Paint-bake process

Manufacturers Comments Fast RT cure. Strong tough bond, withstands bending. Cures tack-lree. Withstands paint-bake process, can I... 

Antiflutter adhesives are used to adhere and isolate outer body panels (i.e., hoods, doors and deck lids) from inner reinforcements. They need to adhere to steel contaminated with stamping lubricants and be resistant to washont from phosphate cleaning systems. Many of these adhesives are designed to expand during the paint-bake process. Heat-cnrable rubber formnlations are used commonly, inclnding SBR and polybntadiene. 

The physical properties of automotive enamels are in large part determined by the crosslink structure developed in the paint films during the baking process. Enamels which are not cured sufficiently (undercured) are generally sensitive to humidity and solvents. In addition, they may be prone to chipping and cold cracking. Faints which have been baked excessively (overcured) exhibit intercoat adhesion failure. That is, subsequent coats... 

Zinc arc spraying is an inexpensive process in terms of equipment and raw materials. Only 55—110 g/m is required for a standard 0.05—0.10 mm Zn thickness. It is more labor intensive, however. Grit blasting is a slow process, at a rate of 4.5 m /h. AppHcation of an adhesive paint layer is much quicker, 24 m /h, although the painted part must be baked or allowed to air dry. Arc sprayed 2inc is appHed at a rate of 9—36 m /h to maintain the plastic temperature below 65°C. The actual price of the product depends on part complexity, number of parts, and part size. A typical price in 1994 was in the range of 10—32/m. ... 

Most metals receive a base coat of enamel (or occasionally paint), which is baked on. Printing then takes place on the enamel coating by offset lithography, dry offset letterpress, and occasionally other processes. 

The commercial demand for pigments which tend to bleed is limited. A major consideration is the processing temperature in a particular medium. There are a number of baking paints, for instance, which do not bleed into a white coating if they are cured at 120°C while a certain extent of bleeding is observed at temperatures between 140 and 160°C. 

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