Display unit integral with touch panel bonded through an adhesive composition or an adhesive film and production method thereof

• US 6,310,612 B1
• Filed: 12/23/1998
• Issued: 10/30/2001
• Est. Priority Date: 12/24/1997
• Status: Expired due to Fees

• Current Assignee: Bridgestone Corporation
• Original Assignee: Bridgestone Corporation
• Inventors: Sakurai, Ryo, Kotsubo, Hidefumi, Kitano, Tetsuo, Morimura, Yasuhiro, Matsuse, Takahiro
• Primary Examiner(s): Wilson, Donald R.
• Application Number:
  US09/220,577
• Time in Patent Office: 1,042 Days
• Field of Search: 345/173, 178/18.03
• US Class Current: 345/173
• CPC Class Codes: C08L 2666/28 Non-macromolecular organic substances
• CPC Class Codes: C09J 123/08 Copolymers of ethene C09J123/16 takes precedence
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means

Abstract

A heat- and/or photo-curing adhesive composition to be used in production of a display unit integral with a touch panel by bonding the touch panel to the display unit, the adhesive composition comprising as a main component of one or more than one kind of copolymer selected from (1) ethylene-vinyl acetate copolymer; (2) copolymer of ethylene, vinyl acetate, and acrylate and/or methacrylate monomer; (3) copolymer of ethylene, vinyl acetate, and maleic acid and/or maleic anhydride; and (4) copolymer of ethylene, acrylate and/or methacrylate monomer, and maleic acid and/or maleic anhydride.

Claims

1. A display unit integral with a touch panel which is characterized in that the touch panel and the display unit are bonded together by a heat- or photo-cured layer of an adhesive composition comprising as a main component at least one copolymer selected from the group consisting of:

(1) an ethylene-vinyl acetate copolymer;

(2) a copolymer of ethylene, vinyl acetate, and acrylate and/or methacrylate monomer;

(3) a copolymer of ethylene, vinyl acetate, and maleic acid and/or maleic anhydride; and

(4) a copolymer of ethylene, acrylate and/or methacrylate monomer, and maleic acid and/or maleic anhydride.

2. The display unit of claim 1, wherein said at least one copolymer of the adhesive composition is at least one copolymer selected from the group consisting of:

(1) an ethylene-vinyl acetate copolymer in which the content of vinyl acetate units is 10-50% by weight;

(2) a copolymer of ethylene, vinyl acetate, and acrylate and/or methacrylate monomer in which the content of vinyl acetate units is 2-50% by weight and the content of acrylate and/or methacrylate units is 0.01-20% by weight;

(3) a copolymer of ethylene, vinyl acetate, and maleic acid and/or maleic anhydride in which the content of vinyl acetate units is 10-50% by weight and the content of maleic acid and/or maleic anhydride units is 0.01-10% by weight; and

(4) a copolymer of ethylene, acrylate and/or methacrylate monomer, and maleic acid and/or maleic anhydride in which the content of acrylate and/or methacrylate units is 1-50% by weight and the content of maleic acid and/or maleic anhydride units is 0.01-10% by weight.

3. The display unit of claim 1, wherein said layer of an adhesive composition comprises a film having a thickness of from 50 to 1000 μ

m.

4. The display unit of claim 3, wherein said film has an average surface roughness Ra of 0.1-20 μ

m due to embossing one or both sides thereof.

5. The display unit of claim 3, wherein said display unit integral with the touch panel is made by a process comprising interposing said film between the touch panel and the display unit, and then curing the adhesive composition by heat and/or light.

6. The display unit of claim 4, wherein said display unit integral with the touch panel is made by a process comprising interposing said film between the touch panel and the display unit, and then melting and curing simultaneously said adhesive composition by heating under reduced pressure.

7. The display unit of claim 4, wherein said display unit integral with the touch panel is made by a process comprising interposing said film between the touch panel and the display unit, and then melting and curing simultaneously said adhesive composition by heating under pressure.

8. A process for producing a display unit integral with a touch panel, said process comprising interposing an adhesive composition between the touch panel and the display unit, and then curing the adhesive composition by heat and/or light,

wherein said adhesive composition comprises as a main component at least one copolymer selected from the group consisting of:

(1) an ethylene-vinyl acetate copolymer;

(2) a copolymer of ethylene, vinyl acetate, and acrylate and/or methacrylate monomer;

(3) a copolymer of ethylene, vinyl acetate, and maleic acid and/or maleic anhydride; and

(4) a copolymer of ethylene, acrylate and/or methacrylate monomer, and maleic acid and/or maleic anhydride.

9. A process for producing a display unit integral with a touch panel, said process comprising interposing an adhesive film between the touch panel and the display unit, and then melting and curing said adhesive film by heating under reduced pressures,

wherein said adhesive film has an average surface roughness Ra of 0.1-20 μ

m due to embossing one or both sides thereof and said adhesive film is made from an adhesive composition comprising as a main component at least one copolymer selected from the group consisting of;

(1) an ethylene-vinyl acetate copolymer;

(2) a copolymer of ethylene, vinyl acetate, and acrylate and/or methacrylate monomer;

(3) a copolymer of ethylene, vinyl acetate, and maleic acid and/or maleic anhydride; and

(4) a copolymer of ethylene, acrylate and/or methacrylate monomer, and maleic acid and/or maleic anhydride.

10. A process for producing a display unit integral with a touch panel, said process comprising interposing an adhesive film between the touch panel and the display unit, and then melting and curing said adhesive film by heating under pressure,

wherein said adhesive film has an average surface roughness Ra of 0.1-20 μ

m due to embossing one or both sides thereof and said adhesive film is made from an adhesive composition comprising as a main component at least one copolymer selected from the group consisting of;

(1) an ethylene-vinyl acetate copolymer;

(2) a copolymer of ethylene, vinyl acetate, and acrylate and/or methacrylate monomer;

(3) a copolymer of ethylene, vinyl acetate, and maleic acid and/or maleic anhydride; and

(4) a copolymer of ethylene, acrylate and/or methacrylate monomer, and maleic acid and/or maleic anhydride.