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US4630080A Expired / Lapsed US ⏱️ 0.0 years remaining

Heat-sensitive recording sheet

Assignee: Nippon Paper Industries Co Ltd
•
Filing: 1985-11-06
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Granted: 1986-12-16
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Expires: 2005-11-06
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Abstract

Abstract A heat-sensitive recording sheet comprising both calcium monobenzyl phthalate as stabilizer and 4-isopropoxy-4'-hydroxy diphenylsulfone and/or 4-methyl-4'-hydroxy diphenylsulfone as organic developer in heat-sensitive layer which comprises a basic colorless dyestuff and an organic developer. This heat-sensitive recording sheet provides the improved stability of developed color image against sticking of hair tonics and oils, etc.

Inventors

  • 👤 Toshimi Satake
  • 👤 Yoshihide Kimura
  • 👤 Toshiaki Minami
  • 👤 Fumio Fujimura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 22:35
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/30; B41M5/333; B41M5/3333; B41M5/3335; B41M5/3336; B41M5/337; B41M5/3377

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 91 words
A heat-sensitive recording sheet which comprises a support and a heat sensitive color-developing layer on at least one surface of said support, said heat-sensitive color layer containing a basic color-less dye and an organic developer as main components, characterized by comprising both calcium monobenzyl phthalate of the following general formula (III) as stabilizer and at least a compound selected from the group consisting of 4-isopropoxy-4'-hydroxy diphenylsulfone of the following general formula (I) and 4-methyl-4'-hydroxy diphenylsulfone of the following general formula (II) as said organic developer in said heat-sensitive coloring layer: ##STR4##
Claim 2
Dependent Claim 91 words
A heat-sensitive recording sheet which comprises a support and a heat sensitive color-developing layer on at least one surface of said support, said heat-sensitive color layer containing a basic color-less dye and an organic developer as main components, characterized by comprising both calcium monobenzyl phthalate of the following general formula (III) as stabilizer and at least a compound selected from the group consisting of 4-isopropoxy-4'-hydroxy diphenylsulfone of the following general formula (I) and 4-methyl-4'-hydroxy diphenylsulfone of the following general formula (II) as said organic developer in said heat-sensitive coloring layer: ##STR4##
Claim 3
Dependent Claim 31 words
A heat-sensitive recording sheet according to claim 1, wherein said calcium monobenzyl phthalate is added in an amount ranging from 10 to 60 wt % with respect to said organic developer.
Claim 4
Dependent Claim 34 words
A heat-sensitive recording sheet according to claim 1, wherein said basic colorless dye is at least a member selected from the group consisting of triphenylmethane leuco dye, fluoran leuco dyes and azaphthalide leuco dye.
Claim 5
Dependent Claim 31 words
A heat-sensitive recording sheet according to claim 1 or 3, wherein said basic colorless dye is at least a compound selected from the group consisting of 3-diethylamino-6-methyl-7-anilinofluorane, 3-(n-cyclohexyl-n-methylamino)-6-methyl(-7-anilinofluorane, 3-(n-ethyl-n-isoamyl)amino-6-methyl-7-anilinofluorane, and 3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindole-3-yl)-4-azaphthalide.
Claim 6
Dependent Claim 49 words
A heat-sensitive recording sheet according to claim 1, wherein said color-developing layer comprises 3-12 parts of 4-isopropoxy-4'-hydroxy diphenylsulfone, 1-4 parts of calcium monobenzyl phthalate and 1-20 parts of the filler per one part of said colorless basic dye, and 10-25 parts of the binder for the total solid content.
Claim 7
Dependent Claim 49 words
A heat-sensitive recording sheet according to claim 1, wherein said color-developing layer comprises 3-12 parts of 4-methyl-4'-hydroxy diphenylsulfone, 3-12 parts of calcium monobenzyl phthalate and 1-20 parts of the filler per one part of said colorless basic dye, and 10-25 parts of the binder for the total solid content.
Claim 8
Dependent Claim 17 words
A heat-sensitive recording sheet according to claim 1, wherein said color-developing layer further comprises an additional sensitizer.

References Cited (Backward Citations)

JPS58166098A Cited
US4536779A Cited
GB2142630A Cited
US4568766A Cited
EP0137982A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-12-15 1990-06-16 1990-12-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-12-15 1994-06-16 1994-12-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-12-15 1998-06-16 1998-12-16 $7700.00 Window Closed / Lapsed

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