JP2009031720A - Composite filter for display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite filter for a display, which is produced with excellent production efficiency by reducing the number of lamination processes, of which the number of stacked layers is few and the material cost is reduced, and in which near-infrared absorbing agent scarcely deteriorates even used for a long time under high temperature or high humidity conditions, while having at least respective functions of an electromagnetic shielding function to shield an electromagnetic wave mainly produced from a display such as a plasma display and a near-infrared absorbing function. <P>SOLUTION: The composite filter for the display is characterized in that it has a near-infrared absorbing layer containing a binder component and a transparent conductive layer stacked on one surface of a transparent glass substrate in this order, wherein the near-infrared absorbing layer contains composite tungsten oxide fine particles as the near-infrared absorbing agent. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a composite filter disposed on the front surface of a display (image display device) such as a PDP (plasma display panel). More specifically, the present invention relates to an electromagnetic wave shielding function for shielding electromagnetic waves generated from a display, and near infrared absorption. The present invention relates to a composite filter for display having a function.

  In recent years, with the advancement of functions and increase in the use of electrical and electronic equipment, electromagnetic noise interference (EMI) has increased, and electromagnetic waves are also generated in displays such as cathode ray tubes (referred to as CRT) and plasma display panels (referred to as PDP). appear. The plasma display panel is a combination of a glass having a data electrode, a fluorescent layer, and a glass having a transparent electrode, and generates a large amount of electromagnetic waves and near infrared rays when operated.

Usually, in order to shield electromagnetic waves, a laminate of an electromagnetic wave shielding sheet and a glass plate is provided as a front plate on the front surface of the plasma display panel. The shielding property of the electromagnetic wave generated from the front of the display is a standard applied to information processing devices used in home environments and residential environments specified by VCCI (Electromagnetic Interference Regulations for Information Processing Devices, etc.) at 30 MHz to 1 GHz in Japan ( It is necessary to achieve class B). In the present invention, the term “electromagnetic wave” refers to an electromagnetic wave having a frequency in the vicinity of the MHz to GHz band centered on the above range, and does not include infrared rays, visible rays, ultraviolet rays, X-rays, and the like ( For example, electromagnetic waves having a frequency in the infrared band are called infrared rays).
In addition, near infrared rays including a wavelength band of 800 to 1,100 nm generated from the front surface of the plasma display also cause malfunction of other devices such as a remote control device of the VTR, and thus need to be shielded. Furthermore, the function of improving the color reproducibility by blocking the light around the wavelength of 590 nm emitted from the plasma display (light emission of neon atoms enclosed in the PDP, hereinafter also referred to as neon light), adjusting the hue of the image, A function for suppressing unnecessary reflection of external light is required.

  In order to realize the above function, the electromagnetic wave shielding sheet and a plurality of optical filters such as a near-infrared absorption filter and an antireflection filter are laminated to prevent unnecessary electromagnetic waves and specific wavelength light generated from the image display device. It has been studied to use a plate-like composite filter that can shield and give various functions required for an image display device as a front plate of a plasma display panel (Patent Document 1).

JP 2002-311843 A JP 2005-181933 A JP 2006-154516 A

In Patent Document 1, visible light and an adhesive layer between the base material of the electromagnetic wave shielding sheet and the metal mesh, a flattening layer for flattening the unevenness of the metal mesh, or an adhesive layer with the glass substrate are used. An electromagnetic wave shielding sheet containing an absorbent that absorbs a specific wavelength in the near infrared is disclosed. When the organic near-infrared absorber is contained in the glass substrate, the metal mesh layer, or the portion in contact with the adhesive layer between the metal mesh layer and the base material of the electromagnetic wave shielding sheet, the near infrared ray There was a problem that the absorbent was likely to deteriorate. This is because alkali metal ions such as sodium ions derived from the glass substrate, metal atoms (or metal ions) such as copper derived from the conductive mesh, urethane bonds derived from the urethane adhesive layer, and organic dyes This is thought to be due to the reaction. Further, when an organic near-infrared absorber (pigment) is contained in a conventionally used acrylic pressure-sensitive adhesive layer that functions as a pressure-sensitive adhesive layer, the near-infrared absorber and these adjacent layers (particularly the pressure-sensitive adhesive). There is a problem that the change in the spectral characteristics of the optical filter due to the reaction with the polar functional group or residual monomer in the layer is promoted. It has been difficult to put into practical use a configuration in which an absorbent is contained and the layer is in contact with a metal mesh layer or a glass layer.
Patent Document 2 discloses an optical filter with an electromagnetic wave shield for PDP use that contains an absorbent that absorbs a specific wavelength in the near infrared. In such a case, in order to avoid contact between the glass substrate and the immonium-based near infrared absorber, if a resin substrate is inserted between the glass substrate and the immonium-based near infrared absorber, the glass substrate and the resin substrate Since an adhesive for adhering is required, there are problems that the number of processes increases and the material cost increases.

  On the other hand, Patent Document 3 discloses a near infrared absorption for PDP in which a coating film containing composite tungsten oxide fine particles having excellent weather resistance is used on the surface side of the plasma display (in the antireflection layer or on the front glass of the PDP main body). A filter is described. However, since the composite tungsten oxide fine particles are pigments, the layer in which the composite tungsten oxide fine particles are dispersed is colored. Therefore, when the near-infrared absorption filter as described in Patent Document 3 is disposed on the front surface of the display as it is, the layer in which the composite tungsten oxide fine particles are dispersed is disposed on the front surface of the display. When used as a layer placed on the viewer side, the front of the display appears to be colored with the color of the composite tungsten oxide particles when the display is turned off. Furthermore, since the composite tungsten oxide has a refractive index of 2.3 or higher and has a high refractive index, there is a problem that when it is located on the outermost surface layer, the surface reflection of extraneous light increases and the image contrast decreases, which is not preferred by the user. Patent Document 3 also describes that a layer in which composite tungsten oxide fine particles are dispersed is used as the high refractive index layer of the antireflection layer, but in this case as well, the antireflection layer serving as the outermost surface layer is used. Since the low refractive index layer is a thin film, when it is disposed on the front surface of the display, the front surface of the display appears to be colored with the color of the composite tungsten oxide fine particles. In addition, when composite tungsten oxide fine particles are contained in a layer provided as a relatively thin film such as an antireflection layer, a problem that the fine particle density in the layer increases and haze increases easily occurs. Furthermore, the addition of a material having a high refractive index (refractive index of 2.3 or more) such as a composite tungsten oxide to the antireflection layer whose refractive index should be strictly controlled to the design value can cause a change in the refractive index of the antireflection layer. This is not preferable. In particular, when the antireflection layer comprises only a low refractive index layer, it is difficult to express the low refractive index characteristics.

  The present invention has been made to solve the above-mentioned problems, and is excellent in production efficiency by reducing the number of lamination processes, with a small number of laminations, material costs can be reduced, coloring when the display is turned off is inconspicuous, and Located on the front of the display, the filter is less likely to cause color unevenness due to deterioration of the near-infrared absorber even when used for a long time, especially at high temperatures and high humidity. An object of the present invention is to provide a composite filter for display having at least each function of the absorption function.

  In the composite filter for display according to the present invention, a near-infrared absorbing layer containing a binder component and a transparent conductive layer are laminated in this order on one side of a transparent glass substrate. As an infrared absorber, general formula MxWyOz (where M element is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, One or more elements selected from V, Mo, Ta, Re, Be, Hf, Os, Bi, and I, W is tungsten, O is oxygen, 0.001 ≦ x / y ≦ 1.1, 2 .2 ≦ z / y ≦ 3.0) Characterized in that it contains the numeric oxide particles.

The composite filter for display according to the present invention is designed to combine various functions including an electromagnetic wave shielding function and a near-infrared absorption function with a small number of layers using one transparent glass substrate and both surfaces thereof. ing.
The composite tungsten oxide fine particles used as a near-infrared absorber in the present invention have high heat resistance, moisture resistance, and light resistance, and can be added to a glass even when added to a glass substrate or a layer in direct contact with a transparent conductive layer. There is no deterioration of the pigment due to metal ions (or metal ions) such as copper ions derived from sodium ions derived from the transparent conductive layer. In addition, since the composite tungsten oxide fine particles can absorb the entire near-infrared band having a wavelength of 800 to 1,100 nm generated from the front surface of the display only by the composite tungsten oxide fine particles, the iminium-based near infrared absorption that is more easily deteriorated. It is not necessary to use the agent in combination. Therefore, according to the composite filter for display of the present invention, color unevenness of the filter attributed to the deterioration of the near-infrared absorber occurs even when used for a long time, particularly for a long time under high temperature or high humidity. hard. In addition, in order to prevent deterioration of the near-infrared absorber, it causes deterioration of organic near-infrared absorbers such as a glass substrate such as a display surface, a transparent conductive layer, or an adhesive layer between optical filter substrates. There is no need to isolate the near-infrared absorbing layer from the layer or the like. Therefore, the composite filter for display according to the present invention is excellent in appearance due to no color unevenness of the filter or coloring due to the composite tungsten oxide fine particles, and has a function of shielding electromagnetic waves and a function of absorbing near infrared rays, and a lamination process. It has become possible to put to practical use a structure that can reduce the number of materials, has excellent production efficiency, and can reduce material costs with a small number of layers.
In addition, when the composite tungsten oxide fine particles are contained in a layer provided as a relatively thin film such as an antireflection layer, there is a problem that the fine particle density in the layer increases and haze increases. Thus, when it is made to contain in the layer containing a binder component, since a layer is thick compared with an antireflection layer, there also exists a merit that it can suppress that haze becomes high.

  In the composite filter for display according to the present invention, it is preferable that the transparent conductive layer is a conductive mesh layer from the viewpoint of achieving both electromagnetic shielding performance and light transmission performance.

  In the composite filter for display according to the present invention, it is preferable that a part of the peripheral edge of the conductive mesh layer is exposed. In the case of such an embodiment, a stripping process for grounding is not required, and a composite filter sticking process, planarization of the unevenness of the conductive mesh layer, and securing of a grounding region around the periphery of the conductive mesh layer are ensured. Since the steps can be performed simultaneously in one step, the number of steps can be further reduced and productivity is improved.

  In the composite filter for display according to the present invention, the near-infrared absorbing layer is laminated on the display side surface of the transparent glass substrate, and the antiglare function is provided on the viewer side surface of the transparent glass substrate. It is preferable from the point that appearance and optical characteristics can be improved by suppressing reflection of the background due to specular reflection of external light.

  In the composite filter for display according to the present invention, an electromagnetic wave shielding sheet comprising a transparent conductive layer on one surface side of the transparent resin substrate via the near-infrared absorbing layer on the viewer-side surface of the transparent glass substrate. The transparent conductive layer is laminated facing the transparent glass substrate, and a surface protective layer having an antiglare function and / or an antireflection function is formed on the surface of the electromagnetic shielding sheet on the transparent resin substrate side. It is preferable that the appearance and optical characteristics can be improved by suppressing the reflection of the background and the reflection of the surface due to the specular reflection of external light.

In the composite filter for display according to the present invention, the surface protective layer and / or the near-infrared absorbing layer preferably contains an ultraviolet absorber. In the case of such an embodiment, alteration or deterioration of the light absorber due to sunlight or illumination light can be prevented. Moreover, in the composite filter for display which concerns on this invention, it is preferable that the said near-infrared absorption layer further contains a neon light absorber and / or a color correction pigment | dye. With the above configuration, it is possible to reduce the step of attaching the functional filter composed of each functional layer and the base material, and thus the production efficiency is excellent. Further, since the number of stacked layers is reduced, the thickness is reduced and the material cost can be reduced.
Moreover, when it has a layer structure like this invention, there exists a merit that interface reflection can be suppressed by the number of layers reduction.

  In the composite filter for display according to the present invention, an electromagnetic wave shielding sheet comprising a transparent conductive layer on one surface side of the transparent resin substrate via the near-infrared absorbing layer on the viewer-side surface of the transparent glass substrate. Laminating the transparent conductive layer facing the transparent glass substrate, providing a grounding region not covered with a near-infrared absorbing layer on at least a part of the peripheral edge of the transparent conductive layer, A conductive member that contacts the transparent conductive layer is interposed between the transparent glass substrate and the transparent conductive layer, and the conductive member is displayed from the viewer side of the transparent glass substrate. By forming a conduction path that wraps around the panel side surface, the transparent conductive layer can be easily grounded from the display panel side surface of the transparent glass substrate through the conduction path.

  In the composite filter for display according to the present invention, the average dispersed particle size of the composite tungsten oxide fine particles is preferably 800 nm or less from the viewpoint of high transmittance in the visible region and low haze.

  In the composite filter for display according to the present invention, the composite tungsten oxide fine particles include one or more crystal structures of hexagonal crystal, tetragonal crystal, and cubic crystal from the viewpoint of improving the durability of optical characteristics. preferable.

  In the composite filter for display according to the present invention, in the general formula MxWyOz representing the composite tungsten oxide fine particles, the M element is Cs (cesium), and the composite tungsten oxide fine particles have a hexagonal crystal structure. From the viewpoint of improving the durability of the optical characteristics.

  In the composite filter for display according to the present invention, the surface of the composite tungsten oxide fine particles is coated with an oxide containing one or more elements selected from Si, Ti, Zr, and Al. It is preferable from the viewpoint of improving the durability of optical characteristics.

  The composite filter for display of the present invention has at least each function of an electromagnetic wave shielding function and a near-infrared absorbing function, while reducing the number of laminating steps and being excellent in production efficiency. There is an effect that interface reflection can be suppressed by reducing the number of layers. Furthermore, the composite filter for display of the present invention has an effect that the near-infrared absorbent is not easily deteriorated even when used for a long time, particularly for a long time under high temperature or high humidity.

  The present invention is described in detail below. In the present invention, the “transparent glass substrate” means a glass plate constituting a front plate (a plate-like filter externally attached separately from the PDP panel main body) and a glass plate on the observer side constituting the PDP panel main body. It means both. In addition, when the transparent glass substrate is a glass plate constituting the front plate, the “surface on the display panel side” means the side facing the display panel when the composite filter for display is arranged on the front side of the display panel. Of the face. The “observer side surface” means a surface opposite to the “display panel side surface”.

  In the composite filter for display according to the present invention, a near-infrared absorbing layer containing a binder component and a transparent conductive layer are laminated in this order on one side of a transparent glass substrate. As an infrared absorber, general formula MxWyOz (where M element is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, One or more elements selected from V, Mo, Ta, Re, Be, Hf, Os, Bi, and I, W is tungsten, O is oxygen, 0.001 ≦ x / y ≦ 1.1, 2 .2 ≦ z / y ≦ 3.0) Characterized in that it contains the numeric oxide particles.

<Layer structure of composite filter>
The layer structure of the composite filter for display according to the present invention will be described with reference to the drawings.
A sectional view of an example of a composite filter according to the present invention is conceptually shown in FIG. In the cross-sectional views of FIG. 1 and subsequent figures, for ease of explanation, the thickness direction (vertical direction in the figure) is greatly enlarged and exaggerated from the scale in the plane direction (horizontal direction in the figure). A composite filter 1 shown in FIG. 1 is a first embodiment of preferred embodiments of a composite filter according to the present invention, and is close to the transparent glass substrate 10 on the surface of the transparent glass substrate 10 on the PDP 60 side. From the side, the near-infrared absorbing layer 20 containing the binder component and the transparent conductive layer 50 are laminated in this order. Here, the near-infrared absorbing layer 20 is composed of a binder component and a general formula MxWyOz (where the M element is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, One or more elements selected from Br, Te, Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os, Bi, I, W is tungsten, O is oxygen, 0.001 ≦ x Composite tungsten oxide fine particles represented by /y≦1.1, 2.2 ≦ z / y ≦ 3.0).

FIG. 2 is a second embodiment of the preferred embodiment of the composite filter according to the present invention, in which a near-infrared absorbing layer 20 is formed on the surface of the transparent glass substrate 10 on the PDP 60 side. On the surface of the near-infrared absorbing layer 20, the surface on the conductive mesh 16 side of the electromagnetic shielding sheet provided with the conductive mesh layer 16 that is one form of the transparent conductive layer 50 on one surface of the transparent resin base material 12 is laminated. ing. Further, the conductive mesh layer 16 has a blackened layer 13 by blackening the surface opposite to the surface on the PDP 60 side.
The conductive mesh layer is difficult to exist as an independent layer because of its low mechanical strength. Therefore, the conductive mesh layer is usually formed by laminating a conductive layer on the surface of a transparent substrate (transparent resin substrate or transparent glass substrate) and forming the conductive layer into a mesh shape by etching. Next, in the transparent substrate on which the conductive mesh layer is laminated, the surface on the conductive mesh layer side or the surface on the transparent substrate side is laminated on the transparent glass substrate.

  FIG. 3 shows a third embodiment of the preferred embodiment of the composite filter according to the present invention. From the side near the transparent glass substrate 10 to the surface on the PDP 60 side of the transparent glass substrate 10, a near infrared ray is shown. The absorption layer 20 and the transparent conductive layer 50 are laminated in this order, and the antiglare layer 30 is formed on the surface of the transparent glass substrate 10 on the viewer 70 side.

  FIG. 4 shows a fourth embodiment of the preferred embodiment of the composite filter according to the present invention. From the side close to the transparent glass substrate 10 on the surface on the PDP 60 side of the transparent glass substrate 10, a near infrared ray is shown. The absorption layer 20 and the transparent conductive layer 50 are laminated in this order, and the antiglare layer 30 or the antireflection layer 40 is formed on the surface of the transparent glass substrate 10 on the viewer 70 side.

  FIG. 5 shows a fifth embodiment of the preferred embodiment of the composite filter according to the present invention. From the side near the transparent glass substrate 11 to the surface on the PDP 60 side of the transparent glass substrate 11, a near infrared ray is shown. The absorbing layer 20 and the transparent conductive layer 50 are laminated in this order, and the surface on the viewer 70 side of the transparent glass substrate 11 is roughened so as to have an antiglare function.

  FIG. 6 is a sixth embodiment among the preferred embodiments of the composite filter according to the present invention, in which an antiglare layer 30 is laminated on the surface on the observer side of the transparent resin substrate 12 side of the electromagnetic wave shielding sheet. A conductive mesh layer 16 that is one form of the transparent conductive layer 50 is formed on the surface of the electromagnetic wave shielding sheet on the PDP 60 side. A near-infrared absorbing layer 20 is formed on the surface of the conductive mesh layer 16 so as to flatten the unevenness of the conductive mesh layer 16, and a transparent glass substrate is formed on the surface of the near-infrared absorbing layer 20 on the PDP 60 side. The material 10 is affixed. The conductive mesh layer 16 in the electromagnetic wave shielding sheet has a blackened layer 13 formed on the surface on the transparent resin base material 12 side, and the conductive mesh layer 16 is a part of the grounding region in the peripheral portion. The part 15 is exposed. Further, a conductive member 17 is disposed on one side edge of the transparent glass substrate 10, and the conductive member 17 is connected to the grounding region 15 at the peripheral portion of the transparent conductive layer 16 as shown in FIG. 6. In contact with each other, a conductive path is formed along the surface on the PDP 60 side from the surface on the observer side of the transparent glass substrate 10. A gasket 18 is provided on the surface of the conductive member 17 on the PDP 60 side. Thereby, it is possible to easily ground the gasket 18 to the PDP main body. Further, the PDP main body can be grounded directly from the surface of the conductive member 17 on the PDP side. The conductive member 17 used in the present invention is not particularly limited as long as it is a substance having conductivity, but a metal is preferable in terms of good conductivity.

FIG. 7 shows a seventh embodiment of the preferred embodiments of the composite filter according to the present invention, in which an antiglare layer 30 is laminated on the surface on the observer side of the transparent resin substrate 12 side of the electromagnetic wave shielding sheet. The conductive mesh layer 16 that is one form of the transparent conductive layer 50 is formed on the surface of the electromagnetic wave shielding sheet on the PDP 60 side, and the conductive mesh layer 16 is formed on the surface of the transparent resin substrate 12 side. A blackening layer 13 is provided. Further, the near infrared absorption layer 20 is formed on the surface of the conductive mesh layer 16 so as to flatten the unevenness of the conductive mesh layer 16, and the near infrared absorption layer 20 becomes a sticking surface of the composite filter. The composite filter can be directly attached to the front surface (observer side) of the PDP 60.
In the composite filter for display according to the above embodiment, the layer in which the composite tungsten oxide fine particles are dispersed is disposed so as to be on the back side of the electromagnetic wave shielding sheet when viewed from the observer side when the PDP front surface is applied. The surface of the filter does not take on the color of the composite tungsten oxide fine particles, and when the PDP is placed on the front surface of the PDP and the PDP is turned off, the conventional problem that the front surface of the PDP appears to be colored and is not preferred by the user can be solved. . In addition, conventional problems such as image contrast reduction and external light reflection due to external light reflection on the surface due to the high refractive index of the composite tungsten oxide fine particles can also be solved.

According to the composite filter for display of the present invention, the near-infrared absorbing function, the antireflection function, the antiglare function, and / or the anti-glare function, in addition to the electromagnetic wave shielding function, using the glass plate constituting both front plates and both surfaces thereof. It can be designed to combine various functions such as an abrasion function. Therefore, the optical function developing part does not take a laminated structure having a plurality of transparent substrates (about 2 to 3 layers) in total, each having a transparent substrate. Therefore, the transparent base material of the optical filter which was conventionally contained two or more and the adhesive bond layer for bonding them together can be reduced. As a result, the composite filter for display of the present invention can reduce the material cost. Moreover, when it has a layer structure like this invention, there exists a merit that interface reflection can be suppressed by the number of layers reduction.
In addition, the transparent glass substrate used as a transparent substrate in the present invention is advantageous in that it has excellent heat resistance and scratch resistance and is inexpensive.

The composite tungsten oxide fine particles used as a near-infrared absorber in the present invention have high heat resistance, moisture resistance, and light resistance. In addition, it is contained in a layer that comes into contact with an adhesive layer between a glass substrate, a transparent conductive layer, or an optical filter substrate, such as a display front plate, which has been a cause of deterioration of conventional organic near-infrared absorbing dyes. However, it is difficult to cause characteristic deterioration due to reaction with these layers. In addition, since the composite tungsten oxide fine particles can absorb the entire near-infrared band having a wavelength of 800 to 1,100 nm generated from the front surface of the display only by the composite tungsten oxide fine particles, the iminium-based near infrared absorption that is more easily deteriorated. It is not necessary to use the agent in combination. Therefore, according to the composite filter for display of the present invention, color unevenness of the filter attributed to the deterioration of the near-infrared absorber occurs even when used for a long time, particularly for a long time under high temperature or high humidity. hard. In addition, there is no need to isolate the near-infrared absorbing layer from a glass substrate such as a display surface, a transparent conductive layer, or an adhesive layer between optical filter substrates in order to prevent deterioration of the near-infrared absorbing agent. . Therefore, it is excellent in appearance like the composite filter for display according to the present invention, and has each function of electromagnetic wave shielding function, near infrared ray absorption function and surface protection function, while reducing the number of laminating processes, and is excellent in production efficiency, and less laminating. The configuration that can reduce the material cost can be put into practical use.
In addition, when the composite tungsten oxide fine particles are contained in a layer provided as a relatively thin film such as an antireflection layer, there is a problem that the fine particle density in the layer increases and haze increases. Thus, when it contains in the layer containing a binder component, since a layer is thick compared with an antireflection layer, there also exists a merit that it can suppress that haze becomes high.
Hereinafter, the transparent glass substrate, the near-infrared absorbing layer, the transparent conductive layer, and the surface protective layer will be described in order for the composite filter used in the present invention.

1. Transparent glass substrate The transparent glass substrate is a support for the composite filter, and one surface may be roughened so as to have an antiglare function if necessary.
Transparent glass substrate is a support to reinforce the near-infrared absorbing layer with weak mechanical strength. If it has mechanical strength and light transmittance, it can be used with appropriate consideration of performance such as heat resistance. You may select according to. The higher the transparency of the transparent glass substrate, the better, but the light transmittance is preferably 70% or more, more preferably 80% or more in the visible light region of 380 to 780 nm. In addition, the light transmittance can be measured using a spectrophotometer (for example, UV-3100PC manufactured by Shimadzu Corporation) and a value measured in the air at room temperature.

  Examples of the glass used as the material for the transparent glass substrate include quartz glass, potash glass, borosilicate glass, and soda lime glass, but inexpensive soda lime glass (blue plate glass) is often used.

  The thickness of the transparent glass substrate may be basically selected according to the application and is not particularly limited, but is usually preferably about 1 mm to 5 mm. When the thickness is less than 1 mm, the mechanical strength is insufficient and warping, slackening, breakage, and the like occur, and when the thickness exceeds 5 mm, excessive performance increases the cost.

2. Near-infrared absorbing layer The near-infrared absorbing layer according to the present invention is a layer having a near-infrared absorbing function, and includes a binder component and a general formula MxWyOz (where M element is H, He, alkali metal, alkaline earth metal, rare earth) Element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, One or more elements selected from Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os, Bi, I , W is tungsten, O is oxygen, and contains composite tungsten oxide fine particles represented by 0.001 ≦ x / y ≦ 1.1, 2.2 ≦ z / y ≦ 3.0). It may contain other components such as an absorbent.
In addition to the adhesiveness that allows the transparent glass substrate and a transparent conductive layer to be described later to be bonded to the near-infrared absorbing layer, the transparent glass substrate can be reused after peeling (also known as reworkability). When the re-peelability is imparted, the near-infrared absorbing layer can be used as an adhesive layer. Therefore, when the near-infrared absorbing layer is used in the above-described form, a separate layer such as a pressure-sensitive adhesive layer is not necessary, and the production efficiency is further increased.

In the near-infrared absorbing layer according to the present invention, composite tungsten oxide fine particles are dispersed in the near-infrared absorbing layer to ensure the transparency required for the composite filter and the near-infrared absorbing function.
In addition to the composite tungsten oxide fine particles and the binder component, the near-infrared absorption layer may contain components that adjust optical functions such as an ultraviolet absorber, a neon light absorber, and a color correction dye.

(1) Composite tungsten oxide fine particles The general formula MxWyOz (wherein M element is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, One or more elements selected from Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os, Bi, I, W is tungsten, O is oxygen, 0.001 ≦ x / y ≦ 1 ., 1.2 ≦ z / y ≦ 3.0), the composite tungsten oxide fine particles function as a near infrared absorber in the present invention. Therefore, the near-infrared absorbing layer according to the present invention absorbs the near-infrared region generated when the plasma display panel emits light using xenon gas discharge, that is, the wavelength region of 800 nm to 1,100 nm. The near-infrared transmittance is preferably 10% or less, more preferably 5% or less.

  The composite tungsten oxide fine particles represented by the general formula MxWyOz is excellent in durability when it has a hexagonal, tetragonal or cubic crystal structure, and is therefore selected from the hexagonal, tetragonal and cubic crystals. Preferably it contains more than one crystal structure. For example, in the case of composite tungsten oxide fine particles having a hexagonal crystal structure, preferable M elements include Cs, Rb, Li, K, Ba, Ca, Sr, Fe, Tl, In, and Sn. Examples thereof include composite tungsten oxide fine particles containing one or more selected elements. Among them, the M element is preferably Cs (cesium) from the viewpoint of durability.

At this time, the addition amount x of M element to be added is preferably 0.001 or more and 1.0 or less, and more preferably around 0.33. This is because the value of x calculated theoretically from the hexagonal crystal structure is 0.33, and preferable optical characteristics can be obtained with the addition amount before and after this value. On the other hand, the abundance z of oxygen is preferably 2.2 or more and 3.0 or less. For example, Cs _0.33 WO ₃ , Rb _0.33 WO ₃ , K _0.33 WO ₃ , Ba _0.33 WO _{3 and the} like can be mentioned, provided that x and z fall within the above ranges. Useful near infrared absorption characteristics can be obtained.

Such composite tungsten oxide fine particles may be used alone or in combination.
In addition, coating the surface of the composite tungsten oxide fine particles with an oxide containing one or more elements of Si, Ti, Zr, and Al can further improve the weather resistance. preferable.

  The average dispersed particle size of the composite tungsten oxide fine particles is preferably 800 nm or less, more preferably 200 nm or less, particularly preferably 100 nm or less, from the viewpoint of transparency of the near-infrared absorbing layer. Here, the average dispersed particle size refers to a volume average particle size, and can be measured using a particle size distribution / particle size distribution measuring device (for example, Nanotrack particle size distribution measuring device manufactured by Nikkiso Co., Ltd.).

  Although content of composite tungsten oxide microparticles | fine-particles is not specifically limited, It is preferable that it is 1-25 weight% in a near-infrared absorption layer. If the content is more than 1% by weight, a sufficient near-infrared absorbing function can be exhibited, and if it is 25% by weight or less, a sufficient amount of visible light can be transmitted.

(2) Binder component In the near-infrared absorbing layer of the present invention, the binder component used together with the composite tungsten oxide fine particles uniformly disperses the composite tungsten oxide fine particles and forms a film on the near-infrared absorbing layer. Or, in order to impart adhesion to the substrate, it is blended as an essential component. In particular, when the near infrared absorbing layer has a function as an adhesive layer, an adhesive is used as a binder.
In addition, the binder component used in the near infrared absorption layer of the present invention needs to have transparency. The transparency of the binder component is not particularly limited as long as it is transparent to humans, but the haze according to JIS K7136 is preferably 5 or less, and particularly preferably 3 or less.
The binder component may be an organic material or an inorganic material as long as the composite tungsten oxide fine particles can be dispersed.
As the organic material, any of a non-polymerizable resin having no polymerization reactivity per se, an ionizing radiation curable resin, or a polymerization reactive resin such as a thermosetting resin may be used.
As the non-polymerizable resin, for example, (meth) acrylic resin, urethane resin, fluorine resin, silicon resin, polycarbonate resin, or polyester resin can be used. Since it is excellent in transparency, it is especially preferable. Here, the (meth) acrylic resin refers to an acrylic resin and / or a methacrylic resin. Hereinafter, similar abbreviations are used.
The acrylic resin is a polymer having a repeating unit derived from at least (meth) acrylic acid and a (meth) acrylic monomer of these derivatives.

Examples of the (meth) acrylic monomer include (meth) acrylic acid ester monomers such as (meth) acrylic acid alkyl ester monomers, and (meth) acrylic acid.
Examples of (meth) acrylic acid alkyl ester monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, sec-propyl (meth) acrylate, (meth) acrylic acid. n-butyl, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) acrylic acid Examples thereof include n-octyl, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, undecyl (meth) acrylate, and lauryl (meth) acrylate.

  Furthermore, in addition to the above, the acrylic resin used in the present invention may be copolymerized with a monomer having another functional group. Examples of monomers having other functional groups include monomers containing hydroxyl groups such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and allyl alcohol; (meth) acrylamide, N-methyl Monomers containing amide groups such as (meth) acrylamide and N-ethyl (meth) acrylamide; Monomers containing amide groups and methylol groups such as N-methylol (meth) acrylamide and dimethylol (meth) acrylamide; Monomers having functional groups such as monomers containing amino groups such as (meth) acrylate, dimethylaminoethyl (meth) acrylate and vinylpyridine; epoxy group-containing monomers such as allyl glycidyl ether and (meth) acrylic acid glycidyl ether It is below.

  The molecular weight of the acrylic resin is preferably 1,000 to 500,000, more preferably 10,000 to 100,000.

The ionizing radiation curable resin is represented by a group containing ethylenic double bonds such as vinyl group, (meth) acryloyl group, (meth) acryloyloxy group as a polymerizable functional group in the chemical skeleton of the non-polymerizable resin. Resin having a cationically polymerizable functional group introduced, such as a radically polymerizable unsaturated group or an epoxy group, or a polyfunctional monomer or oligomer having two or more polymerizable functional groups per molecule (also referred to as a prepolymer) Is used.
Examples of the radical polymerizable oligomer include various (meth) acrylate oligomers such as urethane (meth) acrylate, epoxy (meth) acrylate, and polyester (meth) acrylate, and unsaturated polyester oligomers.
Examples of the cationic polymerizable oligomer include novolac type epoxy resin oligomers, bisphenol type epoxy resin oligomers, and aromatic vinyl ether resin oligomers.
Among the polyfunctional monomers or oligomers, examples of the bifunctional monomer include di (meth) acrylates of alkylene glycol such as ethylene glycol, propylene glycol, and hexanediol; dialkylene glycol di (meth) acrylate such as polyethylene glycol and polypropylene glycol ( Mention may be made of (meth) acrylates.
Examples of the trifunctional monomer include tri (meth) acrylates of trihydric or higher polyhydric alcohols such as trimethylolpropane tri (meth) acrylate and pentaerythritol tri (meth) acrylate.
Examples of the tetrafunctional or higher polyfunctional monomer include pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate.
When ultraviolet rays or visible rays are used as the ionizing radiation, a photopolymerization initiator is added. Photopolymerization initiators include compounds such as benzophenone, thioxanthone, and benzoin in the case of radically polymerizable monomers or oligomers, and metallocenes, aromatics in the case of cationic polymerization monomers or oligomers. Group sulfonium-based and aromatic iodonium-based compounds are used. These photopolymerization initiators are added in an amount of about 0.1 to 5 parts by weight with respect to 100 parts by weight of the composition comprising the monomer and / or oligomer.
In addition, as the ionizing radiation, ultraviolet rays or electron beams are typical, but in addition, electromagnetic waves such as visible rays, X-rays and γ rays, or charged particle beams such as α rays can also be used.

  In addition, as the thermosetting resin, a thermosetting resin in which an epoxy-containing group such as a glycidyl group or the radically polymerizable unsaturated group is introduced into the chemical skeleton of the nonpolymerizable resin, or the nonpolymerizable resin is used. , An epoxy-containing group, or a composition obtained by mixing a polyfunctional epoxy resin having two or more radical polymerizable unsaturated groups per molecule is used. Alternatively, a so-called two-component curable urethane resin obtained by reacting a main agent composed of a polyol compound such as acrylic polyol or polyester polyol with a curing agent composed of an isocyanate compound such as hexamethylene diisocyanate or isophorone diisocyanate can also be used. .

  The total amount of the organic binder resin is preferably 40 to 99% by weight, more preferably 50 to 98% by weight, based on the solid content of the entire near-infrared absorbing layer.

On the other hand, the inorganic material is not limited as long as it has a high light transmittance in the visible light region. For example, a known organopolysiloxane or water glass (concentrated aqueous solution of sodium silicate) can be used.
Examples of the organopolysiloxane include: (1) organopolysiloxane that exhibits high strength by hydrolyzing and polycondensing chloro or alkoxysilane by sol-gel reaction or the like, and (2) a reaction having excellent water repellency and oil repellency. And organopolysiloxanes obtained by crosslinking a functional silicone.

If the above (1), the general formula _Y n _SiX 4-n 1, two or more hydrolyzable condensate of (n = 1 to 3) a silicon compound represented by the cohydrolysis condensate and mainly Become. In the above general formula, Y can include an alkyl group, a fluoroalkyl group, a vinyl group, an amino group, or an epoxy group, and X can include a halogen, a methoxyl group, an ethoxyl group, or an acetyl group.

  Specifically, methyltrichlorosilane, methyltribromosilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltri-t-butoxysilane; ethyltrichlorosilane, ethyltribromosilane, ethyltrimethoxysilane, Ethyltriethoxysilane, ethyltriisopropoxysilane, ethyltrit-butoxysilane; n-propyltrichlorosilane, n-propyltribromosilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltriisopropoxy Silane, n-propyltri-t-butoxysilane; n-hexyltrichlorosilane, n-hexyltribromosilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, n-hex Lutriisopropoxysilane, n-hexyltri-t-butoxysilane; n-decyltrichlorosilane, n-decyltribromosilane, n-decyltrimethoxysilane, n-decyltriethoxysilane, n-decyltriisopropoxysilane, n- Decyltri-t-butoxysilane; n-octadecyltrichlorosilane, n-octadecyltribromosilane, n-octadecyltrimethoxysilane, n-octadecyltriethoxysilane, n-octadecyltriisopropoxysilane, n-octadecyltrit-butoxysilane; Phenyltrichlorosilane, phenyltribromosilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriisopropoxysilane, phenyltri-t-butoxysilane; tetrachlorosilane Tetrabromosilane, tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, dimethoxydiethoxysilane; dimethyldichlorosilane, dimethyldibromosilane, dimethyldimethoxysilane, dimethyldiethoxysilane; diphenyldichlorosilane, diphenyldibromosilane, Diphenyldimethoxysilane, diphenyldiethoxysilane; phenylmethyldichlorosilane, phenylmethyldibromosilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane; trichlorohydrosilane, tribromohydrosilane, trimethoxyhydrosilane, triethoxyhydrosilane, triisopropoxy Hydrosilane, tri-t-butoxyhydrosilane; vinyltrichlorosilane, vinyltribromosilane, vinyltri Methoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, vinyltri-t-butoxysilane; trifluoropropyltrichlorosilane, trifluoropropyltribromosilane, trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, trifluoropropyl Triisopropoxysilane, trifluoropropyltri-t-butoxysilane; γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxy Propyltriethoxysilane, γ-glycidoxypropyltriisopropoxysilane, γ-glycidoxypropyltri-t-butoxysilane; γ-methacryloxypropylmethyldimethyl Xysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropyltriisopropoxysilane, γ-methacryloxypropyl Tri-t-butoxysilane; γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltriisopropoxysilane, γ- Aminopropyltri-t-butoxysilane; γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltrieth Xysilane, γ-mercaptopropyltriisopropoxysilane, γ-mercaptopropyltri-t-butoxysilane; β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane And partial hydrolysates thereof; and mixtures thereof can be used.

As the binder, polysiloxane containing a fluoroalkyl group can be preferably used. Specifically, one or more of the following hydrocondensation condensates and cohydrolysis condensates of fluoroalkylsilanes can be used. And those generally known as fluorine-based silane coupling agents can be used.
CF ₃ (CF ₂ ) ₃ CH ₂ CH ₂ Si (OCH ₃ ) ₃
CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OCH ₃ ) ₃
CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ Si (OCH ₃ ) ₃
CF ₃ (CF ₂ ) ₉ CH ₂ CH ₂ Si (OCH ₃ ) ₃
(CF ₃ ) ₂ CF (CF ₂ ) ₄ CH ₂ CH ₂ Si (OCH ₃ ) ₃
(CF ₃ ) ₂ CF (CF ₂ ) ₆ CH ₂ CH ₂ Si (OCH ₃ ) ₃
(CF ₃ ) ₂ CF (CF ₂ ) ₈ CH ₂ CH ₂ Si (OCH ₃ ) _{3
CF 3 (C 6 H 4)} C 2 H 4 Si (OCH 3) 3
CF ₃ (CF ₂ ) ₃ (C ₆ H ₄ ) C ₂ H ₄ Si (OCH ₃ ) ₃
CF ₃ (CF ₂ ) ₅ (C ₆ H ₄ ) C ₂ H ₄ Si (OCH ₃ ) ₃
CF ₃ (CF ₂ ) ₇ (C ₆ H ₄ ) C ₂ H ₄ Si (OCH ₃ ) ₃
CF ₃ (CF ₂ ) ₃ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂
CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂
CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂
CF ₃ (CF ₂ ) ₉ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂
(CF ₃ ) ₂ CF (CF ₂ ) ₄ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂
(CF ₃ ) ₂ CF (CF ₂ ) ₆ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂
(CF ₃ ) ₂ CF (CF ₂ ) ₈ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) _{2
CF 3 (C 6 H 4)} C 2 H 4 SiCH 3 (OCH 3) 2
_{CF 3 (CF 2) 3 (} C 6 H 4) C 2 H 4 SiCH 3 (OCH 3) 2
_{CF 3 (CF 2) 5 (} C 6 H 4) C 2 H 4 SiCH 3 (OCH 3) 2
_{CF 3 (CF 2) 7 (} C 6 H 4) C 2 H 4 SiCH 3 (OCH 3) 2
CF ₃ (CF ₂ ) ₃ CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃
CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃
CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃
CF ₃ (CF ₂ ) ₉ CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃
CF ₃ (CF ₂ ) ₇ SO ₂ N (C ₂ H ₅ ) C ₂ H ₄ CH ₂ Si (OCH ₃ ) ₃

By using a polysiloxane containing a fluoroalkyl group as described above as a binder, the water repellency of the non-light-irradiated part of the photocatalyst-containing layer is greatly improved, and the function of preventing the adhesion of the black matrix paint or the colored layer paint To express.
Examples of the reactive silicone (2) include compounds having a skeleton represented by the following chemical formula (1).

However, n is an integer of 2 or more. R ¹ and R ² are each a substituted or unsubstituted alkyl, alkenyl, aryl or cyanoalkyl group having 1 to 10 carbon atoms. In a molar ratio, 40% or less is vinyl, phenyl, or phenyl halide. In addition, it is preferable that R ¹ and R ² are methyl groups since the surface energy is the smallest, and it is preferable that the methyl groups are 60% or more in molar ratio. In addition, the chain end or side chain has at least one reactive group such as a hydroxyl group in the molecular chain.
In addition to the above organopolysiloxane, a stable organosilicon compound that does not undergo a crosslinking reaction, such as dimethylpolysiloxane, may be mixed in the binder.

The water glass is generally a high viscosity solution in which sodium silicate Na ₂ O.nSiO ₂ (n = 2 to 4) is dissolved in water. As a general method for producing water glass, silica sand and sodium carbonate or sodium hydroxide are mixed and melted at 1,100 ° C. or higher to obtain a glassy lump (called cullet), and this cullet is autoclaved. The method obtained by dissolving in water under pressure under pressure (5-7 kgf / cm ² × several hours) (dry method), mixing silica sand or silicate clay and sodium hydroxide, dissolving in an autoclave and filtering (Wet method).

  In the present invention, the adhesive used for the near-infrared absorbing layer uniformly disperses the composite tungsten oxide fine particles and the like, imparts film-forming properties, and can be bonded to the front surface of the display panel or other optical filters. As long as the function is given to the near-infrared absorbing layer, it is not particularly limited, and various conventionally known pressure-sensitive adhesives can be appropriately selected and used.

(3) Neon light absorber The neon light absorber is contained to absorb neon light emitted from the plasma display panel, that is, the emission spectrum of neon atoms. When a neon light absorber is included, at least orange light emission from the display can be suppressed, and a bright red color can be obtained. Since the emission spectrum band of neon light has a wavelength of 550 to 640 nm, it is preferable that the spectral transmittance when functioning as a neon light absorbing layer is designed to be 50% or less and further 25% or less at a wavelength of 550 nm. As the neon light absorber, a dye having an absorption maximum in a wavelength region of at least 550 to 640 nm can be used. Specific examples of the dye include cyanine, oxonol, methine, subphthalocyanine or porphyrin. Of these, porphyrins are preferred. Among them, a tetraazaporphyrin-based dye as disclosed in Japanese Patent No. 3834479 is particularly preferable from the viewpoint of good dispersibility in the near-infrared absorbing layer and good heat resistance, moisture resistance, and light resistance.
Although content of a neon light absorber is not specifically limited, It is preferable that it is 0.05 to 5 weight% in a near-infrared absorption layer. If the content is more than 0.05% by weight, a sufficient neon light absorbing function can be exhibited, and if it is 5% by weight or less, a sufficient amount of visible light can be transmitted.

(4) Color correction dyes Color correction dyes are included to adjust the color of the display filter to improve the color purity of the light emitted from the panel, the color reproduction range, and the display color when the power is turned off. The Since each display has a different color correction function requirement, the display is appropriately adjusted and used.
Examples of known dyes that can be used as color correction dyes include the dyes described in JP 2000-275432 A, JP 2001-188121 A, JP 2001-350013 A, JP 2002-131530 A, and the like. Can be suitably used. In addition, other dyes such as anthraquinone, naphthalene, azo, phthalocyanine, pyromethene, tetraazaporphyrin, squarylium, and cyanine that absorb visible light such as yellow light, red light, and blue light. Can be used.
The content of the color correction dye is appropriately adjusted according to the color to be corrected and is not particularly limited. Usually, it contains about 0.01 to 10 weight% in a near-infrared absorption layer.

(5) Other components The near-infrared absorbing layer in the present invention may contain a cross-linking agent such as an isocyanate compound, a tackifier, and the like, if desired.
In addition, the near-infrared absorbing layer may contain various dispersants, various surfactants, silane coupling agents, and the like as dispersants for improving the dispersibility of the composite tungsten oxide fine particles.
Moreover, as long as the effect of the present invention is not impaired, a near infrared absorber other than the composite tungsten oxide fine particles may be included. The near infrared absorber other than the composite tungsten oxide fine particles is appropriately selected from inorganic near infrared absorbers such as tungsten oxides other than those represented by the above general formula.

(6) Formation of near-infrared absorbing layer The near-infrared absorbing layer is a coating solution for the near-infrared absorbing layer containing at least the specific composite tungsten oxide fine particles and the binder component described above, for example, the first embodiment. (See FIG. 1), it can be formed by a wet film-forming method such as coating on the transparent conductive layer.
In order to improve the dispersion of the specific composite tungsten oxide fine particles, the near-infrared absorbing layer coating solution may contain a surfactant or a silane coupling agent as necessary. The composite tungsten oxide fine particle dispersion is prepared by appropriately dispersing in advance in advance, and then the fine particles are dispersed by mixing the dispersion, the binder component and, if necessary, a solvent and / or an adhesive. Is preferably uniform and good.

Further, on the conductive mesh layer surface described later, when providing a near infrared absorption layer so as to flatten the irregularities of the conductive mesh layer and expose a part of the peripheral edge of the conductive mesh layer, The near-infrared absorbing layer is intermittently applied or intermittently bonded. In order to expose a part of the peripheral edge of the conductive mesh layer, the near-infrared absorbing layer is not formed on the entire surface but is formed in a pattern.
The near-infrared absorbing layer may be coated or bonded so that the near-infrared absorbing layer surface is flattened while completely filling the uneven portion so that air does not enter the unevenness of the conductive mesh layer. From the viewpoint of improving the transparency of the composite filter. Further, as a part of the peripheral portion of the conductive mesh layer to be exposed, a portion used as a grounding region described later is sufficient. Especially, it is preferable that a near-infrared absorption layer is provided so that all the 4 edge parts of the said electroconductive mesh layer may be exposed.

3. Transparent conductive layer The transparent conductive layer is a layer having light transparency through which the display image of the PDP can be viewed through the transparent conductive layer, and having conductivity that can shield electromagnetic waves generated from the PDP. means. Moreover, since the transparent conductive layer has a low mechanical strength, it is difficult to exist as an independent layer. Usually, the transparent conductive layer is laminated on the surface of the transparent resin substrate.
As the transparent conductive layer, tin oxide, indium-tin oxide (ITO), antimony-doped tin oxide, or a thin film made of silver (Ag) single layer, or indium-tin oxide and silver were laminated. A thin film formed in a non-pattern (solid form) over the entire surface using a transparent conductive material, or an opaque conductive material such as copper, copper alloy, aluminum or other metal material is formed in a fine mesh pattern. Thus, a conductive mesh layer imparted with transparency can be used. In the present invention, the material and forming method of the transparent conductive layer are not particularly limited, and a conventionally known transparent conductive layer can be appropriately employed. You may use what printed the conductive ink in the pattern form on the transparent base material.
Further, when a conductive mesh layer is used as the transparent conductive layer, it is preferable to blacken the surface of the conductive mesh layer on the viewer side in order to suppress external light reflection. In the following description, an example in which a conductive mesh layer is used as the transparent conductive layer will be described.

(1) Conductive Mesh Layer The conductive mesh layer 16 is a layer that can have an electromagnetic wave shielding function by being electrically conductive, and is itself made of an opaque material, but has a mesh shape with a large number of openings. By processing it into a shape, it is a layer that achieves both electromagnetic shielding performance and light transmittance.
The conductive mesh layer 16 is typically formed by etching a metal foil, but other conductive mesh layers 16 are also significant in electromagnetic shielding performance. Therefore, in this invention, the material and formation method of a conductive mesh layer are not specifically limited, Conventionally well-known various conductive mesh layers can be employ | adopted suitably. For example, a conductive mesh layer formed in a mesh shape from the beginning on a transparent resin substrate using a printing method, a plating method, or the like, or initially, vapor deposition, sputtering on the entire surface of the transparent resin substrate After forming a non-patterned transparent conductive layer using one or more chemical forming methods such as plating or physical or electroless plating, the conductive mesh layer is formed into a mesh shape by etching or the like It does not matter even if it is.

  The conductive mesh layer is not particularly limited as long as it is a substance having sufficient conductivity to exhibit electromagnetic wave shielding performance, but usually a metal layer is preferable in terms of good conductivity, and the metal layer is as described above. It can be formed by vapor deposition, plating, metal foil lamination or the like. Examples of the metal material for the metal layer include gold, silver, copper, aluminum, iron, nickel, and chromium. The metal of the metal layer may be an alloy, and the metal layer may be a single layer or a multilayer. For example, in the case of iron, low carbon steel such as low carbon rimmed steel and low carbon aluminum killed steel, Ni-Fe alloy, Invar alloy, and the like are preferable. On the other hand, when the metal is copper, the metal material is copper or a copper alloy. There are rolled copper foil and electrolytic copper foil as the copper foil, but the thinness and uniformity thereof, the adhesion with the blackened layer, etc. Is preferably an electrolytic copper foil.

  In addition, the thickness of the electroconductive mesh layer by a metal layer is about 1-50 micrometers, Preferably it is 2-15 micrometers. If the thickness is too thin, it will be difficult to obtain sufficient electromagnetic shielding performance due to an increase in electrical resistance, and if the thickness is too thick, it will be difficult to obtain a high-definition mesh shape and the uniformity of the mesh shape will be reduced. . The conductive mesh layer has a thickness of about 2 to 10 μm because it is easy to flatten the conductive mesh layer, and it is easy to obtain a composite filter with less air bubbles and excellent transparency when flattened. It is preferable that

[Mesh shape]
In addition, the shape of the conductive mesh layer as a mesh shape is not particularly limited, but a square shape is typical as the shape of the opening of the mesh. The plan view shape of the opening is, for example, a triangle such as a regular triangle, a square such as a square, a rectangle, a rhombus, or a trapezoid, a polygon such as a hexagon, a circle, an ellipse, or the like. The mesh has a plurality of openings having these shapes, and the openings are usually line-shaped line portions having a uniform width. Usually, the openings and the line portions have the same shape and the same size on the entire surface. As an example of a specific size, the width of the line portion between the openings is preferably 5 to 30 μm in terms of the aperture ratio and the invisibility of the mesh. The size of the opening is [line interval or line pitch] − [line width]. In terms of this [line interval or line pitch], the opening size is 100 μm to 500 μm, and the opening ratio (the total area of the openings / mesh portion) The total area) is preferably 50 to 97% from the viewpoint of compatibility between light transmittance and electromagnetic wave shielding properties. The line pitch may be random between 100 μm and 500 μm.
Note that the bias angle (the angle formed between the mesh line portion and the outer periphery of the conductive mesh layer) may be appropriately set to an angle at which moire is difficult to occur in consideration of the pixel pitch and light emission characteristics of the PDP.

[Grounding area and mesh area]
In addition, the conductive mesh layer 16 has a grounding region other than the central mesh region 161 in the planar direction, like the conductive mesh layer 16 conceptually illustrated in the plan view of FIG. The layer provided with 162 is more preferable in terms of easy grounding. The grounding area is formed on a part or all of the periphery of the image display area so as not to disturb the image display. The mesh area is an area that can cover the entire image display area of the PDP to which the composite filter is applied. The grounding area is an area for grounding. The image display area means at least an area in which the PDP substantially displays an image (substantially image display area). When the PDP is viewed from an observer, the entire inner side of the frame by the outer frame body of the PDP is used. An area may be included for convenience. The reason is that if a black area (border) exists inside the frame and outside the substantial image display area, it is outside the image display area, but the appearance is substantially the image display area as long as it is touched. The difference is that a sense of incongruity occurs.
The grounding region basically does not require a mesh, but a mesh composed of openings may be present for the purpose of preventing warpage of the grounding region.

[Blackening treatment]
The blackening treatment is for preventing light reflection on the surface of the conductive mesh layer, and the black level of the fluoroscopic image due to reflection of external light on the surface of the conductive mesh layer by the blackening treatment surface formed by the blackening treatment. In addition, the visibility of a PDP image is improved by improving the bright room contrast of a fluoroscopic image. The blackening treatment surface is preferably provided on all surfaces of the line portion (linear portion) of the conductive mesh layer. However, in the present invention, at least the observer side and the surface on the outside light incident side of the front and back surfaces are provided. It is preferable to use a blackened surface. Both front and back surfaces and side surfaces (both sides or one side) may be further blackened. The blackening layer may be provided at least on the viewer side. However, when the blackening layer is also provided on the PDP surface side, stray light generated from the PDP can be suppressed, so that the visibility of the image is further improved.
The blackening treatment is performed by either roughening the metal plating layer surface of the blackening layer, imparting light absorption over the entire visible light spectrum (blackening), or using both in combination. . Specifically, as the blackening treatment, a blackening layer is additionally provided on the conductive mesh layer by plating or the like, and the layer constituting the surface itself is changed from the surface to the inside by etching or the like to the blackening layer. May be.

In the present invention, the blackened layer is not particularly limited as long as it exhibits a dark color such as black and satisfies basic physical properties such as adhesion, and a known blackened layer can be appropriately employed.
Therefore, as the blackening layer, an inorganic material such as a metal, an organic material such as a black colored resin, or the like can be used. For example, as the inorganic material, a metal compound such as a metal, an alloy, a metal oxide, or a metal sulfide is used. It is formed as a metal-based layer. As a method for forming the metal layer, various conventionally known blackening methods can be appropriately employed.

  As the blackening layer of the present invention, using a compound composed of three elements of Ni—Cu—O (hereinafter referred to as (Ni—Cu—O) compound) is excellent in adhesion and suitable for etching processing. It is preferable from the viewpoint that it is excellent and has sufficient blackness to absorb external light. In order to absorb external light to the transparent conductive layer and improve the visibility of the display image, a blackened layer is formed on the transparent resin substrate directly or via another layer. Although the formation method of a blackening layer is not specifically limited, It can form suitably by vapor phase film-forming, such as a sputtering method and a vacuum evaporation method. Sputtering is particularly preferred because of its high deposition rate and excellent adhesion. In the sputtering method, Ni—Cu (nickel-copper alloy) is used as a target, an argon atom that is ionized by applying a high voltage while supplying a desired amount of oxygen gas is hit, and the target is ionized and blown away to form a transparent resin base. A blackened layer is formed by depositing on the material. Since the blackening layer according to the present invention has high blackness, it can absorb external light and suppress external light reflection (glare feeling).

  The reflection Y value of the blackened layer is preferably 10 or less. The reflection Y value is measured using a chromaticity meter (CM-3600d manufactured by Minolta) with an observation viewing angle of 10 degrees and an observation light source D65.

[Rust prevention layer]
As the conductive mesh layer, other layers may be appropriately formed or processed as necessary. For example, when the durability against rust is insufficient, a rust prevention layer may be provided.
The rust preventive layer is not particularly limited as long as it is less likely to rust than the conductive mesh layer covered with it, such as an inorganic material such as metal, an organic material such as resin, or a combination thereof. In some cases, the blackened layer is also covered with a rust-preventing layer, so that the particles of the blackened layer can be prevented from falling off and deformed, and the blackness of the blackened layer can be increased. Therefore, in the present invention, it is preferable to provide a rust-preventing layer on the blackened layer from the viewpoint of preventing the blackened layer from dropping or preventing alteration.

A conventionally well-known thing should just be employ | adopted for a rust prevention layer suitably, for example, is a metal thru | or alloys, such as chromium, zinc, nickel, tin, copper, or the layer of a metal compound of a metal oxide. These can be formed by a known plating method or the like.
In addition, the thickness of a rust prevention layer is about 0.001-2 micrometers normally, Preferably it is 0.01-1 micrometer.

(2) Transparent resin base material A transparent resin base material is a layer for reinforcing the electroconductive mesh layer with weak mechanical strength. Therefore, as the transparent resin base material, if it has mechanical strength and light transmittance, a material that appropriately considers performance such as heat resistance may be selected according to the intended use. As a specific example of such a transparent resin base material, a sheet (or film, the same applies hereinafter) made of an organic material such as a resin can be given. The higher the transparency of the transparent resin substrate, the better. However, the light transmittance in the visible light region of 380 to 780 nm is preferably 70% or more, more preferably 80% or more. The light transmittance can be measured using a spectrophotometer (for example, UV-3100PC manufactured by Shimadzu Corporation) and a value measured in the air at room temperature.

  Examples of the transparent resin used as the material for the transparent resin substrate include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, terephthalic acid-isophthalic acid-ethylene glycol copolymer, terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer Polyester resins such as nylon 6, polyamide resins such as nylon 6, polyolefin resins such as polypropylene, polymethylpentene and cycloolefin polymers, acrylic resins such as polymethyl methacrylate, styrene such as polystyrene and styrene-acrylonitrile copolymers Resin, cellulose resin such as triacetyl cellulose, polycarbonate resin and the like.

  These resins are used alone or as a plurality of types of mixed resins (including polymer alloys), and the layer structure of the transparent resin substrate is used as a single layer or a laminate of two or more layers. In the case of a resin film, a uniaxially stretched or biaxially stretched film is more preferable in terms of mechanical strength.

The thickness of the transparent resin substrate may be basically selected according to the application and is not particularly limited, but is usually 12 to 1000 μm, preferably 50 to 500 μm, more preferably 50 to 200 μm. Within such a thickness range, the mechanical strength is sufficient, warping, loosening, breakage, etc. are prevented, and it is easy to supply and process in a continuous belt shape.
In the present invention, as the transparent resin substrate, a plate (thickness of 1000 μm or more) can be used in addition to a resin sheet (thickness of 100 μm or more and less than 1000 μm) or a film (thickness of less than 100 μm).

  In this respect, the transparent resin film is preferably a transparent resin film rather than a resin plate. Among these resin films, polyester resin films such as polyethylene terephthalate and polyethylene naphthalate are preferable in terms of transparency, heat resistance, cost, and the like, and more preferably a biaxially stretched polyethylene terephthalate film.

  Further, in the resin of the transparent resin base material, a known additive, for example, a UV absorber described later, a filler, a plasticizer, an antistatic agent, and the like are appropriately added as necessary. It can be added without departing from the scope.

  The transparent resin base material is appropriately subjected to known easy adhesion treatment such as corona discharge treatment, plasma treatment, ozone treatment, flame treatment, primer treatment, preheat treatment, dust removal treatment, vapor deposition treatment, alkali treatment, etc. You may go.

(3) Adhesive Layer Although the adhesive layer is not shown in FIG. 2, an adhesive layer (or pressure-sensitive adhesive layer) may be used between the conductive mesh layer 16 and the transparent resin substrate 12. The adhesive layer is not particularly limited as long as it is a layer that can bond the conductive mesh layer and the transparent resin base material, but it constitutes the conductive mesh layer. In the case where the metal foil and the transparent resin base material are bonded to each other via an adhesive layer, and then the metal foil is meshed by etching, the adhesive layer preferably has etching resistance. Specifically, polyurethane resins such as polyester urethane, acrylic urethane, polyether urethane, acrylic resin, polyester resin, polyvinyl alcohol alone or a partially saponified product thereof, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer , Polyimide resin, epoxy resin and the like. The adhesive layer (or pressure-sensitive adhesive layer) used in the present invention may be an ultraviolet curable type or a thermosetting type. In particular, a polyurethane resin, an acrylic resin, or a polyester resin is preferable from the viewpoint of adhesion to a transparent resin substrate.

  The transparent resin base material and the metal foil for forming the conductive mesh layer can be bonded by the dry lamination method or the like through the adhesive layer. Moreover, it is preferable that the film thickness of this adhesive bond layer is in the range of 0.5 μm to 50 μm, especially 1 μm to 20 μm. Thereby, a transparent resin base material and a conductive mesh layer can be firmly bonded, and the transparent resin base material is affected by an etching solution such as iron chloride at the time of etching to form the conductive mesh layer. This is because it can be prevented.

4). Surface Protective Layer The surface protective layer used in the present invention protects the surface of the transparent glass substrate in order to reduce background reflection, image whitening, and image contrast degradation due to specular reflection of extraneous light on the glass surface. And a layer having an antireflection function and / or an antiglare function. The latter method of exhibiting the antiglare function includes a method of scattering or diffusing light like a frosted glass to make a background image by extraneous light. In addition, the former method of exhibiting the antireflection function is to provide a single layer having a low refractive index on the surface, or alternately stack a material having a high refractive index and a material having a low refractive index so that the outermost surface is a low refractive index layer. In this way, there is a method of obtaining a good antireflection effect by suppressing the reflection of the surface by making multilayers (multi-coating) and canceling the reflected light at the interface of each layer by interference. The surface protective layer may be formed as a multilayer in addition to a single layer. However, no substrate is interposed between two or more surface protective layers of the present invention.

(1) Anti-glare layer Anti-glare layer (Anti Glare layer, abbreviated as AG layer) is a layer having an anti-glare function, and in order to scatter or diffuse extraneous light, a desired fine uneven shape is formed. The roughening treatment applied to the incident surface is the basis of the function providing means. Examples of the method for directly roughening the surface of the substrate include a method of forming fine irregularities by a sandblasting method, an embossing method, or the like. On the other hand, as a method of roughening by layer formation, an inorganic filler such as silica as a light diffusing particle or an organic material such as a resin particle in a resin binder that is cured by radiation or heat or a combination on a substrate surface. Examples thereof include a method of providing a roughened layer with a coating film containing a filler and a method of forming a porous film having a sea-island structure on the surface of a substrate. As the resin of the resin binder, a curable acrylic resin, an ionizing radiation curable resin, or the like is preferably used because surface strength is desired as the surface layer.
The thickness of the antiglare layer is not particularly limited, but is preferably 0.07 μm or more and 20 μm or less.

(2) Antireflective layer The antireflective layer (Anti Reflection layer, abbreviated as AR layer) is a single low refractive index layer or a low refractive index layer and a high refractive index layer. A multilayer structure in which layers are alternately stacked so as to be positioned at the uppermost layer is generally used, and can be formed by a dry film formation method such as vapor deposition or sputtering, or by using a wet film formation method such as coating. Note that silicon oxide, magnesium fluoride, fluorine-containing resin, or the like is used for the low refractive index layer, and titanium oxide, zinc sulfide, zirconium oxide, niobium oxide, or the like is used for the high refractive index layer. Here, the high (low) refractive index layer means that the refractive index of the layer is relatively higher than that of a layer adjacent to the layer (for example, a transparent glass substrate or a low (high) refractive index layer). It means high (low).

In order to improve the antireflection effect, the refractive index of the low refractive index layer is preferably 1.45 or less. Examples of the material having these characteristics include LiF (refractive index n = 1.4), MgF ₂ (refractive index n = 1.4), 3NaF · AlF ₃ (refractive index n = 1.4), AlF ₃ ( Inorganic materials such as refractive index n = 1.4), Na ₃ AlF ₆ (refractive index n = 1.33), SiO ₂ (refractive index n = 1.45) are made into fine particles, acrylic resin, epoxy resin, etc. Inorganic low-reflective materials, fluorine-based / silicone-based organic compounds, thermoplastic resins, thermosetting resins, radiation-curable resins, and the like can be used.
Further, fine particles having voids may be used for the low refractive index layer. The fine particles having voids form a structure in which fine particles are filled with gas and / or a porous structure containing gas, and are in inverse proportion to the gas occupancy ratio in the fine particles compared to the original refractive index of the fine particles. It means fine particles having a reduced refractive index. The present invention also includes fine particles capable of forming a nanoporous structure inside and / or at least part of the surface depending on the form, structure, aggregation state, and dispersion state of the fine particles inside the coating film. It is. The fine particles having voids may be either inorganic or organic, and examples thereof include metals, metal oxides, and resins, and preferably silicon oxide (silica) fine particles.

Furthermore, a material in which a sol obtained by dispersing ultrafine silica particles of 5 to 30 nm in water or an organic solvent and a fluorine-based film forming agent can be used. The sol in which the ultrafine silica particles of 5 to 30 nm are dispersed in water or an organic solvent is obtained by a method of dealkalizing alkali metal ions in alkali silicate salt by ion exchange or the like, or neutralizing alkali silicate salt with mineral acid. A known silica sol obtained by condensing active silicic acid known by the method, etc., a known silica sol obtained by condensing alkoxysilane with hydrolysis in an organic solvent in the presence of a basic catalyst, and the above-mentioned An organic solvent-based silica sol (organosilica sol) obtained by substituting water in the aqueous silica sol with an organic solvent by a distillation method or the like is used. These silica sols can be used in both aqueous and organic solvent systems. In producing the organic solvent-based silica sol, it is not necessary to completely replace water with the organic solvent. The silica sol contains solids 0.5 to 50 wt% concentration as SiO _2. Various structures such as a spherical shape, a needle shape, and a plate shape can be used for the structure of the ultrafine silica particles in the silica sol. As the film forming agent, alkoxysilane, metal alkoxide, hydrolyzate of metal salt, or fluorine-modified polysiloxane can be used. According to a preferred embodiment of the low refractive index layer, “fine particles having voids” are preferably used.

  The low-refractive index layer is prepared by diluting the above-described materials in, for example, a solvent, and forming a coating film on the high-refractive index layer by a wet coating method such as spin coating, roll coating, or printing. In the case of ultraviolet rays, it can be obtained by curing with the above-described photopolymerization initiator. Alternatively, the low refractive index layer may be formed on the high refractive index layer by a vapor phase method such as vacuum deposition, sputtering, plasma CVD, or ion plating.

  The high refractive index layer is formed by using a binder resin having a high refractive index in order to increase the refractive index, adding ultrafine particles having a high refractive index to the binder resin, or using these in combination. To do. The refractive index of the high refractive index layer is preferably in the range of 1.55 to 2.70.

  As the resin used for the high refractive index layer, any resin can be used as long as it is transparent, and a thermosetting resin, a thermoplastic resin, a radiation (including ultraviolet) curable resin, or the like can be used. Thermosetting resins include phenolic resin, melamine resin, polyurethane resin, urea resin, diallyl phthalate resin, guanamine resin, unsaturated polyester resin, aminoalkyd resin, melamine-urea co-condensation resin, silicon resin, polysiloxane resin, etc. A curing agent such as a crosslinking agent and a polymerization initiator, a polymerization accelerator, a solvent, a viscosity modifier and the like can be added to these resins as necessary.

As the ultrafine particles having a high refractive index, for example, ZnO (refractive index n = 1.9), TiO ₂ (refractive index n = 2.3 to 2.7), which can also obtain an ultraviolet shielding effect, Fine particles of CeO ₂ (refractive index n = 1.95), antimony-doped SnO ₂ (refractive index n = 1.95) or antistatic effect, which can prevent dust adhesion. Examples thereof include fine particles of ITO (refractive index n = 1.95). Other fine particles include Al ₂ O ₃ (refractive index n = 1.63), La ₂ O ₃ (refractive index n = 1.95), ZrO ₂ (refractive index n = 2.05), Y ₂ O _3. (Refractive index n = 1.87). These fine particles are used singly or in combination, and those in the form of a colloid dispersed in an organic solvent or water are good in terms of dispersibility, and the particle size is 1 to 100 nm, the transparency of the coating film To preferably 5 to 20 nm.
In order to provide a high refractive index layer, the above-described material is diluted with a solvent, for example, applied onto a substrate by a method such as spin coating, roll coating, or printing, dried, and then subjected to heat or radiation (in the case of ultraviolet rays, the above-mentioned The photopolymerization initiator may be used for curing.
The thickness of the antireflection layer is not particularly limited, but is usually about 1/4 (95 to 195 nm) of the wavelength of visible light (380 to 780 nm) to be prevented from being reflected.

The surface protective layer in the present invention has an antiglare function and / or an antireflection function as described above, and may be appropriately provided with an ultraviolet shielding function, an antifouling function, or the like.
(3) Ultraviolet absorbing layer In the present invention, the ultraviolet absorbing layer is a layer to which an ultraviolet absorbing function is imparted by containing an ultraviolet absorber, and is included in the near infrared absorbing layer according to the present invention. In order to prevent the deterioration, it is preferable that the layer be included in the near-infrared absorbing layer or be disposed closer to the viewer than the near-infrared absorbing layer. In addition, in order to provide a surface protective layer on one surface of the transparent glass substrate, when the ultraviolet absorbing layer containing an ultraviolet absorber is formed on the surface protective layer forming surface side, an independent layer may be used. Alternatively, the ultraviolet absorbing layer and the surface protective layer may be used as a surface protective layer.
Of course, it is also possible to add an ultraviolet absorber to the glass substrate. However, it cannot be recommended much in terms of restrictions on usable UV absorbers (necessary heat resistance that does not deteriorate or deteriorate in high-temperature molten glass), and manufacturing costs rise.

As the ultraviolet absorber, a substance having high transparency in the visible light region and sufficient absorption in the ultraviolet region (wavelength of 380 nm or less) is selected. For example, a known compound made of an organic compound such as benzotriazole or benzophenone, an inorganic compound made of finely divided zinc oxide, cerium oxide or the like can be used.
When an independent ultraviolet absorbing layer is formed, a composition obtained by adding such an ultraviolet absorbent to a binder resin may be applied and formed by a known method. Examples of the binder resin include thermoplastic resins such as polyester resins, polyurethane resins, and acrylic resins, thermosetting resins or ionizing radiation curable resins made of monomers such as epoxy, acrylate, and methacrylate, and prepolymers. Examples thereof include curable resins such as liquid curable urethane resins.
Also, commercially available UV cut filters such as “Sharp Cut Filter SC-38” (trade name), “SC-39”, “SC-40” manufactured by Fuji Photo Film Co., Ltd., “Acryprene” manufactured by Mitsubishi Rayon Co., Ltd. (Product name) or the like can also be used.
Although the thickness of an ultraviolet absorption layer is not specifically limited, 1.0 micrometer or more and 30 micrometers or less are preferable, More preferably, they are 10 micrometers or more and 20 micrometers or less.

(4) Other functional layers In addition, when a composite filter is used, the surface protective layer adheres to the surface on the viewer (viewer) side due to inadvertent contact or contamination from the environment. In order to prevent this, or to make it easy to remove even if it adheres, a contamination-preventing layer or an antistatic layer may be formed. For example, a fluorine-based coating agent, a silicon-based coating agent, a silicon / fluorine-based coating agent, or the like is used for imparting the anti-contamination function, and among these, a silicon / fluorine-based coating agent is preferably applied. The thickness of these antifouling layers is preferably 100 nm or less, more preferably 10 nm or less, and even more preferably 5 nm or less. When the thickness of these antifouling layers exceeds 100 nm, the initial value of antifouling properties is excellent, but the durability is inferior. 5 nm or less is the most preferable from the balance of antifouling property and its durability.
When providing an antifouling layer as an independent layer, it is preferable to provide it on the outermost surface of a surface protective layer such as an antiglare layer or an antireflection layer.

Moreover, it is preferable that the surface protective layer used in the present invention is formed as a single layer having a plurality of functions.
For example, in addition to the antiglare function, it may further have a function of preventing specular reflection of extraneous light. As a specific example, when the antiglare layer is an antireflection layer, the uppermost antiglare layer in the surface protective layer is made to have a lower refractive index than the layer immediately below it by the method described in the above antireflection layer. What is necessary is to rate.

  In the composite filter according to the present invention, in addition to the surface protective layer having an antiglare function and / or an antireflection function, other functional layers such as an antifouling layer, a neon light absorbing layer, and an ultraviolet absorbing layer are independently provided. In this case, from the viewpoint of realizing multiple functions with as few layers as possible, the anti-glare layer 30 or the anti-reflection layer 40 shown in FIG. 3 on the viewer 70 side (referred to as position A), the anti-glare layer 30 or the anti-reflection layer. 40 and the transparent glass substrate 10 (referred to as position B), or at least one place arbitrarily selected from the transparent glass substrate 10 side (referred to as position C) of the near-infrared absorbing layer 20 for each position. It is preferable to provide only one additional functional layer, and it is particularly preferable to provide only one layer at one or both of position A or position B. However, no substrate other than the transparent glass substrate 10 is interposed between two or more layers of the present invention. These other functional layers are preferably provided at the position A from the viewpoint of expressing their functions. Moreover, it is preferable that the anti-glare layer 30, the antireflection layer 40, and / or the near-infrared absorption layer 20 contain an ultraviolet absorber and also have an ultraviolet absorption function.

5). Characteristics of Composite Filter for Display As described above, each layer has been described as an example. However, when the composite filter for display of the present invention is applied to the front surface of a plasma display panel which is a typical application, the plasma display panel is xenon. It is preferable that the light transmittance in the near infrared region generated when emitting light using gas discharge, that is, in the wavelength region of 800 to 1100 nm, is 30% or less, more preferably 20% or less, and particularly preferably 10% or less.
In addition, when the composite filter for display of the present invention is applied to the front surface of a plasma display panel, which is a typical application, neon atoms are excited when the plasma display panel emits light using xenon gas discharge. Thereafter, the neon light emitted when returning to the ground state, that is, the light transmittance in the wavelength region of 570 to 610 nm is preferably 50% or less, more preferably 30% or less.
The composite filter for display of the present invention desirably has a sufficient light transmittance, that is, a visible light transmittance of 30% or more, and more preferably 40% or more in a visible light region, that is, a wavelength region of 380 to 780 nm.
In addition, the light transmittance in this invention can be measured with a spectrophotometer (for example, product number: UV-3100PC, company name: Shimadzu Corporation) based on JIS-Z8701.

  The composite filter for display of the present invention has excellent optical filter function durability, and the spectral characteristics attributed to the deterioration of the light absorber hardly occur even when used for a long time under high temperature and high humidity. Specifically, the initial state of the produced composite filter, the normal environment of the composite filter (23 ° C., humidity 10% or less), the heat resistant environment (80 ° C., humidity 10% or less), and the moisture and heat resistant environment (60 ° C. 95%) Comparison of spectral characteristics (transmittance T, chromaticity (x, y)) after 1000 hours under three conditions (RH), the transmittance change ΔT at 380 nm to 800 nm is 20% or less. Further, it is preferably 10% or less, and the transmittance change ΔT at 800 nm to 1000 nm is preferably 10% or less, and more preferably 5% or less. Further, the changes Δx and Δy of the chromaticity (x, y) of the composite filter are both 0.01 or less, more preferably 0.007 or less.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

  Hereinafter, the present invention will be described more specifically with reference to examples. These descriptions do not limit the present invention.

<Example 1>
(Formation of conductive mesh layer)
As a transparent resin base material, a continuous belt-like uncolored transparent biaxially stretched polyethylene terephthalate (PET) film (A4300: trade name, manufactured by Toyobo Co., Ltd.) having a thickness of 100 μm was prepared. Next, copper deposition was performed on this PET surface to laminate a metal layer. A blackening layer (Ni—Cu—O blackening layer) made of an alloy containing nickel, copper and oxygen was formed thereon by vacuum sputtering. The sheet resistance was 0.01Ω / □.
Next, in the laminate, the metal layer and the blackened layer are etched into a PDP image display area using a transparent conductive layer composed of a mesh-shaped area including an opening and a line by etching using a photolithography method. A transparent conductive layer was formed correspondingly, and a conductive mesh layer having a frame-shaped mesh-free grounding region on the outer edge surrounding the circumference of the mesh-shaped region was formed. The mesh shape was a square lattice having square openings, the line width was 10 μm, and the opening width (side length of the square) was 290 μm. One rectangular area having the mesh shape corresponds to one screen of the PDP. Such rectangular mesh-like areas are arranged on one side at intervals of 30 mm in the form of a continuous band, and margins having a width of 15 mm are respectively formed on both sides of the arrangement of the mesh-like areas, and the width of the grounding area at the peripheral part is increased. It was 15 mm.
Specifically, the etching was performed consistently from resist formation, masking to etching on the laminate using a production line for a color TV shadow mask. That is, after a photosensitive etching resist is applied to the entire surface of the transparent conductive layer of the laminate, a mask having a desired mesh pattern is closely exposed, developed, hardened, and baked to obtain a region corresponding to a mesh line portion. After the resist layer is processed into a pattern in which the resist layer remains on the area corresponding to the opening and the resist layer does not exist, the aqueous solution of ferric chloride is used to form the metal layer and black in the resist layer non-formation area. The chemical layer was removed by etching to form a mesh-shaped opening, followed by sequential washing with water, stripping of the resist, washing and drying.

(Formation of near-infrared absorbing layer (adhesive layer))
Next, a near-infrared absorbing layer (adhesive layer) to which various light absorbers were added was formed on the surface on the conductive mesh layer side of the continuous band-shaped laminate. 0.25 parts by weight of a curing agent (manufactured by Soken Chemical Co., Ltd., E-5XM) and cesium-containing tungsten oxide (Cs0) with respect to 100 parts by weight of an acrylic adhesive (manufactured by Soken Chemical Co., Ltd., SK Dyne 2094) .33WO3) content 18.5 wt% suspension (manufactured by Sumitomo Metal Mining Co., Ltd., YMF-02; average dispersed particle size 800 nm or less) 11.32 parts by weight, neon light absorber (manufactured by Yamada Chemical Co., Ltd., TAP-2: tetraazaporphyrin-based dye) 0.045 parts by weight, color correction dye (manufactured by Nippon Kayaku Co., Ltd., KAYASET RED A2G) 0.3 parts by weight are added and dispersed sufficiently, and a near-infrared absorbing layer A composition was prepared.
And it apply | coated so that the thickness at the time of drying may be set to 25 micrometers with the die coater with respect to the surface at the side of the conductive mesh layer of the said laminated body, and it is 100 degreeC for 1 minute in the oven which hits dry air with a wind speed of 5 m / sec. It dried and formed the near-infrared absorption layer, and obtained the sheet | seat by which the near-infrared absorption layer was laminated | stacked on the said laminated body in the continuous belt-like state. The surface of the near-infrared absorbing layer was further protected by attaching a releasable release film.
In addition, the near-infrared absorbing layer was formed in a partial pattern by an intermittent coating method so that the ground area of the conductive mesh layer was not covered but the mesh area was covered.
(Lamination on glass plate)
A sheet in which the near-infrared absorbing layer was laminated on the laminate was cut out to the same size as the glass plate. The release film on the surface of the near infrared absorbing layer was peeled off and bonded to the glass surface to produce a composite filter.

[Compound filter evaluation]
The produced composite filter for display had a light transmittance of 10% or less and a visible light transmittance of 47% in the wavelength region of 800 to 1100 nm. In addition, the light transmittance in this invention was measured with the spectrophotometer (The Shimadzu Corporation make, UV-3100PC) based on JIS-Z8701.

  Furthermore, the initial state of the produced composite filter for display, and the normal environment (23 ° C., humidity 10% or less), heat-resistant environment (80 ° C., humidity 10% or less), and heat-resistant environment (60 ° C. 95% RH) of the composite filter. ) Was measured using a spectrophotometer (manufactured by Shimadzu Corporation, UV-3100PC) after 1000 hours. From the initial state and the measured values of transmittance T and chromaticity (x, y) after 1000 hours under the above three conditions, the difference Δx in transmittance change ΔT and chromaticity (x, y) values Δy was determined.

  As a result, 1000 hours passed under the initial conditions and the normal environment of the composite filter (23 ° C., humidity 10% or less), heat resistant environment (80 ° C., humidity 10% or less), and heat and humidity resistant environment (60 ° C. 95% RH). In all comparisons, the transmittance change ΔT at 380 nm to 800 nm was 9% or less, and the transmittance change ΔT at 800 nm to 1000 nm was 3% or less. Further, the changes Δx and Δy of the chromaticity (x, y) of the filter were both 0.004 or less.

<Example 2>
A composite filter was prepared in the same manner as in Example 1 except that the glass surface was roughened by sandblasting and a sheet in which the near-infrared absorbing layer was laminated on the laminate of Example 1 was bonded to a non-roughened surface. Produced.

The obtained composite filter was evaluated in the same manner as in Example 1. As a result, the produced composite filter had a light transmittance of 10% or less and a visible light transmittance of 47% in the wavelength region of 800 to 1100 nm.
In addition, after 1000 hours in the initial state and the normal environment of the composite filter (23 ° C., humidity 10% or less), heat-resistant environment (80 ° C., humidity 10% or less), and humidity-heat resistant environment (60 ° C. 95% RH) In any case, the transmittance change ΔT at 380 nm to 800 nm was 9% or less, and the transmittance change ΔT at 800 nm to 1000 nm was 3% or less. Further, the changes Δx and Δy of the chromaticity (x, y) of the filter were both 0.004 or less.

<Example 3>
(Process of laminating an antiglare layer on the glass surface)
An antiglare layer was formed on the transparent resin substrate. Specifically, first, as an ionizing radiation curable resin, 70 parts by mass of pentaerythritol triacrylate (manufactured by Nippon Kayaku Co., Ltd., refractive index 1.49) and 30 parts by mass of isocyanuric acid EO-modified diacrylate (Toago) 10.0 parts by mass of Synthetic Co., Ltd., refractive index 1.51), acrylic polymer (Mitsubishi Rayon Co., Ltd., molecular weight: 75,000), 5.0 of the trade name Irgacure 184 as a photocuring initiator In addition, 15.0 parts by mass of styrene beads (manufactured by Soken Chemical Co., Ltd., particle size 3.5 μm, refractive index) as an ultraviolet curable resin blended with parts by mass (Ciba Gaigi Co., Ltd.) 1.60), 0.01 part by mass (made by The Inktec Co., Ltd.) as a trade name “10-28” as a leveling agent, 127.5 parts by mass of toluene, and 54.6 parts by mass of cyclohexanone, And a coating solution was thoroughly mixed. This coating solution was filtered through a polypropylene filter having a pore diameter of 30 μm to prepare a coating solution for forming an antiglare layer. Next, after coating the coating solution on the surface of the transparent resin substrate so as to have a film thickness of 7 μm, the coating solution is dried by heating in an oven at 50 ° C., and a UV irradiation apparatus (fusion UV system) in an N ₂ atmosphere. Using an H bulb manufactured by Japan Co., Ltd. as a light source, it was cured by irradiation with ultraviolet rays (integrated light amount 200 mJ) to form an antiglare layer. The antiglare layer film was bonded to the glass surface of the composite filter prepared in Example 1 using a transparent adhesive (trade name: TU-41A manufactured by Yodogawa Paper Mill) to prepare a composite filter.

The obtained composite filter was evaluated in the same manner as in Example 1. As a result, the produced composite filter had a light transmittance of 10% or less and a visible light transmittance of 47% in the wavelength region of 800 to 1100 nm.
In addition, after 1000 hours in the initial state and the normal environment of the composite filter (23 ° C., humidity 10% or less), heat-resistant environment (80 ° C., humidity 10% or less), and humidity-heat resistant environment (60 ° C. 95% RH) In any case, the transmittance change ΔT at 380 nm to 800 nm was 9% or less, and the transmittance change ΔT at 800 nm to 1000 nm was 3% or less. Further, the changes Δx and Δy of the chromaticity (x, y) of the filter were both 0.004 or less.

<Comparative Example 1>
In the formation of the near-infrared absorption layer of Example 1, a cesium-containing tungsten oxide (Cs _0.33 WO ₃ ) content 18.5 wt% suspension (Sumitomo Metal Mining Co., Ltd., YMF-02) 1.32 Instead of using parts by weight, 0.534 parts by mass of a trade name IRG-022 (manufactured by Nippon Kayaku Co., Ltd.), which is a diimmonium dye, and a trade name EXCOLOR IR-12A 0, which is a phthalocyanine NIR absorbing dye. A composite filter was produced in the same manner as in Example 1, except that 298 parts by mass and 0.158 parts by mass of the trade name EXCOLOR IR-14 (the above, manufactured by Nippon Shokubai Co., Ltd.) were used.

The obtained composite filter of Comparative Example 1 was evaluated in the same manner as in Example 1. As a result, the light transmittance in the wavelength range of 800 to 1100 nm of the produced composite filter was 7%. The visible light transmittance was 63%.
Further, in a comparison between the initial state and the normal environment (23 ° C., humidity 10% or less) of the composite filter after 1000 hours, the transmittance change ΔT at 380 nm to 800 nm is 1% or less and 800 nm. The transmittance change ΔT at ˜1000 nm was 1% or less. Further, the changes Δx and Δy of the chromaticity (x, y) of the filter were both 0.001 or less.
Further, in comparison between the initial state and the heat resistant environment (80 ° C., humidity 10% or less) after 1000 hours, the transmittance change ΔT at 380 nm to 800 nm exceeds 12%, and at 800 nm to 1000 nm. The transmittance change ΔT was over 15%. Further, the changes Δx and Δy of the chromaticity (x, y) of the filter were 0.03 or more.
In addition, the transmittance change ΔT at 380 nm to 800 nm exceeds 10% and the transmission at 800 nm to 1000 nm is compared between the initial state and after 1000 hours under conditions of moisture and heat resistance (60 ° C. and 95% RH). The rate change ΔT was over 8%. Further, the changes Δx and Δy of the chromaticity (x, y) of the filter were 0.02 or more.

It is sectional drawing which showed typically an example of the composite filter for a display which concerns on this invention. It is sectional drawing which showed typically another example of the composite filter for a display which concerns on this invention. It is sectional drawing which showed typically another example of the composite filter for a display which concerns on this invention. It is sectional drawing which showed typically another example of the composite filter for a display which concerns on this invention. It is sectional drawing which showed typically another example of the composite filter for a display which concerns on this invention. It is sectional drawing which showed typically another example of the composite filter for a display which concerns on this invention. It is sectional drawing which showed typically another example of the composite filter for a display which concerns on this invention. It is a top view of an example of a see-through conductive layer used for the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Composite filter for display 10 Transparent glass base material 12 Transparent resin base material 13 Blackening layer 16 Conductive mesh layer 17 Conductive member 18 Gasket 20 Near-infrared absorption layer (adhesive layer)
30 Antiglare layer 40 Antireflection layer 50 Transparent conductive layer 60 Plasma display 70 Observer side 161 Mesh area 162 Grounding area

Claims (12)

  A near-infrared absorbing layer containing a binder component and a transparent conductive layer are laminated in this order on one side of the transparent glass substrate, and the near-infrared absorbing layer has a general formula MxWyOz (however, , M elements are H, He, alkali metals, alkaline earth metals, rare earth elements, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re, Be, One or more elements selected from Hf, Os, Bi, and I, W is tungsten, O is oxygen, 0.001 ≦ x / y ≦ 1.1, 2.2 ≦ z / y ≦ 3.0 It contains composite tungsten oxide fine particles represented by Display for the composite filter to.   The composite filter for display according to claim 1, wherein the transparent conductive layer is a conductive mesh layer.   The composite filter for display according to claim 2, wherein a part of a peripheral edge of the conductive mesh layer is exposed.   The near-infrared absorbing layer is laminated on the surface of the transparent glass substrate on the display panel side, and an anti-glare function is imparted to the surface on the observer side of the transparent glass substrate. The composite filter for display according to claim 1.   The transparent conductive substrate of the electromagnetic wave shielding sheet provided with a transparent conductive layer on one surface side of the transparent resin substrate through the near-infrared absorbing layer on the surface of the transparent glass substrate on the viewer side is used as the transparent glass substrate. A surface protective layer having an antiglare function and / or an antireflection function is laminated on the surface of the electromagnetic wave shielding sheet on the transparent resin substrate side of the electromagnetic wave shielding sheet. 5. The composite filter for display according to any one of 4 above.   The composite filter for display according to any one of claims 1 to 5, wherein the surface protective layer and / or the near-infrared absorbing layer contains an ultraviolet absorber.   The transparent conductive substrate of the electromagnetic wave shielding sheet provided with a transparent conductive layer on one surface side of the transparent resin substrate through the near-infrared absorbing layer on the surface of the transparent glass substrate on the viewer side is used as the transparent glass substrate. A grounding region that is laminated so as to face each other and is not covered with a near-infrared absorbing layer is provided on at least a part of the peripheral portion of the transparent conductive layer, and the transparent glass substrate and the transparent conductive material are provided in the grounding region. A conductive member that contacts the transparent conductive layer is interposed between the layers, and the conductive member forms a conduction path that extends from the surface on the viewer side of the transparent glass substrate to the surface on the display panel side. The composite filter for display according to claim 1, wherein the composite filter is for display.   The composite filter for display according to any one of claims 1 to 7, wherein the near-infrared absorbing layer further contains a neon light absorber and / or a color correction pigment.   The composite filter for display according to any one of claims 1 to 8, wherein an average dispersed particle size of the composite tungsten oxide fine particles is 800 nm or less.   The composite filter for a display according to any one of claims 1 to 9, wherein the composite tungsten oxide fine particles include one or more crystal structures of hexagonal, tetragonal, and cubic crystals. .   11. The general formula MxWyOz representing the composite tungsten oxide fine particles, wherein the M element is Cs (cesium), and the composite tungsten oxide fine particles have a hexagonal crystal structure. A composite filter for display according to claim 1.   The surface of the composite tungsten oxide fine particles is coated with an oxide containing one or more elements selected from Si, Ti, Zr, and Al. The composite filter for display according to one item.

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