Process for the production of back foamed internal parts for refrigeration furniture

US5269986A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Norbert Eisen · Hanerau-Hademarschen, DE
• Robert Zollner · Leverkusen, DE
• Wolfgang Henning · Zorneding, DE
• Reinhold Dederichs · Leverkusen, DE

Key dates

• Filing date: Apr 17, 1991
• Grant date: Dec 14, 1993
• Expiry date: Apr 17, 2011

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29K2995/0069
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

Refrigeration units having internal parts containing a rigid polyurethane foam formed without the use of perhalogenated fluoro-chlorohydrocarbons are produced by applying a coating to the internal walls of the part in which back-foaming will take place, pouring a foam forming reaction mixture into the cavity of the part in which the internal walls have been coated and allowing the foam to form and set. The coating applied to the internal walls of the part in which back foaming is to be carried out is selected from one-component chemically cross-linking lacquers, two-component chemically cross-linking lacquers and lacquers based on aqueous polyurethane dispersions. The foam forming mixture generally includes a polyisocyanate, a polyisocyanate-reactive compound and a blowing agent. The blowing agent must include a partially halogenated hydrocarbon having at least one carbon-hydrogen bond and a boiling point in the range of from about -50.degree. to about 50.degree. C.