US4992332A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Porous hollow fiber
Assignee: Ube Corp
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Filing: 1989-04-27
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Granted: 1991-02-12
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Expires: 2009-04-27
Abstract
Abstract The improvement in a porous hollow fiber having a large number of micropores in its surrounding wall, in which walls of said pores are coated with an essentially water-insoluble alkylcellulose derivative such as ethylcellulose, carboxymethylethylcellulose, hydroxypropylmethylcellulose acetate succinate or hydroxypropylmethylcellulose phthalate, or poly(2-hydroxyethyl methacrylate).
Inventors
- 👤 Eiichi Kamei
- 👤 Yasushi Shimomura
- 👤 Mitsuo Yamanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:51
CPC Classifications
B; B01; B01D; B01D67/00; B01D67/0081; B01D67/0088; B01D69/00; B01D69/08; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/2935; Y10T428/2973; Y10T428/2975; Y10T428/2978
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
45 words
In a porous hollow polypropylene fiber having a large number of micropores in its surrounding wall, the improvment in which walls of said pores are coated with an essentially water-insoluble polymer selected from the group consisting of, carboxymethylethylcellulose, hydroxypropylmethylcellulose acetate succinate and hydropropylmethylcellulose phthalate and.
Claim 2
Dependent Claim
45 words
In a porous hollow polypropylene fiber having a large number of micropores in its surrounding wall, the improvment in which walls of said pores are coated with an essentially water-insoluble polymer selected from the group consisting of, carboxymethylethylcellulose, hydroxypropylmethylcellulose acetate succinate and hydropropylmethylcellulose phthalate and.
Claim 3
Dependent Claim
24 words
The porous hollow fiber as claimed in claim 1, wherein outer and inner surfaces of the surrounding wall are further coated with said polymer.
Claim 4
Dependent Claim
31 words
The porous hollow fiber as claimed in claim 1, wherein at least one of outer and inner surfaces of the surrounding wall is coated with a non-porous layer of said polymer.
Claim 5
Dependent Claim
22 words
The porous hollow fiber as claimed in claim 1, wherein said micropores in the surrounding wall are filled up with said polymer.
Claim 6
Dependent Claim
40 words
The porous hollow fiber as claimed in claim 1, wherein said polymer is hydroxypropylmethylcellulose acetate succinate having substituents comprising 12-28 mol.% of methoxyl group, 4-23 mol.% of hydroxypropoxyl group, 2-16 mol.% of acetyl group and 4-28 mol.% of succinoyl group.
Claim 7
Dependent Claim
26 words
The porous hollow fiber as claimed in claim 1, wherein said polymer is carboxymethylethylcellulose containing 8.9-14.9 wt.% of carboxymethyl group and 32.5-43.0 wt.% of ethoxyl group.
Claim 8
Dependent Claim
34 words
The porous hollow fiber as claimed in claim 1, wherein said polymer is hydroxypropylmethylcelulose phthalate having substituents comprising 18-24 mol.% of methoxyl group, 5-10 mol.% of hydroxypropoxyl group, and 21-35 mol.% of carboxybenzoyl group.
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) | 1994-02-11 | 1994-08-13 | 1995-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-11 | 1998-08-13 | 1999-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-11 | 2002-08-13 | 2003-02-12 | $7700.00 | Window Closed / Lapsed |