JP2000105541A - Display front panel - Google Patents

Abstract

(57) [Problem] To provide a display front plate which is used by being installed on the front surface of a projection television receiver, a liquid crystal display device, a plasma display, or the like, and has good image contrast and color reproducibility. SOLUTION: The light transmittance at a wavelength of 450 nm is 52 wavelengths.
A display front plate, wherein the light transmittance at a wavelength of 525 nm is larger than the light transmittance at a wavelength of 630 nm, the light transmittance being larger than 5 nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a front panel of a projection television receiver, a liquid crystal display device, a plasma display and the like. In particular, the present invention relates to a display front plate having good image contrast and color reproducibility. Further, the present invention relates to a display front plate which also has a performance of preventing interference due to near infrared rays and electromagnetic waves emitted from a plasma display.

[0002]

2. Description of the Related Art In recent years, various display devices have been required to improve image contrast and faithful color reproduction performance for the purpose of improving image quality. It is known that absorption of external light and reduction of reflection lead to improvement of contrast in order to improve the image quality. The display front plate absorbs visible light other than the red / green / blue emission spectrum of the image light source. Is known to be effective. Further, it is known that, in a plasma display, orange light emission exists near a wavelength of 580 nm in addition to the red / green / blue light emission spectrum, and this light emission reduces image contrast and color reproducibility. Further, in a plasma display, the color reproducibility of an image is poor because the emission intensity of red / green / blue is different.

In response to these problems, Japanese Patent Publication No. 5-2709
No. 8 discloses a transmission screen having a wavelength of 500 to 500.
Colorant that absorbs light in the 600 nm region and wavelength 520n
There is disclosed a transmission screen device in which a compound having a spectral characteristic with a maximum transmittance near m is blended. Also, JP-A-9-241520 and JP-A-10-128888 disclose a transparent resin and an absorbance in a specific wavelength range of 0.0.
It is composed of a resin composition comprising at least one or more light-absorbing compounds, and has a total light transmittance of 50 to 90.
%, And the spectral light transmittance in the visible light wavelength range of 430 to 650 nm is 60 to 85 at 430 to 480 nm.
%, 50-70% at 530-580 nm, 590-64
A selective wavelength-absorbing composite resin panel molded article having a range of 50 to 85% at 0 nm is disclosed. W098 / 2
3980 discloses a bandpass filter to which a plurality of dyes for improving the contrast of a color display are added.

[0004]

However, according to the methods described in Japanese Patent Publication No. 5-27098, Japanese Patent Application Laid-Open No. 9-241520, Japanese Patent Application Laid-Open No. 10-128898, etc., a red / green / blue light emission vector is used. Other than that, the degree of absorption of visible light is small, the effect of reducing reflection from surrounding light and improving the contrast of an image is insufficient. Further, WO98 / 23980 does not describe the wavelength and transmittance, and the transmittance near the wavelength of 580 nm is high, so that the effect of improving the image contrast and color reproducibility is insufficient. Also, none of these methods can correct the red / green / blue light emission intensity of the display, and the improvement of the color reproducibility of the image on the display is insufficient.

In view of such circumstances, the present inventor has conducted intensive studies on a front plate of a display having good image contrast and color reproducibility. As a result, the light transmittance of the front plate at a wavelength of 450 nm is larger than the light transmittance of a wavelength of 525 nm. ,
By making the light transmittance at a wavelength of 525 nm larger than the light transmittance at a wavelength of 630 nm, a display front plate having good image contrast and color reproducibility can be obtained, and the light transmittance at a wavelength of 580 nm is reduced to 60% or less. As a result, they have found that a front panel having good image contrast and color reproducibility and also having a performance of preventing obstacles due to near infrared rays can be obtained, and the present invention has been completed.

[0006]

That is, the present invention is as follows. (1) A display front plate, wherein a light transmittance at a wavelength of 450 nm is larger than a light transmittance at a wavelength of 525 nm, and a light transmittance at a wavelength of 525 nm is larger than a light transmittance at a wavelength of 630 nm. (2) The transmittance of the front panel with respect to light emission of the display is
The display front plate according to the above (1), which is larger than the total light transmittance of the front plate. (3) The light transmittance at a wavelength of 580 nm is 60% or less, the light transmittance at a wavelength of 490 nm is 80% or less, and the wavelength is 670 nm.
The display front plate according to the above (1) or (2), wherein the light transmittance is 80% or less and the total light transmittance is 40% or more. (4) The display front plate according to (1), (2)) or (3), wherein the light transmittance at a wavelength of 580 nm is 60% or less. (5) The light transmittance at a wavelength of 850 nm to 950 nm is 15
% Of the display front panel according to (1), (2), (3) or (4). (6) The above (1), (2), (3), (4) or the above (1) having at least one of a hard coat layer, an electromagnetic wave shielding layer, and an antireflection layer on the surface or inside of the front plate. (5) The display front panel according to (5).

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The front plate of the present invention is a film or a sheet installed on the front of a display device. The size can be arbitrarily selected according to the screen size of the display device. The thickness can be arbitrarily selected, but is generally about 0.01 to 10 mm.

The front plate is made of glass or transparent resin. Examples of the transparent resin include acrylic resins, polycarbonate resins, polyester resins, cellulose resins such as triacetyl cellulose and diacetyl cellulose, and styrene resins. Above all, light transmittance,
Acrylic resins containing acrylates and methacrylates as main components are suitable from the viewpoint of weather resistance and the like. In addition, an optical film or a sheet provided with a polarization property is also exemplified.

In the front plate of the present invention, the light transmittance at a wavelength of 450 nm is larger than the light transmittance at a wavelength of 525 nm, and the light transmittance at a wavelength of 525 nm is larger than the light transmittance at a wavelength of 630 nm. It is known that when comparing the emission intensity of red / green / blue in a display device, especially a plasma display, the intensity is often strong in the order of red>green> blue. , (Wavelength 450 nm
> (Light transmittance at wavelength of 525 nm)>
(Light transmittance at a wavelength of 630 nm),
This is for correcting the emission intensity ratio of red / green / blue, thereby improving the color reproducibility of the image. Above all, when the light transmittance of the front plate at a wavelength of 450 nm is 1, the wavelength is 5
25 nm light transmittance 0.80 to 0.95, wavelength 63
It is preferable that the light transmittance at 0 nm is in the range of 0.65 to 0.90, because the color reproducibility of the image is further improved. In this case, the wavelengths are 450 nm, 525 nm, and 630.
The light transmittance in nm is preferably close to the reciprocal of the blue / green / red emission intensity ratio of the display. For example, if the display has a blue / green / red emission intensity ratio of 1: 1.
2: If 1.3, the wavelength of the front plate is 450 nm, 525 n.
m, the ratio of light transmittance at 630 nm is 1: 0.83: 0.
It is good to be about 77.

Further, the front plate of the present invention absorbs as much external light as possible, absorbs visible light other than the red / green / blue light emission vector of the image light source, and improves the image contrast and color reproducibility. Preferably, the transmittance of the front panel for the light emission of the display is larger than the total light transmittance of the front panel, and preferably, the transmittance of the front panel for the light emission of the display is about 5% or more larger than the total light transmittance of the front panel. preferable. The total light transmittance in this case is the total light transmittance of the front plate measured by JlSK7361. Further, the transmittance of the front panel for light emission of the display is calculated by the following equation from the luminance when the front panel is not mounted and the luminance when the front panel is mounted when a white screen is displayed on the display. (Transmittance of front panel for light emission of display) = (Brightness when front panel is attached / Brightness when front panel is not attached) × 100

Further, the light transmittance of the front plate at a wavelength of 490 nm is 80% or less, and the light transmittance at a wavelength of 580 nm is 60%.
Hereinafter, when the light transmittance at a wavelength of 670 nm is 80% or less and the total light transmittance is 40% or more, light other than light emission of a display is efficiently absorbed, and the contrast of an image is improved. Is the wavelength of 490 nm
Has a light transmittance of 70% or less, a light transmittance of 50% or less at a wavelength of 580 nm, and a light transmittance of 70% or less at a wavelength of 670 nm.
The following is more preferred. In the above case, the wavelength 5
When the light transmittance at 80 nm is 60% or less, and more preferably 55% or less, unnecessary light emission at around 580 nm is absorbed when the front plate is used for a plasma display,
The color reproducibility of the image is improved.

In order to achieve the light transmittance of the front plate of the present invention, a light absorbing compound is added. (Light transmittance at a wavelength of 450 nm)> (Light transmittance at a wavelength of 525 nm)> (Light transmittance at a wavelength of 630 nm), preferably 45
When the light transmittance at 0 nm is 1, the wavelength is 525 nm.
In order to obtain a light transmittance of 0.80 to 0.95 and a light transmittance at a wavelength of 630 nm of 0.65 to 0.90, a light-absorbing compound having a maximum absorption wavelength in the range of 400 to 550 nm, This can be achieved by appropriately combining a light absorbing compound having an absorption wavelength in the range of 550 to 620 nm and a light absorbing compound having a maximum absorption wavelength in the range of 620 to 900 nm. As these light absorbing compounds, known dyes such as anthraquinone compounds, azo compounds, phthalocyanine compounds, naphthalocyanine compounds, dithiol complex compounds, and cyanine compounds can be used.

The wavelengths of 450 nm, 525 nm and 630
The light transmittance of the display on the front panel is set to be larger than the total light transmittance of the front panel while maintaining the light transmittance of the front panel in the above range. In order that the transmittance is 80% or less, the light transmittance at a wavelength of 670 nm is 80% or less, and the total light transmittance is 50% or more, the maximum absorption wavelength and absorption width of these light-absorbing compounds are taken into consideration, Select an appropriate light absorbing compound. That is, among these, a light-absorbing compound having a maximum absorption wavelength near the wavelengths of 490 nm, 580 nm and 670 nm is added, and
It selectively reduces the light transmittance at 90 nm, 580 nm and 670 nm.

As these light absorbing compounds, commercially available dyes and the like can be used, and examples thereof include the following. Examples of the compound having a maximum absorption wavelength in the range of 400 to 550 nm include a dye Sumipl manufactured by Sumitomo Chemical Co., Ltd.
ast® Red3B, Sumikaron
(Registered trademark) RedE-FBL, Sumikaron
(Registered trademark) Red S-GG, Sumikaron
(Registered trademark) S-BWF, dye Diaresine (registered trademark) Red Z manufactured by Mitsubishi Chemical Industry Co., Ltd., dye O1eosol (registered trademark) Re manufactured by Taoka Chemical Industry Co., Ltd.
dBB, dye Cromophta manufactured by Ciba-Geigy
l (R) Brown 5R, a dye Paliogen (R) Red K-391 from BASF.
HD. As a compound having a maximum absorption wavelength of 550 to 600 nm, a dye Sumik manufactured by Sumitomo Chemical Co., Ltd. is used.
aron (R) Bordeaux SE-B
L, Sumikaron (registered trademark) Violet
S-4RL, Sumikaron (R) Vio
let E-2RL, Sumikaron (registered trademark)
Blue S-3RF, dyes NK4526 and NK4670 manufactured by Japan Photographic Dye Laboratories, and the like. Examples of the compound having a maximum absorption wavelength in the range of 600 to 900 nm include Sumikaron (registered trademark) Turquoise Blue S-GL manufactured by Sumitomo Chemical Co., Ltd., dye IR-750 manufactured by Nippon Kayaku, and Mitsui Chemicals. Near-infrared absorbers manufactured by Kogyo Co., Ltd. SlR-114, SlR-159, PA
-1005, PA-1006, Nippon Shokubai's near-infrared absorbing agent EEXCOLOR IR-1, IR-12, IR-13, VS-4, 601W, 803K, 604K, 802
K, 803K, 805K, 808K, 810K, 901
B, 902B, NQM near infrared rays manufactured by Fuji Photo Film Co., Ltd., IRF-700, IRF-770, IRF-
880. Among these, the light absorbing compounds having absorption near the wavelength of 580 nm necessary to make the light transmittance at the wavelength of 580 nm 60% or less include dyes NK4526, NK4670, NK4675 and NK4675 manufactured by Nippon Koso Pigment Research Institute.
Cyanine compounds such as NK2610 and NK4424 are preferred.

The amount of the light absorbing compound to be added depends on the light absorbing ability, but may be in the range of 0.1 to 1.0 m ² per front plate.
The range is from 0001 to 10 g. It is necessary to adjust the amount of addition depending on the desired performance and the thickness of the front plate. Further, a light absorbing compound having a maximum absorption wavelength other than the above-described maximum absorption wavelength may be added as long as the purpose is not impaired.

When a display to be used is a plasma display, it is known that near infrared rays emitted from the display impair various remote control devices and the like. In order to absorb this near infrared ray, a wavelength of 85
The average transmittance from 0 nm to 950 nm is preferably 15% or less. In order to achieve this, in addition to the above-mentioned compounds having a maximum absorption wavelength in the range of 650 to 900 nm, aminium-based compounds, anthraquinone-based compounds, phthalocyanine-based compounds, naphthalocyanine-based compounds, and dithiol having absorption in the near infrared region Uses complex compounds, polymethine compounds, pyrylium compounds, thiopyrylium compounds, squararylium compounds, croconium compounds, azurenium compounds, tetradehydrocholine processed products, triphenylmethane compounds, diimmonium compounds, etc. I can do it. Also EP0838
A resin composition containing a phosphorus atom and a copper atom as shown in 475A2 may be used. Alternatively, a method of forming a multilayer film containing silver on the surface may be used.

The following methods can be used to prepare the front plate of the present invention by adding these light absorbing compounds to a film or sheet. (1) A method in which a light-absorbing compound is melt-kneaded into a transparent resin and a film or sheet is formed by a known extrusion molding method, injection molding method, or press molding method. (2) After dissolving and dispersing the light-absorbing compound in the monomer component as a raw material of the transparent resin, it is polymerized by a known casting polymerization method,
How to make a film or sheet. (3) A method in which a resin layer containing a light-absorbing compound is formed on the surface of a sheet or a film using a known coating method. (4) A method of dyeing a film or sheet with a light-absorbing compound using a known dyeing method.

The front plate may be a single layer of a film or a sheet, a laminate of a plurality of layers, or a film or sheet containing a light absorbing compound obtained by the above method, containing no light absorbing compound. The front plate may be manufactured by laminating with glass, a film, a sheet, or the like.

The front plate of the present invention may have a light diffusing agent, a coloring agent, a reinforcing agent, a filler, a release agent, a stabilizer, an ultraviolet absorber, an antioxidant, an antistatic agent, a flame retardant, if necessary. It is also possible to add agents and the like.

A hard coat layer, an electromagnetic wave shielding layer, and an antireflection layer are formed on the front plate of the present invention on the surface or inside as necessary.

The surface of the transparent substrate, particularly the surface on which the antireflection layer is formed, is easily damaged during use. Therefore, it is preferable to increase the hardness of the surface by forming a hard coat layer. Known hard coat layers used for this purpose are used as the hard coat layer. For example, a cured film obtained by polymerizing and curing a coating agent containing a polyfunctional monomer as a main component can be mentioned. Specifically, a polyfunctional polymerizable compound obtained by combining two or more acryloyl groups and methacryloyl groups such as urethane (meth) acrylate, polyester (meth) acrylate, and polyether (meth) acrylate is used as an active substance such as an ultraviolet ray and an electron beam. And a layer obtained by crosslinking and curing a silicon-based, melamine-based, or epoxy-based crosslinkable resin material by heat.

As a method for forming a hard coat layer, first, a coating agent is used in a usual coating operation, that is, spin coating, dip coating, roll coating, gravure coating, curtain flow coating. , By a bar coating method or the like. Subsequently, it is cured by a method according to the used raw material. At this time, the coating agent may be diluted with various solvents in order to facilitate coating and to easily adjust the thickness of the coating film. In order to cure the applied coating agent, a method of performing thermal polymerization by heating and heating, or photopolymerizing by irradiation of a collective energy ray such as an ultraviolet ray or an electron beam is used.

The thickness of the hard coat layer is not particularly limited, but is preferably 1 to 20 μm. If the thickness is less than 1 μm, an interference pattern of light appears due to the influence of the upper antireflection layer, which is not preferable in appearance. On the other hand, if the thickness exceeds 20 μm, the coating film is undesirably cracked, for example, in terms of film strength. In order to improve the adhesion between the transparent substrate and the hard coat layer, an adhesive layer may be provided between the transparent substrate and the hard coat layer. The adhesive layer may be a known one used for this purpose.

The front plate of the present invention is preferably provided with a conductive layer having enhanced electric conductivity in order to shield electromagnetic waves generated from the display. As the conductive layer,
Examples include meshes made of conductive fibers, coatings of metal oxides such as zinc oxide, tin oxide, and indium oxide, and coatings and multilayer coatings of metals such as gold, silver, copper, and aluminum.

The front plate of the present invention is preferably provided with antireflection layers on both surfaces of a transparent substrate for improving visibility. The antireflection layer is a multi-layer antireflection film combining a low refractive index material such as magnesium fluoride and silicon oxide and a high refractive index material such as titanium oxide, tantalum oxide, tin oxide, indium oxide, zirconium oxide and zinc oxide. A single-layer antireflection film mainly containing a fluorine low-refractive-index resin is exemplified.

[0026]

When the front panel of the present invention is used as a front panel of a projection television, a liquid crystal display device, or a plasma display, the contrast and color reproducibility of an image are good and the contrast and color reproducibility of an image are good. It is good and has the ability to prevent near infrared and electromagnetic interference.

[0027]

The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples. The evaluation was performed by the following method. Total light transmittance: measured using a transmission / reflectometer HR-100 manufactured by Murakami Color Research Laboratory according to J1SK7361. Transmittance for light emission of display on front panel; Plasma display PDS-P100 manufactured by Fujitsu General Limited
A white screen was displayed at 0 (no front panel), and the luminance was measured using PR650 manufactured by Photo Research Inc. with and without the front panel, and calculated using the following equation. (Transmittance of front panel for light emission of display) = (Brightness when front panel is attached / Brightness without front panel) × 100 Light transmittance at specific wavelength; Hitachi self-recording spectrophotometer U3
The measurement was performed using Model 410. Image contrast and color reproducibility; images were displayed on a plasma display PDS-P1000 (without front panel) manufactured by Tomi-Tsutoshi General Co., Ltd., and were further observed by 10 persons with the indoor fluorescent lamp turned on. Compared to the case where the front plate was not attached, the judgment was made as to whether or not there was an effect of improving the color reproducibility and contrast of the image when attached. Result is
The number of people out of 10 was judged to have an improvement effect. Remote control test: Plasma display PDS-P1000 manufactured by Fujitsu General Limited with a front panel installed at a position 15 m diagonally forward and 10 m away from home TV
The mold was placed and the image was displayed. A remote control signal (signal wavelength: 950 nm) is sent to the home TV from a place 3 m away from the home TV at an angle of 15 degrees diagonally forward to check if it responds normally, and bring the plasma display device closer to the home TV. And measured the distance at which it did not respond normally. If the near-infrared ray generated from the display device cannot be shielded, the remote control will be hindered and will not respond or malfunction. The shorter the distance at which the system does not respond normally, the better the remote control failure prevention function.

Example 1 Sumikaron, a dye manufactured by Sumitomo Chemical Co., Ltd.
(Registered trademark) Violet S-4RL (maximum absorption wavelength: 550 nm) 0.000075 parts by weight, Sumika
ron (registered trademark) S-GG (maximum absorption wavelength: 500
nm), 0.0006 parts by weight, Sumikaron (registered trademark) Turquoise Blue S-GL (maximum absorption wavelength: 670 nm) 0.0006 parts by weight, and azobisisobutyronitrile 0.1% as a radical polymerization initiator.
One part by weight was dissolved in 100 parts by weight of methyl methacrylate. This solution was poured into a polymerization cell composed of a polyvinyl chloride gasket and two glass plates, and was heated at 70 ° C. for 5 hours.
Heat polymerization was performed at 120 ° C. for 1 hour to obtain a 3 mm sheet.
The obtained sheet was used as a front plate as it was. The front panel had a total light transmittance of 67% and a light transmittance of the display of 75%. Table 1 shows the light transmittance of each wavelength. Assuming that the transmittance at a wavelength of 450 nm is 1, a wavelength of 5
The transmittance at 25 nm is 0.94, and the transmittance at 630 nm is 0.89. Table 2 shows the evaluation results of image contrast and color reproducibility.

Example 2 Hydroxide was added to a monomer mixture consisting of 74% by weight of methyl methacrylate, 4% by weight of methacrylic acid, 4% by weight of neopentyl glycol dimethacrylate, and 18% by weight of a compound represented by the following structural formula. 1.2 parts by weight of copper, Sumikaron (registered trademark) S-GG (maximum absorption wavelength: 500 nm), a dye manufactured by Sumitomo Chemical Co., Ltd. 0.00
05 parts by weight, NK4 which is a dye manufactured by Japan Photosensitive Dye Laboratories
526 (maximum absorption wavelength: 585 nm) 0.0005 parts by weight, t-butylperoxy- as a radical polymerization initiator
0.4 parts by weight of 2-ethylhexanoate was dissolved. This solution was poured into a polymerization cell consisting of a polyvinyl chloride gasket and two glass plates, and the solution was added at 50 ° C. for 12 hours.
Heat polymerization was carried out at 0 ° C. for 2 hours to obtain a sheet having a thickness of 3 mm.
This was used as it was as a front panel. The total light transmittance of this front plate was 75%, and the transmittance for light emission of the display was 81%. Table 1 shows the light transmittance of each wavelength. Assuming that the transmittance at a wavelength of 450 nm is 1, a wavelength of 525
The transmittance at 0.9 nm is 0.94, and the transmittance at 630 nm is 0.79. Table 2 shows the evaluation results of the image contrast, color reproducibility, and remote control test.

[0030]

Embedded image CH ₂ = C (CH ₃ ) COO- [CH ₂ CH (CH ₃ ) O] _5.5 -P (O) (OH) ₂

Example 3 0.0005 parts by weight of NK4526 (maximum absorption wavelength: 580 nm), a dye manufactured by Nippon Kogaku Dye Laboratories, EEX Color 901K, a near infrared absorbing agent manufactured by Nippon Shokubai Co., Ltd.
(Maximum absorption wavelength: 900 nm) 0.0025 parts by weight,
902K (maximum absorption wavelength: 950 nm) 0.0075 parts by weight, 805K (maximum absorption wavelength: 820 nm) 0.00
25 parts by weight of azobisisobutyronitrile as a radical polymerization initiator and 0.1 part by weight of methyl methacrylate
Dissolved in 00 parts by weight. This solution was poured into a polymerization cell composed of a polyvinyl chloride gasket and two glass plates, and heated and polymerized at 70 ° C. for 5 hours and at 120 ° C. for 1 hour.
mm sheet was obtained. This was used as it was as a front panel. The total light transmittance is 50%, and the transmittance for light emission of the display is 56%. Table 1 shows the light transmittance of each wavelength.
Shown in Assuming that the transmittance at 450 nm is 1, the transmittance at 525 nm is 0.87, and the transmittance at 630 nm is 0.79. Table 2 shows the evaluation results of the image contrast, color reproducibility, and remote control test.

Comparative Example 1 A commercially available acrylic resin plate (methacrylic resin manufactured by Sumitomo Chemical Co., Ltd .: SUMIPEX (registered trademark) 919, plate thickness 2)
mm) was used as it was as a front plate. The total light transmittance was 73%, and the transmittance for light emission of the display was 65%. Table 1 shows the evaluation results for each wavelength. If the transmittance at 450 nm is 1, the transmittance at 525 nm is 1.08,6.
The transmittance at 30 nm is 1.18. Table 2 shows the evaluation results of image contrast and color reproducibility.

[0033]

[Table 1]

[0034]

[Table 2]

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) // G02B 5/20 G02B 5/20

Claims (8)

[Claims] 1. The light transmittance at a wavelength of 450 nm is 52
A display front plate, wherein the light transmittance at a wavelength of 525 nm is larger than the light transmittance at a wavelength of 630 nm, the light transmittance being larger than 5 nm. 2. When the light transmittance at a wavelength of 450 nm is 1, the light transmittance at a wavelength of 525 nm is 0.80 to 0.9.
5. Light transmittance at a wavelength of 630 nm is 0.65 to 0.90
2. The display front panel according to claim 1, wherein 3. The display front panel according to claim 1, wherein a transmittance of the front panel for light emission of the display is larger than a total light transmittance of the front panel. 4. The light transmittance at a wavelength of 490 nm is 80% or less, the light transmittance at a wavelength of 580 nm is 60% or less, and the wavelength is 6%.
The light transmittance at 70 nm is 80% or less, and the total light transmittance is 40% or more.
Display front panel described in the item. 5. The display front plate according to claim 1, wherein a light transmittance at a wavelength of 580 nm is 60% or less. 6. The display front plate according to claim 1, wherein a light transmittance at a wavelength of 850 nm to 950 nm is 15% or less. 7. The display front plate according to claim 1, further comprising at least one of a hard coat layer, an electromagnetic wave shielding layer, and an antireflection layer on the surface or inside the front plate. 8. The display front plate according to claim 1, wherein the display is a plasma display.