Coated adhesive is generally used in the field of printing, processing the surface of the printed matter, so as to improve the gloss of the printed matter, and play a certain protective effect on the printed matter, coated adhesive refers to the BOPP film on the paper of a kind of glue. Divided into oil-based laminating glue and water-based laminating glue, water-based laminating glue is widely used in China's printing enterprises. Properties of film adhesive The coating adhesive has the advantages of fast drying speed, high brightness, high peeling strength, strong adhesion, resistance to rolling line, smashing and embossing, and good adaptability to hot stamping, gold printing and silver printing. Widely used in book covers, packaging boxes, handbags, exquisite albums and other processing. Characteristic ● Cost-effective, simple process. ● Easy to use, fast film formation speed. ● Strong adhesion, wrinkle-free film. ● Good comprehensive performance, composite drying fast. The use of film adhesive process and precautions: 1.The way of laminating is dry laminating, which means that the laminating machine should use a dry laminating machine that can be heated by a drying channel and a composite roll. 2.The compound pressure is about 8-20 kg. The drying temperature is about 60-90 ℃. The temperature of the composite pressure roller is about 50-90 ℃. 3.If conditions permit, the glue is baked to seven to 90% dry is appropriate, in this condition, the product after the film is high brightness, stiffness and fastness. In order to prevent bubbles from appearing in the film, the temperature of the composite pressure roller needs to be reduced to below 50 ° C to prevent the glue from being squeezed out. The pressure should be reduced slightly.  4.In order to prevent the discoloration of gold card paper and ink, the glue should be completely dried. 5.When the glue is completely dried, the temperature of the composite pressure roller is as high as possible without burning the film, and the greater the pressure, the better.

In the process of die cutting, we often meet a variety of problems, the common is the burst line and dark line, then what is the cause of the burst line and dark line, and how to solve it? Here is a small series to give you the answer. "Burst line" means that because the pressure of die cutting indentation is too large, it exceeds the endurance limit of the paper fiber, so that the paper fiber is broken or partially broken; "Dark line" refers to the undeserved indentation line, which is generally caused by inappropriate selection of die cutting plate and indentation steel line, improper adjustment of die cutting pressure, poor paper quality, inconsistent direction of paper fiber and die cutting plate row knife, low water content of paper resulting in decreased flexibility and other reasons. Solution 1.Select the appropriate die cutting plate; 2.Proper adjustment of die cutting pressure; 3.The printed matter to be die-cut is placed in the workshop for a period of time before die-cutting; 4.Improve the relative humidity of the workshop environment 5.Reduce the tension on the paper In addition, there is a special case, that is, when die-cutting the hard box cigarette pack small box, because the distance between the indentation lines in many positions is very close, if the height of the indentation steel line is configured according to the normal situation, the tension on the paper is too large during molding, it will also cause "burst line". Therefore, we should try to reduce the tension on the paper, there are two methods: one is to reduce the height of the indentation steel wire; The second is to reduce the thickness of the indentation bottom die strip, but the two can not be used at the same time, otherwise the indentation effect is not very good. The best way is to reduce the height of the indentation steel wire, the height of the reduction is usually 0.1 ~ 0.2mm, the specific according to the paper quantitative determination, quantitative in 350g/m2 above the paper need to reduce the height of the indentation steel wire is 0.2mm, quantitative in 350g/m2 below the paper should be reduced by 0.1mm.

There are many factors affecting the quality of the film, in addition to paper, ink layer, film, adhesive and so on In addition to the objective factors, it is also affected by subjective factors such as temperature, pressure, speed, and glue amount. If these factors are not handled well, various laminating quality problems will occur. There are snowflakes on the product 1.The amount of glue is too small: the amount of glue is too small, and snow spots will appear on the entire surface of the print. The amount of glue can be appropriately increased. 2.Inappropriate pressure: too much pressure on the pressure wheel will squeeze out the adhesive on the edge of the print, resulting in snowflake spots on the edge of the print; Snowflake spots can also appear if it is not compacted. The pressure can be adjusted appropriately. 3.Print powder spraying too much: print powder spraying too much, the compound appears loose pine flower white fog, encounter this situation, should be appropriate to increase the amount of glue, or in the coating before sweeping the print powder. 4.Pressure wheel pressure is too small: there are bubbles on the surface of the entire printing product because the pressure of the pressure wheel is too small, and the pressure of the pressure wheel can be appropriately increased. The coated product has wrinkles The main reasons for the wrinkling of the coated product are the imbalance of the film transmission spoke, the inconsistency of the tightness at both ends of the film or the wavy edge, the thickness of the rubber layer, or the uneven electric wheel and the rubber spoke at both ends, the pressure is inconsistent, and the linear speed is different. Measures can be taken to adjust the transfer wheel to the equilibrium state, increase the film, adjust the amount of glue and increase the temperature of the drying channel, adjust the position and process parameters of the electric heating wheel and rubber wheel, etc.

As a kind of widely used adhesive, coated adhesive has a variety of processes. Here are some of the common processes used: 1. Hot melt coating: hot melt coating is to place a layer of film on the surface of the print, and then through hot pressing the film and the print together.In this process, the laminating glue is heated to turn it into a liquid, which then forms a uniform coating between the print and the film. This method can make the surface of the printed matter smooth and bright, and has waterproof, wear-resistant, oil-proof and other properties. 2.Water-based coating: Water-based coating is an environmentally friendly coating process. It is achieved by coating a layer of water-based laminating glue, and then covering the film over the laminating glue. Because the water-based coating adhesive does not contain organic solvents, it has little pollution to the environment during use. 3.UV coating: UV coating is a coating process using ultraviolet curing technology. In this process, a layer of coated adhesive is first applied, and then ultraviolet light is used on its surface to cure the adhesive quickly. This method has the advantages of fast speed, stable quality, etc., and can also make the printed surface more durable and textured. In short, the use of coated adhesive process is mainly selected according to different application scenarios and use needs. In practical applications, we should combine materials, equipment and production process and other factors to choose the most suitable for their own film coating process to achieve the best results.