Anti-soiling agent composition

A method for preventing pitch contamination on cylinders, calendar roll, canvas and breaker stack roll of a paper-making machine comprising spraying onto their surfaces an anti-soiling composition comprising a polysiloxane compound, the polysiloxane compound being represented by the following formula (1),

• wherein a substituent R1 represents a methyl group or an amino-modified group represented by the following formula (2), and the number n of repeating siloxane units represents an integer in a range from 100 to 800, and
• wherein a substituent R2 is a propylene group and a substituent R3 is an ethylene group, and the number m of repeating amino-alkylene units represents an integer that is 1,
• wherein the number of amino-modified groups per molecule of the polysiloxane compound is in a range from 0.5 to 5 so that a coat film is formed on a dry part region so as to disperse pitch, and the polysiloxane compound has a compounding ratio in a range from 0.1 to 40% by weight, and
• wherein the polysiloxane compound of the anti-soiling composition is applied to the cylinders, calender roll, canvas, and breaker stack roll in an amount per unit area of paper passing therethrough of from 10 μg/m2 to 10,000 μg/m2.