Polyolefin resin foam sheet and adhesive tape

Patent metadata

Field	Value
Publication number	US-2017292002-A1
Application number	US-201515514097-A
Country	US
Kind code	A1
Filing date	Sep 29, 2015
Priority date	Sep 30, 2014
Publication date	Oct 12, 2017
Grant date	—

Abstract

There is provided a polyolefin resin foam sheet having a plurality of cells which is formed by foaming a polyolefin resin, wherein, in the polyolefin resin foam sheet, the average cell sizes and the maximum cell sizes in the MD direction and the TD direction are each a predetermined value, and a ratio [TD strength at break/MD average cell size] and a ratio [MD strength at break/TD average cell size] are both 80 kPa/μm or more.

First claim

1 . A polyolefin resin foam sheet having a plurality of cells which is formed by foaming a polyolefin resin,
wherein, in the polyolefin resin foam sheet, the average cell sizes in the MD direction and the TD direction are 150 μm or less, and the maximum cell sizes in the MD direction and the TD direction are 500 μm or less; and a ratio of strength at break in the TD direction to the average cell size in the MD direction, [TD strength at break/MD average cell size], and a ratio of strength at break in the MD direction to the average cell size in the TD direction, [MD strength at break/TD average cell size], are both 80 kPa/μm or more.

2 . The polyolefin resin foam sheet according to claim 1 , wherein a ratio of the average cell size in the MD direction to that in the TD direction, [MD average cell size/TD average cell size], is 0.6 to 1.4.

3 . The polyolefin resin foam sheet according to claim 1 , having the withstand voltage value of 8 kV/0.7 mm or more.

4 . The polyolefin resin foam sheet according to claim 1 , having the expansion ratio of 1.1 to 2.8 cm 3 /g.

5 . The polyolefin resin foam sheet according to claim 1 , having the gel fraction of 5 to 60% by mass.

6 . The polyolefin resin foam sheet according to claim 1 , having the thickness of 0.02 to 1.9 mm.

7 . The polyolefin resin foam sheet according to claim 1 , wherein the polyolefin resin is a polyethylene resin.

8 . The polyolefin resin foam sheet according to claim 7 , wherein the polyethylene resin is polymerized with a metallocene polymerization catalyst.

9 . An adhesive tape having a pressure sensitive adhesive layer provided on at least one surface of the polyolefin resin foam sheet according to claim 1 .

Assignees

• Sekisui Chemical Co Ltd

Inventors

• Matsuki Shigeki
• Yachi Koji
• Matsumoto Asami

Classifications

• C09J7/26

  Porous or cellular plastics · CPC title

• C08J2207/02

  Adhesive · CPC title

• B32B27/32

  comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} · CPC title

• B29K2023/12

  PP, i.e. polypropylene · CPC title

• B29K2105/041

  Microporous · CPC title