At present, the barrier test of package is usually divided into test of the body and test of the cap independently. However even though the barrier property of both the body and the cap is excellent, if there is a leakage in the joint point, the integral barrier property of the package would be decreased greatly. Therefore it is critical to test the integral barrier property of the package. This article is to introduce the test method of integral barrier property test of well capped bottle.
1. Current Situation of Barrier Property Test of Package
Package is one of the main forms for liquid packaging. Barrier property of the package would directly influence the shelf life of the products. Generally speaking, the better the barrier property of package is, the longer the shelf life will be. Products such as alcohol and perfume have special odor, which requires that the package should have better barrier property to oxygen and water vapor which may cause deterioration or influence the product quality. Moreover, the package should ensure that special fragrance of those products would not dissipate in process of storage.
Because the package is directly used in liquid packaging, there is no uniform shape or specification. As a result, the barrier property test of package would be more difficult than that of film. Most of the barrier property tests are focused on regular gases. In the past, gas permeance of package is estimated with test data of package sheet material. As the thickness of the wall of package is not homogeneous and the nature of the material may change in process of manufacturing of package, there is certain difference between the estimated results and the actual test results. With the development of testing technology, the oxygen permeability test method of package has been improved greatly. The introduction of ASTM F 1307 standard for oxygen permeability test of package is a milestone for the development and popularization of testing instruments for oxygen permeability test of package. And the test method is more scientific and accurate compared with the former test methods with low accuracy and reliability.
Except metal cans and pulp-molded aluminum package, one complete package mainly consists of bottle body and bottle cap. At present, the barrier test of package is usually divided into test of the body and test of the cap independently. However even though the barrier property of both the body and the cap is excellent, if there is a leakage in the joint point, the integral barrier property of the package would be decreased greatly. The joint point of the bottle body and bottle cap especially the detachable package is the most fragile point which may influence the barrier property of the whole package. It is similar to the sealing area of flexible package that if the sealing area is not sealed well, the package could not protect the content inside the package properly even though the packaging material is with excellent barrier property.
2. Integral Barrier Property of Package
At present, test method for integral barrier property test of capped bottle is not available in most of the testing instruments on the market. Based on the oxygen permeability test method of bottle body, Labthink developed the test method for integral barrier property test of capped bottle.
Apparatus: Labthink i-OXTRA 7600 Oxygen Transmission Rate Tester
Test Specimen: Glass Bottle with Metal Cap
Test Item: Oxygen permeance of bottle cap and joint point
Test Environment: Standard Laboratory Environment
2.1 Specimen Preparation
First, prepare qualified test specimen. The test specimen is prepared almost in the same way as that for oxygen permeability test of bottle body including preparation of testing devices and conditioning test specimen. It should be noted that the test specimen is mounted in a different way:
For the test of bottle body, the bottle is inverted and placed in the special bottle support provided by Labthink and then fill the prepared adhesive to seal the bottle mouth to prevent oxygen permeates through the joint point of bottle mouth and bottle support.
For integral barrier property test of bottle cap and bottle body, place the bottle upward on the center of the bottle support. Then fill the prepared adhesive evenly into the area between bottle body and the wall of bottle support. Make sure that the area between bottom recess and input and output pipes is also filled with adhesive. The finished specimen is shown in Figure 2.
It should be noted that the test accessories should not be mounted until the complete solidification of adhesive. Otherwise improper movement of specimen may cause failure of package sealing.
2.2 Mount the specimen and start the test
Mount the specimen, test accessories and the attached lower test chamber to the upper test chamber according to the instructions mentioned above. Then start the test. Test procedures for integral barrier property test of capped bottle are totally the same as those for oxygen permeability test of bottle body.
The test method of integral oxygen permeability test of capped bottle introduced in this article is modified on the basis of the common test method of oxygen permeability test of bottle body. Preparation of specimen and the test accessories are 2 critical steps in the whole testing process. This method is also applicable in the integral oxygen permeability test of metal cans and pulp-molded aluminum flexible package. It has found its wide application in controlling the barrier property and provides data support in optimization of package structure and reduction of manufacturing cost of package.
Detailed information,pls contact Emily Wu at email@example.com or visit our website: http://www.labthinkinternational.com/.
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