Heat shrinkable film is a relatively advanced packaging method, which is widely used in food, ceramic products, tea sets, mechanical parts and other industries. The products packaged with heat shrinkable film can fully highlight the appearance, improve the display, beauty and sense of value of the products. At the same time, heat shrinkable film packaging also has the characteristics of sealing, moisture-proof, anti pollution and so on.

1、 Structure of heat shrinkable film

The film structure of heat shrinkable film packaging is similar to that of paper. The difference is that the film surface must be treated.

2、 Surface treatment of heat shrinkable film packaging

The principle of ink layer forming pattern on printed matter is penetration, volatilization, conjunctiva and solidification. However, due to the high film density, ink only volatilization, conjunctiva, curing process without penetration, so the surface of heat shrinkable film packaging needs special treatment. After the treatment, the surface tension of the heat shrinkable film is increased, so that the surface tension of the heat shrinkable film is greater than that of the ink, so as to achieve the correct combination of the ink and film materials.

3、 Three ways of heat shrinkable film packaging surface treatment

1. Corona treatment: through the high voltage charge to the film surface discharge treatment, so as to strengthen the surface energy and surface tension. Corona treatment is usually carried out in the film factory, because the surface tension is time limited, it is required to be strictly tested before printing. Therefore, some advanced equipment have prepress corona treatment device, in order to print high-quality film products.

2. Printing treatment: chemically change the surface characteristics of the film to make it suitable for ink printing or ribbon printing.

3. Surface coating: the use of chemical substances in the film surface coating, increase the surface tension, change the surface characteristics.