Light-resistant, heat-resistant and durable ultraviolet absorber

An ultraviolet absorber used in an ultraviolet shielding film for glass or in a composition for forming an ultraviolet shielding film for glass, comprising a 2-phenylbenzotriazole derivative that contains a thioaryl ring group, thiocyclohexyl ring group, thioalkyl group or thioalkylene group and is represented by any one of the following formulae (1) to (6):

• wherein PhBzT1a represents a substituted or unsubstituted 2-phenylbenzotriazole skeleton bonded to a thioaryl ring group (—S—X1a— . . . ), X1a represents a residue of a phenyl or naphthyl ring, X1a may have a substituent group(s) other than l R1as, each of the l R1as independently represents a hydrocarbon group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a hydroxy group, the hydrocarbon group and alkoxy group represented by R1a may each have hydrogen atoms of carbon chains therein substituted by, base ends of the carbon chains therein interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom, l represents an integer of 0 to 5;
• wherein PhBzT1b represents a substituted or unsubstituted 2-phenylbenzotriazole skeleton bonded to a thiocyclohexyl ring group (—S-Cy- . . . ), Cy represents a cyclohexyl ring residue, Cy may have a substituent group(s) other than m R1bs, each of the m R1bs independently represents a hydrocarbon group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a hydroxy group, the hydrocarbon group and alkoxy group represented by R1b may each have hydrogen atoms of carbon chains therein substituted by, base ends of the carbon chains therein interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom, m represents an integer of 0 to 5;
• wherein each of PhBzT1c and PhBzT2c independently represents a substituted or unsubstituted 2-phenylbenzotriazole skeleton bonded to a thioaryl ring group or thioalkylene group (—S-A1c-S—), A1c represents a group expressed by the following formula, a phenyl ring residue, a naphthyl ring residue or a linear or branched alkylene group that has 1 to 22 carbon atoms and may have hydrogen atoms therein substituted by, at least one of two ends thereof interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom,
• wherein each of X1c and X2c independently represents a residue of a phenyl or naphthyl ring, X1c and X2c may have substituent groups other than n R1cs and p R2cs, each of the n R1cs and p R2cs independently represents a hydrocarbon group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a hydroxy group, the hydrocarbon groups and alkoxy groups represented by R1c and R2c may each have hydrogen atoms of carbon chains therein substituted by, base ends of the carbon chains therein interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom, each of n and p represents an integer of 0 to 4, A2c represents a divalent hydrocarbon group that has 1 to 20 carbon atoms and may have hydrogen atoms therein substituted by, at least one of two ends thereof interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom, a divalent aromatic group or a sulfide group —S—, q represents an integer of 0 or 1;
• wherein each of PhBzT1d and PhBzT2d independently represents a substituted or unsubstituted 2-phenylbenzotriazole skeleton that has a thioaryl ring group (—S—X1d— . . . or —S—X2d— . . . ) bonded to a phenyl moiety of a benzotriazole skeleton and A1d bonded to a position-2 phenyl skeleton Ph, each of X1d and X2d independently represents a residue of a phenyl or naphthyl ring, X1d and X2d may have substituent groups other than r R1ds and s R2ds, each of the r R1ds and s R2ds independently represents a hydrocarbon group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a hydroxy group, the hydrocarbon groups and alkoxy groups represented by R1d and R2d may each have hydrogen atoms of carbon chains therein substituted by, base ends of the carbon chains therein interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom, each of r and s represents an integer of 0 to 5, A1d represents a divalent hydrocarbon group that has 1 to 20 carbon atoms and may have hydrogen atoms therein substituted by, at least one of two ends thereof interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom;
• wherein PhBzT1e represents a substituted or unsubstituted 2-phenylbenzotriazole skeleton bonded to a thioalkyl group (—S—Y1e), Y1e represents a linear or branched alkyl group that has 1 to 22 carbon atoms and may have hydrogen atoms therein substituted by, base ends thereof interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom;
• wherein each of PhBzT1f and PhBzT2f independently represents a substituted or unsubstituted 2-phenylbenzotriazole skeleton that has a thioalkyl group (—S—Y1f or —S—Y2f) bonded to a phenyl moiety of a benzotriazole skeleton and A1f bonded to a position-2 phenyl skeleton Ph, each of Y1f and Y2f independently represents a linear or branched alkyl group that has 1 to 22 carbon atoms and may have hydrogen atoms therein substituted by, base ends thereof interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom, A1f represents a divalent hydrocarbon group that has 1 to 20 carbon atoms and may have hydrogen atoms therein substituted by, at least one of two ends thereof interrupted by, or carbon-carbon bonds therein interrupted by a monovalent or divalent group(s) selected from an aromatic group, an unsaturated group, a nitrogen-containing group, a sulfur-containing group, an oxygen-containing group, a phosphorus-containing group, an alicyclic group and a halogen atom.