Patent ID: 7005497

Claim:
A liquid-crystalline polyester production method comprising one of the following steps (A) to (C): (A) acylation reaction of the phenolic hydroxyl group of an aromatic hydroxycarboxylic acid by using a fatty acid anhydride to obtain acylated aromatic hydroxycarboxylic acid, and successively ester-exchange reaction by reacting the acylated aromatic hydroxycarboxylic acid with each other; (B) acylation reaction of the phenolic hydroxyl group of an aromatic diol by using a fatty acid anhydride to obtain acylated aromatic diol, and successively ester-exchange reaction by reacting the acylated aromatic diol with an aromatic dicarboxylic acid; and (C) acylation reaction of the phenolic hydroxyl group of an aromatic diol and an aromatic hydroxycarboxylic acid by using a fatty acid anhydride to obtain acylated aromatic diol and acylated aromatic hydroxycarboxylic acid, and successively ester-exchange reaction by reacting the acylated aromatic diol and acylated aromatic hydroxycarboxylic acid with an aromatic dicarboxylic acid; wherein the acylation reaction and/or ester-exchange reaction is carried out in the presence of an organic basic compound containing one nitrogen atom and satisfying the following inequality (1): 0< A+ 0.4× B (1) wherein, A and B satisfy A ={( Ec h+ −Ec )/( Ep h+ −Ep )}−1 and B =(φ f/φfp )−1; Ec denotes the heat of formation of the organic basic compound containing one nitrogen atom in a molecule; Ec h+ denotes the heat of formation of a compound which is the organic basic compound coordinated by proton (H + ) to the nitrogen atom; Ep denotes the heat of formation of pyridine; and Ep h+ denotes the heat of formation of a compound which is a pyridine coordinated by proton (H + ) to the nitrogen atom to pyridine; φf denotes the value calculated by dividing the entire surface area by (L+a) 2 , wherein the surface area is the portion shed over by light from a point light source without being obstructed by atoms in the molecule other than the nitrogen atom, in the spherical inner part with a radius (L+a) from the origin, which is the center of nitrogen atom of the organic basic compound containing one nitrogen atom in a molecule in the most stable steric coordination, assuming that the point light source is positioned at the origin,; L denotes the distance from the origin to the center of the atom remotest in the molecule; and “a” denotes the van der Waals radius of the atom in the molecule; and φfp denotes the value of φf in the case the organic basic compound containing one nitrogen atom in a molecule is pyridine.