That is, a diacrylate compound or a dimethacrylate compound represented by the general formula (I) ##STR1## wherein R1 and R2 may be the same or different and are hydrogen atoms or methyl groups, and A is the same or different alkylene group, oxyalkylene group, or a group of the following formula which may be substituted, ##STR2## wherein R3 is a hydrogen atom or a methyl group, X is a halogen ato