公开(公告)号：CA2033530A1

公开(公告)日：1991-07-13

申请号：CA2033530

申请日：1991-01-03

Applicant: HOECHST AG

Inventor： SCHWAB MICHAEL ,  KUBILLUS UWE

IPC: B05D7/14 ,  C08G18/00 ,  C08G18/08 ,  C08G18/10 ,  C08G18/12 ,  C09D5/00 ,  C09D5/02 ,  C09D175/04 ,  B05D7/16 ,  B05D7/26

Abstract: 139.171 AQUEOUS COATING COMPOSITION, ITS PREPARATION AND USE Aqueous coating compositions for preparing primers or primer surfacers containing at least one water-dispersible binder resin and crosslinking agents and optionally conventional additives, wherein at least some of the water-dispersible binder resin is a polyurethane resin containing structural units derived from (A) polyisocyanates, (B) polyols having an average molecular weight ?n of at least 400, (C) optionally low-molecular weight polyols, (D) compounds having at least two groups which are reactive toward isocyanato groups and at least one group which is capable of anion formation, (E) polyols carrying no other groups which are reactive with iso cyanato groups, these structural units (E) being in each case at the chain end of the polyurethane resin, (F) optionally compounds which are monofunctional or contain active hydrogen of varying reactivity and are different from (E), these structural units (F) likewise being at the chain end of the polyurethane resin and, (G) optionally compounds which are different from (B), (C), (D), (E) and (F) and contain at least two groups which are reactive with NCO groups. The primer surfacers obtainable therefrom are distinguished, inter alia, by improved stone chip resistance at low temperatures and by good interlayer adhesion, while the corresponding primers show improved corrosion protection.