← Back to Patent Explorer
US5849651A Expired / Lapsed US ⏱️ 0.0 years remaining

Reversible thermal recording medium

Assignee: Toshiba Corp
•
Filing: 1996-05-31
•
Granted: 1998-12-15
•
Expires: 2016-05-31
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A reversible thermal recording medium comprises a composition containing a color former, a developer, a reversible material capable of reversibly changing the state of the composition by supplying heat energies with two different values, and, as required, a phase separation controller which permits changing the phase separation speed of the developer at temperatures in the vicinity of the melting point of the phase separation controller, at least 80% by weight of the reversible material being a sterol compound in which the carbon-to-carbon bond between 2- and 3-positions of the stroid skeleton is a single bond, the carbon-to-carbon bond between 3- and 4-positions of the steroid skeleton is a single bond, a hydroxyl group is attached to the carbon atom in at least the 3-position of the steroid skeleton, and a specified chemical structure is bonded at 16- and 17-positions of the stroid skeleton, and the phase separation controller being provided by a low molecular organic material, the maximum carbon chain length there of being at least 10.

Inventors

  • 👤 Satoshi Takayama
  • 👤 Sawako Fujioka
  • 👤 Tetsuo Okuyama
  • 👤 Hideyuki Nishizawa
  • 👤 Hirohisa Miyamoto
  • 👤 Masami Sugiuchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 19:31
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/30; B41M5/337; B41M5/3375

Claims Analysis

Total Claims: 29
Claim 1
Independent Claim 135 words
A reversible thermal recording medium, comprising a composition containing a color former, a developer, and a reversible material capable of reversibly changing the state of said composition by supplying heat energies with two different values or by providing two different heat histories, at least 80% by weight of said reversible material being a sterol compound in which the carbon-to-carbon bond between 2- and 3-positions of the steroid skeleton represented by structural formula (1) given below is a single bond, the carbon-to-carbon bond between 3- and 4-positions of said steroid skeleton is a single bond, a hydroxyl group is attached to the carbon atom in at least the 3-position of the steroid skeleton, and at least one of chemical structures (A) to (D) given below is bonded at 16- and 17-positions of the steroid skeleton: ##STR3##
Claim 2
Dependent Claim 135 words
A reversible thermal recording medium, comprising a composition containing a color former, a developer, and a reversible material capable of reversibly changing the state of said composition by supplying heat energies with two different values or by providing two different heat histories, at least 80% by weight of said reversible material being a sterol compound in which the carbon-to-carbon bond between 2- and 3-positions of the steroid skeleton represented by structural formula (1) given below is a single bond, the carbon-to-carbon bond between 3- and 4-positions of said steroid skeleton is a single bond, a hydroxyl group is attached to the carbon atom in at least the 3-position of the steroid skeleton, and at least one of chemical structures (A) to (D) given below is bonded at 16- and 17-positions of the steroid skeleton: ##STR3##
Claim 3
Dependent Claim 78 words
The reversible thermal recording medium according to claim 1, wherein said composition further contains a phase separation controller which permits changing the phase separation speed of said color former or said developer at temperatures in the vicinity of the melting point of said phase separation controller, said phase separation agent being highly crystallizable, having a low molecular weight and comprising a long-chained alkyl group having a minimum carbon chain length of 10 and at least one polar group.
Claim 4
Dependent Claim 35 words
The reversible thermal recording medium according to claim 2, wherein said phase separation controller is contained in an amount of 1 to 50 parts by weight relative to 1 part by weight of said developer.
Claim 5
Dependent Claim 25 words
The reversible thermal recording medium according to claim 2, wherein said phase separation controller is a linear, aliphatic alcohol having at least one hydroxyl group.
Claim 6
Dependent Claim 34 words
The reversible thermal recording medium according to claim 2, wherein said phase separation controller is a linear, aliphatic diol having hydroxyl groups attached to the carbon atoms at both ends of the carbon chain.
Claim 7
Dependent Claim 20 words
The reversible thermal recording medium according to claim 2, wherein said phase separation controller has at most 36 carbon atoms.
Claim 8
Dependent Claim 24 words
The reversible thermal recording medium according to claim 2, wherein said phase separation controller has a melting point of 70° C. to 120° C.
Claim 9
Dependent Claim 34 words
The reversible thermal recording medium according to claim 1, wherein said developer is contained in an amount of 0.1 to 10 parts by weight relative to 1 part by weight of said color former.
Claim 10
Dependent Claim 34 words
The reversible thermal recording medium according to claim 1, wherein said reversible material is contained in an amount of 1 to 200 parts by weight relative to 1 part by weight of said developer.
Claim 11
Dependent Claim 34 words
The reversible thermal recording medium according to claim 9, wherein said reversible material is contained in an amount of 3 to 30 parts by weight relative to 1 part by weight of said developer.
Claim 12
Dependent Claim 80 words
A reversible thermal recording medium, comprising a composition consisting of a color former, a developer and a phase separation controller which permits changing the phase separation speed of said color former or said developer at temperatures in the vicinity of the melting point of said phase separation controller, said phase separation controller being highly crystallizable, having a low molecular weight and comprising a long-chained alkyl group having a minimum carbon chain length of 10 and at least one polar group.
Claim 13
Dependent Claim 80 words
A reversible thermal recording medium, comprising a composition consisting of a color former, a developer and a phase separation controller which permits changing the phase separation speed of said color former or said developer at temperatures in the vicinity of the melting point of said phase separation controller, said phase separation controller being highly crystallizable, having a low molecular weight and comprising a long-chained alkyl group having a minimum carbon chain length of 10 and at least one polar group.
Claim 14
Dependent Claim 17 words
The reversible thermal recording medium according to claim 11, wherein said composition further contains a reversible material.
Claim 15
Dependent Claim 25 words
The reversible thermal recording medium according to claim 11, wherein said phase separation controller is a linear aliphatic alcohol having at least one hydroxyl group.
Claim 16
Dependent Claim 34 words
The reversible thermal recording medium according to claim 13, wherein said phase separation controller is a linear aliphatic diol having hydroxyl groups attached to the carbon atoms at both ends of the carbon chain.
Claim 17
Dependent Claim 20 words
The reversible thermal recording medium according to claim 11, wherein said phase separation controller has at most 36 carbon atoms.
Claim 18
Dependent Claim 29 words
The reversible thermal recording medium according to claim 11, wherein said phase separation controller has a melting point falling within a range of between 70° C. and 120° C.
Claim 19
Dependent Claim 179 words
A reversible thermal recording medium, comprising a composition containing a color former, a developer, and a reversible material, said reversible material being provided by a benzophenone compound represented by general formula (2) given below: ##STR4## where R 1 and R 2 , which are the same or different, are selected from the group consisting of a halogen atom, an alkyl group, an alkoxy group, an amino group and a hydroxyl group, and m and n, which are the same or different, denote integers of 0 to 5, at least one of R 1 and R 2 being a hydroxyl group, and at least one of m and n not being zero, said composition further containing a phase separation controller which permits changing the phase separation speed of said color former or said developer at temperatures in the vicinity of the melting point of said phase separation controller, said phase separation agent being highly crystallizable, having a low molecular weight and comprising a long-chained alkyl group having a minimum carbon chain length of 10 and at least one polar group.
Claim 20
Dependent Claim 179 words
A reversible thermal recording medium, comprising a composition containing a color former, a developer, and a reversible material, said reversible material being provided by a benzophenone compound represented by general formula (2) given below: ##STR4## where R 1 and R 2 , which are the same or different, are selected from the group consisting of a halogen atom, an alkyl group, an alkoxy group, an amino group and a hydroxyl group, and m and n, which are the same or different, denote integers of 0 to 5, at least one of R 1 and R 2 being a hydroxyl group, and at least one of m and n not being zero, said composition further containing a phase separation controller which permits changing the phase separation speed of said color former or said developer at temperatures in the vicinity of the melting point of said phase separation controller, said phase separation agent being highly crystallizable, having a low molecular weight and comprising a long-chained alkyl group having a minimum carbon chain length of 10 and at least one polar group.
Claim 21
Dependent Claim 25 words
The reversible thermal recording medium according to claim 17, wherein said phase separation controller is a linear, aliphatic alcohol having at least one hydroxyl group.
Claim 22
Dependent Claim 34 words
The reversible thermal recording medium according to claim 17, wherein said phase separation controller is a linear, aliphatic diol having hydroxyl groups attached to the carbon atoms at both ends of the carbon chain.
Claim 23
Dependent Claim 20 words
The reversible thermal recording medium according to claim 17, wherein said phase separation controller has at most 36 carbon atoms.
Claim 24
Dependent Claim 24 words
The reversible thermal recording medium according to claim 17, wherein said phase separation controller has a melting point of 70° C. to 120° C.
Claim 25
Dependent Claim 126 words
A reversible thermal recording medium, comprising a composition containing a color former, a developer provided by a benzophenone compound having a phenolic hydroxyl group, a reversible material provided by a steroid compound in which the carbon-to-carbon bond between 2- and 3-positions of the steroid skeleton is a single bond, the carbon-to-carbon bond between 3- and 4-positions of said steroid skeleton is a single bond, and both a hydroxyl group and a --OCOCH 3 group are attached to the carbon atom in the 3-position of the steroid skeleton, and a phase separation controller provided by a highly crystallizable, low molecular weight linear aliphatic diol having hydroxyl groups attached to the carbon atoms at both ends of the carbon chain having a minimum carbon chain length of 10.
Claim 26
Dependent Claim 126 words
A reversible thermal recording medium, comprising a composition containing a color former, a developer provided by a benzophenone compound having a phenolic hydroxyl group, a reversible material provided by a steroid compound in which the carbon-to-carbon bond between 2- and 3-positions of the steroid skeleton is a single bond, the carbon-to-carbon bond between 3- and 4-positions of said steroid skeleton is a single bond, and both a hydroxyl group and a --OCOCH 3 group are attached to the carbon atom in the 3-position of the steroid skeleton, and a phase separation controller provided by a highly crystallizable, low molecular weight linear aliphatic diol having hydroxyl groups attached to the carbon atoms at both ends of the carbon chain having a minimum carbon chain length of 10.
Claim 27
Dependent Claim 75 words
A reversible thermal recording medium, comprising a composition consisting of a color former, a developer, a reversible material, and a phase separation controller, the difference between the melting point and the solidifying point of said phase separation controller being at least 10° C., said phase separation agent being highly crystallizable, having a low molecular weight and comprising a long-chained alkyl group having a minimum carbon chain length of 10 and at least one polar group.
Claim 28
Dependent Claim 75 words
A reversible thermal recording medium, comprising a composition consisting of a color former, a developer, a reversible material, and a phase separation controller, the difference between the melting point and the solidifying point of said phase separation controller being at least 10° C., said phase separation agent being highly crystallizable, having a low molecular weight and comprising a long-chained alkyl group having a minimum carbon chain length of 10 and at least one polar group.
Claim 29
Dependent Claim 23 words
The reversible thermal recording medium according to claim 23, wherein said phase separation controller is a mixture of at least two different compounds.

References Cited (Backward Citations)

US5296439A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-12-14 2002-06-15 2002-12-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-12-14 2006-06-15 2006-12-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-12-14 2010-06-15 2010-12-15 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag