JP2001305335A - Liquid crystal display device members - Google Patents

Abstract

(57) [Problem] To provide a member for a liquid crystal display device, which does not cause a problem even when a high luminance type cold cathode tube is used as a light source. A wavelength of 200 to 4 in a normal direction of a light incident surface.
An average transmittance (a) of light of 00 nm is 20% or less;
And the average transmittance (b) of light having a wavelength of 400 to 800 nm.
A member for a liquid crystal display device, wherein the ratio (a / b) of the average transmittance (a) of light having a wavelength of 200 to 400 nm with respect to is not more than 0.3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a member for a liquid crystal display device. Specifically, a light guide plate used for a liquid crystal display device,
The present invention relates to optical members such as a light diffusion sheet, a prism sheet, a liquid crystal cell, a polarizing sheet, and a front panel.

[0002]

2. Description of the Related Art Liquid crystal display devices are widely used in PC monitors, display units of car navigation systems, thin TVs, and the like. 2. Description of the Related Art A liquid crystal display device generally has an optical system composed of members such as a light guide plate, a light diffusion sheet, a prism sheet, a liquid crystal cell, a polarizing sheet, and a front panel using a cold cathode tube as a light source. Conventionally, the study of each member used in liquid crystal display devices has focused on improving the brightness by efficiently emitting the light emitted from the cold cathode tube to the front surface, and on reducing the weight and size of the liquid crystal display device. Have been. For example, Japanese Unexamined Patent Publication No. Hei 6-301034 describes that the weight can be reduced by integrating a lamp fixing plate having an engagement hole and a printed acrylic light diffusing plate with a protruding pin. Also, Japanese Patent Application Laid-Open No. 6-95107 describes that the luminance can be improved by combining a plurality of light diffusion sheets.

On the other hand, as a cold cathode tube used as a light source of a liquid crystal display device, a high efficiency and high brightness type cold cathode tube has been developed in recent years.
The development of large objects with a high brightness exceeding 14 inches has begun. However, when a high-brightness type cold-cathode tube is incorporated as a light source in a liquid crystal display device, if a conventional optical member for a liquid crystal display device is used, a member such as a housing of a backlight unit around the optical member or a liquid crystal display device There is a high possibility that an article such as a decorative article in the vicinity is deteriorated, and further, a remote control of another apparatus placed around the liquid crystal display device is caused to malfunction, thereby causing a malfunction.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a member for a liquid crystal display device which does not cause any trouble even when a high-brightness type cold-cathode tube is used as a light source. It is in.

[0005]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a member having a specific light transmission characteristic is suitable for the above object, and have completed the present invention. That is, in the present invention, the wavelength of 200 to
The average transmittance (a) of light having a wavelength of 400 nm is 20% or less, and the ratio (a) of the average transmittance (a) of light having a wavelength of 200 to 400 nm to the average transmittance (b) of light having a wavelength of 400 to 800 nm. / B) is a member for a liquid crystal display device having a value of 0.3 or less.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The member of the present invention is a member for a liquid crystal display device, and specifically, for example, an optical member in a liquid crystal display device such as a light guide plate, a light diffusion sheet, a prism sheet, a liquid crystal cell, a polarizing sheet, and a front panel. is there. Usually, a cold cathode tube is used as a light source of the liquid crystal display device, and the tube diameter of the cold cathode tube used is usually about 1 to 5 mmφ.

As for the arrangement of the light source and each member, there are a direct type and an edge light type. In the direct type, for example, as shown in FIG. The light diffusion sheet 3, the prism sheet 4, the polarizing sheet 5, the liquid crystal cell 6, the polarizing sheet 5, and the front panel 7 are arranged in this order. On the other hand, in the edge light type, as shown in FIG. 2, for example, the cold cathode tubes 2 are arranged at the edges of the light guide plate 8, the reflection sheet 1 is arranged below the light guide plate 8, and the light diffusion The sheet 3, the prism sheet 4, the polarizing sheet 5, the liquid crystal cell 6, the polarizing sheet 5, and the front panel 7 are arranged in this order.

As the material used for the substrate of the member of the present invention, a material having high transparency is preferable, and examples thereof include a resin such as a methyl methacrylate resin, a styrene resin, and a polycarbonate resin, and glass. Among them, a methyl methacrylate resin is preferable.

Here, the methyl methacrylate resin is
Methyl methacrylate as a monomer constituting the resin is 5
Polymethyl methacrylate, which is a polymer containing 0% by weight or more, and is substantially a homopolymer of methyl methacrylate,
Examples of the copolymer include 50% by weight or more of methyl methacrylate and 50% by weight or less of an unsaturated monomer copolymerizable therewith.

The unsaturated monomers copolymerizable with methyl methacrylate in the methyl methacrylate resin include, for example, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, methacrylic acid 2 -Ethylhexyl,
Methacrylates such as 2-hydroxyethyl methacrylate; methyl acrylate, ethyl acrylate,
Acrylates such as butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate; unsaturated acids such as methacrylic acid and acrylic acid; styrene; Examples thereof include α-methylstyrene, acrylonitrile, methacrylonitrile, maleic anhydride, phenylmaleimide, and cyclohexylmaleimide. If necessary, two or more of these may be used. Further, the copolymer may have a glutaric anhydride unit or a glutarimide unit.

The styrene-based resin is a polymer containing 50% by weight or more of styrene as a monomer constituting the resin, such as polystyrene which is a homopolymer of styrene or 50% by weight or more of styrene. And a copolymer comprising 50% by weight or less of an unsaturated monomer copolymerizable therewith.

Examples of the unsaturated monomer copolymerizable with styrene in the styrene resin include, in addition to methyl methacrylate, unsaturated monomers copolymerizable with methyl methacrylate in the above-mentioned methyl methacrylate resin except styrene. Monomers are used, and two or more of them can be used as necessary.

The polycarbonate resin can be usually obtained by a reaction between a bishydroxyaryl compound and phosgene or a reaction between a bishydroxyaryl compound and a carbonate such as diphenyl carbonate. Representative bishydroxyaryl compounds include bisphenol A (2,2-bis (4-hydroxyphenyl) propane).

As the glass, silica glass or phosphate glass is usually used. Glass includes soda ash, calcium carbonate, slaked lime, borax, hydrous boric acid, potassium carbonate,
Aluminum hydroxide, aluminum oxide, feldspar, lead red,
A trace amount of litharge, zinc oxide, barium carbonate, lithium carbonate, magnesium oxide, titanium oxide, zirconium oxide, iron oxide and the like may be contained. Among these compounds, carbonates and hydroxides may be changed to oxides.

The member of the present invention has an average transmittance (a) of light having a wavelength of 200 to 400 nm in a direction normal to the light incident surface.
But not more than 20%, preferably not more than 15%. If the average transmittance (a) of light having a wavelength of 200 to 400 nm exceeds 20%, peripheral members and articles may be affected by discoloration or the like. The lower limit of the average transmittance (a) of light having a wavelength of 200 to 400 nm is not particularly limited, but is usually 0.01% or more from the viewpoint of suppressing the color tone of transmitted light from becoming yellow.

The normal direction of the light incident surface of the member is the thickness direction if the member is a light diffusion sheet, a prism sheet, a liquid crystal cell, a polarizing sheet, or a front panel in the case of a direct type. In the case of the light type, if the member is a light guide plate, the direction is from the edge where the light source is installed to the facing edge, and if the member is a light diffusion sheet, a prism sheet, a liquid crystal cell, a polarizing sheet or a front panel, the thickness is increased. Direction.

Further, the average transmittance (a) of light having a wavelength of 200 to 400 nm relative to the average transmittance (b) of light having a wavelength of 400 to 800 nm in the normal direction of the light incident surface of the member of the present invention. The ratio (a / b) is 0.3 or less, preferably 0.25 or less. When the ratio (a / b) exceeds 0.3, when the output of the cold-cathode tube is increased to brighten the liquid crystal display screen, peripheral members and articles may be affected by discoloration and the like as described above. .

The member having the light transmission characteristics as described above includes
For example, a substance having an absorption maximum in the range of 200 to 400 nm (hereinafter, sometimes referred to as an ultraviolet absorbent) is contained in a substrate, a film containing an ultraviolet absorbent is attached to the substrate, and an ultraviolet absorbent is deposited. It can be produced by using an ultraviolet absorber as one of the materials, for example, by adding it to a substrate by coating or coating. Above all, it is preferable to include an ultraviolet absorber in the base material.

When a resin is used as the base material, examples of the ultraviolet absorber include benzotriazoles, cyanoacrylates, hindered amines, benzophenones, salicylates, and the like. More than one species can be used. Among them,
Benzotriazoles and cyanoacrylates are preferred, and when two or more UV absorbers are used, they are preferably used in an amount of 50% by weight or more of the entire UV absorber.

As the benzotriazoles, for example,
2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-butylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-butylphenyl) Benzotriazole, 2- (2-hydroxy-3-tert-butyl-5-
Methylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3-
tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-4-n-octyloxyphenyl) benzotriazole, 2- (2-
Compounds having a benzotriazole skeleton such as hydroxy-3,5-di-isoamylphenyl) benzotriazole and 2- (2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl) -benzotriazole are exemplified. . Further, a compound in which a functional group such as a vinyl group, a (meth) acryloyl group, or a (meth) acryloyloxy group is introduced into these compounds may be used.

Examples of the cyanoacrylates include ethyl 2-cyano-3,3-diphenylacrylate, 2-ethylhexyl 2-cyano-3,3-diphenylacrylate, and 2-cyano-3-methyl-3. And butyl (4-methoxyphenyl) acrylate.

The hindered amines include, for example, dimethyl succinate / 1- (2-hydroxyethyl) -4-
Hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly ((6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-
Diyl) ((2,2,6,6-tetramethyl-4-piperidyl) imino) hexamethylene ((2,2,6,6-
Tetramethyl-4-piperidyl) imino)), 2-
Bis (2,3-di-tert-butyl-4-hydroxybenzyl) -2-n-butylmalonate
6-pentamethyl-4-piperidyl), 2- (3,5-
Di-tert-butyl-4-hydroxybenzyl) -2-n
Bis (1,2,2,6,6-pentamethyl-4-piperidyl) -butylmalonate, N, N'-bis (3-aminopropyl) ethylenediamine / 2,4-bis (N-butyl-N- ( 1,2,2,6,6-pentamethyl-4-piperidyl) amino) -6-chloro-1,3,5-triazine condensate, bis (2,2,6,6-tetramethyl-4
-Piperidyl) sebacate, bis (2,2, succinate)
6,6-tetramethyl-4-piperidyl) and the like.

Examples of benzophenones include, for example, 2,
4-dihydroxybenzophenone, 2-hydroxy-4
-Methoxybenzophenone, 2,2'-dihydroxy-
4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sulfobenzophenone, 2-hydroxy-4-methoxy-2'- Carboxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone trihydrate, 2-hydroxy-4-n-octyloxybenzophenone, 2
-Hydroxy-4-octadecyloxybenzophenone,
Compounds having a benzophenone skeleton such as 2,2 ', 4,4'-tetrahydroxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, and 2-hydroxy-4- (2-hydroxy-3-methacryloyloxypropoxy) benzophenone are exemplified. Can be

Examples of salicylates include, for example,
Methyl salicylate, phenyl salicylate, p-octylphenyl salicylate, p-tert-butylphenyl salicylate and the like can be mentioned.

Examples of commercially available products include “Sumisorb” (trade name of Sumitomo Chemical Co., Ltd.), “Tinuvin” and “Cimasorb” (trade names of Nippon Ciba Geigy Co., Ltd.), and “Trade name” of Cipro Kasei Co., Ltd. SEESORB ", trade name" Adeka Stub "of Asahi Denka Kogyo Co., Ltd., trade name" Ubinar "of BASF, and trade name" Sanol "of Sankyo Co., Ltd.

When glass is used as the substrate, compounds containing divalent and / or trivalent iron ions, compounds containing trivalent and / or tetravalent cerium ions, and trivalent and / or Examples include compounds containing tetravalent titanium ions, and two or more of them can be used as necessary.

When the member of the present invention is a light diffusion sheet,
Usually, light diffusing properties are imparted by dispersing a light diffusing agent in a substrate. As the light diffusing agent, inorganic or organic transparent particles having a different refractive index from the substrate can be used. The difference in the refractive index between the substrate and the light diffusing agent preferably has an absolute value in the range of 0.02 to 0.13. Further, the particle size of the light diffusing agent is preferably in the range of 1 to 50 μm on a weight average. The amount of the light diffusing agent is preferably in the range of 0.1 to 10 parts by weight based on 100 parts by weight of the substrate.

When a resin is used as the substrate, examples of the light diffusing agent include calcium carbonate, barium sulfate, titanium oxide, aluminum hydroxide, silica, glass, talc, and the like.
Examples include inorganic particles such as mica, white carbon, magnesium oxide, and zinc oxide; and resin particles such as crosslinked or high molecular weight styrene resin particles, crosslinked or high molecular weight acrylic resin particles, and crosslinked siloxane resin particles. These particles may have been subjected to a surface treatment.

When glass is used as the substrate, examples of the light diffusing agent include fluorite, creolite, sodium silicate fluoride, barium sulfate, phosphoric acid, and dibasic calcium phosphate.

The member of the present invention has an average transmittance (c) of light having a wavelength of 800 to 900 nm in the normal direction of the light incident surface.
Is preferably at most 30%, more preferably at most 20%. By setting the average transmittance (c) of light having a wavelength of 800 to 900 nm to 30% or less, it is possible to prevent malfunction of a remote control device located around the liquid crystal display device. The lower limit of the average transmittance (c) of light having a wavelength of 800 to 900 nm is not particularly limited, but is usually 0.01 from the viewpoint of suppressing the color tone of transmitted light from becoming blue.
% Or more.

The average transmittance (c) of the light having a wavelength of 800 to 900 nm relative to the average transmittance (b) of the light having a wavelength of 400 to 800 nm in the normal direction of the light incident surface of the member of the present invention. The ratio (c / b) is preferably 0.6 or less, more preferably 0.4 or less. This ratio (c
By setting / b) to 0.6 or less, even when the output of the cold-cathode tube is increased to brighten the liquid crystal display screen, malfunction of the remote control device located around the liquid crystal display device is prevented as described above. be able to.

A member having such an infrared light transmission characteristic is prepared by, for example, adding a substance having an absorption maximum in the range of 800 to 900 nm (hereinafter sometimes referred to as an infrared absorbent) to a base material. It can be produced by using an infrared absorbing agent as one of the materials, such as attaching a film containing the agent to the substrate, or adding an infrared absorbing agent to the substrate by vapor deposition or coating. Above all, it is preferable to include an infrared absorber in the base material.

When a resin is used as the substrate, examples of the infrared absorber include JP-A-4-174402,
Aminium-based compounds as described in JP-A-4-160037; JP-A-61-115958, JP-A-61-291651, and JP-A-62-1.
Anthraquinone compounds as described in JP-A-32963, JP-A-1-172458 and the like; JP-A-2-138382, JP-A-3-62878, JP-A-5-163440, JP-A-6-163440 −214
Phthalocyanine-based compounds and naphthalocyanine-based compounds described in JP-A-113, etc .;
No. 77903, JP-A-61-57674, JP-A-62-158779, JP-A-63-1393
No. 03, JP-A-1-114801, Japanese Patent Publication No.
Dithiol complex-based compounds as described in -45547 and the like; polymethine-based compounds, pyrylium-based compounds, thiopyrylium-based compounds, squararylium-based compounds, croconium-based compounds, azurenium-based compounds,
Examples thereof include a tetradehydrocholine-based compound, a triphenylmethane-based compound, and a diimmonium-based compound. If necessary, two or more of them can be used.

Examples of commercially available products include IR-750, IRG-002, and IRG-0 manufactured by Nippon Kayaku Co., Ltd.
03, IRG-022, IRG-023, IRG-82
0, CY-2, CY-4, CY-9, CY-20; PA-001, PA-1005, PA- manufactured by Mitsui Chemicals, Inc.
1006, SIR-114, SIR-128, SIR-
130, SIR-159; IRF-700, IRF-770, IRF-800, IRF-700 manufactured by Fuji Photo Film Co., Ltd.
RF-905, IRF-1170; EEX Color 802K and EEX Color 803 manufactured by Nippon Shokubai Co., Ltd.
K, EEX Color 812K, EEX Color 90
5B and the like.

When glass is used as the base material, examples of the infrared absorber include copper oxide and arsenic compounds, and two or more of them can be used as necessary.

In the member of the present invention, if necessary, for example, if the substrate is a resin, methyl methacrylate-based crosslinked particles,
Matting agents such as glass particles and talc; antistatic agents such as sodium alkyl sulfonate, sodium alkyl sulfate, monoglyceride stearate, polyetheresteramide; antioxidants such as hindered phenol; phosphoric acid esters One or more additives such as a flame retardant, a lubricant such as palmitic acid and stearyl alcohol may be contained.

As a method for producing the member of the present invention, a known method can be employed. When the base material is a resin, for example, the resin, an ultraviolet absorber and other components are melt-kneaded as necessary, and at a temperature suitable for the resin used, by an extrusion molding method, an injection molding method, a press molding method, or the like. Molding method: Dissolving or dispersing an ultraviolet absorber and other components as necessary in a monomer component or a partially polymer syrup thereof as a raw material of a resin, and performing bulk polymerization, for example, polymerization in a cell or a mold. A method for forming a predetermined shape; a solution in which a resin, an ultraviolet absorber and other components are dissolved in an appropriate solvent as necessary, is applied to the surface of the resin sheet, and the solvent is volatilized, and the ultraviolet absorber and the A method of forming a resin layer containing other components according to the requirements; a resin sheet is prepared by using an ultraviolet absorbent obtained according to the above method and a sheet containing other components as necessary, using an adhesive or the like. Paste or pre The method or the like to melt laminating the like.

When the substrate is glass, for example, glass,
A method in which an ultraviolet absorber and other components are heated and melted in a noble metal such as platinum or an alumina or silica crucible, poured into molten tin, and cooled and flattened; A method in which a solution in which an ultraviolet absorber and other components are dissolved in an appropriate solvent as necessary is applied, and the solvent is volatilized to form a resin layer containing the ultraviolet absorber and other components as necessary; A method of bonding a sheet containing an ultraviolet absorber and other components as necessary to the glass sheet according to the method in the case where the base material is a resin, using an adhesive or the like, and the like. .

The thickness of the member of the present invention is usually 0.1 to 20.
mm, specifically 0.1 to 5 mm for a light diffusing sheet, 2 to 20 mm for a light guide plate, 0.1 to 3 mm for a prism sheet, 0.1 to 3 mm for a liquid crystal cell.
2 mm, usually 0.1 to 2 mm for a polarizing sheet, and usually 0.5 to 10 mm for a front panel.

As the members of the present invention, among the members for a liquid crystal display device, a light guide plate, a light diffusion sheet, a prism sheet,
A liquid crystal cell, a polarizing sheet or a front panel is preferable, a light guide plate, a light diffusion sheet and a front panel are more preferable, and a light guide plate is particularly preferable.

The member of the present invention can be suitably used for a liquid crystal display device having a screen having a diagonal inch of 14 inches or more, and particularly preferably for a liquid crystal display device having a screen diagonal of 20 inches or more.

[0042]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited to these examples. In addition, an ultraviolet absorber,
The following infrared absorbing agents were used. (A): UV absorber [Sumitomo Chemical Co., Ltd., trade name: Sumisorb 200 (benzotriazole type)] (B-1): Infrared absorber [Nippon Shokubai Co., Ltd., trade name: EEX Color 812K (phthalocyanine-based)] (B-2): Infrared absorbent [manufactured by Nippon Shokubai Co., Ltd., trade name: EEX Color 901K (phthalocyanine-based)] (B-3): Infrared absorbent [Nippon Shokubai Co., Ltd. Product name: EEX Color 905B (phthalocyanine)

The configuration of the extruder used for producing the sheet is as follows.・ Extruder: Screw diameter 40 mm, uniaxial, with vent (manufactured by Tanabe Plastics Co., Ltd.) ・ Die: T die, lip width 250 mm, lip interval 6 m
m ・ Roll: 3 polishing rolls, vertical type

As for the physical properties relating to the light transmittance, a spectrophotometer (U4000, manufactured by Hitachi, Ltd.)
Was used to measure the light transmittance in the range of 200 to 900 nm in steps of 5 nm, and the following values were calculated. (A): average transmittance of light having a wavelength of 200 to 400 nm (b): average transmittance of light having a wavelength of 400 to 800 nm (c): average transmittance of light having a wavelength of 800 to 900 nm (a / b): wavelength 400 Ratio of average transmittance (a) of light having a wavelength of 200 to 400 nm to average transmittance (b) of light having a wavelength of 800 to 800 nm (c / b): wavelength 800 to average transmittance (b) of light having a wavelength of 400 to 800 nm Ratio of average transmittance (c) of 900 nm light

Examples 1-3, Comparative Example 1 100 parts by weight of methyl methacrylate resin (copolymer of methyl methacrylate / methyl acrylate = 96/4 (weight ratio), refractive index 1.49) and Table 1 After mixing the types and amounts (parts by weight) of the ultraviolet absorber and the infrared absorber shown in (1) using a Henschel mixer, the mixture was melt-kneaded using an extruder, and extruded at a resin temperature of 265 ° C. at a thickness of 4 mm and a width of 4 mm. 22c
m sheets were produced. The obtained sheet is 5 cm x 30
After being cut into a cm and polished at the end face, the transmittance in an optical path of 30 cm was measured. Table 1 shows the physical property values.

[0046]

[Table 1]

Further, the obtained sheet was processed into a 20-inch type (two sheets cut into 30 cm × 20 cm were arranged side by side to make 30 cm × 40 cm), a cold cathode tube was set on the side of 40 cm, and a side of the side of 30 cm was set. A white reflective adhesive tape was applied. When the power was turned on for 2000 hours while the power of the cold cathode fluorescent lamp was turned on, only in Comparative Example 1, the white reflective adhesive tape was deteriorated and colored.

Examples 4 to 7 100 parts by weight of methyl methacrylate resin (refractive index: 1.49), 11 parts by weight of crosslinked acrylic particles (Sumitomo Chemical Industries, Ltd., trade name: SUMIPEX XC1A) as a matting agent And sodium cetylsulfonate as an antistatic agent.
5 parts by weight, calcium carbonate (refractive index 1.
61, a particle size of 3 μm), 4.5 parts by weight, and the kind and amount (parts by weight) of an ultraviolet absorber and an infrared absorber shown in Table 2 were mixed using a Henschel mixer, and then, using an extruder,
Melt kneaded, extruded resin temperature 265 ℃, thickness 2mm,
A sheet having a width of 21 cm was prepared. The light transmittance in the thickness direction of the obtained sheet was measured. Table 2 shows the physical property values.

[0049]

[Table 2]

The obtained sheet was processed into a 20-inch type in the same manner as in Example 1, and was placed at a position 1 cm away from the front surface of the nine cold cathode tubes arranged side by side. A 1 cm × 1 cm white reflective pressure-sensitive adhesive tape was attached to the surface facing the surface. When the cold-cathode tube was left lit for 2000 hours, no deterioration or coloring of the white reflective pressure-sensitive adhesive tape was observed in any of the examples.

Further, a remote-control lighting device is installed at a position 1 m away from the front of the sheet, and the power supply of the cold cathode fluorescent lamp is turned off.
Switching between N and OFF was repeated to check if the lighting equipment malfunctioned. In any case,
No malfunction was observed.

[0052]

By using the member for a liquid crystal display device of the present invention, deterioration of peripheral members and articles can be suppressed. Further, by controlling the transmittance of light on the long wavelength side, it is possible to suppress a malfunction of a remote controller of another device placed around the liquid crystal display device. The member for a liquid crystal display device of the present invention is particularly useful when a high brightness type light source is used.

[Brief description of the drawings]

FIG. 1 is a view showing an example of arrangement of members of the present invention (direct type).

FIG. 2 is a diagram showing an example of arrangement of members of the present invention (edge light type).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Reflection sheet 2 ... Cold cathode tube 3 ... Light diffusion sheet 4 ... Prism sheet 5 ... Polarizing sheet 6 ... Liquid crystal cell 7 ... Front panel 8 ... Light guide plate

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) G02F 1/1335 G02F 1/1335 F-term (Reference) 2H042 AA06 AA11 AA26 BA02 BA15 BA20 CA12 CA17 2H048 CA04 CA05 CA06 CA12 CA13 CA19 CA24 CA27 2H049 BA02 BB02 BB63 BC22 2H091 FA08Z FA21Z FA23Z FA32Z FA42Z FB02 FD06 FD22 KA10 LA03

Claims (4)

[Claims] 1. A wavelength of 200 to 4 in a direction normal to a light incident surface.
An average transmittance (a) of light of 00 nm is 20% or less;
And the average transmittance (b) of light having a wavelength of 400 to 800 nm.
Wherein the ratio (a / b) of the average transmittance (a) of light having a wavelength of 200 to 400 nm to the liquid crystal display device is 0.3 or less. 2. A wavelength of 800 to 9 in a direction normal to a light incident surface.
An average transmittance (c) of light of 00 nm is 30% or less;
And the average transmittance (b) of light having a wavelength of 400 to 800 nm.
2. The member for a liquid crystal display device according to claim 1, wherein a ratio (c / b) of an average transmittance (c) of light having a wavelength of 800 to 900 nm is 0.6 or less. 3. A light guide plate, a light diffusion sheet, a prism sheet,
The liquid crystal display device member according to claim 1, which is a liquid crystal cell, a polarizing sheet, or a front panel. 4. The screen of the liquid crystal display device has a diagonal inch of 14.
The member for a liquid crystal display device according to any one of claims 1 to 3, which is not less than inches.