US4327480A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrically conductive composition, process for making an article using same
Assignee: GSEG LLC
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Filing: 1980-12-12
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Granted: 1982-05-04
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Expires: 2000-12-12
Abstract
Abstract The method of manufacturing, composition and product described herein utilize highly electrically resistive carbon black alone or with low resistivity carbon black to form a self-limiting electrically resistive semi-conductor which presents a positive temperature co-efficient of resistance, the methods which are described providing significantly shortened anneal times, manufacturing ease and reliability.
Inventors
- 👤 Cornelius J. N. Kelly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:56
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/10; H05B3/12; H01; H01B; H01B1/00; H01B1/20; H01B1/24; H01B3/00; H01B3/18; H01B3/30; H01B3/44; H01B5/00; H01B5/16; H01B7/00; H01B7/08; H01B7/0807; H01C; H01C7/00; H01C7/02; H01C7/027; H05B3/40; H05B3/54; H05B3/56; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49083; Y10T29/49099
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
97 words
The method of forming an electrically conductive composition having point-to-point electrical resistance that increases with increasing temperature comprising the steps of (a) uniformly mixing a thermoplastic polymer having at least 20% crystallinity as determined by X-ray diffraction with at least 6% by total weight of the mixture of a high dry resistivity carbon black; (b) forming the desired shape; and (c) thermal structuring that shape by annealing at a temperature at or above the crystalline melting point of the polymer for not more than approximately 8 hours to produce a substantially constant stable room temperature electrical resistance.
Claim 2
Independent Claim
97 words
The method of forming an electrically conductive composition having point-to-point electrical resistance that increases with increasing temperature comprising the steps of (a) uniformly mixing a thermoplastic polymer having at least 20% crystallinity as determined by X-ray diffraction with at least 6% by total weight of the mixture of a high dry resistivity carbon black; (b) forming the desired shape; and (c) thermal structuring that shape by annealing at a temperature at or above the crystalline melting point of the polymer for not more than approximately 8 hours to produce a substantially constant stable room temperature electrical resistance.
Claim 3
Dependent Claim
30 words
The method of claim 1 wherein the mixing step includes the addition of high dry electrical resistance carbon black that is uniformly mixed with said low dry resistivity carbon black.
Claim 4
Dependent Claim
36 words
The method of claim 2 wherein the percentage by weight of the low dry resistivity carbon black and the high dry resistivity carbon black is 20% of the total weight of the mixture with the polymer.
Claim 5
Independent Claim
39 words
The method according to claims 1, 2 or 3 wherein the forming step includes the extruding of the mix onto a pair of elongated electrodes held in spaced apart relation with the extruded mix forming an interconnecting web therebetween.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-05-03 | 1985-11-02 | 1986-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-03 | 1989-11-02 | 1990-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-03 | 1993-11-02 | 1994-05-04 | $7700.00 | Window Closed / Lapsed |