Thirteen.Skinning There are two common skin phenomena: one is in the packaging bucket of glue surface skin, the other is in the glue tray surface skin. ■ The surface layer of glue in the packing bucket produces crusts 1)If the temperature of glue filtration packaging is too high, it is easy to form crust in the barrel when the temperature drops, which is common in high temperature in summer. Because the glue is cooled slowly, it is easy to occur if the goods are urgent and cannot be packed at the appropriate temperature. 2)The packaged glue will also produce crust if it is exposed to sunlight. ■ Produce crusts in the surface layer of glue on the glue tray 1)The glue tray has a dead Angle (such as the right-angle shape of the glue tray) during the glue rarely flow, the surface of the glue moisture will slowly volatilize, forming a film and crust. 2)The baking road has hot air blowing directly to the glue tray 3)The surface of more glue foam foam is very thin, easy to film. Fourteen.Foam Foam is also divided into bucket foam and glue foam two cases ■ In-barrel foam This situation is mainly due to the violent shaking in the process of handling foam, in addition to the infiltration of more water stirring will also produce more foam. ■ Slow out of the glue tray when there are more serious foam 1)Failure of the glue defoamer or insufficient measurement 2)the speed of the upper cots is too high and the mixing of the glue is too strong 3)The level of the rubber layer and the upper cots are in an inappropriate position, and a large amount of gas is brought into the upper cots when they rotate. 4)The glue viscosity is too high, and the glue foam wall is thick and not easy to burst. ■ More glue foam, the consequences are as follows: 1)Influence the speed of composite (laminating speed) 2)When the amount of glue is large, part of the foam is coated with the film, and the foam enters the baking channel before leveling after bursting, or enters the baking channel before bursting, and then dries and breaks to form empty points. After composite, the phenomenon like fisheye and pinhole is generated. 3)It is easy to produce glue crusts in the glue tray. In the way of dealing with more foam, the common way is to add defoaming agent, but we must pay attention to the type, quantity and stirring method of adding defoaming agent. If the operation is improper, it is easy to cause the phenomenon of fisheye and peeling force decline. Fifteen. paperhanging Simply speaking, pasting is the paper and paper bonded together, so that it has better strength and stiffness, such as cardboard boxes, corrugated boxes. The same kind of paper is called to mount, and there are all kinds of common hanging tags. At present, most pasting adhesives used for pasting have low solid content and contain more moisture. Because of the structure of the paper, there are a lot of capillary tubes in it. After pasting, due to capillary action, moisture is quickly absorbed by the paper and rises to the...

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 ...