Patent · US Expired

Polyurethane rim system

US4426348A · kind A · utility

14Cited by
5References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 29, 1982
Grant dateJan 17, 1984
Priority date
Expiry dateJul 29, 2002

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G2120/00
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A polyurethane RIM system has at least two molding stations. The reactants are brought to the mixheads as three separate streams. One stream contains the isocyanate, the second stream contains some of the polyol, the chain extender and crosslinker and a third stream contains additional amounts of the polyol, along with what additives might be desired. At each mixhead the proportions of ingredients are controlled to give an isocyanate index of about 100, but the ratio of one polyol stream to the other is regulated to control the flex modulus and other properties of the molded product as may be desired. In this way, one source of supply can be used to feed several molding stations, each of wich may produce a product of different physical properties and thus of different costs.

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