Transparent conductive film

• US 20030071794A1
• Filed: 07/23/2002
• Published: 04/17/2003
• Est. Priority Date: 07/26/2001
• Status: Active Grant

• Current Assignee: Dai Nippon Printing Company Limited
• Original Assignee: Dai Nippon Printing Company Limited
• Inventors: Arakawa, Fumihiro, Suga, Taiji
• Granted Patent: US 6,987,354 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

A transparent conductive film 1 comprises a transparent plastic film 2 and a transparent conductive layer 4 laminated to at least one surface of the transparent plastic film 2. The transparent conductive film 1, as a whole, has a haze value of 8 or less; and at least one of the two surfaces of the transparent plastic film 2, that is, the surface to which the transparent conductive film 4 is laminated and the other surface, is provided with fine irregularities having a maximum height (Rmax) of 0.5 to 2.0 μm. These fine irregularities preferably have a ten-point mean roughness (Rz) of 0.35 to 1.5 μm. The fine irregularities maybe provided as the surface structure of a fine irregularity layer 3 laminated to one surface of the transparent plastic film 2. The transparent conductive layer 4 may be laminated to the surface of the fine irregularity layer 3 formed on the transparent plastic film 2, or to the surface of the transparent plastic film 2 to which the fine irregularity layer 3 is not laminated.

Claims

1. A transparent conductive film comprising:

a transparent plastic film; and

a transparent conductive layer laminated to a surface of the transparent plastic film;

wherein the transparent conductive film, as a whole, has a haze value of 8 or less; and

at least one of the two surfaces of the transparent plastic film, that is, the surface to which the transparent conductive layer is laminated and the other surface, is provided with fine irregularities having a maximum height (Rmax) of 0.5 to 2.0 μ

m.

2. The transparent conductive film according to claim 1, wherein the fine irregularities have a ten-point mean roughness (Rz) of 0.35 to 1.5 μ

m.

3. The transparent conductive film according to claim 1, wherein the fine irregularities are provided as the surface structure of the transparent plastic film.

4. The transparent conductive film according to claim 1, wherein the fine irregularities are provided as the surface structure of a transparent resin layer laminated to the surface of the transparent plastic film.

5. The transparent conductive film according to claim 1, further comprising a hard coat layer laminated to the surface of the transparent plastic film opposite to the surface to which the transparent conductive layer is laminated.

6. The transparent conductive film according to claim 5, wherein the fine irregularities are provided on the surface of the transparent plastic film to which the transparent conductive layer is laminated;

and the other surface of the transparent plastic film to which the hard coat layer is laminated is made smooth so that an exposed surface of the hard coat layer can be a mirror surface.

7. A touch panel comprising:

a first sheet having an electrode layer, and

a second sheet having an electrode layer, arranged on the first sheet with a spacer interposed between the first and second sheets so that the two electrode layers can face each other with an extremely small gap between them;

wherein at least one of the first and second sheets is a transparent conductive film that comprises a transparent plastic film and a transparent conductive layer serving as the electrode layer, laminated to a surface of the transparent plastic film, the transparent conductive film, as a whole, having a haze value of 8 or less, at least one of the two surfaces of the transparent plastic film, that is, the surface to which the transparent conductive layer is laminated and the other surface, being provided with fine irregularities having a maximum height (Rmax) of 0.5 to 2.0 μ

m.

8. The touch panel according to claim 7, wherein the fine irregularities on the transparent conductive film have a ten-point mean roughness (Rz) of 0.35 to 1.5 μ

m.

9. An electroluminescent display panel comprising:

a first sheet having an electrode layer; and

a second sheet having an electrode layer, arranged on the first sheet with a luminescent layer interposed between the first and second sheets so that the two electrode layers can face each other with the luminescent layer between them;

wherein at least one of the first and second sheets is a transparent conductive film that comprises a transparent plastic film and a transparent conductive layer serving as the electrode layer, laminated to a surface of the transparent plastic film, the transparent conductive film, as a whole, having a haze value of 8 or less, at least one of the two surfaces of the transparent plastic film, that is, the surface to which the transparent conductive layer is laminated and the other surface, being provided with fine irregularities having a maximum height (Rmax) of 0.5 to 2.0 μ

m.

10. The electroluminescent display panel according to claim 9, wherein the fine irregularities on the transparent conductive film have a ten-point mean roughness (Rz) of 0.35 to 1.5 μ

m.

11. A process of producing a transparent conductive film, comprising the steps of:

laminating a transparent conductive layer to a surface of a transparent plastic film;

interposing an ionizing-radiation-curing resin between a surface of the transparent plastic film, to which the transparent conductive layer is not laminated, and a die face of a die for providing irregularities, thereby laminating an ionizing-radiation-curing resin layer to this surface of the transparent plastic film;

curing, by application of ionizing radiation, the ionizing-radiation-curing resin layer interposed between the transparent plastic film and the die face of the die for providing irregularities, thereby adhering the ionizing-radiation-curing resin layer to the transparent plastic film; and

separating, from the die for providing irregularities, the cured ionizing-radiation-curing resin layer and the transparent plastic film, the cured ionizing-radiation-curing resin layer being provided with fine irregularities that are the inverse of the irregularities of the die face of the die;

wherein the irregularities of the die face of the die provide, on an exposed surface of the ionizing-radiation-curing resin layer, fine irregularities having a maximum height (Rmax) of 0.5 to 2.0 μ

m.

12. The process according to claim 11, wherein the fine irregularities that are the inverse of the irregularities of the die face of the die have a ten-point mean roughness (Rz) of 0.35 to 1.5 μ

m.

13. A process of producing a transparent conductive film, comprising the steps of:

interposing an ionizing-radiation-curing resin between a surface of a transparent plastic film and a die face of a die for providing irregularities, thereby laminating an ionizing-radiation-curing resin layer to this surface of the transparent plastic film;

curing, by application of ionizing radiation, the ionizing-radiation-curing resin layer interposed between the transparent plastic film and the die face of the die for providing irregularities, thereby adhering the ionizing-radiation-curing resin layer to the transparent plastic film;

separating, from the die for providing irregularities, the cured ionizing-radiation-curing resin layer and the transparent plastic film, the cured ionizing-radiation-curing resin layer being provided with fine irregularities that are the inverse of the irregularities of the die face of the die; and

laminating a transparent conductive layer to at least one of the two surfaces, that is, the surface of the transparent plastic film to which the ionizing-radiation-curing resin layer is not laminated and an exposed surface of the ionizing-radiation-curing resin layer;

wherein the irregularities of the die face of the die provide, on the exposed surface of the ionizing-radiation-curing resin layer, fine irregularities having a maximum height (Rmax) of 0.5 to 2.0 μ

m.

14. The process according to claim 13, where in the fine irregularities that are the inverse of the irregularities of the die face of the die have a ten-point mean roughness (Rz) of 0.35 to 1.5 μ

m.