US4374710A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrolytic graining of aluminum with nitric and oxalic acids
Assignee: CNA Holdings LLC
•
Filing: 1982-03-18
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Granted: 1983-02-22
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Expires: 2002-03-18
Abstract
Abstract Aluminum is electrolytically grained in an aqueous solution of nitric and oxalic acids to provide a surface structure suitable for use as part of a lithographic printing plate. The electrolyte may also optionally contain boric acid and/or aluminum nitrate and/or hydrogen peroxide.
Inventors
- 👤 John E. Walls
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:36
CPC Classifications
C; C25; C25F; C25F3/00; C25F3/02; C25F3/04; B; B41; B41N; B41N3/00; B41N3/03; B41N3/034
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
55 words
A method of treating the surface of a sheet of aluminum or the alloys thereof which comprises electrolytically graining said sheet under electrolyzing conditions in an aqueous solution of nitric acid and oxalic acid in a sufficient concentration and for a sufficient length of time to provide a finely grained surface topography to said sheet.
Claim 2
Independent Claim
55 words
A method of treating the surface of a sheet of aluminum or the alloys thereof which comprises electrolytically graining said sheet under electrolyzing conditions in an aqueous solution of nitric acid and oxalic acid in a sufficient concentration and for a sufficient length of time to provide a finely grained surface topography to said sheet.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein the concentration of nitric acid ranges from about 3 grams/liter to about 20 grams/liter.
Claim 4
Dependent Claim
20 words
The method of claim 1 wherein the concentration of oxalic acid ranges from about 1 gram/liter to about 80 grams/liter.
Claim 5
Dependent Claim
13 words
The method of claim 1 wherein said aqueous solution further comprises boric acid.
Claim 6
Dependent Claim
13 words
The method of claim 4 wherein said aqueous solution further comprises aluminum nitrate.
Claim 7
Dependent Claim
13 words
The method of claim 1 wherein said aqueous solution further comprises aluminum nitrate.
Claim 8
Dependent Claim
13 words
The method of claim 1 wherein said aqueous solution further comprises hydrogen peroxide.
Claim 9
Dependent Claim
24 words
The method of claim 1 wherein the current density employed in said electrolytic graining ranges from about 30 to about 120 A/dm 2 .
Claim 10
Dependent Claim
13 words
The method of claim 1 wherein said electrolytically grained sheet is subsequently anodized.
Claim 11
Dependent Claim
17 words
The aluminum sheet prepared according to claim 1, 2, 3, 4, 5, 6, 7, 8 or 9.
Claim 12
Dependent Claim
22 words
The aluminum sheet prepared according to claim 1 or 9 which has a hydrophilizing composition coated on at least one surface thereof.
Claim 13
Dependent Claim
33 words
A lithographic printing plate which comprises the aluminum sheet prepared according to the method of claim 1 or 9 and a lithographic photosensitive composition coated on at least one surface of said sheet.
Claim 14
Dependent Claim
20 words
A lithographic printing plate comprising the sheet of claim 11 and a lithographic photosensitive composition coated on said hydrophilizing composition.
References Cited (Backward Citations)
SU305203A1
Cited
US4301229A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-21 | 1986-08-23 | 1987-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-21 | 1990-08-23 | 1991-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-21 | 1994-08-23 | 1995-02-22 | $7700.00 | Window Closed / Lapsed |