Patent ID: 7964062

Claim:
A paper treating agent comprising 100 parts by mass of an organopolysiloxane (A) which is at least one member selected from the group consisting of an organopolysiloxane (A1), an organopolysiloxane (A2), and an organopolysiloxane (A3), wherein said organopolysiloxane (A1) is represented by the following formula (1) wherein R 1 is methyl, and X 1 is a radical represented by the following formula, wherein a1, b1 and d1 are such numbers that the organopolysiloxane (A1) has a viscosity at 25° C. of from 0.05 to 500 Pa·s, and b1 and d1 may be zero, said organopolysiloxane (A2) has at least two hydroxyl groups and is represented by the following formula (2) wherein R 1 is methyl, R 3 is a hydroxyl group, and X 2 is a group represented by the following formula: wherein a2, b2, c2 and d2 are such numbers that a viscosity at 25° C. of the organopolysiloxane (A2) ranges from 0.05 to 500 Pa·s, and b2, c2 and d2 may be zero, and said organopolysiloxane (A3) has at least two alkenyl groups and is represented by the following formula (3), wherein R 1 is methyl, R 2 represents an alkenyl group, and X 3 is a group represented by the following formula: wherein a3, b3, c3, d3, and e3 are such numbers that the organopolysiloxane (A3) has a viscosity at 25° C. of from 0.05 to 500 Pa·s, and b3, c3, d3 and e3 may be zero and alpha and beta are integers of 0 to 3, 0 to 6 parts by mass of a cross-linking agent (B) which is an organopolysiloxane having at least three SiH bonds or hydrolyzable groups represented by the following compositional formula R 1 f H g SiO (4−f−g)/2 or the following compositional formula R 1 f W g SiO (4−f−g)/2 wherein R 1 is methyl, W is a hydrolyzable group which is at least one member selected from the group consisting of alkoxy groups, acyloxy groups, alkylamino groups, amido groups, and oxime groups, and 0≦f≦3, 0<g≦3, and 1≦f+g≦3, said cross-linking agent (B) being used in combination with said organopolysiloxane (A2) or said organopolysiloxane (A3), 50 to 1,000 parts by mass of cellulose methyl ether (C), wherein 0.7 to 2.3 hydroxyl groups per glucose unit of said cellulose methyl ether are etherized, and a viscosity of an aqueous 2% solution of said cellulose methyl ether is from 2 to 100 mPa·s at 20° C., 0 to 5 parts by mass, calculated as an active ingredient, of a catalyst (D), 100 to 100,000 parts by mass of water (E), and 0.1 to 100 parts by mass of a surfactant (F), provided that polyvinyl alcohol is excluded.