The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California
House Painting
Materials
PAINT is composed of two parts: a liquid, which is mainly oil in most house-paints, and a powdered solid, which gives color and body to the mixture. The liquid part is especially termed the vehicle; the solid, the pigment. The oil is linseed oil, made from flax-seed; raw oil is the natural oil, which will dry or become hard enough to handle, if exposed to the air in a thin film, in about a week; and boiled oil is the same, to which has been added a small pro-portion of "drier," and will dry in twelve to twenty-four hours. Paint drier, also known as japan, or paint japan, is a compound of lead, or manganese, or both, soluble in oil; it takes up oxygen from the air, and passes it over to the oil; for it must be known that oil dries, not at all by evaporation, but by absorbing oxygen from the air anduniting chemically with it, so as to make a new material, which is not a liquid, but is a tough, leathery solid, and weighs a fifth or a quarter more than the oil from which it was made. This is technically called linoxyn.
The drier is, therefore, a chemical agent, and acts toward oil somewhat as kindling-wood does to coal, only it doesn't entirely burn up, but keeps on acting for a long time. If too much of it is used the oxidation, or combustion, goes on too strongly, and the oil gets over-oxidized, or burned, and its tough-ness and elasticity are impaired; therefore we must be sparing in its use, for we find the slow-drying paints are the most durable. Paint drier is usually sold as a liquid, and to a gallon of oil in paint not more than five or ten per cent of drier should be added; less for outside than for inside paints. The best driers do not contain rosin, but most cheap driers do. It is not often necessary to use drier with boiled oil, as the manufacturer has already put in as much drier as is desirable. Drier should never be added to mixed paint, as the maker has exactly proportioned the ingredients to give the best results; there are cases where it is proper to add oil to a mixed paint, and sometimes turpentine, but not drier.
Turpentine is sometimes an ingredient of paint. In this connection it always means the essential oil of turpentine, a colorless liquid, lighter than water, highly inflammable, volatile. It mixes perfectly with oil, and increases the fluidity of paint. If we mix a considerable amount of it with paint, it makes a thinner film and one which is not glossy when dry, but dull, — what painters call "flat."
