US3211665A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical brightener composition for paper
Assignee: Wyeth Holdings LLC
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Filing: 1962-12-03
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Granted: 1965-10-12
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Expires: 1982-12-03
Abstract
No abstract record available.
Inventors
- 👤 Allen William
- 👤 Gerard Robert Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:04
CPC Classifications
D; D21; D21H; D21H21/00; D21H21/14; D21H21/30
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
39 words
IN THE PROCESS OF NEUTRALIZING THE YELLOWISH TINGE OF NATURAL CELLULOSE FIBERS BY CONTACTING SAID FIBERS WITH A BRIGHTENER COMPOSITION, THE IMPROVEMENT WHICH COMPRISES USING AS SAID BRIGHTENER COMPOSITION, AN AQUEOUS MIXTURE OF (A) A BRIGHTENER OF THE FORMULA:
Claim 2
Dependent Claim
39 words
IN THE PROCESS OF NEUTRALIZING THE YELLOWISH TINGE OF NATURAL CELLULOSE FIBERS BY CONTACTING SAID FIBERS WITH A BRIGHTENER COMPOSITION, THE IMPROVEMENT WHICH COMPRISES USING AS SAID BRIGHTENER COMPOSITION, AN AQUEOUS MIXTURE OF (A) A BRIGHTENER OF THE FORMULA:
Claim 3
Dependent Claim
23 words
A COMPOSITION SUITABLE FOR NEUTRALIZING THE YELLOWNESS IN NATURAL CELLULOSE CONSISTING ESSENTIALLY OF AN AQUEOUS MIXTURE OF (A) A BRIGHTENER OF THE FORMULA:
Claim 4
Dependent Claim
23 words
A COMPOSITION SUITABLE FOR NEUTRALIZING THE YELLOWNESS IN NATURAL CELLULOSE CONSISTING ESSENTIALLY OF AN AQUEOUS MIXTURE OF (A) A BRIGHTENER OF THE FORMULA:
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) | 1968-10-11 | 1969-04-12 | 1969-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-10-11 | 1973-04-12 | 1973-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-10-11 | 1977-04-12 | 1977-10-12 | $7700.00 | Window Closed / Lapsed |