US3640764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Integral heating elements
Assignee: 3M Co
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Filing: 1968-09-26
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Granted: 1972-02-08
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Expires: 1988-09-26
Abstract
Abstract Combinations are provided of organic binder, metallic particles, or powder converting to a metal under mild reducing conditions, and porcelain enamel frit, preferably in a range of sizes, at least a part of which has average particle diameters which are at least 5 times the diameters of ultimate metal particles. These combinations are used to apply integral heating elements to various utensils.
Inventors
- 👤 Thomas S Shevlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:53
CPC Classifications
A; A47; A47J; A47J27/00; A47J27/004; H; H05; H05B; H05B3/00; H05B3/20; H05B3/22; H05B3/26; H05B3/262; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/26; Y10T428/263
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
40 words
A film according to claim 1 wherein the recrystallizing porcelain enamel frit has particle sizes predominately falling within the ranges in which the average diameter is from 5 to 10 times the average diameter of the particles of conductive powder.
Claim 2
Dependent Claim
53 words
A film according to claim 2 in which the metal-yielding conductive powder is silver oxide with particle size of about 0.5 to 2 microns, the organic binder is polyisobutylene and the porcelain enamel frit iS composed of recrystallizing frit containing titania and is predominately in two sizes of 1-5 microns and 50-105 microns.
Claim 3
Dependent Claim
46 words
A composition adapted to firing to conductive patterns comprising recrystallizing porcelain enamel frit having particles in a range of diameters predominately falling within the range of from about 5-10 up to 50-100 microns and silver oxide having an average diameter of about 0.5 to 2 microns.
Claim 4
Dependent Claim
51 words
A process for production of electrically heated utensil comprising the step of adhering to a utensil coated with porcelain enamel a coating comprising recrystallizing porcelain enamel frit in proportions of from about 85 to about 50 percent of frit and silver oxide in proportions of about 15 to about 50 percent.
Claim 5
Dependent Claim
21 words
A process according to claim 5 wherein the coating is applied in the form of a film containing depolymerizable organic binder.
Claim 6
Dependent Claim
35 words
A process according to claim 6 wherein adhesion of the film is enhanced by application of an adhesive of depolymerizable organic binder in solvent therefor containing 1-10 percent by weight of low-melting lead borosilicate glass.
Claim 7
Dependent Claim
25 words
A process according to claim 7 wherein connection spots are provided by application of metal-rich film over portions of the film where contacts are desired.
Claim 8
Dependent Claim
37 words
As an article of manufacture the combination of a porcelain enameled utensil and an electrically conductive heating element, the fired product of claim 1, bonded to said utensil as an overlay embedded in the porcelain enamel thereof.
Claim 9
Dependent Claim
12 words
A film according to claim 1 in combination with a supporting backing.
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) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |