Thinner is a volatile organic liquid, which is mainly used to dilute paint to facilitate construction. It is a mixed solvent composed of various solvents. The difference between diluents and solvents lies in their ability to dissolve certain main film-forming substances. Thinners only thin the existing paint, reduce the viscosity of the paint, and are generally added to the paint during application. The solvent can independently dissolve the film-forming substances in the paint, and as a component of the paint, it has been added to the paint product in a certain proportion. Secondly, the solvent contained in the paint may be used as a diluent for the paint, but some diluents may not necessarily be used as a solvent.
Adding diluent to the paint during construction will reduce the viscosity of the paint and the wet film thickness that can be obtained by ordinary construction methods. Also, due to dilution, the dry film thickness will decrease (actually a decrease in volume solids). This is the main reason against excessive thinning of paint, whether it is thinning paint for cold weather application, or thinning paint for so-called savings in paint consumption. In some cases, thinners are used to reduce costs. During construction, the diluent should leave the coating film before most of the main solvent evaporates, otherwise poor quality coating film will be produced.
Addition of thinner also increases the risk of solvent residues which, when evaporated from the paint, affect film formation. To thin the paint for application, only the thinner specified in the paint kit should be used. Any use of a different thinner requires the written consent of the paint manufacturer's technical representative.
