Double-sided pressure-sensitive adhesive sheet and method for sticking and fixing touch panel to display device

• US 7,097,903 B2
• Filed: 02/20/2003
• Issued: 08/29/2006
• Est. Priority Date: 02/21/2002
• Status: Expired due to Fees

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: Kishioka, Hiroaki, Ohura, Masahiro
• Primary Examiner(s): ZIRKER, DANIEL R
• Application Number:
  US10/368,377
• Publication Number:
  US 20030232192A1
• Time in Patent Office: 1,286 Days
• Field of Search: 428/354, 428/343, 428/355.AC, 428/355.RA, 428/356, 428/40.1, 427/208, 427/208.4, 156/306.6, 345/176, 345/173, 385/130, 349/199
• US Class Current: 428/354
• CPC Class Codes: C09J 2301/124 the adhesive layer being present on both sides of the carrier, e.g. double-sided adhesive tape
• CPC Class Codes: C09J 2301/312 parameters being the characterizing feature
• CPC Class Codes: C09J 7/20 characterised by their carriers
• CPC Class Codes: C09J 7/22 Plastics; Metallised plastics
• CPC Class Codes: C09J 7/38 Pressure-sensitive adhesives [PSA]
• CPC Class Codes: C09J 7/385 Acrylic polymers
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 2202/28 Adhesive materials or arrangements
• CPC Class Codes: Y10T 428/14 Layer or component removable to expose adhesive
• CPC Class Codes: Y10T 428/28 Web or sheet containing structurally defined element or component and having an adhesive outermost layer
• CPC Class Codes: Y10T 428/2848 Three or more layers
• CPC Class Codes: Y10T 428/2861 having readily strippable combined with readily readhearable properties [e.g., stick-ons, etc.]
• CPC Class Codes: Y10T 428/2891 including addition polymer from alpha-beta unsaturated carboxylic acid [e.g., acrylic acid, methacrylic acid, etc.] Or derivative thereof

Abstract

A double-sided pressure-sensitive adhesive sheet for fixing a touch panel to a display device wherein one surface of the double-sided pressure-sensitive adhesive sheet is stuck to the surface of the touch panel while the other surface of the double-sided pressure-sensitive adhesive sheet is stuck to a display surface of the display device, the double-sided pressure-sensitive adhesive sheet including: a transparent base; a first transparent pressure-sensitive adhesive layer formed on one surface of the transparent base; and a second transparent pressure-sensitive adhesive layer formed on the other surface of the transparent base; wherein the double-sided pressure-sensitive adhesive sheet is releasable and re-stickable to the display surface while being stuck to the touch panel.

Claims

1. A double-sided pressure-sensitive adhesive sheet for adhering a touch panel to a display surface of a display device, comprising:

a transparent base;

a first transparent pressure-sensitive adhesive layer formed on one surface of said transparent base, said first transparent pressure-sensitive adhesive layer forming a first surface of said double-sided pressure-sensitive adhesive sheet; and

a second transparent pressure-sensitive adhesive layer formed on an opposing surface of said transparent base, said second transparent pressure-sensitive adhesive layer forming a second surface of said double-sided pressure-sensitive adhesive sheet,

wherein said first surface of said double-sided pressure-sensitive adhesive sheet is capable of adhering to substantially an entire surface of the touch panel and said second surface of said double-sided pressure-sensitive adhesive sheet is capable of adhering to substantially an entire surface of a display surface of the display device, and

wherein said second surface of said double-sided pressure-sensitive adhesive sheet is releasable and re-stickable to said display surface of said display device while said first surface of said double-sided pressure-sensitive adhesive sheet is capable of remaining adhered to said touch panel, and

wherein said first transparent pressure-sensitive adhesive layer exhibits 180°

peel adhesion of not lower than 3.5 N/20 mm, at a peeling rate of 300 mm/min, at 23°

C. and to a polyethylene terephthalate film; and

wherein said second transparent pressure-sensitive adhesive layer exhibits 180°

peel adhesion from 0.1 N/20 mm to 3.0 N/20 mm, at a peeling rate of 300 mm/min, at 23°

C. and to a triacetyl cellulose film, and

wherein each of the first and second transparent pressure-sensitive adhesive layers includes an acrylic based pressure-sensitive adhesive agent containing;

an acrylic-based polymer as a main component, the acrylic-based polymer containing (meth)acrylic alkyl ester having an alkyl group with 1 to 18 carbon atoms, and

functional group-containing copolymerizable monomers in the ratio of the amount thereof is not larger than 5% by weight with respect to the total amount of all monomer components; and

a cross linker.

2. A double-sided pressure-sensitive adhesive sheet according to claim 1, wherein said double-sided pressure-sensitive adhesive sheet has a total light ray transmittance of not lower than 90% in a visible wavelength region and has a haze of not higher than 2.0%.