A clear solution of nitrocellulose in an organic solvent, usually acetone, ethyl acetate or diethyl ether (collodion), used to coat metal products, documents, etc. to protect them from aggressive environments, as well as for labeling. After drying, it forms a strong, gas and waterproof film.
To add color, organic dyes are added to the varnish.
The main application of zaponlak in electronics is the coating of electrical connections soldered with tin-lead solders. The need for coverage is due to the fact that the main reason for the failure of equipment with hinged mounting of electronic elements over time - ring microcracks at the soldering point - by themselves are not capable of causing a breakdown in electrical contact and equipment failure, but penetration of water vapor into the crack with their subsequent condensation causes over time, the formation of films of poorly conducting electric current of tin and lead oxides, which increases the electrical resistance of the contact. Tsaponlak applied to the soldered joint forms a strong, elastic film on its surface, which prevents the development of corrosion in cracks. It also serves as a marker for visual control of the quality of soldering - the inspector marks the soldering he has checked. The zaponlac used for this is painted in a raspberry, green or dark purple color by adding synthetic organic dyes to the nitrocellulose solution.
Tsaponlak has a limited use in lighting engineering - it is used to paint the bulbs of low-power incandescent lamps, for example, in Christmas tree electric garlands.
Tsaponlak is used in the manufacture of Christmas trees and other decorations, in modeling, etc.
It is also used in technology for fixing (locking) threaded connections to protect against spontaneous loosening when exposed to vibrations.