| 摘要 |
<p>A wholly aromatic polyester having excellent heat resistance and toughness, and showing optical anisotropy when molten, and a composition thereof are provided. This wholly aromatic polyester showing optical anisotropy when molten is characterized by containing, as essential constituent components, the constituent units represented by general formulae (I), (II), (III), (IV) and (V), and in that, in relation to the total constituent units, constituent units (I) are 35-75 mol%, constituent units (II) are 2-8 mol%, constituent units (III) are 4.5-30.5 mol%, constituent units (IV) are 2-8 mol%, constituent units (V) are 4.5-30.5 mol%, and constituent units (II)+(IV) are 4-10 mol%. This polyester resin composition is formed by mixing 120 parts by mass or less of an inorganic or organic filler per 100 parts by mass of said wholly aromatic polyester.</p> |
