Multicoat paints

The Anglian Water Authority lock gates at Little Paxton were similarly grit-blasted and sprayed with zinc to 100 p.m plus a multicoat paint system. 

In the majority of cases maximum durability will be produced by a multicoat system comprising priming and finishing paints only. Other considerations, however, such as uniformity of colour and smoothness of surface, may make it desirable to introduce intermediate coats, e.g. putty, filler and undercoat. The appearance of the final film or of the final painted structure is of some importance, and a final colour coat, which may contribute very little resistance to corrosion, may be necessary. 

Figure 9.6 The scratch resistances of the reference and hybrid system have been evaluated. The test has been performed in accordance to ISO 1518 standard (Paints and Varnishes - Scratch test) [62]. This standard specifies a test method for determining under defined conditions the resistance of a single coating or a multicoat system of paint, varnish or related product to penetration by scratching with a hemispherically tipped needle. Scratch resistance has been determined as the minimum load in grams required to cut through the film until the substrate. (Courtesy, Celine de Lame, CoRl).

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