Verification of Shrinkage Performance of External Shrink Films for Yogurt Six and Eight Cups

Abstract : The yoghurt cup products often use a multi-joint cup series such as a six-joint cup and an eight-joint cup. The outside of the yoghurt cup is usually wrapped with a heat-shrinkable film in order to achieve a compact and beautiful effect and prevent the yoghurt cup from being scattered or damaged. Whether the heat shrinkable film has good bonding effect and tightness in the process of use, it needs to monitor the shrinkage, shrinkage and other indicators. This article uses a multi-functional film heat shrinkability tester, combined with the ISO 14616 standard to verify the contraction performance of the external heat shrinkable film of the yoghurt eight- joint cup. The test principle, parameters and testing process of the equipment are described in detail. It can be used for shrink film production and application. Industry provides technical reference.

Keywords: yogurt cups, six / eight cups, multiple cups, heat shrinkable film, firmness, conformability, shrinkage, shrinkage, shrinkage, shrinkage, shrinkage

Test significance:

Yoghurt cup products are mostly packed in multi-joint cups. On the market, six cups and eight cups are commonly used, and a plurality of connected yogurt cups are bundled together using a heat shrinkable film. The heat shrinking film is used to make the package compact and the yogurt Cups are not easily scattered, can clearly show the appearance of the product, improve product quality. The outer heat shrinkable film material of the yogurt cup is mostly POF , namely POF three-layer co-extruded heat shrinkable film, which has the advantages of high shrinkage, good cold resistance, high transparency and good flexibility, and uses steam or hot air passages when used. It is heat-treated so that the heat-shrinkable film is tightly attached to the outer surface of the yogurt multi-joint cup.

Heat shrinkable film is a commonly used outer packaging material, and has the advantages of compact packaging, transparent appearance, and strong fit. Heat-shrinkable films are manufactured after being stretched under a high-temperature environment and then rapidly reduced in temperature. When the heat shrinkable film is used, it is heated again to the temperature at which it is stretched, and the molecular chain of the material is restored to the disordered crimped shape, that is, it shows a thermal shrinkage phenomenon. When the heat shrinkable film is lowered to room temperature, a shrinkage force is generated so that the shrink film is firm. If the shrinkage rate of the heat shrinkable film during the heat shrinkage is too large, or the shrinkage force (including the shrinkage force and the shrinkage force) is too high, the consumption of the film may easily increase, and the compactness of the yoghurt cup or the film may be too tight. The phenomenon of breakage occurs; if the shrinkage rate of the heat shrinkable film is small or the shrinkage force is too low, the film does not fit the yoghurt cup and the packaging is loose, resulting in the phenomenon that the serial cup product is easy to fall off. Therefore, before the use of heat shrinkable film should strictly monitor the relevant shrinkage properties, such as shrinkage, thermal shrinkage force, shrinkage force and other performance indicators, in order to ensure that the yoghurt multi-cups external packaging compact, not easy to damage, and reduce packaging costs.


Yogurt six 1 / cup Eighth

Detection method:

At present, the heat shrinkable properties of domestic heat shrinkable film product standards are mostly determined by oven or oil bath heat shrinkage. However, these two test methods can only detect the heat shrinkage rate, and the shrinkage force such as shrinkage force and shrinkage force cannot be obtained, and the compact effect of the film cannot be evaluated. Therefore, this test refers to the use of the standard ISO14616-1997 " Test of shrinkage properties of plastic polyethylene ethylene copolymers and their mixtures heat shrinkable film ", using air heating principle (ie, air bath) to test various shrinkage properties of films, including heat Shrink force, shrinkage force, shrinkage, shrinkage time and other indicators.

1 , test equipment

In this paper , the FST-02 thin - film heat shrinkability tester independently developed by Labthink was used in combination with the above-mentioned standards to detect POF heat-shrinkable film samples used by a certain manufacturer for yoghurt eight-joint cups .

FST-02 thin - film heat shrinkability tester has a high-precision force sensor and displacement sensor, which can accurately measure the heat shrink performance parameters of the test sample. The test sample can have a contraction force range of 0.2 ~ 30 N (the contraction force measurement accuracy is ± 0.2 % ), and can customize a wider range of force values ​​according to special requirements; test sample thermal shrinkage displacement range of 0.125 ~ 70 mm (heat shrinkage displacement measurement accuracy of ± 0.125 mm ); test heating cavity working temperature range Room temperature ~ 210 °C (control temperature accuracy ± 0.5 °C ); equipment can test 1 ~ 3 groups of samples, the test sample size is 130 mm × 15 mm .

The device meets a number of national and international standards: ISO 14616 , DIN 53369 , and can accurately determine the thermal shrinking, shrinking force, and shrinkage properties of plastic films in the heat shrink process.

Figure 2 FST-02 Thin Film Thermal Tester

2. Preparation of sample

POF shrink film along the horizontal, vertical respectively, each cut out to a width of 20 samples of 15 mm, 1 to 2 groups per sample, i.e. horizontal and vertical samples of each group 10, respectively, for each sample Thermal shrinkage, shrinkage force, shrinkage test. The length of the specimen shall ensure that there is an effective length of 100 mm between the grips . Test specimen thickness, at least 3 points, averaged. With a special sampler, two round holes are drilled on the surface of the sample to facilitate the clamping of the sample.

3. Test conditions

Venue: Jinan Languang Packaging Safety Testing Center Test Conditions: 23°C, 50% RH Test Index: Maximum shrinkage force, maximum shrinkage force, shrinkage rate

4. Test procedure

4.1 Test principle

The specimens were connected to a displacement sensor and a force sensor, respectively. The temperature was rapidly increased to the contraction temperature, and then the system was cooled. The system monitored in real time the contraction performance curves of the sample after it was heated in a closed heating chamber, and the thermal shrinkage force and cold were automatically recorded. Shrink force, shrinkage, and set temperature, etc.

4.2 Test procedure

FST-02 Thin Film Thermal Shrink Tester can accurately, quickly, and conveniently test the shrinkage performance of heat shrinkable film:

Installation specimen: the specimen of which each have a completely flat specimens mounted on the force sensor, force sensor zero tension. The other sample must be completely flat between the holder arm and the clamp on the displacement sensor. The effective length of each set of specimens is 100 mm .

Figure 3 sample preparation and loading process

According to the reference temperature of the POF heat shrinkable film, test parameters such as test temperature and end temperature are set, and the test is started by clicking the start test option. When the temperature in the heating chamber of the equipment reaches the test temperature, the sample automatically enters the chamber. When the test begins, the sample heats up and shrinks, and when the value of thermal shrinkage decreases by about 15% to 30% , the sample Leave the heating cabin and stop timing. The parameters such as the maximum shrinkage force, the maximum shrinkage force, the shrinkage rate, and the appearance time of the maximum shrinkage force appear within 15 to 30 seconds at the set temperature . Repeat the above steps until the horizontal and vertical 10 groups of samples have all been tested. Calculate the average value of maximum shrinkage force, maximum shrinkage force, and shrinkage rate. Set the temperature to achieve the maximum shrinkage of the heat shrinkable film in 15 ~ 30 seconds. If the recorded maximum shrinkage force value of the sample is less than 15 seconds when placed in the heating mantle , gradually reduce the set temperature by 10 °C and repeat the test until the maximum contractile force value appears between 15 seconds and 30 seconds. On the contrary, if the maximum contractile force is reached for more than 30 seconds, gradually increase the set temperature by 10 °C and repeat the test until the maximum contractile force occurs between 15 seconds and 30 seconds.

4.3 test results

The average maximum thermal shrinkage force, maximum shrinkage force, and shrinkage ratio of the POF heat shrinkable film sample used in the Eight-fat yogurt cup at the set temperature were 0.85 N/15mm , 0.57 N/15mm , and 48.3% , respectively . The average maximum shrinkage force, maximum shrinkage force, and shrinkage rate were 0.59 N/15mm , 0.44 N/15mm , and 32.1% , respectively . From the above data, it can be seen that the POF heat-shrinkable film has good shrinkage both in the transverse direction and in the longitudinal direction, that is, the film can be better contracted around the cup body as an eight-piece cup yogurt outer package.

to sum up:

When using FST-02 film thermal shrinkage tester to test the external heat shrinkable film of yogurt multi-joint cup, the thermal shrinkage force, shrinkage force and shrinkage rate of the film can be tested at the same time, and the performance of the heat shrinkable film can be controlled in multiple dimensions. . The precision, intelligence, and test efficiency of the device are high. Besides the external heat shrinkable film of yogurt multi-joint cups, it can also be widely used in casing films, label films, cluster packaging films, sterilization tableware packaging films, sports goods, and processes. The heat shrinkable film of various products such as gifts and hardware is tested for shrinkage performance. Labthink has been committed to providing professional equipment and testing services to customers around the world, providing customers with a large number of reference materials for the performance of packaging materials. At the same time, Labthink provides various testing instruments and solutions for barrier properties, mechanical strength, and other properties. You can visit the website of Jinan Languang to view specific product information or call us directly . Labthink expects to enhance technical exchanges and cooperation with users in various industries.

Steel Lighting Pole High Mast

We have got CE certificate from 2015. We make can manufacture various types of high mast with lifting system for stadium highway parking lot and etc.

Our firm introduced whole set of good-sized numerical control hydraulic folding equipment(1280/16000) as well as equipped with a series of good-sized professional equipments of armor plate-flatted machine, lengthways cut machine, numerical control cut machine, auto-closed up machine, auto-arc-weld machine, hydraulic redressing straight machine, etc. The firm produces all sorts of conical, pyramidal, cylindrical steel poles with production range of dia 50mm-2250mm, thickness 1mm-25mm, once taking shape 16000mm long, and large-scale steel components. The firm also is equipped with a multicolor-spayed pipelining. At the meantime, for better service to the clients, our firm founded a branch com. The Yixing Jinlei Lighting Installation Com, which offers clients a succession of service from design to manufacture and fixing.

Steel Lighting Pole High Mast,30m High Mast Pole, High Mast pole for stadium

Jiangsu Xinjinlei Steel Industry Co., Ltd. , https://www.steel-pole.com