Patent · US Expired

Eraser

US6441091B1 · kind B1 · utility

2Cited by
9References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 27, 2001
Grant dateAug 27, 2002
Priority date
Expiry dateJul 27, 2021

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08L53/025
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

An eraser composition comprising 22-41 wt % styrene-ethylene/butylene-styrene block copolymer, 5-15 wt % ethylene/propylene copolymer, 30-50 wt % calcium carbonate, 10-25 wt % factice; and 0.1-7 wt % pumice is provided. The eraser composition optionally contains up to 1 wt % titanium dioxide. The eraser composition preferably has a hardness of from 70 to 85 Shore A.

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