Test method for shrinkage of BOPP film

Abstract: the shrinkage performance of BOPP film is an important factor that affects the compactness and flatness of cigarette packaging appearance This paper introduces a test method of shrinkage performance of BOPP packaging film by testing the shrinkage performance of BOPP packaging film samples, and details the test principle, parameters and application scope of the test equipment Labthink blue light fst-02 film thermal shrinkage performance tester, which provides a reference for enterprises in selecting film shrinkage performance test equipment and test methods Key words: BOPP film, cigarette film, shrinkage film, shrinkage performance, shrinkage rate, shrinkage force, heat shrinkage force, cold shrinkage force, film heat shrinkage performance tester 1 Meaning BOPP film has become an ideal cigarette packaging material due to its advantages of high brightness, good glossiness, high stiffness, high moisture resistance and fragrance retention The shrinkage of BOPP film directly affects the smoothness and beauty of cigarette appearance Common cigarette packs are mainly divided into two types, one is soft cigarette pack, the other is hard cigarette pack For the former, it is generally required that the shrinkage rate of cigarette film used in packaging is low and the shrinkage force is small, so as to prevent the deformation of cigarette pack due to excessive shrinkage and even the extrusion deformation of cigarettes For the latter, it is required that the shrinkage rate and the shrinkage force of cigarette film are relatively large, so as to keep the cigarettes flat, even and uniform for a long time Compact packaging Therefore, it is of far-reaching significance to strengthen the detection of cigarette film shrinkage performance, ensure the suitability and uniformity of shrinkage performance, and improve the appearance quality of cigarettes Figure 1 BOPP smoke film 2 At present, there is no national standard related to BOPP smoke film in China The reference standard for this kind of film is db53 / t20-2008 biaxially stretched polypropylene film for smoke There are two main methods to test the shrinkage performance of the shrink film: oil bath method and oven method For example, the method specified in GB / t10003 is oven method, and the method specified in GB / t13519 is oil bath method However, no matter which method is used, it can only test the shrinkage of the shrink film, but it can't test the force value produced by the film in the process of heat shrinkage or cooling In this paper, it is tested according to the iso14616 standard, which stipulates the test method of the shrinkage, heat shrinkage, cold shrinkage and other performance parameters of the shrink film 3 Test sample BOPP film used by a brand of cigarette 4 Test equipment the test equipment used in this paper is the fst-02 film shrink performance tester developed according to iso14616, which is independently developed and designed by Jinan Languang Electromechanical Technology Co., Ltd Fig 2 test principle of fst-02 film shrinking performance tester 4.1 After the shrinkage film reaches the shrinkage temperature, the film shrinks, the size changes, and a certain force value is generated at the same time In this equipment, the force value sensor and displacement sensor are respectively configured Through automatic and real-time testing of the displacement and force value changes during the heating and cooling process of the shrinkage film, the shrinkage rate, heat shrinkage force, cold shrinkage force and other index parameters of the shrinkage film are obtained 4.2 the measuring range of contraction force of equipment parameters is 0.2 ~ 30n, and the measuring accuracy is ± 0.2%; the measuring range of thermal contraction displacement is 0.125 ~ 70mm, and the measuring accuracy is ± 0.125mm It can be used to measure the thermal shrinkage parameters of the sample The temperature control range is from room temperature to 210 ℃, and the control accuracy is ± 0.5 ℃ The equipment can test three groups of samples at the same time The equipment can display the heat shrinking force, cold shrinking force and heat shrinking rate in real time 4.3 scope of application (1) it can be used to test the thermal shrinkage, cold shrinkage and shrinkage of heat shrinkable film materials under certain test conditions (2) it is applicable to iso14616 and din53369 standards 5 Test process (1) sample preparation: cut 10 samples with a width of 15.0mm and a length of more than 100mm along the longitudinal direction of the BOPP smoke film samples with a sampler, and hole the samples with a special sampler The samples were divided into five groups Two samples in each group were used to test the shrinkage rate and the shrinkage force Use the same method to cut 5 groups of samples along the transverse direction Fig 3 thickness test of a group of samples (2): test at least 3 points, and the thickness of the samples is the arithmetic mean of the test results (3) sample clamping: take 3 groups of samples from the longitudinal or transverse samples and clamp them in 3 groups of clamps of the equipment Figure 4 parameter setting of each group of sample clamping figure (4): set the test temperature, end temperature and other test parameters of the heating chamber, click the start test option to start the test (5) test: when the temperature in the heating cabin of the equipment reaches the test temperature, the sample will enter the cabin automatically, and the test will start timing The sample will heat shrink and generate heat shrink force When the heat shrink force meets the setting conditions, the sample will automatically exit the cabin, and the force value generated thereafter is the cold shrink force The equipment automatically records and displays the thermal shrinkage force, cold shrinkage force and shrinkage rate during the process from the sample entering the cabin to the end of the test in real time At the end of the test, the equipment shows the big shrinkage, big heat shrinkage and big cold shrinkage of each group of samples (6) repeat the operation of (3) ~ (5) until the five groups of samples in the transverse and longitudinal directions are tested 6 The results showed that the shrinkage of BOPP film was 8.34% in longitudinal direction, 0.08n in cold shrinkage and 0.31n in heat shrinkage, 15.07% in transverse direction, 1.29n in cold shrinkage and 2.71n in heat shrinkage 7 Conclusion Fst-02 film shrink performance tester is a kind of testing equipment that can test shrink rate and shrink force at the same time It overcomes the defect that traditional testing equipment and testing method can't test shrink force of shrink film, and the temperature control of the test, the accuracy of the test results is high, the repeatability is good, the operation is simple, and it is a testing equipment with strong practicability Labthink Languang is a company famous for developing and manufacturing packaging testing equipment and providing packaging testing services The testing equipment and services involved cover food, medicine, automobile, textile, daily chemical, health care products and other fields To learn about the relevant service information, you can visit Jinan Languang company or call for consultation The more you understand, the more you trust! 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