GB191218287A - A Process for the Manufacture of Insoluble Condensation Products. - Google Patents

Abstract

18,287. Pollak, F. Dec. 6, 1911, [Convention date]. Phenol-formaldehyde condensation products.- In the production of insoluble, air-proof, and odourless condensation products from phenols and formaldehyde, a soluble resin is first obtained from phenols and tri- or poly-oxymethylenes without using contact agents, and after purification by repeated washing with water and heating to over 105‹ C., formaldehyde solution is added, and the mixture is heated to 30-40‹ C. in vacuo until distillation ceases; the temperature is then raised to about 95‹ C. to drive off all water and traces of phenol, and the mass is finally hardened by heating in moulds. The tri- or poly-oxymethylenes employed in the initial process are those insoluble in sodium sulphite solution; instead of these bodies paraformaldehyde of high volatilisation-point may be employed in presence of very small quantities of acid. Small amounts of cresols, resorcin, chlorphenols, &c., may be added to the phenol used in the initial process. Instead of using formaldehyde solution in the vacuum distillation process, paraformaldehyde soluble in water may be used. Very small amounts of acids; bases, or salts may be added before or during the vacuum distillation. Filling or colouring materials may be added to the mass before the hardening process. The hardening process may be effected under pressure, or in an atmosphere of formaldehyde. Specification 1921/08 is referred to.