EP0147606A2
Expired / Lapsed
EP
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Phenazine leucodyes for electrochromic recording
Assignee: International Business Machines Corp
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Filing: 1984-11-16
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Granted: —
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Expires: 2004-11-16
Abstract
Abstract Certain phenazine leucodyes are useful in electrochromic recording systems. The specification discloses a leucodye having the structurewherein R is an acyl group having from 1 to 6 carbon atoms.
Inventors
- 👤 Paul Lewis Gendler
- 👤 Robert James Twieg
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 09:26
CPC Classifications
G; G01; G01D; G01D15/00; G01D15/06; B; B41; B41M; B41M5/00; B41M5/20
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
31 words
A substrate for electrochromic recording comprising bromide ions and characterized by also comprising a leucodye having the structure wherein R is an acyl group having from 1 to 6 carbon atoms.
Claim 2
Dependent Claim
31 words
A substrate for electrochromic recording comprising bromide ions and characterized by also comprising a leucodye having the structure wherein R is an acyl group having from 1 to 6 carbon atoms.
Claim 3
Dependent Claim
13 words
A substrate as claimed in claim 1 wherein R is a propionyl group.
Claim 4
Dependent Claim
17 words
A substrate as claimed in claim 1 or 2, wherein the leucodye is admixed with another leucodye.
Claim 5
Dependent Claim
14 words
A substrate as claimed in claim 1 or 2, wherein the substrate is paper.
Claim 6
Dependent Claim
29 words
A substrate as claimed in claim 4 wherein the leucodye is present at a concentration of about 20 mg per standard paper page of 8 1/2 by 11 inches.
References Cited (Backward Citations)
No citation records indexed.
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