Abstract: The invention provides a liquid crystal polyester resin which not only has a low-dielectric tangent, but also is excellent in balance between heat resistance and processing stability. The liquid crystal polyester resin comprises: a structural unit (I) derived from an aromatic hydroxycarboxylic acid; a structural unit (II) derived from an aromatic diol compound; and a structural unit (III) derived from an aromatic dicarboxylic acid, wherein the structural unit (I) is a structural unit (IA) derived from 6-hydroxy-2-naphthoic acid, the structural unit (III) contains a structural unit (IIIA) derived from terephthalic acid, a structural unit (IIIB) derived from isophthalic acid, and a structural unit (IIIC) derived from 2,6-naphthalenedicarboxylic acid, the dielectric tangent at a measurement frequency of 10 GHz is 1.50×10?3 or less, the melting point is 290° C. or more, and the difference in temperature between the melting point and the crystallization point is 30° C. or more.

Abstract: The invention provides a liquid crystal polyester resin which not only has a low-dielectric tangent, but also is excellent in balance between heat resistance and processing stability. The liquid crystal polyester resin comprises: a structural unit (I) derived from an aromatic hydroxycarboxylic acid; a structural unit (II) derived from an aromatic diol compound; and a structural unit (III) derived from an aromatic dicarboxylic acid, wherein the structural unit (I) contains a structural unit (IA) derived from 6-hydroxy-2-naphthoic acid, the structural unit (III) contains a structural unit (IIIA) derived from terephthalic acid, and a structural unit (IIIB) derived from isophthalic acid, the dielectric tangent at a measurement frequency of 10 GHz is 1.50×10?3 or less, the melting point is 295° C. or more, and the difference between the melting point and the crystallization point is 35° C. or more.

Abstract: The invention provides a liquid crystal polyester resin which not only has a low-dielectric tangent, but also is excellent in balance between heat resistance and processing stability. The liquid crystal polyester resin comprises: a structural unit (I) derived from an aromatic hydroxycarboxylic acid; a structural unit (II) derived from an aromatic diol compound; and a structural unit (III) derived from an aromatic dicarboxylic acid, wherein the structural unit (I) contains a structural unit (IA) derived from 6-hydroxy-2-naphthoic acid, the structural unit (III) contains a structural unit (IIIA) derived from isophthalic acid and a structural unit (IIIB) derived from 2,6-naphthalenedicarboxylic acid, the dielectric tangent at a measurement frequency of 10 GHz is 1.50×10?3 or less, the melting point is 290° C. or more, and the difference in temperature between the melting point and the crystallization point is 30° C. or more.