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US5196243A Expired / Lapsed US ⏱️ 0.0 years remaining

Printed matter

Assignee: Individual
•
Filing: 1992-02-21
•
Granted: 1993-03-23
•
Expires: 2012-02-21
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Abstract

Abstract Printed matters are disclosed, which are printed with the coloring ink that is able to do the short-time fading at which time the color is losen of itself in a relatively short time after once having developed color by interacting with the coloring assistant containing the pH-adjusting agent which loses effect with the passage of time due to the volatility or the desiccation, and further that is able to redevelop color and repeat the above-mentioned short-time fading each time when the above-mentioned coloring assistant is made to act thereon a plural number of times; and which printed matters are suitably used for printing invisibly, for example, the spaces for answers being to stand abreast of the visibly printed spaces for questions in question books.

Inventors

  • 👤 Kiyoharu Kawashima

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 13:15
CPC Classifications
G; G09; G09B; G09B3/00; G09B3/02; G09B3/04; B; B41; B41M; B41M3/00; B41M3/001; B44; B44F; B44F1/00; B44F1/08; B44F1/10; G09B19/00; G09B19/06; G09B19/08

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 112 words
Printed matter being printed with a coloring ink in which color is developed by interacting the ink with a coloring assistant containing a pH-adjusting agent and the color disappears by losing the pH-adjusting effect due to volatility or desiccation of the coloring assistant; said coloring ink consisting of 5 to 20 weight % of phthalein pH-indicator and ink vehicles containing, 8 to 20 weight % of surface active agent consisting of a mixture of sodium alkylether-sulfate ester, α-olefinsulfonate sodium, alkylarylsulfonateamide, and alkylamineoxide at same ratio, 10 to 26 weight % of alkylolamide, 0.12 to 2 weight % of citric acid, 0.12 to 2 weight % of rust preventives, and water as remainder.
Claim 2
Dependent Claim 112 words
Printed matter being printed with a coloring ink in which color is developed by interacting the ink with a coloring assistant containing a pH-adjusting agent and the color disappears by losing the pH-adjusting effect due to volatility or desiccation of the coloring assistant; said coloring ink consisting of 5 to 20 weight % of phthalein pH-indicator and ink vehicles containing, 8 to 20 weight % of surface active agent consisting of a mixture of sodium alkylether-sulfate ester, α-olefinsulfonate sodium, alkylarylsulfonateamide, and alkylamineoxide at same ratio, 10 to 26 weight % of alkylolamide, 0.12 to 2 weight % of citric acid, 0.12 to 2 weight % of rust preventives, and water as remainder.
Claim 3
Dependent Claim 70 words
Printed matters as set forth in claim 1, which is characterized in that said pH-adjusting agent which loses effect due to the volatility is either one sort or a mixture of plural sorts being selected from the group consisting of ammonia, monoethanol amine, a class of ethyl amines, a class of propyl amines, 2 ethylhexyloxypropyl amine, 3-ethoxypropyl amine, 3-methoxypropyl amine, diisobutyl amine, sec-butyl amine, and a class of ethylene amine.
Claim 4
Dependent Claim 45 words
Printed matters as set forth in claim 1, which is characterized in that said pH-adjusting agent that loses effect due to the evaporation is either one sort or a mixture of plural sorts being selected from the group consisting of diisopropanol amine, and diethanol amine.
Claim 5
Dependent Claim 22 words
Printed matters as set forth in claim 1, which is characterized in that said coloring assistant has within itself an acidic substance.
Claim 6
Dependent Claim 31 words
Printed matters as set forth in claim 4, which is characterized in that said acidic substance is a mixture of one having a volatile property and one having an involatile property.
Claim 7
Dependent Claim 25 words
Printed matter as set forth in claim 5, which is characterized in that said volatile acidic substance loses effect later than an alkaline pH-adjusting agent.
Claim 8
Dependent Claim 26 words
Printed matters as set forth in claim 1 wherein said color ink is characterized by having within itself an acidic substance acting as a pH-adjusting agent.
Claim 9
Dependent Claim 38 words
Printed matters as set forth in claim 7, which is characterized in that said pH-adjusting agent is either one sort or a mixture of plural sorts being selected from the groups consisting of tartaric acid and citric acid.

References Cited (Backward Citations)

US4188431A Cited
US4198445A Cited
US4162164A Cited
US4171982A Cited
US4490177A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-03-22 1996-09-21 1997-03-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-03-22 2000-09-21 2001-03-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-03-22 2004-09-21 2005-03-23 $7700.00 Window Closed / Lapsed

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