Patent US4552035A successfully refreshed from Google Patents.
US4367168A
Expired / Lapsed
US
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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: 1983-01-04
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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
2026-11-02 13:55
CPC Classifications
H; H01; H01B; H01B7/00; H01B7/08; H01B7/0807; H01B1/00; H01B1/20; H01B1/24; H01B5/00; H01B5/16; H01C; H01C7/00; H01C7/02; H01C7/027; H05; H05B; H05B3/00; H05B3/10; H05B3/12; H05B3/40; H05B3/54; H05B3/56
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
128 words
An electrically conductive composition having point-to-point electrical resistance that increases with increasing temperature comprising a mixture of carbon black having high dry electrical resistivity and a crystalline polymer, the carbon black being substantially uniformly dispersed in said polymer, said polymer having at least 20% crystallinity as determined by X-ray diffraction, the percentage by weight of said high electrical resistivity carbon black based upon the total weight of said mixture being at least 6%, said mixture of high dry resistivity carbon black and polymer being substantially non-conductive upon initial mixing and before annealing, the composition having been annealed at a temperature equal to or above the crystalline melting point of the polymer for a period of time sufficient to produce a substantially constant and stable room temperature electrical resistance.
Claim 2
Dependent Claim
128 words
An electrically conductive composition having point-to-point electrical resistance that increases with increasing temperature comprising a mixture of carbon black having high dry electrical resistivity and a crystalline polymer, the carbon black being substantially uniformly dispersed in said polymer, said polymer having at least 20% crystallinity as determined by X-ray diffraction, the percentage by weight of said high electrical resistivity carbon black based upon the total weight of said mixture being at least 6%, said mixture of high dry resistivity carbon black and polymer being substantially non-conductive upon initial mixing and before annealing, the composition having been annealed at a temperature equal to or above the crystalline melting point of the polymer for a period of time sufficient to produce a substantially constant and stable room temperature electrical resistance.
Claim 3
Dependent Claim
16 words
The composition of claim 1 wherein said composition is provided with a form-sustaining electrically insulating enclosure.
Claim 4
Dependent Claim
155 words
An electrically conductive composition having point-to-point electrical resistance that increases with increasing temperature comprising a mixture of high dry electrical resistivity carbon black, low dry electrical resistivity carbon black, and a crystalline polymer, the carbon blacks being substantially uniformly dispersed in said polymer, said polymer having at least 20% crystallinity as determined by X-ray diffraction, the percentage by weight of said high electrical resistivity carbon black based upon the total mixture weight being at least 6%, the remainder of the total weight of the carbon blacks being low electrical resistivity carbon black in an amount providing the desired point-to-point resistance said mixture of high dry resistivity carbon black and polymer being substantially non-conductive upon initial mixing and before annealing, said composition having been annealed at a temperature equal to or above the crystalline melting point of the polymer for a period of time sufficient to produce a substantially constant and stable room temperature electrical resistance.
Claim 5
Dependent Claim
155 words
An electrically conductive composition having point-to-point electrical resistance that increases with increasing temperature comprising a mixture of high dry electrical resistivity carbon black, low dry electrical resistivity carbon black, and a crystalline polymer, the carbon blacks being substantially uniformly dispersed in said polymer, said polymer having at least 20% crystallinity as determined by X-ray diffraction, the percentage by weight of said high electrical resistivity carbon black based upon the total mixture weight being at least 6%, the remainder of the total weight of the carbon blacks being low electrical resistivity carbon black in an amount providing the desired point-to-point resistance said mixture of high dry resistivity carbon black and polymer being substantially non-conductive upon initial mixing and before annealing, said composition having been annealed at a temperature equal to or above the crystalline melting point of the polymer for a period of time sufficient to produce a substantially constant and stable room temperature electrical resistance.
Claim 6
Dependent Claim
16 words
The composition of claim 3 wherein the mixture is provided with an electrically insulating, form-sustaining enclosure.
Claim 7
Dependent Claim
27 words
The electrically conductive composition of claim 3 wherein the percentage by weight of both carbon blacks relative to the total weight of the mixture is about 20%.
Claim 8
Dependent Claim
37 words
The electrically conductive composition of claim 5 wherein the amount of high dry electrical resistivity carbon black in excess of 6% and the amount of low dry resistivity carbon black is determined by the desired point-to-point resistance.
Claim 9
Dependent Claim
42 words
The composition of claims 5 or 6 wherein the composition has been annealed at a temperature equal to or above the crystalline melting point of the polymer for a period of time sufficient to produce a substantially constant stable room temperature resistance.
Claim 10
Dependent Claim
18 words
The composition of claims 5 or 6 wherein the mixture is provided with a form-sustaining electrically insulating enclosure.
Claim 11
Dependent Claim
16 words
The composition of claim 7 wherein the mixture is provided with a form-sustaining electrically insulating enclosure.
References Cited (Backward Citations)
US3412358A
Cited
US3435401A
Cited
US3900654A
Cited
US3861021A
Cited
US3793716A
Cited
US3914363A
Cited
US3823217A
Cited
US4177446A
Cited
US4169816A
Cited
US4237441A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-01-03 | 1986-07-05 | 1987-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-03 | 1990-07-05 | 1991-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-03 | 1994-07-05 | 1995-01-04 | $7700.00 | Window Closed / Lapsed |