Patent US5419614A successfully refreshed from Google Patents.
Patent US4502925A successfully refreshed from Google Patents.
US4502925A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for aluminum surface preparation
Assignee: CNA Holdings LLC
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Filing: 1984-06-11
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Granted: 1985-03-05
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Expires: 2004-06-11
Abstract
Abstract A method for treating an aluminum sheet useful for lithography by etching said sheet in an aqueous bath containing up to about 25% of nitric and/or hydrochloric acids and from about 1% to about 25% of an inorganic fluorine containing acid or salt thereof. Said etching step is sequentially followed by electrochemical graining and anodizing process steps.
Inventors
- 👤 John E. Walls
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:52
CPC Classifications
B; B41; B41N; B41N3/00; B41N3/03; B41N3/034; C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/20; C25; C25D; C25D11/00; C25D11/02; C25D11/04; C25D11/06; C25F; C25F3/00; C25F3/02; C25F3/04
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
122 words
A method for treating an aluminum sheet which comprises: (a) immersing said sheet in an aqueous bath containing (i) up to about 25% by weight of hydrochloric and/or nitric acids, and (ii) from about 1 to about 25% by weight of an inorganic fluorine containing acid or a salt thereof; said immersion being conducted for a length of time sufficient to impart an etch to the surface of said aluminum sheet; and (b) electrochemically graining said sheet in an aqueous electrolyte comprising one or more acids selected from the group consisting of nitric acid and hydrochloric acid; and (c) anodizing said sheet in an aqueous electrolyte comprising one or more acids selected from the group consisting of sulfuric acid and phosphoric acid.
Claim 2
Independent Claim
122 words
A method for treating an aluminum sheet which comprises: (a) immersing said sheet in an aqueous bath containing (i) up to about 25% by weight of hydrochloric and/or nitric acids, and (ii) from about 1 to about 25% by weight of an inorganic fluorine containing acid or a salt thereof; said immersion being conducted for a length of time sufficient to impart an etch to the surface of said aluminum sheet; and (b) electrochemically graining said sheet in an aqueous electrolyte comprising one or more acids selected from the group consisting of nitric acid and hydrochloric acid; and (c) anodizing said sheet in an aqueous electrolyte comprising one or more acids selected from the group consisting of sulfuric acid and phosphoric acid.
Claim 3
Dependent Claim
45 words
The method of claim 1 wherein said ingredient (ii) is selected from the group consisting of HF, HSiF 6 , HPF 6 , HBF 4 , K 2 ZrF 6 , K 2 TiF 6 , NH 4 F or NH 4 HF 2 .
Claim 4
Dependent Claim
32 words
The method of claim 1 wherein said electrolyte (b) further comprises one or more compounds selected from the group consisting of oxalic acid, aluminum nitrate, aluminum chloride, hydrogen peroxide and boric acid.
Claim 5
Dependent Claim
35 words
The method of claim 1 wherein said bath (a) further comprises one or more compounds selected from the group consisting of an ammonium, potassium, sodium or lithium persulfate, peroxydisulfate or disulfate, or a sulfonic acid.
Claim 6
Dependent Claim
21 words
The method of claim 1 wherein said ingredient (i) is present in an amount of from about 5% to about 25%.
Claim 7
Dependent Claim
16 words
The method of claim 1 wherein said step (a) is conducted for at least 5 seconds.
Claim 8
Dependent Claim
23 words
The method of claim 1 wherein said bath (a) is maintained at a temperature of from about 10° C. to about 95° C.
Claim 9
Dependent Claim
26 words
The method of claim 1 wherein said aluminum sheet is electrolyzed in said bath (a) using alternating or direct current at about 30-45 Amps/dm 2 .
Claim 10
Dependent Claim
23 words
The method of claim 1 wherein said electrolyte comprises nitric acid in a concentration of from about 3 g/l to about 500 g/l.
Claim 11
Dependent Claim
23 words
The method of claim 1 wherein said electrolyte comprises hydrochloric acid in a concentration of from about 3 g/l to about 100 g/l.
Claim 12
Dependent Claim
27 words
The method of claim 1 wherein the electrochemical graining step (b) is conducted with a current density of from about 30 to about 120 Amps/dm 2 .
Claim 13
Dependent Claim
38 words
The method of claim 1 wherein the anodizing step (c) employs an electrolyte having a temperature of from about 20° C. to about 80° C. and an acid concentration of from about 10% to about 20% by weight.
Claim 14
Dependent Claim
20 words
The method of claim 1 further comprising the step of applying a hydrophilizing interlayer composition to said sheet after anodizing.
Claim 15
Dependent Claim
28 words
The method of claim 13 wherein said interlayer composition is selected from the group consisting of polyvinyl phosphonic acid, sodium silicate and hydrofluozirconic acid and alkali zirconium fluorides.
Claim 16
Dependent Claim
21 words
The method of claim 1 further comprising the step of applying a lithographically suitable photosensitive composition to said treated aluminum sheet.
Claim 17
Dependent Claim
21 words
The method of claim 13 further comprising the step of applying a lithographically suitable photosensitive composition to said treated aluminum sheet.
Claim 18
Dependent Claim
19 words
The method of claim 15 wherein said photosensitive composition comprises an aromatic diazonium salt, quinone diazide or photopolymerizable compound.
Claim 19
Dependent Claim
12 words
The treated aluminum sheet produced according to the method of claim 1.
Claim 20
Dependent Claim
12 words
The treated aluminum sheet produced according to the method of claim 15.
Claim 21
Dependent Claim
12 words
The treated aluminum sheet produced according to the method of claim 16.
Claim 22
Dependent Claim
12 words
The treated aluminum sheet produced according to the method of claim 17.
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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) | 1988-03-04 | 1988-09-03 | 1989-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-04 | 1992-09-03 | 1993-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-04 | 1996-09-03 | 1997-03-05 | $7700.00 | Window Closed / Lapsed |