Paper for engineering drawings - coated to improve covering power of ink and to reduce sensitivity to finger marks

摘要

The paper is treated with an aq. compsn. contng. only one salt of a divalent metal and an inorganic acid, and no nonionic surfactant, and then dried. The salt is pref. CaCl2 or BaCl2. Excellent ink lines are obtd. with sharp contours, producing good diazo copies and microfilms which are of better quality than those obtd. when using a nonionic surfactant.