PVC, POF as the main raw material of the shrinking film, with high puncture resistance, good shrinkage and a certain degree of shrinkage stress. Mainly used for a variety of product sales and transportation process, used to secure, cover and protect the product. Shrink packaging is not only beautiful appearance, but also play a moisture, dust, anti-loose, anti-theft, the role of collection. This article describes the shrink film products, some of the basic quality requirements, due to limited levels, the error is inevitable, so only for excellent friends in the community reference and correction:
First, the basic appearance requirements
1, the surface: not broken, perforation, deformation, incomplete, scratched or scratched.
2, flatness: no dead fold, no damage, no more than 0.8mm black spots and impurities, no significant bubbles.
3, health: dust pollution, crystal point per square meter greater than 3, no dust, grease; is strictly prohibited insects, dander or irritating odor.
4, color: uniform, transparent or light blue.
5, transparency: consistent with the standard.
Second, the product material and structural requirements
1, long, diameter: with the accuracy of measuring instruments to measure, heat shrink film length, diameter should be confirmed in the two sides of the standard value and tolerance range (wide tolerance range of the maximum shall not exceed 5mm).
2, material: meet the standard sealed sample products, shall not be changed
3, thickness: with the accuracy of measuring instruments to measure, heat shrink film thickness should be confirmed in both the standard value and tolerance range (double layer thickness shall not exceed the standard requirements ± 1 wire)
(1.5 for the density, 5.6 for the double layer thickness, 100000 for the fixed value), can be obtained for each weight, and then 1000g (1) 1kg) divided by the calculated weight, you can get the required value, only the number should be confirmed within the scope of tolerance.
Third, shrink film function requirements
1, opening: easy to rub open.
2, the heat shrinkage: randomly selected samples, PVC film only into the boiling water for 1 minute, take out to measure its longitudinal, horizontal size, lateral shrinkage of 20-45%, longitudinal shrinkage of 12-30%; POF film For 45-60%.
3, on the machine test: according to the production conditions of contraction, shrink statistics after the failure rate.