Touch panel

Patent metadata

Field	Value
Publication number	US-9823763-B2
Application number	US-201414158544-A
Country	US
Kind code	B2
Filing date	Jan 17, 2014
Priority date	Jul 19, 2011
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

Provided is a touch panel. The touch panel includes a base and a pressure-sensitive adhesive layer attached to the base and having a peel strength with respect to a polycarbonate sheet of 1,900 g/25 mm or more. The pressure-sensitive adhesive layer includes an acryl polymer compound containing an acryl polymer and a thiol polymer derived by binding a thiol compound into a chain, or a side chain or terminal end of a chain of the acryl polymer. Accordingly, penetration of oxygen, moisture or other impurities at an interface between the base film and the pressure-sensitive adhesive layer, or at an interface between a conductor thin film and a pressure-sensitive adhesive layer may be effectively inhibited, and degradation in optical properties such as visibility due to bubbles generated at a pressure-sensitive adhesive interface may be prevented. In addition, when the pressure-sensitive adhesive layer is directly attached to the conductor thin film and even exposed to severe conditions such as high temperature or high temperature and high humidity, the change in the resistance of the conductor thin film may be effectively inhibited, and thus the touch panel may be stably driven for a long time.

First claim

What is claimed is:

1. A touch panel, comprising:
a base wherein an indium tin oxide (ITO) film is formed on at least one surface of the base; and
a pressure-sensitive adhesive layer directly attached to the indium tin oxide (ITO) film on the base, which comprises an acryl polymer compound containing an acryl polymer derived from an acryl monomer and a thiol polymer derived from an acryl monomer and a thiol compound,
wherein the pressure-sensitive adhesive layer completely covers the ITO film,
wherein the acryl polymer compound has a polydispersity index from 5.0 to 6.9,
wherein the acryl polymer compound has a weight average molecular weight of 630,000 to 2,500,000,
wherein the thiol compound is at least one selected from the group consisting of n-dodecanthiol, t-butyl mercaptan, n-butyl mercaptan, 1-octadecanthiol, trimethylol propane tris(3-mercaptothiol), pentaerythritol tetrakis(3-mercaptopropionate) and glycol dimercaptoacetate,
wherein the pressure-sensitive adhesive layer has a resistance change ratio of the indium tin oxide (ITO) film of 7% or less, and
wherein the pressure-sensitive adhesive layer has a peel strength with respect to a polycarbonate sheet of 2,400 g/25 mm or more.

2. The touch panel according to claim 1 , wherein the acryl polymer comprises a (meth)acrylic acid ester-based monomer in a polymerized form.

3. The touch panel according to claim 1 , wherein the pressure-sensitive adhesive layer further comprises a multifunctional crosslinking agent crosslinking the acryl polymer compound.

4. A pressure-sensitive adhesive composition for a touch panel including a base wherein an indium tin oxide (ITO) film is formed on at least one surface of the base; and a pressure-sensitive adhesive layer directly attached to the indium tin oxide (ITO) film on the base,
wherein the pressure-sensitive adhesive layer completely covers the ITO film, and the pressure-sensitive adhesive layer is formed from the pressure sensitive adhesive composition,
wherein the pressure-sensitive adhesive composition comprises an acryl polymer compound containing an acryl polymer derived from an acryl monomer and a thiol polymer derived from an acryl monomer and a thiol compound,
wherein the acryl polymer compound has a polydispersity index from 5.0 to 6.9,
wherein the acryl polymer compound has a weight average molecular weight of 630,000 to 2,500,000,
wherein the thiol compound is at least one selected from the group consisting of n-dodecanthiol, t-butyl mercaptan, n-butyl mercaptan, 1-octadecanthiol, trimethylol propane tris(3-mercaptothiol), pentaerythritol tetrakis(3-mercaptopropionate) and glycol dimercaptoacetate,
wherein when a pressure-sensitive adhesive layer is formed by using the pressure-sensitive adhesive composition, the layer has a peel strength with respect to a polycarbonate sheet of 2,400 g/25 mm or more, and
wherein the pressure-sensitive adhesive layer has a resistance change ratio of the indium tin oxide (ITO) film of 7% or less.

5. A double-sided pressure-sensitive adhesive tape for a touch panel, comprising a pressure-sensitive adhesive layer which is a cured product of the composition according to claim 4 .

Assignees

• Lg Chemical Ltd

Inventors

• Park Min Soo
• Yang Se Woo
• Chang Suk Ky
• Lee Seung Min

Classifications

• C09J7/0217

  Chemistry & Metallurgy · mapped topic

• G06F3/041

  Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means · CPC title

• C09J133/08 Primary

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C08L41/00

  Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a bond to sulfur or by a heterocyclic ring containing sulfur; Compositions of derivatives of such polymers · CPC title

• C08F220/10

  Esters · CPC title