Preparation of soft and hard resins, and their use

US4220751A · kind A · utility

Assignee

• BASF SE

Inventors

• Harro Petersen · Bischofswerda, DE
• Kurt F. Fischer · Leonard, US
• Hans-Joachim Klug · Mutterstadt, DE
• Werner Trimborn · Schifferstadt, DE

Key dates

• Filing date: Dec 15, 1978
• Grant date: Sep 2, 1980
• Expiry date: Dec 15, 1998

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09D161/24
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for the preparation of soft and hard resins, and their use in surface-coating binders. According to the invention, soft and hard resins are prepared from a urea and a CH-acidic aldehyde by reacting a urea of the general formula (I) ##STR1## where X is oxygen or sulfur and R.sup.1 and R.sup.2 are hydrogen or identical or different alkyl, aryl or aralkyl, or may be an alkyleneurea radical, with at least 2 moles of a CH-acidic aldehyde of the general formula (II) ##STR2## where R.sup.3 is hydrogen and R.sup.4 is alkyl, aryl or aralkyl, or R.sup.3 and R.sup.4 are identical or different alkyl, aryl or aralkyl, in the presence of a strong acid, to give a condensation product, and then treating the latter with a base in an anhydrous medium. These soft and hard resins are used, in combination with other film-forming agents, as surface-coating binders.