Coating agent

A coating solution comprising:

• a compound represented by formula (I):
• wherein
• A represents
• wherein R1 represents an electron-donating group, a represents an integer of 0 to 5, and a′ represents an integer of 0 to 7,
• Z represents a carbon atom or a silicon atom,
• R2 represents a hydrogen atom, a hydroxyl group, a linear or branched C1 to C6 alkyl group, a linear or branched C1 to C6 alkoxy group, a C3 to C6 cyclic alkyl group, or a C3 to C6 cyclic alkoxy group,
• X represents, when Z is a carbon atom,
• (i) a C1 to C20 alkylene group optionally comprising an oxygen atom, a sulfur atom, a selenium atom, a C3 to C6 divalent aliphatic ring group, a C6 to C10 arylene group, an amide structure, a urethane structure, or —NR— wherein R represents a hydrogen atom or a C1 to C6 alkyl group;
• (ii) one of the following groups:
• wherein m1 represents an integer of 0 or 1, n1 represents an integer of 1 to 20, n2 represents an integer of 1 to 10, n3 and n4 each independently represent an integer of 1 to 10, and R represents a hydrogen atom or a C1 to C6 alkyl group;
• (iii) a C3 to C10 divalent aliphatic ring group;
• or
• (iv) a C6 to C10 arylene group;
• and when Z is a silicon atom,
• a C1 to C20 alkylene group comprising a sulfur atom, a selenium atom, an amide structure, a urethane structure, or —NR— wherein R represents a hydrogen atom or a C1 to C6 alkyl group;
• Y represents —O—CO—(O)m2—CR═CH2 with m2 representing 0 or 1 and R representing a hydrogen atom or a methyl group;
• —CH═CH2;
• an allyloxy group;
• an allyloxycarbonyloxy group;
• an epoxy group;
• n represents an integer of 2 or 3,
• m represents an integer of 1 or 2,
• l represents an integer of 0 or 1, and n+m+l=4;
• and
• when n represents an integer of 2 or 3, A is the same or different;
• and
• an organic solvent,
• wherein:
• a total amount of all solids in the coating solution is in the range of 1 to 90% by mass, and
• the compound represented by formula (I) constitutes 30 mol % or more of all polymerizable compounds in the coating solution.