1 results about "3-Hydroxybenzoic acid" patented technology

The objective of this invention is to provide a liquid crystal polyester resin that exhibits low dielectric constant and low dielectric loss tangent while simultaneously improving practical heat resistance and suppressing the generation of escape gases or foreign matter. The liquid crystal polyester resin based on this invention is characterized by comprising at least 90 mol% of constituent units derived from hydroxycarboxylic acids, including constituent units (A) derived from p-hydroxybenzoic acid, constituent units (B) derived from 6-hydroxy-2-naphthoic acid, and constituent units (C) derived from hydroxycarboxylic acids other than those described above (A) and (B). Constituent unit (C) is a constituent unit selected from at least one of m-hydroxybenzoic acid, 6-hydroxynicotinic acid, and 4'-hydroxy-4-biphenylcarboxylic acid. The liquid crystal polyester resin further… The step comprises at least one of a constituent unit (D) from a dicarboxylic acid and a constituent unit (E) from a diol, wherein the composition ratio (mol%) of the constituent units (A) to (E) satisfies the following conditions: 10 mol% ≤ constituent unit (A) ≤ 30 mol%, 60 mol% ≤ constituent unit (B) ≤ 80 mol%, 0.1 mol% ≤ constituent unit (C) ≤ 10 mol%, 0.1 mol% ≤ constituent unit (D) + constituent unit (E) ≤ 2.0 mol%, and the melt viscosity of the liquid crystal polyester resin measured at 350°C under a shear rate of 1000 / s is 25 Pa·s or higher.