To obtain an agent preventing the incrementation of glue solution viscosity, preventing the formation of gels and sediment and the deterioration of paper strength and sizing properties when coated on a paper.
This ageproofing agent contains, as an active ingredient, an alkylene oxide adduct to a rosin compound of the formula: R1-O-(AO)n-R2 (R1 is a rosin or residue of its derivative; AO is an oxyalkylene group containing more than 60 mole % of oxyethylene group; (n) is an integer of 5-45; R2 is H, a 1-12C alkyl or alkenyl). The agent preferably contains polyacrylamides and/or polyvinylalcohols. The compound of the formula is obtained by deoxidizing a rosin or its derivative by adding 0.1-5wt.% of an alkaline material such as potassium hydroxide or sodium hydroxide as catalyst, then adding alkylene oxide, in drop wise manner, at 100-200°C, under pressure of 1-5kg/cm2.
KONISHI NOBUO
KIMURA SHINICHI
ABE HIROSHI
