Sealing Performance Test of Medical Plastic Bottle

Owing to its light weight, high strength, solid structure and excellent sealing characteristics, as well as moisture-proof and cleanliness performances, plastic bottle has found its wide applications in packing oral pills or liquid medicine. Moreover, medical plastic bottle coincides with the special packaging requirements for medicines and can be directly filled without cleaning or drying. In order to avoid the influences of light, heat and oxidization, etc., pharmaceuticals need bottles with excellent sealing performances, so that damp or deterioration will not occur during their validity period. Thus, it has been clearly stipulated in the relevant standards for the sealing performance of medical plastic bottles, which is a key index for manufacturers. Hereinafter, this article is to briefly introduce the sealing performance test of medical plastic bottle with Labthink MFY-01 Leak Tester.  

Sealing performance is referred to the sealing reliability of medical plastic bottle. Through sealing performance test, sealing integrity of the whole package could be guaranteed. Thus, excellent sealing performance of medical plastic bottle is a guarantee against moisture or deterioration during validity. It has been regulated in relevant national standards as follows: take a certain amount of medical plastic bottles, and fill each bottle with some glass balls. Then, tighten the closures of the bottles. The torque forces are listed below:

Diameter of closure (mm)	Torque Force (N· cm)
15～22	59～78
23～48	98～118
49～70	147～176

Then, submerge the bottle specimen into the water prefilled in the container with vacuum device, and vacuumize the test chamber to the vacuum degree of less than 27kPa and keep it for 2 minutes, during which no water should enter into the bottle, or no bubbles should be observed.

The working principle of Labthink MFY-01 Leak Tester is as follows: submerge the specimen into water and vacuumize the test chamber to form the pressure difference between the inside and outside of the specimen. Observe leakage of the specimen and how the specimen expands and restores to its original shape after vacuum released to determine the sealing performance of it. Labthink MFY-01 is fully automatic, easy to operate and user friendly; no more manual operation is needed besides inputting pressure value and duration. The above testing method is by visual observation which provides a qualitative determination. For quantitative determination of sealing and leakage property, the seal tester with positive pressure method should be used, e.g. Labthink LSSD-01 Leak and Seal Strength Detector.

Besides the sealing performance, more indexes such as oxygen permeability and water permeability, etc. need to be tested for medical plastic bottle to guarantee the shelf life. For more information of other related testing instruments, please visit www.labthinkinternational.com.cn.