US3870537A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shaped solid body of pullulan ether and methods of making and using the same
Assignee: Hayashibara Seibutsu Kagaku Kenkyujo KK
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Filing: 1974-02-25
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Granted: 1975-03-11
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Expires: 1994-02-25
Abstract
Abstract Pullulan reacts with alkylating agents such as dimethyl sulfate, diethyl sulfate, ethylene oxide, and propylene oxide to form the corresponding lower-alkyl or hydroxy-lower-alkyl ethers which are much less soluble in water than pullulan, but retain sufficient sensitivity to moisture to be biodegradable when they do not contain more than one, and preferably not more than 0.5, alkoxy or hydroxyalkoxy group per glucose unit in the pullulan molecule. Films and fibers of the ethers are mechanically strong and are readily plasticised with water-soluble polyhydric alcohols. The ethers can be molded above their softening temperature in conventional injection or compression molding equipment. The films are practically impervious to atmospheric oxygen and suitable as packaging material.
Inventors
- 👤 Hiromi Hijiya
- 👤 Makoto Shiosaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:28
CPC Classifications
D; D01; D01F; D01F9/00; C; C08; C08B; C08B37/00; C08B37/0006; C08B37/0009; C08B37/0018
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
49 words
A SHAPED, SOLID BODY ESSENTIALLY CONSISTING OF A LOWERALKYL OR HYDROXY-LOWER-ALKYL ETHER OF PULLULAN AND 0% TO 5% OF A POLYHYDRIC ALCOHOL AT LEAST AS SOLUBLE IN WATER AS SORBITOL, SAID LOWER-ALKYL HAVING ONE TO FOUR CARBON ATOMS, AND SAID PULLUAN HAVING A MOLECULAR WEIGHT OF 10,000 TO 5,000,000.
Claim 2
Dependent Claim
49 words
A SHAPED, SOLID BODY ESSENTIALLY CONSISTING OF A LOWERALKYL OR HYDROXY-LOWER-ALKYL ETHER OF PULLULAN AND 0% TO 5% OF A POLYHYDRIC ALCOHOL AT LEAST AS SOLUBLE IN WATER AS SORBITOL, SAID LOWER-ALKYL HAVING ONE TO FOUR CARBON ATOMS, AND SAID PULLUAN HAVING A MOLECULAR WEIGHT OF 10,000 TO 5,000,000.
Claim 3
Dependent Claim
49 words
A shaped, solid body essentially consisting of a lower-alkyl or hydroxy-lower-alkyl ether of pullulan and 0% to 5% of a polyhydric alcohol at least as soluble in water as sorbitol, said lower-alkyl having one to four carbon atoms, and said pullulan having a molecular weight of 10,000 to 5,000,000.
Claim 4
Dependent Claim
49 words
A shaped, solid body essentially consisting of a lower-alkyl or hydroxy-lower-alkyl ether of pullulan and 0% to 5% of a polyhydric alcohol at least as soluble in water as sorbitol, said lower-alkyl having one to four carbon atoms, and said pullulan having a molecular weight of 10,000 to 5,000,000.
Claim 5
Dependent Claim
36 words
A body as set forth in claim 1, wherein alkyl and hydroxyalkyl has up to 3 carbon atoms, said ether containing up to 0.5 alkoxy or hydroxyalkoxy group per glucose unit in the molecule of pullulan.
Claim 6
Dependent Claim
18 words
A body as set forth in claim 2, wherein said polyhydric alcohol is glycerol, ethyleneglycol, sorbitol, or maltitol.
Claim 7
Dependent Claim
23 words
A body as set forth in claim 3 essentially consisting of said hydroxy-lower-alkyl ether and said 0% to 5% of said polyhydric alcohol.
Claim 8
Dependent Claim
68 words
A method of making a body as set forth in claim 1 which comprises shaping a material essentially consisting of said lower-alkyl or hydroxy-lower-alkyl ether of pullulan containing not more than one alkoxy or hydroxyalkoxy group per glucose unit in the pullulan molecule and of 0% to 5% of a polyhydric alcohol soluble in water under pressure and at a temperature above the softening temperature of said material.
Claim 9
Dependent Claim
27 words
A method as set forth in claim 5, wherein said material essentially consists of said hydroxy-lower-alkyl ether and of said 0% to 5% of said polyhydric alcohol.
Claim 10
Dependent Claim
77 words
A method of making a body as set forth in claim 1 which comprises a. preparing an aqueous solution of said lower-alkyl or hydroxy-lower-alkyl ether of pullulan containing not more than one alkoxy or hydroxyalkoxy group per glucose unit in the pullulan molecule and of 0% to 5% of a polyhydric alcohol soluble in water; b. imparting a shape to the prEpared solution; and c. removing enough water from the shaped solution to make the residue shape-retaining.
Claim 11
Dependent Claim
28 words
A method as set forth in claim 7, wherein said aqueous solution essentially consists of water, said hydroxy-lower-alkyl ether, and said 0% to 5% of a polyhydric alcohol.
Claim 12
Dependent Claim
27 words
A method of protecting an object from oxidation by atmospheric oxygen which comprises sealing said object in an envelope of the body set forth in claim 1.
References Cited (Backward Citations)
US3784390A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |