An azo compound of the present invention is represented by the general formula (1): (wherein, R1 and R2 each independently represents a hydroxy group, or a polymerizable functional group selected from the group consisting of a (meth)acryloyl group, a (meth)acryloyloxy group, a (meth)acrylamide group, a vinyl group, a vinyloxy group, and a maleimide group; X1 represents single bond when R1 is a hydroxy group and represents a linking group represented by -(A1-B1)m- when R1 is a polymerizable functional group; X2 represents a single bond when R2 is a hydroxy group and represents a linking group represented by -(A2-B2)n- when R2 is a polymerizable functional group; R3 and R4 each independently represents —OR7, a hydroxyalkyl group having 1 to 4 carbon atoms, or —CONR8R9; and R5 and R6 each independently represents a carboxy group, a sulfo group, a nitro group, amino group, or a hydroxy group).