| abstract |
The present invention relates to paper products having temporary wet strength. The paper products contain cellulosic fibers that are treated with a polyaldehyde polymer having free aldehyde groups and a water soluble polyhydroxy polymer. The initial wet strength obtained with the combined use of these materials is significantly greater than that obtained by use of either the polyaldehyde or polyhydroxy polymer alone. At the same time, the wet strength decays at a rate that is rapid enough to enable the paper product to be flushed under conditions of normal use. Preferred polyaldehydes include cationic, aldehyde functionalized starches and cationic, aldehyde functionalized polyacrylamides. Preferred polyhydroxy polymers are polysaccharides having cis-hydroxyl groups in at least a portion of the main polymeric chain (i.e., polymer backbone). Preferred polysaccharides include those derived from one or more sugars selected from mannose, galactose, allose, altrose, gulose, talose, ribose, and lyxose. Economically preferred polysaccharides are guar gum, locust bean gum and ionic derivatives thereof. The polysaccharide is preferably a neutral polysaccharide or a charge balanced mixture of polysaccharides. |