Uses
A lacquer is a solution of a hard linear polymer in an organic solvent.
It dries by simple evaporation of the solvent. The film-forming polymers usually used are chlorinated rubber, nitro cellulose, acrylics, vinyl resins,
or other high molecular weight linear polymers. The properties of lacquers
vary with the main type of film-forming resin used, and their
main advantage is rapid drying speed. They are made for application
to a wide variety of substrates at all practical temperatures and particularly
where oven heating is not available.
Industrial uses
The word lacquer comes from lac resin, which is the base of common shellac. Lac resin dissolved in alcohol was one of the first lacquers and has been in use for many centuries. Nowadays, shellac is called spirit lacquer. It is only one of several different kinds of lacquers; these, except for spirit lacquer, are named after the chief film-forming ingredient. The most common ones are cellulose acetate, cellulose acetate butyrate, ethyl cellulose, vinyl, and nitrocellulose. A distinguishing characteristic of lacquers is that they dry by evaporation of the solvents or thinners in which the vehicle is dissolved. This is in contrast to oils, varnishes, or resin base finishes, which are converted to a hard film chiefly through oxidation or polymerization. Lacquers can be either clear and transparent or pigmented, and their color range is practi-cally unlimited.
