Patent US3220899A successfully refreshed from Google Patents.
US3220899A
Expired / Lapsed
US
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Process for chemically graining lithographic plates
Assignee: Litho Chemical and Supply Co Inc
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Filing: 1962-12-20
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Granted: 1965-11-30
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Expires: 1982-12-20
Abstract
No abstract record available.
Inventors
- 👤 Robert F Leonard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:48
CPC Classifications
B; B41; B41N; B41N3/00; B41N3/03; B41N3/038
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
80 words
A PROCESS FOR CHEMICALLY GRAINING AN ALUMINUM LITHOGRAPHIC PLATE ON BOTH SIDES TO PRODUCE A SUPERIOR GRAIN STRUCTURE OF UNIFORM AND STREAKLESS CHARACTERISTICS WHICH COMPRISES IMMERSING THE SURFACE OF SUCH PLATE IN AN ALKALINE ETCHANT TO PRODUCE A PITED SURFACE, THEN IN AN ACID ETCHANT TO DEEPEN THE PITS AND FORM HILLS AND VALLEYS WITH SHARP PEAKS, AND THEN AGAIN IN AN ALKALINE ETCHANT TO REMOVE THE FINE FRAGILE PEAKS AND TO DISSOLVE WATER-INSOLUBLE FILM LEFT BY THE ACID ETCHANT.
Claim 2
Dependent Claim
80 words
A PROCESS FOR CHEMICALLY GRAINING AN ALUMINUM LITHOGRAPHIC PLATE ON BOTH SIDES TO PRODUCE A SUPERIOR GRAIN STRUCTURE OF UNIFORM AND STREAKLESS CHARACTERISTICS WHICH COMPRISES IMMERSING THE SURFACE OF SUCH PLATE IN AN ALKALINE ETCHANT TO PRODUCE A PITED SURFACE, THEN IN AN ACID ETCHANT TO DEEPEN THE PITS AND FORM HILLS AND VALLEYS WITH SHARP PEAKS, AND THEN AGAIN IN AN ALKALINE ETCHANT TO REMOVE THE FINE FRAGILE PEAKS AND TO DISSOLVE WATER-INSOLUBLE FILM LEFT BY THE ACID ETCHANT.
References Cited (Backward Citations)
US2180798A
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US2396685A
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US2507314A
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US2650157A
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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 |