METHOD OF MAKING PAPER FOR DOCUMENTS AND PAPER MADE USING SAID METHOD Russian patent published in 2019 - IPC D21H21/54 D21H19/84 D21H21/40 

FIELD: pulp and paper industry.

SUBSTANCE: invention relates to pulp and paper industry, in particular, to production of paper for documents, which contains watermarks, protective fibers, protective threads and other protective features. Method of making paper involves preparing a basic suspension containing cellulose fibers, a binding agent, a sizing agent and a mineral filler. Method also involves preparation of an additional cellulose fibrous suspension, introduction of polymer microspheres into it, mixing and mixing it with the main suspension to produce a paper mass. Then paper web is formed from obtained paper mass on screen of paper-making machine. Paper web is processed on both sides in adhesive unit, pressed and dried to produce three-layer material with double-tee structure.

EFFECT: improved absorbability, clarity of the watermark, reduced deformation characteristics, curl, density when stabilizing paper opacity and maintaining functional properties of the article.

6 cl, 3 dwg, 2 tbl, 3 ex