SECURITY PAPER AND PROCESS FOR PREPARING THE SAME

摘要

The invention relates to a security paper for valuable documents and to a process for preparing the same. According to the invention, the paper exhibits high protection degree due to a system of marking elements consisting of a dark-red fibre visible at day light, a fibre of green fluorescence in UV, a fibre with blue fluorescence in UV, a yellow fluorescent pigment visible in UV and 3 chemical compounds with colour reaction upon attack of the paper with chemical substances. The process claimed by the invention consists in forming a mixture consisting of 30...70% resinous trees cellulose sulphate and 70...30% deciduous trees cellulose sulphate, at a grinding degree of 55°SR, to which there are added 9% Ca carbonate, 0.003% fluorescent pigment, 0.024 % dark-red fibres, 0.020% green fluorescence fibres, 0.14% chemical compound for the colour reaction upon solvent attack of paper, 1.5% sizing agent, 0.5% retention agent, the paper pulp being then passed on the watermarking roll, sized in the sizing press with a 6% starch solution wherein there are dosed 0.5% compound for the colour reaction upon the base or acid attack of the paper and 1.5% compound for the reaction upon the chlorine attack, the resulting paper tape being finally dried.