Nova Patents
WO0202700B1

Erasable inks, writing instruments, and methods

Abstract

Erasable inks are provided for use in a writing instruments. In one aspect, the inks include a solvent, and, dispersed in the solvent as a colorant, a pigment having a flake-like morphology, the ink being substantially free of other colorants.

Term

No projected expiry on record.

  1. Priority
  2. Filed
  3. Published
  4. Today

24 claims: 9 independent, 15 dependent

  1. 1
    33 AMENDED CLAIMS [received by the International Bureau on 8 March 2002 (08.03.02); original claims 1, 8, 14 and 21-26 amended; original claims 7, 13 and 20 cancelled; new claims 27 and 28 added; remaining claims unchanged (5 pages)] 1. An erasable ink for use in a writing instrument, comprising:a solvent, and a pigment having a flake-like morphology dispersed in the solvent, wherein the ink is substantially free of colorants other than said pigment, and wherein said ink has a shear-thinning index of between about 0.01 and about 0.8.
  2. 7
    8. An erasable ink for use in a writing instrument, comprising:a solvent, and a flake-like pigment having an average diameter from about 3 microns to about 12 microns dispersed in the solvent, wherein said ink has a shear-thinning index of between about 0.01 and about 0.8.
  3. 12
    14. An erasable ink for use in a writing instrument, comprising:a solvent, and a flake-like pigment having an average thickness of less than about 0.25 microns dispersed in the solvent, wherein said ink has a shear-thinning index of between about 0.01 and about 0.8.
  4. 14
    16. The ink of claim 14 wherein said pigment is selected from the group consisting of metal-oxide coated micas, graphites, and metal flake pigments.
  5. 18
    22. A method of forming an erasable marking on a paper substrate, comprising:making a marking on the substrate with a writing instrument containing an erasable ink comprising a solvent and a flake-like pigment having an average diameter from about 3 microns to about 12 microns dispersed in the solvent, wherein said ink has a shear-thinning index of between about 0.01 and about 0.8.
  6. 19
    23. A method of forming an erasable marking on a paper substrate, comprising:making a marking on the substrate with a writing instrument containing an erasable ink comprising a solvent and a flake-like pigment having an average thickness of less than about 0.25 microns dispersed in the solvent, wherein said ink has a shear-thinning index of between about 0.01 and about 0.8.
  7. 20
    24. A writing instrument, comprising:a reservoir containing an erasable ink comprising a solvent and a pigment having a flake-like moφhology dispersed in the solvent, wherein the ink is substantially free of colorants other than said pigment, and wherein said ink has a shear-thinning index of between about 0.01 and about 0.8.
  8. 21
    25. A writing instrument, comprising:a reservoir containing an erasable ink comprising a solvent and a flake- 36 like pigment having an average diameter from about 3 microns to about 12 microns dispersed in the solvent, wherein said ink has a shear- thinning index of between about 0.01 and about 0.8. 37
  9. 22
    26. A writing instrument, comprising:a reservoir containing an erasable ink comprising a solvent and a flakelike pigment having an average thickness of less than about 0.25 microns dispersed in the solvent, wherein said ink has a shear-thinning index of between about 0.01 and about 0.8.
  10. 23
    27. An erasable ink for use in a writing instrument, comprising:a solvent, a pigment having a flake-like moφhology dispersed in the solvent, wherein the ink is substantially free of colorants other than said pigment, and a shear-thinning additive selected from the group consisting of clays, organoclays, water dispersible gums, and high molecular weight polymers of acrylic acid.
Independent claims10