Abstract: A lubricating oil for compression-type refrigerators which comprises as the main component thereof a polyvinyl ether compound having excellent compatibility with a hydrofluorocarbon or a hydrochlorofluorocarbon, such as 1,1,1,2-tetrafluoroethane and the like, which can be used as the refrigerant to replace compounds causing environmental pollution, such as dichlorofluoroethane and the like, and having an excellent lubricating property is disclosed. The lubricating oil for compression-type refrigerators comprises as the main component thereof a polyvinyl ether compound having the constituting units expressed by the general formula: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 are H or a hydrocarbon group of C.sub.1.about.8, R.sup.4 is a bivalent hydrocarbon group of C.sub.2.about.10, R.sup.5 is a hydrocarbon group of C.sub.1.about.10 and m is 0.about.10.

Abstract: A method of production of an ether compound from an acetal compound or a ketal compound which is excellent in conversion and selectivity and does not cause corrosion of apparatuses and a novel useful polyvinyl ether compound as lubricating oil for compression-type refrigerators, electric insulation oil and the like are disclosed. The method of production of the present invention comprises reaction of an acetal compound or a ketal compound with hydrogen in the presence of a solid catalyst having acidic property and hydrogenation ability to produce the corresponding ether compound. The polyvinyl ether compound of the present invention comprises the constituting unit expressed by the general formula: ##STR1## (characters in the general formula are the same as those described in the specification), contains none of unsaturated bond, acetal structure and aldehyde structure in the molecule and has weight average molecular weight in the range of 300 to 3000.