The present invention addresses the problem of providing a novel additive for surface activation and an emulsion composition using same, in which an excellent emulsion stability is obtained. The present invention also addresses the problem of improving the usage feel in a cosmetic and the lubrication performance in a lubricant. This additive for surface activation is one in which the following components (A) and (B) are compounded. (A) An amine or ammonium compound having a hydroxyaliphatic hydrocarbon group that contains one or more hydroxy groups and optionally contains an oxygen atom unassociated with the hydroxy groups; and (B) an unsaturated or branched aliphatic acid having 8 to 22 carbon atoms or a salt thereof. In addition, this emulsion composition is one in which the above additive has been added.

The present invention addresses the problem of providing a novel additive for surface activation and an emulsion composition using same, in which an excellent emulsion stability is obtained. The present invention also addresses the problem of improving the usage feel in a cosmetic and the lubrication performance in a lubricant. This additive for surface activation is one in which the following components (A) and (B) are compounded. (A) An amine or ammonium compound having a hydroxyaliphatic hydrocarbon group that contains one or more hydroxy groups and optionally contains an oxygen atom unassociated with the hydroxy groups; and (B) an unsaturated or branched aliphatic acid having 8 to 22 carbon atoms or a salt thereof. In addition, this emulsion composition is one in which the above additive has been added.

A lubricating oil composition for refrigerating machines contains a base oil and an additive in a form of a coumarin compound. When the present lubricating oil composition for refrigerating machines is used in refrigerating equipment such as an open-type automobile air-conditioner, an electric automobile air-conditioner, a gas heat pump, other air-conditioning equipment, a refrigerating machine, a vending machine, a showcase, a water-heating system and a refrigerating/heating system, it is possible to detect the leakage of a refrigerant with a long-lasting stability. Therefore, when an unsaturated chlorofluorocarbon refrigerant with a poor stability is used in the above-listed equipment, the present lubricating oil composition for refrigerating machines is significantly advantageous.

A lubricating oil composition for refrigerating machines contains a base oil and an additive in a form of a coumarin compound. When the present lubricating oil composition for refrigerating machines is used in refrigerating equipment such as an open-type automobile air-conditioner, an electric automobile air-conditioner, a gas heat pump, other air-conditioning equipment, a refrigerating machine, a vending machine, a showcase, a water-heating system and a refrigerating/heating system, it is possible to detect the leakage of a refrigerant with a long-lasting stability. Therefore, when an unsaturated chlorofluorocarbon refrigerant with a poor stability is used in the above-listed equipment, the present lubricating oil composition for refrigerating machines is significantly advantageous.