Manufacture of rubber having age-resisting properties

摘要

The ageing of rubber is retarded by the addition to the mix of a salt of a compound obtainable by interaction of boric acid and an a -dihydroxy compound such as catechol, 1 - methyl - 3 - 4 - dihydroxybenzene, and 2 : 3 - dihydroxynaphthalene. Salt forming components mentioned are zinc, sodium, potassium, barium, calcium, strontium, ammonium, butylamine, dibutylamine, tributylamine, piperidine, pyridine, a -methylpiperidine, aniline, methylamine, propylamine, isopropylamine, ethanolamine, methylaniline, dimethylaniline, 2-4-tolylenediamine, b -naphthylamine, diphenylguanidine, and di-o-tolyl-guanidine. The salts obtained do not discolour rubber when a mix containing them is exposed to bright sunlight, and are effective anti-agers when rubber mixes containing them are cured with sulphur chloride.