WO2009125869A1

WO2009125869A1 - Near-infrared-shielding structure and optical filter for display employing the same

Info

Publication number: WO2009125869A1
Application number: PCT/JP2009/057458
Authority: WO
Inventors: 悠桑山; 頼信石井
Original assignee: 株式会社ブリヂストン
Priority date: 2008-04-11
Filing date: 2009-04-13
Publication date: 2009-10-15

Abstract

A near-infrared-shielding structure is provided which is excellent in the property of shielding near infrared rays and in the durability of the property. The near-infrared-shielding structure is characterized by having a near-infrared-shielding layer (13) comprising: a tungsten oxide and/or a composite tungsten oxide; and a pressure-sensitive adhesive having acid groups.

Description

Near-infrared shield and optical filter for display using the same

The present invention relates to a near-infrared shield having a near-infrared shielding function and a display optical filter having a near-infrared shielding function suitable for a plasma display panel (PDP) and the like.

A front filter is always used for PDP. This front filter is used for the purpose of near-infrared cut, color reproducibility improvement (light emission color purity improvement), electromagnetic wave shield, bright place contrast improvement (antireflection), light emission panel protection, heat insulation from the light emission panel, etc. .

The near-infrared light emitted from the PDP light-emitting panel needs to be reduced in order to avoid malfunctioning the remote control used for home TV and video. In addition, it is necessary to suppress the electromagnetic waves emitted by the light emitting panel of the PDP in order to avoid adverse effects on the human body and precision equipment. Further, in order to make the light emitted from the light emitting panel of the PDP feel a natural color for human vision, there is a demand for improvement in color reproducibility (light emission color purity improvement) by correction with a filter. Furthermore, it is desirable that the display on the display be visually recognized with sufficient contrast without being hindered by reflection of light from the outside even in a bright place such as a bright room. In addition, even when the display product is directly touched by hand, it is desirable that the heat generated by the light emitting panel of the PDP is cut off in order to avoid a situation where the user is surprised by the high temperature.

In general, optical filters having various functions such as antireflection, near-infrared shielding, and electromagnetic wave shielding are used as optical filters for PDPs that meet the above-mentioned purpose. However, in actuality, it is used as an optical filter for PDP by bonding optical filters having respective functions and optical filters having two functions in an appropriate combination.

The near-infrared rays emitted from the above-mentioned plasma display may cause malfunctions of peripheral electronic devices, so that particularly effective blocking is required.

For example, as an optical filter having a function of blocking near infrared rays, Patent Document 1 (Japanese Patent Laid-Open No. 2001-133624) discloses a transparent near infrared ray containing a transparent resin film layer (1) and a diimonium-based compound as a near infrared ray absorbent. It has a multilayer structure in which a shielding layer (2), a transparent resin film layer (3), and a transparent color tone compensation layer (4) containing a color material that compensates the color tone of the transparent near-infrared shielding layer (2) are laminated. The near-infrared shielding film characterized by this is disclosed.

JP 2001-133624 A JP 2006-287236 A (described later)

In order to simplify the structure of the optical filter, there are increasing demands for reducing the number of layers constituting the filter by giving the adhesive layer various functions.

On the other hand, with respect to the near-infrared shielding effect, when a near-infrared shielding layer containing a diimonium compound as a near-infrared absorber as described in Patent Document 1 is used, the near-infrared absorbing function is maintained for a long time. However, it has been revealed by the inventor that the durability is not sufficient. Patent Document 2 (Japanese Patent Laid-Open No. 2006-287236) proposes a tungsten oxide and a composite tungsten oxide (hereinafter also referred to as (composite) tungsten oxide) excellent in near-infrared blocking properties.

The above (composite) tungsten oxide has strong absorption in the near infrared and is extremely effective in preventing malfunction of the peripheral electronic device. Such (composite) tungsten oxide is generally commercially available as a dispersion in which fine particles are dispersed in a medium. In order to form the near-infrared blocking layer, it is necessary to mix this dispersion and the pressure-sensitive adhesive, but according to the study of the present inventors, the fine particles of (composite) tungsten oxide are likely to aggregate due to these mixing, It has been found that the obtained near-infrared shielding layer cannot obtain a predetermined near-infrared absorbing ability.

Therefore, an object of the present invention is to provide a near-infrared shield having excellent near-infrared shielding properties and durability that retains its function over a long period of time.

Another object of the present invention is to provide an optical filter for a display that has excellent near-infrared shielding properties and durability that retains its function for a long period of time, and has improved display characteristics.

Furthermore, an object of the present invention is to provide an optical filter for a plasma display panel which has excellent near-infrared shielding properties and durability for maintaining its function for a long period of time, and has further improved display characteristics.

According to further studies by the present inventors, the pressure-sensitive adhesive that easily causes aggregation of fine particles of (composite) tungsten oxide is a general neutral pressure-sensitive adhesive and has an acidic group (particularly a carboxylic acid group). It has been clarified that the problem of aggregation is solved by using.

The present invention
A near-infrared shield comprising a tungsten oxide and / or a composite tungsten oxide and an adhesive having an acidic group;
It is in.

In the present invention, the adhesive means an adhesive resin and is preferably used together with a curing agent.

Preferred embodiments of the near-infrared shield of the present invention are as follows.
(1) The acid value of the pressure-sensitive adhesive is 0.5 KOH mg / g or more. Tungsten oxide and / or composite tungsten oxide can be well dispersed.
(2) The pressure-sensitive adhesive is an acrylic resin-based pressure-sensitive adhesive.
(3) The acidic group of the pressure-sensitive adhesive is a carboxyl group. Tungsten oxide and / or composite tungsten oxide can be well dispersed.
(4) The near-infrared shield further includes a dye having a maximum absorption in the wavelength range of 560 to 610 nm (neon cut dye). By using a (composite) tungsten oxide and a neon cut pigment in combination, the near-infrared shielding property and the durability thereof can be further improved.
(5) a near-infrared shielding layer containing tungsten oxide and / or composite tungsten oxide, and a neon cut layer containing a dye having a maximum absorption in the wavelength range of 560 to 610 nm. By using a resin (especially acrylic resin) excellent in compatibility with each compound, each function can be exhibited efficiently, so that both the near-infrared blocking function and the neon cut function can be achieved at a high level. Is possible.
(6) It has a near-infrared shielding layer containing both tungsten oxide and / or composite tungsten oxide and a dye having maximum absorption in the wavelength range of 560 to 610 nm. By using a resin (especially acrylic resin) excellent in compatibility with both compounds, it is possible to achieve both a near-infrared blocking function and a neon cut function at a high level.
(7) The tungsten oxide and / or the composite tungsten oxide is in the form of fine particles. Good near-infrared shielding effect.
(8) The average particle size of the fine particles is 400 nm or less. Good near-infrared shielding effect.
(9) The tungsten oxide is represented by the general formula WyOz (where W represents tungsten, O represents oxygen, and 2.2 ≦ z / y ≦ 2.999),
The composite tungsten oxide has the general formula MxWyOz (where M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, One or more elements selected from V, Mo, Ta, Re, Be, Hf, Os, Bi, I, W represents tungsten, O represents oxygen, and 0.001 ≦ x / y ≦ 1,2. 0.2 ≦ z / y ≦ 3). A composite tungsten oxide is preferable because of its excellent near-infrared absorptivity.

The near-infrared shield of the present invention is suitably used as a display optical filter, particularly as a plasma display panel filter.

The near-infrared shield of the present invention contains a tungsten oxide and / or a composite tungsten oxide that efficiently cuts near infrared rays, and contains an adhesive (binder resin) having an acidic group. For this reason, the (composite) tungsten oxide is uniformly dispersed as fine fine particles in the pressure-sensitive adhesive, and exhibits excellent near-infrared shielding properties. Therefore, when such a near-infrared shield is used as an optical filter for display, particularly an optical filter for a PDP, the display image of the obtained PDP is effectively cut off from near-infrared light. Remarkably prevent malfunction. Furthermore, such a near-infrared cut function can be maintained for a long time. At the same time, the visibility of the display image is excellent. For this reason, the near-infrared shield of the present invention has excellent near-infrared shielding properties and durability, and exhibits excellent display characteristics.
Moreover, since the near-infrared shielding body of this invention has the outstanding near-infrared shielding property as mentioned above, it is useful also for uses other than a display, for example, a window glass, a showcase, etc. from the same viewpoint.

It is a schematic sectional drawing of one typical example of the near-infrared shielding body of this invention. It is a schematic sectional drawing of one example of the suitable aspect of the near-infrared shielding body of this invention. It is a schematic sectional drawing of another example of the suitable aspect of the near-infrared shielding body of this invention. It is a schematic sectional drawing of another example of the suitable aspect of the near-infrared shielding body of this invention. It is a schematic sectional drawing of another example of the suitable aspect of the near-infrared shielding body of this invention. It is a schematic sectional drawing of another example of the suitable aspect of the near-infrared shielding body of this invention. It is a schematic sectional drawing of another example of the suitable aspect of the near-infrared shielding body of this invention. It is a schematic sectional drawing of another example of the suitable aspect of the near-infrared shielding body of this invention. It is a schematic sectional drawing of one example of the state in which the near-infrared shielding body of this invention was affixed on the image display surface of the plasma display panel which is 1 type of a display.

The near-infrared shield (display optical filter) of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of the basic configuration of the near-infrared shield of the present invention.

The near-infrared shield of the present invention is provided with a transparent substrate 11, an antireflection layer 12 formed on one surface of the transparent substrate 11, and a near-infrared shielding layer 13 formed on the other surface of the transparent substrate 11. It has a configuration. In the present invention, the near-infrared shielding layer 13 includes both tungsten oxide and / or composite tungsten oxide and an adhesive having an acidic group. Since the near-infrared shielding layer 13 has tungsten oxide and / or composite tungsten oxide dispersed finely in a pressure-sensitive adhesive having an acidic group, harmful near-infrared rays are efficiently cut. Such a near-infrared shield generally has a minimum value of transmittance of near-infrared light in the wavelength region of 800 to 1100 nm of 30% or less. It is preferable that the near-infrared shielding layer 13 is made sticky and used to adhere to another optical film or the display surface. In applications that do not require the antireflection function, the antireflection layer 12 may be omitted.

FIG. 2 shows a schematic sectional view of an example of a preferred embodiment of the near-infrared shield of the present invention. This near-infrared shield is provided with a transparent substrate 21A, an antireflection layer 22 formed on one surface of the transparent substrate 21A, and an adhesive near-infrared shield layer 23 formed on the other surface of the transparent substrate 21A. Layered body (the same mode as the previous FIG. 1), another transparent substrate 21B, a mesh-like conductive layer 24 formed on one surface of the transparent substrate 21B, and neon formed on the other surface of the transparent substrate 21B Another laminated body provided with the pressure-sensitive adhesive layer 25 containing the cut pigment has a configuration in which it is adhered via a near-infrared shielding layer 23 having adhesiveness. In the present invention, the near-infrared shielding layer 23 includes both tungsten oxide and / or composite tungsten oxide and an adhesive having an acidic group. Since the near-infrared shielding layer 23 has tungsten oxide and / or composite tungsten oxide dispersed in a pressure-sensitive adhesive having fine particles and uniform acidic groups, harmful near-infrared rays are efficiently cut off. Such a near-infrared shield generally has a minimum value of transmittance of near-infrared light in the wavelength region of 800 to 1100 nm of 30% or less. For this reason, a display provided with such a near-infrared shield as an optical filter, particularly a PDP, exhibits excellent display characteristics.

Such a near-infrared shield is generally adhered to the display surface via the pressure-sensitive adhesive layer 25, or is adhered to a glass plate via the pressure-sensitive adhesive layer 25 and disposed on the front surface of the PDP.

FIG. 3 shows an example of another preferred embodiment of the near-infrared shield of the present invention. A mesh-like conductive layer (electromagnetic wave shielding layer) 34 is provided on one surface of the transparent substrate 31, an antireflection layer 32 is further provided on the conductive layer 34, and a near-infrared shielding layer is provided on the other surface of the transparent substrate 31. 33 is provided. Therefore, only one transparent substrate 31 is used as the substrate, and a thin substrate can be obtained as compared with the near-infrared shield in FIG. In this near-infrared shielding body, the near-infrared shielding layer 33 is composed of tungsten oxide and / or composite tungsten oxide dispersed finely in a pressure-sensitive adhesive having an acidic group. Cut well. Such a near-infrared shield generally has a minimum value of transmittance of near-infrared light in the wavelength region of 800 to 1100 nm of 30% or less.

Also, as described above, the antireflection layer in the near-infrared shield can be omitted depending on the application. An example of another preferred embodiment of such a near-infrared shield of the present invention is shown in FIG. In this near-infrared shield, a transparent substrate 41A, a near-infrared shielding layer 43 formed on one surface of the transparent substrate 41A, and a mesh adhered to the other surface of the transparent substrate 41A via an adhesive layer 46 The laminated body having the conductive layer 44 and the transparent substrate 41 </ b> B are laminated via the near infrared shielding layer 43. The near-infrared shield has a simplified configuration because it does not have an antireflection layer, and is easy to manufacture. Moreover, such a near-infrared shielding body can be arrange | positioned as it is in front of PDP. The near-infrared shielding layer 43 includes both tungsten oxide and / or composite tungsten oxide and an adhesive having an acidic group. Therefore, the tungsten oxide and / or the composite tungsten oxide are uniformly finely dispersed in the near infrared shielding layer, and the near infrared can be cut efficiently. Such a near-infrared shield generally has a minimum value of the transmittance of near-infrared light in the wavelength region of 800 to 1100 nm as described above.

An example of still another preferred embodiment of the near-infrared shield of the present invention is shown in FIG. The near-infrared shield was formed on the transparent substrate 51A, the mesh-like conductive layer 54 pasted on one surface of the transparent substrate 51A via the adhesive layer 56, and the mesh-like conductive layer 54. The laminated body which has the near-infrared shielding layer 53, and the transparent substrate 51B have the structure laminated | stacked so that the near-infrared shielding layer 53 and the transparent substrate 51B may adjoin. The near-infrared shield has a simplified configuration because it does not have an antireflection layer, and is easy to manufacture. Moreover, such a near-infrared shielding body can also be arrange | positioned as it is on the front surface of PDP. The near-infrared shielding layer 53 includes both tungsten oxide and / or composite tungsten oxide and an adhesive having an acidic group. Therefore, the tungsten oxide and / or the composite tungsten oxide are uniformly finely dispersed in the near infrared shielding layer, and the near infrared can be cut efficiently. Such a near-infrared shield generally has a minimum value of the transmittance of near-infrared light in the wavelength region of 800 to 1100 nm as described above.

The near-infrared shield of the present invention preferably further contains a dye (neon cut dye) having a maximum absorption in the wavelength range of 560 to 610 nm. By using a neon cut pigment, unnecessary light derived from neon gas that can be generated from PDP or the like can be cut, and the visibility of a display image can be improved.

The neon cut pigment may be contained in any layer used for the near-infrared shield. Therefore, the near-infrared shielding layer, the pressure-sensitive adhesive layer, and the like may contain a neon cut pigment. Moreover, you may further use the neon cut layer containing a neon cut pigment | dye for a near-infrared shield. The neon cut layer generally contains a dye having a maximum absorption in a wavelength region of 560 to 610 nm and a binder resin for dispersing the dye. In such a neon cut layer, since the dye is uniformly dissolved and / or dispersed in the resin, light from harmful neon gas is efficiently cut.

FIG. 6 shows a preferred embodiment of a near-infrared shield having a neon cut layer. The near-infrared shield includes a transparent substrate 61, an antireflection layer 62 formed on one surface of the transparent substrate 61, and a neon cut layer 64 and a near-infrared shield layer 63 that are sequentially stacked on the other surface of the transparent substrate 61. Consists of

Another preferred embodiment of the near-infrared shield having a neon cut layer is shown in FIG. This near-infrared shield is a transparent substrate 71A, an antireflection layer 72 formed on one surface of the transparent substrate 71A, and neon (may have adhesiveness) formed on the other surface of the transparent substrate 71A. A laminate composed of a cut layer 74 and a near-infrared shielding layer 73 having adhesiveness (the same mode as in the previous FIG. 1), another transparent substrate 71B, and a mesh-like conductive layer formed on one surface of the transparent substrate 71B 75 and another laminate composed of the pressure-sensitive adhesive layer 76 formed on the other surface of the transparent substrate 71B have a configuration in which they are bonded via a near-infrared shielding layer 73 having adhesiveness.

Another preferred embodiment of the near-infrared shield having a neon cut layer is shown in FIG. 8 (embodiment using one transparent substrate). A mesh-like conductive layer (electromagnetic wave shielding layer) 85 is provided on one surface of the transparent substrate 81, and an antireflection layer 82 is further provided on the conductive layer 85. A neon cut layer 84 and a near-infrared shielding layer 83 having adhesiveness may be provided. An adhesive layer 86 may be further provided on the near-infrared shielding layer 83. In this near-infrared shield, only one transparent substrate 81 is used as a substrate, and a thin substrate can be obtained as compared with the near-infrared shield in FIG. Alternatively, an adhesive near-infrared shielding layer 83 and an adhesive neon-cut layer 84 are provided on a mesh-like conductive layer (electromagnetic wave shielding layer) 85, and the neon-cut layer 84 and the near-infrared shielding layer 83 are provided. Instead, an antireflection layer 82 may be provided.

6 to 8, the near-infrared shielding layers 63, 73, and 83 include tungsten oxide and / or composite tungsten oxide and an adhesive having an acidic group. Therefore, the tungsten oxide and / or the composite tungsten oxide are uniformly finely dispersed in the near infrared shielding layer, and the near infrared can be cut efficiently. 6 to 8 as described above, as described above, generally, the minimum value of the transmittance of near infrared light in the wavelength region of 800 to 1100 nm is 30% or less. The neon cut layers 64, 74, and 84 include a dye having a maximum absorption in a wavelength region of 560 to 610 nm and a binder resin that disperses the dye. In such a neon cut layer, since the dye is uniformly dissolved and / or dispersed in the resin, light from harmful neon gas is efficiently cut.

The near-infrared shielding body of the present invention has any configuration as long as it includes a layer in which tungsten oxide and / or composite tungsten oxide is dispersed in a pressure-sensitive adhesive that is finely divided and has acidic groups. Alternatively, a layer having a configuration other than that shown in FIGS. 1 to 8, for example, the position of the layer shown above may be appropriately changed.

In the near-infrared shield of the present invention, the minimum value of the transmittance in the near-infrared ray in the wavelength range of 800 to 1100 nm is preferably 30% or less in the wavelength range. Thereby, harmful near infrared rays are efficiently cut. In particular, it is more preferable that the minimum transmittance of visible light in the wavelength range of 560 to 610 nm is 60% or less in the wavelength range. The neon cut pigment may be contained in an appropriate layer such as an adhesive layer or a near infrared shielding layer, or a neon cut layer containing a neon cut pigment may be used.

As described above, the near-infrared shield of the present invention can efficiently cut harmful near-infrared rays, and can maintain excellent near-infrared cutability over a long period of time. At the same time, the visibility of the display image is excellent. Therefore, the near-infrared shield of the present invention is preferably used as an optical filter for display, particularly as an optical filter for plasma panel display.

In the present invention, generally, the antireflection layer is a hard coat layer; it is composed of a hard coat layer and a low refractive index layer having a refractive index lower than that of the hard coat layer (in this case, the hard coat layer is in contact with the metal conductive layer). Or a hard coat layer, a high refractive index layer having a higher refractive index than the hard coat layer, and a low refractive index layer having a lower refractive index than the hard coat layer (in this case, the hard coat layer is in contact with the metal conductive layer). ). The more layers, the better the antireflection properties are generally obtained. Alternatively, it is also preferable that the antireflection layer comprises an antiglare layer, or an antiglare layer and a low refractive index layer having a lower refractive index than the antiglare layer (the antiglare layer is in contact with the metal conductive layer). The antiglare layer is a so-called antiglare layer, generally has an excellent antireflection effect, and it is often unnecessary to provide an antireflection layer such as a low refractive index layer.

2 and 3 show examples of the near-infrared shielding layer and the adhesive layer, but a near-infrared shielding layer, a neon cut layer, and an adhesive layer may be used. Or it consists of the transparent adhesive layer which has a near-infrared absorption function and a neon cut function, or consists of the near-infrared shielding layer which has a neon cut function, and an adhesive layer (it is provided on the transparent substrate in this order). Or it is also preferable that it consists of a near-infrared shielding layer, a neon cut layer, and an adhesive layer (provided on the transparent substrate in this order).

As the conductive layer, a mesh-like metal layer or a metal-containing layer is shown above, but a metal oxide layer (dielectric layer) or an alternately laminated film of a metal oxide layer and a metal layer may also be used. . The mesh-like metal layer or metal-containing layer is generally formed by etching or printing, or is a metal fiber layer. This makes it easy to obtain low resistance. In general, the mesh gap of the mesh-like metal layer or metal-containing layer is filled with an adhesive (or an adhesive near-infrared shielding layer). This improves transparency. When not filled with an adhesive, it may be filled with another layer, for example, a hard coat layer or the like, or a transparent resin layer dedicated thereto.

The near-infrared shielding layer has a function of blocking unnecessary light from the PDP. In general, it is a layer containing the tungsten oxide and / or composite tungsten oxide of the present invention (including a compound having a maximum absorption in a wavelength region of 300 to 500 nm if necessary). The pressure-sensitive adhesive layer is provided for easy mounting on the display. A release sheet may be provided on the transparent adhesive layer.

The neon cut layer generally contains a dye having a maximum absorption in a wavelength region of 560 to 610 nm and a binder resin for dispersing the dye. As shown in FIGS. 6 to 8, when the near-infrared shielding function and the neon cut function are provided as separate layers, each function can be efficiently performed by using a resin (particularly acrylic resin) excellent in compatibility with each compound. Since it can be exhibited, it is possible to achieve both a near infrared ray blocking function and a neon cut function at a high level. Even when a near-infrared shielding function and a neon cut function are provided as a single layer, such as a near-infrared shielding layer further containing a dye having a maximum absorption in the wavelength region of 300 to 500 nm, it is compatible with both compounds. By using an excellent resin (particularly acrylic resin), it is possible to achieve both a near-infrared blocking function and a neon cut function at a considerably high level.

The near-infrared shield of the present invention is obtained, for example, by forming an antireflection layer over the entire surface of the transparent substrate, and forming a near-infrared shielding layer on the back surface of the transparent substrate and a transparent adhesive layer thereon. . Further, for example, a mesh-like metal conductive layer is formed over the entire surface of the transparent substrate, then an antireflection layer is formed over the entire mesh-like metal conductive layer, and a near-infrared shielding layer and a back surface of the transparent substrate are formed. It can also be obtained by forming a transparent adhesive layer thereon. Alternatively, using two transparent substrates, for example, on the conductive layer of a transparent substrate having a mesh-like conductive layer (generally having a pressure-sensitive adhesive layer or the like on the back surface), an antireflection layer on the front surface and an adhesive near-infrared surface on the back surface It can also be obtained by laminating and bonding a transparent substrate having a shielding layer via a near-infrared shielding layer. Alternatively, an antireflection layer such as a mesh-like metal conductive layer, an antiglare layer and a low refractive index layer is provided in this order on the surface of the transparent substrate, and the near infrared shielding layer and the upper layer are provided on the surface of another transparent substrate. A transparent pressure-sensitive adhesive layer is provided on the surface, and the surfaces of the two transparent substrates that are not provided are bonded to each other. In this case, the former laminate is produced by the method of the present invention.

The near-infrared shield of the present invention is obtained, for example, by forming an antireflection layer over the entire surface of the transparent substrate, and forming a neon cut layer on the back surface of the transparent substrate and a near-infrared shielding layer thereon. It is done. Also, for example, a mesh-like metal conductive layer is formed over the entire surface of the transparent substrate, then an antireflection layer is formed over the entire mesh-like metal conductive layer, and a neon cut layer and its It can also be obtained by forming an adhesive near-infrared shielding layer on top. Alternatively, using two transparent substrates, for example, on the conductive layer of a transparent substrate having a mesh-like conductive layer (generally having an adhesive layer or the like on the back surface), an antireflection layer on the front surface and a neon cut layer and adhesive on the back surface. It can also be obtained by laminating and adhering a transparent substrate having a near-infrared shielding layer via the near-infrared shielding layer.

The materials used for the near-infrared shield of the present invention will be described below.

The substrate is generally a transparent substrate, and is particularly preferably a transparent plastic film. The material is not particularly limited as long as it is transparent (meaning “transparent to visible light”). Examples of plastic films include polyester {eg, polyethylene terephthalate (PET), polybutylene terephthalate}, polymethyl methacrylate (PMMA), acrylic resin, polycarbonate (PC), polystyrene, triacetate resin, polyvinyl alcohol, polyvinyl chloride, poly Examples thereof include vinylidene chloride, polyethylene, ethylene-vinyl acetate copolymer, polyvinyl butyral, metal ion crosslinked ethylene-methacrylic acid copolymer, polyurethane, and cellophane. Among these, polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), etc. are highly resistant to loads during processing (heat, solvent, bending, etc.) and particularly highly transparent. preferable. In particular, PET is preferable because it has excellent processability. In addition, glass plates such as green glass, silicate glass, inorganic glass plate, and non-colored transparent glass plate are also preferable.

The thickness of the transparent substrate varies depending on the use of the near-infrared shield, but is generally preferably 1 μm to 10 mm, 1 μm to 5 mm, and particularly preferably 25 to 250 μm.

The surface resistance value of the metal conductive layer of the present invention is generally set to 10Ω / □ or less, preferably in the range of 0.001 to 5Ω / □, particularly 0.005 to 5Ω / □. A mesh (lattice) conductive layer is preferred. Alternatively, the conductive layer may be a layer obtained by a vapor deposition method (a transparent conductive thin film of metal oxide (ITO or the like)). Further, it may be an alternate laminate of a metal oxide dielectric film such as ITO and a metal layer such as Ag (eg, ITO / silver / ITO / silver / ITO laminate).

The mesh-like metal conductive layer is made of metal fibers and metal-coated organic fibers made of a metal, or a copper foil layer on a transparent substrate is etched into a mesh to provide openings, on a transparent substrate Examples thereof include a conductive ink printed in a mesh shape.

In the case of a mesh-like metal conductive layer, the mesh preferably has a line width of 1 μm to 1 mm made of metal fibers and / or metal-coated organic fibers and an aperture ratio of 50% or more. A more preferable wire diameter is 10 to 500 μm, and an aperture ratio is 50 to 95%. In a mesh-like conductive layer, when the line width exceeds 1 mm, the electromagnetic wave shielding property is improved, but the aperture ratio is lowered and cannot be compatible. If it is less than 1 μm, the strength as a mesh is lowered and handling becomes difficult. Further, if the aperture ratio exceeds 95%, it is difficult to maintain the shape as a mesh. If the aperture ratio is less than 50%, the light transmittance decreases and the light amount from the display also decreases.

Note that the aperture ratio of the conductive mesh refers to the area ratio occupied by the opening portion in the projected area of the conductive mesh.

The metal fibers constituting the mesh-like conductive layer and the metal of the metal-coated organic fiber include copper, stainless steel, aluminum, nickel, titanium, tungsten, tin, lead, iron, silver, carbon or alloys thereof, preferably copper, Stainless steel and nickel are used.

Polyester, nylon, vinylidene chloride, aramid, vinylon, cellulose, etc. are used as the organic material for the metal-coated organic fiber.

In the case where a conductive foil such as a metal foil is subjected to pattern etching, copper, stainless steel, aluminum, nickel, iron, brass, or an alloy thereof, preferably copper, stainless steel, or aluminum is used as the metal of the metal foil.

If the thickness of the metal foil is too thin, it is not preferable in terms of handleability and workability of pattern etching, and if it is too thick, it affects the thickness of the film obtained, and the time required for the etching process becomes long. It is preferably about 1 to 200 μm.

The shape of the etching pattern is not particularly limited, and examples thereof include a grid-like metal foil in which square holes are formed, and a punching metal-like metal foil in which circular, hexagonal, triangular or elliptical holes are formed. It is done. Further, the holes are not limited to those regularly arranged, and may be a random pattern. The area ratio of the opening on the projection surface of the metal foil is preferably 20 to 95%. Further, those having an aperture ratio of 50% or more are preferable, and particularly 50% or more and 95% or less. The line width is preferably 10 to 500 μm.

In addition to the above, as a mesh-shaped metal conductive layer, dots are formed on the film surface by a material soluble in a solvent, and a conductive material layer made of a conductive material insoluble in a solvent is formed on the film surface. A mesh-like metal conductive layer obtained by removing the dots and the conductive material layer on the dots by bringing the film surface into contact with a solvent may be used.

The conductive layer may be provided directly on the substrate, or may be provided via an adhesive layer or an adhesive layer. As this pressure-sensitive adhesive layer or adhesive layer, the same layer as described later as an adhesive layer for adhering the optical film to the display is used.

A metal plating layer may be further provided on the mesh-like metal conductive layer in order to improve conductivity (particularly, in the case of forming dots with a material soluble in the solvent). The metal plating layer can be formed by a known electrolytic plating method or electroless plating method. As the metal used for plating, generally, copper, copper alloy, nickel, aluminum, silver, gold, zinc, tin or the like can be used, preferably copper, copper alloy, silver, or nickel, In particular, it is preferable to use copper or a copper alloy from the viewpoint of economy and conductivity.

Also, antiglare performance may be imparted. When this anti-glare treatment is performed, a blackening treatment may be performed on the surface of the (mesh) conductive layer. For example, oxidation treatment of a metal film, black plating such as chromium alloy, application of black or dark ink, and the like can be performed.

The antireflection layer of the present invention is generally a composite film of a hard coat layer and a low refractive index layer having a lower refractive index than the hard coat layer provided thereon, or a hard coat layer and a low refractive index layer. It is a composite film in which a high refractive index layer is further provided therebetween. The antireflection film is effective even if it is only a hard coat layer having a refractive index lower than that of the substrate.

The hard coat layer is a layer mainly composed of a synthetic resin such as an acrylic resin layer, an epoxy resin layer, a urethane resin layer, or a silicon resin layer. Usually, the thickness is 1 to 50 μm, preferably 1 to 10 μm. The synthetic resin is generally a thermosetting resin or an ultraviolet curable resin, and an ultraviolet curable resin is preferable. The ultraviolet curable resin is preferable because it can be cured in a short time and has excellent productivity.

Examples of the thermosetting resin include phenol resin, resorcinol resin, urea resin, melamine resin, epoxy resin, acrylic resin, urethane resin, furan resin, and silicon resin.

As the hard coat layer, a cured layer of a layer mainly composed of an ultraviolet curable resin composition (consisting of an ultraviolet curable resin (monomer and / or oligomer), a photopolymerization initiator, etc.) is preferable, and the thickness thereof is usually The thickness is 1 to 50 μm, preferably 1 to 10 μm.

Examples of the ultraviolet curable resin (monomer, oligomer) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 2-ethylhexyl polyethoxy (meth) acrylate. , Benzyl (meth) acrylate, isobornyl (meth) acrylate, phenyloxyethyl (meth) acrylate, tricyclodecane mono (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, acryloylmorpholine N-vinylcaprolactam, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, o-phenylphenyloxyethyl (meth) acrylate, neopentyl Cold di (meth) acrylate, neopentyl glycol dipropoxy di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, tricyclodecane dimethylol di (meth) acrylate, 1,6-hexanediol di (meth) Acrylate, nonanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, tris [(meth) acryloxyethyl] isocyanurate, ditrimethylolpropane (Meth) acrylate monomers such as tetra (meth) acrylate; polyol compounds (eg, ethylene glycol, propylene glycol, neopentyl glycol) 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 2-ethyl-2-butyl-1,3-propanediol, trimethylolpropane, diethylene glycol, dipropylene glycol, Polyols such as polypropylene glycol, 1,4-dimethylolcyclohexane, bisphenol A polyethoxydiol, polytetramethylene glycol, the polyols and succinic acid, maleic acid, itaconic acid, adipic acid, hydrogenated dimer acid, phthalic acid, Polyester polyols which are reaction products of polybasic acids such as isophthalic acid and terephthalic acid or their acid anhydrides, polycaprolactone polyols which are reaction products of the polyols and ε-caprolactone, the polyols and the above A polybasic acid or Reaction products of these acid anhydrides with ε-caprolactone, polycarbonate polyol, polymer polyol, etc.) and organic polyisocyanates (eg, tolylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, diphenylmethane-4,4′-diisocyanate, Dicyclopentanyl diisocyanate, hexamethylene diisocyanate, 2,4,4′-trimethylhexamethylene diisocyanate, 2,2′-4-trimethylhexamethylene diisocyanate, etc.) and a hydroxyl group-containing (meth) acrylate (for example, 2-hydroxyethyl ( (Meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate Relate, cyclohexane-1,4-dimethylol mono (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, glycerin di (meth) acrylate, etc.) (Meth) such as bisphenol type epoxy (meth) acrylate, which is a reaction product of bisphenol type epoxy resin such as polyurethane (meth) acrylate, bisphenol A type epoxy resin, bisphenol F type epoxy resin and (meth) acrylic acid which is a reaction product Examples include acrylate oligomers. These compounds can be used alone or in combination. These ultraviolet curable resins may be used as a thermosetting resin together with a thermal polymerization initiator.

For the hard coat layer, among the above UV curable resins (monomer, oligomer), pentaerythritol tri (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane It is preferable to mainly use a hard polyfunctional monomer such as tri (meth) acrylate.

As the photopolymerization initiator for the ultraviolet curable resin, any compound suitable for the properties of the ultraviolet curable resin can be used. For example, acetophenone such as 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropane-1 Benzoin, such as benzyldimethyl ketal, benzophenone, 4-phenylbenzophenone, benzophenone, such as hydroxybenzophenone, thioxanthone, such as isopropylthioxanthone, 2-4-diethylthioxanthone, and other special types include methylphenyl glyoxylate Etc. can be used. Particularly preferably, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropane-1, Examples include benzophenone. These photopolymerization initiators may be optionally selected from one or more known and commonly used photopolymerization accelerators such as a benzoic acid system such as 4-dimethylaminobenzoic acid or a tertiary amine system. It can be used by mixing at a ratio. Moreover, it can be used by 1 type, or 2 or more types of mixture of only a photoinitiator. Particularly preferred is 1-hydroxycyclohexyl phenyl ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals).

The amount of the photopolymerization initiator is generally 0.1 to 10% by mass, preferably 0.1 to 5% by mass, based on the resin composition.

Furthermore, the hard coat layer may contain a small amount of an ultraviolet absorber, an infrared absorber, an anti-aging agent, a paint processing aid, a colorant and the like. In particular, it is preferable to contain an ultraviolet absorber (for example, a benzotriazole-based ultraviolet absorber or a benzophenone-based ultraviolet absorber), whereby yellowing of the filter can be efficiently prevented. The amount thereof is generally 0.1 to 10% by mass, preferably 0.1 to 5% by mass, based on the resin composition.

The high refractive index layer is made of a polymer (preferably UV curable resin composition), ITO, ATO, Sb ₂ O ₃ , SbO ₂ , In ₂ O ₃ , SnO ₂ , ZnO, Al-doped ZnO, TiO _2. It is preferable to use a layer in which is dispersed (cured layer). The metal oxide fine particles preferably have an average particle size of 10 to 10,000 nm, preferably 10 to 50 nm. In particular, ITO (especially having an average particle diameter of 10 to 50 nm) is preferred. Those having a refractive index of 1.64 or more are suitable. The film thickness is generally in the range of 10 to 500 nm, preferably 20 to 200 nm.

When the high refractive index layer is a conductive layer, the minimum reflectance of the surface reflectance of the antireflection film should be within 1.5% by setting the refractive index of the high refractive index layer to 1.64 or more. By setting the value to 1.69 or more, preferably 1.69 to 1.82, the minimum reflectance of the surface reflectance of the antireflection film can be within 1.0%.

The low refractive index layer is a layer (cured) in which fine particles such as silica and fluororesin, preferably 10 to 40% by mass (preferably 10 to 30% by mass) of hollow silica are dispersed in a polymer (preferably UV curable resin). Layer). The refractive index of the low refractive index layer is preferably 1.45 or less. When the refractive index is more than 1.45, the antireflection characteristic of the antireflection film is deteriorated. The film thickness is generally in the range of 10 to 500 nm, preferably 20 to 200 nm.

As the hollow silica, those having an average particle diameter of 10 to 100 nm, preferably 10 to 50 nm, and a specific gravity of 0.5 to 1.0, preferably 0.8 to 0.9 are preferable.

The hard coat layer preferably has a visible light transmittance of 70% or more. Both the visible light transmittance of the high refractive index layer and the low refractive index layer are preferably 85% or more.

When the antireflection layer is composed of the hard coat layer and the above two layers, for example, the thickness of the hard coat layer is 2 to 20 μm, the thickness of the high refractive index layer is 50 to 150 nm, and the thickness of the low refractive index layer is A thickness of 50 to 150 nm is preferable.

In order to form each layer of the antireflection layer, for example, as described above, the above-mentioned fine particles are blended with a polymer (preferably an ultraviolet curable resin) as necessary, and the obtained coating liquid is used as the transparent substrate. After coating on the surface and then drying, it may be cured by irradiation with ultraviolet rays. In this case, each layer may be applied and cured one by one, or all the layers may be applied and then cured together.

As a specific method of coating, a method of coating a coating solution in which an ultraviolet curable resin containing an acrylic monomer or the like is made into a solution with a solvent such as toluene is coated with a gravure coater, and then dried, and then cured by ultraviolet rays. Can be mentioned. This wet coating method has the advantage that the film can be uniformly formed at high speed at low cost. After this coating, for example, by irradiating and curing with ultraviolet rays, the effect of improving the adhesion and increasing the hardness of the film can be obtained. The conductive layer can be formed similarly.

In the case of ultraviolet curing, many light sources that emit light in the ultraviolet to visible range can be used as the light source. For example, ultra-high pressure, high pressure, low pressure mercury lamp, chemical lamp, xenon lamp, halogen lamp, mercury lamp, carbon arc lamp, incandescent lamp And laser light. Irradiation time is not generally determined by the type of lamp and the intensity of the light source, but it is about several seconds to several minutes. In order to accelerate curing, the laminate may be preheated to 40 to 120 ° C. and irradiated with ultraviolet rays.

As described above, it is also preferable to provide an antiglare layer instead of the hard coat layer. What has a large antireflection effect is easily obtained. As the antiglare layer, for example, an antiglare layer obtained by applying and drying a liquid in which a transparent filler (preferably an average particle size of 1 to 10 μm) such as polymer fine particles (eg, acrylic beads) is dispersed in a binder, Or the anti-glare layer which has the hard-coat function which apply | coated and hardened the liquid which added the transparent filler (polymer fine particle; for example, acrylic beads) to the above-mentioned hard-coat layer formation material can be mentioned, and is preferable. The layer thickness of the antiglare layer is generally in the range of 0.01 to 20 μm.

As described above, the near-infrared shield of the present invention has a near-infrared shielding layer containing tungsten oxide and / or composite tungsten oxide that efficiently cuts near infrared rays and a resin having an acidic group. By using a pressure-sensitive adhesive having an acidic group, tungsten oxide and / or composite tungsten oxide can be uniformly dispersed in the resin in the form of fine particles, whereby the near infrared cut function of (composite) tungsten oxide. Can be fully exhibited. In general, (composite) tungsten oxide is commercially available in a dispersed state, and when the resin having an acidic group of the present invention is not used, it easily aggregates and a uniform dispersed state cannot be obtained. It is difficult to obtain an infrared cut function.

The compound having the maximum absorption in the wavelength region of 300 to 500 nm is preferably contained in any layer.

The tungsten oxide is an oxide represented by the general formula WyOz (W is tungsten, O is oxygen, 2.2 ≦ z / y ≦ 2.999), and the composite tungsten oxide is the tungsten oxide. The element M (where M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, 1 or more elements selected from Ta, Re, Be, Hf, Os, Bi, and I). As a result, free electrons are generated in WyOz, including the case of z / y = 3.0, and free electron-derived absorption characteristics are expressed in the near infrared region, which is effective as a near infrared absorbing material near 1000 nm. . In the present invention, composite tungsten oxide is preferable.

In the tungsten oxide fine particles represented by the general formula WyOz (W is tungsten, O is oxygen, 2.2 ≦ z / y ≦ 2.999), the preferable composition range of tungsten and oxygen is When the composition ratio of oxygen is less than 3 and the infrared shielding material is described as WyOz, 2.2 ≦ z / y ≦ 2.999. If the value of z / y is 2.2 or more, it is possible to avoid the appearance of a crystal phase of WO ₂ which is not intended in the infrared shielding material and to obtain chemical stability as a material. Therefore, it can be applied as an effective infrared shielding material. On the other hand, if the value of z / y is 2.999 or less, a required amount of free electrons is generated and an efficient infrared shielding material can be obtained.

From the viewpoint of stability, the composite tungsten oxide fine particles are generally MxWyOz (where M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, One or more elements selected from Br, Te, Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os, Bi, and I, W is tungsten, O is oxygen, (0.001 ≦ x / Y ≦ 1, 2.2 ≦ z / y ≦ 3) The alkali metal is a group 1 element of the periodic table excluding hydrogen, and the alkaline earth metal is the second element of the periodic table. Group elements and rare earth elements are Sc, Y and lanthanoid elements

In particular, from the viewpoint of improving optical characteristics and weather resistance as an infrared shielding material, the M element is one or more of Cs, Rb, K, Tl, In, Ba, Li, Ca, Sr, Fe, and Sn. Some are preferred. The composite tungsten oxide is preferably treated with a silane coupling agent. Excellent dispersibility is obtained, and an excellent infrared cut function and transparency are obtained.

If the value of x / y indicating the amount of element M added is greater than 0.001, a sufficient amount of free electrons is generated, and a sufficient infrared shielding effect can be obtained. As the amount of the element M added increases, the supply amount of free electrons increases and the infrared shielding effect also increases, but the value of x / y is saturated at about 1. Moreover, if the value of x / y is smaller than 1, it is preferable because an impurity phase can be prevented from being generated in the fine particle-containing layer.

Regarding the value of z / y indicating the control of the amount of oxygen, in the composite tungsten oxide represented by MxWyOz, the same mechanism as that of the infrared shielding material represented by WyOz described above works, and z / y = Even in 3.0, since there is a supply of free electrons due to the addition amount of the element M described above, 2.2 ≦ z / y ≦ 3.0 is preferable, and 2.45 ≦ z / y ≦ 3.0 is more preferable. It is.

Furthermore, when the composite tungsten oxide fine particles have a hexagonal crystal structure, the transmission of the fine particles in the visible light region is improved and the absorption in the near infrared region is improved.

When the cation of the element M is added to the hexagonal void, the transmission in the visible light region is improved and the absorption in the near infrared region is improved. Here, generally, when the element M having a large ionic radius is added, the hexagonal crystal is formed. Specifically, Cs, K, Rb, Tl, In, Ba, Sn, Li, Ca, Sr, When Fe is added, hexagonal crystals are easily formed. Of course, other elements may be added as long as the additive element M exists in the hexagonal void formed by the WO ₆ unit, and is not limited to the above elements.

When the composite tungsten oxide fine particles having a hexagonal crystal structure have a uniform crystal structure, the addition amount of the additive element M is preferably 0.2 or more and 0.5 or less in terms of x / y, more preferably 0. .33. When the value of x / y is 0.33, it is considered that the additive element M is arranged in all of the hexagonal voids.

Besides hexagonal crystals, tetragonal and cubic tungsten bronzes also have an infrared shielding effect. These crystal structures tend to change the absorption position in the near infrared region, and the absorption position tends to move to the longer wavelength side in the order of cubic <tetragonal <hexagonal. Further, the accompanying absorption in the visible light region is small in the order of hexagonal crystal <tetragonal crystal <cubic crystal. For this reason, it is preferable to use hexagonal tungsten bronze for applications that transmit light in the visible light region and shield light in the infrared region.

The particle diameter of the composite tungsten oxide fine particles used in the present invention preferably has a particle diameter (average particle diameter) of 800 nm or less from the viewpoint of maintaining transparency. This is because particles smaller than 800 nm do not completely block light due to scattering, can maintain visibility in the visible light region, and at the same time can efficiently maintain transparency. In particular, when importance is attached to transparency in the visible light region, it is preferable to further consider scattering by particles. When importance is attached to the reduction of scattering by the particles, the particle size is 400 nm or less, preferably 200 nm or less.

Moreover, it is preferable from the viewpoint of improving the weather resistance that the surface of the composite tungsten oxide fine particles of the present invention is coated with an oxide containing one or more of Si, Ti, Zr, and Al.

The composite tungsten oxide fine particles of the present invention are produced, for example, as follows.

The tungsten oxide fine particles represented by the general formula WyOz and / or the composite tungsten oxide fine particles represented by MxWyOz are obtained by heat-treating a tungsten compound starting material in an inert gas atmosphere or a reducing gas atmosphere. Can do.

The tungsten compound starting material is obtained by dissolving tungsten trioxide powder, tungsten oxide hydrate, tungsten hexachloride powder, ammonium tungstate powder, or tungsten hexachloride in alcohol and then drying. Tungsten oxide hydrate powder, or tungsten oxide hydrate powder obtained by dissolving tungsten hexachloride in alcohol and then adding water to precipitate and drying it, or ammonium tungstate It is preferable that it is at least one selected from a tungsten compound powder obtained by drying an aqueous solution and a metal tungsten powder.

Here, when producing tungsten oxide fine particles, it is preferable to use tungsten oxide hydrate powder or tungsten compound powder obtained by drying an ammonium tungstate aqueous solution from the viewpoint of the ease of the production process. More preferably, when producing the composite tungsten oxide fine particles, an ammonium tungstate aqueous solution or a tungsten hexachloride solution is further used from the viewpoint that each element can be easily and uniformly mixed when the starting material is a solution. preferable. These raw materials are used and heat-treated in an inert gas atmosphere or a reducing gas atmosphere to obtain tungsten oxide fine particles and / or composite tungsten oxide fine particles having the above-mentioned particle diameter.

The composite tungsten oxide fine particles represented by the general formula MxWyOz containing the element M are the same as the tungsten compound starting material of the tungsten oxide fine particles represented by the general formula WyOz described above. A tungsten compound contained in the form of a simple substance or a compound is used as a starting material. Here, in order to produce a starting material in which each component is uniformly mixed at the molecular level, it is preferable to mix each material with a solution, and the tungsten compound starting material containing the element M is dissolved in a solvent such as water or an organic solvent. Preferably it is possible. Examples thereof include tungstate, chloride, nitrate, sulfate, oxalate, oxide, and the like containing element M, but are not limited to these and are preferably in the form of a solution.

Here, the heat treatment condition in the inert atmosphere is preferably 650 ° C. or higher. The starting material heat-treated at 650 ° C. or higher has sufficient coloring power and is efficient as infrared shielding fine particles. As the inert gas, an inert gas such as Ar or N ₂ is preferably used. As the heat treatment conditions in the reducing atmosphere, first, the starting material is heat-treated at 100 to 650 ° C. in a reducing gas atmosphere, and then heat-treated at a temperature of 650 to 1200 ° C. in an inert gas atmosphere. . The reducing gas at this time is not particularly limited, but H ₂ is preferable. When H ₂ is used as the reducing gas, the volume ratio of H ₂ is preferably 0.1% or more, more preferably 2% or more, as the composition of the reducing atmosphere. If it is 0.1% or more, the reduction can proceed efficiently.

The raw material powder reduced with hydrogen contains a magnetic phase, exhibits good infrared shielding properties, and can be used as infrared shielding particles in this state. However, since hydrogen contained in tungsten oxide is unstable, application may be limited in terms of weather resistance. Therefore, a more stable infrared shielding fine particle can be obtained by heat-treating the tungsten oxide compound containing hydrogen at 650 ° C. or higher in an inert atmosphere. The atmosphere during the heat treatment at 650 ° C. or higher is not particularly limited, but N ₂ and Ar are preferable from an industrial viewpoint. By the heat treatment at 650 ° C. or higher, a Magneli phase is obtained in the infrared shielding fine particles, and the weather resistance is improved.

The composite tungsten oxide fine particles of the present invention are preferably surface-treated with a coupling agent such as a silane coupling agent, a titanate coupling agent, or an aluminum coupling agent. Silane coupling agents are preferred. Thereby, affinity with binders, such as an intermediate | middle layer, a hard-coat layer, and a heat ray cut layer, becomes favorable, and various physical properties improve other than transparency and heat ray cut property.

Examples of silane coupling agents include γ-chloropropylmethoxysilane, vinylethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxy Silane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, vinyltrichlorosilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β Examples include-(aminoethyl) -γ-aminopropyltrimethoxysilane and trimethoxyacrylsilane. Vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, and trimethoxyacrylsilane are preferred. These silane coupling agents may be used alone or in combination of two or more. The content of the above compound is preferably 5 to 20 parts by mass with respect to 100 parts by mass of the fine particles.

(Composite) tungsten oxide fine particles are generally commercially available in the form of a dispersion (particularly an aqueous dispersion) as described above.

As the pressure-sensitive adhesive (adhesive resin) having an acidic group constituting the near-infrared shielding layer of the present invention, any pressure-sensitive adhesive having an acidic group can be used. Examples of the acidic group include a carboxyl group, a sulfo group, a sulfino group, a phosphoric acid group, a phosphonic acid group, and a sulfuric acid group. A carboxyl group and a sulfo group are preferable, and a carboxyl group is particularly preferable. It is easy to obtain a good dispersion state of the (composite) tungsten oxide fine particles. The acidic group should have an acid group in the adhesive resin so that the acid value of the adhesive is generally 0.5 KOH mg / g or more, preferably 2 to 50 KOH mg / g, particularly preferably 2 to 20 KOH mg / g. Is appropriate.

As the type of the adhesive resin, any resin having an acidic group may be used, and examples thereof include synthetic resins such as acrylic resin, polyester resin, urethane resin, epoxy resin, and silicon resin. These resins are preferably used in combination with a curing agent.

The pressure-sensitive adhesive having an acidic group constituting the near-infrared shielding layer is preferably an acrylic resin-based pressure-sensitive adhesive.

When the near-infrared shield of the present invention has a neon cut layer, examples of the resin used for the neon cut layer include synthetic resins such as acrylic resin, polyester resin, urethane resin, epoxy resin, and silicon resin. These resins are also preferably used in combination with a curing agent. The resin used for the neon cut layer preferably has adhesiveness, and an acrylic resin (particularly an acrylic resin-based adhesive) is preferable from such a viewpoint.

Examples of the structural component (monomer) of the acrylic resin suitably used for the near-infrared shielding layer and the neon cut layer include the following compounds.

Preferred examples of (meth) acrylic acid alkyl esters; alkyl groups having 1 to 12 carbon atoms which may be branched, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth ) Acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) ) Acrylate, dodecyl (meth) acrylate, lauryl (meth) acrylate ((meth) acrylate means both acrylate and methacrylate). In particular, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate are preferable.

Particularly preferred examples of the (meth) acrylic acid alkoxyalkyl ester include methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate.

Preferred examples of aromatic ring-containing monomers (copolymerizable compounds containing an aromatic group in the molecular structure) include: phenyl acrylate, phenoxyethyl (meth) acrylate, benzyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, ethylene Examples thereof include oxide-modified nonylphenol (meth) acrylate, hydroxyethylated β-naphthol acrylate, biphenyl (meth) acrylate, styrene, vinyltoluene, α-methylstyrene, and the like. In particular, phenyl acrylate, phenoxyethyl (meth) acrylate, benzyl (meth) acrylate, and phenoxydiethylene glycol (meth) acrylate are preferable.

Examples of hydroxyl-containing monomers include: 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) ) Acrylate, 1,4-cyclohexanedimethanol mono (meth) acrylate, chloro-2-hydroxypropyl acrylate, diethylene glycol mono (meth) acrylate, allyl alcohol and the like. In particular, 2-hydroxyethyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate are preferable.

Further, preferred examples of the monomer having a carboxyl group in the molecule include (meth) acrylic acid, 2-carboxyethyl (meth) acrylate, 3-carboxypropyl (meth) acrylate, 4-carboxybutyl (meth) acrylate, itacon Examples thereof include acid, crotonic acid, maleic acid, fumaric acid and maleic anhydride. In particular, (meth) acrylic acid is preferred.

Also, preferred examples of the amino group-containing monomer include aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, vinyl pyridine and the like. In particular, dimethylaminoethyl (meth) acrylate is preferable.

The monomer component is appropriately employed in accordance with the desired physical properties, but in the present invention, it is preferable to use a monomer having a carboxyl group for the acrylic resin of the near-infrared shielding layer.

The blending amount of the monomer mixture of the acrylic resin of the present invention is preferably (meth) acrylic acid alkyl ester and / or (meth) acrylic acid alkoxyalkyl ester: 4.5 to 89% by mass (particularly 22.7 to 69% by mass). %), Aromatic ring-containing monomer 10 to 85 mass% (especially 30 to 70 mass%), hydroxyl group-containing monomer: 1 to 10 mass% (especially 0.05 to 0.5 mass%), monomer having a carboxyl group: as appropriate Amino group-containing monomer: Appropriate.

The blending amount of the monomer mixture of the acrylic resin of the preferred near-infrared shielding layer is (meth) acrylic acid alkyl ester and / or (meth) acrylic acid alkoxyalkyl ester: 4.5 to 89% by mass (particularly 22.7 to 69% by mass), aromatic ring-containing monomer 10 to 85% by mass (particularly 30 to 70% by mass), hydroxyl group-containing monomer: 1 to 10% by mass (particularly 0.05 to 0.5% by mass), a monomer having a carboxyl group : 0.05 to 10% by mass (particularly 0.05 to 5% by mass), and amino group-containing monomer 0 to 0.5% by mass (particularly 0 to 0.3% by mass).

In the monomer mixture, other monomers may be mixed as necessary. Examples of other monomers include epoxy group-containing (meth) acrylates such as glycidyl (meth) acrylate; acetoacetyl group-containing (meth) acrylates such as acetoacetoxyethyl (meth) acrylate; vinyl acetate, vinyl chloride and ( And (meth) acrylonitrile. The mixing ratio of other monomers can be included at a ratio of 0 to 10% by mass.

The acrylic resin can be produced by a conventionally known polymerization method such as a solution polymerization method, a bulk polymerization method, an emulsion polymerization method and a suspension polymerization method, but does not contain a polymerization stabilizer such as an emulsifier or a suspending agent. What was manufactured by the polymerization method and the block polymerization method is preferable. The acrylic polymer has a weight average molecular weight (Mw) by gel permeation chromatography (GPC) of from 800,000 to 1,600,000, preferably from 800,000 to 1,500,000. If the Mw is less than 800,000, the cohesive strength of the pressure-sensitive adhesive is not sufficient even when the curing agent is blended in a suitable range, and foaming tends to occur under high temperature conditions, exceeding 1.6 million. And the stress relaxation property of an adhesive tends to fall. The ratio (Mw / Mn) of the weight average molecular weight to the number average molecular weight (Mn) is preferably 10-50. Further, it is preferably 20 to 50. If the ratio (Mw / Mn) becomes too large, the low molecular weight polymer increases and foaming tends to occur. Conversely, if the ratio (Mw / Mn) becomes too small, the stress relaxation property tends to decrease.

The acrylic resin (adhesive) is preferably used together with a curing agent. Examples of the curing agent include an epoxy compound-based crosslinking agent, an isocyanate compound-based crosslinking agent, a metal chelate compound-based crosslinking agent, an aziridine compound-based crosslinking agent, and an amino resin-based crosslinking agent. Among them, an epoxy compound-based crosslinking agent having two or more epoxy groups in the molecule, an isocyanate compound-based crosslinking agent having two or more isocyanate groups in the molecule, and an aziridine compound-based crosslinking agent are preferable. A crosslinking agent is preferred.

Examples of the epoxy compound-based crosslinking agent having two or more epoxy groups in the molecule include 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ′, N′-tetraglycyl-m- Xylylenediamine, N, N, N ′, N′-tetraglycidylaminophenylmethane, triglycidyl isocyanurate, mN, N-diglycidylaminophenylglycidyl ether, N, N-diglycidyltoluidine, N, N -Compounds having two or more epoxy groups such as diglycidyl aniline, pentaerythritol polyglycidyl ether, 1,6-hexanediol diglycidyl ether are preferred.

Examples of isocyanate compounds include isocyanate monomers such as tolylene diisocyanate, chlorophenylene diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, and the like. Isocyanate compounds obtained by adding these isocyanate monomers with trimethylolpropane, isocyanurates, burette type compounds, and urethane prepolymer type products such as polyether polyols, polyester polyols, acrylic polyols, polybutadiene polyols, polyisoprene polyols, etc. An isocyanate etc. can be mentioned.

Further, examples of the aziridine compound-based crosslinking agent include trimethylolpropane tri-β-aziridinylpropionate, trimethylolpropane tri-β- (2-methylaziridine) propionate, tetramethylolmethanetri-β-aziridinini. Examples include lupropionate and triethylenemelamine.

The blending amount of the crosslinking agent is preferably 0.0001 to 2.0 parts by weight with respect to 100 parts by weight of the acrylic resin.

The pressure-sensitive adhesive composition containing an acrylic resin preferably used in the present invention is an ultraviolet absorber, an antioxidant, an antiseptic and an antifungal agent as long as the transparency, visibility and the effects of the present invention are not impaired. , Tackifier resins, plasticizers, antifoaming agents, wettability adjusting agents and the like may be blended.

The near-infrared shielding layer is generally a layer mainly composed of the above tungsten oxide or composite tungsten oxide and a resin having an acidic group (preferably the above acrylic resin). The near-infrared shielding layer is obtained, for example, by coating, drying, and curing, if necessary, a coating solution containing the above (composite) tungsten oxide and a binder resin. Alternatively, it can also be obtained by applying a coating liquid containing the above (composite) tungsten oxide and a binder resin and simply drying it. When used as a film, it is generally a near infrared cut film, for example, a film containing (composite) tungsten oxide.

In addition to the (composite) tungsten oxide, a dye may be used if necessary. The dye generally has an absorption maximum at a wavelength of 800 to 1200 nm. Examples include phthalocyanine dyes, metal complex dyes, nickel dithiolene complex dyes, cyanine dyes, squarylium dyes, polymethine dyes, Examples thereof include azomethine dyes, azo dyes, polyazo dyes, diimonium dyes, aminium dyes, and anthraquinone dyes, and cyanine dyes, phthalocyanine dyes, and diimonium dyes are particularly preferable. These dyes can be used alone or in combination. The near-infrared shielding layer is preferably an adhesive layer, and examples of the adhesive resin include thermoplastic resins such as acrylic resins.

The near-infrared shielding layer preferably contains the above (composite) tungsten oxide in an amount of 0.1 to 20 parts by weight, more preferably 1 to 20 parts by weight, and particularly 1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The thickness of the near infrared shielding layer is generally 1 to 50 μm, preferably 5 to 50 μm.

In the present invention, a neon cut layer is provided together with a near-infrared shielding layer. Alternatively, the near-infrared shielding layer may contain a neon cut pigment (a pigment capable of imparting a neon emission absorption function) to have a neon emission absorption function.

As the neon cut dye, a dye having a maximum absorption in the wavelength range of 560 to 610 nm is particularly preferably used. According to the study by the present inventors, when the dye that cuts off the light emission derived from neon gas and the (composite) tungsten oxide are used in combination, the near infrared blocking function and the neon cutting function can be compatible at a high level, The near-infrared shielding property and durability of the infrared shielding body can be further improved. In addition, since the light derived from unnecessary neon gas is effectively cut, it is possible to improve the visibility of a display image such as a PDP and to remarkably prevent malfunction of surrounding electronic devices.

Examples of the dye {neon cut dye (neon emission selective absorption dye)} having maximum absorption in the wavelength range of 560 to 610 nm of the present invention include cyanine dyes, squarylium dyes, anthraquinone dyes, phthalocyanine dyes, polymethine dyes And polyazo dyes, azulenium dyes, diphenylmethane dyes, triphenylmethane dyes, and dyes having a polyphyllin ring structure. A dye having a porphine ring structure is preferred (particularly a structure in which a porphine ring is coordinated to a metal such as Fe or Mg). Examples of the dye having a porphyrin ring structure are commercially available from Yamada Chemical Co., Ltd. under trade names such as TAP-2, TAP-18, and TAP-45. Such a selective absorption dye is required to have a selective absorption of neon emission at around 585 nm and a small absorption at other visible light wavelengths. Therefore, the absorption maximum wavelength is 560 to 610 nm, and the absorption spectrum half width is small. What is 40 nm or less is preferable. The maximum absorption can be measured using, for example, a spectrophotometer UV3100PC (manufactured by Shimadzu Corporation).

Further, as long as optical properties are not greatly affected, coloring pigments, ultraviolet absorbers, antioxidants and the like may be further added.

The neon cut layer is generally a layer mainly composed of the neon cut dye and a binder resin (preferably the acrylic resin). The neon cut layer is obtained, for example, by applying a coating solution containing the above neon cut and binder resin, and if necessary, drying and curing. Alternatively, it can also be obtained by coating a coating liquid containing the neon cut and the binder resin, and simply drying.

The layer containing the neon cut pigment (near infrared shielding layer, near infrared shielding layer with neon cut function) is 0.1 to 20 parts by mass of neon cut pigment with respect to 100 parts by mass of binder resin (resin for adhesive). Further, it is preferable to contain 1 to 20 parts by mass, particularly 1 to 10 parts by mass. The thickness of such a layer is generally 1 to 50 μm, preferably 5 to 50 μm, particularly preferably 10 to 50 μm.

However, in the case of a neon cut layer, the neon cut dye is preferably contained in an amount of 0.1 to 5 parts by mass, and more preferably 0.1 to 2 parts by mass with respect to 100 parts by mass of the binder resin (adhesive resin). The thickness of the layer is generally 1 to 20 μm, preferably 1 to 10 μm.

The above-mentioned or normal pressure-sensitive adhesive layer is mainly a layer for adhering the optical film of the present invention to a display, and any resin can be used as long as it has an adhesive function. For example, acrylic adhesives, rubber adhesives, thermoplastic elastomers (TPE) such as SEBS (styrene / ethylene / butylene / styrene) and SBS (styrene / butadiene / styrene), which are formed from butyl acrylate, are the main components. TPE-based pressure-sensitive adhesives and adhesives can also be used.

The layer thickness is generally preferably 5 to 500 μm, particularly preferably 10 to 100 μm. The near-infrared shield can be equipped by generally pressing the pressure-sensitive adhesive layer on a glass plate of a display.

As the near-infrared absorption characteristics of the near-infrared shield of the present invention, the minimum transmittance in the near-infrared wavelength range of 800 to 1100 nm is preferably 30% or less, particularly 20% or less. preferable. As a result, there is an effect of reducing the transmittance in the wavelength region where malfunction of a peripheral device remote controller or the like is pointed out. In particular, the near-infrared shield has a minimum value of luminous transmittance of visible light in the wavelength range of 560 to 610 nm, 80% or less, more preferably 60% or less, particularly 40% or less in the wavelength range. In addition to the above effects, the orange color having a peak at 560 to 610 nm is a cause of deteriorating the color reproducibility, so it has the effect of absorbing the orange wavelength, thereby improving the redness and improving the color The reproducibility is improved.

Further, as described above, it is preferable for the light transmitted through the L ^* a ^* b ^* display system of the near-infrared shielding material b ^* is -15 or more.

When two transparent substrates are used in the present invention, these adhesions (adhesive layer) may be, for example, ethylene-vinyl acetate copolymer, ethylene-methyl acrylate copolymer, acrylic resin (eg, ethylene- ( (Meth) acrylic acid copolymer, ethylene-ethyl (meth) acrylate copolymer, ethylene- (meth) methyl acrylate copolymer, metal ion crosslinked ethylene- (meth) acrylic acid copolymer), partially saponified ethylene -Ethylene copolymers such as vinyl acetate copolymer, carboxylated ethylene-vinyl acetate copolymer, ethylene- (meth) acryl-maleic anhydride copolymer, ethylene-vinyl acetate- (meth) acrylate copolymer ("(Meth) acryl" indicates "acryl or methacryl"). In addition, polyvinyl butyral (PVB) resin, epoxy resin, phenol resin, silicon resin, polyester resin, urethane resin, rubber adhesive, thermoplastic elastomers such as SEBS and SBS can be used, but good adhesion Acrylic resin adhesives and epoxy resins are easily obtained.

The layer thickness is preferably in the range of 10 to 100 μm. The near-infrared shield can be equipped by generally pressing the pressure-sensitive adhesive layer on a glass plate of a display.

When EVA is also used as the material for the pressure-sensitive adhesive layer, EVA having a vinyl acetate content of 5 to 50% by mass, preferably 15 to 40% by mass is used. When the vinyl acetate content is less than 5% by mass, there is a problem in transparency, and when it exceeds 40% by mass, the mechanical properties are remarkably deteriorated and the film formation becomes difficult and the films tend to block each other.

As the crosslinking agent, in the case of heat crosslinking, an organic peroxide is suitable, and is selected in consideration of sheet processing temperature, crosslinking temperature, storage stability, and the like. The organic peroxide is usually kneaded with EVA using an extruder, a roll mill or the like, but may be dissolved in an organic solvent, a plasticizer, a vinyl monomer or the like and added to the EVA film by an impregnation method.

The pressure-sensitive adhesive layer for the above-mentioned adhesion is, for example, a mixture of EVA and the above-mentioned additives, kneaded with an extruder, roll, etc., and then formed into a predetermined shape by a film forming method such as calendar, roll, T-die extrusion, inflation, etc. It is manufactured by forming a sheet.

A protective layer may be provided on the antireflection layer. The protective layer is preferably formed in the same manner as the hard coat layer.

As the material of the release sheet provided on the pressure-sensitive adhesive layer, a transparent polymer having a glass transition temperature of 50 ° C. or higher is preferable. Examples of such a material include polyesters such as polyethylene terephthalate, polycyclohexylene terephthalate, and polyethylene naphthalate. In addition to polyamide resins such as resin, nylon 46, modified nylon 6T, nylon MXD6, polyphthalamide, ketone resins such as polyphenylene sulfide and polythioether sulfone, and sulfone resins such as polysulfone and polyether sulfone. Mainly composed of polymers such as ether nitrile, polyarylate, polyetherimide, polyamideimide, polycarbonate, polymethyl methacrylate, triacetyl cellulose, polystyrene, polyvinyl chloride Resin can be used. Of these, polycarbonate, polymethyl methacrylate, polyvinyl chloride, polystyrene, and polyethylene terephthalate can be suitably used. The thickness is preferably 10 to 200 μm, particularly preferably 30 to 100 μm.

The near-infrared shield of the present invention is preferably used as an optical filter for display. FIG. 9 shows an example of a state in which the near-infrared shield (display optical filter) of the present invention is attached to the image display surface of a plasma display panel which is a kind of display. An optical filter is bonded to the surface of the display surface of the display panel 90 via a near-infrared shielding layer 93 having adhesiveness. That is, a mesh-like conductive layer 94, a hard coat layer 92A, and a low refractive index layer 92B are provided in this order on one surface of the transparent substrate 91, and a near-infrared shielding layer 93 is provided on the other surface of the transparent substrate 91. The optical filter is provided on the display surface. The mesh-like conductive layer 94 'is exposed at the edge (side edge) of the filter (for example, obtained by removing each layer at the end with a laser). The exposed mesh-like conductive layer 94 ′ is brought into contact with a metal cover 99 provided around the plasma display panel 90 through shield fingers (plate spring-like metal parts) 98. A conductive gasket or the like may be used instead of the shield finger (plate spring-like metal part). As a result, the optical filter and the metal cover 99 are electrically connected, and grounding is achieved. The metal cover 99 may be a metal frame or a frame. As is clear from FIG. 9, the mesh-shaped conductive layer 93 faces the viewer side.

Since the PDP display of the present invention generally uses a plastic film as a transparent substrate, the near-infrared shield of the present invention can be directly bonded to the surface of the glass plate, as described above. When one substrate is used, it can contribute to reducing the weight, thickness and cost of the PDP itself. Compared with the case where a front plate made of a transparent molded body is installed on the front side of the PDP, an air layer having a low refractive index can be eliminated between the PDP and the PDP filter, so that visible light reflection due to interface reflection can be achieved. Problems such as an increase in rate and double reflection can be solved, and the visibility of the PDP can be further improved.
The near-infrared shielding body of the present invention has at least the near-infrared shielding layer described above, and may further have a functional layer such as a transparent substrate, an adhesive layer, or an antireflection layer, if necessary. good.

EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not limited to a following example.
[Example 1]
<Preparation of optical filter for display>
(Preparation of film with near-infrared shielding layer)
On a PET film (thickness: 188 μm, A4300; manufactured by Toyobo Co., Ltd.), a coating solution for forming an adhesive near infrared shielding layer having the following composition was applied using an applicator so that the thickness would be 25 μm after drying. And dried in an oven at 80 ° C. for 2 minutes. This produced the optical filter for displays which has an adhesive near-infrared shielding layer (thickness 25 micrometers) on a laminated body.
(Composition of the coating liquid for forming the adhesive near-infrared shielding layer)
Acrylic resin-based adhesive (trade name: SK Dyne 1501BS4, manufactured by Soken Chemical Co., Ltd., acid value: 4.7 KOHmg / g, solid content: 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name: L-45E , Manufactured by Soken Chemical Co., Ltd.)
1 part by mass Cs _0.33 WO ₃
(Average particle size 80 nm, solid content 20% by mass, MIBK solution) 5 parts by mass [Comparative Example 1]
<Preparation of optical filter for display>
An optical filter for display was obtained in the same manner as in Example 1 except that the following coating liquid for forming an adhesive near-infrared shielding layer was used.
(Composition of the coating liquid for forming the adhesive near-infrared shielding layer)
Acrylic adhesive (trade name SK Dyne 1811L, manufactured by Soken Chemical Co., Ltd.,
Acid value: 0.0 KOH mg / g, solid content 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name L-45, manufactured by Soken Chemical Co., Ltd.)
1 part by mass Cs _0.33 WO ₃
(Average particle size 80 nm, solid content 20% by mass, MIBK solution) 5 parts by mass In addition, when an acrylic adhesive and Cs _0.33 WO ₃ dispersion were mixed, they became cloudy but were used as they were to produce an optical filter for display. did.

[Example 2]
<Preparation of film with mesh conductive layer>
A copper foil was laminated on one surface of a PET film (thickness: 100 μm) via an adhesive layer, and then the copper foil was etched by a photolithography method. Thereby, a film having a mesh-like conductive layer (average height 10 μm, average width 20 μm, pitch 250 μm, aperture ratio 85%) was obtained.

<Preparation of substrate with near-infrared shielding layer>
On the other surface of the PET film, a coating solution for forming an adhesive near-infrared shielding layer having the following composition was applied using an applicator so as to have a thickness of 25 μm after drying, and in an oven at 80 ° C. And dried for 2 minutes. Thus, the PET film having a mesh-like conductive layer laminated on one surface via an adhesive layer and an adhesive near-infrared shielding layer (thickness 25 μm) on the other surface (FIG. 4). ) Was produced.
(Coating liquid for forming adhesive near-infrared shielding layer)
Acrylic resin-based adhesive (trade name: SK Dyne 1501BS4, manufactured by Soken Chemical Co., Ltd., acid value: 4.7 KOHmg / g, solid content: 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name: L-45E 1 part by weight Cs _0.33 WO ₃ manufactured by Soken Chemical Co., Ltd.
(Average particle size 80 nm, solid content 20 mass%, MIBK solution) 5 mass parts <Preparation of near-infrared shield>
On the float glass (thickness 2.5 mm), the upper PET film was placed so that the near-infrared shielding layer and the float glass face each other, and these were pressure-bonded. This obtained the near-infrared shield (FIG. 4).

[Example 3]
<Preparation of film with mesh conductive layer>
In the same manner as in Example 2, a film having a mesh-like conductive layer (average height 10 μm, average width 20 μm, pitch 250 μm, aperture ratio 85%) was obtained.

<Preparation of substrate with near-infrared shielding layer>
An adhesive near-infrared shielding layer (thickness 25 μm) was produced in the same manner as in Example 2, except that the adhesive liquid for forming an adhesive near-infrared shielding layer was applied onto the mesh-shaped conductive layer produced above. . Thereby, the PET having a mesh-like conductive layer laminated on one surface via an adhesive layer, and an adhesive near-infrared shielding layer (thickness 25 μm) laminated on the mesh-like conductive layer A film (FIG. 5) was produced.

<Preparation of optical filter for display>
On the float glass (thickness 2.5 mm), the upper PET film was placed so that the near-infrared shielding layer and the float glass face each other, and these were pressure-bonded. This obtained the near-infrared shield (FIG. 5).

[Comparative Example 2]
In Example 2, an optical filter for display was obtained in the same manner except that the following coating liquid for forming an adhesive near-infrared shielding layer was used.
(Composition of the coating liquid for forming the adhesive near-infrared shielding layer)
Acrylic adhesive (trade name SK Dyne 1811L, manufactured by Soken Chemical Co., Ltd.,
Acid value: 0.0 KOH mg / g, solid content 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name L-45, manufactured by Soken Chemical Co., Ltd.)
1 part by mass Cs _0.33 WO ₃
(Average particle size 80 nm, solid content 20% by mass, MIBK solution) 5 parts by mass In addition, when an acrylic adhesive and Cs _0.33 WO ₃ dispersion were mixed, they became cloudy but were used as they were to produce an optical filter for display. did.
[Evaluation of optical filter for display]
For the optical filters for display produced in Examples 1 to 3 and Comparative Examples 1 and 2, the following evaluations (1) to (3) were performed. The results are shown in Tables 1 and 2.
(1) Luminous transmittance The luminous transmittance (JIS-Z-8105-1982) of the optical filter for display was measured with a spectrophotometer UV3100PC (manufactured by Shimadzu Corporation).
(2) Minimum value of transmittance of near infrared light of 800 to 1100 nm For the display optical filter, the minimum value of transmittance of near infrared light was measured with a spectrophotometer UV3100PC (manufactured by Shimadzu Corporation).
(3) Haze The haze value of the optical filter for display was measured using a fully automatic direct reading haze computer HGM-2DP (manufactured by Suga Test Instruments Co., Ltd.) according to the method of JIS-K-7105 (1981).

The optical filter for display obtained in Example 1 has a high total light transmittance, low haze, and excellent transparency. On the other hand, since the minimum value of the transmittance of 800 to 1100 nm is low, an effective near-infrared cut is achieved. Indicates the function. This is considered because Cs _0.33 WO ₃ particles are finely and uniformly dispersed. On the other hand, the optical filter for display obtained in Comparative Example 1 does not have a high total light transmittance and has a high haze, so that the transparency is not sufficient, and the minimum value of 800-1100 nm transmittance is high. The cutting function is not satisfactory. This is considered because Cs _0.33 WO ₃ particles are not uniformly dispersed. Similar results were obtained in Examples 2 and 3 and Comparative Example 2.
[Example 4]
<Preparation of film with antireflection layer and near infrared shielding layer>
On a PET film (thickness: 188 μm, A4300; manufactured by Toyobo Co., Ltd.), a hard coat layer forming coating solution (solid content concentration: 40 mass%; viscosity: 25 ° C., 100 cP) having the following composition was used with a bar coater. The film was applied to a thickness of about 12 μm, dried in an oven at 80 ° C. for 1 minute, and then cured by irradiating with an ultraviolet ray with an integrated light quantity of 1000 mJ / cm ² . This produced the optical filter for displays which has a hard-coat layer (thickness 6.9 micrometers) on a laminated body.
(Composition of hard coat layer forming coating solution)
Dipentaerythritol hexaacrylate 100 parts by weight TiO ₂ particles (average particle size 0.1 μm) 10 parts by weight Polymerization initiator (Irquagua 184, manufactured by Ciba Specialty Chemicals) 7 parts by weight Isopropyl alcohol (IPA) 50 parts by weight Methyl ethyl ketone (MEK) 100 parts by mass Cyclohexanone (CAN) 25 parts by mass Next, the following composition:
(Composition of coating solution for forming low refractive index layer)
Opstar JN-7212 (manufactured by Nippon Synthetic Rubber Co., Ltd.) 100 parts by weight Methyl ethyl ketone 117 parts by weight Methyl isobutyl ketone 117 parts by weight was applied onto the hard coat layer using a bar coater, 120 The film was dried in an oven at 30 ° C. for 30 minutes and cured by ultraviolet irradiation. Thereby, a low refractive index layer (refractive index 1.40) having a thickness of 90 nm was formed on the hard coat layer.

On the back surface of the PET film provided with an antireflection layer comprising a hard coat layer and a low refractive index layer, the following composition:
(Coating solution for forming near-infrared shielding layer with neon cut function)
Acrylic resin-based adhesive (trade name: SK Dyne 1501BS4, manufactured by Soken Chemical Co., Ltd., acid value: 4.7 KOHmg / g, solid content: 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name: L-45E 1 part by weight Cs _0.33 WO ₃ manufactured by Soken Chemical Co., Ltd.
(Average particle size 80 nm, solid content 20% by mass, MIBK solution) 5 parts by mass Neon cut dye (maximum absorption at 560 to 610 nm: 592 nm)
A coating solution obtained by mixing 0.5 parts by mass of a trade name TAP-2 (manufactured by Yamada Chemical Co., Ltd.) was applied using an applicator to a thickness of 25 μm after drying, Dry in oven for 2 minutes. This produced the optical filter for displays which has an adhesive near-infrared shielding layer with a neon cut function (thickness 25 micrometers) on a laminated body.

This obtained the film which has an antireflection layer and a near-infrared shielding layer with a neon cut function.
<Preparation of mesh conductive layer film with adhesive layer>
On a PET film (thickness 100 μm, A4303; manufactured by Toyobo Co., Ltd.), a mesh conductive layer film (opening ratio 85%) made of copper having an average height of 3.3 μm and a pitch of 165 μm was prepared.

On the back surface of the mesh conductive layer film, the following composition:
(Coating liquid for forming adhesive layer)
Acrylic resin adhesive (trade name SK Dyne 1811L, manufactured by Soken Chemical Co., Ltd., solid content 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name L-45, manufactured by Soken Chemical Co., Ltd.) 1 The coating solution obtained by mixing the mass parts was applied using an applicator and dried in an oven at 80 ° C. for 5 minutes. This formed the 25-micrometer-thick adhesive layer in the back surface of a mesh-like conductive layer film.
<Preparation of optical filter for display>
The mesh-like conductive layer film with the pressure-sensitive adhesive layer obtained above is placed on the glass plate so that the pressure-sensitive adhesive layer and the glass plate surface face each other, and further reflected on the conductive layer of the mesh-like conductive layer film. The film with a near-infrared shielding layer with a prevention layer and a neon cut function was placed so that the conductive layer and the near-infrared shielding layer were in contact, and these were pressure-bonded. Thereby, an optical filter for display was obtained.
[Example 5]
<Preparation of film with antireflection layer and near infrared shielding layer>
On the back surface of the PET film provided with an antireflection layer comprising a hard coat layer and a low refractive index layer obtained in the same manner as in Example 4, the following composition:
(Coating solution for neon cut layer formation)
The following formulation:
Polymethyl methacrylate (solid content: 100% by mass) 30 parts by mass Methyl ethyl ketone 152 parts by mass Methyl isobutyl ketone 182 parts by mass Neon cut dye (maximum absorption at 560 to 610 nm: 592 nm
A coating solution obtained by mixing 0.3 part by mass of a trade name TAP-2 (manufactured by Yamada Chemical Co., Ltd.) was applied using a bar coater to a thickness of 5 μm after drying, and an oven at 80 ° C. The mixture was dried for 2 minutes to form a neon cut layer.
(Near-infrared shielding layer forming coating solution)
The following formulation:
Acrylic resin-based adhesive (trade name: SK Dyne 1501BS4, manufactured by Soken Chemical Co., Ltd., acid value: 4.7 KOHmg / g, solid content: 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name: L-45E 1 part by weight Cs _0.33 WO ₃ manufactured by Soken Chemical Co., Ltd.
(Average particle size 80 nm, solid content 20% by mass, MIBK solution) A coating solution obtained by mixing 5 parts by mass was coated on the neon cut layer using an applicator so that the thickness after drying was 25 μm. And dried in an oven at 80 ° C. for 2 minutes.

Thereby, an optical filter for display having an adhesive neon cut layer and a near-infrared shielding layer (thickness 25 μm) on the laminate was produced.

This obtained the film which has an antireflection layer, a neon cut layer, and a near-infrared shielding layer.
<Preparation of mesh conductive layer film with adhesive layer>
On a PET film (thickness 100 μm, A4303; manufactured by Toyobo Co., Ltd.), a mesh conductive layer film (opening ratio 85%) made of copper having an average height of 3.3 μm and a pitch of 165 μm was prepared.

On the back surface of the mesh conductive layer film, the following composition:
(Coating liquid for forming adhesive layer)
Acrylic resin adhesive (trade name SK Dyne 1811L, manufactured by Soken Chemical Co., Ltd., solid content 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name L-45, manufactured by Soken Chemical Co., Ltd.) 1 The coating solution obtained by mixing the mass parts was applied using a bar coater and dried in an oven at 80 ° C. for 5 minutes. This formed the 25-micrometer-thick adhesive layer in the back surface of a mesh-like conductive layer film.
<Preparation of optical filter for display>
The mesh-like conductive layer film with the pressure-sensitive adhesive layer obtained above is placed on the glass plate so that the pressure-sensitive adhesive layer and the glass plate surface face each other, and further reflected on the conductive layer of the mesh-like conductive layer film. The prevention layer and the film with a near-infrared shielding layer were placed so that the conductive layer and the near-infrared shielding layer were in contact, and these were pressure-bonded.

Thereby, an optical filter for display (see FIG. 7) was obtained.
[Comparative Example 3]
In Example 4, an optical filter for display was obtained in the same manner except that the following coating liquid for forming a near-infrared shielding layer with a neon cut function was used.
(Coating solution for forming near-infrared shielding layer with neon cut function)
Acrylic resin adhesive (trade name: SK Dyne 1811L, manufactured by Soken Chemical Co., Ltd., acid value: 0.0 KOHmg / g, solid content: 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name: L-45 1 part by weight Cs _0.33 WO ₃ manufactured by Soken Chemical Co., Ltd.
(Average particle size 80 nm, solid content 20% by mass, MIBK solution) 5 parts by mass Neon cut dye (maximum absorption at 560 to 610 nm: 592 nm)
Product name TAP-2, manufactured by Yamada Chemical Co., Ltd.) 0.5 parts by mass [Example 6]
<Preparation of film with mesh conductive layer>
A copper foil was laminated on one surface of a PET film (thickness: 100 μm) via an adhesive layer, and then the copper foil was etched by a photolithography method. As a result, a PET film having a mesh-like conductive layer (average height 10 μm, average width 20 μm, pitch 250 μm, aperture ratio 85%) was obtained.

<Preparation of substrate with near-infrared shielding layer>
On the other surface of the PET film, a coating solution for forming a near-infrared shielding layer with a neon cut function having the following composition was applied using an applicator so as to have a thickness of 25 μm after drying. Dry in oven for 2 minutes. Thereby, it has a mesh-like conductive layer laminated on one surface via an adhesive layer, and has a sticky neon-cutting function near-infrared shielding layer (thickness 25 μm) on the other surface. A PET film (FIG. 6) was produced.
(Coating solution for forming near-infrared shielding layer with neon cut function)
Acrylic resin-based adhesive (trade name: SK Dyne 1501BS4, manufactured by Soken Chemical Co., Ltd., acid value: 4.7 KOH mg / g, solid content: 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name: L-45E 1 part by weight Cs _0.33 WO ₃ manufactured by Soken Chemical Co., Ltd.
(Average particle size 80 nm, solid content 20% by mass, MIBK solution) 5 parts by mass Neon cut dye (maximum absorption at 560 to 610 nm: 592 nm)
Product name TAP-2, manufactured by Yamada Chemical Co., Ltd.) 0.5 parts by mass <Preparation of optical filter for display>
On the float glass (thickness 2.5 mm), the upper PET film was placed so that the near-infrared shielding layer and the float glass face each other, and these were pressure-bonded. Thereby, an optical filter for display (see FIG. 4) was obtained.
[Example 7]
<Preparation of film with mesh conductive layer>
In the same manner as in Example 6, a film having a mesh-like conductive layer (average height 10 μm, average width 20 μm, pitch 250 μm, aperture ratio 85%) was obtained.

<Preparation of substrate with near-infrared shielding layer>
A near-infrared shielding layer with a neon-cut function (thickness 25 μm) was formed in the same manner as in Example 6 except that the adhesive near-infrared shielding layer forming coating solution was applied onto the mesh-shaped conductive layer prepared above. Produced. Thereby, a mesh-like conductive layer laminated on one surface via an adhesive layer, and a sticky near-infrared shielding layer with a neon cut function (thickness 25 μm) laminated on the mesh-like conductive layer The PET film having FIG.

<Preparation of optical filter for display>
On the float glass (thickness 2.5 mm), the upper PET film was placed so that the near-infrared shielding layer and the float glass face each other, and these were pressure-bonded. Thereby, an optical filter for display (see FIG. 5) was obtained.

[Comparative Example 4]
In Example 6, an optical filter for display was obtained in the same manner except that the following coating liquid for forming a near-infrared shielding layer with a neon cut function was used.
(Coating solution for forming near-infrared shielding layer with neon cut function)
Acrylic resin adhesive (trade name: SK Dyne 1811L, manufactured by Soken Chemical Co., Ltd., acid value: 0.0 KOHmg / g, solid content: 20% by mass, ethyl acetate solution) 100 parts by mass Isocyanate curing agent (trade name: L-45 1 part by weight Cs _0.33 WO ₃ manufactured by Soken Chemical Co., Ltd.
(Average particle size 80 nm, solid content 20% by mass, MIBK solution) 5 parts by mass Neon cut dye (maximum absorption at 560 to 610 nm: 592 nm)
Product name TAP-2, manufactured by Yamada Chemical Co., Ltd.) 0.5 parts by mass [evaluation of optical filter for display]
For the optical filters for display produced in Examples 4 to 7 and Comparative Examples 3 and 4, the following evaluations (4) to (6) were performed. The results are shown in Tables 3 and 4.
(4) Luminous transmittance The luminous transmittance (JIS-Z-8105-1982) of the optical filter for display was measured with a spectrophotometer UV3100PC (manufactured by Shimadzu Corporation).
(5) Minimum value with respect to luminous transmittance of visible light in the wavelength region of 560 to 610 nm For the optical filter for display, the luminous transmittance (definition JIS Z8105-1982) is spectrophotometer UV3100PC (manufactured by Shimadzu Corporation) ), The Y of the tristimulus value of the XYZ color system was calculated, and the luminous transmittance (Y) was obtained. The calculation method was performed with a C light source of 2 ° (JIS Z8722-2000).
(6) Minimum value of near-infrared light transmittance in the wavelength range of 800 to 1100 nm The minimum value of the near-infrared light transmittance was measured with a spectrophotometer UV3100PC (manufactured by Shimadzu Corporation).

The optical filters for displays obtained in Examples 4 and 5 have low visible transmittance of visible light of 560 to 610 nm, light from neon gas is sufficiently cut, and at the same time, the minimum transmittance of 800 to 1100 nm It also shows an excellent near-infrared cut function because of its low value. This can be said to be a remarkable effect of using Cs _0.33 WO ₃ and a neon cut dye at the same time. Similar results were obtained in Examples 6 and 7 and Comparative Example 4.

11, 21A, 21B, 31, 41A, 41B:

Transparent substrate

51A, 51B, 61, 71A, 71B, 81, 91:

Transparent substrate

12, 22, 32, 62, 72, 82:

Antireflection layer

13, 23, 33 43, 53, 63, 73, 83, 93: Near-

infrared shielding layer

64, 74, 84: Neon cut

layer

24, 34, 44, 54, 94: Conductive layer 75, 85: Conductive layer 25, 76: Adhesive Layers 46 and 56: Adhesive layer

Claims

A near-infrared shield comprising a tungsten oxide and / or a composite tungsten oxide and an adhesive having an acidic group.
The near-infrared shielding body according to claim 1, wherein the acid value of the pressure-sensitive adhesive is 0.5 KOHmg / g or more.
The near-infrared shield according to claim 1 or 2, wherein the adhesive is an acrylic resin-based adhesive.
The near-infrared shield according to any one of claims 1 to 3, wherein the acidic group of the pressure-sensitive adhesive is a carboxyl group.
The near-infrared shield according to any one of claims 1 to 4, further comprising a dye having a maximum absorption in a wavelength range of 560 to 610 nm.
6. The near-infrared shielding layer containing tungsten oxide and / or composite tungsten oxide, and a neon cut layer containing a dye having a maximum absorption in the wavelength range of 560 to 610 nm. Near-infrared shield.
6. The near-infrared shielding body according to claim 1, further comprising a near-infrared shielding layer containing tungsten oxide and / or composite tungsten oxide and a dye having a maximum absorption in a wavelength range of 560 to 610 nm.
A conductive layer and an antireflection layer are provided in this order on one surface of the substrate, and a near-infrared shielding layer is provided on the other surface of the substrate,
The near-infrared shielding body according to any one of claims 1 to 5, wherein the near-infrared shielding layer contains tungsten oxide and / or composite tungsten oxide and an adhesive having an acidic group.
The near-infrared shielding body according to claim 8, wherein the near-infrared shielding layer further contains a pigment having a maximum absorption in a wavelength range of 560 to 610 nm.
The near-infrared shield according to any one of claims 1 to 9, wherein the tungsten oxide and / or the composite tungsten oxide is in the form of fine particles.
The near-infrared shield according to claim 8, wherein the average particle diameter of the fine particles is 400 nm or less.
Tungsten oxide is represented by the general formula WyOz (where W is tungsten, O represents oxygen and 2.2 ≦ z / y ≦ 2.999), and the composite tungsten oxide is represented by the general formula MxWyOz. (However, M is H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au. Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re, Be One or more elements selected from Hf, Os, Bi, and I, W represents tungsten, O represents oxygen, and 0.001 ≦ x / y ≦ 1, 2.2 ≦ z / y ≦ 3 12. The vicinity of any one of claims 1 to 11 represented by External shield.
The near-infrared shielding body according to any one of claims 1 to 12, which is used as an optical filter for a display.
The near-infrared shield according to any one of claims 1 to 13, which is used as a filter for a plasma display panel.