Patent ID: 7087358

Claim:
An infrared absorber comprising, in a molecule thereof, a fluorine-containing substituent which has at least 5 fluorine atoms, wherein said infrared absorber is represented by general formula (1) as follows: in which formula: each of R F 1 and R F 2 independently represents a fluorine-containing substituent having at least 5 fluorine atoms; each of X 1 and X 2 independently represents —CR 9 R 10 —, —S—, —Se—, —NR 11 —, —CH═CH— or —O—; R 1 to R 8 each independently represents a hydrogen atom, alkyl group, alkoxy group or halogen atom; R 1 to R 8 may represent a plurality of atoms such that at least one of pairs R 1 and R 3 , R 2 and R 4 , R 5 and R 7 , R 6 and R 8 , R 1 and X 1 , and R 2 and X 2 can be mutually connectable to form an aliphatic 5-membered ring or 6-membered ring, an aromatic 6-membered ring or a substituted aromatic 6-membered ring; R 9 and R 10 each independently represents an alkyl group, or represent ═CH— which are combined to form a ring; R 11 represents an alkyl group; Z 1 represents a heptamethine group, which may have one or more substituents selected from the group consisting of alkyl groups, halogen atoms, amino groups, arylthio groups, alkylthio groups, aryloxy groups, alkoxy groups, barbituric groups and thiobarbituric groups, and which may include a cyclohexene or cyclopentene ring formed by mutually bonding substituents on two methine carbons of the heptamethine group, which ring may further have a substituent selected from the group consisting of alkyl groups and halogen atoms; and X − represents a counter ion required for neutralizing an electric charge.