Photocurable resin composition

1. A photocurable resin composition comprising:

a polymer with a weight average molecular weight of 1,000 to 50,000, the polymer having a structural unit of formula (1), and having a terminal end-group structure of formula (2):

wherein

X is a methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, s-butyl group, t-butyl group, n-pentyl group, 1-methyl-n-butyl group, 2-methyl-n-butyl group, 3-methyl-n-butyl group, 1,1-dimethyl-n-propyl group, 1,2-dimethyl-n-propyl group, 2,2-dimethyl-n-propyl group, 1-ethyl-n-propyl group, n-hexyl group, 1-methyl-n-pentyl group, 2-methyl-n-pentyl group, 3-methyl-n-pentyl group, 4-methyl-n-pentyl group, 1,1-dimethyl-n-butyl group, 1,2-dimethyl-n-butyl group, 1,3-dimethyl-n-butyl group, 2,2-dimethyl-n-butyl group, 2,3-dimethyl-n-butyl group, 3,3-dimethyl-n-butyl group, 1-ethyl-n-butyl group, 2-ethyl-n-butyl group, 1,1,2-trimethyl-n-propyl group, 1,2,2-trimethyl-n-propyl group, 1-ethyl-1-methyl-n-propyl group, 1-ethyl-2-methyl-n-propyl group, —CH═CH 2 , —CH 2 —CH═CH 2 , or

m and n are each independently 0 or 1;

Q is a divalent hydrocarbon group having a carbon atom number of 1 to 16;

Z is a divalent linking group having a carbon atom number of 1 to 4, wherein the divalent linking group is attached to the —O— group in formula (1); and

R 1 is a hydrogen atom or methyl group;

a radical photopolymerization initiator; and

a solvent.

2. The photocurable resin composition according to claim 1 , wherein the divalent hydrocarbon group of Q in formula (1) is a linear or branched alkylene group, a group containing two carbon atoms connected by a double bond, or a group containing, in a main chain, an alicyclic hydrocarbon group or aromatic hydrocarbon group optionally having at least one substituent.

3. The photocurable resin composition according to claim 1 , wherein the divalent linking group of Z in formula (2) is a linear or branched alkylene group optionally having at least one hydroxy group as a substituent.

4. The photocurable resin composition according to claim 1 , further comprising a bifunctional (meth)acrylate and/or a polyfunctional thiol.

5. The photocurable resin composition according to claim 1 , which is for use as an adhesive or a lens material.

6. A method for forming a film comprising the steps of:

applying the photocurable resin composition according to claim 1 onto a substrate;

pre-baking the photocurable resin composition applied onto the substrate at a temperature of 50 to 160° C.;

exposing a coating film formed on the substrate after the pre-baking to light;

and developing the coating film.