| 摘要 |
FIELD: paper industry. ^ SUBSTANCE: method is intended to impart dirt and/or moisture resistance to porous substrate for protected documents, and also relates to dirt and/or moisture resistant protected document. Method includes application of dirt and/or moisture resistant compound onto opposite surfaces of porous substrate having porosity of approximately 20-100 millilitres per minutes and its impression into pores of substrate. At the same time compound penetrates and spreads at least in part of substrate thickness, then excess compound is removed from opposite surfaces of substrate. Coating press is used to impress dirt and/or moisture resistant compound into pores of substrate. ^ EFFECT: specified compounds applied by suggested method do not darken optically variable effects generated by non-porous film structures on the basis of microlenses, which may be used on or inside these protected documents, and thin layers of fibres applied and this introduced into parts of protective devices in protected documents containing windows with dirt and/or moisture resistant properties according to the present invention, demonstrate improved durability. ^ 22 cl, 1 ex |
