The glue-free laminating technology is a technological innovation

Laminating technology has experienced a history of about twenty years in China. It can make all kinds of paper with color printing increase the strength after being coated, produce a sense of weight and texture, and capture the "temperament" of color printing paper, and use this to make various bags, boxes, book covers, samples and other products . However, the usual coatings are all in the form of adhesive coatings, such as the use of solvent-based adhesives, water adhesives and hot melt adhesives (pre-coated on the film and hot pressed), etc., but the non-adhesive coatings are different from this.

First of all, it does not use the conventional biaxially oriented polypropylene film (OPP), but uses the high-pressure polyethylene blow molding as the main material of the PE film, that is because of its easy to obtain hot melt and plasticity. However, PE film is a material with weak van der Waals force. The waxy additive composition makes the surface appear a weak interface layer. Therefore, in the hot melt state at a lower temperature, its adhesion to paper is also smaller, so this makes this unmodified technology of little practical value. However, when we perform a special strong treatment on the side surface of the PE film, this situation will greatly change. When we use a glueless laminating machine to hot-melt the PE film on the color printing paper, its peel strength has been significantly improved. It can stand rubbing without foaming, it can stand the test of temperature of -20 ℃ ～ 120 ℃, and it can stand rolling, cutting and so on. During the glue-free laminating process, a layer of auxiliary material is placed between the heating roller and the PE film, and passes through the glue-free laminating machine together, and then the coated product is removed from the auxiliary material. Because the materials used are different, the same kind of PE film can make light film, matt or other effects. If we put a layer of auxiliary materials between the heat roller and the PE film to work at the same time, the product and auxiliary materials come out of the machine together, and the product is peeled off from the auxiliary materials, and the finished product is produced. Due to the different auxiliary materials, the same PE film can be used to make a variety of film products such as optical film, matte film, and laser film. And from the visual effect, it is almost indistinguishable from the OPP film with glue.

The glue-free film coating technology does not use glue, and its advantages are very obvious: it greatly reduces the cost; there is no harmful gas that is easy to volatilize and penetrate in the production, ensuring safety; it is easy to recycle and generates less waste; The thickness is small, and only a small pressure is required during operation. The glue-free film coating technology is a technological innovation for the existing PE film coating on the market.

Because it does not use glue, its cost reduction is extremely significant. Especially matt film and laser film. Generally reduce the cost in tens of percent or even higher. Second, its green safety. Because the cost of PE film is the packaging material of food, and without the use of glue, those harmful gases that are easy to volatilize and penetrate will not exist in the production process or the process of using the product. At the same time, after testing, the product will be separated from the paper in a 5% caustic soda solution at 80 ° C, and the film and paper will separate. The film will float up and the paper will sink, which is easy to recycle, so it is a kind of green. The product. Thirdly, because the adhesive layer is glued and baked until the initial drying, the adhesive layer is 0.002 ~ 0.003mm, so the powder on the printing paper will appear to be uncompressed, resulting in uncompacted fine "snow". View. But no glue coating will not, because the film used in this technology is 0.017 ~ 0.02mm thick, it becomes the glue of this thickness in the hot melt state, so only less than half the pressure can easily make it not " "Snowflake", so there is no need to powder.

In terms of application, in fact, as early as 20 years ago, there was a PE extrusion compound of web (gravure printing) on ​​the market, but the disadvantage of extrusion compounding is that the sheet paper cannot be compounded and sub-membrane and Laser film composite. Therefore, this technology is only a technological innovation to the existing PE coating on the market. Although it is an innovation, it has inherited and continued the film market.