US3966618A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Clarification of xanthan gum
Assignee: Merck and Co Inc
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Filing: 1974-10-10
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Granted: 1976-06-29
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Expires: 1994-10-10
Abstract
Abstract Fermentation broths and other aqueous suspensions containing a dissolved xanthan gum and suspended solids resulting from the fermentation producing the xanthan gum are clarified by treatment with a minor amount of a protease enzyme. The injectivity of aqueous solutions containing xanthan gum so clarified is improved, in oil well flooding operations, over solutions not so treated.
Inventors
- 👤 George T. Colegrove
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:50
CPC Classifications
C; C08; C08B; C08B37/00; C08B37/0006; C08B37/0024; C08B37/0033; C12; C12P; C12P19/00; C12P19/04; C12P19/06; Y; Y10; Y10S; Y10S435/00; Y10S435/8215; Y10S435/822; Y10S435/91; Y10S507/00; Y10S507/935; Y10S507/936
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
27 words
A solid composition comprising from about 85-95% by weight of solid xanthan gum containing cellular fermentation solids and about 5-15% by weight of an alkaline protease enzyme.
Claim 2
Dependent Claim
27 words
A solid composition comprising from about 85-95% by weight of solid xanthan gum containing cellular fermentation solids and about 5-15% by weight of an alkaline protease enzyme.
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) | 1979-06-29 | 1979-12-29 | 1980-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-29 | 1983-12-29 | 1984-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-29 | 1987-12-29 | 1988-06-29 | $7700.00 | Window Closed / Lapsed |