Patent GB-445060-A (GB)
Title: Improvements relating to the insulation of electrical conductors
IPC: H01B3/28
Filed: 1935-03-01
Abstract: Electrical conductors are coated with insulating masses and lacquers comprising halogenized caoutchouc particularly chlorinated caoutchouc together with cellulose ethers, the components being brought into a plastic state or into solution by means of a common solvent or solvent mixture.  The preferred cellulose ethers are ethyl, methyl or benzyl cellulose.  The compositions may also contain softening agents such as phthalic acid esters, phosphoric acid esters of the phenols and their homologues such as tricresyl phosphate sulphonamides &c., mineral oil, linseed oil, wood oil, blown castor oil, bituminous substances, hardening agents such as natural or artificial resins, including phenol and phthalic acid resins, vinyl and "Glyptal" (Registered Trade Mark) resins, cyclohexanone and formaldehyde or phenol resins, and chlorinated diphenyls.  Age resisters such as aldol naphthylamine and fillers such as pigments may also be incorporated.  The solvent used may be such as to dissolve both components or may be a mixture of solvents for each component. Solvents specified include chloroform, benzene, carbon tetrachloride, acetic esters, e.g. butyl acetate, acetone, alcohol and xylol.  The components are preferably dissolved separately. The compositions may be pressed or coiled on to wires either bare or covered with fibrous material, or applied in the form of foils, bands, strips, cords or webs or applied as a pasty composition or lacquer.  In an example, a lacquer contains the following ingredients in parts by weight, benzyl cellulose 10, chlorinated caoutchouc 10, tricresyl phosphate 6,5, acetic ether 40, spirit 8, methyl acetate 6, benzene 19,5.  The Specification as open to inspection under Sect. 91 comprises also the use of caoutchouc derivatives containing other acid residues (e.g. sulphonated or acetylated caoutchouc) and of cellulose esters.  This subject-matter does not appear in the Specification as accepted.ALSO:Electrical conductors are coated with insulating masses and lacquers comprising halogenized caoutchouc particularly chlorinated caoutchouc together with cellulose ethers, the components being brought into a plastic state or into solution by means of a common solvent or solvent mixture.  The preferred cellulose ethers are ethyl, methyl or benzyl cellulose.  The compositions may also contain softening agents such as phthalic acid esters, phosphoric acid esters of the phenols and their homologues such as tricresyl phosphate, sulphonamides, &c., mineral oil, linseed oil, wood oil, blown castor oil, bituminous substances, hardening agents such as natural or artificial resins, including phenol and phthalic acid resins, vinyl and "Glyptal" (Registered Trade Mark) resins, cyclohexanone and formaldehyde or phenol resins, and chlorinated diphenyls.  Age resisters such as aldol naphthylamine and fillers such as pigments may also be incorporated.  The solvent used may be such as to dissolve both components or may be a mixture of solvents for each component.  Solvents specified include chloroform, benzene, carbon tetrachloride, acetic esters, e.g. butyl acetate, acetone, alcohol and xylol.  The components are preferably dissolved separately.  The compositions may be pressed or coiled on to wires either bare or covered with fibrous material, or applied in the form of foils, bands, strips, cords or webs or applied as a pasty composition or lacquer.  In an example, a lacquer contains the following ingredients in parts by weight, benzyl cellulose 10, chlorinated caoutchouc 10, tricresyl phosphate 6,5, acetic ether 40, spirit 8, methyl acetate 6, benzene 19,5.  The Specification as open to inspection under Sect. 91 comprises also the use of caoutchouc derivatives containing other acid residues (e.g. sulphonated or acetylated caoutchouc) and of cellulose esters.  This subject-matter does not appear in the Specification as accepted.