JP2007144926A - Electroconductive anti-reflection laminate and display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electroconductive anti-reflection laminate which does not cause interfacial debonding, even when the numbers of times of reciprocation of steel wool are increased in the scratch resistance test using steel wool. <P>SOLUTION: The electroconductive anti-reflection laminate is composed at least of a hardcoat layer, a metallic thin film layer and a transparent thin film layer laminated on a substrate. The hard coat layer has a hardness of ≥4H under a load of 500 g in the pencil hardness test and show an elastic deformation (the load curve and unload curve are identical within a 20% deviation) at a depth of indentation of ≤50 nm in the indentation test specified by JIS K 5600. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a conductive antireflection laminate, and more particularly to a conductive antireflection laminate useful as an antireflection filter used on the front surface of an optical display device such as a flat panel display (FPD).

  Conventionally, an optical display device such as a CRT, a liquid crystal display device, or a plasma display panel (PDP) has a problem that it is difficult to recognize a display image due to reflection of external light on a display screen. In recent years, optical display devices have been increasingly taken not only indoors but also outdoors, and the deterioration of visibility due to the reflection of external light on the display screen has become a more serious problem.

  In order to reduce the reflection of external light, an antireflection laminate having a low reflectance over a wide range of wavelengths in the visible light region is provided on the front surface of the optical display device. In addition, by providing the antireflection laminate with conductivity, a conductive antireflection laminate having an antistatic function or an electromagnetic wave shielding function is provided.

  As an example of a conductive antireflection laminate, as a first example, in Patent Document 1, a transparent conductive oxide and a low refractive index are used in which a conductive material is imparted to a high refractive index layer using a transparent conductive oxide. Are described. As a second example, Patent Document 2 describes a laminate including a light-absorbing conductive layer and a low refractive index layer. As a third example, Patent Document 3 and Patent Document 4 describe a silver-based thin film and a conductive antireflection film made of a transparent oxide sandwiching the silver-based thin film.

  Among the antireflection laminates, the transparent conductive oxide of the high refractive index layer and the low refractive index alternating laminated film of the first example require four or more layers to obtain broadband antireflection performance. Since the total film thickness is also required to be 170 nm or more, there are problems in terms of productivity and cost. The laminated film composed of the light-absorbing conductive layer and the low refractive index layer in the second example has a small number of laminated films and a relatively thin film thickness, and has a broadband antireflection characteristic in the visible range. However, this is not a problem for CRT applications where the absorption is relatively large and the brightness of the display is bright. However, LCDs and PDPs in recent flat panel displays use light absorbing layers such as color filters and color adjustment filters because of their structure. It cannot be used from the viewpoint of luminance reduction.

In the conductive thin film laminate made of the transparent thin oxide sandwiching the silver thin film and the silver thin film in the third example, the metal thin film layer mainly composed of silver with the high refractive index transparent thin film layer is supported 3 Anti-reflection performance can be obtained by optimizing the optical constant (complex refractive index n-ik) and physical film thickness of each layer in a conductive thin film laminated layer of odd-numbered layers or more, but in the visible region. Since the anti-reflection band is relatively narrow and the reflected color is colored, it cannot be used on the display surface. Japanese Patent Application Laid-Open No. 11-64603 has a broadband antireflection performance and a transmittance of 80% or more, but it has a film thickness of 200 nm or more and cannot be used practically from the viewpoint of cost and mass productivity. The structure of a conductive antireflection laminate having a film thickness of 120 nm or less is non-patented as a structure of a conductive antireflection laminate that is excellent in cost and mass productivity in industry, and provides antireflection performance that is practically satisfactory. It is described in Document 1.
Japanese Patent Laid-Open No. 11-138777 Japanese Patent Laid-Open No. 09-73001 Japanese Patent Laid-Open No. 11-23804 JP-A-11-64603 Thin Solid Films 442 (2003) 153-157 J. et al. Non-Crystalline Solids 178 (1994) 245-249 Thin Solid Films 392 (2001) 289-293

  However, for example, in the configuration consisting of the silver-based thin film and the transparent oxide sandwiching the silver-based thin film described in Non-Patent Document 1, in the scratch resistance test with steel wool as the mechanical strength that is essential as the practicality of the display, There are problems such as occurrence of peeling and low mechanical strength.

  For example, in the configuration shown in FIG. 1, the peeling portion is peeled off at the interface between the high refractive index transparent thin film layer 4 a and the metal thin film layer 4 b mainly composed of silver. This is because conductive thin film stacks, in which high-refractive-index transparent thin film layers and metal thin film layers containing silver as a main component are alternately provided, are caused by migration of fine silver at high temperatures and high humidity, or by external stress. It seems that this phenomenon is similar to the phenomenon that peeling easily occurs at the interface (see Non-Patent Documents 2 and 3).

  This is because the adhesion between silver and the transparent oxide conductor is weak, and if the internal stress of the high refractive index transparent thin film layer adjacent to silver is large, the silver and the transparent oxide can be easily changed when shape change such as silver migration occurs. It is said that peeling occurs at the interface of the conductor. In the scratch resistance test, the abrasion resistance is tested while applying a load to the steel wool and reciprocating. The applied load is applied to the conductive thin film laminate layer as an external stress through the steel wool fibers. It seems that shape changes including the work, transparent base material, and hard coat occur, and the interfacial peeling occurs in the process of increasing the number of reciprocations of the steel wool, resulting in scratches (see FIG. 2).

  The present invention has been made to solve the above-mentioned problems, and the problem is that in the scratch resistance test using steel wool, the occurrence of interfacial delamination is suppressed even when the number of reciprocations of steel wool is increased. It is to provide a conductive antireflection laminate.

  The invention of claim 1 is a conductive antireflection laminate having a conductive thin film laminate layer formed by laminating a hard coat layer, a metal thin film layer, and a transparent thin film layer on at least a substrate, wherein the hard coat layer Is not less than 4H in the pencil hardness test of 500g load specified in JIS K 5600, and in the indentation test, the indentation depth is 50nm or less and the elastic deformation (the load curve and the unloading curve must be within 20%) A conductive antireflection laminate, which is a hard coat layer.

  The invention according to claim 2 is the conductive antireflection laminate according to claim 1, wherein the Young's modulus determined by an indentation hardness test of the hard coat layer is 4.5 GPa or more.

  The invention according to claim 3 is characterized in that the conductive thin film laminated layer is a high refractive index transparent thin film layer / a metal thin film layer / a high refractive index transparent thin film layer. It is a laminate.

  The invention according to claim 4 is the conductive antireflection laminate according to any one of claims 1 to 3, wherein the metal thin film layer is silver or an alloy containing silver.

  The invention according to claim 5 is the conductive antireflection laminate according to any one of claims 1 to 4, wherein a low refractive index transparent thin film layer is provided on the conductive thin film laminate layer. .

  The invention according to claim 6 is characterized in that the low refractive index transparent thin film layer has a laminated structure of a low density layer and a high density layer, and the high density layer is located on the outermost layer side. Antireflective laminate.

  The invention according to claim 7 is the conductive antireflection laminate according to claim 6, wherein the low refractive index layer transparent thin film has a multilayer structure in which low density layers and high density layers are alternately laminated. is there.

  The invention according to claim 8 is the conductive antireflective laminate according to claim 5, wherein the film density of the low refractive index transparent thin film layer is continuously changed.

  The invention according to claim 9 is the conductive antireflection laminate according to any one of claims 1 to 8, wherein an antifouling layer is provided on the uppermost layer.

  The invention according to claim 10 is characterized in that the film thickness excluding the base material and the hard coat layer of the conductive antireflection laminate is 110 nm or less in shape film thickness. A conductive antireflection laminate.

  An eleventh aspect of the invention is a display characterized in that the conductive antireflection laminate according to any one of the first to tenth aspects is provided on the front surface of the display.

  According to the present invention, in a conductive antireflection laminate having a conductive thin film laminate formed by laminating a hard coat layer, a metal thin film layer, and a transparent thin film layer on a substrate, the scratch resistance test using steel wool is performed. Even if the number of reciprocations of steel wool is increased, a conductive antireflection laminate in which occurrence of interface peeling is suppressed can be obtained.

Hereinafter, a conductive antireflection laminate according to the present invention will be described in detail with reference to the drawings.
The conductive antireflection laminate 1 shown in FIG. 4 includes a base material 2, a hard coat layer 3 provided on the base material 2, a conductive thin film laminate layer 4 provided on the hard coat layer 3, and a conductive property. The low refractive index transparent thin film layer 5 provided on the thin film laminated layer 4 and the antifouling layer 6 provided on the low refractive index transparent thin film layer 5 are roughly constituted.

<Base material>
Examples of the substrate 2 of the present invention include a transparent inorganic compound molded product or an organic compound molded product, and an organic compound is preferred from the viewpoint of flexibility and light weight, and above all, processability. The shape of the molded product is not particularly limited as long as the surface is smooth, but a roll shape or the like is preferable. Further, the substrate may be a homogeneous structure of a single organic compound molded product (for example, no optical anisotropy) or a laminated structure of different organic compound molded products as long as it has transparency.

  Examples of such materials include polyamide, polyimide, polypropylene, polyethylpentene, polyvinyl chloride, polyvinyl acetal, polyurethane, polyethyl methacrylate, polycarbonate, polystyrene, polyethylene sulfide, polyether sulfone, polyarylate, polyether ether ketone. , Plastics such as polyethylene terephthalate, polyethylene naphthalate, and triacetyl cellulose. In particular, plastic films such as polyethylene terephthalate, polyethylene naphthalate, polycarbonate, and triacetyl cellulose are preferable from the viewpoint of optical performance, price, and the like.

The thickness of the substrate 2 is appropriately selected from the range of 25 to 300 μm depending on the intended use, and further, depending on the intended use, an ultraviolet absorber, a plasticizer, a lubricant, a colorant, an antioxidant, a difficult Even if a flame retardant or the like is added, there is no particular limitation and no limitation is imposed.
<Hard coat>

In general, the hard coat layer 3 is often used for the purpose of increasing the hardness of the surface of the base material, and the effect thereof is a weather resistance treatment that does not cause scratches such as pencils and scratches caused by steel wool. The material for forming the hard coat layer 3 may be any material having transparency, appropriate hardness, and mechanical strength, and examples thereof include resin materials such as acrylic resin, organic silicon resin, and polysiloxane.
The film thickness of the hard coat layer 3 is preferably in the range of 2 to 30 μm.

In the present invention, the hard coat layer 3 is 4H or more in a pencil hardness test with a load of 500 g as defined in JIS K 5600. Further, in the indentation test, the indentation depth is 50 nm or less and the elastic deformation (load curve and unloading curve is The hard coat layer is required to show a match within 20%).
By forming a hard coat layer having a pencil hardness test of 4H or more and exhibiting elastic deformation, the deformation of the hard coat layer accompanying the deformation of the substrate due to external stress and the deformation of the hard coat layer itself are reduced, and plasticity is achieved. Since no deformation occurs, it is possible to suppress interfacial peeling between the high refractive index transparent thin film layer and the metal thin film layer mainly composed of silver.

Moreover, it is preferable that the Young's modulus calculated | required by the indentation hardness test is 4.5 GPa or more.
If the Young's modulus is 4.5 GPa or more, the deformation of the hard coat layer due to the deformation of the substrate due to external stress and the deformation of the hard coat layer itself are reduced, and plastic deformation does not occur. The interfacial peeling between the transparent thin film layer and the metal thin film layer mainly composed of silver can be suppressed.

In addition, as shown in FIG. 3, the indentation depth in the indentation test of 50 nm or less indicates elastic deformation, as shown in FIG. 3, load curve 1 (point 0 → point A) and unloading curve 2 (point A → point 0). ) Is a close match,
[{(Load curve) − (unload curve)} / (load curve)] × 100 (%)
It is represented by The Young's modulus can be approximated by (applied force F) / (indentation depth d).

  As described above, in order to achieve that the hard coat layer 3 is 4H or higher in the pencil hardness test and that the Young's modulus determined in the indentation hardness test is 4.5 GPa or higher, the hard coat 3 is increased in hardness. However, there is no restriction on the method. When applying the hard coat 3, it is possible to increase the hardness by mixing a resin filler or an inorganic filler in the coating liquid, and they may be used as appropriate.

  In addition, the hard coat layer 3 may be formed into two layers, more layers, or a thick film in order to increase the hardness.

  The hard coat layer 3 may be subjected to a surface treatment for the purpose of improving adhesion between the conductive thin film laminate layer and the transparent thin film layer. As surface treatment methods, corona treatment, high frequency discharge plasma treatment, ion beam treatment, atmospheric pressure glow discharge treatment, vapor deposition, sputtering, dry treatment, and alkali treatment, acid treatment, etc. Processing.

  In the vapor deposition method or the sputtering method, a very thin adhesion layer may be formed, and the materials include metals such as silicon, nickel, chromium, tin, titanium, niobium, tantalum, tungsten, zirconium, palladium, and these metals. An alloy composed of two or more of the following: these oxides, nitrides and the like.

<Conductive thin film layer>
Next, the conductive thin film laminated layer is formed by alternately laminating metal thin film layers and transparent thin film layers, and the base material side and the uppermost layer side are made of transparent thin film layers. The transparent thin film layer is preferably composed of a high refractive index transparent thin film layer having a refractive index of 1.7 or more. By optimizing the physical film thickness and optical film thickness, electromagnetic wave shielding properties, antistatic properties, and antireflection properties can be imparted.
In particular, from the viewpoint of productivity and performance, as shown in FIG. 4, the high refractive index transparent thin film layer 4a, the metal thin film layer 4b, and the high refractive index transparent thin film layer 4a are sequentially formed from the substrate side. preferable.

<High refractive index transparent thin film layer>
The high refractive index transparent thin film layer 4a is selected from those having an optical constant having a refractive index of light in the visible range of 1.7 or more and an extinction coefficient of 0.5 or less.
As such a material, it is desirable to be made of oxide, nitride or oxynitride containing yttrium, titanium, niobium, tantalum, zinc, indium, tin, bismuth, cerium, or a composite thereof.
The high refractive index transparent thin film layer 4a does not necessarily have to be the same material, and can be appropriately selected according to the purpose, such as a vapor deposition method, a sputtering method, an ion plating method, an ion beam assist method, a CVD method, a wet coating method, etc. It can form by the conventionally well-known method. The film thickness of the high refractive index transparent thin film layer 4a is preferably 15 to 70 nm in terms of the shape film thickness.

<Metal thin film layer>
The metal thin film layer 4b preferably has a refractive index of light having a wavelength of 550 nm of 1.0 or less and an extinction coefficient of 10.0 or less.
As such, silver or silver as a main component, gold, copper, magnesium, titanium, zirconium, vanadium, niobium, tantalum, cerium, neodymium, chromium, molybdenum, tungsten, ruthenium, iridium, nickel, palladium, platinum, It is preferable to comprise an alloy or mixture containing at least one selected from zinc, aluminum, indium, silicon, tin, and bismuth.

  The metal thin film layer made of silver is not only easily oxidized by sulfides, halogens, etc., but also is prone to migration when stored under high temperature and high humidity, so silver contains other metal elements to chemically stabilize the silver. It is common to improve the performance. The addition of the metal element is effective for the above-mentioned metals, and two or more kinds may be contained in silver, and the addition amount is not particularly limited, but the optical constant of about 0.1 atomic% to 30 atomic% is silver. It is preferable because it does not change.

  The thickness of the metal thin film layer 4b is preferably 5 to 15 nm in shape and is formed by a conventionally known method such as a vapor deposition method, a sputtering method, an ion plating method, an ion beam assist method, a CVD method, or a wet coating method. it can. Since the metal thin film layer 4b is very thin and requires a highly accurate film thickness distribution, the sputtering method is suitable.

  The conductive thin film laminated layer 4 is not limited to the conductive thin film laminated layer 4 having the three-layer structure in the illustrated example, and the high refractive index metal transparent thin film layer 4a and the metal thin film layer 4b are alternately provided, and the uppermost layer. As long as the lowermost layer is a high refractive index transparent thin film layer 4a, it may be a five-layer alternating laminated structure or a seven-layer alternating laminated structure of a high refractive index transparent thin film layer 4a and a metal thin film layer 4b. By providing the low-refractive-index transparent thin film layer 5 described later, the conductive antireflection laminate 1 has a wide range of visible light wavelength with low reflectivity. From the viewpoint of low cost, a three-layer structure is preferable.

<Low refractive index transparent thin film layer>
Further, a low refractive index transparent thin film layer may be provided on the conductive thin film laminated layer. By providing the low-refractive-index transparent thin film layer on the conductive thin film laminate layer, the reflectance can be made lower than when the conductive thin film laminate layer is formed only by the metal thin film layer and the transparent thin film layer.
The low refractive index transparent thin film layer 5 is selected from those having an optical constant of a visible light refractive index of less than 1.7 and an extinction coefficient of 0.5 or less.
As such, silicon, aluminum, magnesium, barium, calcium, cerium, hafnium, lanthanum, sodium, aluminum, lead, strontium, ytterbium oxide, fluoride, nitride or oxynitride, or a composite thereof It is desirable to be comprised from. Of these, silicon oxide and magnesium fluoride are preferred.
The low refractive index transparent thin film layer 5 can be formed by a conventionally known method such as vapor deposition, sputtering, ion plating, ion beam assist, CVD, or wet coating. The film thickness of the low refractive index transparent thin film layer 5 is preferably 15 to 70 nm in terms of the shape film thickness.

As shown in FIG. 5, the low refractive index transparent thin film layer 5 can have a laminated structure of a high density layer film 5a and a low density layer 5b. Since the internal stress of the low refractive index transparent thin film layer 5 is relieved by the low density layer 5b, delamination hardly occurs. Further, it is possible to suppress the occurrence of defects due to cracks in the low refractive index transparent thin film layer 15 caused by silver migration under high temperature and high humidity. The high-density layer 5a and the low-density layer 5b are not necessarily the same material, and are appropriately selected from the above materials according to the purpose.
The low-refractive-index transparent thin film layer may have a structure in which low-density layers and high-density layers are alternately laminated, or the internal stress of the low-refractive index transparent thin film layer may be reduced by continuously changing the film density. It is valid. Since the high-density layer is finally located on the outermost layer side, the scratch resistance of the low refractive index transparent thin film layer can be enhanced, so that the high scratch resistance of the entire conductive antireflection laminate can be imparted.

  The low refractive index transparent thin film layer 5 is not limited to the two-layer structure of the low density layer 5b and the high density layer 5a. A laminate of the low refractive index transparent thin film layer 5b and the high density layer 5a and a structure in which at least one intermediate density layer (not shown) is sandwiched between the low density layer 5b and the high density layer 5a may be employed. .

  The low refractive index transparent thin film layer 5 is not limited to be formed on the surface in contact with the high refractive index transparent thin film layer 4a on the upper side of the conductive thin film laminated layer 4 shown in FIGS. It may be provided both between the refractive index transparent thin film layer 4 a and the hard coat layer 3.

<Anti-fouling layer>
Further, an antifouling layer may be provided as the uppermost layer.
In FIG. 4, by forming the antifouling layer 6, it is possible to easily wipe off water droplets, fingerprints and the like on the surface of the conductive antireflection laminate 1 and to prevent external damage such as scratches on the surface.
The antifouling layer 6 only needs to have water repellency, oil repellency and low friction, and examples thereof include a layer formed of an organic silane compound, a fluorine-containing silane compound, and a fluorine-containing silicon compound. In particular, it is a layer obtained from a fluorine-containing silicon compound having two or more silicon atoms bonded to a reactive functional group, and the fluorine-containing silicon compound is preferably a layer having an ether bond.

  The antifouling layer 6 can be formed by a wet process such as a micro gravure method, a screen coating method, or a dip coating method in addition to a vacuum dry process such as an evaporation method, a sputtering method, a CVD method, or a plasma polymerization method. It is desirable that the antifouling layer 6 has a shape film thickness of about 5 to 10 nm as long as the antireflection characteristics obtained by the conductive thin film laminated layer 4 and the low refractive index transparent thin film layer 5 are not impaired.

  Moreover, the internal stress of each layer can be decreased and interface peeling can be suppressed because the total film thickness except a base material and a hard-coat layer shall be the shape film thickness of 110 nm or less.

<Adhesion improvement layer>
As shown in FIG. 6, an adhesion improving layer 24c for improving adhesion between layers may be provided between the high refractive index transparent thin film layer 24a and the metal thin film layer 24b. The material of the adhesion improving layer 24c is not particularly limited as long as the effect can be obtained, but at least one metal such as silicon, nickel, chromium, aluminum, magnesium, antimony, titanium, bismuth, tin, niobium, and tantalum is used. Examples include metals and alloys containing more than one kind, oxides and nitrides of the metals. The film thickness of the adhesion improving layer 24c is not particularly limited as long as the transparency of the conductive antireflection laminate 21 is not impaired, but a film thickness of 0.1 to 10 nm is used.

  Hereinafter, the present invention will be described in detail by way of examples. Examples are examples of the present invention, and the content of the present invention is not limited to these examples.

<Example 1>
A conductive antireflection laminate having the structure shown in FIG. 4 was formed.
As a base material 2, on a polyethylene terephthalate film (hereinafter referred to as PET film) having a thickness of 150 μm, an ultraviolet curable resin composition composed of a radical polymerization resin shown below as a first hard coat layer is the same. A coating composition prepared by blending a cationic polymerization resin, which is an ultraviolet curable resin, to a weight composition ratio of 20% and preparing this composition so as to have a resin solid content of 70 wt% with ethyl acetate is used as the first hard coat resin. Used as a liquid.
(Radical polymerization type resin)
Ditrimethylolpropane tetraacrylate 30 parts Pentaerythritol triacrylate 20 parts Radical photopolymerization initiator (Darocur 1173, manufactured by Ciba Geigy)
2 parts (cationic polymerization type resin)
3,4-epoxy-6-methylcyclohexyl methyl carboxylate
45 parts ・ Cyclohexanedimethanol divinyl ether 5 parts ・ Cationic photopolymerization initiator (San-Aid SI-100L, manufactured by Sanshin Chemical Industry Co., Ltd.)
1.5 parts The UV curable coating composition is applied to one side of a PET film by a microgravure method, the solvent is evaporated to form a coating layer having a thickness of about 7 μm, and then the pressure is increased from the coating side. The first hard coat layer 3a was produced by irradiating with ultraviolet rays from a mercury UV lamp (120 W / cm) under the condition of an integrated light quantity of about 250 mJ / m ² and curing.

As the second hard coat layer, an ultraviolet curable coating composition composed only of radical polymerization resin was prepared as a second hard coat resin liquid.
・ Ditrimethylolpropane tetraacrylate 30 parts ・ Pentaerythritol triacrylate 20 parts ・ Darocur 1173 (manufactured by Ciba-Geigy) 2.5 parts ・ Ethyl acetate 30 parts Next, the second composition of the above composition is applied onto the first hard coat layer 3a which has been UV-cured. After forming a coating layer having a thickness of about 8 μm after heat-drying the hard coat layer 3b, ultraviolet rays from a high-pressure mercury UV lamp (120 W / cm) are irradiated from the coating side under a condition of an integrated light quantity of about 300 mJ / m ^2. By performing a curing treatment, a laminate composed of a base material and three layers of the first and second hard coats was obtained.

  The hard coat layer 3 thus obtained was subjected to a pencil hardness test with a load of 500 g as defined in JIS K 5600, which indicated 4H. Furthermore, when Young's modulus was measured with an indentation hardness tester (MTS Nanoindenter XP, using Berkovich indenter), it was 4.9 GPa, and the consistency between the load curve and the unload curve at an indentation depth of 50 nm was about 10%. It showed elastic deformation.

  On the hard coat layer 3, a high refractive index transparent thin film layer 4a, a metal thin film layer 4b, and a high refractive index transparent thin film layer 4a were sequentially laminated to form a conductive thin film laminated layer 4. The high refractive index transparent thin film layer 4a is made of a transparent conductive oxide material (ICO) containing 10 atomic% of cerium in indium. The metal thin film layer 4b is made of 98.5 atomic% of silver, 1.5 atomic% of gold and 0% of copper. Each 5 atomic percent alloy was deposited by sputtering. The first high refractive index transparent thin film layer 4a is 27 nm, the metal thin film layer 4b is 9 nm thick, and the second high refractive index transparent thin film layer 4a is 20 nm thick.

On the high refractive index transparent thin film layer 4a, SiO ₂ was formed with a shape film thickness of 45 nm by a reactive sputtering method to obtain a low refractive index transparent thin film layer 5. Further, a fluorine-based material (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KP801M) was formed on the low-refractive-index transparent thin film layer 5 with a physical film thickness of 6 nm by the vacuum evaporation method to form the antifouling layer 6. The antireflection characteristics of the conductive antireflection laminate 1 thus obtained are shown in FIG.

The scratch resistance test on the antifouling layer side of the conductive antireflection laminate 1 was performed on steel wool (Bonster # 0000) with a load of 250 g / cm ² and a reciprocation count of 50 times. As a result of visual evaluation, no interfacial peeling was confirmed.

<Example 2>
A conductive antireflection laminate having the structure shown in FIG. 5 was formed.
As the base material 2, a first hard coat layer 3 a and a second hard coat layer 3 b are both formed and laminated on a polyethylene terephthalate film (hereinafter referred to as PET film) having a thickness of 150 μm in the same manner as in Example 1. Got the body.

  On the hard coat layer 3, a high refractive index transparent thin film layer 4a, a metal thin film layer 4b, and a high refractive index transparent thin film layer 4a were sequentially laminated to form a conductive thin film laminated layer 4. The high refractive index transparent thin film layer 4a is made of a transparent conductive oxide material (ICO) containing 10 atomic% of cerium in indium. The metal thin film layer 4b is made of 98.5 atomic% of silver, 1.5 atomic% of gold and 0% of copper. Each 5 atomic percent alloy was deposited by sputtering. The first high refractive index transparent thin film layer 4a is 27 nm, the metal thin film layer 4b is 9 nm thick, and the second high refractive index transparent thin film layer 4a is 20 nm thick.

On the high refractive index transparent thin film layer 4a, SiO ₂ is formed as a low density layer 5b having a shape film thickness of 30 nm by reactive sputtering, and SiO ₂ is formed as a high density layer 5a having a shape film thickness of 15 nm by reactive sputtering. The low refractive index transparent thin film layer 5 having a total film thickness of 45 nm was obtained. The method of changing the density of the SiO ₂ layer was performed by changing the film forming pressure. For low density, the film formation pressure was set to a relatively high pressure of 0.7 to 1 Pa, and for high density, the film was formed to a relatively low pressure of 0.1 to 0.3 Pa.

  Further, a fluorine-based material (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KP801M) was formed on the low-refractive-index transparent thin film layer 5 with a physical film thickness of 6 nm by the vacuum evaporation method to form the antifouling layer 6.

A scratch resistance test was conducted on the antifouling layer side of the conductive antireflection laminate 11 obtained in this manner, on steel wool (Bonster # 0000) with a load of 250 g / cm ² and a reciprocation count of 50 times. As a result of visual evaluation, no interfacial peeling was confirmed.

<Example 3>
A conductive antireflection laminate having the structure shown in FIG. 6 was formed.
As the base material 2, both the first hard coat layer 3a and the second hard coat layer 3b were prepared in the same manner as in Example 1 on a polyethylene terephthalate film (hereinafter referred to as PET film) having a thickness of 150 μm. Coat layer 3 was obtained.

On the hard coat layer 3, a high refractive index transparent thin film layer 4a, a metal thin film layer 4b, and a high refractive index transparent thin film layer 4a were sequentially laminated to form a conductive thin film laminated layer 4. The high refractive index transparent thin film layer 4a is made of a transparent conductive oxide material (ICO) containing 10 atomic% of cerium in indium. The metal thin film layer 4b is made of 98.5 atomic% of silver, 1.5 atomic% of gold and 0% of copper. Each 5 atomic percent alloy was deposited by sputtering. The first high refractive index transparent thin film layer 4a is 23 nm, the metal thin film layer 4b is 9 nm thick, and the second high refractive index transparent thin film layer 4a is 16 nm thick. In this embodiment, Nb ₂ O _{5 is used} as the adhesion improving layer 24c after the formation of the high refractive index transparent thin film layer 4a and before the formation of the metal thin film layer 24b and after the formation of the metal thin film layer 4b and before the formation of the high refractive index transparent thin film layer 4a. Nb ₂ O ₅ layers of 4 nm each were formed using a target DC sputtering method.

A low-refractive index having a total film thickness of 45 nm is formed on the high-refractive-index transparent thin film layer 4a by the reactive sputtering method to form the SiO ₂ low-density layer 5b and the high-density layer 5a in the same manner as in Example 2. A transparent thin film layer 5 was obtained.
Further, a fluorine-based material (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KP801M) was formed on the low-refractive-index transparent thin film layer 5 with a physical film thickness of 6 nm by the vacuum evaporation method to form the antifouling layer 6.

A scratch resistance test was performed on the antifouling layer side of the conductive antireflection laminate 1 obtained in this manner, on steel wool (Bonster # 0000) with a load of 250 g / cm ² and a reciprocation count of 50 times. As a result of visual evaluation, no interfacial peeling was confirmed.

<Comparative Example 1>
A hard coat layer 3 was formed on a polyethylene terephthalate film (hereinafter referred to as PET film) having a thickness of 150 μm as the base material 2 in the same manner as in Example 1. However, in this comparative example, an ultraviolet curable coating material was used. The composition is applied to one side of a PET film by a microgravure method, the solvent is evaporated to form a coating layer having a thickness of about 7 μm, and then an ultraviolet ray of a high-pressure mercury UV lamp (120 W / cm) is applied from the coating film side. The first hard coat layer was produced by irradiating with a condition of an integrated light amount of about 200 mJ / m ² and curing, thereby reducing the integrated light amount and reducing the hardness of the hard coat.

In the same manner as in Example 1, the second hard coat layer was prepared by preparing an ultraviolet curable coating composition composed only of radical polymerization type resin as the second hard coat resin liquid and ultraviolet curing the first hard coat layer. A coating layer having a film thickness of about 8 μm after the second hard coat layer having the above composition is thermally dried is formed thereon, and then an ultraviolet ray of a high pressure mercury UV lamp (120 W / cm) is applied from the coating film side to an integrated light amount of about 250 mJ / m. ^By irradiating under the conditions of ² and performing a curing treatment, a laminate composed of a base material and three layers of the first and second hard coats was obtained.
The hard coat layer 3 thus obtained was subjected to a pencil hardness test with a load of 500 g as defined in JIS K 5600, which indicated 2H. Further, when the Young's modulus was measured with an indentation hardness tester in the same manner as described above, it was 3.0 to 3.5 GPa, and the coincidence between the load curve and the unload curve at an indentation depth of 50 nm was about 30%, and plastic deformation was observed. Indicated.

A high refractive index transparent thin film layer 4a, a metal thin film layer 4b, and a high refractive index transparent thin film layer 4a are sequentially laminated on the hard coat layer 3 in the same manner as in Example 1 to form a conductive thin film laminated layer 4, and further a high refractive index. A low refractive index transparent thin film layer 5 was formed by forming SiO ₂ on the transparent thin film layer 4a with a thickness of 45 nm by reactive sputtering. On the low refractive index transparent thin film layer 5, a fluorine-based material (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KP801M) was formed with a physical film thickness of 6 nm by a vacuum deposition method to form an antifouling layer 6.

The scratch resistance test on the antifouling layer side of the conductive antireflection laminate 1 was performed on steel wool (Bonster # 0000) with a load of 250 g / cm ² and a reciprocation count of 50 times. As a result of visual evaluation, scratches can be confirmed, and as a result of performing spectral reflection measurement with a microspectrometer (Olympus lens reflectance measuring instrument USPM-RU), spectral reflectance characteristics of the high refractive index transparent thin film layer 4a on the hard coat layer 3 Met. As a result, it was found that interface peeling occurred between the high refractive index transparent thin film layer 4a and the metal thin film layer 4b.

<Comparative example 2>
A hard coat film was obtained by forming only the first hard coat layer on the polyethylene terephthalate film (hereinafter referred to as PET film) having a thickness of 150 μm as the base material 2 in the same manner as in Comparative Example 1. JIS K 5600 When a pencil hardness test with a load of 500 g as defined in 1 was carried out, it showed 2 H. When the Young's modulus was measured with an indentation hardness tester in the same manner as described above, it was 2.7 to 3.1 GPa and an indentation depth of 50 nm. The coincidence between the loading curve and the unloading curve was about 35%, indicating plastic deformation.

In the same manner as in Example 2, a high refractive index transparent thin film layer 4a, a metal thin film layer 4b, and a high refractive index transparent thin film layer 4a are sequentially laminated on the hard coat layer 3 to form a conductive thin film laminated layer 4, and further a high refractive index. On the transparent thin film layer 4a, SiO ₂ was formed as a low density layer 5b and a high density layer 5a by reactive sputtering to obtain a low refractive index transparent thin film layer 5 having a total film thickness of 45 nm. Next, a fluorine-based material (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KP801M) was formed on the low-refractive-index transparent thin film layer 5 with a physical film thickness of 6 nm by the vacuum evaporation method to form an antifouling layer 6.

A scratch resistance test was performed on the antifouling layer side of the conductive antireflection laminate 1 obtained in this manner, on steel wool (Bonster # 0000) with a load of 250 g / cm ² and a reciprocation count of 50 times. As a result of visual evaluation, a large number of scratches could be confirmed, and as a result of performing spectral reflection measurement with a microspectrometer (Olympus Lens Reflectance Measuring Instrument USPM-RU), a high refractive index transparent thin film layer 4a on the hard coat layer 3 and a metal thin film The spectral reflection characteristics of the layer 4b were mixed. As a result, it was found that interface peeling occurred between the high refractive index transparent thin film layer 4a and the metal thin film layer 4b or between the metal thin film layer 4b and the high refractive index transparent thin film layer 4a.

<Comparative Example 3>
A hard coat layer 3 was formed on a polyethylene terephthalate film (hereinafter referred to as PET film) having a thickness of 150 μm as the transparent substrate 2 in the same manner as in Example 1. However, in this comparative example, an ultraviolet curable type was used. The coating composition was applied to one side of a PET film by a microgravure method, the solvent was evaporated to form a coating layer having a thickness of about 7 μm, and then a high-pressure mercury UV lamp (120 W / cm) was applied from the coating side. A first hard coat layer was produced by irradiating with ultraviolet rays under conditions of an integrated light quantity of about 250 mJ / m ² and curing.

In the same manner as in Example 1, the second hard coat layer was prepared by preparing an ultraviolet curable coating composition composed only of radical polymerization type resin as the second hard coat resin liquid and ultraviolet curing the first hard coat layer. A coating layer having a film thickness of about 8 μm after the second hard coat layer having the above composition is thermally dried is formed thereon, and then an ultraviolet ray of a high-pressure mercury UV lamp (120 W / cm) is applied from the coating film side to an integrated light quantity of about 300 mJ / m. ^By irradiating under the conditions of ² and performing a curing treatment, a laminate composed of a base material and three layers of the first and second hard coats was obtained.
In this comparative example, a second hard coat resin solution was prepared as follows.
・ Ditrimethylolpropane tetraacrylate 30 parts ・ Pentaerythritol triacrylate 20 parts ・ Darocur 1173 (manufactured by Ciba Geigy) 1.5 parts ・ Ethyl acetate 30 parts 500 g as defined in JIS K 5600 for the hard coat layer 3 thus obtained When the pencil hardness test of load was implemented, 4H was shown. Further, when the Young's modulus was measured with an indentation hardness tester in the same manner as described above, it was 3.7 to 4.1 GPa, and the coincidence between the load curve and the unload curve at an indentation depth of 50 nm was about 23%, and plastic deformation was observed. Indicated.

A high refractive index transparent thin film layer 4a, a metal thin film layer 4b, and a high refractive index transparent thin film layer 4a are sequentially laminated on the hard coat layer 3 in the same manner as in Example 1 to form a conductive thin film laminated layer 4, and further a high refractive index. A low refractive index transparent thin film layer 5 was formed by forming SiO ₂ on the transparent thin film layer 4a with a thickness of 45 nm by reactive sputtering. On the low refractive index transparent thin film layer 5, a fluorine-based material (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KP801M) was formed with a physical film thickness of 6 nm by a vacuum deposition method to form an antifouling layer 6.

The scratch resistance test on the antifouling layer side of the conductive antireflection laminate 1 was performed on steel wool (Bonster # 0000) with a load of 250 g / cm ² and a reciprocation count of 50 times. As a result of visual evaluation, scratches can be confirmed, and as a result of performing spectral reflection measurement with a microspectrometer (Olympus lens reflectance measuring instrument USPM-RU), spectral reflectance characteristics of the high refractive index transparent thin film layer 4a on the hard coat layer 3 Met. As a result, it was found that interface peeling occurred between the high refractive index transparent thin film layer 4a and the metal thin film layer 4b.

  According to the present invention from the comparative example of the embodiment, regarding the conductive thin film laminated layer in which the high refractive index transparent thin film layer and the metal thin film layer containing silver as a main component are narrowly supported, or an odd number of layers are laminated. Wide range of conductive anti-reflection laminates with a film thickness of 120 nm or less, which is one configuration of conductive anti-reflection laminates that are excellent in cost and mass productivity in industry, and that provide anti-reflection performance that is practically satisfactory. As a result of intensive studies on one structure that has a high anti-reflection performance and a high transmittance of about 85%, interfacial delamination was observed in a scratch resistance test using steel wool, which is essential for display practicality. It has been found that it is possible to obtain a conductive antireflection laminate having excellent mechanical strength that does not occur.

It is the cross-sectional schematic explaining the problem in the conventional structure. It is a cross-sectional schematic diagram explaining the phenomenon of interface peeling. It is a graph explaining elastic deformation and coincidence. It is sectional drawing which shows an example of the layer structure of the electroconductive antireflection laminated body 1 of this invention. It is sectional drawing which shows another example of the layer structure of the electroconductive antireflection laminated body 10 of this invention. It is sectional drawing which shows another example of the layer structure of the electroconductive antireflection laminated body 20 of this invention. It is a graph which shows an example of the spectral reflection curve of the electroconductive antireflection laminated body 1 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Conductive antireflection laminated body 2 ... Base material 3 ... Hard coat layer 3a ... 1st hard coat layer 3b ... 2nd hard coat layer 4 ... Conductive thin film laminated layer 4a ... High refractive index transparent thin film layer (metal oxide layer)
4b..Metal thin film layer 4c..Adhesion improving layer 5 ... low refractive index layer 5a..low density low refractive index layer 5b..high density low refractive index layer 6 ... antifouling layer a..load Curve 1 (Point 0 → Point A)
b ... Unloading curve 2 (Point A → Point 0)

Claims (11)

  A conductive antireflection laminate having a conductive thin film laminated layer formed by laminating a hard coat layer, a metal thin film layer and a transparent thin film layer on at least a substrate, wherein the hard coat layer is defined in JIS K 5600. It is a hard coat layer that is 4H or more in a pencil hardness test with a load of 500 g, and further shows elastic deformation (the load curve and the unload curve match within 20%) when the indentation depth is 50 nm or less in the indentation test. A conductive antireflection laminate, characterized in that there is.   The conductive antireflection laminate according to claim 1, wherein the Young's modulus determined by an indentation hardness test of the hard coat layer is 4.5 GPa or more.   The conductive antireflection laminate according to claim 1, wherein the conductive thin film laminate is a high refractive index transparent thin film layer / metal thin film layer / high refractive index transparent thin film layer.   The conductive antireflection laminate according to claim 1, wherein the metal thin film layer is silver or an alloy containing silver.   The conductive antireflection laminate according to any one of claims 1 to 4, wherein a low refractive index transparent thin film layer is provided on the conductive thin film laminate layer.   6. The conductive antireflection laminate according to claim 5, wherein the low refractive index transparent thin film layer has a laminated structure of a low density layer and a high density layer, and the high density layer is located on the outermost layer side.   The conductive antireflection laminate according to claim 6, wherein the low refractive index layer transparent thin film has a multilayer structure in which low density layers and high density layers are alternately laminated.   The conductive antireflection laminate according to claim 5, wherein the film density of the low refractive index transparent thin film layer is continuously changed.   The conductive antireflection laminate according to any one of claims 1 to 8, wherein an antifouling layer is provided on the uppermost layer.   The conductive antireflection laminate according to any one of claims 1 to 9, wherein the conductive antireflection laminate has a shape film thickness of 110 nm or less excluding a base material and a hard coat layer.   A display comprising the conductive antireflection laminate according to claim 1 provided on a front surface of the display.

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