Patent ID: 6391228
Filing Date: 2002-05-21
Classification: H01B

Abstract:
Dielectric composition for electrical devices, comprising from 99% to 70% by weight of a mineral oil and from 1% to 30% by weight of at least one polyarylalkane composition chosen from:the compositions (I) comprising a mixture of products of formula (A): in which formula n1 and n2=0 or 1, which comprises products (A) such that n1+n2=0 and products (A) such that n1+n2=1, and of products of formula (B): the compositions (II) comprising a mixture of two products (C) and (D), in which mixture: the product (C) is a mixture of isomers of formula: with p1 and p2=0, 1 and 2, and p1+p2&lE;3, and the product (D) is a mixture of isomers of formula: with pâ€²1, pâ€³1 and p4=0, 1 and 2 pâ€²2, pâ€³2, p3 and p5=0 and 1 it being known that pâ€²1+pâ€³1+pâ€²2+pâ€³2+p3+pâ€²3 +p4+p5&lE;2, the compositions (III) comprising a mixture of two products (A1) and (A2), such that: the product (A1) is a mixture of isomers of formula: with m1 and m2=0, 1 or 2, it being known that m1+m2&lE;3, the product (A2) is a mixture of isomers of formula: with q1 and q2=0, 1 or 2, it being known that q1+q2&lE;3, at least one of the compounds (A1) and (A2) comprising an isomer having three benzene nuclei, the compositions (IV) comprising the two products (A1) and (A2) and, in addition, at least one compound chosen from the following products (E1), (E2) or (E3); (E1) is an isomer or a mixture of isomers of formula: with râ€²1, râ€³1 and r4=0, 1 or 2 râ€²2, râ€³2, r3, râ€²3 and r5=0 and 1 it being known that râ€²1+râ€³1+râ€²2+râ€³2+r3+râ€²3+r4+r5 is less than or equal to 2, R1 and R2 represent a hydrogen atom, (E2) is an isomer or a mixture of isomers with the same general formula as (E1), except that R1 and R2 represent a methyl and the coefficients r are replaced by s and have the same meaning, (E3) is an isomer or a mixture of isomers with the same general formula as (E1), except that R1 and R2 are different and represent a hydrogen atom or a methyl radical and the coefficients r are replaced by t and have the same meaning.