Patent EP0097220A2 successfully refreshed from Google Patents.
EP0097220A2
Expired / Lapsed
EP
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The stabilization of leucomethylene blue dyes on a printing substrate
Assignee: International Business Machines Corp
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Filing: 1983-02-23
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Granted: —
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Expires: 2003-02-23
Abstract
Abstract Substrates for printing are provided by stabilizing the leucomethylene blue dye contained therein with an additive selected from the group consisting of citric acid, aspartic acid, malonic acid, oxalic acid, ascorbic acid, tartaric acid, ketomalonic acid monohydrate, glucose and methionine.
Inventors
- 👤 Paul Lewis Gendler
- 👤 Annette Bronkesh Jaffe
- 👤 Robert James Twieg
- 👤 William Emmett Bernier
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 22:32
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/30; B41M5/337; B41M5/3375; B41M1/00; B41M1/26; B41M1/36; B41M5/124; B41M5/128; B41M5/20
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
45 words
A printing substrate comprising a leucomethylene blue dye characterized in that the substrate also includes a stabilizing amount of an additive selected from the group consisting of citric acid, aspartic acid, malonic acid, oxalic acid, ascorbic acid, tartaric acid, ketomalonic acid monohydrate, glucose and methionine.
Claim 2
Dependent Claim
45 words
A printing substrate comprising a leucomethylene blue dye characterized in that the substrate also includes a stabilizing amount of an additive selected from the group consisting of citric acid, aspartic acid, malonic acid, oxalic acid, ascorbic acid, tartaric acid, ketomalonic acid monohydrate, glucose and methionine.
Claim 3
Dependent Claim
27 words
A printing substrate as claimed in claim 1, wherein the stabilizer is present in a molar amount approximately equal to the molar amount of the leuco dye.
Claim 4
Dependent Claim
16 words
A printing substrate as claimed in claim 1 or 2, wherein the substrate material is paper.
Claim 5
Dependent Claim
18 words
A printing substrate as claimed in any one of claims 1 to 3, which also contains bromide ions.
References Cited (Backward Citations)
No citation records indexed.
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