US4370168A
Expired / Lapsed
US
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Mesophase dope containing cellulose derivative and inorganic acid
Assignee: Asahi Kasei Corp
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Filing: 1980-09-19
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Granted: 1983-01-25
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Expires: 2000-09-19
Abstract
Abstract A mesophase dope useful for producing shaped articles, for example, filaments and films, comprises at least 10% by weight of at least one cellulose derivative and the balance consisting of an aqueous solution of at least 5% by weight of at least one inorganic acid, the dope exhibiting the mesophase property even in the case where no fluid dynamic stress is applied thereto.
Inventors
- 👤 Kenji Kamide
- 👤 Kunihiko Okajima
- 👤 Toshihiko Matsui
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:29
CPC Classifications
D; D01; D01F; D01F2/00; D01F2/24; D01F2/28; C; C08; C08K; C08K3/00; C08K3/01; C09; C09K; C09K19/00; C09K19/52; C09K19/54
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
50 words
A mesophase dope comprising at least 15% by weight of at least one cellulose ether, dissolved in an aqueous solution of at least 5% by weight of at least one inorganic acid, said dope exhibiting a mesophase property even in the case where no fluid dynamic stress is applied thereto.
Claim 2
Dependent Claim
50 words
A mesophase dope comprising at least 15% by weight of at least one cellulose ether, dissolved in an aqueous solution of at least 5% by weight of at least one inorganic acid, said dope exhibiting a mesophase property even in the case where no fluid dynamic stress is applied thereto.
Claim 3
Dependent Claim
43 words
A mesophase dope as claimed in claim 1 wherein said cellulose ether is selected from the group consisting of methylcellulose, ethylcellulose, cyanoethylcellulose, carboxyethylcellulose, carbamoylethylcellulose, cyanoethylcarbamoylethylcellulose, cyanoethylcarboxyethylcellulose, hydroxyethylcellulose, ethylhydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, carboxymethylcellulose, acetoxymethylcellulose, acetoxymethylcellulose acetate and possible salts of the above-mentioned cellulose ether compounds.
Claim 4
Dependent Claim
30 words
A mesophase dope as claimed in claim 1, wherein said cellulose ether is selected from the group consisting of methylcellulose, ethylcellulose, cyanoethylcellulose, carboxyethylcellulose, hydroxyethylcellulose, cyanoethylcarboxyethylcellulose, and sodium salt of carboxymethylcellulose.
Claim 5
Dependent Claim
33 words
A mesophase dope as claimed in claim 1, wherein said cellulose ether is selected from the group consisting of methylcellulose and ethylcellulose, each having a degree of substitution (DS) of 2.3 or less.
Claim 6
Dependent Claim
24 words
A mesophase dope as claimed in claim 1, wherein said cellulose ether is acetoxymethylcellulose having a degree of substitution (DS) satisfying the relation: O<DS<2.7.
Claim 7
Dependent Claim
34 words
A mesophase dope as claimed in claim 1, wherein said cellulose ether is selected from the group consisting of cyanoethylcellulose, carboxyethylcellulose, hydroxypropylcellulose, hydroxyethylcellulose each having a degree of substitution (DS) satisfying the relation: O<DS≦3.0.
Claim 8
Dependent Claim
60 words
A mesophase dope as claimed in claim 1, wherein said inorganic acid is selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, metaphosphoric acid, pyrophosphoric acid, hypophosphoric acid, sulfurous acid, fluorosulfuric acid, chlorosulfuric acid, chloric acid, hypochlorous acid, chlorous acid, perchloric acid, bromic acid, perbromic acid, hypobromous acid, hydrofluoric acid, thiocyanic acid and thiosulfuric acid.
Claim 9
Dependent Claim
42 words
A mesophase dope as claimed in claim 1, wherein said inorganic acid is selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, perchloric acid, pyrophosphoric acid, chlorosulfuric acid, thiosulfuric acid, metaphosphoric acid, thiocyanic acid and bromic acid.
Claim 10
Dependent Claim
17 words
A mesophase dope as claimed in claim 1, wherein an aqueous solution of nitric acid contains cyanoethylcellulose.
Claim 11
Dependent Claim
20 words
A mesophase dope as claimed in claim 1, wherein an aqueous solution of nitric acid or sulfuric acid contains methylcellulose.
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) | 1986-01-24 | 1986-07-26 | 1987-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-24 | 1990-07-26 | 1991-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-24 | 1994-07-26 | 1995-01-25 | $7700.00 | Window Closed / Lapsed |