Abstract: Provided is a curable composition that is soluble in various solvents (organic solvents other than highly toxic organic solvents, for example, cyclohexanone) while maintaining excellent low dielectric properties, wherein a film obtained by curing the curable composition has excellent mechanical properties. A curable composition, comprising: a polyphenylene ether having a functional group including an unsaturated carbon bond, which is obtained from raw material phenols including phenols satisfying at least condition 1 (having a hydrogen atom at an ortho position and a para position), and having a slope calculated by a conformation plot of less than 0.6; and at least one of a compound containing at least one maleimide group in one molecule, a triazine-based compound containing at least one thiol group, and crosslinked polystyrene particles.

Abstract: The present invention provides a poly(phenylene ether) which retains low-dielectric characteristics and is soluble in various solvents. The poly(phenylene ether) is characterized by being obtained from one or more raw-material phenols including a phenol satisfying at least Requirement 1 (to have hydrogen atoms in the ortho and para positions) and by having a slope calculated from a conformational plot of less than 0.6.