Abstract: A cross-linked polymer including a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (1): wherein R1 represents an alkyl group having 1 to 5 carbons and n represents an integer from 1 to 5; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (2): wherein R2 represents a divalent saturated hydrocarbon group having 2 to 17 carbons, containing an aromatic ring; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and the polymers are cross-linked to each other.

Abstract: A cross-linked polymer including a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (1): wherein R1 represents an alkyl group having 1 to 5 carbons and n represents an integer from 1 to 5; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (2): wherein R2 represents a divalent saturated hydrocarbon group having 2 to 17 carbons, containing an aromatic ring; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and the polymers are cross-linked to each other.