General disadvantages

1. The majority is two-pack materials that must be mixed correctly before use;

2. Their cure, overcoating properties, pot life (e.g. the time the mixed components are usable) are all temperature dependent. This means, for example, that an increase of 10°C can halve the reaction times;

3. They are more difficult to overcoat then most types, and this can lead to problems of intercoat adhesion. Cured films require abrading before subsequent coats will adhere;

4. As a rule, they cannot be applied over other types of paint;

5. The high cohesive strength developed during the curing of these materials tends to place stress on their adhesive properties.

Therefore, unless they are specifically modified they require a higher standard of surface preparation than other types of paint.

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