Patent US3715230A successfully refreshed from Google Patents.
US3715230A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual treatment of asbestos fibers
Assignee: Johns Manville Corp
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Filing: 1971-02-12
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Granted: 1973-02-06
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Expires: 1991-02-12
Abstract
Abstract Treatment of asbestos fiber with a first coating of at least about 0.4 percent by weight of alkali-metal silicate solids or colloidal silica, and subsequent distribution of a non-foaming anionic dispersant on the coated fiber produces an asbestos fiber product that possesses improved filtration properties. The fiber product improves the production rate of articles from asbestoscement slurries or pastes and eliminates the loss in strength of asbestos-cement articles that usually results from inclusion of silicate-treated fibers in the slurries or pastes.
Inventors
- 👤 T Sadler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:46
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/24; C04B20/00; C04B20/10; C04B20/12; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/294; Y10T428/296; Y10T428/31504; Y10T428/31652; Y10T428/31656
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
65 words
An asbestos fiber product having improved filtration and good strength characteristics and capable of being packaged and stored, comprising: chrysotile asbestos fibers at least partially coated with at least about 0.4 percent by weight of material selected from the group consisting of alkali metal silicate solids, silica and mixtures thereof, and having a non-foaming anionic sulfonated dispersant distributed on the surface of the coated fibers.
Claim 2
Dependent Claim
65 words
An asbestos fiber product having improved filtration and good strength characteristics and capable of being packaged and stored, comprising: chrysotile asbestos fibers at least partially coated with at least about 0.4 percent by weight of material selected from the group consisting of alkali metal silicate solids, silica and mixtures thereof, and having a non-foaming anionic sulfonated dispersant distributed on the surface of the coated fibers.
Claim 3
Dependent Claim
48 words
The product of claim 1 including up to about 2 percent by weight, based on the weight of the fiber, of alkali metal silicate solids and from about 0.05 to about 5.0 percent by weight based on the weight of the fiber of a non-foaming anionic sulfonated dispersant.
Claim 4
Dependent Claim
18 words
The product of claim 2 in which the dispersant comprises a sodium salt of condensed naphthalene sulfonic acid.
Claim 5
Dependent Claim
98 words
A process for producing an asbestos fiber product that possesses improved filtration characteristics and improving the production rate of asbestos cement articles without decreasing the strength of such articles comprising: applying a spray comprising material selected from the group consisting of an aqueous solution of alkali metal silicate, suspended colloidal silica and mixtures thereof, to asbestos fiber while maintaining the fiber in an air suspension to deposit at least about 0.4 percent by weight of solids on the air-suspended fibers, and subsequently adding a non-foaming anionic sulfonated dispersant to the fiber to distribute said dispersant on said fibers.
Claim 6
Dependent Claim
98 words
A process for producing an asbestos fiber product that possesses improved filtration characteristics and improving the production rate of asbestos cement articles without decreasing the strength of such articles comprising: applying a spray comprising material selected from the group consisting of an aqueous solution of alkali metal silicate, suspended colloidal silica and mixtures thereof, to asbestos fiber while maintaining the fiber in an air suspension to deposit at least about 0.4 percent by weight of solids on the air-suspended fibers, and subsequently adding a non-foaming anionic sulfonated dispersant to the fiber to distribute said dispersant on said fibers.
Claim 7
Dependent Claim
21 words
The process of claim 1 in which the non-foaming anionic sulfonated dispersant is added to the fiber as a dry powder.
Claim 8
Dependent Claim
23 words
The process of claim 1 in which the non-foaming anionic sulfonated dispersant is placed in an aqueous solution and sprayed on the fiber.
Claim 9
Dependent Claim
32 words
The process of claim 1 in which the anionic sulfonated dispersant is added in amounts from about 0.05 to about 5.0 percent by weight based on the weight of the asbestos fiber.
Claim 10
Dependent Claim
20 words
The process of claim 7 in which the sulfonic acid derivative is a sodium salt of condensed naphthalene sulfonic acid.
Claim 11
Dependent Claim
25 words
The process of claim 1 in which the alkali metal silicate is selected from the group consisting of sodium and potassium silicates and mixtures thereof.
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) | 1976-02-06 | 1976-08-07 | 1977-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-06 | 1980-08-07 | 1981-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-06 | 1984-08-07 | 1985-02-06 | $7700.00 | Window Closed / Lapsed |