US3909346A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making asbestos backing sheets for vinyl floor covering
Assignee: Congoleum Corp
•
Filing: 1974-09-26
•
Granted: 1975-09-30
•
Expires: 1994-09-26
Abstract
Abstract A process for manufacturing a felt backing sheet of crysotile asbestos fibers, the sheet being saturated with a synthetic rubber latex binder, the sheet being particularly useful for backing sheets utilized in the manufacture of vinyl floor covering and the like. The process comprises a continuous precipitation of the synthetic rubber latex onto asbestos fibers without the necessity of using a coagulating aid, a precipitating agent, or other chemical or physico-chemical means for controlling the deposition of the latex. The process is carried out by admitting an aqueous asbestos slurry into a feed line and subsequently adding a latex binder thereto. The asbestos slurrylatex binder mixture is carried to an in-line blender where intimate mixture is achieved to effect precipitation of the latex onto the asbestos fibers preparatory to the formation of the backing sheet.
Inventors
- 👤 Donald C Winters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:50
CPC Classifications
D; D21; D21H; D21H13/00; D21H13/36; D21H13/38; D21H13/42; D21H17/00; D21H17/20; D21H17/33; D21H17/34; D21H17/35
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
209 words
A PROCESS FOR CONTINUOUSLY PRODUCING A SHEET OF CHRYSOTILE ASBESTOS FIBRES HAVING A LATEX BINDER, THE PROCESS BEING CARRIED OUT WITHOUT CHEMICAL ADDATIVES OR PRECIPITATING AGENTS FOR CONTROLLING THE LATEX DESPOSITION, THE PROCESS COMPRISING: A. ADMITTING AN AQUEOUS SLURRY OF ABOUT 3-6 PERCENT CONSISTENCY OF CHRYSOTILE ASBESTOS FIBRES IN WATER TO A PROCESS LINE, B. ADMITTING AT LEAST ABOUT 10 PERCENT ON A DRY WEIGHT BASIS OF A SYNTHETIC RUBBER LATEX BINDER OF ABOUT 20-30 PERCENT SOLIDS CONTENT AND FREE OF PRECUPATION CONTROLLING AGENTS TO SAID PROCESS LINE SO THAT THE RATIO OF THE RATES OF ADDITION OF THE ASBESTOS FIBER SLURRY TO THE LATEX BINDER IS SUBSTANTIALLY WITIN THE RANGE OF ABOUT 20:1 TO 30:1, C. INTRODUCING THE AQUEOUS ASBESTOS FIBERSYNTHETIC RUBBER LATEX MIXTURE INTO A BLENDER SO THAT THE RATIO OF THE VOLUME IN GALLONS OF THE MIXTURE TO THE SPEED OF THE BLENDER IN REVOLUTIONS PER MINUTE IS BETWEEN 1:3 AND 1:4 SO THAT THE SHEAR FORCES OF THE IMPELLER OF THE BLENDER THROW OUT THE LATEX PARTICLES AND THEREBY DEPOSIT THE LATEX ON THE FIBER IN A CONTROLLED MANNER WITHOUT CHEMICAL DESPOSITION CONTROLLING AGENTS, D. THEREAFTER FEEDING THE FIBROUS SLURRYBINDER MIXTURE TO A SHEET FORMING APPARATUS, AND E. FORMING A SHEET FROM SAID SLURRY MIXTURE.
Claim 2
Dependent Claim
209 words
A PROCESS FOR CONTINUOUSLY PRODUCING A SHEET OF CHRYSOTILE ASBESTOS FIBRES HAVING A LATEX BINDER, THE PROCESS BEING CARRIED OUT WITHOUT CHEMICAL ADDATIVES OR PRECIPITATING AGENTS FOR CONTROLLING THE LATEX DESPOSITION, THE PROCESS COMPRISING: A. ADMITTING AN AQUEOUS SLURRY OF ABOUT 3-6 PERCENT CONSISTENCY OF CHRYSOTILE ASBESTOS FIBRES IN WATER TO A PROCESS LINE, B. ADMITTING AT LEAST ABOUT 10 PERCENT ON A DRY WEIGHT BASIS OF A SYNTHETIC RUBBER LATEX BINDER OF ABOUT 20-30 PERCENT SOLIDS CONTENT AND FREE OF PRECUPATION CONTROLLING AGENTS TO SAID PROCESS LINE SO THAT THE RATIO OF THE RATES OF ADDITION OF THE ASBESTOS FIBER SLURRY TO THE LATEX BINDER IS SUBSTANTIALLY WITIN THE RANGE OF ABOUT 20:1 TO 30:1, C. INTRODUCING THE AQUEOUS ASBESTOS FIBERSYNTHETIC RUBBER LATEX MIXTURE INTO A BLENDER SO THAT THE RATIO OF THE VOLUME IN GALLONS OF THE MIXTURE TO THE SPEED OF THE BLENDER IN REVOLUTIONS PER MINUTE IS BETWEEN 1:3 AND 1:4 SO THAT THE SHEAR FORCES OF THE IMPELLER OF THE BLENDER THROW OUT THE LATEX PARTICLES AND THEREBY DEPOSIT THE LATEX ON THE FIBER IN A CONTROLLED MANNER WITHOUT CHEMICAL DESPOSITION CONTROLLING AGENTS, D. THEREAFTER FEEDING THE FIBROUS SLURRYBINDER MIXTURE TO A SHEET FORMING APPARATUS, AND E. FORMING A SHEET FROM SAID SLURRY MIXTURE.
Claim 3
Dependent Claim
22 words
A process as in claim 1 and wherein: said asbestos fiber slurry is about 4-5 percent asbestos fibers in water by weight.
Claim 4
Dependent Claim
32 words
A process as in claim 1 and wherein: the ratio of the feed rate of the asbestos fiber slurry to the feed rate of the latex binder is about 27:1 tO 28:1.
Claim 5
Dependent Claim
27 words
A process as in claim 1 and including: maintaining said asbestos fiber slurry at a temperature of about 80*-120*F prior to the introduction of the latex binder.
Claim 6
Dependent Claim
27 words
A process as in claim 1 and including: depositing about 10 to about 35 percent of latex binder on the asbestos fibers on a dry weight basis.
Claim 7
Dependent Claim
15 words
A process as in claim 1 and wherein: said latex binder is a styrene-butadiene latex.
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) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |