CONTAMINATION PREVENTING AGENT COMPOSITION

[Object] To provide an anti-contamination agent composition that can effectively prevent pitch contamination in a dry part. [Solving Means] The present invention relates to an anti-contamination agent composition for preventing pitch contamination in dry part D of a paper-making process， which contains a linear polysiloxane compound represented by following formula (1) and a cyclic siloxane compound. [wherein substituents R1 represent a hydrogen atom， an alkyl group， a methylphenyl group， a polyether group， a higher fatty acid ester group， an amino-modified group， an epoxy-modified group， a carboxy group， a phenol group， a mercapto group， a carbinol group， or a methacryl group in one molecule， and the number n of repeating siloxane units represents an integer from 20 to 1430].