GB552084A - Improvements in or relating to insulating electrical conductors - Google Patents

Abstract

552,084. Polyamides; phenol and polyhydricalcohol - - polybasic acid resins. DU PONT DE NEMOURS & CO., E. I. Sept. 19, 1941, No. 12108. Convention date, Oct. 18, 1940. [Class 2 (iii)] Compositions for making electrical insulating coatings, e.g. wire enamels, comprise a synthetic linear polyamide, as described in U.S.A. Specifications 2,071,250, 2,130,523, 2,130,948, a phenol - aldehyde resin and an alkyd resin 8 ; an oxidised drying oil may also be added. In examples wires are coated with the following compositions :-(1) polyhexamethylene adipamide 50 parts, alkyd resin 17 parts, phenol formaldehyde resin 33 parts, cresols 200 parts, high flash coaltar naphtha 200 parts, liquid lead-manganese drier 1 part; (3) polyhexamethylene adipamide 25 parts, alkyd resin 37.5 parts, phenol formaldehyde resin 37.5 parts, thiodiphenylamine 0.5 parts, cresols 100 parts, naphtha 100 parts, drier 2 parts. The alkyd resin may comprise glyceryl phthalate with linseed oil, china wood oil, perilla oil or rosin mixed in specific proportions. The Specification as open to inspection under Sect. 91, also described the following compositions :-(4) polyhexamethylene adipamide 25 parts, phenol formaldehyde resin 37.5 parts, air blown linseed oil 37.5 parts, cresols 100 parts, naphtha 100 parts, driers 2 parts; (5) polyhexamethylene adipamide 50 parts, alkyd resin 25 parts, rosin 25 parts, cresols 200 parts, naphtha 200 parts, drier 1 part. This subjectmatter does not appear in the Specification as accepted.