When recycling post-consumer paper, stickies are tacky substances contained in the paper pulp and process water systems of paper machines. Stickies have the potential to contaminate the components either within or around the equipment necessary in the that a Paper Mill follows in its , but would have otherwise excluded it in its routine cleaning and maintenance procedures. Contaminations of paper that are classified as tacky are also called stickies. The main sources for stickies are recycled paper, waxes, and soft adhesives.