Medical plastic bottles should have enough stiffness and beautiful appearance, to attract the eye of the user in the appearance, to ensure that consumers can have many choices and usability in use. The most common shapes of medicinal plastic bottles are round, square and oval. From the point of view of use, they have their own advantages and disadvantages. The round plastic bottle has higher stiffness, but its shape is not beautiful. The square plastic bottle is beautiful in appearance, but it is not easy to control the uniform thickness of the plastic bottle wall when forming.
Pharmaceutical plastic bottles in the production of good control and design, according to a certain production and processing technology for production and production, and has good performance and function, can fully show important value in the industry.
1. In the design of extruded medical plastic bottles, if the material is high density polyethylene or polypropylene, the cross section of plastic bottles should be rectangular or oval. For low density polyethylene or other flexible plastic bottles, the cross section should be round. This allows the contents to be easily extruded from the plastic bottle. The plastic parts used together with the plastic bottle mouth are mainly caps and sealers. The design of plastic bottle mouth should be emphasized; It is the weak part of the mechanical properties of plastic bottles to consider how to make the plastic bottle mouth fit with the lid and sealer better. Therefore, the bottom of medicinal plastic bottles is generally designed to be concave; The corner office of plastic bottle, reach inside concave place, do larger arc excessive. In order to facilitate the stacking of plastic bottles, increase the stacking stability of plastic bottles, the bottom of plastic bottles should be designed inner groove.
2. When labeling is used on the surface of pharmaceutical plastic bottles, the labeling surface should be smooth. A “frame” can be designed on the surface of the plastic bottle so that the label is positioned accurately and does not move. In blow molding, the first part of the billet blowing contact, always tend to the first hardening part. Therefore, the wall thickness of this area is also larger. The edge and corner part is the last contact part of billet blowing, and the wall thickness of this part is small. Therefore, the edges and corners of plastic bottles should be designed as rounded corners. Change the surface shape of plastic bottle, such as plastic bottle in the middle relatively thin, increase the circumferential groove or convex rib of the surface of plastic bottle, can improve the stiffness and bending resistance of plastic bottle. Longitudinal grooves or stiffeners can eliminate migration, sagging or deformation of plastic bottles under long-term load.
3. Because most plastics have notch sensitivity, plastic bottles in the sharp corner, the root of the mouth thread, neck and other parts, easy to produce cracks and cracking phenomenon, so these parts should be designed into rounded corners. For the transfer of rectangular plastic bottles, most of the load of plastic bottles need to be supported, so the local increase in the wall thickness, but also conducive to improving the stiffness and load strength of plastic bottles.
4. The printing surface of medicinal plastic bottles is the most concentrated part of consumers’ attention. The printing surface should be smooth and continuous; If the plastic bottle contains handle, groove, reinforcement and other structures, the design should be careful not to cause inconvenience to the printing operation. Oval plastic bottle, stiffness is also higher, but the mold manufacturing cost is higher. Therefore, in order to ensure the stiffness of plastic bottles, in addition to the selection of high stiffness materials, but also through the shape design of plastic bottles, enhance the stiffness and load strength of medical plastic bottles.
Post time: Nov-10-2021