Influence of different parameters on the scratch resistance of UV coatings

Surface coatings have two functions: to decorate and to protect. So that coatings perform these functions for as long as possible we to try to devise ways of minimizing the mechanical erosion to
which they are subjected. Radiation-cured systems have made big gains in the coatings market in
recent years. Today they are of great importance in the furniture and parquet varnishes industry. Not so long ago much effort went into improving the abrasion resistance of floor varnishes; today it is their scratch resistance on which development work is being focussed. This paper investigates the effect of various parameters on the scratch resistance of UV coatings. Any suitable test must take into account the conditions to which the coated object is likely to be subjected. The Amtec-Kistler test, which simulates the conditions in a car wash, has now become the accepted method of testing the scratch resistance of automotive coatings. Unfortunately no uniform test exists for floor and furniture coatings. The many non-standard tests used today include, for example, quick tests with steel wool or other abrasive materials, the scratch resistance being assessm either visually or by measuring the residual gloss. In this investigation, an attempt was made to devise a simple method, using relatively simple equipment, which delivers reproducible results.