Blister forming is the main process of all blister packaging processes. Basically, the blister forming methods can be divided into the following four types.

①Blister molding machine (negative pressure molding).

Apply vacuum to suck the heated and hardened film into the blister socket of the formed pancreas into a certain geometric shape, thereby completing the blister forming.

Blister molding generally adopts roller molds.

The size of the formed blister is small, the shape is simple, the blister is stretched unevenly, and the top is thinner.

②Blow molding (positive pressure molding).

The compressed air is used to blow the heated and hardened film into the blister pocket of the forming mold to form a blister with the necessary geometric shape.

The formed blister has a relatively average wall thickness and a broad shape, which can form a large-sized blister. Blow molding is mostly used in plate molds.

③The punch of the medical blister machine assists blow molding.

With the help of the punch, the heated and hardened film is pressed into the mold cavity.

When the punch is completely pressed in, the compressed air is introduced to make the film close to the inner wall of the mold cavity to complete the forming process.

The size of the punch is about 60% to 90% of the molding cavity.

Reasonable design of punch outline size, punch pushing speed and pushing interval, can obtain blister with average wall thickness, wide edges and corners, larger size and complicated shape.

Punch auxiliary forming is mostly used in flat blister packaging machines.

④The male and female dies of the pharmaceutical blister machine are cold stamped and formed.

When the packaging material is more rigid, the thermoforming method is obviously not practical, but the cold stamping method of convex and concave molds is adopted, that is, the convex and concave molds are closed, and the film is formed, in which the air is squeezed out by the exhaust holes in the forming mold.