not Water paints are subdivided into oil and varnish paints (enamel) according to the basic binding substance of a paint. The core binding oil paints are vegetative and animal fats which in the processed kind name drying oils and oksoljami. Varnishes name solutions of various natural and synthetic pitches in organic solvents. Actually the majority of binding substances contains components and drying oils, and a varnish, and division of paints on oil and enamel is conditional enough. .
Drying oils are subdivided on structure on natural, combined or seminatural and synthetic.
Natural drying oils receive at cooking of vegetable oils (from seeds of flax, a hemp etc.) with sikkativom. Depending on a way of preparation receive or oxidised or polimerizovannuju drying oil. The maintenance of vegetable oils in natural drying oils should be not less than 95%.
Films from natural drying oils harden under the influence of two interconnected processes: oxidations and polymerisations, i.e. Consolidations (association) of molecules. Drying comes to an end within 24-30 hours and as a result these processes the firm substance - linoksin which is not dissolved in organic liquids is formed. Drying oil drying is slowed down in the dark and at the raised humidity and accelerated to 20 times at heats. At ageing elasticity of a film decreases and there are cracks. .
The Combined (seminatural) drying oils receive a condensation of vegetable oils (oksipolimerizatsija) and the subsequent them razbavleniem in solvents. It gives notable economy of oils (to 45%). Seminatural drying oil hardens owing to the further oxidation and solvent evaporation, and the formed film is more thin and is less steady, than at natural drying oil. Most widespread of seminatural drying oils is oksol which contains 45% solventa or varnish gasoline. In practice the combined drying oils can be distinguished on a strong smell of solvent; at all seminatural drying oils a smell of turpentine, kerosene or other similar liquid. The combined drying oils are suitable at internal works for a first coat, preparation shpaklevki and razbavlenija pastes of oil paints. .
Synthetic drying oils prepare from oil, slate oils, from natural oils and pitches with solvents. Their nomenclature is great, properties, in general, worse, than at natural drying oils: they are more dark, dry up more slowly, differ small moisture resistance and a weak film. At internal works use for razbavlenija dark paints and a spadework. They do not suit a floor.
Among synthetic drying oils as an exception are considered pentaftalevye and gliftalevye which receive as products of joint processing of corresponding pitches and natural drying oils. They are stronger some natural drying oils. All paints prepared on the basis of drying oil, are called as oil and are marked by letter MA (oil). .
Varnishes are solutions of natural and synthetic pitches or polymers in various organic solvents. In binding substances of varnishes of pitch are often processed together with drying oil, i.e. With the vegetable oils which maintenance in a varnish reaches 35%. Colour of the majority of varnishes - light, transparent. The exception is made by the varnishes made of bitumen and asphalt. They of black or black-brown colour.
From natural pitches of the most known it is considered rosin which receive from pitches of coniferous trees and use as binding in oil varnishes. From other natural pitches, such as shellac, dammar, dug, akaroid produce high-quality varnishes for the oil paints used in painting, and also polish.
Synthetic pitches form a basis for many varnishes and enamels. Thus varnishes and enamels of one subgroup have the identical alphabetic index designating binding substance. The short characteristic of varnishes and the enamels used in civil work (and in general distinguish more than forty special varnishes and enamels) is more low given.
Pentaftalevye varnishes and enamels PF are products of processing pentaftalevyh pitches, vegetable oils and rosin. A protective film - shining, elastic, weatherproof. Drying term at a room temperature till 24 o'clock. Dissolve gasoline, turpentine, solventom.
Gliftalevye varnishes and enamels TF are products of processing of corresponding pitches with vegetable oils and natural pitches. On chemical and technological properties gliftalevye binding are similar with pentaftalevymi. Both those and others belong to alkidnoj to group of binding substances. Mechanical properties gliftalevyh materials more low, than pentaftalevyh and them use only for internal works; by manufacture of their external works it is possible to apply as a soil paint. .
Nitrocellulose varnishes and enamels NTS is a numerous kind of the paints made of nitrocellulose. They are characterised by very fast drying, stability to weather conditions, a firm, strong film. A lack is inflammability and the small maintenance napolnitelja, in a paint. To receive a colour protective film of a necessary thickness, it is necessary to cover a surface to 6 times. The high-quality surface turns out at razbryzgivanii paints a spray.
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