US3238020A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acid-base test materials
Assignee: EIDP Inc
•
Filing: 1961-07-26
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Granted: 1966-03-01
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Expires: 1981-07-26
Abstract
No abstract record available.
Inventors
- 👤 Jr Bernhardt Joseph Eiseman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:59
CPC Classifications
G; G01; G01N; G01N31/00; G01N31/22; G01N31/221; Y; Y10; Y10T; Y10T436/00; Y10T436/15
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
54 words
AN ACID INDICATOR CONSISTING OF A PROUS CELLULOSIC MATERIAL SUBSTRATE CONTAINING AN ORGANIC DYE WHICH IS CAPABLE OF UNDERGOING A COLOR CHANGE OF A PH OS LESS THAN 7.0 AND FROM ABOUT 5% TO ABOUT 50% BY WEIGHT OF A NEUTRAL, WATER SOLUBLE, SATURATED ALIPHATIC POLYHYDROXY COMPOUND COMPOSED ENTIRELY OF CARBON, HYDROGEN AND OXYGEN.
Claim 2
Dependent Claim
54 words
AN ACID INDICATOR CONSISTING OF A PROUS CELLULOSIC MATERIAL SUBSTRATE CONTAINING AN ORGANIC DYE WHICH IS CAPABLE OF UNDERGOING A COLOR CHANGE OF A PH OS LESS THAN 7.0 AND FROM ABOUT 5% TO ABOUT 50% BY WEIGHT OF A NEUTRAL, WATER SOLUBLE, SATURATED ALIPHATIC POLYHYDROXY COMPOUND COMPOSED ENTIRELY OF CARBON, HYDROGEN AND OXYGEN.
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) | 1969-02-28 | 1969-08-30 | 1970-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-02-28 | 1973-08-30 | 1974-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-02-28 | 1977-08-30 | 1978-03-01 | $7700.00 | Window Closed / Lapsed |