Method of reproducing manuscripts, copies to the machine, printed, drawings and other similar text

摘要

Formaldehyde is caused to react with salts, such as the hydrochloride, or aromatic amines, such as aniline, phenylenediamine or their homologues, preferably in the proportion of 1 molecule of amine salt to 1 1/2 -2 molecules of formaldehyde.