Patent · US Expired

Polyurethane based inks for writing instruments

US6797748B2 · kind B2 · utility

4Cited by
38References
37Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 8, 2001
Grant dateSep 28, 2004
Priority date
Expiry dateJun 8, 2021

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09D11/18
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A non-erasable ink composition suitable for use in writing instruments is described comprising an isocyanate five thermoplastic polyurethane resin, a colorant and an organic solvent. The ink composition may also include a second resin, plasticizers, antioxidants, corrosion inhibitors, lubricants, chemical dispersants, and surfactants. The inks of the present invention exhibit a smooth writing performance and non-seepage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.