Motor car finishes

There are some similarities between coil finishing and original motor car finishes both are required to give good exterior durability and both can be... 

Acrylic resins used with MF resin are flexible copolymers containing at least one hard and one soft monomer, a hydroxyl-containing monomer to provide reactive sites and possibly an acid monomer (see p. 151 for examples). They may be used as solutions in solvent or as non-aqueous dispersions. They produce extremely durable motor car finishes which can be polished to some extent. 

The modern motor car is made from steel, zinc or zinc alloy-coated steel and some plastic parts, all of which require painting. The main component is the body shell, made from the above metals, and this is coated in a continuous production process. A full finishing system with all four coatings is usually applied for maximum protection and a high quality appearance. 

If a motor car has to be refinished after repair, commonsense suggests that the original finishing system would be ideal for maintenance of protection and durability. However, with tyres, upholstery, fabric and plastic trim fitted and petrol in the tank, the use of such high stoving temperatures is not practical. The practical upper temperature limit is 80°C. This means that none of the original materials is suitable, not even the acrylic lacquer, since this is designed to be sanded and the scratches reflowed at 155 C. 

These requirements are usually met with two-pack paints based on hydroxyl-rich polyester or acrylic resins in the pigmented pack and aliphatic polyisocyanates in the activator pack. Cure with this type of finish is relatively fast and complete even at low ambient temperatures. An alternative finish is an acrylic lacquer, similar to the lacquer used for refinishing motor cars. These finishes are applied to the assembled aircraft by operators protected by air-fed hoods and using airless or conventional spray guns. High durability pigments are included. 

Many automotive applications require the part to be coated at the same time and with the same finish as the rest of the assembled metal components and so such finishes will have the durability normally associated with the modern motor car, provided that they continue to adhere. 

Table 11.2 Formulations of nitrocellulose glossy wood finish and acrylic motor car lacquer... 

TPL-SB are low-solids (12-18% by volume) solution coatings that have given brilliant metallic finishes for many years. Their properties were maintained when the major user. General Motors, went over to TPL-NAD. TSE-SB, the solution enamel used originally by Ford, Chrysler, and American Motors, is now virtually extinct as a topcoat for U.S. passenger cars. It has been replaced by TSE-NAD, which has higher solids and lower emission characteristics. 

On American business abroad in the 1920s, see Wilkins (ref. 7). This book has data on Du Font s overseas activities Du Pont invested abroad in niches where it had special expertise (some of these were supplies for General Motors business abroad, i.e., artificial leather for car seats and finishes for car exteriors). In the United States and abroad, Du Pont was not involved in petrochemicals, but it kept well informed on everything about I.G. Farben s relationships with Standard Oil of New Jersey and with Shell. 

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