JP2000258625A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high contrast and high precision surface treating film excellent in strength by incorporating an organic dye into a surface treating film and providing an absorption peak in a specified wavelength range. SOLUTION: A film can be made achromatic with a burgundy dye and a green dye by using an organic dye obtained by combining a quinacridone dye and a naphthalocyanine dye because the burgundy quinacridone dye having its absorption peak in the range of 550-600 nm and the naphthalocyanine dye having its absorption peak in the range of 650-700 nm have complementary colors. Since a film containing the two-component dye has no absorption peak in the luminescence regions of red and blue phosphors, color purity and contrast are enhanced. The strength of the film is enhanced because the amount of the dye contained in the film is small.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high contrast display device having a surface treatment film formed on a display panel surface.

[0002]

2. Description of the Related Art A typical display device is a cathode ray tube (CRT). With an increase in the image quality of televisions, cathode ray tubes in which a wavelength selective absorption film (optical filter) is formed on the front surface of a face plate have been used.

[0003] The filter selectively absorbs external light of a specific wavelength to prevent reflection of the external light, and also absorbs a side band of a phosphor emission spectrum which causes deterioration of color purity. The purpose is to increase color purity and improve contrast. Usually, this filter is an organic dye / glass gel composite film produced by using a sol-gel method (JP-A-1-320742, JP-A-4-14738).

The organic dye used in the optical filter is a rhodamine-based organic dye from the viewpoint of solubility in a solution. Many rhodamine-based organic dyes have an absorption around 560 to 590 nm, which is the highest in human luminous sensitivity, and efficiently absorb side bands of green and red light emitters to improve color purity and increase contrast. It is effective for

[0005]

The above rhodamine dyes are very effective in improving contrast, but have the following drawbacks. That is, in the above-described wavelength selective absorption film, since the dye having an absorption at 560 to 590 nm strongly develops a reddish purple color, the panel surface of the display device is colored with a strong unique color, and the commercial value is reduced. I will. For this reason, it is necessary to dope a complementary color dye to cancel this color. Normally, there are few dyes having an ideal complementary color relationship, and it is necessary to dope various dyes in order to produce the complementary color.

In this state, the absorption of a plurality of dyes overlaps in the visible light region. B. There is a disadvantage that the light of the emission wavelength of the G light emitter is also absorbed, and the color purity and contrast are reduced.

Further, doping with several kinds of dyes has a drawback that the dye concentration in the film increases and the film strength decreases. Furthermore, since the rhodamine-based dye is a dye, it has a drawback that light resistance is poor.

Further, there has been no surface treatment film having both good wavelength selective absorption performance and good anti-reflection performance.

A rhodamine-based or quinacridone-based organic dye emits a reddish-violet color. To cancel this color, it is necessary to dope a complementary green-based dye. However, ordinary green dyes are insufficient to achromatically color the red-violet dyes described above. This is because the absorption spectrum of the green dye is different from the spectrum of the rhodamine-based or quinacridone-based red-violet absorption spectrum that is complementary to the absorption spectrum of the red-violet color.

For this reason, a method is generally employed in which yellow and blue dyes are mixed to render the rhodamine-based or quinacridone-based red-violet color achromatic. In this case, the blue dye and the yellow dye have absorption in the light-emitting regions of the R luminous body and the B luminous body, and this absorbs the luminescence to lower the color purity contrast. Further, in this case, since the contained pigment increases, the strength of the film becomes insufficient.

In view of the above, it is an object of the present invention to provide a high-contrast, high-definition display device having a surface treatment film having excellent strength.

Another object of the present invention is to provide a display device in which a surface treatment film having both a reflection preventing effect and a wavelength selective absorption effect is formed.

[0013]

Means for Solving the Problems In order to achieve the above object, the present inventors examined the absorption spectra of various red-violet pigments and green pigments, and found that a combination of a quinacridone pigment and a naphthalocyanine pigment was used. Found that the color of the film was sufficiently rendered achromatic.

The gist of the present invention is as follows.

[1] In a display device in which a surface treatment film is formed on a display surface, the surface treatment film contains an organic dye, and is 550-600 nm, 650-700 nm, and 4 nm.
A display device having an absorption peak at 00 to 450 nm.

[2] In the display device, the organic dye is a quinacridone dye or a naphthalocyanine dye.

[3] The display device, wherein the surface treatment film contains conductive fine particles.

[4] The conductive fine particles are ATO, I
The display device includes at least one of TO, Ag, Pd, Pt, and Au.

[5] The display device according to the above aspect, wherein the surface treatment film has a low refractive index film as an upper layer.

[6] The display device according to the above, wherein the surface treatment film has a high refractive index film and a low refractive index film sequentially laminated thereon.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The use of a quinacridone-based dye and a naphthalocyanine-based dye in combination makes it possible to render the film achromatic with two components, a red-violet dye and a green dye.

This is because the quinacridone organic dye has a red-violet transmission performance having an absorption peak at 550 to 600 nm, whereas the naphthalocyanine green dye has an absorption peak at 650 to 700 nm.
This is because the compound has an absorption peak at m and 400 to 450 nm, so that it becomes a complementary color of a red-violet dye and efficiently achromatic.

Since the two-component film does not have an absorption peak in the light emitting region of the R and B light emitters, the color purity is improved and the contrast is improved. In addition, this makes it possible to achieve achromatic coloration of the film with the two kinds of the above dyes without using a large number of organic dyes, and to improve the film strength because the amount of the dye contained in the film is small.

The naphthalocyanine green dye of the present invention is represented by the following formula [1].

[0025]

Embedded image

[Where Me is Si, Cu, Ni, Pd,
VO, TiO, X is C _n H _{2n + 1} , CO ₂ C _n H
_2n + 1, with SC _n H _{2n + 1,} Y is OSiR ₃ (R is C
_n H _{2n + 1)} a and, n represents an integer, X, also those without a substituent Y] Further, since the organic pigments with quinacridones and naphthalocyanine dyes, film using conventional rhodamine organic dyes Is very good in light resistance.

Further, when conductive fine particles are contained in the film containing the dye, antistatic performance can be imparted. Furthermore, when a silica-based low refractive index film is formed on the film containing the dye and the conductive fine particles, an anti-reflection effect using light interference can be imparted. As described above, the three-layer structure can further improve the anti-reflection property.

In the case of a two-layer structure, if an electrically conductive organic layer is doped with an organic dye, the conductivity is reduced, and the antistatic performance is reduced. With the three-layer structure, the roles of wavelength selective absorption performance, antistatic performance, and antireflection performance can be shared, and an excellent surface treatment film can be formed without deteriorating each performance.

If metal conductive particles are used for the conductive layer, the surface resistance can be greatly reduced, and the problem of leakage electromagnetic waves can be dealt with. Hereinafter, the present invention will be described specifically with reference to examples.

[0030]

[Example 1] Silica (SiO ₂ ) 2.0% by weight, quinacridone (QN) 0.2% by weight, naphthalocyanine (Nc) 0.12% by weight, methanol 30% by weight,
A solution containing 50% by weight of water, 5% by weight of butanol, and 13% by weight of the balance (polymeric dispersant, hydrochloric acid, ketone solvent) was mill-dispersed for 13 hours by a ball mill containing zirconia beads.

The amount of the Nc dye was 0.20% by weight, 0.2% by weight.
A material having a weight ratio of 25% by weight was produced in the same manner. In addition,
As Nc, in the above formula [1], the substituent Me is S
Those having i and Y of C ₆ H ₁₃ and no X were used.

The solution thus obtained was spin-coated at 160 rpm on the face plate of a cathode ray tube, and then heat-treated at 160 ° C. for 20 minutes. The transmittance curve of this film is shown in FIG. In the figure, curve 1 is 0.12% by weight of Nc, curve 2 is 0.20% by weight, and curve 3 is 0.25% by weight.
3 is a transmittance curve of the film of FIG.

An absorption peak based on quinacridone appears at 578 nm, and an absorption peak based on a naphthalocyanine dye appears around 710 nm and 440 nm.

The luminous transmittance of the film of curve 1 is 76.47%, and the L, a * and b * values representing the color are L = 90.08 and a * = 4.7.
1, b * = − 3.68, which is an achromatic color.

The BCP value, which is an index of the contrast, is represented by (Brightness Contrast Performance, the reflection luminance decrease rate ΔRf, and the luminance decrease rate ΔB,
CP = ΔB√VΔRf) showed a very high value of 1.08. As the curves 2 and 3 show, when the Nc pigment increases, the BCP value decreases to 1.06 and 1.04. It turns out that the quantitative ratio of quinacridone (QN) and naphthalocyanine (Nc) is important.

The above ratio of QN to Nc is 1 <QN / Nc
<1 is a preferable value in the present invention.

Conventional three-color organic dye films (red dye rhodamine, blue dye B) prepared as comparative examples
50P, yellow dye DY50), L = 87.08, a * =
The color tone was relatively good at 4.50, b * =-3.50, but the BCP value was 1.04 and the contrast was low.

Further, when the strength of the film was examined by an eraser test (1 kg load), the film of the present invention survived 150 to 200 times of the sliding test, whereas the film of the conventional three-component system was 100%. The film strength was as low as about twice.

The light resistance was examined (at 365 nm, 4 nm).
mW / cm ² , tracking change in transmittance ΔT), and after 100 hours, the ΔT of the conventional dye-based film had changed by 50% or more, whereas the film of the present invention had a ΔT of about 2%, indicating light resistance. Was very good.

A similar wavelength selective absorption film could be obtained by using Nc shown in Table 1.

[0041]

[Table 1]

Example 2 Conductive fine particles ATO (Sn
O ₂ (Sb)) 1.28% by weight, silica (SiO ₂ ) 1.0% by weight, quinacridone (QN) 0.2% by weight, naphthalocyanine (Nc) 0.12% by weight, methanol 30% by weight, water A solution containing 50% by weight, 5% by weight of butanol, and 13% by weight of the balance (polymeric dispersant, hydrochloric acid, ketone solvent) was mill-dispersed by a ball mill containing zirconia beads for 13 hours. This solution was spin-coated at 160 rpm on the faceplate of a cathode ray tube,
For 20 minutes.

On this film surface, 1.00% by weight of SiO ₂ sol
Is spin-coated at 160 rpm on the surface of a cathode ray tube face plate in the same manner,
Heat treated for 0 minutes. FIG. 2 shows a schematic cross-sectional view of the surface treatment film thus manufactured. In the figure, 4 is an organic dye layer, 5
Is an ATO particle, and 6 is a low refractive index SiO ₂ layer.

The organic dye layer containing the ATO particles has a high refractive index.
Anti-reflection performance is exhibited. In addition, since the ATO particles are conductive, antistatic performance is exhibited. The surface resistance of this film was 8 × 10 ⁹ Ω / □, and the surface reflectance was 1.5%.

The transmittance performance and surface color of the film were L = 8.
The color was relatively good at 7.08, a * = 4.50, b * =-3.50, the BCP value was high at 1.09, and the contrast was also good. This film had an antireflection function and an antistatic function, and also had a good wavelength selective absorption function.

As conductive fine particles, instead of ATO, IT
When O (In ₂ O ₃ (Sn)) is used, the surface resistance is 5 × 10 ⁶
Ω / □ and a surface reflectance of 1.2% were obtained.

Example 3 2.0% by weight of silica (SiO ₂ ), 0.2% by weight of quinacridone (QN), 0.12% by weight of naphthalocyanine (Nc), 30% by weight of methanol, 50% by weight of water, A solution containing 5% by weight of butanol and 13% by weight of the balance (polymeric dispersant, hydrochloric acid, ketone solvent) was mill-dispersed for 13 hours by a ball mill containing zirconia beads.

This solution was spin-coated on the face plate of a cathode ray tube at 160 rpm, and then heat-treated at 160 ° C. for 20 minutes.

On the surface of this film, an Ag ultrafine particle dispersion sol 1.
00% by weight was spin-coated on the surface of a CRT face plate in the same manner as described above, and then 0.90% by weight of a SiO ₂ sol was spin-coated on the film surface, and then at 160 ° C. for 20 minutes. Heat treated. FIG. 3 shows a cross-sectional structure of this film. In the figure, 7 is an organic dye layer, 8 is a metal (Ag) conductive layer, and 9 is a low refractive index SiO ₂ layer.

The surface resistance of this film was 8 × 10 ² Ω / □, and the surface reflectance was 0.89%. The transmittance is 45%
(575 nm). Since the surface resistance of this film is very low, it is possible to remove leakage electromagnetic waves around the CRT.

The transmittance performance and surface color of the film were L = 67.0.
8, a * = 4.45, b * =-3.61 and the color was relatively good, the BCP value was as high as 1.10, and the contrast was also good. For the metal-based antistatic film, Ag
In addition, a display device having similar performance was obtained using a film of Au, Pt, Pd, or an alloy thereof.

Although a cathode ray tube is used for the display device in the embodiment, similar effects can be obtained if the display device is a self-luminous display device such as an EL or PDP.

[0053]

As described above, according to the present invention, the type of organic dye contained in the wavelength selective absorption film of the display device can be reduced to two types, red and green.

A quinacridone dye is used as a red dye, and a naphthalocyanine dye is used as a green dye which is a complementary color thereof.
In terms of absorption spectrum, this naphthalocyanine dye can efficiently achromaticize a quinacridone dye as a red dye. Therefore, a wavelength selective absorption film having good color purity and good contrast characteristics can be obtained.

Further, since the amount of dye in the film can be reduced,
The strength of the film can be improved. Further, by stacking the conductive fine particle layer, an antistatic performance and an antireflection function can be provided.

[Brief description of the drawings]

FIG. 1 is a transmittance curve diagram of a selective absorption film used in an example.

FIG. 2 is a schematic cross-sectional view of a reflection-prevention wavelength-selective absorption film formed by anti-reflection.

FIG. 3 is a schematic sectional view of a wavelength selective absorption film having a three-layer structure for preventing reflection and electrification.

[Explanation of symbols]

1 ... Nc 0.12% by weight of the transmittance curve of the membrane, 2 ... Nc 0.1.
20% by weight membrane transmittance curve, 3 ... 0.2% Nc by weight
Transmittance curve of the film of 4, 4 ... organic dye layer, 5 ... ATO particles,
6: Low refractive index SiO ₂ layer, 7: Organic dye layer, 8: Metallic (Ag) conductive layer, 9: Low refractive index SiO ₂ layer.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Daigoro Kamoto 7-1-1, Omikacho, Hitachi City, Ibaraki Prefecture Within Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Keiro Ishikawa Omikamachi, Hitachi City, Ibaraki No. 1-1, Hitachi, Ltd.Hitachi Research Laboratories Hitachi Research Laboratories (72) Inventor Noriuchi Uchiyama 3300 Hayano, Mobara-shi, Chiba Pref.Electronic Devices Division, Hitachi, Ltd. F-term in Hitachi Device Engineering Co., Ltd. (Reference) 2H048 CA04 CA09 CA15 CA19 CA24 CA25 4F100 AA20H AA33B AB24B AB40B AH00B AR00B AR00C AR00D AS00A BA02 BA04 BA07 BA10A BA10C BA10D CA13B CA30B DE00B DE01H EJ64BG00 JJBJM00 JE00J01B 5C032 AA02 DD02 DE01 DF03 DG01 DG02 DG04 EE03 EF01 EF05

Claims (6)

[Claims] 1. A display device having a surface treatment film formed on a display surface, wherein the surface treatment film contains an organic dye,
0-600 nm, 650-700 nm and 400-4
A display device having an absorption peak at 50 nm. 2. The display device according to claim 1, wherein the organic dye is a quinacridone dye or a naphthalocyanine dye. 3. The display device according to claim 1, wherein the surface treatment film includes conductive fine particles. 4. The method according to claim 1, wherein the conductive fine particles are ATO, ITO,
The display device according to claim 3, wherein the display device includes at least one of Ag, Pd, Pt, and Au. 5. The display device according to claim 4, wherein the surface treatment film has a low refractive index film as an upper layer. 6. The display device according to claim 1, wherein the high-refractive-index film and the low-refractive-index film are sequentially stacked on the surface treatment film.