| abstract |
An improved electrical insulating oil which is stable in refining treatment and good electrical properties are maintained under high temperature conditions, and oil-filled electrical appliances impregnated therewith. The electrical insulating oil comprises 1,1,-diarylalkenes which are represented by the following general formula (I): <IMAGE> (I) wherein R1 to R4's are the same or different and each of them is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and m and n are integers from 0 to 3, inclusive. |