| 摘要 |
A process of painting a motor vehicle which comprises; (i) selecting and mixing two or more pigmented base paints from a series of master colours in predetermined proportions so as to obtain a paint pack having a desired final colour, each base paint comprising a hydroxyl functional polymer, optionally also adding an unpigmented blending clear comprising a hydroxyl functional polymer, (ii) adding (a) a tin catalyst for the reaction between isocyanate groups and hydroxyl groups, and (b) a polyfunctional thiol having at least three thiol groups, optionally one or both of these components being added as part of the blending clear, (iii) either before or after the tin catalyst and the polyfunctional thiol are added, adding a hardener comprising a polyisocyanate crosslinker, so as to form a thermosetting pigmented coating composition, (iv) applying a layer of the composition so formed to the surface of a vehicle, and (v) causing or allowing the layer to dry and cure, whereby the coating composition has an improved consistency of potlife irrespective of the pigments contained therein.
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