By treating a material to be treated with a multifunctional surface-treatment agent composition containing octadecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride and/or octadecyldimethyl(3-triethoxysilylpropyl)ammonium chloride, an amido amine oxide, an alcohol, and water, cloudiness and precipitation occurring during low-temperature storage is prevented antibacterial properties are exhibited deodorization properties, water repellency, and oil repellency are improved and frictional resistance is reduced.옥타데실디메틸(3-트리메톡시실릴프로필)암모늄 클로라이드 및/또는 옥타데실디메틸(3-트리에톡시실릴프로필)암모늄 클로라이드와, 아미도아민옥시드류, 및 알코올과 물을 함유하는 표면 다기능 처리제 조성물에 의해 피처리물을 처리함으로써, 저온하에서 보존하면 백탁이나 침전의 발생을 방지하여, 항균성을 발휘시키는 동시에, 방취, 발수, 발유성을 향상시키고, 또한 마찰저항을 저감시킨다.
