JP2006350081A - Near-infrared ray shielding film, and near-infrared ray shielding member and display device with same, and coating material for forming near-infrared ray shielding film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a near-infrared ray shielding film in which no fear of change of an outwardly viewed color caused by light from an external light source exists, and with which color reproducibility is improved in accordance with light-emission characteristics of respective display devices by making light transmission distribution of visible rays close to that of natural light and uniform as far as possible, a near-infrared ray shielding member and a display device equipped with the same, and a coating material for forming the near-infrared ray shielding film. <P>SOLUTION: The near-infrared ray shielding film is characterized by a fact that a difference between a chromaticity a<SP>*</SP>of reflected light based on a light source A of an L<SP>*</SP>a<SP>*</SP>b<SP>*</SP>colorimetric system and that based on a light source D65, normalized by CIE, and a difference between a chromaticity b<SP>*</SP>of reflected light based on the light source A of the L<SP>*</SP>a<SP>*</SP>b<SP>*</SP>colorimetric system and that based on the light source D65, are 1 or less in common. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a near-infrared shielding film, a near-infrared shielding member and a display device including the same, and a paint for forming a near-infrared shielding film, and more particularly, a plasma display (PDP), a liquid crystal display (LCD), an electroluminescence display ( ELD), cathode ray tube (CRT), projection (PJTV) and other image display devices, which are suitable for display surfaces, and by making the light transmittance distribution of visible light uniform as close to natural light as possible. The near-infrared shielding film capable of improving the color reproducibility in accordance with the light emission characteristics of each display device, and the near-infrared shielding member and the display device having no change in appearance color due to light from the light source The present invention also relates to a paint for forming a near-infrared shielding film.

Conventionally, in various image display devices such as a plasma display panel (PDP), a liquid crystal display (LCD), an electroluminescence display (ELD), a cathode ray tube (CRT), a fluorescent display tube, and a field emission display, in principle, red (R ), Blue (B), and green (G) are combined to display a color image.
By the way, in these image display apparatuses, it is difficult to obtain ideal three primary colors because the light intensity of each of the three primary colors red (R), blue (B), and green (G) is different. Therefore, in order to perform color display with an ideal hue, it has been proposed to perform color correction for correcting the color balance of the display color using an optical filter that absorbs light of a specific wavelength.

In particular, in the PDP, since the intensity of light having a specific wavelength caused by a rare gas such as neon sealed in a cell is strong, the color purity of the display may be hindered. Therefore, an optical filter that absorbs light of a specific wavelength to improve the color purity of the display and selectively cuts light of a specific wavelength such as near infrared rays is used (see Patent Documents 1 and 2). ).
By attaching such an optical filter to the display surface of the PDP, the color purity of the PDP image can be greatly improved. The optical filter also plays a major role in the design of the PDP, and is also a point at the time of purchase because it affects the image of the interior such as luxury.
JP 2001-228323 A JP 2002-187229 A

By the way, the conventional optical filter has a problem that the color tone or appearance color of the display surface of the PDP varies greatly depending on the light source of external light.
For example, the display surface of a PDP under a fluorescent lamp viewed at an electronic store before purchase is greatly different from the display surface of a PDP under a white light bulb viewed in a living space such as a living room after purchase. In addition, there is a risk that a complaint from a customer, such as whether the delivered PDP is a product different from the PDP seen at the store, may occur.
This is because the phenomenon that the color tone or appearance color of the display surface of the PDP varies greatly depending on the light source of external light is caused by the fact that the optical filter has a characteristic of metamerism.

This metamerism is an index that indicates the degree of color change or external color change due to the color of external light, and uses the L ^* a ^* b ^* color system standardized by the CIE (International Lighting Commission) as follows. Is defined.
(1) L ^* a ^* b ^* Difference Δa ^* between the chromaticity a ^* of the reflected light from the A light source of the color system and the chromaticity a ^* of the reflected light from the D65 light source
Δa ^* = a ^* value (A light source) −a ^* value (D65 light source)
(2) L ^* a ^* b ^* Difference Δb ^* between the chromaticity b ^* of the reflected light from the A light source of the color system and the chromaticity b ^* of the reflected light from the D65 light source
Δb ^* = b ^* value (A light source) −b ^* value (D65 light source)

The lower the metamerism, the smaller the degree of color change or color change due to external light color. Therefore, the lower the metamerism, the better the quality.
For example, when the metamerism of the optical filter is high, the color tone varies greatly depending on the external light source, the color tone on the display surface of the PDP changes, and the quality of the image display device is degraded. In addition, since the color tone of the display surface of the PDP is greatly different depending on the light source, the image as the interior is lowered, and the quality in the design is also lowered.

  The present invention has been made to solve the above-described problems, and there is no possibility that the appearance color may be changed by light from an external light source, and the light transmittance distribution of visible light is as uniform as possible to natural light. By providing a near-infrared shielding film that can improve color reproducibility according to the light emission characteristics of each display device, a near-infrared shielding member and a display device including the same, and a paint for forming a near-infrared shielding film The purpose is to provide.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the L ^* a ^* b ^* color system standardized by CIE in a near-infrared shielding film containing a dye. the difference between the chromaticity ^{a *} of the reflected light by the chromaticity ^{a *} and D65 light source of the reflected light by the light source a, and the ^L * ^a * ^{b *} chromaticity of the reflected light by the color system a source of ^{b *} and illuminant D65 If the difference from the chromaticity b ^* of the reflected light by both is 1 or less, there is no possibility that the appearance color will be changed by the light from the external light source, and the specific color generated on the display surface of the display device such as PDP It has been found that light of a wavelength can be selectively shielded, and therefore color reproducibility can be improved in accordance with the light emission characteristics of each display device, and the present invention has been completed.

That is, the near-infrared shielding film of the present invention is a near-infrared shielding film containing a dye, and the color of light reflected by an A light source of the L ^* a ^* b ^* color system standardized by CIE. The difference between the degree a ^* and the chromaticity a ^* of the reflected light from the D65 light source, and the chromaticity b ^* of the reflected light from the A ^* light source of the L ^* a ^* b ^* color system and the chromaticity b of the reflected light from the D65 light source The difference from ^* is 1 or less.

  The full width at half maximum of the maximum absorption spectrum in the visible light region of the film is 24 nm or less, and the difference between the maximum value Ax and the minimum value An in the wavelength band A of 450 nm to 520 nm is 3.0% or less. The difference between the maximum value Ax and the maximum value Bx of the light transmittance in the wavelength band B of 620 nm or more and 670 nm or less of the film is preferably 5.0% or less.

The maximum absorption spectrum is preferably an absorption spectrum in a wavelength band of 585 nm ± 35 nm.
The dye contains a near-infrared absorbing dye that absorbs light in the near-infrared region, a selective absorbing dye that selectively absorbs light in a predetermined wavelength band of visible light wavelength bands, and a color adjusting dye. It is preferable.

The near-infrared shielding member of the present invention comprises the near-infrared shielding film of the present invention on a transparent substrate.
The transparent substrate is preferably a transparent polymer film or a transparent polymer sheet.

  The display device of the present invention is characterized by comprising the near-infrared shielding member of the present invention on the display surface.

  The near-infrared shielding film-forming paint of the present invention includes a near-infrared absorbing dye that absorbs light in the near-infrared region, a selective absorbing dye that selectively absorbs light in a predetermined wavelength band among visible light wavelength bands, and color adjustment. And a full width at half maximum of the maximum absorption spectrum of the selective absorption dye is 24 nm or less.

According to the near-infrared shielding film of the present invention, CIE by the reflected light from the chromaticity a ^* and D65 light source of the reflected light by the A source of standardized L ^* a ^* b ^* color system chromaticity a ^* and the the difference, and the difference between the chromaticity b ^* of the reflected light by the chromaticity b ^* and D65 light source of the reflected light by the a light source of the L ^* a ^* b ^* color system, since the both 1 or less, out of the light source There is no possibility that the appearance color is changed by the light from the light, and the metamerism of the film can be improved.
In addition, light of a specific wavelength in the visible light region can be selectively shielded, and various transmitted colors can be adjusted by combining each pigment. Therefore, the color reproducibility of the display image when a plurality of display devices are combined can be improved.

According to the near-infrared shielding member of the present invention, since the near-infrared shielding film of the present invention is provided on the transparent substrate, light of a specific wavelength in the visible light region can be selectively shielded, and each dye Various transmission color adjustments can be made by the combination. Therefore, the color reproducibility of the display image when a plurality of display devices are combined can be improved.
In addition, since there is no possibility that the appearance color is changed by light from an external light source, the metamerism of the film can be improved.

According to the display device of the present invention, since the near-infrared shielding member of the present invention is provided on the display surface, light of a specific wavelength emitted from the display device can be selectively shielded in the visible light region. The light transmittance distribution can be made as uniform as possible with natural light. Therefore, color reproducibility on the display surface can be improved.
Further, since there is no possibility that the appearance color is changed by light from an external light source, metamerism on the display surface can be improved.

  According to the paint for forming a near-infrared shielding film of the present invention, a near-infrared absorbing dye that absorbs light in the near-infrared region, a selective-absorbing dye that selectively absorbs light in a predetermined wavelength band out of the visible light wavelength band, Since it contains a color adjusting dye and the half-value width of the maximum absorption spectrum of the selective absorption dye is 24 nm or less, light in the near-infrared region and light with a specific wavelength can be selectively shielded. Therefore, the color reproducibility of the film can be improved, and furthermore, there is no risk of the appearance color changing due to light from an external light source, so a near-infrared shielding film with improved metamerism can be easily and inexpensively Can be manufactured.

The best mode for carrying out the near-infrared shielding film of the present invention, the near-infrared shielding member and display device including the same, and the near-infrared shielding film-forming coating material will be described.
This embodiment is specifically described for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified.

FIG. 1 is a schematic cross-sectional view showing a near-infrared shielding film (near-infrared shielding member) according to an embodiment of the present invention.
The near-infrared shielding film 1 includes a transparent film (transparent substrate) 2 and a near-infrared shielding film 3 formed on the surface (one main surface) 2a of the transparent film 2.

The material of the transparent film 2 is not particularly limited as long as it has sufficient strength and can be a polymer film transparent to visible light. For example, cellulose acetate, triallyl cyanurate ( TAC), polystyrene (PS), polyethylene terephthalate (PET), polyether, polyimide, epoxy, phenoxy, polycarbonate (PC), polyvinylidene fluoride, acrylic, polyethylene (PE), nylon, polyvinyl alcohol (PVA), polytetrafur It can be suitably selected from olethylene (PTFE) and polyfluoroacetylene (PFA).
Further, the thickness of the transparent resin film 2 is not particularly limited, and a thickness of about 50 to 250 μm can be used.

Depending on the application, a transparent sheet may be used instead of the transparent film 2. In this case, the material of the transparent sheet may be any material as long as it has sufficient strength and can be a transparent polymer sheet, and a sheet made of the above-described material is preferable.
The thickness of the transparent sheet is not particularly limited, and usually a thickness of about 50 μm to 10 mm can be used.

The near-infrared shielding film 3 is a near-infrared shielding film containing a dye in an organic polymer, and the organic polymer has good wettability with the contained dye and is sufficient for visible light. Any material can be used as long as it can ensure transparency, for example, acrylic resin, polyester resin, polyurethane resin, polyolefin resin, polystyrene resin, cellulose, polyvinyl pyrrolidone, polyvinyl alcohol, polyethylene glycol, polypropylene glycol, butyral resin, alkyd resin. Celluloses such as vinyl chloride resin and ethyl cellulose can be used alone or in combination.
These organic polymers may be appropriately selected from any one of a room temperature curable resin, an ultraviolet curable resin, and an electron beam curable resin depending on applications.

The dye contains a near-infrared absorbing dye that absorbs light in the near-infrared region, a selective absorbing dye that selectively absorbs light in a predetermined wavelength band out of the visible light wavelength band, and a color-adjusting dye. It is necessary.
Near-infrared absorbing dyes are dyes that selectively absorb light in the near infrared radiation (NIR) wavelength band (2.5 μm to 0.76 μm), such as polymethine, phthalocyanine, naphthalocyanine, metal Examples of the dye include complex, aminium, imonium, diimonium, anthraquinone, dithiol metal complex, naphthoquinone, indolephenol, azo, and triallylmethane.
Among these dyes, metal complex-based, aminium-based, phthalocyanine-based, naphthalocyanine-based, and diimonium-based pigments are particularly preferable because they have excellent near-infrared absorption performance.

As the selective absorption dye, it is necessary that the half width of the maximum absorption spectrum in the wavelength band of visible light is 24 nm or less. As such a dye, for example, squarylium-based, azo-based, condensed azo-based, phthalocyanine-based , Anthraquinone, indigo, perinone, perylene, dioxazine, quinacridone, methine, isoindolinone, quinophthalone, pyrrole, thioindigo, porphyrin, metal complex, and other organic pigments or organic dyes Inorganic pigments such as carbon black, iron oxide, chromium oxide, and titanium oxide, or noble metal colloids such as gold colloid, platinum colloid, and silver colloid.
These selective absorption dyes may be selected from one kind or two or more kinds according to light of a wavelength band selectively absorbed from the above dye group.

  As the color adjusting dye, the half-value width of the maximum absorption spectrum in the visible light region of the near-infrared shielding film 3 is 24 nm or less, and the maximum value Ax of the light transmittance in the wavelength band A of the near-infrared shielding film 3 is 450 nm or more and 520 nm or less. The difference between the maximum value Ax and the minimum value An is 3.0% or less, and the difference between the maximum value Ax and the maximum value Bx of the light transmittance in the wavelength band B of 620 nm or more and 670 nm or less of the near infrared shielding film 3 is 5. Any organic dye or organic pigment selected from a group of yellow, blue, purple and red pigments may be used as long as it can exhibit a light transmission spectrum of 0% or less. Are used in combination. If necessary, “black” may be added to this pigment group.

The organic dye is not particularly limited as long as it is soluble in the organic polymer described above. Examples of the dye include ketones and esters, oil-soluble dyes soluble in aromatic solvents, and dyes soluble in organic solvents. Either can be used.
The organic pigment is not particularly limited as long as it is soluble in the above-described organic polymer, and examples thereof include azo, phthalocyanine, quinacridone, and dioxazine.

This near-infrared shielding film 3 has a difference Δa ^* between the chromaticity a ^* of the reflected light from the A ^* light source of the L ^* a ^* b ^* colorimetric system standardized by CIE and the chromaticity a ^* of the reflected light from the D65 light source ^. (= A ^* value (A light source) −a ^* value (D65 light source)), and the chromaticity b ^* of the reflected light from the A light source of the L ^* a ^* b ^* color system and the color of the reflected light from the D65 light source The difference Δb ^{* from the} degree b ^* (= b ^* value (A light source) −b ^* value (D65 light source)) is preferably 1 or less, more preferably 0.5 or less, and still more preferably 0.3 or less. is there.
These differences Δa ^* and Δb ^* indicate that the smaller the numerical value, the smaller the color change of the appearance color due to the external light color. Therefore, the smaller the numerical value, the lower the metamerism, and the smaller the change in the color tone of the film surface due to the light source of external light.

Here, the A light source is a light source that emits light having an emission spectrum called “bulb color”, and an incandescent light bulb using tungsten as a filament is preferably used.
The D65 light source is a light source that emits light having an emission spectrum such that the saturation is “0” (achromatic color), and is a so-called white light source.

As shown in FIG. 2, the near-infrared shielding film 3 has a full width at half maximum W of the maximum absorption spectrum S in the visible light region of 24 nm or less, more preferably 22 nm or less. This maximum absorption spectrum S is preferably an absorption spectrum in a wavelength band N of 585 nm ± 35 nm.
In the near-infrared shielding film 3, the difference between the maximum value Ax and the minimum value An of the light transmittance in the wavelength band A of 450 nm or more and 520 nm or less is preferably 3.0% or less, more preferably 1.5 or less, More preferably, it is 1.0 or less.
The difference between the maximum value Ax and the maximum value Bx of the light transmittance in the wavelength band B of 620 nm or more and 670 nm or less is preferably 5.0% or less, more preferably 4.0 or less, and still more preferably 3. 5 or less.

Next, the manufacturing method of the near-infrared shielding film of this embodiment is demonstrated.
"Near-infrared shielding film forming paint"
A predetermined amount of organic polymer is dissolved and mixed in an organic solvent to prepare a resin composition.
The organic polymer used here may be either solid or liquid as long as it dissolves in the organic solvent described below, and any of room temperature curing type, ultraviolet curing type, and electron beam curing type Although it may be a type, it needs to be able to ensure sufficient transparency with respect to visible light.

  Examples of such organic polymer include acrylic resin, polyester resin, polyurethane resin, polyolefin resin, polystyrene resin, cellulose, polyvinyl pyrrolidone, polyvinyl alcohol, polyethylene glycol, polypropylene glycol, butyral resin, alkyd resin, vinyl chloride resin, Celluloses such as ethyl cellulose are preferably used.

Examples of the organic solvent include, but are not limited to, alcohols such as methanol, ethanol, 2-propanol, n-butanol, and 2-butanol, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, benzene, Aromatic hydrocarbons such as toluene and xylene, saturated monocyclic hydrocarbons such as cyclohexane, β-oxyethyl methyl ether (methyl cellosolve), β-oxyethyl ether (ethyl cellosolve), butyl-β-oxyethyl ether (butyl cellosolve) , Glycol monoethers such as propylene glycol monomethyl ether, ethyl acetate, butyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl Chromatography ether acetate, propylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol esters such as monobutyl ether acetate and the like are suitably used.
These organic solvents may be used alone or in combination of two or more.

Next, the near-infrared absorbing dye that absorbs light in the near-infrared region described above, a selective absorbing dye that selectively absorbs light in a predetermined wavelength band out of the visible light wavelength band, and a color adjusting dye are added to the resin composition. Then, a predetermined amount of each is added to adjust the near-infrared shielding film-forming coating material.
The selection and addition amount of each dye in the near infrared absorbing dye, the selective absorbing dye, and the color adjusting dye are determined by optical characteristics required for the obtained near infrared shielding film. Here, the selection and addition amount of each dye are determined so as to satisfy the required optical characteristics.

Next, a near infrared shielding film is formed on the surface of the transparent film.
The surface of the transparent film is previously cleaned using a cleaning roller or the like, and the surface of the transparent film is spin coated, spray coated, dip coated, bar coated, ink jet, gravure coated, roll coated The coating material for forming a near infrared shielding film is applied by a coating method such as a screen printing method, a knife coater method, a reverse roll coater method, or a kiss coater method.

Next, the near-infrared shielding film forming coating is subjected to, for example, natural standing indoors, drying by a dryer or air blow, heat treatment by a heating furnace, drying treatment or heat treatment by ultraviolet irradiation, etc. Form.
As described above, the near-infrared shielding film can be easily and inexpensively formed on the surface of the transparent film, and thus the near-infrared shielding film 1 can be easily and inexpensively manufactured.

Moreover, if this near-infrared shielding film 1 is fixed by sticking it on the display surface of the display device, for example, the display surface of the PDP, using an adhesive or the like, a specific neon or the like generated from the PDP is specified. It is possible to selectively block light of a wavelength.
In this case, it is possible to adjust the transmitted color while making the light transmittance distribution in the visible light region as uniform as possible with natural light, so that the color reproducibility is improved in accordance with the light emission characteristics of the PDP. It is also possible. In addition, since there is no possibility that the appearance color changes due to light from an external light source, metamerism on the display surface is also reduced.

According to the near-infrared shielding film 3 of the present embodiment, the difference Δa ^* between the chromaticity a ^* of the reflected light from the A ^* light source of the L ^* a ^* b ^* color system and the chromaticity a ^* of the reflected light from the D65 light source, Since the difference Δb ^* between the chromaticity b ^* of the reflected light from the A light source of the L ^* a ^* b ^* color system and the chromaticity b ^* of the reflected light from the D65 light source is set to 1 or less, There is no possibility of changing the appearance color due to light from the light source, and the metamerism of the film can be improved.
In addition, since light having a specific wavelength in the visible light region can be selectively shielded, the light transmittance distribution in the visible light region can be made as uniform as possible with natural light as much as possible. The color reproducibility on the surface of can be improved.

According to the near-infrared shielding film 1 of the present embodiment, since it is constituted by the transparent film 2 and the near-infrared shielding film 3 formed on the surface 2a of the transparent film 2, the appearance color is caused by light from an external light source. There is no possibility of changing, and the metamerism of the near-infrared shielding film 1 can be improved.
In addition, since light having a specific wavelength in the visible light region can be selectively shielded, the light transmittance distribution in the visible light region can be made as uniform as possible with natural light. The color reproducibility of the near infrared shielding film 1 can be improved.

According to the display device of the present embodiment, since the near-infrared shielding film 1 is provided on the display surface such as PDP, it is possible to selectively shield light having a specific wavelength emitted from the display surface such as PDP. The light transmittance distribution in the visible light region can be made as uniform as possible with natural light. Therefore, color reproducibility on the display surface can be improved.
Further, since there is no possibility that the appearance color is changed by light from an external light source, metamerism on the display surface can be improved.

EXAMPLES Hereinafter, although this invention is demonstrated concretely by Examples 1-4 and Comparative Examples 1-4, this invention is not limited by these Examples.
"Example 1"
Resin by dissolving and mixing 100 parts by weight of acrylic resin (Dianar BR-80, glass transition point: 105 ° C., manufactured by Mitsubishi Rayon Co., Ltd.) in a mixed solution of methyl ethyl ketone and toluene (weight ratio, 50:50). A composition was prepared.

A selective absorption dye solution was prepared by dissolving and mixing a selective absorption dye having a half width of 22 nm and a maximum absorption spectrum (λ _max ) of 586 nm in toluene. In addition, a color adjusting dye solution is prepared by dissolving and mixing a color adjusting dye in which the ratio (weight ratio) of red, yellow, and black is 0.5: 0.3: 0.0 in toluene. did.

  Next, hexafluoroantimonic acid of N, N, N, N, -tetrakis (p-diethylaminophenyl) -p-benzoquinone-bis (imonium) as a diimonium compound which is a near-infrared absorbing dye is added to the above resin composition. 2 parts by weight of salt (IRG-022, manufactured by Nippon Kayaku Co., Ltd.) and 1 part by weight of phthalocyanine dye (EEX Color 810K, manufactured by Nippon Shokubai Co., Ltd.) as the second near infrared absorbing dye Further, 2.0 parts by weight of the selective absorption dye solution and 0.5 parts by weight of the color adjusting dye solution were added to prepare a near-infrared shielding film-forming coating material.

  Next, this near-infrared shielding film-forming coating material is dried on a polyethylene terephthalate (PET) film (Cosmo Shine A-4300, thickness: 100 μm, manufactured by Toyobo Co., Ltd.) by a bar coating method. The coating was applied to a thickness of 15 μm, and then allowed to stand naturally in the room and dried to produce the near-infrared shielding film of Example 1.

"Example 2"
The maximum absorption spectrum (λ _max ) of the selective absorption dye is 590 nm, the input amount of the selective absorption dye solution using this selective absorption dye is 1.2 parts by weight, the red, yellow and black dyes for color adjustment. Example 1 except that the ratio (weight ratio) was 0.2: 0.3: 0.6 and the amount of the color adjusting dye solution using this color adjusting dye was 0.8 part by weight. Similarly, the near-infrared shielding film of Example 2 was produced.

"Example 3"
The full width at half maximum of the selective absorption dye is 24 nm, its maximum absorption spectrum (λ _max ) is 590 nm, and the ratio (weight ratio) of each of the red, yellow and black dyes for color adjustment is 0.2: 0.3: 0. 1. A near-infrared shielding film of Example 3 was produced in the same manner as in Example 1 except that the amount of the color adjusting dye solution using this color adjusting dye was 0.6 parts by weight.

Example 4
The maximum absorption spectrum (λ _max ) of the selective absorption dye is 590 nm, the input amount of the selective absorption dye solution using this selective absorption dye is 2.3 parts by weight, the red, yellow and black dyes for color adjustment. A near-infrared shielding film of Example 4 was produced in the same manner as Example 1 except that the ratio (weight ratio) was 0.0: 0.2: 0.0.

“Comparative Example 1”
The half-width of the selective absorption dye is 30 nm, the input amount of the selective absorption dye solution using this selective absorption dye is 3.0 parts by weight, and the ratio (weight ratio) of each of the red, yellow and black dyes for color adjustment 0.1: 0.3: 0.0, a comparison was made in the same manner as in Example 1 except that the input amount of the color adjusting dye solution using this color adjusting dye was 0.3 parts by weight. The near-infrared shielding film of Example 1 was produced.

“Comparative Example 2”
The full width at half maximum of the selective absorption dye is 28 nm, its maximum absorption spectrum (λ _max ) is 590 nm, the input amount of the selective absorption dye solution using this selective absorption dye is 1.8 parts by weight, and the red and yellow color adjustment dyes The ratio of each black pigment (weight ratio) was 0.1: 0.1: 0.2, and the amount of the color-adjusting dye solution using this color-adjusting dye was 0.4 parts by weight. Produced the near-infrared shielding film of Comparative Example 2 in the same manner as in Example 1.

“Comparative Example 3”
The full width at half maximum of the selective absorption dye is 24 nm, the maximum absorption spectrum (λ _max ) is 590 nm, and the ratio (weight ratio) of each of the red, yellow, and black dyes for color adjustment is 0.1: 0.2: 0. 1. A near-infrared shielding film of Comparative Example 3 was prepared in the same manner as in Example 1 except that the amount of the color adjusting dye solution using this color adjusting dye was 0.3 parts by weight.

“Comparative Example 4”
The full width at half maximum of the selective absorption dye is 24 nm, the maximum absorption spectrum (λ _max ) is 590 nm, the input amount of the selective absorption dye solution using this selective absorption dye is 1.3 parts by weight, and the red and yellow color adjustment dyes The ratio (weight ratio) of the black pigments was 0.3: 0.0: 0.1, and the amount of the color-adjusting pigment solution using this color-adjusting pigment was 0.3 parts by weight. Produced the near-infrared shielding film of Comparative Example 4 in the same manner as in Example 1.

In Table 1, the full width at half maximum, the maximum absorption spectrum (λ _max ), the input amount of each of the selective absorption dyes of Examples 1 to 4 and Comparative Examples 1 to 4, the ratios of the red, yellow, and black dyes for color adjustment. The input amount is shown.

"Evaluation of near-infrared shielding film"
The near-infrared shielding films of Examples 1 to 4 and Comparative Examples 1 to 4 were evaluated.
The evaluation items were six items of total light transmittance, half-value width (= half-value width of selective absorbing dye), transmission color, near infrared transmittance, metamerism, and spectral transmittance.
The evaluation method is as follows.

(1) Total light transmittance The total light transmittance of the near-infrared shielding film was measured using a haze meter (manufactured by Tokyo Denshoku Co., Ltd.) in accordance with Japanese Industrial Standard JIS K 7105 “Testing Method for Optical Properties of Plastics”. .
(2) Transmission color Using the color analyzer TOPSCAN TC-1800-MK (manufactured by Tokyo Denshoku Industries Co., Ltd.), the a ^* value and b ^* value of the L ^* a ^* b ^* color system of each sample A D65 light source was used as the standard light, and the measurement was performed twice in the visual field.

(3) Near-infrared transmittance The transmittance of each sample in the near-infrared of 850 nm and 950 nm was measured using a spectrophotometer U-4100 (manufactured by Hitachi High-Technologies Corporation).
(4) Metamerism Spectral color difference meter SE-2000 (manufactured by Nippon Denshoku Industries Co., Ltd.) is used, and as a light source, a D65 light source and an A light source (viewing angle 2 °) are used, and L ^* a ^* b ^* color system A The difference Δa ^* between the chromaticity a ^* of the reflected light from the light source and the chromaticity a ^* of the reflected light from the D65 light source, and the chromaticity b ^{* of the} reflected light from the A light source of this L ^* a ^* b ^* color system The difference Δb ^* from the chromaticity b ^* of the reflected light from the D65 light source was determined.
Δa ^* = a ^* value (A light source) −a ^* value (D65 light source)
Δb ^* = b ^* value (A light source) −b ^* value (D65 light source)

(5) Spectral transmittance Using a spectrophotometer U-4100 (manufactured by Hitachi High-Technologies Corporation), a spectral transmittance of 5 ° was measured.
The evaluation results of the near-infrared shielding films of Examples 1 to 4 and Comparative Examples 1 to 4 are shown in Tables 2 and 3.
FIG. 3 shows the spectral transmittance curves of Examples 1 and 2 and Comparative Example 1.

  According to the above evaluation result, it turned out that the near-infrared shielding film of Examples 1-4 has sufficient near-infrared shielding performance compared with the near-infrared shielding film of Comparative Examples 1-4. It was also found that the optical characteristics in the visible light region can be adjusted according to the light emission characteristics of the display device. Further, it was found that even when the light emission characteristics of external light changed, the color change of the appearance color (reflective color) was extremely small, and the metamerism was excellent.

Therefore, the near-infrared shielding films of Examples 1 to 4 have a smaller color change of the appearance color (reflected color) due to the light source than the near-infrared shielding films of Comparative Examples 1 to 4, and thus light from an external light source Thus, it was found that the appearance color (reflective color) does not change, and the metamerism of the near-infrared shielding film is improved.
Moreover, since the spectral transmittance is excellent, it is possible to improve the color purity of the near-infrared shielding film by making the light transmittance distribution in the visible light region uniform as close to natural light as possible. I understood.

The near-infrared shielding film of the present invention has a difference between the chromaticity a ^* of reflected light by the A light source of L ^* a ^* b ^* color system standardized by CIE and the chromaticity a ^* of reflected light by the D65 light source, And the difference between the chromaticity b ^* of the reflected light from the A light source of the L ^* a ^* b ^* color system and the chromaticity b ^* of the reflected light from the D65 light source is set to 1 or less. It can be applied to any object in which changes in appearance color (reflected color) due to light from the light source and light transmittance distribution in the visible light region are a problem, especially plasma display (PDP), liquid crystal display (LCD), electro When improving the appearance color (reflection color) on the display surface of various image display devices such as luminescence display (ELD), cathode ray tube (CRT), projection (PJTV), and improving the light transmittance distribution in the visible light region It is always effective, its industrial utilization value is very large.

It is a schematic sectional drawing which shows the near-infrared shielding film of one Embodiment of this invention. It is explanatory drawing which shows the absorption spectrum in the visible region of the near-infrared shielding film of one Embodiment of this invention. It is a figure which shows the spectral transmittance curve of Example 1, 2 and Comparative Example 1 of this invention.

Explanation of symbols

1 near-infrared shielding film 2 transparent film 2a surface (one main surface)
3 Near-infrared shielding film

Claims (8)

A near-infrared shielding film containing a dye,
The difference between the chromaticity a ^* of the reflected light from the A light source of the L ^* a ^* b ^* color system normalized by the CIE and the chromaticity a ^* of the reflected light from the D65 light source, and the L ^* a ^* b ^* table near infrared ray shielding film, wherein a difference between the chromaticity b ^* of the reflected light by the chromaticity b ^* and D65 light source of the reflected light by the color system a light source is, are both 1 or less.   The full width at half maximum of the maximum absorption spectrum in the visible light region of the film is 24 nm or less, and the difference between the maximum value Ax and the minimum value An in the wavelength band A of 450 nm to 520 nm is 3.0% or less. The difference between the maximum value Ax and the maximum value Bx of the light transmittance in the wavelength band B of 620 nm or more and 670 nm or less of the film is 5.0% or less. Infrared shielding film.   The near-infrared shielding film according to claim 1, wherein the maximum absorption spectrum is an absorption spectrum in a wavelength band of 585 nm ± 35 nm.   The dye contains a near-infrared absorbing dye that absorbs light in the near-infrared region, a selective absorbing dye that selectively absorbs light in a predetermined wavelength band of visible light wavelength bands, and a color adjusting dye. The near-infrared shielding film according to claim 1, 2 or 3.   A near infrared shielding member comprising the near infrared shielding film according to claim 1 on a transparent substrate.   The near-infrared shielding member according to claim 5, wherein the transparent substrate is a transparent polymer film or a transparent polymer sheet.   A display device comprising the near-infrared shielding member according to claim 5 or 6 on a display surface. A near-infrared absorbing dye that absorbs light in the near-infrared region, a selective absorbing dye that selectively absorbs light in a predetermined wavelength band of visible light wavelength bands, and a color adjusting dye,
A near-infrared shielding film-forming coating material, wherein the half-width of the maximum absorption spectrum of the selective absorption dye is 24 nm or less.

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