Heat shrinkable film is a modern packaging polymer material for packaging food or industrial goods, using heat shrinkable machines. Heat-shrinkable film shrinks under the influence of temperature, repeating the shape of the object, without deforming the products. This process is called heat shrinkage. The product is wrapped by film, then briefly treated with hot air. As a result of heating and further cooling, the heat-shrinkable film coats the product.
The main characteristics of the heat-shrinkable film are the coefficient of shrinkage and stress. Shrinkage coefficient (degree of shrinkage) is the ratio of linear dimensions before and after thermal convergence. Shrinkage stress is the stress that occurs in the heat-shrinkable film when heated. The shrinkage stress is determined by the thickness of the shrink film, the material from which it is made, the temperature and duration of heating.
Плівка застосовується:
Тришарова, чорно-біла поліетиленова плівка з кольоровим друком, для пакування молочних продуктів широко використовується в молочній промисловості, для упаковки молочних продуктів.
Товщина таких плівок - 70-90 мкм. Кожен з шарів має своє призначення і містить спеціальні добавки.