In the food and beverage industry, containers are transported by conveyors, oftentimes at very high speeds. The containers may comprise many different materials including metals, glasses, papers such as treated papers and waxed papers, polymeric materials, and the like. During processing, the containers may sit on the conveyors for a period of time due to a back up on the conveyor. While the containers are stopped, the conveyor belt is often still moved continuously. In order to facilitate the smooth transportation of the containers on the conveyor, a lubricant composition is applied to the surface of the conveyor belt and/or the container.
In addition to having different types of containers and container materials, the conveyor may be made of different materials such as stainless steel and acetal. It is generally accepted in the industry that not all conveyor lubricants are equally effective at lubricating different types of container and conveyor materials, and some lubricants may be detrimental to certain materials such as polymeric containers. For example, phosphate esters are not as effective at lubricating a conveyor transporting glass containers. Further, lubricants such as amines, alcohols, and potassium hydroxide are incompatible with polymeric containers such as ethylene therephthalate homopolymers and copolymers (i.e. PET containers). It is known that exposure to incompatible lubricants will cause a phenomenon in PET containers called environmental stress cracking (crazing and cracking that occurs when the plastic polymer is under tension). Consequently, if a plant is using multiple types of container materials the plant usually has to switch conveyor lubricants when it changes the container on a line, or stock multiple lubricants which is time consuming and costly. It is against this background that the present invention has been made.
USPTO Backgrounds
USPTO Backgrounds