US4065426A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the preparation of powdered rubber
Assignee: Mitsubishi Chemical Corp
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Filing: 1976-05-28
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Granted: 1977-12-27
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Expires: 1996-05-28
Abstract
Abstract Rubber crumbs are imparted with non-tackiness or antiblocking property by treating the crumbs with a mixture of a rubber latex and an aqueous carbon black slurry in the presence of a coagulant.
Inventors
- 👤 Takeshi Yamawaki
- 👤 Takanori Uchida
- 👤 Makoto Nakajima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:01
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; C08J3/16; C08C; C08C1/00; C08C1/14; C08J3/20; C08J3/205; C08J3/21; C08J3/215; C08J2321/00; Y; Y10; Y10S; Y10S528/00; Y10S528/931; Y10S528/934; Y10S528/936
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
118 words
A method for preparing powdered rubber comprising the steps of: (a) adding a coagulant to a rubber latex to obtain crumbs of the rubber (b) mixing said crumbs with a rubber latex and an aqueous carbon black slurry in an amount of 100 - 1000 parts by weight of carbon black per 100 parts by weight of the rubber component in the second-mentioned rubber latex; said weight of rubber component in the second conventional rubber latex being 0.5 - 50 wt. % of the rubber component of said crumbs from set (a), (c) treating the resulting mixture in the presence of a coagulant; and (d) separating the thus treated crumbs from the serum and drying the separated crumbs.
Claim 2
Independent Claim
118 words
A method for preparing powdered rubber comprising the steps of: (a) adding a coagulant to a rubber latex to obtain crumbs of the rubber (b) mixing said crumbs with a rubber latex and an aqueous carbon black slurry in an amount of 100 - 1000 parts by weight of carbon black per 100 parts by weight of the rubber component in the second-mentioned rubber latex; said weight of rubber component in the second conventional rubber latex being 0.5 - 50 wt. % of the rubber component of said crumbs from set (a), (c) treating the resulting mixture in the presence of a coagulant; and (d) separating the thus treated crumbs from the serum and drying the separated crumbs.
Claim 3
Dependent Claim
26 words
A method according to claim 1, wherein the coagulation of the first-mentioned rubber latex in the step (a) is effected in the presence of carbon black.
Claim 4
Dependent Claim
31 words
A method according to claim 2, wherein said carbon black is present in an amount of 30 - 200 parts by weight per 100 parts by weight of the rubber component.
Claim 5
Dependent Claim
19 words
A method according to claim 2, wherein said carbon black is used in the state of an aqueous slurry.
Claim 6
Dependent Claim
26 words
A method according to claim 1, wherein the coagulation of the first-mentioned rubber latex in the step (a) is effected in the presence of an oil.
Claim 7
Dependent Claim
30 words
A method according to claim 5, wherein said oil is present in an amount of 1 - 80 parts by weight per 100 parts by weight of the rubber component.
Claim 8
Dependent Claim
17 words
A method according to claim 5, wherein said oil is used in the state of an emulsion.
Claim 9
Dependent Claim
25 words
A method according to claim 1, wherein said crumbs obtained in the step (a) are neutralized with an alkaline substance prior to the step (b).
Claim 10
Dependent Claim
44 words
A method according to claim 1, wherein the amount of the carbon black used in the step (b) is in the range of 10 - 100 % by weight of the total amount of the carbon black contained in the final powdered rubber product.
Claim 11
Dependent Claim
16 words
A method according to claim 1, wherein said coagulant in the step (a) is an acid.
Claim 12
Dependent Claim
25 words
A method according to claim 1, wherein the crumb slurry obtained in the step (a) has a pH in the range of 1 - 6.
Claim 13
Dependent Claim
30 words
A method according to claim 1, wherein both of said rubber latices are selected from the group consisting of styrene-butadiene copolymer rubber, natural rubber, polybutadiene rubber and nitrile-butadiene copolymer rubber.
Claim 14
Dependent Claim
16 words
A method according to claim 1, wherein said coagulant in the step (c) is an acid.
References Cited (Backward Citations)
US3654218A
Cited
US3767605A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-12-26 | 1981-06-27 | 1981-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-26 | 1985-06-27 | 1985-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-26 | 1989-06-27 | 1989-12-27 | $7700.00 | Window Closed / Lapsed |