There are many kinds of molds in the blister packaging industry. First of all, the molds used on the blister machine are: blister aluminum mold, blister copper mold, blister plaster mold, and upper mold. Among them, the blister aluminum mold is generally engraved and processed by cnc computer, which is of high quality and durable, suitable for mass production; the blister copper mold is essentially just a thin layer of copper skin, which is filled with plaster. Compared with aluminum molds, mass production has poor heat transfer and short service life. Gypsum molds are mainly used for small batch production and proofing. Among them, red gypsum has high hardness and is suitable for small batch production. Yellow gypsum has low hardness and is mainly used for small samples. The upper mold is in the production process of blister molding. It is necessary to apply a force from above to promote the shaping during the shaping. It is generally made of steel and attached with cloth. The dies used in the punching machine are: iron knife die, laser woodworking knife die, metal punch die, etc. Among them, iron knife dies are mainly used in mechanical punching machines, and laser knife dies are mainly used in hydraulic punching machines. For products with special shapes, metal punching machines are needed for cutting.
The molds used in later packaging are sealing molds, high-frequency molds, etc., together with the sealing machine and high-frequency machine to heat seal the blister and the blister, or between the blister and the paper card. Common materials for blister packaging The sheet material for blister packaging is called hard film or film. Commonly used are: PET (polyethylene terephthalate) hard film, PVC (polyvinyl chloride) hard film, PS (polystyrene) ) Hard film. PS hard film has low density, poor toughness, easy to burn, and styrene gas (belonging to harmful gas) will be generated during burning, so it is generally used to produce plastic trays for various industries. PVC hard film has moderate toughness and is not easy to burn. It will produce chlorine gas when burning, which will cause certain impact on the environment. PVC is easy to heat seal. It can be sealed with a sealing machine and a high-frequency machine. It is the main raw material for producing transparent plastic products. PET hard film has good toughness, high transparency, easy to burn, and does not produce harmful gases during combustion. It is an environmentally friendly material, but the price is high. It is suitable for high-end plastic products. Blister shells in European and American countries generally require PET hard film, but It is not easy to heat seal, which brings great difficulties to packaging. In order to solve this problem, people use a material called PETG ethylene glycol modified-polyethylene terephthalate. Heat sealability, PET also has high environmental protection and transparency, but the price is higher.