Patent US3957571A successfully refreshed from Google Patents.
← Back to Patent Explorer
US3957571A Expired / Lapsed US ⏱️ 0.0 years remaining

Surface treatment of asbestos fibers

Assignee: Johns Manville Corp
•
Filing: 1974-10-10
•
Granted: 1976-05-18
•
Expires: 1994-10-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Treatment of asbestos fiber with a first coating of from about 0.1 to 5 weight percent of a phosphate, or acid thereof, and subsequent addition of a nonfoaming anionic dispersant on the coated fiber produces an asbestos fiber product that possesses improved filtration properties. This treated asbestos improves the production rate of articles from cement slurries or pastes containing asbestos.

Inventors

  • 👤 Frederick Mercer Bodycomb, Jr.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 18:19
CPC Classifications
C; C04; C04B; C04B20/00; C04B20/10

Claims Analysis

Total Claims: 33
Claim 1
Independent Claim 73 words
A process for improving the drainage characteristics of chrysotile asbestos fibers which comprises treating said fibers with an aqueous solution of a phosphate compound, or of a corresponding acid, to form on the fiber a deposit of up to 5 weight percent of the fibers, the improvement comprising subsequently adding to the treated fibers at least about 0.05 weight percent, based on the weight of the fibers, of a nonfoaming anionic sulfonated dispersant.
Claim 2
Dependent Claim 73 words
A process for improving the drainage characteristics of chrysotile asbestos fibers which comprises treating said fibers with an aqueous solution of a phosphate compound, or of a corresponding acid, to form on the fiber a deposit of up to 5 weight percent of the fibers, the improvement comprising subsequently adding to the treated fibers at least about 0.05 weight percent, based on the weight of the fibers, of a nonfoaming anionic sulfonated dispersant.
Claim 3
Dependent Claim 28 words
A process as defined in claim 1 wherein the amount of dispersant added to the fibers is in the range of about 0.1 to about 1.2 weight percent.
Claim 4
Dependent Claim 29 words
A process as defined in claim 3 wherein the amount of said dispersant added to the fibers is in the range of about 0.2 to about 0.8 weight percent.
Claim 5
Dependent Claim 24 words
A process as defined in claim 1 wherein the amount of dispersant added is in the range of about 0.2 and 0.4 weight percent.
Claim 6
Dependent Claim 29 words
A process as defined in claim 1 wherein the dispersant is added by spraying either a dry powder or an aqueous solution of the dispersant onto the treated fibers.
Claim 7
Dependent Claim 29 words
A process as defined in claim 3 wherein the dispersant is added by spraying either a dry powder or an aqueous solution of the dispersant onto the treated fibers.
Claim 8
Dependent Claim 20 words
A process as defined in claim 1 wherein the dispersant is added in bulk form to the treated asbestos fibers.
Claim 9
Dependent Claim 20 words
A process as defined in claim 3 wherein the dispersant is added in bulk form to the treated asbestos fibers.
Claim 10
Dependent Claim 20 words
A process as defined in claim 1 wherein the dispersant is a sodium salt of a condensed naphthalene sulfonic acid.
Claim 11
Dependent Claim 20 words
A process as defined in claim 3 wherein the dispersant is a sodium salt of a condensed naphthalene sulfonic acid.
Claim 12
Dependent Claim 48 words
Chrysotile asbestos fibers in a loose form containing a phosphate compound or corresponding acid, on the surfaces thereof, the improvement comprising a nonfoaming anionic sulfonated dispersant also present with the fibers in an amount of at least 0.05 weight percent, based on the weight of the asbestos fibers.
Claim 13
Dependent Claim 48 words
Chrysotile asbestos fibers in a loose form containing a phosphate compound or corresponding acid, on the surfaces thereof, the improvement comprising a nonfoaming anionic sulfonated dispersant also present with the fibers in an amount of at least 0.05 weight percent, based on the weight of the asbestos fibers.
Claim 14
Dependent Claim 27 words
Chrysotile asbestos fibers as defined in claim 11 wherein the dispersant is present in an amount in the range of about 0.1 to about 1.2 weight percent.
Claim 15
Dependent Claim 27 words
Chrysotile asbestos fibers as defined in claim 12 wherein the dispersant is present in an amount in the range of about 0.2 to about 0.8 weight percent.
Claim 16
Dependent Claim 27 words
Chrysotile asbestos fibers as defined in claim 13 wherein the dispersant is present in an amount in the range of about 0.2 to about 0.4 weight percent.
Claim 17
Dependent Claim 17 words
Chrysotile asbestos fibers as defined in claim 12 wherein the dispersant is nonuniformly distributed among the fibers.
Claim 18
Dependent Claim 17 words
Chrysotile asbestos fibers as defined in claim 13 wherein the dispersant is nonuniformly distributed among the fibers.
Claim 19
Dependent Claim 24 words
Chrysotile asbestos fibers as defined in claim 12 wherein at least a portion of the dispersant is present as a coating on the fibers.
Claim 20
Dependent Claim 24 words
Chrysotile asbestos fibers as defined in claim 13 wherein at least a portion of the dispersant is present as a coating on the fibers.
Claim 21
Dependent Claim 21 words
Chrysotile asbestos fibers as defined in claim 11 wherein the dispersant is a sodium salt of a condensed naphthalene sulfonic acid.
Claim 22
Dependent Claim 21 words
Chrysotile asbestos fibers as defined in claim 13 wherein the dispersant is a sodium salt of a condensed naphthalene sulfonic acid.
Claim 23
Dependent Claim 78 words
A process of forming a product containing chrysotile asbestos fibers, at least a portion of the fibers having been treated with a phosphate compound, or corresponding acid, wherein a slurry or paste containing said fibers is deposited on a porous surface and a fibrous product is formed by filtration, the improvement comprising adding to the aqueous slurry or paste at least about 0.05 weight percent, based on the weight of chrysotile asbestos fibers present, nonfoaming anionic sulfonated dispersant.
Claim 24
Dependent Claim 78 words
A process of forming a product containing chrysotile asbestos fibers, at least a portion of the fibers having been treated with a phosphate compound, or corresponding acid, wherein a slurry or paste containing said fibers is deposited on a porous surface and a fibrous product is formed by filtration, the improvement comprising adding to the aqueous slurry or paste at least about 0.05 weight percent, based on the weight of chrysotile asbestos fibers present, nonfoaming anionic sulfonated dispersant.
Claim 25
Dependent Claim 25 words
A process as defined in claim 21 wherein the amount of dispersant added is in the range of about 0.1 to about 0.8 weight percent.
Claim 26
Dependent Claim 25 words
A process as defined in claim 22 wherein the amount of dispersant added is in the range of about 0.2 to about 0.4 weight percent.
Claim 27
Dependent Claim 19 words
A process as defined in claim 22 wherein the dispersant is added to the slurry as a separate addition.
Claim 28
Dependent Claim 28 words
A process as defined in claim 24 wherein at least a portion of the dispersant added is in the form of a coating on the chrysotile asbestos fibers.
Claim 29
Dependent Claim 22 words
A process as defined in claim 22 wherein the dispersant is added to the slurry before the chrysotile asbestos fibers are added.
Claim 30
Dependent Claim 23 words
A process as defined in claim 22 wherein the dispersant is added to the slurry after the chrysotile asbestos fibers have been added.
Claim 31
Dependent Claim 15 words
A process as defined in claim 22 wherein the slurry also contains hydraulic cement particles.
Claim 32
Dependent Claim 20 words
A process as defined in claim 22 wherein the dispersant is a sodium salt of a condensed naphthalene sulfonic acid.
Claim 33
Dependent Claim 19 words
A process as defined in claim 23 wherein the dispersant is a salt of a condensed naphthalene sulfonic acid.

References Cited (Backward Citations)

US3630012A Cited
US3535150A Cited
US3715230A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-05-18 1979-11-17 1980-05-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-05-18 1983-11-17 1984-05-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-05-18 1987-11-17 1988-05-18 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag