| 摘要 |
PURPOSE:To obtain an optical material excellent in optical properties, heat resistance and impact resistance and good in moldability, by using a polyester formed by condensing two specified carboxylic acid compounds with a diol as a component. CONSTITUTION:An optical material comprising a polyester obtained by condensing carboxylic acid compounds of formulas I and II and/or carboxylic acid compounds of formulas III and IV with a compound having two hydroxyl groups in the molecule. In the formulas, R is a 1-6C alkylene group, R<1> and R<2> are each H or a 1-3C alkyl, X<1> is H or a 1-3C alkyl, X<2> is a halogen and n is 1 or 2. As said compound having two hydroxyl groups in the molecule, one containing an aromatic diol having an aromatic ring in the molecule as a component is desirable. By using such an aromatic diol as a condensation component, the obtained polyester can be given very excellent heat resistance. |
