Coil Coating Test Methods and how some Radiation Curable Coatings Fare

Introduction

Coil coating of steel is already promoted as an environmentally
friendly way to coat . Steel objects that are prepainted
require paint with lower solvent contents. Energy input is also
much reduced. Despite this the industry is being urged to reduce
solvent emissions even further and of course energy is expensive
so a reduction of this cost in itself is an important commercial
goal. It would appear that radiation curable coatings are an
ideal technical answer to the problem as these coatings are
solvent free and use energy efficiently. If there is such an
obvious case for the use of radiation curing in coil coating, why
have so few companies installed production facilities? The
answer may lie in the performance of the coatings currently
available when subjected to the rigours of the coil coating test
methods. This paper will highlight some of these tests, the
reasons for them and then address, by way of example, the
problems encountered when applying radiation cured coatings to
steel.