Patent ID: 7892711

Claim:
An azo compound represented by a general formula (1): (wherein, R 1 and R 2 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; X 1 represents single bond when R 1 is a hydroxy group and represents a linking group represented by -(A 1 -B 1 ) m -when R 1 is a polymerizable functional group; X 2 represents a single bond when R 2 is a hydroxy group and represents a linking group represented by -(A 2 -B 2 ) n -when R 2 is a polymerizable functional group, wherein A 1 is bonded to R 1 , A 2 is bonded to R 2 , and B 1 and B 2 each is bonded to an adjacent phenylene group; A 1 and A 2 each independently represents a single bond, or a phenylene or arylene group which may have a linear alkylene group having 1 to 18 carbon atoms, a branched alkylene group having 1 to 18 carbon atoms, or a linear or branched alkoxy group having 1 to 18 carbon atoms; B 1 and B 2 each independently represents a single bond, —O—, —CO—O—, —O—CO—, —CO—NH—, —NH—CO—, —NH—CO—O—, or —O—CO—NH—; m and n each independently represents an integer of 0 to 4, provided that a plurality of A 1 (s), B 1 (s), A 2 (s) and B 2 (s) is the same or different when m or n is 2 or more, A 1 or A 2 interposed between two B 1 (s) or B 2 (s) is not a single bond, and a combination of A 1 and B 1 or a combination of A 2 and B 2 is not a combination of only a linear alkylene group and —O—; R 3 and R 4 each independently represents —OR 7 (wherein, R 7 represents an alkyl group having 2 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms substituted with a lower alkoxy group having 1 to 6 carbon atoms), a hydroxyalkyl group having 1 to 4 carbon atoms, or —CONR 8 R 9 (wherein, R 8 and R 9 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms); and R 5 and R 6 each independently represents a carboxy group, a sulfo group, a nitro group, amino group, or a hydroxy group, provided that a carboxy group and a sulfo group may be bonded to an alkali metal to form a salt).