A baked finish is any thermoset coating that requires a heated cure (i.e. baking) after application to initiate a chemical reaction that cross-links the polymer. Heating methods include Infra red, convection and conductance. The temperature for baking generally ranges between 150 and 450 ° F.(66 to 232 ° C) depending on the type of coating and substrate. High temperature resistant (e.g. 800- 1200 ° F or 427 to 649 ° C.) silicone Painttypes can require higher temperatures to fully cure. Melamine and urea formaldehyde modified alkyd Painttypes are the most widely used baking finishes for metal furniture, electrical equipment, etc.
Basecoats/clearcoats systems are usually used in automotive body painting. The highly-pigmented basecoat is topcoated with multiple thin layers of clear finish (clearcoat) giving the final product depth and brilliance in color as well as an extremely durable finish. Minor scratches in the clearcoat can be buffed out without affecting the color coat or requiring repainting.
Basecoats can range from waterborne materials to two-component acrylic aliphatic urethanes; clear-coats are generally aliphatic urethane acrylic polymers.
A block filler is a high solids coating designed to fill or bridge cracks and holes in cementitious surfaces (commonly concrete blocks – except split-face) with minimal shrinkage upon curing. New concrete blocks normally cannot be filled or coated properly with general purpose paints. The surface of the blocks is covered with holes and gaps that require a high solids coating with good bridging and filling properties to reduce water penetration and allow for a smooth finish. Block fillers are widely available in latex and epoxy-based versions. The latex types are usually preferred for general purpose use due to their ease of handling; however, problems can arise due to the permeability and lack of water resistance seen in some types of block fillers that are overly filled with extender pigments. Extreme conditions and improper application, such as too heavy or multiple coats, can lead to the "shearing off' of less permeable finish coats such as alkyds or epoxies. Epoxy-based block fillers show the typical alkali, chemical, and solvent resistance of the epoxy.
Clear coating is the application of a transparent coating to provide protection from abrasion, staining, chemicals, or solvents. A “clear coat” finish is a transparent layer of material (often water white or of amber cast) applied over a colored basecoat that gives the surface depth and an added brilliance of color as well as durability.
Coil coating is a process that applies a coating to sheet metal that is subsequently rolled up in a coil for shipping and storage. There are many different types of Painttypes used in this method but all require a very fast setting or cure time, flexibility (for post forming processes) and corrosion resistance. These Painttypes can be in a liquid or powder form. In some sheet steel products, powder Painttypes are applied by electrostatic spray or fluidized bed methods. These methods reduce paint loss, solvent costs, and hazards associated with solvents. With the powder types, the coating is cured by baking. The liquid types can be air cured or baked. The coiled sheet is then further processed into roofing, siding, containers and various other products.
Conversion Painttypes are applied to metal to passivate the substrate and form an insoluble or non-reactive surface. Typical examples are vinyl wash primers that use phosphoric acid to passivate the metal surface and the vinyl butyral resin to cure. (see Wash Primer). There are also surface treatment materials that passivate metal surfaces without a binder, such as iron phosphate.
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