Farbbildner fuer druckempfindliches Wiedergabepapier und Verfahren zu dessen Herstellung

摘要

A pressure sensitive recording paper comprising a paper substrate and a coating thereon comprising a color former which comprises a member selected from the group consisting of acid-treated dioctahedral montmorillonite clay minerals and mixtures of such minerals with natural dioctahedral montmorillonite clay minerals, the minerals having a secondary color development property, K2, of at least 1.40, the value of K2 being represented by the formula K2 = R430/R 550 + 1/2 (1-R550) wherein R430 and R550 are reflectances of light having wavelengths 430 m mu and 550 m mu , respectively, when the minerals are developed by benzoyl leuco methylene blue.