Stepped substrate-coating composition containing polyether resin having photocrosslinkable group

A photocurable composition for coating a stepped substrate, the photocurable composition containing a polymer containing a unit structure of Formula (1):

• [wherein A1, A2, and A3 are each independently an aromatic C6-100 ring optionally containing a heteroatom or a hydrocarbon group containing an aromatic C6-100 ring optionally containing a heteroatom, B1, B2, and B3 are each independently Formula (2):
• (wherein R1 is a C1-10 alkylene group, a C1-10 alkenylene group, a C1-10 alkynylene group, a C6-40 arylene group (the alkylene group, the alkenylene group, the alkynylene group, and the arylene group are optionally substituted with one or two or more cyano groups and/or one or two or more hydroxyl groups), an oxygen atom, a carbonyl group, a sulfur atom, —C(O)—O—, —C(O)—NRa—, —NRb—, or a group including a combination thereof, Ra is a hydrogen atom or a C1-10 alkyl group, Rb is a hydrogen atom, a C1-10 alkyl group, or a C2-10 alkylcarbonyl group, R2 is a hydrogen atom or a C1-10 alkyl group, and a dotted line is a bond with A1, A2, or A3), X is a carbonyl group, a sulfonyl group, a —CR22— group, or a —C(CF3)2—group, n1 is an integer of 1 or more and 4 or less, n2 is an integer of 0 or more and 4 or less, n3 is an integer of 0 or more and 4 or less, and n1+n2+n3 is an integer of 1 to 12].