Patent · US Expired

Modified polyurethane flow-under thermal transfer adhesive

US5061776A · kind A · utility

8Cited by
1References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 19, 1990
Grant dateOct 29, 1991
Priority date
Expiry dateNov 19, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P70/50
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A thermal transfer adhesive composition which is applied after electronic components have been installed on a printed wiring board, comprising: PA0 (a) 30 to 70 weight percent of an aliphatic diisocyanate or triisocyanate prepolymer; PA0 (b) 5 to 15 weight percent of a polyether diol or triol; PA0 (c) 20 to 40 weight percent of castor oil; PA0 (d) 5 to 20 weight percent of an epoxy resin containing 2 or more hydroxyl group; PA0 (e) 0.006 to 0.008 weight percent of a catalyst for the reaction of isocyanate groups with hydroxyl groups. The cured product is hydrolytically stable at 185.degree. F. and 95 percent relative humidity and has a good storage life when frozen. Alternatively, the composition may also include a pigment.

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