Sintolube is a synthetic liquid lubricant based on silicon, for the conveyor belts of PET and polycoupled carton containers for liquid products, to be used in the food, cosmetic and pharmaceutical sector. Sintolube can be used with plastic conveyor belts and is compatible with the inks present on the containers. Sintolube is not sensible to the dilution water hardness and has been also suitably studied to avoid possible phenomena of stress cracking towards PET. Sintolube is non foaming, when utilized at optimal concentrations.