1-2 BASIC KNOWLEDGE ABOUT PAINTS AND PAINTING 1 DEFINITION AND PURPOSES OF PAINTING 1. DEFINITION Painting is a process in which a liquid called "paint" is applied to form a thin film which, when dried and hardened, turns into a very hard coat. DEFINITION OF PAINTING 2. PURPOSES OF PAINTING ( 1) Protection Automobiles, ships, bridges, etc., are main- ly made of iron, a material that tends to rust easily when exposed to air. When rust develops on iron, those structures lose their original physical strength or shape. Rust can be prevented, however, by paint- ing the iron so that the original perfor- mance of the structures can be maintained over a longer period of time.
Painting may be applied also to lumber. Wood can be protected from such defects as surface scratching, decay and worms if they are coated with a paint that contains rust pre- ventive and insecticide. In summary, the major purpose of painting is to protect the object from external ele- ments of damage. PROTECTION FROM DAMAGE (2) Cosmetic improvement Painting gives colors and luster to vehicles and enhances their cosmetic appearance. They look better, and their commercial value increases, if they are painted well. Bumpers may be painted in the same color as the body itself and door sashes may be painted black to improve the quality of the vehicle. These are also important purposes of painting.
(3) Identification by painting Fire engines and police cars are often painted red. Painting is also used to differentiate certain vehicles from all others. COSMETIC IMPROVEMENT -4-