Patent · US Expired

Purification of video disc lubricant additives

US4479851A · kind A · utility

1Cited by
9References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 10, 1982
Grant dateOct 30, 1984
Priority date
Expiry dateNov 10, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31663
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An improved process for the batch distillation or purification by stripping of a bis(hydroxyalkyl)disiloxane, which purified product is useful as a video disc lubricant additive or dopant. In accordance with the process, the feedstock of bis(hydroxyalkyl)disiloxane is subjected to a vacuum evaporation of the light volatiles by gradually reducing the pressure to about 2.times.10.sup.-1 Torr. After the low boiling materials have been distilled off, the temperature is gradually increased and the pressure gradually reduced (final temperature of about 135.degree. C. and final pressure of about 4.times.10.sup.-2 Torr) so as to produce a distill and having a viscosity of about 210.+-.30 centipoise at 25.degree. C.

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