Solvent for the chromogenic dye-precursor material for a pressure- sensitive recording paper sheet and a pressure-sensitive recording paper sheet prepared by using the solvent

摘要

Disclosed herein are a solvent for a chromogenic dye-precursor material for a pressure-sensitive recording paper sheet, comprising (1) 30 to 80% by weight of p-monoisopropylbiphenyl or a biphenyl mixture of not less than 80% by weight of p-monoisopropylbiphenyl, not more than 20% by weight of m-monoisopropylbiphenyl and not more than 10% by weight of diisopropylbiphenyl, and (2) 70 to 20% by weight of diisopropylnaphthalene or a naphthalene mixture of not less than 97% by weight of diisopropylnaphthalene, not more than 1% by weight of monoisopropylnaphthalene and not more than 2% by weight of triisopropylnaphthalene, and a pressure-sensitive recording paper sheet prepared by using the solvent.