What are the main points of the film coating process after printing of BOPP synthetic paper?

The film coating process of BOPP synthetic paper after printing is an important link in the post-press processing, which aims to improve the protection and beauty of the printed matter. Here are a few key points of the process:

First, the choice of coating materials

BOPP film: As the most commonly used laminating material, BOPP film has good transparency, mechanical strength and chemical stability, suitable for laminating with BOPP synthetic paper.

Other materials: Although PET, PVC and other materials are also used in some fields, they are not widely used in the film coating of BOPP synthetic paper after printing due to their high cost or inferior material properties.

Second, the coating method

1. Dry coating:

Principle: The plastic film is coated with a layer of adhesive, and then dried by drying channel evaporation to remove the solvent in the adhesive, and then in the state of hot pressing and paper printed matter bond into a coated product.

Features: It is the most commonly used film coating method in China, suitable for mass production, with good film quality and low cost.

2. Pre-coated film:

Principle: The coating manufacturer directly purchases the pre-coated plastic film with adhesive, and when the film needs to be coated, the film is hot pressed together with the paper print on the coating equipment to complete the coating process.

Features: Eliminating the deployment of adhesives, coating and drying process, the whole film coating process is fast and environmentally friendly.

3. Paperless composite film coating:

Principle: Using the surface smoothness (surface tension) of the non-backing paper composite film itself to bond with the printed matter to complete the lamination.

Features: Low cost, is one of the most widely used coating methods.

Third, laminating process points

1. Temperature control:

The temperature needs to be strictly controlled during the laminating process to ensure that the adhesive can fully melt and firmly bond with the print, while avoiding excessive temperature resulting in deformation or burning of the print.

2. Pressure regulation:

The appropriate pressure can make the film closely fit with the printed matter and improve the film quality. Too little pressure may lead to weak bonding, and too much pressure may damage the print.

3. Speed matching:

The running speed of the laminating machine should match the conveying speed of the printed matter to ensure the continuity and stability of the laminating process.

4. Cleaning and maintenance:

Clean the laminating equipment regularly, keep it clean and tidy, and avoid dust, impurities, etc., affecting the quality of the laminating film.

5. Quality control:

After the coating, the quality of the product should be checked to ensure that the surface is clean, smooth, wrinkle-free, and non-foaming, and the paper-plastic bond is firm.

Fourth, precautions

When selecting the coating material and method, the specific needs and characteristics of the printed matter should be fully considered to ensure that the coating effect meets the expectations.

Operation procedures and safety regulations should be strictly observed during the film coating process to ensure the safety of personnel and equipment.

To sum up, the coating process of BOPP synthetic paper after printing involves a number of points and links, which requires careful operation and strict control to ensure the quality and effect of the coating.