| 摘要 |
PROBLEM TO BE SOLVED: To provide a resin having flame retardancy, high refractive index, low dispersion characteristics, and high toughness. SOLUTION: The resin comprises a carbonate residual group, a phosphonic acid residual group represented by formula (1), and a divalent phenolic residual group represented by formula (2), wherein molar fractions between the phosphonic acid residual group and the carbonate residual group satisfy formula (3): 1≥(a)/[(a)+(b)]≥0.05 [wherein (a) is a molar number of the phosphonic acid residual group; and (b) is a molar number of the carbonate residual group], and its number-average molecular weight is≥30,000. COPYRIGHT: (C)2004,JPO
|
