The shape and process of medicinal plastic bottles


Medical plastic bottles should have sufficient rigidity […]

Medical plastic bottles should have sufficient rigidity and beautiful appearance, can attract users' attention in appearance, and ensure that consumers can have many choices and usability in use. The most common shapes of medicinal plastic bottles are round, square, oval and so on. From the perspective of use, each has its own advantages and disadvantages. The round plastic bottle has high rigidity, but its appearance is not beautiful. The square plastic bottle is beautiful in appearance, but it is not easy to control the uniform wall thickness of the plastic bottle during forming.

Pharmaceutical plastic bottles should be well controlled and designed in production, made and produced according to certain production and processing techniques, and have good performance and functions, and can fully demonstrate important value in the industry.


1. When designing squeezed medical plastic bottles, if the material is high-density polyethylene or polypropylene, the cross-section of the plastic bottle should be rectangular or oval. For low-density polyethylene or other flexible plastic bottles, The cross section is preferably circular. This makes it easier for the contents to be squeezed out of the plastic bottle. The plastic parts used in conjunction with the plastic bottle mouth are mainly caps and sealers. The design of the plastic bottle mouth should be focused on; consider how to make the plastic bottle mouth better match the lid and sealer to the bottom of the plastic bottle, which is the weak part of the mechanical properties of the plastic bottle. Therefore, the bottom of medicinal plastic bottles is generally designed to be concave; the corners and concaves of the plastic bottles are all made with larger arcs. In order to facilitate the stacking of plastic bottles and increase the stacking stability of plastic bottles, the bottom of the plastic bottles should be designed with internal grooves.

2. When labeling is used on the surface of medical plastic bottles, the labeling surface should be flat. A "frame" can be designed on the surface of the plastic bottle, so that the label can be positioned accurately without movement. In blow molding, the first part of the parison that is blown into contact always tends to harden first. Therefore, the wall thickness of this part is also larger. The edge and corner part is the last contact part of the parison inflated, and the wall thickness of this part is small. Therefore, the edges and corners of the plastic bottle should be designed with rounded corners. Changing the surface shape of the plastic bottle, for example, the middle part of the plastic bottle is relatively thinner, and increasing the circumferential groove or rib on the surface of the plastic bottle can improve the rigidity and bending resistance of the plastic bottle. The longitudinal grooves or ribs can eliminate the deviation, sagging or deformation of the plastic bottle under long-term load.

3. Since most plastics have notch sensitivity, plastic bottles are prone to cracks and cracks at sharp corners, the root of the mouth thread, the neck and other parts, so these parts should be designed with rounded corners. For the transfer place of the rectangular plastic bottle, it is necessary to support most of the load of the plastic bottle, so locally increasing the wall thickness at this place is also beneficial to improve the rigidity and load resistance of the plastic bottle.

4. The printing surface of the medicinal plastic bottle is the most concentrated part of consumers. The printing surface should be smooth and continuous; if the plastic bottle contains handles, grooves, ribs and other structures, the design should be careful not to cause inconvenience to the printing operation. Oval plastic bottles have higher rigidity, but the manufacturing cost of the mold is higher. Therefore, in order to ensure the rigidity of plastic bottles, in addition to selecting high-rigidity materials, the shape design of the plastic bottles must be used to enhance the rigidity and load-bearing strength of medical plastic bottles.