How should the basic quality soft package enterprises of printed materials control?

There are numerous types of films available in the market, but the most commonly used ones for printing are BOPP, BOPA, PET, and LDPE. When it comes to printing, the surface treatment of the film is crucial. One of the key factors to consider is whether the nylon film is wet or not, and it's essential to test the surface tension of each film roll before starting the print process. The corona treatment effect is time-sensitive. If the treated surface is left for too long, the corona effect may degrade significantly, making it unsuitable for printing. This also helps prevent printing issues that might occur if the film is accidentally reversed. Additionally, after prolonged use, the corona pen may give inaccurate readings due to the evaporation of the testing liquid. It’s best to use Dyne test liquids that are properly mixed according to standard guidelines to ensure accuracy and reliability. Among all the films, PE (polyethylene) is especially important to monitor. Some PE films undergo corona treatment during the blowing process, but sometimes the treatment isn't sufficient due to excessive thickness or unevenness. Moreover, if too much slip agent or release material is added, the corona effect can be severely reduced. For 12μm PET films, if the corona effect is similar on both sides, it should be carefully identified to avoid back-side sticking problems in printed rolls. The general corona requirements for printed films are as follows: BOPP and PE should have a surface tension of at least 38 dynes, PET should be above 50 dynes, and BOPA should reach at least 52 dynes. Nylon films are particularly sensitive to moisture, which can greatly affect ink adhesion and composite strength. This often leads to difficulties in printing, poor ink transfer, especially in thin layers, and reduced adhesion. Other common issues include wrinkling, an uneven surface, and visible lines. When purchasing film, it's important to clearly communicate your specific usage requirements to the supplier. For example, BOFIA films come in different grades such as printing grade and composite grade. With the increasing variety of films, it's crucial to specify the exact type—like PET, BOPA, or BOPP—because suppliers may offer multiple grades, but not all will meet your needs. Always verify with the supplier to ensure the right product is selected for your application.

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Single Side Breast Pump

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