Explanatory notes
… dispersions of lac, natural gums or resins (shellac, copal, rosin, damar, etc.) in alcohol (spirit varnishes), gum, wood … on the addition of a hardener but on the effect of heat or atmospheric moisture; or (c) oligomers (i.e., polymers comprising 2, 3 or 4 monomer units) and cross-linking monomers, with or without photo-initiators. …