Electrically conductive material

• US 5,307,233 A
• Filed: 05/28/1991
• Issued: 04/26/1994
• Est. Priority Date: 05/28/1991
• Status: Expired due to Fees

• Current Assignee: Armstrong World Industries Incorporated
• Original Assignee: Armstrong World Industries Incorporated
• Inventors: Forry, John S.
• Primary Examiner(s): Pellinen, A. D.
• Assistant Examiner(s): Fleming, Fritz M.
• Application Number:
  US07/706,358
• Time in Patent Office: 1,064 Days
• Field of Search: 361/212, 361/215, 361/216, 361/220, 156/71, 156/273.9, 156/297, 428/327, 428/379, 428/403, 524/910-914
• US Class Current: 361/220
• CPC Class Codes: H05F 3/025 Floors or floor coverings specially adapted for discharging static charges
• CPC Class Codes: Y10S 524/914 Floor covering compositions
• CPC Class Codes: Y10T 428/254 Polymeric or resinous material

Abstract

A novel product is disclosed comprising a single layer of thermoplastic chips having electrically conductive material coated on the vertical edges of the chips disposed on a continuous electrically conductive support, bonded thereto and to each other and consolidated to form a continuous, electrically conductive sheet.

Claims

1. Electrically conductive sheeting comprising a plurality of polymeric chips of pre-determined shape, each having an upper surface, a lower surface and at least one vertically disposed edge between said surfaces;

an electrically conductive material coating the surface of said vertically disposed edge extending from said upper surface to said lower surface of said chip sufficient to transmit electrostatic charge from the upper surface to the lower surface of the article, said chips arranged as a single layer bonded along the vertically disposed edges to form electrically conductive sheeting.

2. Sheeting as in claim 1 wherein said polymeric chips are filled polyvinyl chloride chips.

3. Sheeting as in claim 1 wherein said electrically conductive material is electrically conductive carbon black.

4. Sheeting as in claim 1 wherein said electrically conductive material is a conductive metal in the form of particles.

5. Sheeting as in claim 1 wherein said vertically disposed edges are metallized.

6. Sheeting as in claim 1 wherein one surface of said sheeting has a continuous electrically conductive coating thereon in electrical contact with said electrically conductive material coating the surface of said vertically disposed edges of said chips of said sheeting.

7. Sheeting as in claim 6 wherein said continuous electrically conductive coating is disposed on a supporting sheet bonded to said one surface of said sheeting.

8. Sheeting as in claim 1 wherein said chips are arranged as a single layer disposed on a continuous support and bonded thereto.

9. A process for manufacturing electrically conductive sheeting which comprises moving a conductively-coated or impregnated support;

beneath the outlet of a chip feeder distributing a single layer of a plurality of thermoplastic chips to substantially cover said moving support, said chips, each having an upper surface, a lower surface, vertically disposed edges coated with an electrically conductive material and the distance between upper and lower surfaces being from about 30 mils to about 90 mils;

adding thermoplastic material onto said layer of chips to fill any void spaces between chips;

heating and applying pressure to consolidate said single layer of chips and said support into electrically conductive sheeting.