An objectionable coating gradually formed on metal surfaces of molds during processing of plastics due to extraction and deposition of some ingredient such as pigment, lubricant, stabilizer or plasticizer. Found on http://www.blowmachines.com/glossary1.htm
An objectionable coating gradually formed on metal surfaces of molds during processing of plastics due to extraction and deposition of some ingredient such as pigment, lubricant, stabilizer or plasticizer.