JP2002189423A - Filter for direct sticking to plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter which is directly stuck to the front face of a plasma display panel. SOLUTION: The filter for direct sticking to a plasma display panel is obtained by sticking a surface film (A) having 107-1010 Ω/sq. surface resistance, including an antistatic layer and having antireflection function to a near IR cutting film (B) having <=10% average transmittance to near IR of 800-1,000 nm with a UV absorbing transparent adhesive (sticky) layer (C) and further sticking a transparent pressure sensitive adhesive (sticky) layer (D) for sticking to the surface of a plasma display to the near IR cutting film (B). The total thickness of the resulting laminate (A)-(D) is 0.2-0.5 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a filter directly attached to the front of a plasma display panel.

[0002]

2. Description of the Related Art Conventionally, display has been CR
T (Cathode Ray Tube) was the mainstream, but recently FPD (Flat Panel Di)
spray) has been developed and commercialized. However,
LCD (Liquid Crystal Di), which is expanding its market by utilizing functions such as thinness, light weight, and low power consumption
Spray is widely used, but PDP (Plasma Display) which is thin and is applied to a large screen.
y Panel) is attracting attention.

[0003] Since a PDP utilizes a light emission phenomenon accompanying gas discharge, a large current flows and a magnetic field is generated.
For this reason, there is a concern that the electromagnetic waves generated from the PDP may affect the human body and other electronic devices. For this reason,
Attachment of an electromagnetic wave shielding filter to a PDP has been studied.

The basic structure of a DC type PDP is to selectively discharge and emit phosphors in a large number of display cells separated between two glass plates, and a partition is provided between a front glass and a rear glass. A display cell, an auxiliary cell, and the like are arranged, and a red phosphor, a green phosphor, and a blue phosphor are provided in a film on the inner wall of each display cell. These phosphors emit light when discharged by the voltage applied to the cathode, display anode, and auxiliary anode. For this reason, it is inevitable that electromagnetic waves of several kHz to several GHz are generated from the front surface of the PDP due to voltage application, discharge, light emission, and the like, and it is necessary to shield the electromagnetic waves.

[0005]

For this reason, conventionally, a transparent filter having an electromagnetic wave shielding function is arranged on the front surface of a PDP in order to shield electromagnetic waves from the PDP. That is, the filter used to prevent the leakage of the electromagnetic wave has a structure in which a conductive mesh material such as a wire mesh is interposed between transparent substrates such as an acrylic plate to be integrated, and is not closely attached to the PDP light emitting panel. Independently placed. For this reason, it is inevitable that the transmittance decreases and the reflectance increases. In addition, a substrate is required for self-sustaining, and in some cases, antireflection treatment is required on the back surface of the base material, which increases costs. Furthermore, since it is necessary to provide a metal electrode on a conductive material and electrically connect to a metal part of the housing or the like to ground, the manufacturing cost is high and the design is limited. there were.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the gist of the invention is that the sheet resistance is in the range of 10 ⁷ to 10 ¹⁰ Ω / □. A surface film (A) having an antireflection function containing
A near-infrared cut film (B) having an average transmittance of 10% or less of near-infrared light of up to 1000 nm is bonded to the near-infrared cut film (B) by an ultraviolet-absorbing transparent adhesive layer (C). The transparent pressure-sensitive adhesive (D) for bonding to the plasma display surface is bonded, and the total thickness of the laminates (A) to (D) is 0.2.
The filter according to the present invention is a filter for directly attaching a plasma display panel, characterized by having a thickness of 0.5 mm.

[0007] Preferably, (B), (C),
(D) at least one layer has a wavelength of 610;
the ratio of the absorbance μ ₅₉₀ at a wavelength of 590 nm to the absorbance μ _{610 at} nm is 2 or more;
Any one of (A), (B), (C), and (D)
The layer, or another additional layer, may be provided with colored frame printing. Of course, the laminate should be cut into a shape conforming to the bonded portion of the flat display.

The antireflection-treated surface film (A) used in the present invention may be a transparent film such as a polyethylene terephthalate (PET) film or a triacetyl cellulose (TAC) film, or a cured acrylic or silicon resin. The film is applied to a thickness of 2 to 15 microns and a hard coat layer is provided. Then, fine particles such as silica, indium oxide, and titanium oxide may be mixed in the hard coat layer. On top of that, two or three layers of thin films made of materials having different refractive indices are laminated, and reflected light in the visible region is reduced by interference (anti-reflection function). For this, a technique known as an antireflection coating can be used. Conductive fine particles (for example, indium oxide, tin oxide, ITO, A
TO, zinc oxide, etc.) by mixing, a surface resistance of 10 ⁷ -
Set to 10 ¹⁰ Ω / □. The purpose is to prevent surface electrification. If the sheet resistance is higher than this range, the antistatic effect is not sufficient, and if the sheet resistance is lower than this range, the conductive layer on the surface tends to be charged up, so that the ground must be taken. In addition, the measurement of the sheet resistance was measured by a high-resistor sheet resistance measuring device: a two-terminal type resistance measuring instrument manufactured by Dia Instruments.

A known film can be used as the near infrared cut film (B). In particular, it is preferable to coat a PET film or the like with one or more dyes such as a metal dithiolene dye, a ferrocyanine dye, a cyanine dye, and a diimonium dye mixed in a transparent resin. An interference filter in which a silver-based thin film and a metal oxide thin film well known as a heat ray reflective film are alternately laminated may be used as the near-infrared cut film (B).

The UV-absorbing transparent adhesive (adhesive) agent layer is not particularly limited as long as it is known as a transparent adhesive (adhesive) agent. For example, an acrylic adhesive such as butyl acrylate, ethylene-vinyl acetate, etc. It is preferable to use a transparent adhesive sheet based on a copolymer or the like mixed with an appropriate amount of a known ultraviolet absorbing dye. As the ultraviolet cut property, the transmittance at 380 nm is preferably 30% or less,
5% or less is more preferable. If it is higher than this, the shielding ratio of ultraviolet rays is not sufficient, and the near infrared cut film and other materials may be deteriorated by external ultraviolet rays during use.

As the transparent pressure-sensitive adhesive (adhesive) (D), known ones are used, and are based on acrylic adhesives such as butyl acrylate, rubber adhesives, and thermoplastic elastomer resins such as SEBS and SBS. TPE-based pressure-sensitive adhesives are preferred.

According to the present invention, there is provided a filter which can be directly attached to the surface of a plasma display panel. The filter has an antireflection function, an antistatic function, a near-infrared cut function, and an ultraviolet absorption function. The filter is a combined filter, and is directly attached to the surface glass of the light emitting panel with a pressure-sensitive adhesive (or adhesive) on the back surface.

Recently, control circuits and luminous efficiency of PDPs have been improved, and the amount of electromagnetic waves radiated from PDP light-emitting panels has been reduced. Therefore, the conductive material and the electrode as described above are becoming unnecessary, but the conductive material as described above may be used without any problem, and an electrode for grounding may be provided as necessary. Thereby, it is natural that leakage electromagnetic waves can be extremely reduced.

By setting the total thickness of the laminated body to 0.2 or more, stability such as impact or breakage is secured without providing a self-standing filter.
The handling of the laminate and the workability of the lamination are improved by the following.

Further, any one of these layers may have
By mixing a dye having a maximum absorption in the range of 595 nm by a method such as coating or kneading, a wavelength of 610 nm is obtained.
The ratio of the absorbance μ _{590 at} the wavelength 590 to the absorbance μ _{610 at} 2 can be 2 or more. This is 2
With the above, the color tone of the plasma display becomes more beautiful. That is, among the PDP emission colors, this peak near 590 nm is close to vermilion and causes deterioration of color reproducibility, which causes poor color purity and color reproducibility. Therefore, by using such a dye, the peaks near the wavelengths of 590 and 600 nm were canceled out, whereby the redness of the RED spectrum could be improved. In addition, as an example of such a dye,
Cyanine dyes, azulenium dyes, squarium dyes, diphenylmethane dyes, triphenylmethane dyes, oxazine dyes and the like can be mentioned.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As a surface film (A), an anti-reflection treatment is applied, and a film (Realck) (thickness: 0.1 mm) made of NOF having a surface resistance of 10 ⁹ Ω / □ and a near infrared cut film ( B) as a film made by Toyobo (with a thickness of 0.
1 mm 2) and bonded together as an adhesive (adhesive) agent layer (C) using an ultraviolet-cut adhesive film (EVASAFE) (0.15 mm thick) manufactured by Bridgestone. Then, an acrylic pressure-sensitive adhesive manufactured by Soken Chemical Co., Ltd. was applied to the near-infrared cut film (B) surface and the overall thickness was 0.4
mm was obtained. The acrylic pressure-sensitive adhesive was added with 0.5% by weight of a cyanine dye having an absorption maximum wavelength of 590 nm.

[0017]

The laminate obtained here was bonded to the glass surface of a plasma display panel. Then, an operation test was performed with an infrared remote controller in the vicinity of this, and it was found that there was no malfunction and the leaked near infrared rays were sufficiently shielded. Also, the screen was observed in a bright room, but the contrast was good and it was easy to see.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G02B 5/22 H05K 9/00 V 5G435 H01J 11/02 G02B 1/10 A H05K 9/00 Z F term (reference) 2H048 CA04 CA05 CA12 CA13 CA19 CA24 CA27 2K009 AA05 AA06 AA15 BB24 BB28 CC09 CC24 CC42 DD02 EE01 EE03 4F100 AR00B BA04 BA07 BA10A BA10D BA26 CB00C CB05D GB90 HB31A HB31B HB31C HB31D JD09C JD14A JD14B JD14C JD14D JG03A JG04A JL10A JL10B JL10C JL10D JL13D JN01B JN01C JN01D JN06A YY00A 5C040 GH10 MA08 5E321 AA04 AA05 AA23 BB25 BB44 BB57 CC16 GG05 GH01 5G435 AA01 BB06 CC12 FF14 GG11 GG12 GG16 KK02 KK05 KK07

Claims (4)

[Claims] 1. A filter directly attached to a plasma display panel, wherein the filter has a sheet resistance of 10 ⁷ to 10 ¹⁰ Ω /.
The surface film (A) having an anti-reflection function including the antistatic layer in the range of □ and the near-infrared cut film (B) having an average transmittance of 800-1000 nm of near-infrared light of 10% or less are ultraviolet rays. Absorbent transparent adhesive (adhesive) agent layer (C)
And a near-infrared cut film (B), and a transparent pressure-sensitive adhesive (adhesive) agent (D) for pasting to the plasma display surface, and laminating the above (A) to (D). Total body thickness 0.2 ~
A filter for directly attaching a plasma display panel, which is 0.5 mm. 2. One of (B), (C) and (D)
At least one layer has an absorbance μ at a wavelength of 610 nm.
₆₁₀ Absorbance μ at a wavelength of 590 nm ₅₉₀ of
The plasma display according to claim 1, wherein the ratio is 2 or more.
Filter for direct panel attachment. 3. The plasma display panel according to claim 1, wherein one of the layers (A), (B), (C), and (D) or another additional layer is printed with a colored frame. Filter for direct application. 4. The filter for directly attaching a plasma display panel according to claim 1, wherein the laminate is cut into a shape conforming to a portion where the flat display is attached.