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US3220899A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for chemically graining lithographic plates

Assignee: Litho Chemical and Supply Co Inc
•
Filing: 1962-12-20
•
Granted: 1965-11-30
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Expires: 1982-12-20
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Abstract

No abstract record available.

Inventors

  • 👤 Robert F Leonard

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 10:13
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 Cited
US2396685A Cited
US2507314A Cited
US2650157A Cited
US2699382A Cited
US3010854A Cited
US2942955A Cited
US3085917A Cited

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

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