Other Automotive Coatings

The properties of coating systems used for car components differ considerably from those of systems used for exterior car surfaces. Color is not important (and is mainly black or gray), but anticorrosive properties similar to those of car body coatings are required. Since car components are produced in large numbers, coatings are commonly baked at high temperature to ensure a high reaction rate and rapid film formation. 

Wheels are electrocoated engine blocks are coated with heat-resistant, usually waterborne materials. Other parts (e.g., steering equipment and shock absorbers) are painted with two-pack, one-coat epoxy systems that are usually solventborne use of waterborne systems is, however, increasing. 

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Hydroxy functional methacrylates ate used in automotive coatings, dental resins, contact lenses (qv) and a variety of other appHcations (64). 

Compounds based on S—EB—S usually contain polypropylene, which improves solvent resistance and processibiUty and raises upper service temperatures. Compounds intended for use in the automotive industry are able to survive 1000 hours air exposure at temperatures of 125°C with only minor changes in properties (54). Very soft compounds have been developed to replace foam mbber for interior trim parts. In this and similar appHcations, these soft compounds are usually insert molded over polypropylene or metal and then coated with flexible polyurethane paint (55). Other automotive appHcations include products intended for sound deadening, flexible air ducts, and gear shifter boots, as weU as improving the properties of sheet mol ding compounds. 

Other NAD microspheres are composed of styrene, MMA, hydroxyethyl acrylate, acrylic acid and acrylonitrile and are blended with acrylic copolymers and melamine/formaldehyde resins [341,342]. Particles of this polymer are used as rheology modifiers to prevent sagging in automotive coatings and for controlling the orientation of metal flake pigments. 

The azo group (—N=N—) may be replaced by the analogous (—CH=N—) moiety to form an azomethine complex pigment, usually with copper as a chelating metal. The number of commercially available products in this group is also restricted. They typically afford yellow shades. Those species that provide the required lightfastness and weather resistance are used in automotive finishes and other industrial coatings. 

Chromium oxide is equally important as a colorant and in its other industrial applications. As a pigment, it is used predominantly in the paint and coatings industry for high quality green paints with special requirements, especially for steel constructions (coil coating), facade coatings (emulsion paints), and automotive coatings. 

Cellulose nitrate continues to be used in fine lacquers and automotive coatings. The nitrates are easy to produce, and simple mixtures with other polymers and plasticizers are readily formulated. Their use depends on the DS, which is detemuned via nitrogen content. The target-DS is adjusted via the water content maintained in the reaction mixture (O Fig. 19). Cellulose nitrates of low DS (10.9 to 11.7% nitrogen) provide for solubility in a range of organic solvents, and derivatives with high DS are used for gun cotton. 

Use Fuel for trucks, ships, and other automotive equipment, drilling muds, mosquito control (coating on breeding waters). 

Trimethylbicyclo-(2.2.1)hept-2-yl methacrylate. Monomers when cured providing hardness, low shrinkage, abrasion resistance, heat and water resistance, good weatherability in automotive coatings, electronics, adhesives, and other acrylic polymers. Liquid mp = -60° bp = 245° djfl = 0.983. Rhine Poulenc Surfactants Rit-Chem. 

The major use of SBR is in the production of tires, particularly passenger-car and light-truck tires, and in other automotive applications where SBR is blended with other elastomers. These applications include belts, hoses, seals, and various extruded and molded items. Nontire and nonautomotive uses of SBR are in industries that require hoses, belts, gaskets, or seals. Others include footwear (shoe soles) various kinds of solid wheels roll covers coated fabrics and electrical (wire and cable) insulation. 

Uses Acrylic for clear and pigmented coatings for vinyl and other substrates, plastic coatings, interior automotive coatings Features Water-borne coatings based on this prod, exhibit exc. adhesion to vinyl, plasticizer migration resistance films based on this prod, exhibit exc. water, alcohol, and chem. resist. 

Uses UV absorber/stabilizer for coatings, automotive coatings, styrenics, polyolefins, acrylic, unsat. polymers, PVC, PU, polyacetals, PVB, elastomers, other substrates, food pkg. adhesives Features Offers high solubility and desirable balance of props. Reguiatory FDA 21CFR 175.105... 

The automotive OEM (Original Equipment Manufacture) sector is one of the easiest paint subsectors to define, and is arguably the one with the highest public profile it includes all paints applied to the vehicle body shell in the paint shop of the manufacturer s production line. It does not include parts painted offline (e.g. plastic components, underbody or trim parts) or refinish items. The sector is dominated by car and light vans both in terms of unit volume production and paint tonnage used other commercial vehicles only account for about 15% of European automotive coating use the percentage is similar in the USA. 

Coatings are usually applied as multi-layered systems that are composed of primer and topcoat. However, in some cases - for example automotive coating systems -this may vary from four to six layers. Each coating layer is appHed to perform certain specific functions, though its activities are influenced by the other layers in the system. The interactions among different layers and the interfadal phenomenon play an important role in the overall performance of the multi-coat systems [5]. Different properties of coatings are typically associated with specific parts of a coating system (Fig. 1.1) [6]. 

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