New UV curing systems for automotive applications

Recent developments of new UV curable resins, which meet the high demands of automotive applications (e.g. weather stability), in combination with a new lamp technology offer extremely fast drying of paints, giving complete curing within less than 2 min tin some cases even within seconds). Since the capacity of the painting/drying booth is the bottleneck in most body shops and OEM lines, this new technology offers a remarkable time saving advantage to the customer. The new technical standard is presented by a dual cure system due to the advantages of lower volume shrinkage and curing of shadow areas. The change of mar and chemical resistance depending on the amount of UV curable components in a one pack automotive clear coat is shown. The influence of both - temperature and distance between the lamp and the painted object has been investigated by the decrease of UV curable double bonds in a given dual cure refinishing clear coat. (C) 2000 Elsevier Science S.A. All rights reserved.