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US5919404A Expired / Lapsed US ⏱️ 0.0 years remaining

Reversible thermochromic compositions

Assignee: Pilot Ink Co Ltd
•
Filing: 1998-04-20
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Granted: 1999-07-06
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Expires: 2018-04-20
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Abstract

Abstract A reversible thermochromic composition comprising as essential components (a) an electron-donating color-developing organic compound, (b) at least one electron-accepting compound selected from alkoxyphenol compounds represented by Formula I: wherein R represents an alkyl group; and (c) a compound serving as a reaction medium capable of reversibly causing electron-donating/accepting reaction attributable to the components (a) and (b). This composition has a reversible metachromatic function that it presents a color-developed state when heated in a color-extinguished state and presents the color-extinguished state when temperature-dropped or cooled in the color-developed state, or that it begins to develop a color in the course of temperature drop after heating, having been triggered by its temperature rise when heated in a color-extinguished state, and returns to the color-extinguished state after it has presented a color-developed state in a maximum developed-color density.

Inventors

  • 👤 Katsuyuki Fujita
  • 👤 Yoshiaki Ono

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 17:17
CPC Classifications
C; C09; C09K; C09K9/00; C09K9/02; B; B41; B41M; B41M5/00; B41M5/26; B41M5/28; B41M5/287; B41M5/30; B41M5/305; B41M5/333; B41M5/3333; B41M5/3335; B41M5/337; B41M5/3375; C09D; C09D5/00; C09D5/26; B41M5/3372; Y; Y10; Y10S; Y10S252/00; Y10S252/962

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 69 words
A reversible thermochromic composition which develops color when heated and extinguishes color upon temperature decrease comprising; (a) an electron-donating color-developing organic compound; (b) at least one electron-accepting alkoxyphenol compound represented by Formula I: ##STR4## wherein R represents a straight-chain or branched alkyl group having 3 to 18 carbon atoms; and (c) a compound serving as a reaction medium which reversibly causes electron-donating/accepting reaction between the components (a) and (b).
Claim 2
Dependent Claim 69 words
A reversible thermochromic composition which develops color when heated and extinguishes color upon temperature decrease comprising; (a) an electron-donating color-developing organic compound; (b) at least one electron-accepting alkoxyphenol compound represented by Formula I: ##STR4## wherein R represents a straight-chain or branched alkyl group having 3 to 18 carbon atoms; and (c) a compound serving as a reaction medium which reversibly causes electron-donating/accepting reaction between the components (a) and (b).
Claim 3
Dependent Claim 21 words
The reversible thermochromic composition according to claim 1, wherein R is a straight-chain alkyl group having 8 to 12 carbon atoms.
Claim 4
Dependent Claim 32 words
The reversible thermochromic composition according to claim 1, wherein said component (c) contains at least one compound selected from a chain hydrocarbon, an alicyclic hydrocarbon, an aromatic hydrocarbon and a halogenated hydrocarbon.
Claim 5
Dependent Claim 16 words
The reversible thermochromic composition according to claim 1, which is encapsulated in the form of microcapsules.
Claim 6
Dependent Claim 40 words
The reversible thermochromic composition according to claim 1, which has a reversible metachromatic function that the composition presents a color-developed state when heated in a color-extinguished state and presents the color-extinguished state when temperature-dropped or cooled in the color-developed state.
Claim 7
Dependent Claim 23 words
The reversible thermochromic composition according to claim 5, wherein said reversible thermochromic composition is heated at a temperature not higher than 90° C.
Claim 8
Dependent Claim 61 words
The reversible thermochromic composition according to claim 1, which has a reversible metachromatic function that the composition begins to develop a color in the course of temperature drop after heating, having been triggered by its temperature rise when heated in a color-extinguished state, and returns to the color-extinguished state after it has presented a color-developed state in a maximum developed-color density.
Claim 9
Dependent Claim 28 words
The reversible thermochromic composition according to claim 7, wherein said reversible thermochromic composition is heated at a temperature not lower than the melting point of the component-(c) compound.

References Cited (Backward Citations)

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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) 2002-07-05 2003-01-04 2003-07-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-07-05 2007-01-04 2007-07-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-07-05 2011-01-04 2011-07-06 $7700.00 Window Closed / Lapsed

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