LOW FORMALDEHYDE AND HIGH WET STRENGTH FIBROUS NONWOVEN SUBSTRATE TREATED WITH A VINYL ACETATE ETHYLENE COPOLYMER OR A VINYL ACETATE POLYMER DISPERSION

摘要

An aqueous composition includes polyvinyl alcohol, an acid having a pKa of at most 4.0, and a dispersion of a polymer in which vinyl acetate units constitute at least 60 wt % of the polymer. The polymer does not contain units of any N-methylol-containing monomer, and at least a portion of the polyvinyl alcohol is present in the form of an emulsion stabilizer for the polymer. The wet strength of a fibrous nonwoven substrate can be increased by applying one or more aqueous compositions that together include polyvinyl alcohol, an acid having a pKa of at most 4.0, and a dispersion of a polymer as described above, followed by a final drying step. A fibrous nonwoven article can be prepared in this way.