Touch panel and method of manufacturing the same

• US 20040257344A1
• Filed: 05/28/2004
• Published: 12/23/2004
• Est. Priority Date: 06/18/2003
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Matsumoto, Kenichi, Murakami, Tetsuo, Fukui, Toshiharu
• Granted Patent: US 7,633,565 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

Upper substrate 1 that has upper conductive layer 2 formed on a bottom surface thereof is bonded to lower substrate 3 that has lower conductive layer 4 opposed to upper conductive layer 2 with a predetermined space held therebetween on a top surface of lower substrate 3 by adhesive layer 15 that is made of a thermoplastic resin containing a tackifier dispersed therein and bonding property of the adhesive layer is enhanced by pressing. Addition of the tackifier increases flexibility of adhesive layer 15 and performs bonding with a large adhesive area at pressing. Thus, the width of adhesive layer 15 can be as small as approximately 1 to 1.5 mm. This can provide a smaller touch panel ensuring a predetermined touch sensitive area.

Claims

1. A touch panel comprising:

an upper substrate having an upper conductive layer formed on a bottom surface thereof;

a lower substrate having a lower conductive layer formed thereon, the lower conductive layer opposed to the upper conductive layer with a predetermined space held therebetween; and

an adhesive layer bonding the upper substrate and the lower substrate;

wherein the adhesive layer is made of an adhesive material, and the adhesive material includes a thermoplastic resin and a tackifier, and bonding property of the adhesive material is enhanced by pressing.

2. The touch panel of claim 1, wherein the adhesive layer is 1.0 to 1.5 mm wide.

3. The touch panel of claim 1, wherein the adhesive layer is 5 to 50 μ

m thick.

4. The touch panel of claim 1, wherein the adhesive layer has an elastic modulus ranging from 10³ to 10⁸ Pa.

5. The touch panel of claim 1, wherein the thermoplastic resin is selected from at least one of acrylic resin and polyester resin.

6. The touch panel of claim 1, wherein the tackifier is a thermoplastic oligomer, and the adhesive material contains 1 to 35 gram of the-tackifier in 100 gram of the thermoplastic resin.

7. The touch panel of claim 1, wherein the adhesive material contain 1 to 20 gram of an isocyanate-containing curing agent dispersed in 100 gram of the thermoplastic resin.

8. The touch panel of claim 1, wherein the adhesive layer is 1.0 to 1.5 mm wide, and 5 to 50 μ

m thick;

the thermoplastic resin contains at least one of acrylic resin and polyester resin;

the tackifier is a thermoplastic oligomer;

the adhesive material contains 1 to 35 gram of the tackifier in 100 gram of the thermoplastic resin; and

the adhesive layer has an elastic modulus ranging from 10³ to 10⁸ Pa.

9. A method of manufacturing a touch panel, the touch panel comprising:

an upper substrate having an upper conductive layer formed on a bottom surface thereof;

a lower substrate having a lower conductive layer formed thereon, the lower conductive layer opposed to the upper conductive layer with a predetermined space held therebetween; and

an adhesive layer bonding the upper substrate and the lower substrate;

wherein the adhesive layer is made of an adhesive material, and the adhesive material includes a thermoplastic resin and a tackifier, and bonding property of the adhesive material is enhanced by pressing;

the method comprising the steps of;

printing the adhesive layer on at least one of the upper substrate and the lower substrate;

opposing the upper substrate to the lower substrate; and

bonding the upper substrate and the lower substrate by pressing the adhesive layer.

10. The method of manufacturing a touch panel of claim 9, wherein

the thermoplastic resin contains at least one of acrylic resin and polyester resin;

the tackifier is a thermoplastic oligomer; and

the adhesive material contains 1 to 35 gram of the tackifier in 100 gram of the thermoplastic resin.

11. The method of manufacturing a touch panel of claim 10, wherein the adhesive material is made by dispersing 1 to 20 gram of an isocyanate-containing curing agent in 100 gram of the thermoplastic resin.