method for printing on paper halogrammes, kinogrammes, networks or other microgravures with diffraction optical effects

摘要

A micro etched printing is obtained by an embossing method, wherein the paper passes through an embossing group (...) (...), which is composed of an embossing roller (...) with the micro etch and a counter pressing roller (...).SAID PROCESS BEING PERFORMED AFTER HUMIDIFICATION OF THE PAPER, AT A TEMPERATURE AND A PRESSURE ON THE PAPER THAT PASSES BETWEEN THE TWO CYLINDERS INCLUDED IN THE RANGE 90-220 ° C DEGREES C AND 20-120 KG / MM2 RESPECTIVELY, PREFERABLY 130-170 ° C ET 40-100 KG / MM2 RESPECTIVELY