Patent US4445998A successfully refreshed from Google Patents.
US4445998A
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Method for producing a steel lithographic plate
Assignee: Toyo Kohan Co Ltd
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Filing: 1981-12-02
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Granted: 1984-05-01
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Expires: 2001-12-02
Abstract
Abstract A method for producing a metal substrate for a lithographic plate is provided herein by treating the substrate having the thickness in the range of 50 to 400 μm. The said substrate is electrochemically, chemically or mechanically treated in order to provide an average surface roughness in the range of 0.1 to 3 μm, followed by a surface treatment such as plating or chemical treatment, and then followed by a conventional hydrophilic treatment.
Inventors
- 👤 Katsumi Kanda
- 👤 Katsunobu Kunimoto
- 👤 Keiji Yamane
- 👤 Yoshikazu Kondo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:33
CPC Classifications
C; C25; C25D; C25D5/00; C25D5/48; B; B41; B41N; B41N3/00; B41N3/03; C25D5/10; C25D5/12; C25D5/34; C25D5/36; C25D5/60; C25D5/615; C25D5/617; Y; Y10; Y10S; Y10S205/00; Y10S205/921
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
119 words
A method for producing a steel lithographic plate which consists essentially of: (a) subjecting a steel substrate having a thickness in the range of 50 to 400 cm, to a graining treatment by (i) electroplating with iron, (ii) etching in a solution containing ferric ions or (iii) mechanical treatment with sand or marble, in order to impart to said substrate an average surface roughness in the range of 0.1 to 3 μm, (b) imparting improved corrosion resistance to the substrate of step (a) by plating with a metal, an alloy or multi-layer of metals, and then (c) applying a hydrophilic coating with a suspension containing a water-dispersible sol of a metal compound to the treated substrate of step (b).
Claim 2
Independent Claim
119 words
A method for producing a steel lithographic plate which consists essentially of: (a) subjecting a steel substrate having a thickness in the range of 50 to 400 cm, to a graining treatment by (i) electroplating with iron, (ii) etching in a solution containing ferric ions or (iii) mechanical treatment with sand or marble, in order to impart to said substrate an average surface roughness in the range of 0.1 to 3 μm, (b) imparting improved corrosion resistance to the substrate of step (a) by plating with a metal, an alloy or multi-layer of metals, and then (c) applying a hydrophilic coating with a suspension containing a water-dispersible sol of a metal compound to the treated substrate of step (b).
Claim 3
Dependent Claim
42 words
The method according to claim 1, wherein said water-dispersible sol of a metal compound is at least one sol selected from the oxide or hydroxide of aluminum, titanium, zirconium, silicon, chromium, nickel, zinc, manganese, copper, cobalt, iron, lead, cadmium, magnesium or calcium.
Claim 4
Dependent Claim
18 words
The method according to claim 2, wherein the particle diameter of said sol is 1 to 500 mμ.
Claim 5
Dependent Claim
19 words
The method according to claim 3, wherein the concentration of said sol is 1 to 100 g/l as solids.
Claim 6
Dependent Claim
18 words
The method according to claim 1, wherein the suspension is stabilized by the addition of a stabilizing agent.
Claim 7
Dependent Claim
22 words
The method according to claim 5, wherein the stabilizing agent is an inorganic acid, an organic acid or a surface active agent.
Claim 8
Dependent Claim
20 words
The method according to claim 6, wherein the inorganic acid is chromic acid, phosphoric acid, chloric acid or sulphuric acid.
Claim 9
Dependent Claim
15 words
The method according to claim 6, an organic acid is citric acid or acetic acid.
Claim 10
Dependent Claim
29 words
The method according to claim 1, wherein the hydrophilic treatment of step (c) is performed by dipping or by electrolysis wherein said substrate of step (b) is the cathode.
Claim 11
Dependent Claim
15 words
The method according to claim 1, wherein said metal is chromium, nickel, tin or zinc.
Claim 12
Dependent Claim
22 words
The method according to claim 1, wherein said alloy is selected from the group consisting of chromium, nickel, copper, tin and zinc.
Claim 13
Dependent Claim
23 words
The method according to claim 1, wherein said multi-layer of metals is selected from the group consisting of chromium, nickel, tin and zinc.
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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) | 1987-05-01 | 1987-10-31 | 1988-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-01 | 1991-10-31 | 1992-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-01 | 1995-10-31 | 1996-05-01 | $7700.00 | Window Closed / Lapsed |