US3929947A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for manufacturing wallboard and the like
Assignee: United States Department of the Interior
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Filing: 1974-08-08
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Granted: 1975-12-30
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Expires: 1994-08-08
Abstract
Abstract A process for manufacturing wallboard and the like comprising a basic composition of sulfur and gypsum wherein sulfur is foamed by the vaporization of the water contained in the gypsum, thereby producing a stable foam that may be compressed under pressure between sheets of wallboard covering material.
Inventors
- 👤 Murray Arthur Schwartz
- 👤 Thomas Oscar Llewellyn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:52
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/18; B32B5/20; C; C04; C04B; C04B28/00; C04B28/36; B32B29/00; B32B29/002; B32B29/007; B32B38/00; B32B2038/0052; B32B2038/0084; B32B2607/00; B32B2607/02; Y; Y10; Y10S; Y10S264/00; Y10S264/05; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249967
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
60 words
A PROCESS FOR MAKING POROUS WALLBOARD PANELS AND RELATED POROUS BUILDING MATERIALS COMPRISING THE STEPS OF: A. PROVIDING A MAJOR QUANTITY OF MOLTEN SULFUR AT A TEMPERATURE OF ABOUT 130* TO 155*C, B. ADDING A MINOR AMOUNT OF GYPSUM CASO4,2H2O, TO THE MOLTEN SULFUR IN SUFFICIENT QUANTITY SUCH THAT THE WATER IN THE GYPSUM VAPORIZES, THEREBY TRANSFORMING THE GYPSUM INTO
Claim 2
Dependent Claim
60 words
A PROCESS FOR MAKING POROUS WALLBOARD PANELS AND RELATED POROUS BUILDING MATERIALS COMPRISING THE STEPS OF: A. PROVIDING A MAJOR QUANTITY OF MOLTEN SULFUR AT A TEMPERATURE OF ABOUT 130* TO 155*C, B. ADDING A MINOR AMOUNT OF GYPSUM CASO4,2H2O, TO THE MOLTEN SULFUR IN SUFFICIENT QUANTITY SUCH THAT THE WATER IN THE GYPSUM VAPORIZES, THEREBY TRANSFORMING THE GYPSUM INTO
Claim 3
Dependent Claim
45 words
The process of claim 1 further including the step of adding a viscosity increasing agent from the group consisting of P2S5 and styrene and an inert material from the group consisting of talc and clay to the molten sulfur prior to the addition of gypsum.
Claim 4
Dependent Claim
31 words
The process of claim 1 wherein the foamed sulfur is formed under pressure between two sheets of covering material which become adhesively laminated to the formed panel after the cooling thereof.
Claim 5
Dependent Claim
24 words
The process of claim 1 wherein the formed panel increases in density from the entire central portion thereof towards the respective outer surface areas.
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) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |