Prodn. of security paper - protected against alternations, by incorporation of fibres

摘要

The process which is additional to that claimed in 510203, consists of addn. of a proportion of small fibres, pref. of wool, rayon or silk, bleached and dyed and opt. luminescent, to the original mixt. of cellulose paste and colourant soln., keeping the paste at a neutral ptt. The fibres can be chemically treated previously, so that moistening the paper with water, benzene, petrol or acids produces a colour change. It is applicable to security papers such as bank documents, bonds, etc.