Eight, filling The concept of filling is rarely mentioned in the application of laminating glue, but can never be ignored.The surface of the paper inevitably exists in some depression. When compounding, if the depression in the paper cannot be fully filled, it will also cause the weak. (Excellent filling effect)                                                                                 (Poor filling effect) The main factors affecting the filling effect are as follows: 1) The glue is hard, and the rubber layer lacks the ability to deform 2) The amount of glue is small, and the amount of glue is not enough to fill the depression in the paper or the gap in the ink 3) The temperature and pressure of the pressure roller are low, so that the rubber layer cannot be fully deformed and infiltrated 4) Paper or ink pores are too thick. Nine, fish eyes Fish eye is a common problem in the process of covering. It is mainly manifested in the gap in the shape of the crater in the film during the glue layer during the upper glue process. Note: There are many types of holes, such as oil nests, shrinking holes, needle eyes and so on! But the main reason is the following. (Fish Eyes Phenomenon) The principle of fish eye is that the film or paper contains materials that are incompatible with glue during the film or paper. These materials are mainly various types of organic oils that are not compatible with water, including: organic solvents, lubricants, elimination, eliminates, eliminates, eliminates, eliminates, eliminates, eliminates, elimination, and elimination agents. Bubble. These types of materials are common raw materials for film -covered enterprises, which are easily mixed in glue during the production process. Other reasons for fish -eye problems are: 1) Film electro -dizziness has a leakage point or a thin film placement time causes a decrease in electricity value 2) Mix with other types or different brands of glue 3) The glue viscosity is thinner

Anti -deformation power Anti -deformation capacity refers to a certain deformation after the composite product is affected by external forces, and this deformation will produce a certain amount of elasticity, especially the thin film. If the combination of composite is not enough to resist the elasticity of the return, foaming will occur, etc. Happening. There are many processes that produce deformation, such as pressure lines, uneven, mold cutting, etc. The ability to resist deformation of glue is often contradictory with bonding performance, so why does it have contradictions? First look at this problem from the hard and hard relationship between glue. ■ Comparison of adhesive hard and hard performance By adjusting the types and ratio of raw materials in the formula of adhesive products, the glue can have different soft and hard characteristics. (Drawing effect diagram of soft and hard rubber layer) Generally speaking, the bonding properties of glue are affected by its hardness and softness. The glue is soft, it has high viscosity, but under the action of external force, it is easy to deform and draw wire, resulting in the fracture of the adhesive layer.The hard glue is not too deformation and fracture, but the bond strength decreases. So glue is looking for a suitable range between soft and hard.Soft glue has good initial viscosity, strong deformation and permeability, but low tensile strength, easy to break, so it is prone to problems in embossing and die cutting. The hard glue has high tensile strength, but poor viscosity, and the stripping strength will be weakened after the film is covered. The degree of softness and hardness of glue will be affected by temperature. When the temperature is higher in summer, the glue has soft characteristics, and when the temperature is lower in winter, it has hard characteristics. (Effect diagram of separation of film and adhesive layer) After understanding the relationship between the degree of soft and hard glue and the bonding force and the ability to resist deformation, we can carefully discuss the deformation of composite products. ■ Separate the film from the adhesive layer This situation shows that the glue and film have insufficient adhesion or soft glue. It seems that these two situations are a bit contradictory, and they are actually extreme phenomena in two situations. ★ Insufficient adhesion for glue and film We have talked about the reasons why the film and glue adhesion are insufficient. The main is the insufficient film, the presence of water, and the low environmental temperature causes the glue to be strong. ★ Glue is too soft If the glue is soft, it is easy to cause the glue layer to rose and break it. This situation is prone to occur in high temperatures in summer. The environmental temperature is high, and the performance of the rubber layer will be transferred to a soft direction. Therefore, this situation will occur if it is used in summer in summer. (Details of the separati...

Bond strength and deinking Bond strength is one of the most important indexes of glue properties. Bond strength refers to the amount of force required when the film and paper are stripped, and this index is often combined with the deinking effect. We first need to understand the principle and structure of paper-plastic composite. If you want to enhance the bonding force, you must consider the rationality of the bonding force of each layer. As can be seen from the figure below, the composite bonding force mainly includes: 1) Adhesion between ink and paper 2) Adhesion between adhesive layer and ink 3) Adhesion between film and adhesive layer Relationship between various peeling effects, adhesion, and deinking ▲Peel off completely from the paper and deink completely When completely deinking, there are often two situations, one requires a stronger peeling force, while the other is completely opposite, only a lower peeling force is required to completely deink, the main reason for these two different results is The reason is the difference of paper. 1. The peeling strength is high, which means that the bonding force of the other two layers is greater than the bonding force of ink and paper, and the effect is better. This is also the best composite effect pursued by most composite manufacturers. 2. The peeling strength is low. One reason is that the bonding force between ink and paper is poor, or the ink has false drying phenomenon. The more reason is that the surface of the paper is loose, which is especially common in the compounding of gray and white cardboard. The surface layer of gray-white cardboard has a lot of fillers. If the glue cannot completely penetrate the surface layer and combine with the slurry layer after compounding, it will occur on the surface layer during peeling, and the peeling force required at this time is very small. ▲The ink layer is disconnected, part of the ink is on the film, and part is left on the paper (Partial deinking schematic renderings) This peeling state should be the most ideal peeling effect, indicating that the bonding force of each layer is very good. But pay attention to the situation of gold and silver ink, the surface layer of gold and silver ink is very similar to gray and white cardboard, it is composed of copper powder or aluminum powder and some binders, its internal structure performance is not very good, the ink layer is relatively loose, peeling off It is easy to separate during the period, and the peeling force is very small. ▲The adhesive layer is separated from the ink layer without deinking This situation shows that the adhesion between the adhesive layer and the ink layer is insufficient and the effect is poor. There are several reasons for this situation: 1) The glue is very hard, especially the summer glue is used in winter. 2) The temperature and pressure of the pressure roller are not enough during compounding, so that the glue cannot fully deform and penetrate into the ...

Hot melt adhesive (English name: HotGlue) is a kind of plastic adhesive, in a certain temperature range, its physical state changes with the change of temperature, but the chemical properties remain the same, its non-toxic and tasteless, belongs to environmental protection chemical products.Because the product itself is solid, easy to package, transport, storage, no solvent, no pollution, non-toxic type; As well as simple production process, high added value, bonding strength, fast speed and other advantages are favored. Environmentally friendly water-based adhesive is environmentally friendly. Water-based coated adhesive is a way to process the surface of printed matter, improve the gloss and strength of the surface of printed matter, and enhance the aesthetic effect. To measure the quality of the film, it is also necessary to examine its brightness, strength, bonding force and so on. Waterborne wet laminating is characterized by its high strength, easy recovery, no pollution and so on. To this end, we launched our own water-based film adhesive! Definition and classification of laminating adhesives Laminating glue refers to PET, BOPP film composite on the paper of a kind of glue. In the post-press process of the printing and packaging industry, the film coating improves the brightness of the printed matter, enhances the water resistance, makes the ordinary paper have the advantages of film and paper, and provides a beautiful visual effect for the packaging. Laminating adhesive includes water and oil - based two. In the domestic now water-based coating adhesive, most of the water-based acrylic emulsion system. Classification of laminating adhesive 1. According to chemical properties 2. According to the composite process Wet composite and dry composite Wet composite although the machine covers a small area, less power consumption, simple operation, but the finished product of the composite toughness is poor, poor adaptability to gold and silver ink, high-grade products simply cannot meet the requirements, with the maturity and perfection of water-based dry coating adhesive, people are more and more like to use water-based adhesive dry composite. 3. According to the printing method Lithography and intaglio printing Lithography is characterized by ink printing on paper and glue coating on the corona side of the film. At present, paper - plastic composite is mainly offset printing. This kind of compound equipment is relatively simple, compound speed is slow, gluing amount is large. There are two ways of gluing on mirror roller and mesh roller. Gravure printing is mainly characterized by ink printed on the film, glue coated on the film ink side. This way is film and film composite, in the paper and film composite application ratio is not high, but some special paper will use this composite way, this kind of composite equipment is relatively complex, composite speed is fast, less glue, more use of mesh roller glue, glue amount can be adjusted according...