US3761047A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mold coating
Assignee: GNB Inc
•
Filing: 1971-08-09
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Granted: 1973-09-25
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Expires: 1991-08-09
Abstract
Abstract A coating for the internal cavity of a mold for forming objects such as battery grids and the like including a perfluorocarbon film (e.g., - tetrafluoroethylene) having dispersed therein heatinsulating particles (e.g., - talc). The thickness of the film and the size and amount of the heat-insulating particles are maintained within defined limits to allow formation of complete grids with easy release from the mold.
Inventors
- 👤 G Mao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:22
CPC Classifications
B; B22; B22C; B22C3/00; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/29
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
167 words
In a mold for forming objects from a molten fluid having mating sections defining an internal cavity conforming to the object shape and a gate area to receive and channel the molten fluid to the internal cavity, the mating sections being capable of parting to allow the formed objects to be removed from the cavity, the improvement which comprises a perfluorocarbon coating of from about 1.5 to 3.5 mils in thickness covering at least the internal cavity and having dispersed therein from about 10 to 40 percent, by volume, of heat-insulating particles with a size of from about 10 to 80 microns, the heat-insulating property of the particles being sufficient to delay solidification of the molten fluid until the fluid has at least substantially filled the cavity and the heat-insulating particles being sized to provide the coating surface with a roughness allowing the air in the internal cavity to escape as the molten fluid passes therethrough yet not substantially impairing the surface of the object being formed.
Claim 2
Dependent Claim
167 words
In a mold for forming objects from a molten fluid having mating sections defining an internal cavity conforming to the object shape and a gate area to receive and channel the molten fluid to the internal cavity, the mating sections being capable of parting to allow the formed objects to be removed from the cavity, the improvement which comprises a perfluorocarbon coating of from about 1.5 to 3.5 mils in thickness covering at least the internal cavity and having dispersed therein from about 10 to 40 percent, by volume, of heat-insulating particles with a size of from about 10 to 80 microns, the heat-insulating property of the particles being sufficient to delay solidification of the molten fluid until the fluid has at least substantially filled the cavity and the heat-insulating particles being sized to provide the coating surface with a roughness allowing the air in the internal cavity to escape as the molten fluid passes therethrough yet not substantially impairing the surface of the object being formed.
Claim 3
Dependent Claim
11 words
The coated mold of claim 1 wherein the perfluorocarbon is polytetrafluoroethylene.
Claim 4
Dependent Claim
29 words
The coated mold of claim 1 wherein the heat-insulating particles are formed of a member selected from the group consisting of talc, silica, alumina, diatomaceous earth and cork dust.
Claim 5
Dependent Claim
12 words
The coated mold of claim 3 wherein the heat-insulating particles are talc.
Claim 6
Dependent Claim
13 words
The coated mold of claim 3 wherein the heat-insulating particles are cork dust.
Claim 7
Dependent Claim
23 words
The coated mold of claim 1 wherein the heat-insulating particles are present in an amount of at least about 25 percent, by volume.
Claim 8
Dependent Claim
214 words
In a mold for forming objects from a molten fluid having mating sections defining an internal cavity conforming to the object shape and a gate area to receive and channel the molten fluid to the internal cavity, the mating sections being capable of parting to allow the formed object to be removed from the cavity, the improvement which comprises a first perfluorocarbon coating of from about 0.5 to about 1 mil in thickness covering at least the internal cavity and having dispersed therein from about 5 to 30% by volume of heat-inSulating particles with a size of from about 10 to 80 microns, a second perfluorocarbon coating of about 1.5 to 2.5 mils covering the first coating and having dispersed therein from about 10 to about 10% by volume of heat-insulating particles with a size of about 10 to 80 microns, the heat-insulating property of the particles of the two coatings being sufficient to delay solidification of the molten fluid until the fluid has at least substantially filled the cavity and the heat insulating particles being sized to provide the surface of the second coating with a roughness allowing the air in the internal cavity to escape as the molten fluid passes therethrough yet not substantially impairing the surface of the object being formed.
Claim 9
Dependent Claim
214 words
In a mold for forming objects from a molten fluid having mating sections defining an internal cavity conforming to the object shape and a gate area to receive and channel the molten fluid to the internal cavity, the mating sections being capable of parting to allow the formed object to be removed from the cavity, the improvement which comprises a first perfluorocarbon coating of from about 0.5 to about 1 mil in thickness covering at least the internal cavity and having dispersed therein from about 5 to 30% by volume of heat-inSulating particles with a size of from about 10 to 80 microns, a second perfluorocarbon coating of about 1.5 to 2.5 mils covering the first coating and having dispersed therein from about 10 to about 10% by volume of heat-insulating particles with a size of about 10 to 80 microns, the heat-insulating property of the particles of the two coatings being sufficient to delay solidification of the molten fluid until the fluid has at least substantially filled the cavity and the heat insulating particles being sized to provide the surface of the second coating with a roughness allowing the air in the internal cavity to escape as the molten fluid passes therethrough yet not substantially impairing the surface of the object being formed.
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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) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |