Blister is a plastic processing technology. The main principle is to heat and soften the flat plastic sheet. It is vacuum-adsorbed on the surface of the mold and cooled to form. It is widely used in plastic packaging, lighting, advertising, decoration and other industries. The plastic forming technology, that is, the plastic sheet (plate) material hot forming processing technology, is one of the plastic secondary processing industrial technologies. It is different from one-time processing such as injection molding and extrusion. It is not for the plastic molding of plastic resin or pellets or for continuous molding with the same section of the die. It is not the use of machine tools, tools and other mechanical processing methods to cut a part of plastic materials. Down, obtain the required shape and size, but heat the plastic sheet (board), use the mold, vacuum or pressure to deform the sheet (plate) to achieve the required shape and size, supplemented by matching processes to achieve application purpose.