US3902976A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Corrosion and abrasion resistant aluminum and aluminum alloy plates particularly useful as support members for photolithographic plates and the like
Assignee: S O Litho Corp
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Filing: 1974-10-01
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Granted: 1975-09-02
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Expires: 1994-10-01
Abstract
Abstract A process for electrolytically forming on an aluminum or aluminum alloy sheet or plate a protective layer of film which is corrosion- and abrasion-resistant and provided with a hydrophilic surface. The process consists in first anodizing the aluminum or aluminum alloy sheet or plate in an electrolyte consisting of an aqueous solution of a mineral acid such as to form on the aluminum or aluminum alloy surface an aluminum oxide film, and subsequently electrolytically treating the film in an aqueous solution of sodium silicate, such as to form a durable abrasionresistant and corrosion-resistant barrier layer on the sheet or plate of aluminum or alluminum alloy which is hydrophilic and which prevents deterioration of a light sensitive diazo resin, or the like, placed as a photosensitive coating on the sheet or plate so as to form a presensitized lithographic plate.
Inventors
- 👤 John E Walls
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:58
CPC Classifications
B; B41; B41N; B41N3/00; B41N3/03; B41N3/034; C; C25; C25D; C25D11/00; C25D11/02; C25D11/04; C25D11/06; C25D11/12; C25F; C25F3/00; C25F3/02; C25F3/04
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
41 words
A METHOD OF MANUFACTURING PRESENSITIZED LITHOGRAPHIC PLATES, SAID METHOD COMPRISING THE STEPS OF GRAINING A SURFACE OF AN ALUMINUM ORAALUMINUM ALLOY PLATE, ANODIZING THE GRAINED SURFACE ELECTROLYTICALLY IN AN AQUEOUS ACIDIC SOLUTION, ANODICALLY TREATING THE ANODIZED SURFACE IN AN ALKALINE AQUE-
Claim 2
Independent Claim
41 words
A METHOD OF MANUFACTURING PRESENSITIZED LITHOGRAPHIC PLATES, SAID METHOD COMPRISING THE STEPS OF GRAINING A SURFACE OF AN ALUMINUM ORAALUMINUM ALLOY PLATE, ANODIZING THE GRAINED SURFACE ELECTROLYTICALLY IN AN AQUEOUS ACIDIC SOLUTION, ANODICALLY TREATING THE ANODIZED SURFACE IN AN ALKALINE AQUE-
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein said photosensitive material is a diazo resin.
Claim 4
Dependent Claim
44 words
The method of claim 1 wherein each of the steps of anodizing and anodically treating said plate is effected by connecting said plate and an electrode across a source of electrical energy such that said plate is anodic at least part of the Time.
Claim 5
Dependent Claim
25 words
The method of claim 1 wherein said aqueous acidic solution is a solution of sulfuric acid having a concentration in acid of 5% to 15%.
Claim 6
Dependent Claim
40 words
The method of claim 3 wherein said source of electrical energy is an AC source and said electrode is a second aluminum or aluminum alloy plate having a grained surface disposed proximate to the grained surface of the first plate.
Claim 7
Dependent Claim
18 words
The method of claim 4 wherein said aqueous acidic solution is maintained at a temperature of about 25*C.
Claim 8
Independent Claim
79 words
A method of manufacturing presensitized lithographic plates from a continuous web of aluminum or aluminum alloy, said method comprising the successive steps of cleaning said web, anodizing the grained surface of said web electrolytically in an aqueous acid solution, anodically treating the anodized surface in an alkaline aqueous solution of sodium silicate, rinsing said web, drying said web, coating the treated surface of said web with a photosensitive material, drying said coating and cutting said web to appropriate size.
Claim 9
Independent Claim
79 words
A method of manufacturing presensitized lithographic plates from a continuous web of aluminum or aluminum alloy, said method comprising the successive steps of cleaning said web, anodizing the grained surface of said web electrolytically in an aqueous acid solution, anodically treating the anodized surface in an alkaline aqueous solution of sodium silicate, rinsing said web, drying said web, coating the treated surface of said web with a photosensitive material, drying said coating and cutting said web to appropriate size.
Claim 10
Dependent Claim
13 words
The method of claim 7 wherein said photosensitive material is a diazo resin.
Claim 11
Dependent Claim
44 words
The method of claim 7 wherein each of the steps of anodizing and anodically treating said web is effected by connecting said web and an electrode across a source of electrical energy such that said web is anodic at least part of the time.
Claim 12
Dependent Claim
25 words
The method of claim 7 wherein said aqueous acidic solution is a solution of sulfuric acid having a concentration in acid of 5% to 15%.
Claim 13
Dependent Claim
18 words
The method of claim 10 wherein said aqueous acidic solution is maintained at a temperature of about 25*C.
Claim 14
Independent Claim
145 words
A method of manufacturing presensitized lithographic plates from a pair of continuous webs of aluminum or aluminum alloy, said method comprising the successive steps of cleaning of said webs, graining a surface of each of said webs, anodizing the grained surface of each of said webs electrolytically in an aqueous acidic solution, anodically treating the anodized surface in an alkaline aqueous solution of sodium silicate, rinsing each of said webs, drying each of said webs, coating the treated surface of each of said webs with a photosensitive material, drying the coating and cutting each of said webs to appropriate size, wherein said webs are disposed parallel to each other in the course of said anodizing, and said anodically the grained surface of said webs disposed toward each other, and said webs are electrically connected each to a terminal of an AC source of electrical energy.
Claim 15
Independent Claim
145 words
A method of manufacturing presensitized lithographic plates from a pair of continuous webs of aluminum or aluminum alloy, said method comprising the successive steps of cleaning of said webs, graining a surface of each of said webs, anodizing the grained surface of each of said webs electrolytically in an aqueous acidic solution, anodically treating the anodized surface in an alkaline aqueous solution of sodium silicate, rinsing each of said webs, drying each of said webs, coating the treated surface of each of said webs with a photosensitive material, drying the coating and cutting each of said webs to appropriate size, wherein said webs are disposed parallel to each other in the course of said anodizing, and said anodically the grained surface of said webs disposed toward each other, and said webs are electrically connected each to a terminal of an AC source of electrical energy.
Claim 16
Dependent Claim
25 words
The method of claim 12 wherein said aqueous acidic solution is a solution of sulfuric acid having a concentration in acid of 5% to 15%.
Claim 17
Dependent Claim
18 words
The method of claim 13 wherein said aqueous acidic solution is maintained at a temperature of about 25*C.
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) | 1978-09-01 | 1979-03-03 | 1979-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-01 | 1983-03-03 | 1983-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-01 | 1987-03-03 | 1987-09-02 | $7700.00 | Window Closed / Lapsed |