US3618753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Large flake reconstituted mica insulation
Assignee: 3M Co
•
Filing: 1968-09-17
•
Granted: 1971-11-09
•
Expires: 1988-09-17
Abstract
Abstract A reconstituted mica insulation sheet comprising large mica flakes has improved physical properties, particularly resistance to cut-through and sever mechanical abuse without danger of electrical failure. The sheet can be impregnated with resin, laminated to webs, adhesive-coated, slit, and coiled to form insulating tapes.
Inventors
- 👤 David W Glasspoole
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:14
CPC Classifications
H; H01; H01B; H01B3/00; H01B3/02; H01B3/04; Y; Y10; Y10S; Y10S428/00; Y10S428/906; Y10S428/91; Y10T; Y10T428/00; Y10T428/25; Y10T428/251; Y10T428/29; Y10T428/2911; Y10T428/31504; Y10T428/31652; Y10T428/31663; Y10T428/31667; Y10T428/31786; Y10T428/31797
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
9 words
The insulation sheet of claim 1 impregnated with resin.
Claim 2
Dependent Claim
26 words
The insulation sheet of claim 2 wherein the resin selected from the class consisting of epoxy resin, polyester resin, silicone resin, alkyd resin, and acrylic resin.
Claim 3
Dependent Claim
11 words
The insulating sheet of claim 3 laminated to a fibrous web.
Claim 4
Dependent Claim
11 words
The laminate of claim 4 wherein the web is polyethylene terephthalate.
Claim 5
Dependent Claim
11 words
The insulation sheet of claim 3 laminated to a polymeric film.
Claim 6
Dependent Claim
14 words
The laminate of claim 6 wherein the polymeric film is biaxially oriented polyethylene terephthalate.
Claim 7
Dependent Claim
67 words
As a new article of commerce, an insulating tape wound convolutely upon itself in roll form and capable of being unwound therefrom without delaminating or offsetting, said tape comprising the insulation sheet of claim 1 or 2 laminated to one side of a thin flexible web, whereby said insulating tape has increased specific gravity, excellent tensile strength, outstanding electrical properties, and resistance to cut-through and physical abuse.
Claim 8
Dependent Claim
20 words
The tape of claim 8 wherein the insulation sheet has a second thin flexible web laminated on its other side.
References Cited (Backward Citations)
US2739638A
Cited
US3001571A
Cited
US3131114A
Cited
US3117900A
Cited
US3101845A
Cited
US3226286A
Cited
US3215590A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |