
The blending amount per unit area of the color correction pigment in the heat welding film C-2 is as follows.
Kaya Set Red B: 32mg / m ²
Cyanine compound represented by formula (9): 32 mg / m ²
Except having used the heat welding film C-2, it carries out similarly to the case of the near infrared cut filter D-1 with a heat welding function of Example 1, and prepares the near infrared cut filter D-2 with a heat welding function. did.

About the optical filter formed by laminating the near-infrared cut filter D-2 with a heat welding function to the blue plate glass in the same manner as in Example 1, the adhesion between the film and the glass was measured in the same manner as in Example 1. It was 5 N / 25 mm and had sufficient adhesion.
Furthermore, the durability test of 90 degreeC x 500 hours and 60 degreeC * RH90% x 500 hours similar to Example 1 was implemented. As a result, it was found that the color value Yxy hardly changed as shown in Table 1 and was very stable. In addition, the spectral spectra before and after the heat test are shown in FIG. 3 (90 ° C. × 500 hours) and FIG. 4 (60 ° C./RH 90% × 500 hours), and the spectrum is also very stable. I understood that. (In the figure, the solid line is the spectral spectrum before the heat test and the dotted line is the spectroscopic spectrum after the heat test, but the solid line is the solid line.)

Example 3
10 × 10 cm polyester film (trade name: 5100, thickness 100 μm, manufactured by Toyobo Co., Ltd.) was used instead of blue plate glass, and near infrared cut film A-2 was used instead of near infrared cut film A-1. Was bonded in the same manner as in Example 1, and the adhesion between the film and the film was measured in the same manner as in Example 1. As a result, it was 23.8 N / 25 mm and had sufficient adhesion.

Example 4
Except for changing the near-infrared cut film A-1 to the near-infrared cut film A-3, the same process as in the case of the near-infrared cut filter D-1 with a thermal welding function of Example 1 was performed, and the near-infrared with a thermal welding function was performed. Cut filter D-3 was obtained.
About the optical filter formed by sticking this near-infrared cut filter D-3 with a heat-welding function to blue glass in the same manner as in Example 1, when the adhesion between the film and the glass was measured in the same manner as in Example 1, 21 It was 2 N / 25 mm and had sufficient adhesion.
In addition, the same durability test as in Example 1 was performed. As a result, it was found that the color value Yxy hardly changed as shown in Table 1 and was very stable. In addition, the spectral spectra before and after the heat test are shown in FIG. 5 (90 ° C. × 500 hours) and FIG. 6 (60 ° C./RH 90% × 500 hours), and the spectrum is also very stable. I understood that. (In the figure, the solid line is the spectral spectrum before the heat test and the dotted line is the spectroscopic spectrum after the heat test, but the solid line is the solid line.)

Example 5
Example 1 except that the hot-melt polyester resin solution was changed to a solution in which a hot-melt ethylene-vinyl acetate copolymer resin (manufactured by Tosoh Corporation, trade name: Mersen G) was dissolved in tetrahydrofuran to a solid content concentration of 30% by mass. It implemented similarly to the case of the heat welding film C-1, and obtained the heat welding film C-3.
The near-infrared cut filter D-1 with a heat-welding function of Example 1 except that the heat-welded film C-3 was used and the near-infrared cut film A-3 was used instead of the near-infrared cut film A-1. In the same manner as in Example 1, a near infrared cut filter D-4 with a heat welding function was prepared.
About the optical filter formed by laminating the near-infrared cut filter D-4 with a heat welding function to the blue sheet glass in the same manner as in Example 1, when the adhesive force between the film and the glass was measured in the same manner as in Example 1, 21 It was 7 N / 25 mm and had sufficient adhesion.
In addition, the same durability test as in Example 1 was performed. As a result, it was found that the color value Yxy hardly changed as shown in Table 1 and was very stable. In addition, the spectral spectra before and after the heat test are shown in FIG. 7 (90 ° C. × 500 hours) and FIG. 8 (60 ° C./RH 90% × 500 hours), and the spectrum is also very stable. I understood that. (In the figure, the solid line is the spectral spectrum before the heat test and the dotted line is the spectroscopic spectrum after the heat test, but the solid line is the solid line.)

Comparative Example 1
10 minutes after bonding the cover film to the adhesive film B-1, the cover film was peeled off and an attempt was made to bond with the near-infrared cut film A-1. It was.

Comparative Example 2
After the adhesive film B-1 was bonded to the cover film, it was cured at room temperature, and after a certain period of time, the cover film was peeled off and examined to be attached to the near infrared cut film A-1, after 5 days. We were able to paste together without any problems for the first time.
With respect to the optical filter in which the near-infrared cut film A-1 was bonded to the blue plate glass through the adhesive film B-1, the adhesion between the film and the glass was measured in the same manner as in Example 1. As a result, it was 20 N / 25 mm. It was.

Comparative Example 3
In the liquid forming the adhesive layer, Nippon Kayaku Kayaset Red B (maximum absorption wavelength 520 nm, mass extinction coefficient 44000 mL / g · cm), which is a color correction pigment, and the cyanine compound represented by the above formula (9) , Acrylic pressure-sensitive adhesive (Nippon Shokubai Co., Ltd., trade name: Alloset 8157) A roll-shaped pressure-sensitive adhesive film was prepared in the same manner as in [Preparation of pressure-sensitive adhesive film] except that 0.0002 parts by weight was added to 1 part by weight. B-2 was prepared.
The blending amount per unit area of the color correction pigment in the adhesive film B-2 is as follows.
Kaya Set Red B: 32mg / m ²
Cyanine compound represented by formula (9): 32 mg / m ²
After drying, the film was cured for 5 days, and the adhesive film B-2 from which the cover film on one side was peeled off was bonded to the back side of the near infrared cut layer surface of the near infrared cut film A-1, and this was cut out and the cover film was peeled off. It bonded together to the blue plate glass of * 10cm * 0.2t.
With respect to the optical filter in which the near-infrared cut film A-1 was bonded to the blue plate glass via the adhesive film B-2, the adhesion between the film and the glass was measured in the same manner as in Example 1. As a result, it was 19 N / 25 mm. It was.
An endurance test was carried out at 90 ° C. × 500 hours and 60 ° C./RH 90% × 500 hours with respect to the optical filter in which the near-infrared cut film A-1 was bonded to the blue sheet glass through the adhesive roll B-2.
As a result, as shown in Table 1, the color value Yxy showed a significant change, and the color was not stable before and after the test. In addition, the spectral spectra before and after the heat test are shown in FIG. 9 (90 ° C. × 500 hours) and FIG. 10 (60 ° C./RH 90% × 500 hours). It was. (In the figure, the solid line is the spectral spectrum before the heat test and the dotted line is the spectroscopic spectrum after the heat test, but the solid line is the solid line.)

  As is apparent from Examples 1 to 5 and Comparative Examples 1 to 3, when a pressure-sensitive adhesive is used, it cannot be stably bonded unless the curing time is applied for about 5 days at room temperature, and it has a completed heat welding function. Near-infrared cut film has extremely poor stability against heat and humidity. On the other hand, the heat welding type can exhibit sufficient adhesive force after drying for several minutes, and is very stable against heat and humidity.

It is a spectrum which shows the result of the heat test (90 degreeC x 500 hours) of the optical filter obtained in Example 1. It is a spectrum which shows the result of the heat test (60 degreeC * RH90% x 500 hours) of the optical filter obtained in Example 1. FIG. It is a spectrum which shows the result of the heat test (90 degreeC x 500 hours) of the optical filter obtained in Example 2. It is a spectrum which shows the result of the heat test (60 degreeC * RH90% x 500 hours) of the optical filter obtained in Example 2. FIG. It is a spectrum which shows the result of the heat test (90 degreeC x 500 hours) of the optical filter obtained in Example 4. It is a spectrum which shows the result of the heat test (60 degreeC * RH90% x 500 hours) of the optical filter obtained in Example 4. FIG. It is a spectrum which shows the result of the heat test (90 degreeC x 500 hours) of the optical filter obtained in Example 5. It is a spectrum which shows the result of the heat test (60 degreeC * RH90% x 500 hours) of the optical filter obtained in Example 5. FIG. It is a spectrum which shows the result of the heat test (90 degreeC x 500 hours) of the optical filter obtained in the comparative example 3. It is a spectrum which shows the result of the heat test (60 degreeC, RH90% x500 hours) of the optical filter obtained by the comparative example 3.

Claims (3)

Solution flow from a thermoplastic transparent resin containing a color correction dye having a Picat softening point of 30 to 150 ° C., a maximum absorption wavelength at 380 to 780 nm, and a mass absorption coefficient of the maximum absorption wavelength of 10 mL / g · cm or more A heat-adhesive film for color correction, which is formed to a thickness of 5 to 200 μm by a drawing method. The heat-adhesive film for color correction according to claim 1, wherein the thermoplastic transparent resin is an acrylic resin, a polyester resin, a polyvinyl butyral resin, or an ethylene-vinyl acetate copolymer resin. The heat correction film for color correction according to claim 1 or 2 and a near-infrared cut film are laminated, an average light transmittance in a wavelength range of 380 to 780 nm is 40% or more, and a wavelength of 850 to 850. A near-infrared cut filter with a thermal welding function, wherein an average light transmittance in a range of 1100 nm is 20% or less.

Images