METHOD OF MANUFACTURING SHEET FIBROUS FILTER MATERIAL Russian patent published in 2001 - IPC

FIELD: paper-and-pulp industry. SUBSTANCE: invention relates to paper and cardboard materials for filtration of liquids and gases. For that purpose, to unwound glass fiber is added binding agent: ground to 25-95 deg foliferous wood cellulose fiber, polyvinylacetate dispersion in amount 2-10% (based on the weight of absolutely dry glass fiber), and cationic polyamino-polyamido-epichlorohydrin resin (0.2- 3.0%). Pulp is then placed on screen to give paper or cardboard sheet. According to invention, polyvinylacetate dispersion is added to pulp either before addition of cellulose fiber to unwound glass fiber, or after mixing indicated mineral fiber with indicated cellulose fiber, whereas polyamino-polyamido-epichlorohydrin resin is added after all components are mixed or directly before placing pulp on screen. EFFECT: improved strength and filtration characteristics of material simultaneously with reduced dusting, corrosion of equipment. 3 cl, 1 tbl, 3 ex