. . "bstituent which is employed together with the monomer (A) according to the present invention is a monomer represented by the following formula (I): ##STR6##wherein E.sup.1 represents an aliphatic group having 8 or more carbon atoms or a substituent having a total number of atoms of 8 or more, provided that hydrogen atoms directly attached to a carbon or nitrogen atom are excluded from the number,r" . .