JP4125195B2 - Optical filter for display and display surface structure. - Google Patents

Description

The present invention is an optical filter for a display that can be bonded to the front side of a display panel, that is, a viewer, and more specifically, for a display suitable for being directly bonded to the front side of a plasma display (referred to as “PDP”) panel. The present invention relates to an optical filter.

  In recent years, a plasma display (referred to as “PDP”) has attracted attention as one of large flat panel displays, and its market is rapidly rising as an alternative to a home-use CRT television.

  Conventionally, this type of display structure has a tempered glass base on the front side of the PDP panel that emits red (R), green (G), and blue (B) display light in order to protect the PDP panel from external impacts and the like. The optical filter is generally formed by providing a gap between the optical filter and the PDP panel and arranging the laminated body in an outer casing.

However, when a gap is interposed between the PDP panel and the optical filter, a double reflection phenomenon occurs in which external light incident on the display surface from the outside is reflected by the optical filter front surface and the front surface of the PDP panel and is reflected multiple times. There was a problem of deteriorating the display image quality of the panel. For this reason, recently, a configuration in which an optical filter is directly bonded onto a PDP panel via an adhesive layer has been disclosed (see Patent Document 1 and Patent Document 2).
JP-A-11-119666 JP 2002-251144 A

  However, when the optical filter is directly bonded on the display panel, there are the following problems.

  Compared to a structure in which an optical filter is laminated with a gap between the PDP panel and the structure, the buffering effect (impact resistance) is structurally inferior, so the impact resistance performance for protecting the PDP panel from external impacts is poor. There was a risk of becoming sufficient.

  In addition, in the case of PDP, electromagnetic waves are generated with driving, and even a slight external leakage may adversely affect the human body and surrounding equipment. For example, a transparent elastic adhesive is interposed on the front surface of the PDP. A means for preventing electromagnetic wave leakage to the viewer side, such as laminating a conductive mesh (so-called “electromagnetic wave shielding film”) made of metal fibers having a wire diameter of 1 μm to 1 mm, is required (see Patent Document 1). However, the mesh surface of this type of electromagnetic wave shielding film has irregularities, and when an optical filter is bonded to the irregular surface via an adhesive, bubbles are generated in the adhesive and the reflection of the PDP panel is reduced. . Therefore, it is necessary to perform some degassing treatment after the optical filter is adhered, which complicates the work process and contributes to high cost.

  In addition, when an optical filter is directly bonded to a PDP panel, conventionally used adhesives or pressure-sensitive adhesives have a slow progress of wetting and often require high pressure or high temperature for bonding, and are therefore expensive. The PDP panel module may be damaged.

  Furthermore, when optical filters are directly bonded, they are peeled off so as not to damage expensive panel modules, such as when bonding fails due to foreign object biting or misalignment, or when filter replacement becomes necessary. Although it is necessary, the pressure-sensitive adhesives and adhesives that have been used in the past generally have a strong adhesive force, and few of them can be easily peeled off.

  In view of the above-described problems, the present invention is an optical filter that can be directly attached to the front side of a display panel, has excellent impact resistance to protect the display panel from external impact, and easily does not require high pressure or high temperature. Even if the surface to be bonded to which the optical filter is bonded, such as the mesh surface of the electromagnetic wave shielding film, has unevenness, it can be bonded cleanly without generating bubbles, yet it peels easily An optical filter for a display that can also be provided is provided.

  The present invention is an optical filter that is bonded to the front side of a display panel, and is used as a bonding layer for bonding to the front surface of the panel of the display panel or any layer laminated on the front surface of the panel, or optical We propose an optical filter for display comprising a transparent gel pressure-sensitive adhesive layer made of a transparent gel-like pressure-sensitive adhesive (hereinafter referred to as “transparent gel pressure-sensitive adhesive”) as a bonding layer for bonding the layers constituting the filter.

In the present invention, “front side” or “front side” means the viewer side or viewer side surface, and “back side” or “back side” means the side opposite to the viewer side or viewer. The side opposite to the side is meant.
The “display panel” includes a liquid crystal display, an organic EL display, a CRT display, and other displays in addition to a plasma display (referred to as “PDP”).

  The “transparent gel adhesive” constituting the transparent gel adhesive layer is characterized in that the first characteristic is that the three-dimensional crosslinked polymer is swollen by a liquid containing a plasticizer and inorganic fine particles. The plasticizer is a liquid having a freezing point of −20 ° C. or less, and is characterized by being contained in the gel in an amount of 10 to 70% by weight. The inorganic fine particles have a primary average particle size of 200 nm or less. The third characteristic is that the gel is contained in an amount of 1 to 15% by weight, and the resin constituting the three-dimensional crosslinked polymer (uncrosslinked base polymer) has a glass transition temperature (Tg) of −20 ° C. Hereinafter, the fourth characteristic is that the melt viscosity at 130 ° C. is 50000 mPa · s or more, and in a test according to JIS Z0237, the load is 490 mN (50 gf) × 2 hours, the holding power at 40 ° C. is 5 mm. The fifth characteristic is as follows (claim 1).

  As an example of the optical filter for display of the present invention, a visible light low reflection layer, a near-infrared cut layer, an image quality correction layer, an electromagnetic wave shielding layer, a moisture permeable layer, on one side or both sides of a transparent substrate made of a transparent film or sheet. It is provided with a filter body formed by laminating any one of the prevention layers, or a plurality of layers selected from a combination of two or more selected from these layers, and a transparent gel adhesive layer is laminated on the back surface of the filter body. An optical filter for display having the structure can be cited.

More specifically, a near-infrared cut layer, an image quality correction layer, and a visible light low reflection layer are sequentially laminated on the front surface of the transparent substrate, and a moisture permeation prevention layer is laminated on the back surface (the surface on the bonding side) of the transparent substrate. An optical filter for display (see FIG. 1), in which a transparent gel adhesive layer is laminated on the back surface of the moisture permeation preventive layer,
Provided with a filter body in which a visible light low reflection layer is laminated on the front surface of the transparent substrate, and a moisture permeation preventing layer, a near-infrared cut layer, and an image quality correction layer are sequentially laminated on the back surface of the transparent substrate. Examples thereof include an optical filter for display (see FIG. 2) in which a transparent gel adhesive layer is laminated.

As another example, an electromagnetic wave shielding layer is provided as the backmost surface side layer of the filter body, and one side edge of the conductive member is connected to the conductive surface (back surface) of the electromagnetic wave shielding layer. And the other side edge of the conductive member is located in the forefront of the filter body,
An optical filter for display having a configuration in which a transparent gel adhesive layer is laminated on the back surface of the filter main body with the one side edge portion of the conductive member interposed can be cited (claim 3).
Here, the conductive member is not particularly limited as long as it is a material capable of conducting electricity. Moreover, the form is also arbitrary and may be a tape shape, a film or a sheet shape, a linear shape, or other shapes described later.

Specifically, a near infrared cut layer, an image quality correction layer, and a visible light low reflection layer are sequentially laminated on the front surface of the transparent substrate, while a moisture permeation preventing layer and an electromagnetic wave shielding layer are sequentially laminated on the back surface of the transparent substrate. The filter main body is provided, the end surface of the filter main body is covered with a conductive member, and one side edge of the conductive member is folded into the conductive surface (back surface in the figure) of the electromagnetic wave shielding layer. A display having a configuration in which the other side edge is folded into the forefront of the filter body and a transparent gel adhesive layer is laminated on the back of the filter body with the one side edge of the conductive member interposed Optical filter (see FIG. 3),
A filter body comprising a low visible light reflection layer laminated on the front surface of a transparent substrate, and a moisture permeation preventing layer, a near-infrared cut layer, an image quality correction layer, and an electromagnetic wave shielding layer sequentially laminated on the back surface of the transparent substrate. The end surface portion of the conductive member is covered with a conductive member, one side edge portion of the conductive member is folded into the conductive surface (back surface in the figure) of the electromagnetic wave shielding layer, and the other side edge portion of the conductive member is a filter. Optical filter for display having a configuration in which a transparent gel adhesive layer is laminated on the back surface of the filter body with the one side edge of the conductive member interposed between the front surface of the body and the conductive member (see FIG. 4). ) And the like.

As another configuration example, an optical filter to be bonded to the front side of the display panel, comprising at least an electromagnetic wave shielding layer on one side or both sides of the transparent substrate,
The electromagnetic wave shielding layer is composed of an electromagnetic wave shielding film or sheet provided with a mesh part consisting of a line part connected to the peripheral part on the inner part leaving the peripheral part of the film or sheet made of a conductive material, An optical filter for display having a structure in which a transparent gel adhesive layer is laminated on the mesh portion and the peripheral portion of the electromagnetic wave shielding film or sheet is exposed can be mentioned.

More specifically, on the front surface of the transparent substrate, a moisture permeation preventive layer, a near-infrared cut layer, an image quality correction layer, an electromagnetic wave shielding layer, a transparent gel adhesive layer, and a visible light low reflection layer are sequentially laminated, while the back surface of the transparent substrate. Comprising a filter body in which a moisture permeation preventive layer is sequentially laminated, and a transparent gel adhesive layer laminated on the back surface of the moisture permeation preventive layer, wherein the electromagnetic wave shielding layer is made of a conductive material. The film or sheet is composed of an electromagnetic wave shielding film or sheet in which a mesh part composed of a line part connected to the peripheral part is formed on the inner part leaving the peripheral part of the sheet, and a transparent gel adhesive layer is laminated on the mesh part. And the optical filter for display (refer FIG. 5) provided with the structure by which the peripheral part of an electromagnetic wave shielding film thru | or sheet | seat is exposed to the front side,
A moisture permeation preventing layer, an electromagnetic wave shielding layer, a transparent gel adhesive layer, and a visible light low reflection layer are sequentially laminated on the front surface of the transparent substrate, and a moisture permeation preventing layer, a near-infrared cut layer, and an image quality correction layer are laminated on the back surface of the transparent substrate. An optical filter for display comprising a filter body formed by laminating sequentially and laminating a transparent gel adhesive layer on the back surface of the image quality correction layer, wherein the electromagnetic wave shielding layer is a peripheral portion of a film or sheet made of a conductive material Is formed from an electromagnetic wave shielding film or sheet in which a mesh part composed of a line part connected to the peripheral edge part is formed on the inner part, and a transparent gel adhesive layer is laminated on the mesh part, and the electromagnetic wave shielding film or sheet The optical filter for display (refer FIG. 6) provided with the structure by which the peripheral part is exposed to the front side,
A moisture permeation preventing layer, an electromagnetic wave shielding layer, a transparent gel adhesive layer, a near-infrared cut layer, an image quality correction layer, and a visible light low reflection layer are sequentially laminated on the front surface of the transparent substrate, and a moisture permeation preventing layer is laminated on the back surface of the transparent substrate. An optical filter for a display comprising a transparent gel adhesive layer laminated on the back surface of the image quality correction layer, the electromagnetic wave shielding layer leaving a peripheral portion of a film or sheet made of a conductive material. The inner part is composed of an electromagnetic shielding film or sheet in which a mesh part composed of a line part connected to the peripheral part is formed, and a transparent gel adhesive layer is laminated on the mesh part, and the peripheral part of the electromagnetic shielding film or sheet The part can be exemplified by an optical filter for display (see FIG. 7) having a structure exposed on the front side.

The present invention also has a display surface structure having a structure in which any one of the above-described optical filters for display is laminated on the front surface of the display panel or the frontmost layer laminated on the front of the panel. This is proposed (claim 9).
Above all, the frontmost layer laminated on the panel front surface of the display panel has a mesh part composed of a line part connected to the peripheral part on the inner part leaving the peripheral part of the layer made of a conductive material. The display surface structure is composed of an electromagnetic wave shielding film or sheet, and the display optical filter is laminated on the front surface of the mesh part, and the peripheral part of the electromagnetic wave shielding film is exposed on the front surface side. Preferred (claim 10).

Since the optical filter for display and the display surface structure of the present invention are provided with a predetermined transparent gel adhesive layer, they can be directly attached to the front side of the display panel without separately applying an adhesive or adhesive, Moreover, since the transparent gel adhesive layer has excellent buffering properties, adhesiveness, peelability, flexibility, etc., it has excellent impact resistance to protect the display panel from external impact, easily without requiring high pressure and high temperature Even if the surface to be bonded to which the optical filter is bonded, such as the mesh surface of the electromagnetic wave shielding film, is an uneven surface, for example, without generating bubbles by laminating or the like usually performed by laminating films Can be laminated flat and clean. Moreover, it can be easily peeled off.
In particular, in the PDP panel, the surface temperature during light emission is about 60 to about 90 ° C., and a temperature difference is generated between the room temperature and the panel surface when used in a general home environment. For this reason, the pressure-sensitive adhesive that directly attaches the filter to the PDP panel is required to have heat resistance and heat cycle durability. However, the pressure-sensitive adhesive that has been used in the past is a panel under such severe conditions. In contrast to the fact that there were hardly any conflicting properties such as adhesiveness to the panel and peelability from the panel, the transparent gel pressure-sensitive adhesive of the present invention can satisfy both such conflicting properties.

Note that the upper and lower limits of the numerical range in the present invention are within the equivalent range of the present invention as long as they have the same operational effects as those within the numerical range, even if they are outside the numerical range specified by the present invention. included.
Further, in the present invention, “transparent” means colorless and transparent, colored and translucent.

Hereinafter, an example of an embodiment configured for PDP will be described with reference to the drawings. However, the scope of the present invention is not limited to the embodiment described below.

  The display optical filter 1 can be used without separately applying an adhesive or an adhesive to the panel front surface 100a of the display panel 100 having a drive control circuit on the back side or the front surface 101a of the layer 101 laminated on the panel front surface 100a. An optical filter that can be directly bonded, including a filter body 10 composed of a plurality of layers having various functions, and the back surface of the filter body 10 (the surface on the PDP side, in other words, the surface on the bonding side), The transparent gel adhesive layer 2 can be laminated on the back surface 11a of the layer 11 on the most back surface side (PDP side, in other words, the bonding side) of the filter body 10 (see FIGS. 1 to 7).

(Filter body)
The laminated structure of the filter body 10 is not particularly limited. For example, any one of the visible light low reflection layer 4, the near-infrared cut layer 5, the image quality correction layer 6, the electromagnetic wave shielding layer 7, and the moisture permeation prevention layer 8 is provided on one side or both sides of the transparent substrate 3 made of a transparent film or sheet. Such a layer or a plurality of layers composed of a combination of two or more selected from these layers can be laminated (a specific laminated structure will be described later).
Here, even if the surface on which the layer 2 is laminated is an uneven surface provided with unevenness, the transparent gel adhesive layer 2 is adapted to the unevenness and absorbs the unevenness, and is laminated flat without generating bubbles. Since the back surface of the filter body 10, in other words, the back surface 11 a of the layer 11 on the most back surface side of the filter body 10, that is, the laminated surface 11 a of the filter body 10 on which the transparent gel adhesive layer 2 is laminated, In the case of a surface having irregularities, for example, as shown in FIG. 11, the effect of the present invention is further exhibited in the case of a surface that is an irregular pattern surface composed of linear portions 12 having a convex height of 1 μm to 1 mm ( Claim 4). In this case, the line part means a protruding line part that is elongated like a line when seen in a plan view. Specifically, it is a mesh portion 23 composed of a mesh-like linear portion, as in a mesh portion 23 of the electromagnetic wave shielding layer 7 described later (Claim 6) (see FIGS. 3, 4, and 8 to 10). ).

  More specifically, for example, as shown in FIG. 1, a near-infrared cut layer 5, an image quality correction layer 6, and a visible light low reflection layer 4 are sequentially laminated on the front surface side of the transparent substrate 3. The filter main body 10 is configured such that the moisture permeation preventive layer 8 is laminated on the back surface of the filter, and the transparent gel adhesive layer 2 is laminated on the back surface of the filter main body 10, that is, the back surface of the moisture permeation preventive layer 8. The filter 1 can be configured.

  Further, as shown in FIG. 2, the visible light low reflection layer 4 is laminated on the front surface of the transparent substrate 3, while the moisture permeation preventing layer 8, the near infrared cut layer 5, and the image quality correction layer 6 are formed on the back surface of the transparent substrate 3. Are sequentially laminated on the back surface side, and the filter body 10 is configured, and the transparent gel adhesive layer 2 is laminated on the back surface of the filter body 10, that is, the back surface of the image quality correction layer 6 to configure the optical filter 1 for display. be able to.

Further, as shown in FIG. 3, a near-infrared cut layer 5, an image quality correction layer 6, and a visible light low reflection layer 4 are sequentially laminated on the front surface side of the transparent substrate 3, while the transparent substrate 3 has a transparent surface on the back surface. The filter main body 10 is configured by sequentially laminating the moisture prevention layer 8 and the electromagnetic wave shielding layer 7 on the back side,
The end face of the filter body 10, that is, the laminated end face formed by laminating each layer is covered with the conductive adhesive tape 9, and one side edge of the conductive adhesive tape 9 is covered with the back surface (conductive) from the edge of the electromagnetic wave shielding layer 7. The other side edge of the conductive adhesive tape 9 is folded from the edge of the visible light low reflection layer 4 into the front surface, and the other side edge of the conductive adhesive tape 9 is connected to the electromagnetic wave shielding layer 7. The optical filter 1 for display can be configured by laminating the transparent gel adhesive layer 2 on the back surface of the electromagnetic wave shielding layer 7 with the edge interposed.

Further, as shown in FIG. 4, the visible light low reflection layer 4 is laminated on the front surface of the transparent substrate 3 on the front surface of the transparent substrate 3, while the moisture permeation preventing layer 8 and the near infrared cut layer are formed on the back surface of the transparent substrate 3. 5, the filter body 10 is configured by sequentially laminating the image quality correction layer 6 and the electromagnetic wave shielding layer 7 on the back surface side,
The end face of the filter body 10, that is, the laminated end face formed by laminating each layer is covered with the conductive adhesive tape 9, and one side edge of the conductive adhesive tape 9 is covered with the back surface (conductive) from the edge of the electromagnetic wave shielding layer 7. The other side edge of the conductive adhesive tape 9 is folded from the edge of the visible light low reflection layer 4 into the front surface, and the other side edge of the conductive adhesive tape 9 is connected to the electromagnetic wave shielding layer 7. The optical filter 1 for display can be configured by laminating the transparent gel adhesive layer 2 on the back surface of the electromagnetic wave shielding layer 7 with the edge interposed.

Further, as shown in FIG. 5, on the front surface of the transparent substrate 3, a moisture permeation preventing layer 8, a near infrared cut layer 5, an image quality correcting layer 6, an electromagnetic wave shielding layer 7, a transparent gel adhesive layer 2, and a visible light low reflection layer 4. Are sequentially laminated on the front surface side, and the filter body 10 is configured so that the moisture permeation preventing layer 8 is laminated on the back surface of the transparent substrate 3.
The display-use optical filter 1 can be configured by laminating the transparent gel adhesive layer 2 on the back surface of the filter body 10, that is, the back surface of the moisture permeation preventing layer 8.

Further, as shown in FIG. 6, a moisture permeable prevention layer 8, an electromagnetic wave shielding layer 7, a transparent gel adhesive layer 2, and a visible light low reflection layer 4 are sequentially laminated on the front surface side of the transparent substrate 3, while the transparent substrate 3 3, the filter body 10 is configured so that the moisture permeation preventing layer 8, the near-infrared cut layer 5, and the image quality correction layer 6 are sequentially laminated on the back side,
The display optical filter 1 can be configured by laminating the transparent gel adhesive layer 2 on the back surface of the filter body 10, that is, on the back surface of the image quality correction layer 6.

Further, as shown in FIG. 7, on the front surface of the transparent substrate 3, a moisture permeation preventing layer 8, an electromagnetic wave shielding layer 7, a transparent gel adhesive layer 2, a near infrared cut layer 5, an image quality correction layer 6, and a visible light low reflection layer 4. Are sequentially laminated on the front surface side, and the filter body 10 is configured so that the moisture permeation preventing layer 8 is laminated on the back surface of the transparent substrate 3.
The display-use optical filter 1 can be configured by laminating the transparent gel adhesive layer 2 on the back surface of the filter body 10, that is, the back surface of the moisture permeation preventing layer 8.

(Panel surface)
As described above, the surface to be bonded to which the optical filter for display of the present invention is bonded, in other words, the surface to be bonded to which the transparent gel adhesive layer 2 is bonded is also the panel front surface 100a of the display panel 100 (see FIGS. 3 to 7). ), Or the front surface 101a of the layer 101 laminated on the panel front surface 100a (see FIGS. 1 and 2). However, even if the transparent gel adhesive layer 2 has unevenness, the transparent gel pressure-sensitive adhesive layer 2 has a characteristic that it can flexibly conform to the unevenness and absorb the unevenness, and can be bonded flatly without generating bubbles. When the surface is provided with unevenness, for example, when the surface is an uneven pattern surface composed of a linear portion having a convex height of 1 μm to 1 mm, the effect of the present invention can be further enjoyed (Claim 5). Specifically, for example, as shown in FIGS. 1 and 2, the front surface 101a of the electromagnetic wave shielding layer 7 (101) is a surface to be adhered, and the electromagnetic wave shielding layer 7 is made of an electromagnetic wave shielding film or sheet as described later. The effect of this invention can be enjoyed much more, when comprised from 20 and making the mesh part 24 into a to-be-adhered surface.

  Next, the function, configuration, formation method, and the like of each layer described above will be described.

(Transparent substrate)
As the transparent substrate 3 of the optical filter for PDP, either glass or transparent resin can be used, but it is preferable to use a transparent resin from the viewpoint of light weight.
The transparent resin is not particularly limited as long as it is substantially transparent and does not significantly absorb and scatter light. Specific examples include polyolefin resins, polyester resins, polycarbonate resins, poly (meth) acrylate resins, polystyrene, polyvinyl chloride, polyvinyl acetate, polyarylate resins, polyethersulfone resins, and the like. Can do. Among these, amorphous polyolefin resins, polyester resins, polycarbonate resins, poly (meth) acrylate resins, polyarylate resins, and polyether sulfone resins are particularly preferable and have excellent impact resistance. In this respect, polycarbonate resin is particularly preferable.
The above resins are blended with known additives such as phenolic and phosphorus antioxidants, halogen and phosphoric acid flame retardants, heat aging inhibitors, ultraviolet absorbers, lubricants, antistatic agents, etc. can do.
The transparent substrate can be molded by a known molding method such as T-die molding, calendar molding, or press molding, or a method in which the resin is dissolved in an organic solvent and cast.
The thickness of the transparent substrate is preferably selected in the range of 10 μm to 5 mm depending on the purpose, but is not particularly limited. From the viewpoint of securing impact resistance and smoothness of the viewing surface, the thickness of about 100 μm to 3 μm is preferable to the thin film.
When the transparent substrate is thin, that is, when a film is used as the transparent substrate, the film may be unstretched or stretched. Further, it may be laminated with another plastic substrate.
The surface of the transparent substrate is subjected to surface treatment by a conventionally known method such as corona discharge treatment, flame treatment, plasma treatment, ultraviolet treatment, glow discharge treatment, roughening treatment, chemical treatment, or a primer coating on one side or both sides. It may be given.

(Near-infrared cut layer)
A near-infrared cut layer is a layer provided with the effect | action which absorbs the light of a near-infrared part (wavelength 700nm-1200nm).
The near-infrared cut layer only needs to satisfy the characteristics to be provided, and can be formed, for example, by coating with a near-infrared absorbent coating solution.
As the near-infrared absorbing coating solution, a near-infrared absorber is dispersed or dissolved in an organic solvent and a binder resin is added, or a near-infrared absorber is a monofunctional or polyfunctional agent such as polyurethane acrylate or epoxy acrylate. Hard coat agent containing functional acrylate, photopolymerization initiator and organic solvent (including isocyanate, polyurethane, polyester, polyethyleneimine, polybutadiene or alkyl titanate), anchor coat agent, adhesive, etc. Or what was added to the mixed component etc. which consist of these 2 or more types of combinations can be illustrated.
Near-infrared absorbers include organic substances such as nitroso compounds and their metal complex salts, cyanine compounds, squarylium compounds, thionyl nickel complex compounds, phthalocyanine compounds, naphthalocyanine compounds, triallylmethane compounds, imonium compounds. Compound, diimonium compound, naphthoquinone compound, anthraquinone compound, amino compound, aminium salt compound, or inorganic carbon black, indium tin oxide, antimony tin oxide, periodic table 4A, 5A or 6A The thing which consists of a combination of at least 2 types chosen from an oxide, a carbide | carbonized_material, or a boride etc. can be mentioned. Among these, at least one kind is preferably a near infrared absorber selected from an imonium compound, a diimonium compound, or an aminium salt compound. Among these, it is preferable to use in combination at least one selected from near-infrared absorbers other than imonium compounds, diimonium compounds and aminium salt compounds.
As a method of laminating the near-infrared cut layer, a method of directly coating the near-infrared absorbent coating liquid on the surface to be laminated, and after coating the near-infrared absorbent coating liquid on a transparent film, via an adhesive A method of closely adhering to a surface to be laminated, a method of kneading a near-infrared absorber into a resin constituting the surface to be laminated, a flexible adhesive having a function of mitigating an external impact described later (transparent of the present invention A method of kneading a near-infrared absorber into a gel pressure-sensitive adhesive) and other methods can be employed.

(Image quality correction layer)
The image quality correction layer balances the wavelength distribution of transmitted white light by adjusting the light transmittance of blue, green, and red by cutting the neon light emission associated with the light emission of the PDP panel. It is a layer that has a function to make the screen viewable.
The image quality correction layer can be formed, for example, by coating a colorant coating solution containing a colorant whose type and amount are selected so as to satisfy the above functions.
The colorant coating solution is one in which each colorant is dispersed or dissolved in an organic solvent and a binder resin is added, or the colorant is started to photopolymerize with a monofunctional or polyfunctional acrylate such as polyurethane acrylate or epoxy acrylate. Hard coat agent (including isocyanate, polyurethane, polyester, polyethyleneimine, polybutadiene, alkyl titanate, etc.), anchor coat agent, adhesive, etc. What was added to the mixed component etc. which consist of a combination of more than a kind can be illustrated.
The method of laminating the image quality correction layer is a method of directly coating the colored coating liquid on the surface to be laminated, a method of coating the colored coating liquid on a transparent film, and then sticking it to the layered surface via an adhesive, A method in which a colorant is kneaded into a resin constituting the surface to be laminated, and a colorant is kneaded into a flexible pressure-sensitive adhesive (the transparent gel pressure-sensitive adhesive of the present invention) having a function to alleviate external impact described later. Methods and other methods can be employed.

(Visible light low reflection layer)
The visible light low reflection layer is a layer having a function of suppressing light reflection on the surface and improving the transmittance of the filter.
As a method of laminating a visible light low reflection layer, an inorganic substance such as a metal oxide, fluoride, silicide, boride, carbide, nitride, sulfide is deposited on one surface of a transparent filter by vacuum deposition, A method of laminating a single layer or a multilayer by a sputtering method, an ion plating method, an ion beam assist method or the like, a method of laminating a resin having a different refractive index such as an acrylic resin or a fluorine resin, or an antireflection treatment. Examples of the method include a method of forming a so-called low-reflective layer that has been subjected to adhesive processing on the back surface of the film subjected to.
As the resin sheet or film serving as the base of the visible light low reflection layer, the resin exemplified as the filter substrate can be appropriately used.

(Electromagnetic wave shielding layer)
The electromagnetic wave shielding layer is a layer having a function of substantially cutting electromagnetic waves radiated from the display screen when the PDP panel is driven to emit light.
As the electromagnetic wave shielding layer, it is only necessary to have the characteristics to be possessed by the electromagnetic wave shielding layer, and the method for laminating or manufacturing the conductive fiber mesh is not particularly limited. Examples thereof include a method of depositing a conductive substance such as an oxide, a method of laminating a metal thin film on a transparent plastic film surface, and etching the laminated surface to form a mesh portion.

  Among these, from the viewpoint of both electromagnetic shielding properties and light transmittance, a metal thin film 22 is laminated on the surface of a transparent plastic film or sheet 21, as shown in FIGS. It is preferable to laminate an electromagnetic wave shielding film or sheet 20 having a mesh portion 24 formed by etching the surface and having a plurality of linear portions 23 vertically and horizontally intersecting.

  In such a mesh type electromagnetic wave shielding film or sheet 20, the transparent plastic film or sheet 21 is preferably transparent and easily adhesive, and the resin exemplified as the transparent substrate as the filter substrate is preferably used. it can. Of these, polyethylene terephthalate (PET) is preferable.

The metal thin film 22 can be formed of a metal such as copper, aluminum, nickel, or a conductive material such as a metal oxide. The thickness of the metal thin film 22 (in this case, the same as the convex height of the line portion 23) varies depending on the required physical properties and applications, but is preferably 10 nm to 100 μm, particularly 3 μm to 18 μm, and particularly preferably 7 μm to 12 μm.
The mesh portion 24 forms a mesh-like geometric figure, and the line width constituting the geometric figure is preferably 25 μm or less, particularly preferably 5 μm to 15 μm, the line interval is preferably 250 μm or more, particularly preferably 260 μm to 300 μm, and the line thickness. Is preferably 18 μm or less, particularly 3 μm to 18 μm, more preferably 5 μm to 16 μm, and particularly preferably 7 μm to 12 μm. Further, the following 1 [Omega / cm ² area resistivity (also referred to as 1 [Omega / sq), in particular 0.1 [Omega / cm ² or less, preferably especially 0.01~0.1Ω / cm ² preferably. Note that when a mesh type electromagnetic wave shielding film or sheet is used, an interference fringe of light may be generated. Therefore, it is desirable to appropriately set an optimal mesh bias angle for various PDP panels.
As a method for forming the mesh portion 24, for example, a method of transferring or depositing a conductive material such as a metal or a metal oxide on a transparent plastic film or sheet 21 can be employed. However, it is not limited to these.
As a transfer method, for example, transfer can be performed via a UV curable (ultraviolet curable) acrylic adhesive or the like.
On the other hand, when using a deposition type electromagnetic wave shielding film or sheet 20 formed by depositing a conductive material such as metal or metal oxide, the conductive material deposited on the transparent resin film or sheet 21 is released from the PDP. Vapor deposition is performed for the purpose of shielding electromagnetic waves, but any material may be used as long as it transmits 70% or more of a visible light region of 400 to 700 nm and has a surface resistivity of 5 Ω / cm ² or less. Preferably, a metal oxide such as tin oxide, indium tin oxide (hereinafter referred to as ITO), antimony tin oxide (hereinafter referred to as ATO), or a laminate in which metal oxide and metal are alternately stacked has a surface resistivity. Since it can be lowered, it is more preferable. Examples of the metal oxide include tin oxide, ITO, and ATO. As the metal, silver or a silver-palladium alloy is generally used, and usually 3 to 11 layers are laminated starting from the metal oxide layer. Those are preferred. As a vapor deposition method, a normal method such as a vacuum vapor deposition method, a sputtering method, an ion plating method, a chemical vapor deposition method, or a plasma chemical vapor deposition method can be employed. The degree of vacuum at the time of vapor deposition is preferably 1 × 10 ⁻⁴ Torr or less in the case of vacuum vapor deposition and 1 × 10 ⁻² Torr or less in the sputtering method. When the sputtering method is used, the sputtering gas is argon gas or oxygen / argon mixed gas. Furthermore, when vapor-depositing, it is preferable to heat-treat the transparent resin film or sheet 21 in order to reduce resistance. The condition varies depending on the material of the transparent resin film or sheet 21 to be used, but it is preferable that the temperature is 5 to 11 ° C. lower than the thermal deformation start temperature.

In order to function as an electromagnetic wave shielding layer, it is necessary to ground the electricity accumulated in the electromagnetic wave shielding layer, and it is necessary to expose a portion to which the earth is connected to the front side (that is, the viewing surface side) as an earth electrode. . Therefore, when the electromagnetic wave shielding layer is laminated on the panel front surface 100a of the display panel 100 or when the electromagnetic wave shielding layer is laminated in the filter body 10, the conductivity as the ground electrode is, for example, as shown in FIGS. It is possible to employ a configuration in which one end of the tape is connected to the electromagnetic shield film or the conductive surface (the back surface in the figure) of the sheet 20 and the other end is disposed on the foreground so that the ground electrode is exposed on the front surface side. However, the structure becomes complicated.
Therefore, a mesh portion 24 is formed on the inner portion 20B of the peripheral portion 20A surrounding the film or sheet made of a conductive material, in which a plurality of linear portions 23 connected to the peripheral portion 20A are arranged in a mesh shape. An electromagnetic wave shielding layer is formed from the electromagnetic wave shielding film or sheet 20 formed as shown in FIGS. 1, 2, 5, 6, and 7, with the transparent gel adhesive layer 2 interposed in front of the mesh portion 24. The display optical filter 1 is laminated, and the peripheral surface 20A is exposed to the front side to constitute the display surface structure. If comprised in this way, since earth | ground can be connected to the peripheral part 20A from the front side and a display surface structure can be simplified more, manufacturing cost can be suppressed further.

(Moisture permeation prevention layer)
The moisture permeation preventive layer is a layer having a function of being excellent in barrier properties that substantially cut off the passage of water vapor and the like and also having excellent transparency.
The moisture permeation preventive layer is not particularly limited as long as it has the characteristics that the moisture permeation preventive layer should have. For example, a transparent barrier film in which an aluminum oxide film is provided on at least one surface of a transparent plastic film can be employed. At this time, the aluminum oxide film can be formed by appropriately controlling the conditions in a vacuum deposition method, a sputtering method, an ion beam deposition method, or the like. The vacuum deposition method is preferred because it is the easiest and the productivity is good. In this vacuum evaporation method, it can manufacture by introduce | transducing oxygen gas on specific conditions at the time of vacuum evaporation. In general, when the oxygen gas supply rate is less than 2.6 (× 10 ⁻⁴ ) in relation to the oxygen gas supply rate and the deposition rate, the total light transmittance tends to decrease and the transparency tends to deteriorate. Yes, if the oxygen gas supply rate is more than 3.7 (× 10 ^-4 ) in relation to the oxygen gas supply rate and the deposition rate, the transparency is good, but the oxygen permeability and water vapor permeability increase. The barrier property tends to be worse.
The base film for the moisture permeation preventing layer includes polyester film, polypropylene film, polyethylene film, polycarbonate film, polyamide film, polyacetal film, polyimide film, polyvinylidene chloride film, polyethersulfone film, polyacrylate film, polymethacrylate Acid ester films, polyvinyl alcohol films, polystyrene films and the like can be used. The thickness of the transparent plastic film is not particularly limited, but is preferably about 2 to 250 μm, particularly about 9 to 125 μm from the viewpoint of plasticity, thermal characteristics, mechanical characteristics, and the like.
Note that when oxygen gas is introduced, plasma may be generated by discharging the oxygen gas by direct current, alternating current, high frequency, microwave, or the like. When plasma is generated by discharge, the oxygen gas is more activated and the reaction efficiency between aluminum and oxygen is improved, so that a denser and better-quality aluminum oxide film can be easily formed. An effect can be obtained. In addition, when making it discharge at the time of introduction | transduction of oxygen gas, introduction | transduction may be introduction of only oxygen gas, but argon gas may be mixed and introduced in oxygen gas a little. When argon gas is mixed, a stronger plasma is generated and oxygen gas is more activated than when only oxygen gas is introduced, so that a denser and better quality aluminum oxide film is easily formed and thinner. A desired effect can be obtained by the deposited film thickness. However, when the ratio of argon gas increases too much, the arrival of the aluminum oxide film becomes incomplete and the degree of vacuum is lowered. Therefore, the mixing ratio of oxygen gas and argon gas is 95: 5 to 70 by volume. : 30 is preferable.
Even if the aluminum oxide film is a thin film having a thickness of 30 to 100 mm measured by fluorescent X-ray, a product excellent in oxygen barrier property, water vapor barrier property and transparency can be obtained. When the thickness of the aluminum oxide film is less than 30 mm, the barrier property is lowered, and when it is thicker than 100 mm, the productivity is lowered. Therefore, the thickness of the aluminum oxide film is preferably in the range of 30 to 100 mm. An aluminum film is preferable because a stable and excellent oxygen barrier property, water vapor barrier property, and transparency can be obtained.

  In the above, the structure, function, and forming method of each of the transparent substrate, the low visible light reflection layer, the near-infrared cut layer, the image quality correction layer, the electromagnetic wave shielding layer, and the moisture permeation prevention layer have been described. It can be arbitrarily formed as long as it satisfies the characteristics that each layer should have. Further, the stacking order is arbitrary, and it is also arbitrary to stack layers having further functions.

(Transparent gel adhesive layer)
Next, the transparent gel adhesive layer will be described.

The transparent gel pressure-sensitive adhesive layer can be formed from a transparent gel-like transparent gel pressure-sensitive adhesive obtained by swelling a three-dimensional crosslinked polymer.
“Gel” means that a three-dimensional cross-linked polymer is swollen in a liquid (Polymer Dictionary, published by Maruzen, Hei 6.9.20), or a colloidal solution loses its fluidity and has some elasticity. It is a substance that has both the properties of a polymer solution and the properties of a rubber elastic body.

The transparent gel pressure-sensitive adhesive used in the present invention is a transparent gel in which a three-dimensional cross-linked polymer is swollen with a liquid containing a plasticizer and inorganic fine particles, and has a desired range of holding power, buffer power, and pressure-sensitive adhesive force. It needs to be a thing.

At this time, as a main factor for adjusting the holding power, buffering power and adhesive strength of the transparent gel pressure-sensitive adhesive, the type of resin constituting the three-dimensional crosslinked polymer (this uncrosslinked resin is referred to as “base polymer”). (Including differences in molecular weight), crosslinking density, type and content of plasticizer, shape and content of inorganic fine particles, and the like.
Holding power, buffering power and adhesive strength are mutually opposite physical properties, and each physical property cannot be controlled independently. However, the holding power mainly includes gel cross-linking density and inorganic fine particles (especially its particle size and blending amount). The crosslinking density can be controlled mainly by the crosslinking method and its conditions. The buffering force is affected by the degree of swelling of the gel, and the degree of swelling can be adjusted mainly by the type and content of the plasticizer. The adhesive strength can be adjusted mainly by the melt viscosity and glass transition temperature (Tg) of the base polymer, and the melt viscosity of the base polymer can be mainly adjusted by the molecular weight of the polymer.

(Three-dimensional cross-linked polymer)
The three-dimensional crosslinked polymer constituting the skeleton (network) of the transparent gel pressure-sensitive adhesive can be formed by crosslinking the base polymer.

Examples of the base polymer include (meth) acrylic acid ester copolymer polymers and urethane resins, and (meth) acrylic acid ester copolymer polymers are particularly preferable.
(Meth) acrylate used for forming a (meth) acrylate copolymer polymer, that is, as an alkyl acrylate or alkyl methacrylate component, an alkyl group is n-octyl, isooctyl, 2-ethylhexyl, n-butyl, It is preferable to use one of alkyl acrylate or alkyl methacrylate which is any one of isobutyl, methyl, ethyl and isopropyl, or a mixture of two or more selected from these.
As other components, an acrylate or methacrylate having an organic functional group such as a carboxyl group, a hydroxyl group, or a glycidyl group may be copolymerized. Specifically, a monomer component obtained by appropriately and selectively combining the alkyl (meth) acrylate component and the (meth) acrylate component having an organic functional group as a starting material is subjected to heat polymerization to form a (meth) acrylate ester copolymer. A polymer polymer can be obtained.

The base polymer has a glass transition temperature (Tg) of −20 ° C. or less, preferably −60 ° C. to −40 ° C., and a melt viscosity at 130 ° C. of 50,000 mPa · s or more, preferably 200,000 to 700,000 mPa. · S, particularly preferably 200,000 to 500,000 mPa · s resin is used.
If the Tg and melt viscosity of the base polymer are within the above ranges, at least the adhesive strength of the transparent gel adhesive can be adjusted to a desired range. When the melt viscosity is less than 50,000 mPa · s, it is difficult to obtain shape stability during sheet molding, and it is difficult to obtain sufficient flexibility for the crosslinked sheet. On the other hand, if Tg is higher than −20 ° C., the low temperature durability of the laminate is reduced.
When Tg is −60 to −40 ° C. and the melt viscosity is 200,000 to 700,000 (mPa · s), flexibility and durability can be further improved.

The glass transition temperature (Tg) and melt viscosity of the base polymer can be measured using a B-type viscometer (for example, a viscoelasticity measuring device dynamic analyzer RDA-II manufactured by Rheometrics). At that time, the melt viscosity may be measured by reading the viscosity (ηγ) value measured at a parallel plate 25 mmφ, strain 2%, 130 ° C., 0.02 Hz, and Tg was measured at a parallel plate 25 mmφ, strain 2%, frequency 1 Hz. What is necessary is just to read the temperature which shows the maximum value of Tanδ at the time.
The blending amount of the base polymer depends on the kind of polymer, but for example, it is preferably 10 to 90% by weight, particularly 30 to 70% by weight in the case of a (meth) acrylic acid ester copolymer.

The type of the crosslinking method and the crosslinking agent is not particularly limited. However, since the crosslinking density that affects the holding power varies depending on the crosslinking method and its conditions, the crosslinking method and the crosslinking method are adjusted so that the holding force is finally adjusted to a desired range. It is necessary to select the conditions, that is, the type and amount of the crosslinking agent and the crosslinking conditions.
As a preferred crosslinking method, a method of blending a crosslinking monomer and a photoinitiator into the base polymer and forming a three-dimensional crosslinked polymer by photocrosslinking can be mentioned. Since the crosslinking density can be adjusted by the blending amount of the crosslinking monomer and the impregnation amount of the plasticizer can be adjusted, the flexibility of the transparent gel pressure-sensitive adhesive can be adjusted within a preferable range.
Specifically, a base polymer (uncrosslinked), a crosslinking monomer, a photoinitiator and inorganic fine particles are mixed and dispersed, and then photocrosslinked (ultraviolet irradiation) to form a gel pressure-sensitive adhesive sheet by three-dimensional crosslinking. Is preferred.

As a combination of a preferable base polymer, a crosslinking monomer and a photoinitiator, a (meth) acrylic ester copolymer containing an α or β unsaturated carboxylic acid and an organic functional group which reacts with the unsaturated carboxylic acid are contained. A combination of a (meth) acrylate monomer and a photoinitiator can be mentioned.
As the (meth) acrylic acid ester-based copolymer containing α, β unsaturated carboxylic acid, for example, at least one or more from iso-octyl acrylate, n-octyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, and the like, The thing which copolymerized acrylic acid can be mentioned.
On the other hand, the organic functional group-containing (meth) acrylate monomer reacts with the unsaturated carboxylic acid such as glycidyl group-containing (meth) acrylate monomer, hydroxy group-containing (meth) acrylate monomer, isocyanate group-containing (meth) acrylate monomer, etc. The thing which has a functional group can be mentioned. The content is 0.01 to 20 parts by weight (0.01 to 2.3% by weight in the gel), particularly 3 to 15 parts by weight (2 to 5% by weight in the gel) with respect to 100 parts by weight of the base polymer. Is preferable.

As a photoinitiator, a thing with little coloring property and odor property is preferable. For example, it is preferable to use a mixed component composed of either benzophenone or hydroxy-cyclohexyl-phenyl ketone, or a combination of two or more of these.
What is necessary is just to adjust the addition amount of a photoinitiator suitably according to the kind of photoinitiator, for example, when using benzophenone, it is 0.05-10 weight part with respect to 100 weight part of base polymers (0.04-in gel). 1.2% by weight), particularly 1 to 7.5 parts by weight (0.7 to 2.5% by weight in the gel).

(Plasticizer)
The plasticizer can adjust the degree of swelling of the transparent gel adhesive by adjusting the type and amount thereof, and as a result, the buffering force can be adjusted. From this viewpoint, it is preferable to contain 10 to 70% by weight of a liquid having a freezing point of −20 ° C. or less (11 to 600 parts by weight with respect to 100 parts by weight of the base polymer) in the gel. If the plasticizer content is less than 10% by weight, it is difficult to obtain impact resistance, and conversely if it exceeds 70% by weight, it becomes difficult to obtain adhesiveness. Considering the use as an adhesive for PDP panel in particular, the gel containing 30 to 50% by weight (45 to 150 parts by weight with respect to 100 parts by weight of the base polymer) having a freezing point of −80 to −40 ° C. preferable.

The plasticizer is one of adipic acid ester, phthalic acid ester, phosphoric acid ester, trimellitic acid ester, citrate ester, epoxy, polyester plasticizer, or a combination of two or more of these. Mixed components can be used, and those compatible with the (meth) acrylic acid ester copolymer are preferred. In the case of ultraviolet photocrosslinking, it is preferable to use a plasticizer that does not absorb ultraviolet rays.

(Inorganic fine particles)
If the three-dimensional cross-linked polymer is merely swollen with a liquid plasticizer, the viscosity of the gel pressure-sensitive adhesive before cross-linking (that is, the sol stage) is too low to form a sheet. Further, no elongation is obtained after crosslinking, resulting in a soft but brittle sheet. Therefore, as a result of intensive studies and studies by the present inventors, the gel adhesive can be appropriately thickened without compromising transparency by blending a predetermined amount of inorganic fine particles having a predetermined particle diameter, and with a desired holding power. It has been found that an adhesive strength can be obtained, a sheet can be easily formed, and a flexible gel having viscoelasticity can be prepared.

The inorganic fine particles have a primary average particle size of 200 nm or less, preferably 0.1 to 50 nm, particularly preferably 1 to 20 nm, and the inorganic fine particles having such a particle size are preferably 1 to 15% by weight ( 1 to 130 parts by weight with respect to 100 parts by weight of the base polymer), particularly 2 to 10% by weight (2 to 10 parts by weight with respect to 100 parts by weight of the base polymer), and particularly preferably 3 to 5% by weight.
The inorganic fine particles have the effect of increasing the viscosity of the gel pressure-sensitive adhesive as described above to facilitate sheet molding and imparting elasticity to the crosslinked gel pressure-sensitive adhesive or gel pressure-sensitive adhesive sheet. In addition, it is also important in order not to inhibit transparency and ultraviolet crosslinkability.
In order to satisfy the molding processability, the elastic strength and holding power after crosslinking, and the transparency, it is preferable to contain 2 to 10% by weight of inorganic fine particles having a particle size of 100 nm or less in the gel.

Examples of the inorganic fine particles include alumina (Al ₂ O ₃ ), zinc oxide (ZnO), metal oxides such as indium-tin oxide (ITO), silicate compounds such as silica, diatomaceous earth, and aluminum (Al). Further, fine particles of metal such as silver (Ag) can be used, and it is preferable to select appropriately in consideration of dispersibility.
Moreover, materials other than those listed above can be blended within a range that does not impair transparency.

(Transparent gel adhesive)
The transparent gel pressure-sensitive adhesive used in the present invention needs to adjust the holding force, the pressure-sensitive adhesive force and the buffering force to a desired range. In particular, in a test according to JIS Z0237, the load is 490 mN (50 gf) × 2 hours, the holding force at 40 ° C. is 5 mm or less, particularly 0.5 to 2.0 mm from the viewpoint of the balance between flexibility and durability, It is preferable to adjust to the range of 5 to 1 mm.
Holding force, adhesive force and buffering force are mutually opposite physical properties, but if the holding force is adjusted to the above range in the composition described above, all elements of the holding force, adhesive force and buffering force of the transparent gel will be It can be adjusted within the range required by the invention, and a laminate can be formed by laminating a base material and a surface material without applying a large pressure at room temperature. And can give durability.
The holding power in this case is also an index indicating flexibility and durability, and after backing the sheet with a 38 μm PET film in accordance with JIS Z0237, the area is 20 mm using the SUS plate defined by JIS Z0237. It can be determined by measuring the deviation length after applying a load of 490 mN (50 gf) for 2 hours in a 40 ° C. environment under a condition of × 20 mm, 2 kg roll 1 reciprocation.
In addition, JIS Z0237 stipulates that a load of 1 kgf is applied. However, the transparent gel adhesive of the present invention is softer than a normal adhesive, so that it drops immediately when a load of 1 kgf or 500 gf is applied. The performance cannot be evaluated. Therefore, in the present invention, the holding force is measured by changing the load to 490 mN (50 gf) so that the performance of the transparent gel pressure-sensitive adhesive of the present invention can be legitimately evaluated while conforming to JIS Z0237 as much as possible. did.

  The holding power of the transparent gel pressure-sensitive adhesive can be adjusted mainly by changing the crosslinking density and inorganic fine particles (particle size and blending amount) and the like. In this case, the amount can be adjusted to a desired range by adjusting the amount of the photoinitiator, the integrated light amount (the integrated value of the illumination light amount and the illumination time), and the like.

Since such a transparent gel adhesive has a desired adhesive strength at room temperature, for example, a base material, a transparent gel adhesive, and a surface material are sequentially laminated and bonded at room temperature simply by passing between rubber rolls. be able to. In addition, since it has the desired holding force, it can absorb the difference in behavior of each member even when physical properties such as linear expansion coefficients are different when bonding different types of materials, and warps after lamination. , Peeling and cracking are not generated, transparency can be maintained well, and an excellent buffering effect can be imparted to the laminate.

(Method for forming transparent gel adhesive layer)
The transparent gel pressure-sensitive adhesive layer can be formed by applying a transparent gel pressure-sensitive adhesive in a form (liquid, viscous liquid, etc.) that is easy to apply to the surface to be laminated. It is preferable to form by laminating | stacking the transparent gel adhesive sheet formed by sheet-molding to the provided sheet form.

  Here, as a preferable example of the transparent gel pressure-sensitive adhesive sheet, a sol composition containing a base polymer, a crosslinking monomer, a photoinitiator, a plasticizer, and inorganic fine particles is prepared, and after the sol composition is formed into a sheet, it is photocrosslinked. And a transparent gel pressure-sensitive adhesive sheet obtained by gelling the sol.

More specifically, a sol composition containing a (meth) acrylic acid ester copolymer polymer, a crosslinking monomer, a UV-reactive photoinitiator, a plasticizer and inorganic fine particles is prepared, and this sol composition is made transparent. It is a gel pressure-sensitive adhesive sheet obtained by applying a suitable thickness between release films and forming a sheet, followed by irradiation with ultraviolet rays using a high-pressure mercury lamp through a release film and the like.
In the irradiation with ultraviolet rays, the crosslinking density and the holding power can be adjusted by adjusting the irradiation amount and the irradiation time according to the amount of the monomer and the photoinitiator.
The thickness of the transparent gel pressure-sensitive adhesive sheet is preferably adjusted according to the object to be bonded, the required buffering force, etc., but is generally 0.5 to 2.0 mm, particularly about 0.5 to 1.0 mm. Is preferred.

Such a transparent gel pressure-sensitive adhesive sheet is formed by sandwiching a release sheet or film material to form a laminated sheet. For example, between the objects (for example, between the base material and the surface material) just by overlapping the base material) and then peeling off the other release sheet or film and overlaying the adhesive surface of the transparent gel pressure sensitive adhesive sheet on the object (for example, the surface material). Can be easily laminated to a certain thickness.
Moreover, since the transparent gel pressure-sensitive adhesive sheet has a desired adhesive force at room temperature, for example, a base material, a transparent gel pressure-sensitive adhesive sheet, and a surface material are sequentially stacked between nip rolls (rubber rolls) at room temperature (without heating). It can be pasted only by applying a slight pressure by passing the.
Because it has the desired holding force as described above, it can absorb differences in the behavior of members to be bonded even when different types of materials are bonded, and warpage, peeling, cracking, etc. occur after lamination The transparency can be maintained well, and an excellent buffering effect can be imparted to the laminate.

  If the transparent gel pressure-sensitive adhesive layer made of such a transparent gel pressure-sensitive adhesive and a transparent gel pressure-sensitive adhesive sheet is used as an intermediate layer of the laminate, even if the surface on which the transparent gel pressure-sensitive adhesive layer is laminated or the other surface to be bonded is not smooth, Further, even if the materials to be bonded are different from each other, the difference in behavior and unevenness of each material can be absorbed and bonded.

  The thickness of the transparent gel pressure-sensitive adhesive layer is such that the surface on which the transparent gel pressure-sensitive adhesive layer is laminated (the surface to be adhered or the surface to be laminated) is a concavo-convex pattern surface composed of linear portions having a convex height of 1 μm to 1 mm. The thickness is preferably 3 times or more, particularly 5 times or more the convex height. If formed to this thickness, the unevenness of the uneven surface can be absorbed to finish the surface cleanly and smoothly.

Hereinafter, the configuration of the present invention will be examined in more detail using examples and comparative examples.

  First, the composition and physical properties of the transparent gel pressure-sensitive adhesive were compared in Examples 1 to 4 and Comparative Examples 1 to 4.

(Example 1)
The product name “Irgacure 500” manufactured by Ciba Specialty Chemicals Co., Ltd. as a photoinitiator and the product name “manufactured by Osaka Organic Chemical Co., Ltd.“ Biscoat V260 (1,9-nonanediol diacrylate) ”(0.3 parts by weight) was added to obtain a UV-crosslinking composition.
The composition of the acrylic ester copolymer used was a copolymer of 78.4% by weight of n-butyl acrylate, 19.6% by weight of 2-ethylhexyl acrylate, and 2.0% by weight of acrylic acid. Tg was −40 ° C., and the melt viscosity at 130 ° C. was 250,000 (mPa · s).

Compounding 20% by weight of diisodecyl phthalate (DIDP) as a plasticizer and 2% by weight of the product name “Aerosil 300” manufactured by Nippon Aerosil Co., Ltd. as silica fine particles having a primary average particle diameter of 7 nm, in the above UV crosslinking composition. The mixture was melted and stirred to obtain a sol composition.

The sol composition is hot-melt molded into a 0.5 mm thick sheet sandwiched between 75 μm and 100 μm release PET, and the accumulated light quantity on one side is 4000 mJ through the release PET using a high-pressure mercury lamp. / Cm ² was irradiated from both front and back sides to obtain a transparent gel adhesive sheet.

And the laminated body was produced by the method shown below using the said gel adhesive sheet.
One side of a special polycarbonate (PC) plate (thickness 1 mm, width 300 mm, length 300 mm), the gel adhesive sheet with one release film peeled off, between the nip rolls and the drive rolls so as to contact for the first time After carrying in and sticking at a linear pressure of 1 kgf / cm and a speed of 1 m / min, the remaining release film was peeled off.
Next, the PC plate on which the gel adhesive sheet is affixed face-to-face without contacting a commercially available float glass plate (thickness 3 mm, width 300 mm, length 300 mm) via the gel adhesive sheet. The laminate was obtained by sandwiching the end portion between the nip roll and the driving roll so as to be in contact with the nip roll (linear pressure: 1 kgf / cm, speed: 1 m / min) for the first time.

In addition, the special PC board used for the laminated body used what laminated | stacked the transparent inorganic oxide film previously on commercially available PC, in order to prevent the influence of a water | moisture content and a plasticizer.

(Example 2)
To 100 parts by weight of the acrylate copolymer used in Example 1, 2.0 parts by weight of a photoinitiator “Irgacure 500” and 2.0 parts by weight of a crosslinking monomer “Biscoat V260” were added to form ultraviolet rays. A crosslinked composition was obtained.

To this UV-crosslinking composition, 60% by weight of a plasticizer diisodecyl phthalate (DIDP) and 10% by weight of silica ultrafine particles “Aerosil 50” having a primary average particle size of 30 nm were mixed and stirred to obtain a sol composition. .

The sol composition is hot-melt molded into a 0.5 mm thick sheet sandwiched between 75 μm thick and 100 μm release PET, and the single-side accumulated light quantity of 4000 mJ / cm ² is released using a high-pressure mercury lamp. A transparent gel pressure-sensitive adhesive sheet was obtained by irradiation from the front and back sides through a mold PET.
A laminate was obtained in the same manner as in Example 1 using the transparent gel pressure-sensitive adhesive sheet thus obtained.

(Example 3)
The UV-crosslinking composition obtained in Example 1 was mixed with 20% by weight of a plasticizer diisodecyl phthalate (DIDP) and 2% by weight of “Aerosil 50”, and melted and stirred to obtain a sol composition. A transparent gel adhesive sheet and a laminate were obtained in the same manner.

Example 4
UV crosslinking composition by adding 2.5 parts by weight of photoinitiator “benzophenone” and 4.5 parts by weight of crosslinking monomer “Biscoat V260” to 100 parts by weight of the acrylate copolymer used in Example 1. I got a thing.
The UV crosslinkable composition thus obtained was mixed with 48% by weight of a plasticizer diisodecyl phthalate (DIDP) and 5% by weight of “Aerosil 300”, and melted and stirred to obtain a sol composition, which was transparent in the same manner as in Example 1. A gel pressure-sensitive adhesive sheet and a laminate were obtained.

(Comparative Example 1)
To 100 parts by weight of the acrylate copolymer used in Example 1, 0.3 part by weight of the photoinitiator “Irgacure 500” and 0.05 part by weight of the crosslinking monomer “Biscoat V260” were added to form ultraviolet rays. A crosslinked composition was obtained.

This UV-crosslinking composition is sandwiched between 75 μm thickness and 100 μm release PET and hot melt molded into a 0.5 mm thickness sheet, using a high-pressure mercury lamp to produce a single-side accumulated light amount of 4000 mJ / cm ² . A transparent adhesive sheet was obtained by irradiating the front and back through a release PET.
A laminate was obtained in the same manner as in Example 1 using the transparent adhesive sheet thus obtained.

(Comparative Example 2)
With respect to 100 parts by weight of the acrylate copolymer used in Example 1, 2.0 parts by weight of the photoinitiator “Irgacure 500” and 2.0 parts by weight of the crosslinking monomer “Biscoat V260” were added to perform UV crosslinking. A mold composition was obtained.
A plasticizer diisodecyl phthalate (DIDP) was blended in the ultraviolet crosslinking composition so as to be 30% by weight and melted and stirred to obtain a sol composition.

The sol composition is hot-melt molded into a 0.5 mm thick sheet sandwiched between 75 μm thick and 100 μm release PET, and the single-side accumulated light quantity of 4000 mJ / cm ² is released using a high-pressure mercury lamp. A transparent gel adhesive sheet was obtained by irradiating the front and back through a mold PET.
A laminate was obtained in the same manner as in Example 1 using the transparent gel pressure-sensitive adhesive sheet thus obtained.

(Comparative Example 3)
The UV-crosslinking composition obtained in Example 1 was mixed with 60% by weight of a plasticizer diisodecyl phthalate (DIDP) and 20% by weight of “Aerosil 50”, and melted and stirred to obtain an adhesive.
A transparent pressure-sensitive adhesive sheet and a laminate were obtained using the pressure-sensitive adhesive in the same manner as in Example 1.

(Comparative Example 4)
To the UV-crosslinking composition obtained in Example 2, 60% by weight of a plasticizer diisodecyl phthalate (DIDP) and silica fine particles having a primary average particle diameter of 500 nm, manufactured by Admatech Co., Ltd., trade name “Admafine SO-E2” 10% by weight Were mixed and melt-stirred to obtain a sol composition, and a transparent gel adhesive sheet and a laminate were obtained in the same manner as in Example 1.

(Comparative test)
The following tests were carried out using the laminates obtained in the above-described examples and comparative examples, and the results are shown in Table 1.

(Evaluation of transparency)
Transparency was evaluated by visual appearance. The thing without white turbidity was evaluated as ○, and the one with white turbidity was evaluated as ×.

(Damp heat durability test)
The appearance of the laminate was observed after standing for 1 week in an atmosphere of a temperature of 60 ° C. and a humidity of 90%. Those without white turbidity, no peeling and no foaming were evaluated as ◯, and those not so were evaluated as ×.

(Cooling durability test)
The appearance of the laminate was observed after standing at a temperature of -20 to 80 ° C. (4 cycles / day) for 1 week. No peeling and no foaming were evaluated as “good”, and those not so were evaluated as “poor”.

(Falling ball impact test)
A glass stand (thickness 3 mm × 100 mm square) is placed on a fixed cylindrical metal support (outer diameter 60 mm / inner diameter 50 mm / height 40 mm), as shown in FIG. The laminates obtained in the examples and comparative examples were placed on the upper side of the PC (polycarbonate) side. Then, a steel ball having a weight of 0.1 kgf was freely dropped from a height of 1 m.
The impact value (0.98 J) at this time was evaluated as “◯” when the float glass of the laminate was not broken, and “×” when it was broken.

(Retention force measurement test)
In order to comply with JIS Z0237 as much as possible, the transparent gel pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples were back-coated with a 38 μm PET film, and then adhered with an area of 20 mm × 20 mm using the SUS plate specified in JIS Z0237. It was determined by measuring the deviation length after applying a load of 490 mN (50 gf) for 2 hours in an environment of 40 ° C. by bonding with a 1 kg reciprocating 2 kg roll.

As is clear from the results in Table 1, when the transparent gel pressure-sensitive adhesive sheet of the example is used, an impact-absorbing laminate that can be laminated at room temperature and is satisfactory in appearance can be obtained. In addition, it was found that the gel pressure-sensitive adhesive sheet in which the ultrafine particle silica is outside the scope of the present invention cannot satisfy all the observation items.

  Next, with respect to the structure of the optical filter for display, Examples 5 to 11 and Comparative Examples 5 to 8 were compared and examined.

(Example 5)
Transparent adhesive sheet (product name: CS, manufactured by Nitto Denko Corporation) with one side of a polycarbonate sheet (product name: Stella S300, manufactured by Mitsubishi Plastics Co., Ltd., 1 mm thick) sandwiched between both sides with a release PET (polyethylene terephthalate) film -9611 ", 25 μm thick) while peeling the template PET film on the light release side, after laminating with a laminator at a linear pressure of 9.6 kgf / cm and room temperature, release PET on the remaining surface of the transparent adhesive sheet While peeling, a near-infrared cut film (Mitsubishi Chemical Co., Ltd.) was laminated with a laminator in the same manner as above, and an image quality correction film (Mitsubishi Chemical Co., Ltd.) and an antireflection film (Nippon Yushi Co., Ltd. “Realak 8201UV”) were sequentially laminated in the same manner. Next, on the back surface of the polycarbonate sheet, a silica-deposited high barrier film (“Fine Barrier” manufactured by Reiko Co., Ltd.) was laminated with a laminator in the same manner as described above, and then a transparent gel adhesive sheet (“Clear Fit” manufactured by Mitsubishi Plastics, An optical filter for PDP was obtained by laminating a thickness 0.5 mm) with a laminator at a linear pressure of 3.2 kgf / cm or less and room temperature.
Next, a mesh type electromagnetic wave shield sheet (manufactured by Nippon Filcon Co., Ltd., without mesh surface smoothing, with back surface adhesion) laminated on the front surface (display surface) of the PDP panel is applied with a line pressure of 3 on the front surface of the mesh portion. Bonding was performed with a laminator at room temperature of 2 kgf / cm or less (see FIG. 1).

The near-infrared cut film used was one in which a near-infrared absorbing coating film (thickness 3 μm) was laminated on both sides of a 50 μm-thick PET film and a 25 μm adhesive layer was formed on the front surface.
The image quality correction film is a film obtained by sequentially laminating a toning coating film (thickness 3 μm) having a Ne light emission cut function and a color adjustment function and a 25 μm adhesive layer on the front surface of a 50 μm thick PET film. used.
The antireflective film is made of a TAC (triacetyl cellulose) 80 μm thick substrate, and a hard coat layer (thickness 2 μm) and a high refractive index layer containing inorganic fine particles (2 μm thick) on the front surface of this substrate ( 0.1 μm thick), a low refractive index layer (thickness 0.1 μm) containing a fluorine-based material, and a protective film (thickness 40 μm) are sequentially laminated, and a UV-absorbing adhesive layer (thickness) on the back surface of the substrate 25 μm) is used. This antireflection film has a minimum reflectance (5 °, −5 ° regular reflectance) of 0.3%, a visibility correction value of 0.8%, a total light transmittance (JIS K7361) of 95.1%, and an ultraviolet ray. The transmittance (350 nm) was 0%, and the haze value (JIS K7105) was 0.3%.
As the silica-deposited high barrier film, a film obtained by laminating a 20 μm adhesive layer on the front surface of a 25 μm thick PET film and laminating an alumina deposited layer and a topcoat layer on the back surface of the PET film was used.

  In addition, the mesh type electromagnetic wave shielding sheet is formed by forming a 9 μm thick copper thin film on one side of a 125 μm thick PET sheet, and etching the inner part leaving a 10 mm wide peripheral part. An electromagnetic wave shielding sheet provided with a mesh portion in which a plurality of 9 μm linear portions intersected in a mesh pattern with a line interval of 280 μm was used.

Further, the transparent gel pressure-sensitive adhesive sheet (“Clear Fit” manufactured by Mitsubishi Plastics, Inc.) is an acrylic acid ester copolymer (n-butyl acrylate 78.4% by weight, 2-ethylhexyl acrylate 19.6% by weight, acrylic acid 2. 0% by weight copolymerized, 100 g by weight of Tg of −40 ° C. and 130 ° C. melt viscosity of 250,000 (mPa · s) base polymer), photoinitiator (Ciba Specialty Chemicals) Trade name “benzophenone”) 2.3 parts by weight (1.0% by weight) and crosslinking monomer (trade name “Biscoat V260” (1,9-nonanediol diacrylate) manufactured by Osaka Organic Chemical Co., Ltd.) And 100 parts by weight (48% by weight) of diisodecyl phthalate (DIDP) as a plasticizer Silica ultrafine particles having a primary average particle size of 7 nm (trade name “Aerosil 300”, manufactured by Nippon Aerosil Co., Ltd.) 12 parts by weight (5% by weight) were blended and melt-stirred to obtain a sol composition. This sol composition Is melt-molded into a sheet of 0.5 mm thickness sandwiched between 75 μm and 100 μm release PET, and a single-sided integrated light amount of 4000 mJ / cm ² is placed on both sides through the release PET using a high-pressure mercury lamp. It is a transparent gel pressure-sensitive adhesive sheet obtained by irradiation and solification.

(Example 6)
An antireflection film is bonded to the front surface of the polycarbonate sheet with a laminator at a linear pressure of 9.6 kgf / cm, and a silica-deposited high barrier film, a near-infrared cut film, and an image quality correction film are sequentially applied to the back surface of the polycarbonate sheet on the back surface side. Bonding was performed using the same laminator, and further, a transparent gel adhesive sheet was bonded to the back surface of the image quality correction film using a laminator having a linear pressure of 3.2 kgf / cm or less at room temperature to obtain an optical filter for PDP.
Next, a mesh type electromagnetic wave shield sheet (manufactured by Nippon Filcon Co., Ltd., without mesh surface smoothing, with back surface adhesion) laminated on the front surface (display surface) of the PDP panel is applied with a line pressure of 3 on the front surface of the mesh portion. Bonding was performed with a laminator at room temperature of 2 kgf / cm or less (see FIG. 2).
In addition, the same thing as Example 5 was used for the polycarbonate sheet, the antireflection film, the silica vapor deposition high barrier film, the near-infrared cut film, the image quality correction film, the transparent gel adhesive sheet, and the mesh type electromagnetic wave shield sheet.

(Example 7)
A near-infrared cut film, an image quality correction film, and an anti-reflection film are laminated on the front side of the polycarbonate sheet in order with a laminator at a linear pressure of 9.6 kgf / cm, and a silica-deposited high barrier film and mesh are placed on the back side of the polycarbonate sheet. A filter body was configured by laminating type electromagnetic shielding films in order on the back side in the same manner as described above using a laminator.
Next, a copper foil tape with a conductive adhesive (25 mm in width) is attached to the four sides around the front surface of the antireflection film for a width of 10 mm from the edge, and the laminated end surface of the filter body is covered with the copper foil tape, and copper The remaining part of the foil tape is folded and pasted to the back surface of the electromagnetic shielding film, and a transparent gel adhesive sheet is pasted on the entire electromagnetic shielding surface with a laminator at a linear pressure of 3.2 kgf / cm or less and a room temperature laminator. Obtained.
Next, the optical filter was bonded to the front surface (display surface) of the PDP panel with a laminator having a linear pressure of 1.5 kgf / cm or less and a normal temperature (see FIG. 3).
In addition, the same thing as Example 5 was used for the polycarbonate sheet, the antireflection film, the silica vapor deposition high barrier film, the near-infrared cut film, the image quality correction film, the transparent gel adhesive sheet, and the mesh type electromagnetic wave shield sheet.

(Example 8)
An antireflection film is bonded to the front surface of the polycarbonate sheet with a laminator at a linear pressure of 9.6 kgf / cm, and then a silica-deposited high barrier film, a near-infrared cut film, an image quality correction film, a mesh on the back surface of the antireflection film. A filter body was constructed by laminating type electromagnetic shielding films on the back side in order with a laminator having a linear pressure of 9.6 kgf / cm and room temperature.
Next, a copper foil tape with a conductive adhesive (25 mm in width) is attached to the four sides around the front surface of the antireflection film for a width of 10 mm from the edge, and the laminated end surface of the filter body is covered with the copper foil tape, and copper The remaining part of the foil tape is folded and pasted to the back surface of the electromagnetic shielding film, and a transparent gel adhesive sheet is pasted on the entire electromagnetic shielding surface with a laminator at a linear pressure of 3.2 kgf / cm or less and a room temperature laminator. Obtained.
Next, the optical filter was bonded to the front surface (display surface) of the PDP panel with a laminator having a linear pressure of 1.5 kgf / cm or less and a normal temperature (see FIG. 4).
In addition, the same thing as Example 5 was used for the polycarbonate sheet, the antireflection film, the silica vapor deposition high barrier film, the near-infrared cut film, the image quality correction film, the transparent gel adhesive sheet, and the mesh type electromagnetic wave shield sheet.

Example 9
A silica-deposited high barrier film is bonded to both sides of a polycarbonate sheet with a laminator at a linear pressure of 9.6 kgf / cm, and then a near-infrared cut film, an image quality correction film, and a mesh type on the front side of the silica-deposited high barrier film on the front side. The electromagnetic wave shielding film is applied to the front side in order with a laminator with a linear pressure of 9.6 kgf / cm, and a transparent gel adhesive sheet (“Clear Fit” manufactured by Mitsubishi Plastics Co., Ltd., thickness 75 μm) is placed on the mesh part in front of the electromagnetic wave shielding sheet. An antireflection film is laminated with a laminator at a linear pressure of 3.2 kgf / cm or less at room temperature, and a transparent gel adhesive sheet (“Clear Fit” manufactured by Mitsubishi Plastics, thickness 0.5 mm) is further drawn on the back side of the polycarbonate sheet. Bonding with a laminator at room temperature under 3.2kgf / cm To obtain an optical filter for PDP.
The obtained optical filter was bonded to the front surface of the PDP panel with a laminator having a linear pressure of 1.5 kgf / cm or less and a normal temperature (see FIG. 5).
In addition, the same thing as Example 5 was used for the polycarbonate sheet, the antireflection film, the silica vapor deposition high barrier film, the near infrared cut film, the image quality correction film, and the mesh type electromagnetic wave shield sheet.

(Example 10)
After laminating a silica-deposited high barrier film on both sides of the polycarbonate sheet with a laminator at a linear pressure of 9.6 kgf / cm, wire a near-infrared cut film and an image quality correction film on the back side of the silica-deposited high barrier film on the back side. Laminator with a pressure of 9.6 kgf / cm and a room temperature laminator, and a mesh type electromagnetic wave shielding film (manufactured by Nippon Filcon, without mesh surface smoothing, with back surface adhesive) on the surface of the other silica-deposited high barrier film. The anti-reflection film is applied to a laminator with a linear pressure of 3.2 kgf / cm or less and a room temperature through a transparent gel adhesive sheet (“Clear Fit” manufactured by Mitsubishi Plastics, thickness 75 μm) on the front of the mesh portion of the electromagnetic shielding sheet. And then the back of the polycarbonate sheet Transparent gel adhesive sheet (Mitsubishi Plastics, Inc. "clear fit", thickness of 0.5mm) below the line pressure of 3.2kgf / cm, was obtained laminated at room temperature of the laminator, an optical filter for PDP.
The obtained optical filter was bonded to the front surface of the PDP panel with a laminator having a linear pressure of 1.5 kgf / cm or less and a normal temperature (see FIG. 6).
In addition, the same thing as Example 5 was used for the polycarbonate sheet, the antireflection film, the silica vapor deposition high barrier film, the near infrared cut film, the image quality correction film, and the mesh type electromagnetic wave shield sheet.

(Example 11)
After laminating a silica-deposited high barrier film on both sides of a polycarbonate sheet with a laminator at a linear pressure of 9.6 kgf / cm, a mesh type electromagnetic wave shielding film (manufactured by Nippon Filcon Co., Ltd.) is placed on the front side of the silica-deposited high barrier film on the front side. , No mesh surface smoothing treatment, with back surface adhesive) with a laminator in the same manner as above, and through a transparent gel adhesive sheet (“Clear Fit” manufactured by Mitsubishi Plastics, thickness 75 μm) on the front side of the mesh portion of the electromagnetic shielding sheet Then, a near-infrared cut film, an image quality correction film, and an antireflection film were laminated in this order on the front side with a laminator at a linear pressure of 3.2 kgf / cm or less and room temperature. A transparent gel pressure-sensitive adhesive sheet (“Clear Fit” manufactured by Mitsubishi Plastics, thickness 0.5 mm) is pasted to the back of the other silica-deposited high barrier film with a laminator at a linear pressure of 3.2 kgf / cm or less and at room temperature, and an optical filter for PDP Got.
The obtained optical filter was bonded to the front surface of the PDP panel with a laminator having a linear pressure of 1.5 kgf / cm or less and a normal temperature (see FIG. 7).
In addition, the same thing as Example 5 was used for the polycarbonate sheet, the antireflection film, the silica vapor deposition high barrier film, the near infrared cut film, the image quality correction film, and the mesh type electromagnetic wave shield sheet.

(Comparative Example 5)
Example 5 except that the transparent gel adhesive sheet of Example 5 (“Clear Fit” manufactured by Mitsubishi Plastics, thickness 0.5 mm) was changed to a transparent adhesive sheet (“VHBY9410J” manufactured by 3M, thickness 1.0 mm). An optical filter was obtained by the same configuration and manufacturing method, and was similarly bonded to a PDP panel.

(Comparative Example 6)
Example 7 with the exception that the transparent gel adhesive sheet of Example 7 (“Clear Fit” manufactured by Mitsubishi Plastics, thickness 0.5 mm) was changed to a transparent adhesive sheet (“VHBY9410J” manufactured by 3M, thickness 1.0 mm). An optical filter was obtained by the same configuration and manufacturing method, and was similarly bonded to a PDP panel.

(Comparative Example 7)
Except for changing the transparent gel adhesive sheet of Example 7 (Mitsubishi Resin “Clear Fit”, thickness 0.5 mm) to a transparent adhesive sheet (Nitto Denko “trade name: CS-9611”, thickness 25 μm), An optical filter was obtained by the same structure and production method as in Example 7, and was similarly bonded to a PDP panel.

(Comparative Example 8)
A comparison was made except that the transparent adhesive sheet of Comparative Example 7 (“Nitto Denko Corporation“ trade name: CS-9611 ”, thickness 25 μm) was changed to a transparent adhesive sheet (“ Nitto Denko Corporation “trade name: HJ 9150W”, thickness 50 μm). An optical filter was obtained by the same structure and production method as in Example 7, and was similarly bonded to a PDP panel.

  Table 2 shows the results of the following tests using the optical filters and PDP panel structures obtained in Examples 5 to 11 and Comparative Examples 5 to 8.

(1) Initial optical characteristics The optical filters obtained in Examples 5 to 11 and Comparative Examples 5 to 8 were applied to n float glass (soda lime glass, thickness 3 mm) as a substitute for a PDP panel, and a linear pressure of 9.6 kgf / cm. , Pasting with a laminator at room temperature, measuring the transmittance at a wavelength of 300-1200 nm with a spectrophotometer (Hitachi U-4000), required characteristics (luminous average transmittance 40% or more, Ne cut wavelength transmittance 20-30) %, 850-1160 nm transmittance of 10% or less) was evaluated as ○, and unsatisfactory was evaluated as ×.

(2) Laminating property The uneven part of the electromagnetic wave shielding film having the PDP panel structure obtained in Examples 5 to 11 and Comparative Examples 5 to 8 was visually observed using a magnifying glass with a magnification of 10 times, and adhered without bubbles. The case where the bubbles were generated was evaluated as ○ and the case where bubbles were generated was evaluated as ×.

(3) Durability of adhesion to PDP panel Heat resistance: After the PDP panel structure obtained in Examples 5 to 11 is held at 80 ° C. for 500 hours in a hot air circulation dryer, the presence or absence of generation of bubbles in the uneven portion of the electromagnetic shielding film The presence or absence of peeling was confirmed visually. The case where bubbles were not generated and peeled was evaluated as ◯, and the case where bubbles were generated was evaluated as ×.
Heat shock: After the PDP panel structure obtained in Examples 5 to 11 was held in a programmable constant temperature and humidity layer at −20 ° C. 1 Hr⇔80 ° C. 1 Hr for 250 cycles, occurrence of bubbles in the uneven portions of the electromagnetic wave shielding film The presence or absence of peeling was confirmed visually. The case where bubbles were not generated and peeled was evaluated as ◯, and the case where bubbles were generated was evaluated as ×.
Note that Comparative Examples 5 to 8 were not evaluated because the evaluation of the initial lamination property was bad, and it was meaningless to evaluate the durability of adhesion to the PDP panel (heat resistance and heat shock).

It is typical sectional drawing for demonstrating the display panel structure provided with the optical filter for a display which concerns on an example of this invention. It is typical sectional drawing for demonstrating the display panel structure provided with the optical filter for displays concerning the example different from the said example. It is typical sectional drawing for demonstrating the display panel structure provided with the optical filter for displays concerning the example different from the said example. It is typical sectional drawing for demonstrating the display panel structure provided with the optical filter for displays concerning the example different from the said example. It is typical sectional drawing for demonstrating the display panel structure provided with the optical filter for displays concerning the example different from the said example. It is typical sectional drawing for demonstrating the display panel structure provided with the optical filter for displays concerning the example different from the said example. It is typical sectional drawing for demonstrating the display panel structure provided with the optical filter for displays concerning the example different from the said example. It is the perspective view which showed an example of the electromagnetic wave shield film thru | or sheet | seat. It is the principal part expansion perspective view which expanded and showed the mesh part of the electromagnetic wave shielding film thru | or sheet | seat shown in FIG. It is a principal part expanded sectional view which expanded and showed the cross section of the mesh part of the electromagnetic wave shielding film thru | or sheet | seat shown in FIG. It is the principal part expanded sectional view which expanded and showed the cross section at the time of laminating | stacking a transparent gel adhesion layer on the mesh part of the electromagnetic wave shielding film thru | or sheet | seat shown in FIG. It is the disassembled perspective view which showed an example of the surface structure of a PDP panel. It is a figure explaining the test device of a falling ball impact test.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical filter for displays 2 Transparent gel adhesion layer 3 Transparent base | substrate 4 Visible light low reflection layer 5 Near-infrared cut layer 6 Image quality correction layer 7 Electromagnetic wave shielding layer 8 Moisture-permeable prevention layer 9 Conductive adhesive tape 10 Filter main body 11 Most filter body Back side layer 11a Back side 12 Line part 20 Electromagnetic wave shielding film or sheet 20A Peripheral part 20B Inner part 21 Plastic film or sheet 22 Metal thin film 23 Line part 24 Mesh part 100 Display panel 100a Panel front surface 101 Stacked on front panel Layer 101a front

Claims (10)

An optical filter to be bonded to the front side of the display panel,
Transparent as an adhesive layer for adhering to the front surface of the panel of the display panel or any one of the layers laminated on the front surface of the panel, or as an adhesive layer for adhering each layer constituting the optical filter Provided with a transparent gel adhesive layer made of gel adhesive,
The transparent gel-like pressure-sensitive adhesive is characterized in that it is a transparent gel obtained by swelling a three-dimensional crosslinked polymer with a liquid containing a plasticizer and inorganic fine particles. The plasticizer has a freezing point of − The second feature is that the liquid is 20 ° C. or less and is contained in the gel in an amount of 10 to 70% by weight. The inorganic fine particles have a primary average particle size of 200 nm or less, and 1 in the gel. The resin that constitutes the three-dimensional crosslinked polymer has a glass transition temperature (Tg) of −20 ° C. or lower and a melt viscosity at 130 ° C. of 50000 mPa · s or higher. This is a display that is characterized in that, in a test according to JIS Z0237, the load is 490 mN (50 gf) × 2 hours and the holding force at 40 ° C. is 5 mm or less. Optical filter for Lee. On one side or both sides of a transparent substrate made of a transparent film or sheet, a visible light low reflection layer, a near-infrared cut layer, an image quality correction layer, an electromagnetic wave shielding layer, a moisture permeation prevention layer, or these layers Comprising a filter body formed by laminating a plurality of layers composed of a combination of two or more selected from
The optical filter for display according to claim 1, comprising a configuration in which a transparent gel adhesive layer is laminated on the back surface of the filter body. Equipped with an electromagnetic shielding layer as the back side layer of the filter body,
One side edge of the conductive member is connected to the conductive surface of the electromagnetic wave shielding layer, the conductive member covers the end surface of the filter body, and the other side edge of the conductive member is the outermost edge of the filter body. The optical filter for a display according to claim 1, comprising a structure in which a transparent gel adhesive layer is laminated on the conductive surface of the filter body with the one side edge portion of the conductive member interposed therebetween. .   4. The display according to claim 2, wherein in the configuration of the filter body, the surface to be laminated on which the transparent gel adhesive layer is laminated is a concavo-convex pattern surface composed of a linear portion having a convex height of 1 μm to 1 mm. Optical filter.   The display panel front surface to which the transparent gel adhesive layer is bonded or the front surface of the layer laminated on the panel front surface is a concavo-convex pattern surface composed of a linear portion having a convex height of 1 μm to 1 mm. The optical filter for display according to any one of the above.   The optical filter for display according to claim 4 or 5, wherein the concavo-convex pattern surface is a surface composed of a mesh-like line portion. An optical filter to be bonded to the front side of the display panel,
Provided with at least an electromagnetic wave shielding layer on one side or both sides of the transparent substrate,
The electromagnetic wave shielding layer is composed of an electromagnetic wave shielding film or sheet provided with a mesh part consisting of a linear part connected to the peripheral part on the inner part leaving the peripheral part of the film or sheet made of a conductive material,
An optical filter for a display comprising a structure in which a transparent gel adhesive layer is laminated on the mesh portion, and the peripheral portion of the electromagnetic wave shielding film or sheet is exposed.   The transparent gel adhesive layer is a transparent product obtained by photocrosslinking a sheet molded product obtained by sheet-molding a sol composition containing a resin, a crosslinking monomer, a photoinitiator, a plasticizer and inorganic fine particles constituting a three-dimensional crosslinked polymer. The optical filter for display according to any one of claims 1 to 7, wherein the gel pressure-sensitive adhesive sheet is laminated.   The display surface structure provided with the structure formed by laminating | stacking the display optical filter in any one of Claims 1-3 in the front surface of the panel front surface of the display panel, or the frontmost layer laminated | stacked on the said panel front surface. The frontmost layer laminated on the panel front surface of the display panel is an electromagnetic wave shield provided with a mesh part composed of a line part connected to the peripheral part on the inner part leaving the peripheral part of the layer made of a conductive material. It is comprised from the film | membrane thru | or sheet | seat, The optical filter for a display in any one of Claims 1-3 is laminated | stacked on the front surface of the said mesh part, The peripheral part of the electromagnetic wave shielding film was equipped with the structure exposed to the front side. The display surface structure according to claim 9.