Abstract: Disclosed is a photo-curable antifogging composition which may be applied to substrates such as glass, various plastic materials and the like to give antifogging property on the surface of these substrates. The main ingredient of the composition is a quaternary ammonium salt of the following formula (1): wherein: R1 is CH3(CH2)nCH2 or CH3(CH2)nCH2C6H4 wherein n is an integer from 1 to 16 inclusive; R2 and R3 are the same or different from each other, and represent CH2═C(CH3)COOCH2CH(OH)CH2,CH2═CHCOOCH2CH(OH)CH2 or H, with the proviso that R2 and R3 may not be H at the same time; R4 is H, CH3, CH3CH2 or CH3CH2CH2; and X is CH3OSO3, CH3CH2OSO3, CH3COO, CF3COO, CH3(CH2)nCOO wherein n is an integer from 1 to 16 inclusive, CH3(CH2)7CH═CH(CH2)7COO, C6H5COO, C6H5CH(OH)COO, HOOCCH2CH(OH)COO, Cl or Br.

Abstract: Disclosed is a photo-curable antifogging composition which may be applied to substrates such as glass, various plastic materials and the like to give antifogging property on the surface of these substrates. The main ingredient of the composition is a quaternary ammonium salt of the following formula (1): wherein:R.sup.1 is CH.sub.3 (CH.sub.2).sub.n CH.sub.2 or CH.sub.3 (CH.sub.2).sub.n CH.sub.2 C.sub.6 H.sub.4 wherein n is an integer from 1 to 16 inclusive;R.sup.2 and R.sup.3 are the same or different from each other, and represent CH.sub.2 .dbd.C(CH.sub.3)COOCH.sub.2 CH(OH)CH.sub.2, CH.sub.2 .dbd.CHCOOCH.sub.2 CH(OH)CH.sub.2 or H, with the proviso that R.sup.2 and R.sup.3 may not be H at the same time;R.sup.4 is H, CH.sub.3, CH.sub.3 CH.sub.2 or CH.sub.3 CH.sub.2 CH.sub.2 ; andX is CH.sub.3 OSO.sub.3, CH.sub.3 CH.sub.2 OSO.sub.3, CH.sub.3 COO, CF.sub.3 COO, CH.sub.3 (CH.sub.2).sub.n COO wherein n is an integer from 1 to 16 inclusive, CH.sub.3 (CH.sub.2).sub.7 CH.dbd.CH(CH.sub.2).sub.7 COO, C.sub.6 H.sub.