Brief Introduction to Classification of Film Coating Technology in Packaging and Printing

The film is the product of the post-printing process of paper-based prints. The film is a plastic film coated with adhesive, and the paper print is heated and pressed together to form a paper-plastic product. After the film-covered prints have a thin and transparent plastic film on the surface, the surface is smoother and brighter. This not only improves the glossiness and fastness of the prints, but also prolongs the service life of the prints. At the same time, the plastic film is waterproof. Anti-fouling, wear-resisting, folding-resistant, chemical-resistant and other protective effects. If the film is covered with a transparent light film, the printed images of the film products are more vivid in color and more three-dimensional, which is particularly suitable for the packaging of products such as green foods, which can cause people's desire for appetite and consumption. If a matte film coating is used, the covered product will give the consumer a noble and elegant feeling. Therefore, the packaged printed product can significantly improve the grade and added value of product packaging. At present, common film-covered packaging products include cartons, cartons, handbags, fertilizer bags, seed bags, self-adhesive labels, and so on.

Film coating process classification

According to the different raw materials and equipment used, the coating process can be divided into coating film coating process and pre-coating film coating process. The film used in the film coating process is now coated. The adhesives used are generally of solvent type and emulsion type, and are used with the adhesive. The film used for the precoating film coating process is pre-coated, and the adhesive used is generally of the hot melt type and the solvent-evaporation type.

According to the process of coating the paper print, the coating process can be divided into three categories: dry coating method. Wet coating and pre-coating methods. The dry film coating method is currently the most commonly used film coating method in China. It is applied with a layer of adhesive on a plastic film, and then it is dried in a dry drying tunnel of a film laminator to remove the solvent from the adhesive, and then heated. Press-bonded paper products with paper products.

In the wet coating method, a layer of adhesive is coated on the surface of the plastic film, and under the condition that the adhesive is not dry, the film is adhered by a pressure roller and a paper print. Since the advent of the water laminating machine, the water-based laminating process has been popularized and applied. This has the advantages of simple operation, small amount of adhesive, and no organic solvent that destroys the environment. The lamination film has high strength, High grade, easy recycling and other characteristics are inseparable. At present, the coating process is increasingly favored by domestic packaging manufacturers and has been widely used in packaging such as gift boxes and handbags.

The pre-coating film method is a direct purchase of a plastic film coated with a binder by a film factory. When the film needs to be coated, the film is hot-pressed on the film-coating equipment together with the paper print to complete the film coating process. The pre-coating process began in the 1990s. By using special equipment, the hot melt adhesive or low-temperature resin is evenly coated on the film substrate according to the design, and the precoated film is obtained. The pre-coating method eliminates the preparation, coating, and drying of adhesives. The entire coating process can be completed in a few seconds. No pollution to the environment, no fire hazard, and no need for cleaning. Plastic equipment and so on. At present, the process has been used in the fields of medicine and food packaging.