Radio wave shielding materials and a method of producing the same

• US 4,576,859 A
• Filed: 10/22/1984
• Issued: 03/18/1986
• Est. Priority Date: 10/21/1983
• Status: Expired due to Fees

• Current Assignee: Bridgestone Corporation
• Original Assignee: Bridgestone Corporation
• Inventors: Fukuda, Hiroya, Oyachi, Tomio, Anami, Masahiko
• Primary Examiner(s): Van Balen, William J.
• Application Number:
  US06/663,657
• Time in Patent Office: 512 Days
• Field of Search: 427/227, 427/244, 427/247, 427/443.1, 428/311.1, 428/311.5, 428/312.2, 428/312.8
• US Class Current: 428/311.11
• CPC Class Codes: H05K 9/0015 Gaskets or seals
• CPC Class Codes: Y10T 428/249962 Void-containing component has a continuous matrix of fibers only [e.g., porous paper, etc.]
• CPC Class Codes: Y10T 428/249967 Inorganic matrix in void-containing component
• CPC Class Codes: Y10T 428/24997 Of metal-containing material

Abstract

A radio wave shielding material and a method of producing the same are disclosed. The radio wave shielding material comprises a plastic foamed body of three-dimensional network skeleton structure, a metal plating coat formed on the skeleton surface, and a coating of conductive rubber and/or plastic formed on the metal plating coat.

Claims

1. A radio wave shielding material comprising a plastic foamed body having a three-dimensional network skeleton structure and provided on its skeleton surface with a metal plating coat, and a coating of a conductive rubber and/or plastic formed on said metal plating coat.

2. A radio wave shielding material according to claim 1, wherein said plastic foamed body is an open-cell polyurethane foam of three-dimensional network skeleton structure having such a porosity that an average cell number per 25 mm of straight line is 10-40 cells.

3. A radio wave shielding material according to claim 1, wherein said plastic foamed body has a volume resistivity of not more than 100 Ω

·

cm.

4. A radio wave shielding material according to claim 1, wherein said metal plating coat is nickel or nickel alloy plating coat.

5. A radio wave shielding material according to claim 1, wherein said metal plating coat has a thickness of not more than 6μ

.

6. A radio wave shielding material according to claim 1, wherein said conductive rubber and/or plastic is selected from conductive silicone rubber, conductive acrylic rubber and modified conductive acrylic rubber.

7. A radio wave shielding material according to claim 1, wherein said coating of conductive rubber and/or plastic has a volume resistivity of not more than 100 Ω

·

cm.

8. A radio wave shielding material according to claim 1, wherein said material is provided on at least one surface with a release paper through a bonding agent locally or wholly applied thereto.

9. A method of producing a radio wave shielding material, which comprises:

forming a metal plating coat on a surface of a plastic foamed body having a three-dimensional network skeleton structure;

impregnating or applying a liquid composition containing a conductive rubber and/or plastic to said plastic foamed body;

subjecting said body to a compression deformation to squeeze out an excess amount of said liquid composition while said metal plating coat is partially broken to provide a proper compression modulus; and

curing said conductive rubber and/or plastic.

10. A method according to claim 9, wherein said metal plating coat is formed by an electroless plating process.

11. A method according to claim 10, wherein said plastic foamed body is subjected to a surface treatment prior to said electroless plating.

12. A method according to claim 9, wherein said compression deformation is a compression strain of 10-90%.