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US5260139A Expired / Lapsed US ⏱️ 0.0 years remaining

Thermal image transfer recording medium

Assignee: Ricoh Co Ltd
•
Filing: 1990-11-16
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Granted: 1993-11-09
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Expires: 2010-11-16
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Abstract

Abstract A thermal image transfer recording medium is disclosed, which comprises a support; a releasing layer formed on the support, comprising a wax component; and a thermal image transfer layer formed on the releasing layer, comprising a copolymer prepared from an alkylmethacrylate and a (meth)acrylonitrile, optionally in addition thereto a vinyl monomer, with a glass transition temperature of 30° C. or more, and a coloring agent, the thermal image transfer layer having fine cracks having a length of 0.8 to 8 μm with the number thereof being 25 to 100 per 1000 μm 2 on the surface thereof. In this recording medium, the thermal image transfer layer may further comprise a crosslinked acrylic resin with a glass transition temperature of 10° C. or more and a number average molecular weight of 1,000,000 or more. Furthermore, an auxiliary thermal image transfer layer comprising a thermoplastic resin with a glass transition temperature of 30° C. or more may also be interposed between the releasing layer and the thermal image transfer layer.

Inventors

  • 👤 Shuhei Shiraishi
  • 👤 Shigeyuki Harada

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 20:46
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/40; B41M5/42; B41M5/423; B41M5/382; B41M5/392; B41M5/395; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10S428/914; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24893; Y10T428/26; Y10T428/266; Y10T428/31; Y10T428/31504; Y10T428/31551; Y10T428/31573; Y10T428/31583; Y10T428/31855

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 95 words
A thermal image transfer recording medium comprising: a support; a releasing layer formed on said support, comprising a wax component; and a thermal image transfer layer formed on said releasing layer, comprising a copolymer prepared from a group of copolymerizable components comprising an alkylmethacrylate and an acrylonitrile or methacrylonitrile, with a glass transition temperature of at least 30° C., and a coloring agent, said thermal image transfer layer having fine cracks having a length of 0.8 to 8 μm with the number thereof being 25 to 100 per 1000 μm 2 on the surface thereof.
Claim 2
Dependent Claim 95 words
A thermal image transfer recording medium comprising: a support; a releasing layer formed on said support, comprising a wax component; and a thermal image transfer layer formed on said releasing layer, comprising a copolymer prepared from a group of copolymerizable components comprising an alkylmethacrylate and an acrylonitrile or methacrylonitrile, with a glass transition temperature of at least 30° C., and a coloring agent, said thermal image transfer layer having fine cracks having a length of 0.8 to 8 μm with the number thereof being 25 to 100 per 1000 μm 2 on the surface thereof.
Claim 3
Dependent Claim 43 words
The thermal image transfer recording medium as claimed in claim 1, wherein said thermal image transfer layer further comprises a crosslinked acrylic resin with a glass transition temperature of at least 10° C. and a number average molecular weight of at least 1,000,000.
Claim 4
Dependent Claim 32 words
The thermal image transfer recording medium as claimed in claim 1, wherein said wax component contained in said releasing layer has a melting point or softening point of 70° to 120° C.
Claim 5
Dependent Claim 49 words
The thermal image transfer recording medium as claimed in claim 3, wherein said wax component contained in said releasing layer is selected from the group consisting of carnauba wax, montan wax, ozocerite, microcrystalline wax, rice bran wax, ceresine wax, paraffin wax, polyethylene wax, sazole wax, and hardened castor oil.
Claim 6
Dependent Claim 24 words
The thermal image transfer recording medium as claimed in claim 1, wherein said releasing layer has a thickness of 0.1 μm to 3 μm.
Claim 7
Dependent Claim 30 words
The thermal image transfer recording medium as claimed in claim 1, wherein said alkylmethacrylate is selected from the group consisting of methyl methacrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate.
Claim 8
Dependent Claim 46 words
The thermal image transfer recording medium as claimed in claim 1, wherein said coloring agent in said thermal image transfer layer is selected from the group consisting of carbon black, red iron oxide, Lake Red C, Fast Sky Blue, Benzidine Yellow, Phthalocyanine Green and Phthalocyanine Blue.
Claim 9
Dependent Claim 36 words
The thermal image transfer recording medium as claimed in claim 1, wherein the amount of said coloring agent is 10 wt. % to 20 wt. % of the total weight of said thermal image transfer layer.
Claim 10
Dependent Claim 26 words
The thermal image transfer recording medium as claimed in claim 1, wherein said thermal image transfer layer has a thickness of 1 μm to 3 μm.
Claim 11
Dependent Claim 19 words
The thermal image transfer recording medium as claimed in claim 1, wherein said releasing layer further comprises a lubricant.
Claim 12
Dependent Claim 31 words
The thermal image transfer recording medium as claimed in claim 10, wherein said lubricant is an inorganic lubricant selected from the group consisting of talc, mica powder, molybdenum disulfide and graphite.
Claim 13
Dependent Claim 26 words
The thermal image transfer recording medium as claimed in claim 11, wherein said inorganic lubricant has an average particle size of 0.1 μm to 5 μm.
Claim 14
Dependent Claim 80 words
The thermal image transfer recording medium as claimed in claim 10, wherein said lubricant is an organic lubricant having a melting point of at least 140° C., selected from the group consisting of lithium stearate, magnesium stearate, calcium stearate, strontium stearate, barium stearate, calcium laurate, barium laurate, lithium 12-hydroxystearate, calcium 12-hydroxystearate, zinc dibasic stearate, N,N'-ethylene-bis-12-hydroxystearic acid amide, N,N'-ethylene-bislauric acid amide, N,N'-methylene-bisstearic acid amide, N,N'-hexamethylene-bisstearic acid amide, N,N'-hexamethylene-bisoleic acid amide, N,N'-distearyladipic acid amide, N,N'-distearylterephthalic acid amide, polytetrafluoroethylene, and a silicone resin.
Claim 15
Dependent Claim 34 words
The thermal image transfer recording medium as claimed in claim 13, wherein the amount of said organic lubricant is 1 wt. % to 10 wt. % of the total weight of said releasing layer.
Claim 16
Dependent Claim 23 words
The thermal image transfer recording medium as claimed in claim 1, wherein said support has a thickness of 3 μm to 10 μm.
Claim 17
Dependent Claim 34 words
The thermal image transfer recording medium as claimed in claim 1, wherein said coloring agent in said thermal transfer layer is selected from the group consisting of direct dyes, oil-soluble dyes and basic dyes.

References Cited (Backward Citations)

US4707395A Cited
US4792496A Cited
JPH02178091A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-11-08 1997-05-10 1997-11-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-11-08 2001-05-10 2001-11-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-11-08 2005-05-10 2005-11-09 $7700.00 Window Closed / Lapsed

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