JP2002117724A - Transparent conductive film and touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent conductive film and a touch panel, with high durability, high visibility on a display, and a specific anchor layer especially effective in abrasion resistance and prevention of the generation of sticking. SOLUTION: This transparent conductive film is manufactured by forming an SiOx layer serving as an anchor layer containing a siloxane bond, having center line average roughness whose Ra is 5-20 nm, formed with resin containing fine particles of an average particle size of 1-300 nm on at least one surface of a transparent base film, and forming a transparent conductive layer. This touch panel is manufactured by using the transparent conductive film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent conductive film, and more particularly to a specific film which is applied to a touch panel and the like, has excellent durability and visibility on a display, and is particularly effective for abrasion resistance and prevention of sticking. The present invention relates to a transparent conductive film provided with an anchor layer.

[0002]

2. Description of the Related Art In recent years, a transparent touch panel using a transparent conductive film has been widely used. The transparent touch panel inputs predetermined information and the like to a computer or the like by pressing a predetermined position with a finger or a pen. When input is repeated with a finger or a pen, the resistance value of the transparent conductive film gradually changes and information or the like cannot be input accurately.Also, when pressing a predetermined position with a finger or a pen, a transparent conductive layer of a transparent conductive film, Contact with the opposing transparent conductive layer,
Repeated non-contact causes distortion and the like, which may cause a Newton ring or a problem, or even if a finger or pen is released at the time of contact, the contact does not become non-contact, that is, sticking occurs. There was a problem that it could not withstand use. Therefore, it has been proposed to form a coating layer of an organic resin containing a filler and form a transparent conductive layer thereon. However, when a transparent conductive film is formed via a coating layer of an organic resin containing a filler, there is an effect of preventing Newton's rings, etc., but the adhesion between the coating layer and the transparent conductive film is insufficient, Due to the low film hardness of the resin coating layer, etc., it has poor input durability, especially those with surface roughness exceeding a certain level have problems such as poor scratch resistance, input durability, and solvent resistance. Almost.

[0003]

Accordingly, the present invention provides a transparent conductive material which is excellent in input durability, prevents sticking, is excellent in scratch resistance, is excellent in gas impermeability and is excellent in durability. No film is provided.

[0004]

That is, the present invention provides a transparent base film (A.) having at least one surface having a Ra of 4 to 20 nm formed of a resin containing fine particles having an average particle diameter of 1 to 30 nm. A transparent conductive film comprising an anchor layer (B.) having a center line average roughness, a SiOx layer (S.), and a transparent conductive layer (C.). Is a layer containing a siloxane bond, the transparent conductive film having a thickness of 0.02 to 10 μm, and the transparent conductive film having a SiOx layer (S.) having a thickness of 2 to 25 nm. And a touch panel using these transparent conductive films.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The base film (A.) used in the present invention is not particularly limited, but it is preferable to use a film having high transparency in view of workability and application. Use a resin film such as a cellulose resin such as cellulose acetate or acetate, a polyester resin such as polyethylene terephthalate or polyethylene naphthalate, an acrylic resin such as polymethyl methacrylate, a polycarbonate resin, or a polysulfone resin. Is preferred. The thickness of these films is not particularly limited, but those having a thickness of 12 to 300 μm are preferably used.

[0006] The anchor layer (B.) used in the present invention is not particularly limited in the resin or the like of the layer constitution, but it is preferable that the layer after formation has improved adhesion to a transparent conductive film. Those which contribute to improvement in transparency and have excellent affinity for fine particles are preferable. Constituents such as a resin forming the anchor layer (B.) mainly include a thermosetting resin or an ionizing radiation-curable resin, and are not particularly limited as long as they have the above-mentioned functions, but are not particularly limited, and include melamine resins and acrylates. Alcohol-modified polyfunctional compound, trimethylolpropane acrylate, tripropylene glycol diacrylate, pentaerythritol triacrylate, 1,6-hexanediol acrylate, titanate compound, alkoxysilane hydrolytic condensation resin (siloxane bond-containing resin) Is mentioned. Among them, an alkoxysilane hydrolysis-condensation-based component (siloxane bond-containing resin) can be preferably used. The thickness of the anchor layer (B.) is not particularly limited, but is in the range of 0.02 to 10 μm from the balance between transparency and durability. The ionizing radiation-curable resin is formed from a paint containing at least a resin that is cured by irradiation with an electron beam or ultraviolet rays. Specifically, it contains a photopolymerizable prepolymer, a photopolymerizable monomer, and a photopolymerization initiator, and further contains, if necessary, additives such as a sensitizer, a non-reactive resin, and a leveling agent, and a solvent. It is.

In the present invention, in order to obtain a transparent conductive film having excellent input durability, preventing occurrence of sticking, and having excellent scratch resistance, the center line average roughness of Ra of 4 to 20 nm (JIS B 0601). It is necessary to form an anchor layer (B.) having the following; the Ra is preferably 5 to 10 nm, and for this purpose, an average particle diameter of 1 to 30 to be contained in a component such as a resin.
It is necessary that the average particle diameter of the fine particles of nm is 1 to 30 nm. When Ra is less than 4 nm, the effect of preventing the occurrence of sticking is insufficient. When Ra is more than 20 nm, the effect of preventing the occurrence of sticking is obtained, even if the effect of preventing the occurrence of sticking is obtained. Inferior in

The fine particles used in the present invention include, but are not particularly limited to, silica, silicone resin particles, acrylic resin particles, styrene resin particles, nylon resin particles, and the like. Considering the adhesiveness with the metal oxide sol, a metal oxide sol prepared from a hydrolyzate of a metal alkoxide or the like and in which inorganic oxide fine particles are dispersed in a colloidal form is preferable. More preferably, the colloidally dispersed fine particles are stabilized using a dispersant or the like. Examples of the inorganic oxide fine particles include silicon oxide, antimony oxide, tin oxide, indium oxide, zinc oxide, alumina, titania, and zirconia. Among them, colloidal silica in which silicon oxide is dispersed is preferable in consideration of price and color. In order to enhance the conductive effect of the transparent conductive layer, tin oxide, antimony oxide-tin oxide, or the like can be suitably used. The shape of the particles is preferably spherical or nearly spherical, but is not particularly limited.
The amount of the fine particles to be added is not particularly limited, but is affected by the specific gravity of the fine particles to be used, but is usually in the range of 0.5 to 60% by weight, preferably 5 to 50% by weight of the resin solids.

In the present invention, the SiOx layer (S.) may be provided on the side of the transparent base film (A.) on which the anchor layer (B.) and the transparent conductive layer (C.) are provided, or on the opposite surface. Although it may be provided, it is preferably formed between the anchor layer (B.) and the transparent conductive layer (C.). x is preferably 1.5 to 2.0, and the thickness thereof is preferably 2 to 50 nm, and more preferably 5 to 15 nm. When the thickness is less than 2 nm, the effect of forming the SiOx layer (S.) described later is small, and when it exceeds 50 nm, it is difficult to obtain the effects of post-heat treatment for improving the transparency of the transparent conductive layer (C.). This is not economically feasible. The method for forming the SiOx layer (S.) is not particularly limited, and a known method such as an electron beam evaporation method, a heating evaporation method, or a sputtering method is appropriately selected and adopted. This SiO
By forming the x layer (S.), the transparency of the obtained transparent conductive film is improved, and the film can withstand a pen input or the like.
Further, the deterioration of the transparent conductive layer (C.), which is considered to be due to the water vapor barrier property of the SiOx layer (S.), is suppressed.
Durability also improves. The present invention provides at least one surface of the transparent substrate film (A.)
Ra formed of resin containing fine particles of 30 nm is 4 to 2
An anchor layer (B.) having a center line average roughness of 0 nm,
The transparent conductive film is provided with a SiOx layer (S.) and a transparent conductive layer (C.). An anchor layer (B.) and SiOx are provided on one surface of the transparent base film (A.).
When the layer (S.) and the transparent conductive layer (C.) are sequentially provided,
A hard coat layer may be provided on the other surface of the transparent base film (A.), and an antifouling layer such as a silicon-fluorine type may be provided on the hard coat layer. A.) and another layer may be provided between the anchor layer (B.) and the hard coat layer.

The hard coat layer referred to in the present invention has a pencil hardness of H or more.
Although not particularly limited, a resin thermosetting resin, or an ionizing radiation-curable resin may be mentioned, and a melamine-based resin, an acrylate-based alcohol-modified polyfunctional compound, trimethylolpropane acrylate, tripropylene glycol diacrylate, pentaerythritol triacrylate,
Examples thereof include 1,6-hexanediol acrylate, titanate compounds, and alkoxysilane hydrolysis-condensation resins (siloxane bond-containing resins). For example, as a method for forming a hard coat layer using an ionizing radiation coating, a normal coating method, for example, bar, blade, spin, gravure, spray or the like can be used.

As the transparent conductive layer (C.) in the present invention, a coating layer mainly composed of an inorganic oxide formed by coating a hydrolyzate such as a metal alkoxide, or a CVD, EB evaporation, It is formed by ion plating, sputtering, or the like, and is made of indium-tin (ITO), ZnO2
System, CdO system, SnO2 system and the like are appropriately selected and used. Among them, indium-tin (ITO) is preferable, and those having a tin content of 5 to 15 mol% in the indium-tin (ITO) are particularly preferable. It may be a crystalline one, a crystalline one, or of course, an amorphous-crystalline intermediate (mixed type). The transparent conductive film thus obtained is used in various fields and devices requiring transparent conductivity, but can be suitably used as a transparent electrode of a touch panel.

[0012]

EXAMPLES The present invention will be described in more detail with reference to the following Examples. * Example 1 50 parts of a hexafunctional acrylate monomer, 31 parts of a bifunctional urethane acrylate, 3 parts of a photoinitiator, on one side of a polyethylene terephthalate film having a thickness of 175 μm. Toluene 1
A coating consisting of 00 parts was applied with a Mayer bar so that the thickness of the hard coat resin binder after curing was 3 μm, and after drying the solvent, ultraviolet rays were applied for 300 m with a high pressure mercury lamp.
It was irradiated with J / cm ² and cured to form a hard coat layer (the pencil hardness of the hard coat layer was 2H). On the surface of the polyethylene terephthalate film opposite to the surface on which the hard coat layer is provided, a hydrolyzate of alkoxysilane (the same siloxane bond-containing resin component content as in Example 1),
Mixed solution of cyclohexanone, methyl isobutyl ketone, and an organosilica sol having an average particle diameter of 12 nm (the same siloxane bond-containing resin component content as in Example 1) (solid content ratio, siloxane bond-containing resin component: organosilica sol component = 5) .2: 4.8 weight ratio)
Was applied by a kiss coat to form an anchor layer having a dry thickness of 0.02 μm. Ra of the anchor layer is 7.57 nm.
(Rz: 56.3 nm, measurement range: 500 μm). This anchor coat layer, to form a thin film by 10nm sputtering of SiO _2, to the SiO ₂ thin film, an ITO film as the transparent conductive layer, an indium: tin = 9
A target of 0:10 (metal, molar ratio) was used, the vacuum chamber was set to 10-3 Pa, and a mixed gas of Ar and O2 was introduced to 5 × 10-1 Pa to form a 30 nm thick film by DC sputtering. Heat treatment at ℃ for 24 hours,
A transparent conductive film was obtained. The resistance value of the ITO film of this transparent conductive film was 470 Ω / □, and the total light transmittance was 85.3%. Put the obtained transparent conductive film in 1
The sheet was cut into a size of 0 cm × 15 cm, two pieces of the film were opposed to each other with the ITO film facing each other, the ends were fixed, and the piece was fixed on a glass plate. While pressing with a pressure of 1 kg / cm ^{2 at} the circular end (1 cm ² area),
Drawing was performed at a speed of 0 cm / sec. No sticking (sticking) between the ITO films due to the drawing was observed, no apparent change in the ITO film was observed, and there was no problem in input durability and solvent resistance.

* Example 2 Ra of the anchor layer is 7.12 nm (Rz is 66.3 n)
m, measurement range 500 μm) to obtain a transparent conductive film in the same manner as in Example 1. The obtained transparent conductive film is cut into a size of 10 cm × 15 cm,
The sheets were fixed with the ITO film facing each other and the ends were fixed on a glass plate. From the hard coat layer side of one of the polyethylene terephthalate films, the circular end (1 cm ² area) of the polyacetal resin rod was 1 kg / kg. Drawing was performed at a speed of 10 cm / sec while pressing with a pressure of cm ² . No sticking (sticking) between the ITO films due to this drawing was observed, no apparent change in the ITO film was observed, and there was no problem in input durability and solvent resistance.

Example 3 Ra of the anchor layer is 4.12 nm (Rz is 46.3 n)
m, measurement range 500 μm) to obtain a transparent conductive film in the same manner as in Example 1. The obtained transparent conductive film is cut into a size of 10 cm × 15 cm,
The sheets were fixed with the ITO film facing each other and the ends were fixed on a glass plate. From the hard coat layer side of one of the polyethylene terephthalate films, the circular end (1 cm ² area) of the polyacetal resin rod was 1 kg / kg. Drawing was performed at a speed of 10 cm / sec while pressing with a pressure of cm ² . Although sticking between the ITO films due to the drawing was extremely slight, no apparent change was observed in the ITO film, and there was no problem in input durability and solvent resistance.

* Example 4 On one side of a polyethylene terephthalate film having a thickness of 175 μm, 50 parts of a 6-functional acrylate monomer, 31 parts of a bifunctional urethane acrylate, 3 parts of a photoinitiator, and 1 part of toluene
A coating consisting of 00 parts was applied with a Mayer bar so that the thickness of the hard coat resin binder after curing was 3 μm, and after drying the solvent, ultraviolet rays were applied for 300 m with a high pressure mercury lamp.
It was irradiated with J / cm ² and cured to form a hard coat layer (the pencil hardness of the hard coat layer was 2H). On a surface of the polyethylene terephthalate film opposite to the surface on which the hard coat layer is provided, a hydrolyzate of alkoxysilane (28.5% by weight of a siloxane bond-containing resin component), cyclohexanone, methyl isobutyl ketone, and an average particle diameter of 12
A mixture liquid (solid content ratio, siloxane bond-containing resin component: organosilica sol component = 4: 1 weight ratio) of an organosilica sol methyl isobutyl ketone dispersion liquid (30 wt% of an organosilica sol component) having a thickness of 4 nm is applied by a kiss coat and dried. An anchor layer of 0.03 μm was formed. Ra of the anchor layer is 9.62 nm (Rz (JIS B 0601).
84.1 nm, measurement range 500 μm.
m). On this anchor coat layer, a thin film of SiO ₂ was formed by sputtering to a thickness of 10 nm.
On the O ₂ thin film, an ITO film as a transparent conductive layer, a target of indium: tin = 90: 10 (oxide, molar ratio) is used, the vacuum chamber is set to 10-3 Pa, and a mixed gas of Ar and O 2 is introduced. Then, the film was formed to a thickness of 30 nm by DC sputtering at 5 × 10 -1 Pa to obtain a transparent conductive film. The resistance value of the ITO film of this transparent conductive film was 257 Ω / □, and the total light transmittance was 84.9%. The obtained transparent conductive film is 10 cm × 15 cm.
The two pieces are cut so that the ITO film faces each other, the ends are fixed, and they are fixed on a glass plate. The circular end of the polyacetal resin rod from the hard coat layer side of one of the polyethylene terephthalate films Drawing was performed at a speed of 10 cm / sec while applying a pressure of 1 kg / cm ² (1 cm ² area). No sticking (sticking) between the ITO films due to this drawing was observed.
No apparent change in the film was observed, and there was no problem in input durability and solvent resistance.

Comparative Example 1 On one side of a polyethylene terephthalate film having a thickness of 175 μm, 50 parts of a hexafunctional acrylate monomer, 31 parts of a bifunctional urethane acrylate, 3 parts of a photoinitiator, and 1 part of toluene
A coating consisting of 00 parts was applied with a Mayer bar so that the thickness of the hard coat resin binder after curing was 3 μm, and after drying the solvent, ultraviolet rays were applied for 300 m with a high pressure mercury lamp.
It was irradiated with J / cm ² and cured to form a hard coat layer (the pencil hardness of the hard coat layer was 2H). On a surface of the polyethylene terephthalate film opposite to the surface on which the hard coat layer is provided, a mixed solution of 1 kg of a hydrolyzate of an alkoxysilane (a resin component containing a siloxane bond), 1 kg of cyclohexanone, and 5 kg of methyl isobutyl ketone (containing a siloxane bond). (Resin component 4.0%, organosilica sol 0%) is applied by a kiss coat to a dry thickness of 25%.
A nm anchor layer was formed. Ra of the anchor layer is 2.90 nm (Rz is 23.0 nm, measurement range 500
μm). On this anchor coat layer, an ITO film was used as a transparent conductive layer, and a target of indium: tin = 90: 10 (oxide, molar ratio) was used.
-3 Pa and 5 while introducing a mixed gas of Ar and O2.
× 10-1Pa and 30n thickness by DC sputtering
m to obtain a transparent conductive film. The resistance value of the ITO film of this transparent conductive film was 275 Ω / □, and the total light transmittance was 84.2%. The obtained transparent conductive film is cut into a size of 10 cm × 15 cm, and two films are opposed to each other with the ITO film facing each other, the ends are fixed, and the film is fixed on a glass plate, and a hard coat of one polyethylene terephthalate film is formed. Drawing was performed at a speed of 10 cm / sec while pressing with a pressure of 1 kg / cm ² at the circular end (1 cm ² area) of the polyacetal resin rod from the layer side. Due to this drawing, sticking (sticking) between the ITO films was observed, and the film did not return to a non-contact state, and a part of the ITO film was found to be damaged.

[0017]

The transparent conductive film of the present invention, when used in a touch panel or the like, has excellent scratch resistance, excellent input durability, and can prevent the occurrence of sticking (without sticking between ITO films). It was a conductive film.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // C08L 101: 00 C08L 101: 00 F term (Reference) 4F006 AA02 AA35 AA36 AB39 AB54 BA01 CA08 DA04 4F100 AA20C AA33 AK01B AK25 AK42 AK52B AR00A AR00D BA04 BA05 BA10A BA10D BA25B BA25C CA23B DD07B DE01B EH66C GB41 JG01D JK14 JK15B JN01A JN01D YY00B YY00C 5B087 AA04 CC14 CC36 5G307 FC02 FB01

Claims (4)

[Claims] 1. An anchor layer having a center line average roughness of Ra of 4 to 20 nm formed of a resin containing fine particles having an average particle diameter of at least 1 to 30 nm on at least one surface of a transparent base film (A.). B.), SiOx layer (S.),
A transparent conductive film provided with a transparent conductive layer (C.). 2. The transparent conductive film according to claim 1, wherein the anchor layer (B.) is a layer containing a siloxane bond, and has a thickness of 0.02 to 10 μm. 3. The thickness of the SiOx layer (S.) is 2 to 25 n.
2. The transparent conductive film according to claim 1, wherein m is m. 4. A touch panel using the transparent conductive film according to claim 1.