JP2014156112A - Light-transmitting conductive film and capacitive type touch panel having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-transmitting conductive film improved in a balance of three properties including an improvement degree in pattern visibility, an improvement degree in interference fringe visibility and a high transmittance.SOLUTION: The light-transmitting conductive film comprises (A) a light-transmitting support layer 11, (B) a hard coat layer 12, (C) an optical interference layer 13, and (D) a light-transmitting conductive layer 14 and satisfies all of the following requirements (1) to (8). They are: (1) 0.01<|n-n|≤0.03, (2) n>n>n, (3) 30<nd-0.0025*(nd)+0.7*(nd)<65, (4) 1.35<n<1.55, (5) 5nm≤d≤50nm, (6) 10nm≤d≤25nm, and (7) 1 μm≤d≤10 μm, relating to the refractive indices and thicknesses of the above layers; and (8) a total ray transmittance is 90% or more.

Description

  The present invention relates to a light-transmitting conductive film and a capacitive touch panel having the same.

  As a conductive film mounted on a touch panel, there are many light transmissive conductive films obtained by laminating a light transmissive conductive layer made of indium tin oxide (ITO) or the like on a light transmissive support layer made of plastic. It is used. The touch panel is used such that the light-transmitting conductive layer side faces the operation surface side. These light-transmitting conductive films are usually provided with a layer having a relatively high surface hardness, called a hard coat layer, for the purpose of preventing scratches on the surface of the light-transmitting support layer. The hard coat layer is usually provided adjacent to the surface on the operation surface side of the light transmissive support layer.

  These light-transmitting conductive films are usually mounted on a touch panel after further patterning the light-transmitting conductive layer by further etching. In the light-transmitting conductive film in which the light-transmitting conductive layer is patterned in this way, the pattern of the light-transmitting conductive layer can be visually recognized on the film surface (so-called bone visibility phenomenon). Are known. The light-transmitting conductive film in which the light-transmitting conductive layer is patterned includes a region where the light-transmitting conductive layer exists (sometimes referred to as “patterned region” in this specification), and a light-transmitting conductive film. Different spectral transmittances and spectral reflectances are shown in a region where there is no layer (in the present specification, sometimes referred to as “non-patterned region”). Such a difference between the spectral transmittance and the spectral reflectance is considered to be a cause of the bone appearance phenomenon.

  Accordingly, various techniques have been proposed for improving the bone appearance phenomenon by paying attention to the difference in refractive index in each of these regions and correcting the difference (Patent Documents 1 to 3). Further, in the patterned light-transmitting conductive layer, a layer having an effect of approximating the reflectance of light incident on the patterned region and the reflectance of light incident on the non-patterned region (such a layer). In this specification, there is also proposed a technique for eliminating the bone-visible phenomenon by providing an “optical interference layer” on the lower layer side of the light-transmitting conductive layer (Patent Document 4). ).

  Further, in the light transmissive conductive film in which the hard coat layer is provided adjacent to the surface on the operation surface side of the light transmissive support layer, another problem is that between the light transmissive support layer and the hard coat layer. The phenomenon that interference fringes are observed on the film surface due to the difference in refractive index is known. This interference fringe phenomenon is known to be mitigated by suppressing the difference in refractive index between the light-transmitting support layer and the hard coat layer within a certain range (Patent Documents 5 and 6).

JP-A-8-240800 JP 2002-98935 A JP 2003-202552 A WO2010 / 114056 gazette JP 7-325201 A JP-A-7-151902

  In order to improve the bone appearance phenomenon, the inventors of the present invention have used a light-transmitting conductive film in which a hard coat layer is provided adjacent to the surface on the operation surface side of the light-transmitting support layer in accordance with a conventional method. If an optical interference layer is provided and the refractive index difference between the light-transmitting support layer and the hard coat layer is suppressed within a certain range for the purpose of improving the interference fringe phenomenon, the following is not known in the past. We have discovered that this problem will occur through our original study. The problem is that the refractive index of each layer constituting the light-transmitting conductive film is inevitably high, and as a result, the film has a high transmittance, for example, a transmittance of 90% or more. It is a problem that is difficult. In general, the higher the transmittance of the film, the more easily the phenomenon of bone appearance tends to be promoted. That is, it is difficult to improve the transmittance of the film and the improvement of the bone appearance phenomenon.

  The present invention provides a light-transmitting conductive film having an improved three-way balance consisting of (1) a degree of improvement of the bone appearance phenomenon, (2) a degree of improvement of the interference fringe phenomenon, and (3) a high transmittance. It is an issue to provide.

The inventors of the present invention have intensively studied to solve the above problems and have completed the present invention. The present invention solves the above-mentioned problems, and is as follows.
Item 1.
(A) a light transmissive support layer;
(B) hard coat layer;
(C) an optical interference layer; and (D) a light transmissive conductive film containing a light transmissive conductive layer,
The hard coat layer (B) is directly disposed on at least one surface of the light transmissive support layer (A),
The light transmissive conductive layer (D) is disposed on at least one of the hard coat layers (B) on the surface opposite to the light transmissive support layer (A) via at least the optical interference layer (C). And a light-transmissive conductive film characterized by satisfying all of the following requirements (1) to (8).
(1) 0.01 <| n _A −n _B | ≦ 0.03
(2) n _D > n _A > n _C
(3) 30 <n _C d _C −0.0025 * (n _D d _D ) ² + 0.7 * (n _D d _D ) <65
(4) 1.35 <n _C <1.55
(5) 5 nm ≦ d _C ≦ 50 nm
(6) 10 nm ≦ d _D ≦ 25 nm
(7) 1 μm ≦ d _B ≦ 10 μm
(8) The total light transmittance is 90% or more (in the above,
n _A represents the refractive index of the light transmissive support layer (A);
n _B represents the refractive index of the hard coat layer (B);
n _C represents the refractive index of the optical interference layer (C);
n _D represents the refractive index of the light-transmissive conductive layer (D);
d _B represents the thickness (μm) of the hard coat layer (B);
d _C is the thickness (nm) of the optical interference layer (C);
d _D is the thickness (nm) of the light transmissive conductive layer (D);
Each is shown. )
Item 2.
Item 2. The light transmissive conductive film according to Item 1, wherein at least one of the light transmissive conductive layers (D) contains indium tin oxide.
Item 3.
Item 3. The light transmissive conductive film according to Item 1 or 2, wherein at least one of the optical interference layers (C) contains SiO _x (x = 1 to 2).
Item 4.
Item 4. A capacitive touch panel comprising the light transmissive conductive film according to any one of Items 1 to 3.

  In the light transmissive conductive film, the balance of the three can be improved, which consists of (1) the improvement degree of the bone appearance phenomenon, (2) the improvement degree of the interference fringe phenomenon, and (3) the high transmittance. More details are as follows. First, when the light-transmitting conductive layer is patterned, the reflectance of light incident on the region where the light-transmitting conductive layer is present and the reflectance of light incident on the region where the light-transmitting conductive layer is not present By using an optical interference layer having an effect of approximating each other, the bone appearance phenomenon can be improved. Second, the interference fringe phenomenon can be improved by suppressing the difference in refractive index between the light-transmitting support layer and the hard coat layer within a certain range. Third, by adjusting the refractive index and thickness of the optical interference layer and the thickness of the light-transmitting conductive layer within a predetermined range, and adjusting the refractive index and thickness of each layer to satisfy a predetermined relationship. High transmittance can be imparted to the film while maintaining the above effects.

The light of the present invention, wherein a hard coat layer (B), an optical interference layer (C), and a light transmissive conductive layer (D) are arranged adjacent to each other in this order on one side of the light transmissive support layer (A). It is sectional drawing which shows a permeable conductive film. In the present invention, the hard coat layer (B), the optical interference layer (C), and the light transmissive conductive layer (D) are disposed adjacent to each other in this order on both surfaces of the light transmissive support layer (A). It is sectional drawing which shows this light transmissive conductive film. A hard coat layer (B), an optical interference layer (C), and a light transmissive conductive layer (D) are arranged adjacent to each other in this order on one side of the light transmissive support layer (A), and light transmissive It is sectional drawing which shows the light-transmitting conductive film of this invention by which another hard-coat layer (B) is arrange | positioned adjacent to the other surface of a transparent support layer (A). It is drawing which shows the result of an Example and a comparative example.

1. Light transmissive conductive film The light transmissive conductive film of the present invention comprises:
(A) a light transmissive support layer;
(B) hard coat layer;
(C) an optical interference layer; and (D) a light transmissive conductive film containing a light transmissive conductive layer,
The hard coat layer (B) is directly disposed on at least one surface of the light transmissive support layer (A),
The light transmissive conductive layer (D) is disposed on at least one of the hard coat layers (B) on the surface opposite to the light transmissive support layer (A) via at least the optical interference layer (C). The light-transmitting conductive film is characterized in that it satisfies all of the following requirements (1) to (8).
(1) 0.01 <| n _A −n _B | ≦ 0.03
(2) n _D > n _A > n _C
(3) 30 <n _C d _C −0.0025 * (n _D d _D ) ² + 0.7 * (n _D d _D ) <65
(4) 1.35 <n _C <1.55
(5) 5 nm ≦ d _C ≦ 50 nm
(6) 10 nm ≦ d _D ≦ 25 nm
(7) 1 μm ≦ d _B ≦ 10 μm
(8) The total light transmittance is 90% or more (in the above,
n _A represents the refractive index of the light transmissive support layer (A);
n _B represents the refractive index of the hard coat layer (B);
n _C represents the refractive index of the optical interference layer (C);
n _D represents the refractive index of the light-transmissive conductive layer (D);
d _B represents the thickness (μm) of the hard coat layer (B);
d _C is the thickness (nm) of the optical interference layer (C);
d _D is the thickness (nm) of the light transmissive conductive layer (D);
Each is shown. )

  In this specification, when mentioning the relative positional relationship between two layers among a plurality of layers arranged on one surface of the light transmissive support layer (A), the light transmissive support layer (A) is used as a reference. Thus, one layer having a large distance from the light transmissive support layer (A) may be referred to as an “upper” layer or the like.

  In FIG. 1, the one aspect | mode of the transparent electroconductive film of this invention is shown. In this embodiment, the hard coat layer (B), the optical interference layer (C), and the light transmissive conductive layer (D) are arranged adjacent to each other in this order on one surface of the light transmissive support layer (A).

  In the present invention, the thickness of each layer is determined using a commercially available reflection spectral film thickness meter (Otsuka Electronics, FE-3000 (product name), or equivalent). Alternatively, it may be obtained by observation using a commercially available transmission electron microscope. Specifically, the light-transmitting conductive film is thinly cut in a direction perpendicular to the film surface using a microtome or a focus ion beam, and the cross section is observed.

  The light transmissive conductive film of the present invention has a total light transmittance of 90% or more. In the present invention, the total light transmittance is measured based on JIS-K-7105 using a haze meter (trade name: NDH-2000 manufactured by Nippon Denshoku Co., Ltd. or equivalent).

1.1 Light transmissive support layer (A)
In the present invention, the light-transmitting support layer refers to a light-transmitting conductive film containing a light-transmitting conductive layer that plays a role of supporting a layer including the light-transmitting conductive layer. Although it does not specifically limit as a light transmissive support layer (A), For example, in the light transmissive conductive film for touch panels, what is normally used as a light transmissive support layer can be used.

Although the raw material of a light-transmissive support layer (A) is not specifically limited, For example, various organic polymers etc. can be mentioned. The organic polymer is not particularly limited. For example, polyester resin, acetate resin, polyether resin, polycarbonate resin, polyacrylic resin, polymethacrylic resin, polystyrene resin, polyolefin resin, polyimide resin, etc. Examples thereof include resins, polyamide resins, polyvinyl chloride resins, polyacetal resins, polyvinylidene chloride resins, and polyphenylene sulfide resins. Although it does not specifically limit as polyester-type resin, For example, a polyethylene terephthalate (PET), a polyethylene naphthalate (PEN), etc. are mentioned. The material of the light transmissive support layer (A) is preferably a polyester resin, and particularly preferably PET. The light transmissive support layer (A) may be composed of any one of them, or may be composed of a plurality of types.

  Although the thickness of a light-transmissive support layer (A) is not specifically limited, For example, the range of 2-300 micrometers is mentioned.

1.2 Hard coat layer (B)
The hard coat layer (B) is directly disposed on at least one surface of the light transmissive support layer (A). In other words, the hard coat layer (B) is disposed adjacent to at least one surface of the light transmissive support layer (A).

  One layer of the hard coat layer (B) may be disposed. Alternatively, two or more layers may be arranged adjacent to each other or separated from each other via other layers.

  The hard coat layer (B) may be disposed on both surfaces of the light transmissive support layer (A).

  In this invention, a hard-coat layer means what plays the role which prevents the damage | wound of the surface of a light-transmissive support layer (A). Although it does not specifically limit as a hard-coat layer (B), For example, what is normally used as a hard-coat layer in the transparent conductive film for touchscreens can be used.

  The material for the hard coat layer (B) is not particularly limited, and examples thereof include acrylic resins, silicone resins, urethane resins, melamine resins, and alkyd resins. Examples of the material for the hard coat layer (B) further include those obtained by dispersing colloidal particles such as silica, zirconia, titania and alumina in the resin. The hard coat layer (B) may be composed of any one of these, or may be composed of a plurality of types. As the hard coat layer (B), an acrylic resin in which zirconia particles are dispersed is preferable.

The thickness of the hard coat layer (B) (the total thickness of the two layers when two layers are arranged adjacent to each other) d _B (μm) is 1 μm to 10 μm. When d _B (μm) is 1 μm or more, preferable hardness is imparted to the film. Further, when d _B (μm) is 10 μm or less, the film is hardly curled.

d _B (μm) is preferably 1 μm to 5 μm, and more preferably 1 μm to 2.5 μm.

  The method of disposing the hard coat layer (B) is not particularly limited, and examples thereof include a method of applying to a film and curing with heat, a method of curing with active energy rays such as ultraviolet rays and electron beams, and the like. From the viewpoint of productivity, a method of curing with ultraviolet rays is preferable.

1.3 Optical interference layer (C)
The optical interference layer (C) is a layer having an effect of approximating the reflectance of light incident on the patterned region and the reflectance of light incident on the non-patterned region.

  More specifically, the optical interference layer (C) has a refractive index having a predetermined relationship described later with the refractive indexes of the light-transmitting conductive layer (D) and the light-transmitting support layer (A). In addition, by having a predetermined thickness to be described later, an optical interference condition that achieves a small color difference between the patterned region and the non-patterned region is achieved.

The optical interference layer (C) is disposed on at least one surface of the light transmissive support layer (A) via at least the hard coat layer (B). In other words, the optical interference layer (C) is disposed on the surface of at least one hard coat layer (B) opposite to the light transmissive support layer (A), directly or via one or more other layers. ing.

  One layer of the optical interference layer (C) may be disposed. Alternatively, two or more layers may be arranged adjacent to each other or separated from each other via other layers.

  The refractive index of the optical interference layer (C) has a predetermined relationship with the refractive indexes of the light transmissive conductive layer (D) and the light transmissive support layer (A). This relationship will be described later. In addition to this, the refractive index of the optical interference layer (C) needs to be within a predetermined range. This range will also be described later.

  The thickness of the optical interference layer (C) (when two layers are arranged adjacent to each other) needs to be equal to or less than a predetermined numerical value. This range will be described later. The thickness of the optical interference layer (C) is 5 nm or more. This improves the adhesion with the light-transmitting conductive layer (D) disposed thereon. From the viewpoint of adhesion, the thickness of the optical interference layer (C) is preferably 5 nm or more, more preferably 7 nm or more, and further preferably 10 nm or more.

The material of the optical interference layer (C) is not particularly limited, but may be, for example, a dielectric material. The material of the optical interference layer (C) is not particularly limited. For example, silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon alkoxide, alkylsiloxane and its condensate, polysiloxane, silsesquioxane, polysilazane. And acrylic silica hybrid. The optical interference layer (C) may be composed of any one of them, or may be composed of a plurality of types. As the optical interference layer (C), an optical interference layer containing one selected from the group consisting of polysilazane, acrylic silica hybrid and SiO _x (x = 1 to 2) is preferable. The optical interference layer (C) may be an optical interference layer made of one selected from the group consisting of polysilazane, acrylic silica hybrid, and SiO _x (x = 1 to 2). As the optical interference layer (C), an optical interference layer containing SiO _x (x = 1 to 2) is preferable. The optical interference layer (C) may be an optical interference layer made of SiO _x (x = 1 to 2). Hereinafter, for example, an optical interference layer made of SiO _x (x = 1 to 2) may be abbreviated as an SiO _x layer.

Examples of embodiments in which two or more optical interference layers (C) are arranged adjacent to each other include, for example, stacking composed of adjacent SiO ₂ layers and SiO _x layers, and adjacent SiO ₂ layers and SiO ₂ laminate consisting _x N _y layer. For example, when two layers are arranged adjacent to each other, the order of the SiO ₂ layer and the SiO _x layer is arbitrary, but the optical interference layer (C-1) made of SiO ₂ on the light transmissive support layer (A) side. ), An optical interference layer (C-2) made of SiO _x (x = 1 to 2) is preferably disposed on the light transmissive conductive layer (D) side.

  Examples of the method for disposing the optical interference layer (C) include a method of laminating on an adjacent layer by a sputtering method, an ion plating method, a vacuum deposition method, and a pulse laser deposition method.

1.4 Light transmissive conductive layer (D)
The light transmissive conductive layer (D) is disposed on at least one of the hard coat layers (B) on the surface opposite to the light transmissive support layer (A) via at least the optical interference layer (C). .

In the present invention, the light-transmitting conductive layer means a layer that conducts electricity and transmits visible light. Although it does not specifically limit as a light transmissive conductive layer (D), For example, what is normally used as a light transmissive conductive layer in the light transmissive conductive film for touch panels can be used.

  The material for the light transmissive conductive layer (D) is not particularly limited, and examples thereof include indium oxide, zinc oxide, tin oxide, and titanium oxide. The light transmissive conductive layer (D) is preferably a light transmissive conductive layer containing indium oxide doped with a dopant from the viewpoint of achieving both transparency and conductivity. The light transmissive conductive layer (D) may be a light transmissive conductive layer made of indium oxide doped with a dopant. Although it does not specifically limit as a dopant, For example, a tin oxide, a zinc oxide, those mixtures, etc. are mentioned.

In the case of using indium oxide doped with tin oxide as the material of the light transmissive conductive layer (D), indium oxide (III) (In ₂ O ₃ ) doped with tin (IV) oxide (SnO ₂ ) (Tin-doped indium oxide; ITO) is preferable. In this case, the addition amount of SnO ₂ is not particularly limited, and examples thereof include 1 to 15% by weight, preferably 2 to 10% by weight, and more preferably 3 to 8% by weight. Moreover, you may use as a raw material of a transparent conductive layer (D) what added the other dopant to indium tin oxide in the range which the total amount of a dopant does not exceed the numerical range of the left description. Although it does not specifically limit as another dopant in the left, For example, selenium etc. are mentioned.

  The light transmissive conductive layer (D) may be composed of any one of the above-mentioned various materials, or may be composed of a plurality of types.

  The light transmissive conductive layer (D) is not particularly limited, but may be a crystalline or amorphous body, or a mixture thereof.

  The thickness of the light transmissive conductive layer (D) needs to be a predetermined numerical value or less. This range will be described later. The light transmissive conductive layer (D) has a thickness of 10 nm or more.

  The method of disposing the light transmissive conductive layer (D) may be either wet or dry, and is not particularly limited. Specific examples of the method for disposing the light transmissive conductive layer (D) include, for example, a sputtering method, a vacuum deposition method, an ion plating method, a CVD method, and a pulse laser deposition method.

1.5 requirements (1) to (6)
The light-transmitting conductive film of the present invention further satisfies all the following requirements (1) to (4), (5 ′), and (6 ′) in addition to all the characteristics described so far.

(1) 0.01 <| n _A −n _B | ≦ 0.03
(2) n _D > n _A > n _C
(3) 30 <n _C d _C −0.0025 * (n _D d _D ) ² + 0.7 * (n _D d _D ) <65
(4) 1.35 <n _C <1.55
(5 ′) d _C ≦ 50 nm
(6 ′) d _D ≦ 25 nm
(In the above,
n _A represents the refractive index of the light transmissive support layer (A);
n _B represents the refractive index of the hard coat layer (B);
n _C represents the refractive index of the optical interference layer (C);
n _D represents the refractive index of the light-transmissive conductive layer (D);
d _C is the thickness (nm) of the optical interference layer (C);
d _D is the thickness (nm) of the light transmissive conductive layer (D);
Each is shown. )
In addition to all the characteristics described so far, the light-transmitting conductive film of the present invention further satisfies all the above requirements (1) to (4) and (5 ′) and (6 ′), The balance between the three, which is composed of the improvement degree of the bone appearance phenomenon, the improvement degree of the interference fringe phenomenon, and the high transmittance, is improved. More details are as follows.

  First, by satisfying the above requirement (1), the refractive index difference between the light-transmitting support layer (A) and the hard coat layer (B) is kept within a certain range, and so Can be prevented from being observed on the film surface.

  Secondly, in addition to all the characteristics described so far, the requirements (2) to (4) and (5 ′) and (6 ′) are satisfied, so that the optical interference layer (C) It is excellent in the effect of approximating the reflectance of light incident on the patterned region and the reflectance of light incident on the non-patterned region. Thereby, the bone appearance phenomenon is improved. Further, at the same time, the light-transmitting conductive film of the present invention improves the bone appearance phenomenon and the interference fringe phenomenon by satisfying the above requirements (2) to (4) and (5 ′) and (6 ′). As a whole, the transmittance is high.

The requirement (3) includes the reflection spectrum of light incident on the patterned region and the non-patterning within the constraints of the requirements (1), (2), (4), and (5 ′) (6 ′). The point at which the color difference ΔE ^* ab of the reflection spectrum of light incident on the region is minimized by optical simulation is used as a center value, and the condition under which the color difference ΔE ^* ab is within 2 is expressed by an approximate curve.

As described in requirement (4) above, n _C needs to be 1.35 to 1.55. When n _C is 1.35 or more, the more preferable optical interference condition is obtained, and the effect of improving the bone appearance phenomenon is improved. Also, by _{n C} is 1.55 or less, the transmittance of the film is improved.

1.6 Other layers The light-transmitting conductive film of the present invention has a hard coat layer (B), an optical interference layer (C), and a light-transmitting conductive film on at least one surface of the light-transmitting support layer (A). In addition to the layer (D), at least one other layer (E) different from them may be further arranged.

  Although it does not specifically limit as another layer different from any of (A)-(D), For example, an adhesive layer etc. are mentioned.

  The adhesive layer is a layer that is disposed between two layers so as to be adjacent to each other and to adhere the two layers to each other. Although it does not specifically limit as a contact bonding layer, For example, what is normally used as a contact bonding layer in the transparent conductive film for touchscreens can be used. The adhesive layer may be composed of any one of these, or may be composed of a plurality of types.

1.7 Use of light-transmitting conductive film of the present invention The light-transmitting conductive film of the present invention is used for manufacturing a touch panel. Although it does not specifically limit, It is preferably used for manufacture of a capacitive touch panel. The details of the capacitive touch panel are as described in 2.

2. Capacitive touch panel of the electrostatic capacitance type touch panel <br/> invention of the present invention comprises a light transmissive, electrically-conductive film of the present invention, comprise other members according to necessity.

Specific examples of the configuration of the capacitive touch panel according to the present invention include the following configurations. It should be noted that the protective layer (1) side is used with the operation screen side and the glass (5) side faces the opposite side of the operation screen.
(1) Protective layer (2) Light transmissive conductive film of the present invention (Y-axis direction)
(3) Insulating layer (4) Light transmissive conductive film of the present invention (X-axis direction)
(5) Glass Although the capacitive touch panel of the present invention is not particularly limited, for example, it can be produced by combining the above (1) to (5) and other members as required according to a usual method. it can.

3. Manufacturing method of light-transmitting conductive film of the present invention The manufacturing method of the light-transmitting conductive film of the present invention includes a hard coat layer (B), optical interference on at least one surface of the light-transmitting support layer (A). Each includes a step of disposing the layer (C) and the light-transmitting conductive layer (D), and if necessary, at least one other layer (E) different from them.

  The step of arranging each layer is as described for each layer. In the case where at least one other layer is disposed in addition to the light transmissive conductive layer (D), for example, the light transmissive support layer (A) side is provided on at least one surface of the light transmissive support layer (A). However, the order of arrangement is not particularly limited. For example, you may arrange | position another layer to one side of the layer (for example, light transmissive conductive layer (D)) which is not a light transmissive support layer (A) first. Alternatively, one composite layer is obtained by arranging two or more layers adjacent to each other on the one hand, or at the same time, two or more layers are similarly disposed adjacent to each other on the other side. Thus, one type of composite layer may be obtained, and these two types of composite layers may be further arranged adjacent to each other.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.
1. Various measurement methods Various measurements in the examples were performed as follows.

1.1 Thickness and refractive index The thickness and refractive index of the transparent conductive layer, optical interference layer, and hard coat are simply applied to a suitable thermoplastic film substrate having a refractive index different from those of the layers under the same coating conditions. The layers were laminated and calculated by optical simulation using the wavelength of the maximum peak or minimum peak of the reflectance expressed on the light reflection spectrum of the layered surface and the value of the peak reflectance. In the present invention, the refractive index is the refractive index for light having a wavelength of 550 nm unless otherwise specified.

1.2 Reflection spectrum The reflection spectrum was measured with a spectrophotometer UV-3101PC manufactured by Shimadzu Corporation. Note that the incident angle of the measurement light to the sample is 5 degrees, and a light-shielding layer is formed on the back side using a commercially available black spray, and measurement is performed with almost no light reflected from the back side or the back side of the sample. went. The reflectance spectrum of the patterned region was obtained by measuring the reflectance spectrum of the laminate after forming the transparent conductive layer. Moreover, the reflectance spectrum of the non-patterned area | region was obtained by measuring the reflectance spectrum of the laminated body after removing the produced transparent conductive laminated body with an etching liquid.

1.3 Transmittance The total light transmittance measured according to JIS K7361-1 using a Nippon Denshoku haze meter (MDH2000) was used.

1.4 Bone Visibility The produced transparent conductive laminate was cut into a 5 cm square, and 8 pieces of 3 mm wide polyimide tape were attached to the transparent conductive layer in parallel so as to form a 3 mm gap. Next, the laminate with the polyimide tape attached is immersed in an ITO etching solution (trade name “ITO-06N”, manufactured by Kanto Chemical Co., Ltd.) for 1 minute to remove the ITO where the polyimide tape is not attached, and rinse. And the polyimide tape was peeled after drying, and the laminated body by which the ITO film | membrane of 3 mm width was patterned by the 3 mm space | interval was obtained. This film was visually observed to evaluate whether the ITO pattern corresponds to one of “almost invisible (◯)”, “somewhat visible (Δ)”, and “visible (×)”.

2. Examples and Comparative Examples 2.1 Example 1
The light transmissive conductive film of the present invention was obtained as follows.

On the surface of the easy adhesion treatment side of a 125 μm thick PET resin substrate (n _A = 1.659),
A photoreactive coating solution prepared as described below was applied, and heat-dried and then irradiated with ultraviolet rays to form a 1.68 μm thick hard coat layer (n _B = 1.631).

  The photoreactive coating solution was prepared in detail as follows.

Dipentaerythritol hexaacrylate (Nippon Kayaku Co., Ltd.) 75 parts by weight Epoxy acrylate (Nippon Kayaku Co., Ltd.) 20 parts by weight Macromonomer AA-6 (Toagosei Co., Ltd.) 11 parts by weight Zirconium oxide-based highly refractive fine particles HZ- 307
(Nissan Chemical Co., Ltd .: solid content 30%) 100 parts by weight Photopolymerization initiator Irgacure 184 (manufactured by Ciba Geigy) 7 parts by weight A mixed solvent containing 35 parts by weight of butyl cellosolve and 94.5 parts by weight of methyl ethyl ketone. The resulting solution was diluted and stirred well to obtain a photoreactive coating solution having a solid content of 40%.

Next, a layer (n _C = 1.460) made of SiO _{2 having a} thickness of 20 nm is formed on the hard coat layer as an optical interference layer, and further a layer made of indium tin oxide (n _D = 1.938) was deposited to a thickness of 18 nm. Specifically, a SiO ₂ layer is formed by a DC magnetron sputtering method using a sintered body material consisting of 97% by weight of indium oxide and 3% by weight of tin oxide as a target material, and indium oxide is formed thereon. A tin layer was formed.

2.2 Example 2
A light-transmitting conductive film of the present invention was obtained in the same manner as in Example 1 except that a 13-nm thick SiO ₂ layer was formed as an optical interference layer and a 23-nm thick indium tin oxide layer was formed.

2.3 Example 3
As an optical interference layer, a low refractive index layer (n _C = 1.371) containing hollow fine particles was formed as follows and an indium tin oxide layer was formed to a thickness of 23 nm. In the same manner as in Example 1, a light transmissive conductive film of the present invention was obtained.

  Specifically, the low refractive index optical interference layer containing hollow fine particles was formed as follows.

A dispersion of hollow silica-based fine particles (P-2) prepared as follows was applied with an extrusion coater, dried at 100 ° C. for 1 minute, then cured by irradiation with ultraviolet rays of 0.1 J / cm ² , and A low refractive index layer was provided so as to have a thickness of 25 nm by thermosetting at 120 ° C. for 5 minutes.

Tetraethoxysilane hydrolyzate A 110 parts by mass Hollow silica-based fine particles (P-2 below) 30 parts by mass KBM503 (silane coupling agent, manufactured by Shin-Etsu Chemical Co., Ltd.) 4 parts by mass Linear dimethyl silicone-EO block copolymer (FZ) -2207, manufactured by Nippon Unicar Co., Ltd.) 10% propylene glycol monomethyl ether solution 3 parts by mass Propylene glycol monomethyl ether 400 parts by mass Isopropyl alcohol 400 parts by mass In addition, tetraethoxysilane hydrolyzate A was prepared as follows. .

  Hydrolyzate A was prepared by mixing 289 g of tetraethoxysilane and 553 g of ethanol, adding 157 g of 0.15% aqueous acetic acid solution thereto, and stirring in a water bath at 25 ° C. for 30 hours.

  Moreover, the hollow silica type fine particles P-2 were prepared as follows.

A mixture of 100 g of silica sol having an average particle diameter of 5 nm and a SiO ₂ concentration of 20% by mass and 1900 g of pure water was heated to 80 ° C. The pH of this reaction mother liquor was 10.5, and 9000 g of 0.98 mass% sodium silicate aqueous solution as SiO ₂ and 9000 g of 1.02 mass% sodium aluminate aqueous solution as Al ₂ O ₃ were simultaneously added to the mother liquor. did. Meanwhile, the temperature of the reaction solution was kept at 80 ° C. The pH of the reaction solution rose to 12.5 immediately after the addition and hardly changed thereafter. After completion of the addition, the reaction solution was cooled to room temperature and washed with an ultrafiltration membrane to prepare a SiO ₂ .Al ₂ O ₃ core particle dispersion having a solid content concentration of 20% by mass.

1700 g of pure water is added to 500 g of this core particle dispersion and heated to 98 ° C., and while maintaining this temperature, a silicic acid solution (SiO ₂₎ obtained by dealkalizing a sodium silicate aqueous solution with a cation exchange resin. A dispersion of core particles in which 3000 g (concentration of 3.5% by mass) was added to form a first silica coating layer was obtained.

Next, 1125 g of pure water is added to 500 g of the core particle dispersion liquid that has been washed with an ultrafiltration membrane to form a first silica coating layer having a solid content concentration of 13% by mass, and concentrated hydrochloric acid (35.5%) is further added dropwise. The pH was adjusted to 1.0 and dealumination was performed. Next, the aluminum salt dissolved in the ultrafiltration membrane was separated while adding 10 L of hydrochloric acid aqueous solution of pH 3 and 5 L of pure water, and SiO ₂ · Al from which some of the constituent components of the core particles forming the first silica coating layer were removed. A dispersion of ₂ O ₃ porous particles was prepared.

A mixture of 1500 g of the above porous particle dispersion, 500 g of pure water, 1,750 g of ethanol, and 626 g of 28% ammonia water was heated to 35 ° C., and then ethyl silicate (SiO ₂
(28% by mass) 104 g was added, and the surface of the porous particles on which the first silica coating layer was formed was coated with a hydrolyzed polycondensate of ethyl silicate to form a second silica coating layer. Subsequently, a dispersion of hollow silica-based fine particles (P-2) having a solid content concentration of 20% by mass in which the solvent was replaced with ethanol using an ultrafiltration membrane was prepared.

The thickness of the first silica coating layer of the hollow silica-based fine particles was 3 nm, the average particle size was 47 nm, the MO _x / SiO ₂ (molar ratio) was 0.0017, and the refractive index was 1.28. Here, the average particle diameter was measured by a dynamic light scattering method.

2.4 Example 4
As an optical interference layer, a layer made of a silicon-based resin having a thickness of 20 nm as follows (n _C = 1.50)
2) and the light-transmitting conductive film of the present invention was obtained in the same manner as in Example 1 except that the thickness of the indium tin oxide layer was 18 nm.

  The silicon resin layer was obtained by applying a silicon resin coating solution prepared as follows and performing a heat treatment at 130 ° C. for 5 minutes.

  In a mixed solvent of 2-propanol 1080 parts by weight / acetic acid 46 parts by weight / water 720 parts by weight, 3-glycidoxypropyltrimethoxysilane 480 parts by weight, methyltrimethoxysilane 240 parts by weight and N-2- (aminoethyl) 120 parts by weight of 3-aminopropyltrimethoxysilane was added to prepare an alkoxysilane mixed solution, and this alkoxysilane mixed solution was stirred for 3 hours to partially condense, and then the weight of isopropyl alcohol and 1-methoxy-2-propanol. It diluted with the mixed solvent of ratio 1: 1, and obtained the silicon-type resin coating liquid.

2.5 Comparative Example 1
A light transmissive conductive film was obtained as follows.

_A photoreactive coating solution prepared as follows is applied on the surface of the 100 μm-thick polycarbonate resin substrate (n _A = 1.585) on the easy adhesion treatment side. Irradiation formed a 3 μm thick hard coat layer (n _B = 1.590).

Bisphenoxyethanol full orange acrylate (manufactured by Osaka Gas Co., Ltd.) 59 parts by weight Urethane acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., NK Oligo U-15HA) 41 parts by weight Irgacure 184 (manufactured by Ciba Geigy) 3 parts by weight The above components are mixed with 1-methoxy-2-propanol A photoreactive coating solution was obtained by diluting with stirring and mixing.

Next, the optical interference coating solution 1 prepared as described below was applied onto the hard coat layer, and heat treatment was performed at 130 ° C. for 5 minutes to form a 100 nm thick TiO ₂ -containing silicon-based resin layer (n _C =
1.695) was formed on the hard coat layer.

  In a mixed solvent of 2-propanol 1080 parts by weight / acetic acid 46 parts by weight / water 720 parts by weight, 3-glycidoxypropyltrimethoxysilane 480 parts by weight, methyltrimethoxysilane 240 parts by weight and N-2- (aminoethyl) 120 parts by weight of 3-aminopropyltrimethoxysilane was added to prepare an alkoxysilane mixed solution, and this alkoxysilane mixed solution was stirred for 3 hours to partially condense, and then the weight of isopropyl alcohol and 1-methoxy-2-propanol. It diluted with the mixed solvent of ratio 1: 1. In this liquid, titanium oxide ultrafine particles 15 wt% isopropyl alcohol dispersion (CI Chemical Co., Ltd., average primary particle diameter of ultrafine particles 30 nm) 3024 parts by weight (solid content conversion 453 parts by weight, cured resin 100 parts by weight after curing On the other hand, 78 parts by weight of ultrafine particles) was added and stirred and mixed for 10 minutes to obtain a coating solution 1 for optical interference.

Further, a layer (n _D = 2.100) made of indium tin oxide having a thickness of 20 nm was formed. Specifically, an indium tin oxide layer was formed by a DC magnetron sputtering method using a sintered body material composed of 95% by weight of indium oxide and 5% by weight of tin oxide as a target material. Subsequently, heat treatment was performed at 130 ° C. for 90 minutes to crystallize the indium tin oxide layer.

2.6 Comparative Example 2
On the surface of the easy-adhesion treatment side of a PET resin substrate (n _A = 1.695) having a thickness of 188 μm,
A photoreactive coating solution was applied in the same manner as in Comparative Example 1 except that the coating thickness was changed, and a hard coat layer (n _B = 1.590) having a thickness of 3.5 μm was irradiated with ultraviolet rays after heat drying. Formed.

Next, a coating solution 2 for light interference prepared as described below was applied on the hard coat layer, heated and dried, and then irradiated with ultraviolet rays to form an acrylic resin layer having a thickness of 3.5 μm, and then the coating thickness The optical interference coating liquid 1 was applied in the same manner as in Comparative Example 1 except that the heat treatment was performed at 130 ° C. for 5 minutes, and a 90 nm thick TiO ₂ -containing silicon-based resin layer (n _C = 1. 700) was formed on the acrylic resin layer.

  In a mixed solvent of 2-propanol 1080 parts by weight / acetic acid 46 parts by weight / water 720 parts by weight, 3-glycidoxypropyltrimethoxysilane 480 parts by weight, methyltrimethoxysilane 240 parts by weight and N-2- (aminoethyl) 120 parts by weight of 3-aminopropyltrimethoxysilane was added to prepare an alkoxysilane mixed solution, and this alkoxysilane mixed solution was stirred for 3 hours to partially condense, and then the weight of isopropyl alcohol and 1-methoxy-2-propanol. It diluted with the mixed solvent of ratio 1: 1. In this liquid, titanium oxide ultrafine particles 15 wt% isopropyl alcohol dispersion (CI Chemical Co., Ltd., average primary particle diameter of ultrafine particles 30 nm) 3179 parts by weight (solid content 476 parts by weight, cured resin 100 parts by weight after curing) On the other hand, 82 parts by weight of ultrafine particles were added and stirred and mixed for 10 minutes to obtain a coating solution 2 for light interference.

Further, in the same manner as in Comparative Example 1, a 20 nm-thick indium tin oxide layer (n _D = 2.10)
0) was deposited. Subsequently, heat treatment was performed at 130 ° C. for 90 minutes to crystallize the indium tin oxide layer.

2.7 Comparative Example 3
A light transmissive conductive film was obtained in the same manner as in Example 1 except that a 10 nm thick SiO ₂ layer was formed and the thickness of the indium tin oxide layer was 29 nm.

  The evaluation results are shown in Table 1 and FIG.

1 Light-transmissive conductive film 11 Light-transmissive support layer (A)
12 Hard coat layer (B)
13 Optical interference layer (C)
14 Light transmissive conductive layer (D)

Claims (4)

(A) a light transmissive support layer;
(B) hard coat layer;
(C) an optical interference layer; and (D) a light transmissive conductive film containing a light transmissive conductive layer,
The hard coat layer (B) is directly disposed on at least one surface of the light transmissive support layer (A),
The light transmissive conductive layer (D) is disposed on at least one of the hard coat layers (B) on the surface opposite to the light transmissive support layer (A) via at least the optical interference layer (C). And a light-transmissive conductive film characterized by satisfying all of the following requirements (1) to (8).
(1) 0.01 <| n _A −n _B | ≦ 0.03
(2) n _D > n _A > n _C
(3) 30 <n _C d _C −0.0025 * (n _D d _D ) ² + 0.7 * (n _D d _D ) <65
(4) 1.35 <n _C <1.55
(5) 5 nm ≦ d _C ≦ 50 nm
(6) 10 nm ≦ d _D ≦ 25 nm
(7) 1 μm ≦ d _B ≦ 10 μm
(8) The total light transmittance is 90% or more (in the above,
n _A represents the refractive index of the light transmissive support layer (A);
n _B represents the refractive index of the hard coat layer (B);
n _C represents the refractive index of the optical interference layer (C);
n _D represents the refractive index of the light-transmissive conductive layer (D);
d _B represents the thickness (μm) of the hard coat layer (B);
d _C is the thickness (nm) of the optical interference layer (C);
d _D is the thickness (nm) of the light transmissive conductive layer (D);
Each is shown. ) The light transmissive conductive film according to claim 1, wherein at least one of the light transmissive conductive layers (D) includes indium tin oxide. The light-transmitting conductive film according to claim 1 or 2, wherein at least one of the optical interference layers (C) includes SiO _x (x = 1 to 2). A capacitive touch panel comprising the light transmissive conductive film according to claim 1.

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