US4234439A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dielectric material for influencing electric fields, and stress control devices made therefrom
Assignee: 3M Co
•
Filing: 1979-05-10
•
Granted: 1980-11-18
•
Expires: 1999-05-10
Abstract
Abstract A dielectric composition for influencing electric fields comprising a dielectric base material having electrically conductive and electrically insulating platelet-shaped particles and stress control devices made therefrom.
Inventors
- 👤 Dieter Kehr
- 👤 Juergen Goebell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:51
CPC Classifications
H; H02; H02G; H02G15/00; H02G15/02; H02G15/06; H02G15/064; H02G15/068
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
83 words
A dielectric composition for influencing electric fields comprising a dielectric base material having distributed therein electrically conductive platelet-shaped particles in an amount below a limit concentration at which the composition exhibits an electrical volume resistivity characteristic for insulating materials, and also distributed therein platelet-shaped particles of an insulating material different from said base material and having a higher electrical breakdown voltage than said base material, the number and size of said particles of insulating material being comparable with said platelet-shaped electrically conductive particles.
Claim 2
Dependent Claim
83 words
A dielectric composition for influencing electric fields comprising a dielectric base material having distributed therein electrically conductive platelet-shaped particles in an amount below a limit concentration at which the composition exhibits an electrical volume resistivity characteristic for insulating materials, and also distributed therein platelet-shaped particles of an insulating material different from said base material and having a higher electrical breakdown voltage than said base material, the number and size of said particles of insulating material being comparable with said platelet-shaped electrically conductive particles.
Claim 3
Dependent Claim
26 words
The composition of claim 1, wherein said electrically conductive platelet-shaped particles are arranged in the base material with an essentially random-distributed orientation of their platelet planes.
Claim 4
Dependent Claim
24 words
The composition of claim 1 wherein said insulating material has a relative permittivity which is at least equal to that of the base material.
Claim 5
Dependent Claim
21 words
The composition of claim 1 wherein said base material and said insulating material each have a relative permittivity less than 10.
Claim 6
Dependent Claim
28 words
The composition of claim 1 wherein said insulating material comprises mica platelets in a concentration of from about 5 to about 60 percent by weight of said composition.
Claim 7
Dependent Claim
28 words
The composition of claim 1 wherein said conductive particles comprise aluminum platelets in a concentration of from about 5 to about 30 percent by weight of said composition.
Claim 8
Dependent Claim
26 words
The composition of claim 1 wherein said conductive platelet-shaped particles have a transverse dimension of about 5 to 75 μm when measured transverse of their thickness.
Claim 9
Dependent Claim
28 words
The composition of claim 1 wherein said platelet-shaped particles of insulating material have a transverse dimension of about 15 to 75 μm as measured transverse of their thickness.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-11-18 | 1984-05-19 | 1984-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-18 | 1988-05-19 | 1988-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-18 | 1992-05-19 | 1992-11-18 | $7700.00 | Window Closed / Lapsed |