Touch panel

• US 20060152640A1
• Filed: 11/30/2005
• Published: 07/13/2006
• Est. Priority Date: 01/11/2005
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Fujii, Shoji, Tanabe, Koji
• Granted Patent: US 7,586,483 B2
• Time in Patent Office: Days
• US Class Current: 349/12
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels

Abstract

A touch panel is equipped with a light-transmissive upper substrate, a light-transmissive lower substrate, a polarizing plate bonded onto a top surface of the upper substrate, and a light-transmissive adhesive layer containing acid acceptors. A lower surface of the upper substrate is formed thereon with an upper conductive layer, and a top surface of the lower substrate is formed thereon with a lower conductive layer facing the upper conductive layer, with a certain air gap provided. The polarizing plate has a polarizer and a triacetylcellulose film bonded onto both surfaces of the polarizer. The adhesive layer bonds at least one of the polarizer with the triacetylcellulose film and the upper substrate with the polarizing plate. This makeup provides the touch panel with favorable visibility and easy operability.

Claims

1. A touch panel comprising:

a light-transmissive upper substrate formed with an upper conductive layer at a lower surface thereof;

a light-transmissive lower substrate formed with a lower conductive layer facing the upper conductive layer with a certain air gap provided, at a top surface thereof;

a polarizing plate bonded onto a top surface of the upper substrate, and including

a polarizer; and

a triacetylcellulose film bonded onto both surfaces of the polarizer; and

a light-transmissive adhesive layer that bonds at least one of the polarizer with the triacetylcellulose film and the upper substrate with the polarizing plate, and that includes acid acceptors.

2. The touch panel as claimed in claim 1,

wherein the adhesive layer includes the acid acceptors by 0.2% to 25% by weight.

3. The touch panel as claimed in claim 1, further comprising:

a retardation plate bonded between a top surface of the upper substrate and the polarizing plate.

4. The touch panel as claimed in claim 1, further comprising:

a light-transmissive cover sheet bonded onto a top surface of the polarizing plate.