Adhesive sheet

Patent metadata

Field	Value
Publication number	US-10000668-B2
Application number	US-201415029326-A
Country	US
Kind code	B2
Filing date	Jun 23, 2014
Priority date	Oct 18, 2013
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

[Problem] This is to provide an adhesive sheet having curved surface followability and chemical resistance.
[Means for solving] The adhesive sheet is an adhesive sheet having at least a substrate and an adhesive layer, a load at the time of 5% elongation of the substrate is 15 N/cm or less, a stress relaxation rate of the substrate by elongating to 10%, stopping the elongation at that state and after lapsing 600 seconds is 40% or more and 100% or less, and a chemical weight increased ratio of the substrate is 60% or less.

First claim

The invention claimed is:

1. An adhesive sheet which comprises
a substrate and an adhesive layer,
wherein the substrate consists of a substrate layer containing a urethane-based polymer and a surface protective layer comprising an acrylic-based resin or a fluorine-based resin as an effective ingredient,
the surface protective layer is provided at the outermost surface of the adhesive sheet,
the adhesive layer is directly on the substrate layer, and
a thickness of the substrate layer is 150 μm or more,
wherein the urethane-based polymer is a non-yellowing ester-based thermoplastic polyurethane,
a load at the time of 5% elongation of the substrate is 15 N/cm or less,
a stress relaxation rate of the substrate by elongating to 10%, stopping the elongation at that state and after lapsing 600 seconds is 40% or more and 100% or less, and
a chemical weight increased ratio of the substrate is 60% or less.

2. The adhesive sheet according to claim 1 , wherein the load at the time of 5% elongation of the substrate is 1 N/cm or more and 15 N/cm or less.

3. The adhesive sheet according to claim 1 , wherein a Shore hardness of the substrate layer is 80 A or more and 65 D or less.

4. The adhesive sheet according to claim 1 wherein the acrylic-based resin contains a (meth)acrylic-based polymer having a hydroxyl value of 20 to 120 (KOH mg/g).

5. The adhesive sheet according to claim 1 , wherein the adhesive sheet is used as a protective sheet for protecting the surface of an adherend.

6. The adhesive sheet according to claim 1 wherein the fluorine-based resin contains a fluoroethylene vinyl ether alternating copolymer.

7. The adhesive sheet according to claim 1 wherein the acrylic-based resin is a HALS-hybrid (meth)acrylic-based polymer.

8. The adhesive sheet according to claim 1 , wherein the substrate layer has a thickness of 150 μm to 1 mm.

9. The adhesive sheet according to claim 1 , wherein a thickness of the surface protective layer is 2 to 40 μm.

10. The adhesive sheet according to claim 1 , wherein the surface protective layer is formed by adding a crosslinking agent to a resin for forming the surface protective layer.

11. The adhesive sheet according to claim 10 , wherein the crosslinking agent is at least one selected from the group consisting of an isocyanate-based crosslinking agent and an oxazoline-based crosslinking agent.

12. The adhesive sheet according to claim 1 , wherein the surface protective layer is formed by coating a coating solution for surface protective layer onto the substrate layer.

Assignees

• Nitto Denko Corp

Inventors

• Imoto Eiichi
• Nakagawa Yoshio

Classifications

• C09J2203/306

  for protecting painted surfaces, e.g. of cars · CPC title

• C08L75/06

  from polyesters · CPC title

• C09J133/066

  containing -OH groups · CPC title

• C08G18/6225

  Polymers of esters of acrylic or methacrylic acid · CPC title

• C09J2433/006

  in the substrate · CPC title