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Automotive finishing and re-finishing
Published in Andrew Livesey, Alan Robinson, The Repair of Vehicle Bodies, 2018
Spray lacquer coats as necessary using one light coat followed by a double header. Thin the enamel 2:3 to a viscosity of 16 to 19 seconds at 25°C. Use the appropriate thinner only. Should more than one coating of the lacquer be considered necessary, allow a flash-off time of 5 to 10 minutes between coats. The lacquer is touch dry after 15 minutes and can be safely handled after 1 to 2 hours, depending on room temperature. If necessary it can be burnished and polished after overnight drying, though this can be done after 4 to 6 hours if the enamel is force dried. The air pressure used when applying acrylic lacquer is between 3 bars (45 psi) and 4 bars (60 psi) depending on the make of spray gun employed.
Introduction to Experimental Stress Analysis
Published in Keith L. Richards, Design Engineer's Sourcebook, 2017
The advantages offered for using brittle lacquer is it can be applied to a wide range of materials, including metals, many plastics, glass, ceramics, and wood products. It is inexpensive and requires no instrumentation to analyze the results.
Finishing performance of Acacia mangium wood surface-treated with methanol
Published in The Journal of Adhesion, 2022
Redzuan Mohammad Suffian James, Paridah Md Tahir, Lee Seng Hua, Ummi Hani Abdullah, Mohd Khairun Anwar Uyup, Norwahyuni Mohd Yusof, Izwan Johari
There are three common types of wood finishes in wooden furniture, namely nitrocellulose (NC), acid catalysed (AC) and polyurethane (PU).[10] Nitrocellulose (NC) was made from an alkyd and nitrocellulose resin dissolved and then mixed with solvents that evaporate quickly.[10] This lacquer produces a very hard yet flexible, durable finish that can be polished to a high sheen. This lacquer, however, encompasses the hazardous nature of the solvent, which is flammable, volatile and toxic. The hazardous content also occurs during the manufacturing process.[11] NC lacquer is physically dry as solvents that evaporate from a paint film. NC can also be added to acid-catalysed lacquer to speed up the drying process. This type of lacquer has a moderate resistance to water, but is sensitive to heat and certain solvents. The main drawback is the tendency of the finish to yellow as it ages, which is clearly shown in light-coloured woods.[10] On the other hand, acid catalysed (AC) has a good resistance to household and industrial chemicals and a high resistance to discolouration. Typical AC lacquer is mainly made from alkyd and amino (urea or melamine) resins and is often combined with nitrocellulose. This two-pack acid catalyst is dry by means of a combination of solvent evaporation and chemical reactions, resulting in a hard, tough and mar-resistant film. With the use of heat, the curing time of AC lacquer can be dramatically accelerated. As far as polyurethane (PU) is concerned, this lacquer is typically hard, abrasion-resistant and durable coatings due to its polymerisation reaction on the surface of wood that forms chemical bonding with woof. This lacquer is popular for hardwood flooring, but some consider it difficult or unsuitable for finishing furniture or other details.[11] Polyurethane may be either one-component or two-component. As single-component lacquers dry, the isocyanate they contain reacts with air humidity. In two-component paints, the binder can be either polyester-type or acrylate. Acrylate-based paints dry more quickly than polyester-based paints. It is also stated in the literature that the highest adhesion of polyurethane lacquer is due to its polymerisation reaction on the surface of the wood, which forms a chemical bond with the wood, resulting in a stronger surface adhesion.[12]