Nova Patents
EP0302497A2

Data recording medium.

Abstract

A data recording medium includes a recording layer which comprises a polymer liquid crystal and a metal chelate compound or soluble large cyclic colorant contained therein. The data recording medium shows a memory characteristic through utiliza­tion of phase transition between solid and a liquid crystal phase. The metal chelate compound or the soluble large cyclic colorant enhances the light-­absorption characteristic, especially in the near infrared region without imparing the performances of the polymer liquid crystal.

EP0302497A2, drawing sheet 1
Sheet 1 of 69

Term

Term ended

Projected expiry passed 4 August 2008, 18.1 years ago.

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11 claims: 1 independent, 10 dependent

  1. 1
    A data recording medium, comprising a recording layer which in turn comprises a polymer liquid crystal and a metal chelate compound or soluble large cyclic colorant contained therein.
  2. 2
    A medium according to Claim 1, wherein said metal chelate compound belongs to any one of the classes of metal chelate compounds represented by the following formulas (1) - (17):wherein R₁₅ denotes a hydrogen atom, hydroxyl group or alkyl group capable of being connected with another R₁₅;R₁₆ denotes alkyl group, halogen atom, hydrogen atom, nitro group, or benzo condensed group;and M denotes a center metal of Cu, Ni, Co or Pd. wherein R₁₇ denotes a hydrogen atom, hydroxyl group, alkyl group or aryl group capable of being connected with another R₁₇;R₁₈ denotes a halogen atom, alkyl group, nitro group or condensed benzo group;and M denotes Cu, Ni, Co or Pd. wherein R₁₉ denotes an alkyl group or aryl group;R₂₀ denotes a hydrogen atom, halogen atom, alkyl group, aryl group, nitro group or condensed benzo group;and M denotes Cu, Ni or Pd. wherein R₂₁ denotes an alkyl group or aryl group;R₂₂ denotes a hydrogen atom, halogen atom, alkyl group or condensed benzo group;and M denotes Cu, Ni or Pd. wherein R₂₃ denotes a hydrogen atom or alkyl group;and M denotes Cu or Ni. wherein R₂₄ denotes a hydrogen atom or alkyl group;and M denotes Cu, Ni, Co or Mn. wherein R₂₅ and R₂₆ respectively denote a substituted or non-substituted alkyl group, acyl group or aryl group and R₂₅ and R₂₆ are capable of forming an aromatic ring in combination;M denotes Cu, Ni, Co or Pd which can have a charge and a counter ion. wherein R₂₇ denotes a sulfur atom, substituted or non-­substituted amino group, oxygen atom or thioketone group;R₂₈ denotes a hydrogen atom, alkyl group, halogen atom or amino group;and M denotes Zn, Cu or Ni. wherein R₂₉ denotes an alkyl group, aryl group or styryl group;and M denotes Cu, Ni or Co. wherein R₃₀ denotes a hydrogen atom, halogen atom, alkyl group, acyl group or aryl group;and M denotes Ni or Zr. wherein R₃₁ denotes an alkyl group or aryl group;and M denotes Cu, Ni or Co. wherein R₃₂ and R₃₃ respectively denote an alkyl group or aryl group;and M denotes Ni. wherein R₃₄ and R₃₅ respectively denote an alkyl group, amino group, aryl group or furan group capable forming an alicyclic ring in combination with each other;and M denotes Ni. wherein R₃₆ and R₃₇ denote a hydrogen atom, halogen atom or alkyl group;X denotes an oxygen atom or sulfur atom;and M denotes Ni. wherein R₃₈ and R₃₉ respectively denote a hydrogen atom, alkyl group, halogen atom or nitro group;X denotes an oxygen atom or sulfur atom;M denotes Ni;and Y ⊕ denotes a quarternary ammonium cation. wherein R₄₀ denotes an amino group;and M denotes Cu, Ni, Co or Pd. wherein R₄₁ denotes a hydrogen atom, halogen atom, alkyl group, acyl group, nitro group or alkoxyl group;and M denotes Zn, Cu, Ni or Co.
  3. 3
    A medium according to Claim 1, wherein said metal chelate compound is a metal phthalocyanine or metal naphthalocyanine.
  4. 4
    A medium according to Claim 1, wherein said metal chelate compound is added in a proportion of 0.01 - 10 wt. % of the liquid crystal.
  5. 5
    A medium according to Claim 1, wherein said soluble large cyclic colorant is a soluble azaanulene.
  6. 6
    A medium according to Claim 1, wherein said soluble large cyclic colorant is a soluble colorant selected from the group consisting of phthalocyanines, naphthalocyanines, porphyrines and tetrabenzopophyrines.
  7. 7
    A medium according to Claim 1, wherein said soluble large cyclic colorant is added in a proportion of 0.01 - 40 wt. % of the liquid crystal.
  8. 8
    A medium according to Claim 1, wherein said soluble large cyclic colorant is added in a proportion of 0.1 - 25 wt. % of the liquid crystal.
  9. 9
    A medium according to Claim 1, wherein said polymer liquid crystal is a ferroelectric polymer liquid crystal.
  10. 10
    A medium according to Claim 1, wherein said soluble large cyclic colorant is a colorant selected from phthalocyanines and naphthalocyanines which are inclusively represented by the following formula (I):wherein the symbols A, B, C and D respectively denote the following divalent group: wherein R₁ - R₂₀ respectively denote a hydrogen group, a linear or branched alkyl, alkoxy or alkenyl group having 4 - 20 carbon atoms, or a group selected from the following: -SiQ₁Q₂Q₃, -SQ₄, -COQ₅, COOQ₆, and -NQ₇Q₈, wherein Q₁ - Q₈ respectively denote a hydrogen atom, or a linear or branched alkyl or alkenyl group having 1 - 20 carbon atoms;M denotes Ge, Sn, transition metal, Al, Ga, In, alkaline earth metal, lanthanide element or actinide element, or an oxide, halogenide or alkoxide thereof.
  11. 11
    A medium according to Claim 1, wherein said soluble cyclic colorant is a naphthalocyanine represented by the following formula (II):wherein M denotes Ge, Sn, transition metal, Al, Ga, In, alkaline earth metal, lanthanide element or actinide element;X denotes halogen atom, alkyl group, carboxyl group, alkoxy group, ether group or alkenyl group, etc.;Xm₁ - Xm₄ respectively denote halogen atom, alkyl group, sulfomoyl group, ether group or alkenyl group;a - d are respectively a number of 0 - 4 satisfying the relationship of a+b+c+d ≧ 1.
Independent claims11