Common problems and solutions in pre-coated film

Pre-coated film was born in the United States in the late 1980s. Since its inception, its environmental protection, ease of operation, high security and high efficiency have been recognized. China has introduced pre-coating technology since the 1990s. At that time, most of the pre-coated films were imported, and the price was quite expensive. Only a few companies in China can process low-grade high-temperature pre-coated films, which restricts the pre-coated film to some extent. China's application and promotion. At present, in the US film market, pre-coated film accounts for 97% of the total film, and the market share in Japan and Korea has reached 70%. In South America, some countries and regions in Africa, pre-coated films have also been People know and use. According to the National Press, Publication, Radio, Film and Television Administration, "Implementation of Green The Printing Results Report (2013) shows that in 2013, the national pre-coating film usage accounted for 25% of the total film coating, an increase of about 5% over 2012. Compared with the United States and other countries, the application scale of pre-coated film in China is still not very large, but with the development of green printing in China, green printing is deeply rooted in the hearts of the people. As a green environmental protection material, pre-coated film will be more and more affected by printing enterprises. Value.

Problems and solutions in the process of precoating film coating

Snowflake spots on the film product

Causes and solutions:

1 If the film pressure or temperature is improper, the pressure or temperature should be properly adjusted;

2 There are dust and impurities on the printed or pre-coated film. The surface of the printed product and the pre-coated film should be cleaned. The film should be in a clean and closed workshop.

The film is not firmly bonded and released

Causes and solutions:

1 If the ink is not dry, the drying time of the printed product should be extended appropriately to ensure that the ink is completely dry;

2 Ink contains excessive amounts of paraffin, silicon and other ingredients, should be replaced with ink or choose a more pre-coated film;

3 The ink used is a metal ink, and the pre-coated film should be selected;

4 The ink layer is thicker, and the thickness of the ink layer should be controlled during the printing process or the thickened precoat film should be selected;

5 The surface tension of the printed product is insufficient, below 36mN/m, the surface of the printed product should be surface treated before the film is coated to increase the surface tension to 38mN/m;

6 If there is too much dusting (anti-blocking) on ​​the surface of the printed product, the amount of dust should be appropriately reduced;

7 The water content of the paper is too high, and the water evaporates after the film is coated to separate the paper and the ink film. The water content of the paper should be adjusted to balance;

8 The film coating speed is fast, the pressure is small, and the temperature is low. The film temperature should be properly increased, the film pressure should be increased, and the film speed should be reduced.

9 The pre-coating film has a shelf life and should be replaced with a new pre-coated film.

Folding of coated products

Causes and solutions:

1 When the film is unwound, the tension control at both ends of the unwinding is unbalanced, and the wavy edge appears. The unwinding tension should be properly adjusted to balance;

2 The pressure between the heating roller and the rubber roller is uneven, which causes the unevenness of the film to wrinkle, and the pressure between the two should be properly adjusted;

3 If the pressure of the rubber roller is too large, the pre-coating film will be deformed, and the pressure of the rubber roller should be appropriately reduced;

4 The rubber roller surface is damaged and uneven, and the rubber roller should be replaced.