US3839059A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sprayable gypsum plaster composition
Assignee: WR Grace and Co Conn
•
Filing: 1973-01-09
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Granted: 1974-10-01
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Expires: 1993-01-09
Abstract
Abstract Fire-retardant coatings for structural metal members are obtained by spraying onto the metal settable plaster compositions which are air-containing pumpable aqueous slurries of compositions consisting essentially of, on a dry weight basis, from 52 to 62 percent calcined gypsum, from 2.5 to 18 percent high wet bulking cellulosic fiber, sufficient foaming agent to achieve good workability and satisfactory pumping characteristics, and enough lightweight aggregate to complete the formula.
Inventors
- 👤 R Rothfelder
- 👤 R Bragg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 01:31
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/14; C04B18/00; C04B18/04; C04B18/18; C04B18/24; C04B18/241; C04B20/00; C04B20/0048; C04B20/0052; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/91
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
92 words
A GYPSUM PLASTER COMPOSITION, CAPABLE OF YIELDING A SETTABLE, SPRAYING SLURRY ON ADDITION OF WATER, WHICH CONSISTS ESSENTIALLY OF A DRY WEIGHT BASIS, CALCINED GYPSUM, ABOUT 52 TO 62 PERCENT, HIGH WET BULKING CELLULOSIC FIBER, ABOUT 2.5 TO ABOUT 18 PERCENT, AN AIR-ENTRAINING AGENT, ABOUT 0.2 PERCENT, AND SUFFICIENT LIGHTWEIGHT AGGREGATE TO COMPLETE THE FORMULA, SAID CELLULOSIC FIBER HAVING SUFFICIENT WET BULKING CAPACITY THAT WHEN INCORPORATED IN THE SAID COMPOSITION, ADMIXED WITH WATER, PUMPED AND SPRAYED, YIELDS AT LEAST ABOUT 24 BOARD FEET OF PRODUCT PER 50 POUNDS OF THE DRY COMPOSITION.
Claim 2
Dependent Claim
92 words
A GYPSUM PLASTER COMPOSITION, CAPABLE OF YIELDING A SETTABLE, SPRAYING SLURRY ON ADDITION OF WATER, WHICH CONSISTS ESSENTIALLY OF A DRY WEIGHT BASIS, CALCINED GYPSUM, ABOUT 52 TO 62 PERCENT, HIGH WET BULKING CELLULOSIC FIBER, ABOUT 2.5 TO ABOUT 18 PERCENT, AN AIR-ENTRAINING AGENT, ABOUT 0.2 PERCENT, AND SUFFICIENT LIGHTWEIGHT AGGREGATE TO COMPLETE THE FORMULA, SAID CELLULOSIC FIBER HAVING SUFFICIENT WET BULKING CAPACITY THAT WHEN INCORPORATED IN THE SAID COMPOSITION, ADMIXED WITH WATER, PUMPED AND SPRAYED, YIELDS AT LEAST ABOUT 24 BOARD FEET OF PRODUCT PER 50 POUNDS OF THE DRY COMPOSITION.
Claim 3
Dependent Claim
21 words
The composition of claim 1 wherein the cellulosic fiber constitutes from about 3 to about 8 percent of the dry composition.
Claim 4
Dependent Claim
15 words
The composition of claim 2 wherein the cellulosic fiber is provided by a sulfite pulp.
Claim 5
Dependent Claim
15 words
The composition of claim 2 wherein the cellulosic fiber is provided by a kraft pulp.
Claim 6
Dependent Claim
27 words
The composition of claim 1 wherein the lightweight aggregate is an expanded vermiculite having a bulk density within the range of about 4.5 to about 8 pcf.
Claim 7
Dependent Claim
28 words
The composition of claim 1 wherein the wet bulking capacity of said cellulosic fiber is sufficient to yield at least about 28 to 32 board feet of product.
Claim 8
Dependent Claim
32 words
A sprayable, settable plaster slurry consisting of the plaster composition of claim 1 suspended in water at a level of about 9 to about 14 gallons per 50 pounds of dry composition.
Claim 9
Dependent Claim
21 words
A fire-retardant set gypsum plaster composition metal structural assembly consisting of structural metal members coated with the composition of claim 6.
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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) | 1977-09-30 | 1978-04-01 | 1978-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-30 | 1982-04-01 | 1982-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-30 | 1986-04-01 | 1986-10-01 | $7700.00 | Window Closed / Lapsed |