Aqueous coating compositions and their use for the preparation of coatings that are permeable to water vapor

US5716676A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Detlef-Ingo Schutze · Recklinghausen, DE
• Wilhelm Thoma · Leverkusen, DE
• Klaus Nachtkamp · Cologne, DE
• Josef Pedain · Cologne, DE
• Reinold Schmitz · Blecher, DE

Key dates

• Filing date: Nov 18, 1996
• Grant date: Feb 10, 1998
• Expiry date: Nov 18, 2016

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31591
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention relates to the use of coating compositions to prepare coatings having water vapor permeabilities of at least 2500 g/m.sup.2 per day (DS 2109 TM1 method) containing PA1 (A) a polyurethane containing (1) 0.1 to 75 meq/100 g of ionic groups and (2) 11 to 50% by weight of --(CH.sub.2 CH.sub.2 O).sub.n -- units (wherein n is 2 to 25) incorporated into the main chain prepared from reactive components comprising PA2 (I) one or more polyisocyanates, PA2 (II) one or more polyols having a number average molecular weight of 350 to 5000, with the proviso that if any such polyol is a sulfonated polyether diol having the formula ##STR1## in which R is hydrogen or an organic group having 1 to 8 carbon atoms, m and n are 1 to 10, p is 0, 1, or 2, and M is ammonium or alkali metal cation, then an additional ethoxy-containing polyether polyol must also be present, and PA2 (III) one or more chain lengthening agents having a molecular weight of 32 to 349; and PA1 (B) 30 to 80% by weight, based on the sum of components (A) and (B), of an aqueous phase.