US3221079A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dihydroxy diphenyl sulfone/formaldehyde condensates as curing agents for polyvinyl alcohol
Assignee: Armstrong World Industries Inc
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Filing: 1961-04-12
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Granted: 1965-11-30
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Expires: 1981-04-12
Abstract
No abstract record available.
Inventors
- 👤 Thomas G Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:55
CPC Classifications
C; C08; C08L; C08L29/00; C08L29/02; C08L29/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
29 words
A CURABLE COMPOSITION COMPRISING POLYVINYL ALCOHOL AND FROM 2-30% BY WEIGHT OF THE CONDENSATION PRODUCT UNDER ALKALINE CONDITIONS OF 4 MOLS OF FORMALDEHYDE PER MOL OF DIHYDROXY DIPHENYL SULFONE.
Claim 2
Dependent Claim
29 words
A CURABLE COMPOSITION COMPRISING POLYVINYL ALCOHOL AND FROM 2-30% BY WEIGHT OF THE CONDENSATION PRODUCT UNDER ALKALINE CONDITIONS OF 4 MOLS OF FORMALDEHYDE PER MOL OF DIHYDROXY DIPHENYL SULFONE.
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) | 1968-11-29 | 1969-05-31 | 1969-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-29 | 1973-05-31 | 1973-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-29 | 1977-05-31 | 1977-11-30 | $7700.00 | Window Closed / Lapsed |