Insufficient or uneven amount of glue due to insufficient amount of glue produced by the white spot can be observed in the composite machine. In the dry composite process, the coated adhesive must be able to fill the bumps and bumps on the surface of the ink and film to avoid appearance defects such as obvious white spots. When the water-based adhesive dry composite is used to produce lightweight packaging products, the economic coating amount of water-based adhesive is 1.8 ~ 2.2g/m2, and the working concentration is 42% (the working concentration of different brands of water-based adhesive may vary), and the number of lines is 180 lines/inch, and the depth of the mesh hole is 32μm. Due to the large opening degree of the net hole on the roller, if the surface of the roller is worn, it will have a more obvious impact on the amount of glue. Therefore, in the dry composite process of water-based adhesives, the operator should often detect the actual amount of glue applied by the roller to avoid insufficient amount of glue applied due to excessive wear of the roller. In addition, the uniformity of the amount of water-based adhesive is also a very key factor, if the coating is not uniform, there will inevitably be a small amount of local glue, resulting in white spots. Therefore, we should pay special attention to the following two issues: ①The assembly of the scraper should be flat and straight, without distortion, and the Angle and pressure of the scraper should be adjusted appropriately to ensure uniform scraping effect;  ②During normal production, the scraper should keep the left and right strings to avoid the wear of the rubber roller in a fixed position. Because water-based adhesives are not like solvent-based adhesives, they can achieve a better leveling effect under the action of their own gravity and surface tension after coating, so when coating water-based adhesives, it is necessary to use a flattening roller to flatten the adhesive. The speed, pressure and surface cleanliness of the flattening roller are related to the leveling effect of the water-based adhesive, and the rotation direction of the flattening roller should be opposite to the compound direction, otherwise the flattening effect cannot be achieved, and the speed should be slightly higher than the compound speed. The leveling effect of the water-based adhesive is also affected by the surface tension of the coated film. Since the surface tension of the water-based adhesive is obviously higher than that of the solvent-based adhesive, the surface tension of the ink on the coated film is required to be not less than 38mN/m, otherwise the water-based adhesive will automatically shrink after coating and cannot be continuously formed. Therefore, the operator should pay attention to the detection of the surface tension of the coated film. In addition, if the surface of the coated film is not clean, adhering to substances with low surface tension, etc., it will reduce the leveling p...

1.Ink The three primary color inks have different degrees of color bias, which will affect the color bias of the whole picture to different degrees. However, a small amount of color bias can be corrected from the ink preparation. When printing to grasp the gray balance of the ink used, the same amount of yellow, product, green do not produce neutral gray, they produce lighter, more turbidity with brown gray, rather than the real gray. The reason is that the ink is not ideal absorption of color light (the spectral curve of the ink is not ideal), that is, caused by the used ink is not pure, in the actual ink CMYK space, to get the field gray, need to improve the amount of green ink. The excess cyan makes the other two colors cleaner, for example, 30% cyan, 2l % magenta, and 21% yellow mixed to produce 30% neutral gray, if 30% cyan, 30% magenta, and 30% yellow mixed to produce neutral gray will have a dark brown color. For a certain type of ink product, the CMY value of mixing gray is constant, that is, the gray balance ratio value of a certain ink is constant, and the gray balance of this ink can be measured, and the image can be corrected according to this balance, so that the image to be printed can accurately reproduce the color appearance after correction, so as to make up for the defects of this ink. 2.The paper itself It is the smoothness, absorption, whiteness and gloss of the paper that have a great influence on the reproduction of the tone and color of the print. Smoothness is divided into apparent smoothness and print smoothness. Apparent smoothness refers to the flatness of the paper surface, which depends on the surface topography of the paper and describes the structural characteristics of the paper surface. The paper with high apparent smoothness is conducive to ink covering and leveling, the ink film formed is glossy, and the order reproducibility of printed matter is good. The apparent smoothness of paper has a certain relationship with its gloss, and the paper with high apparent smoothness has a relatively high gloss. Printing smoothness refers to the flatness of the paper under the action of printing pressure in the printing mode that uses pressure to achieve ink transfer. Printing smoothness is the comprehensive effect of paper apparent smoothness and surface compressibility, which has a direct impact on the quality of printed matter, it determines the contact degree between the surface of the paper and the plate or the surface of the blanket at the moment of stamping, and is an important factor affecting whether the ink transfer is comprehensive and whether the text is clear. Paper absorption refers to the acceptability of the paper to the ink and the absorption capacity of the binder in the ink, which directly affects the penetration of the ink to the paper and the conjunctiva. Many printing failures are caused by the ink-absorbing capacity of the paper and the printing conditions used. The absorption capacity of the paper to t...

Many people think that the temperature of the primer baking (dry) of Teflon paint is not important, just bake it, in fact, this is a misunderstanding. If you usually encounter the following situations, please carefully bake the primer. For the primer coating of Teflon paint, we recommend a temperature of 150 ° C, after the workpiece reaches 150 ° C, bake for 5-10 minutes. I. If the temperature of Teflon primer is too low, such as baking below 100 ° C, the following situations may occur: 1. If the baking time is long enough, the moisture and cosolvent in the primer are basically volatilized, and then spray the top paint, this kind of situation generally will not cause too much problem. 2. If the baking temperature is not high enough and the time is not long enough, the moisture and co-solvent in the primer are not completely volatilized, and the various components in the top paint will penetrate into the primer, and the luster of the finished coating will be dull and yellow in the final baking, which we also call the bottom biting phenomenon. II.2Primer is too high temperature, such as baking 200℃ for a long time In this case, it can be understood that a part of the primer has been cross-linked and cured, and the top paint can not be fully penetrated into the primer, so the top paint can not be fully integrated with the primer, resulting in the poor bonding force between the top paint and the primer, which is often the customer in the process of use, the adhesion between the top paint and the primer is poor, the top paint falls off, and the primer does not fall off, as shown in the figure. Therefore, we recommend that the temperature of baking primer should not exceed 180 degrees. The following is the recommended construction process: A: Material handling First, the material (aluminum or stainless steel) with (360℃×30 minutes ~380℃×10 minutes) air burning or solvent cleaning for the first step of degreasing, the second step is the surface roughness, corundum sand 80#~120#, pressure 0.4~0.6mpa, sandblasting, roughness is (2.0~3.5)μm B, Teflon paint primer spraying Before using the bottom oil, it must be fully rolled evenly or slowly stirred with stirring blades (do not use shear blades to stir at high speed, otherwise it will destroy the structure of the paint, make the paint gelatinized and deteriorated), and the treated material (must be clean, dry, without any grease and pollution, it is strictly prohibited to touch the sand surface with your hand, otherwise it will seriously affect the adhesion, and even lead to peeling) should be laid flat. (1.0 ~ 1.5) mm Ф gun pressure transferred to the distance (0.2 ~ 0.3 mpa (20 ~ 30 cm, concentrate spray directly, use (140 ~ 160 ℃) x (5 ~ 8) minutes, table dry film thickness for 10 ~ 20 microns C, Teflon coating coating spraying The same oil must also be fully rolled or slowly stirred with stirring blades before use. The work piece that has been coated with the base oil can be cooled to bel...

Thermal spray Teflon can not only reduce product costs and improve production efficiency, but also can be used to directly solve problems on the product to improve product quality and increase sales. After being sprayed with Teflon, it has the following characteristics: 1.Slippability: PTFE spray film has a low coefficient of friction. When the load slides, the friction coefficient changes, but the value is only between 0.05 and 0.15. 2.Moisture resistance: The surface of the Teflon coating film is not stained with water and oil, and it is not easy to stick to the solution during production operation. If there is a small amount of dirt, it can be removed by simply wiping. Short downtime saves time and improves work efficiency. 3.Non-adhesive: Almost all substances do not bond with Teflon spray coating. Very thin films also show good non-adhesion properties. 4. Heat resistance: Teflon spray film has excellent heat and low temperature resistance. It can withstand high temperature to 300 ° C for a short time, generally can be used continuously between 240 ° C and 260 ° C, and has significant thermal stability, it can work at freezing temperatures without embrittlement, and does not melt at high temperatures. 5. Wear resistance: under high load, has excellent wear resistance. Under a certain load, it has the dual advantages of wear resistance and non-adhesion. 6.Corrosion resistance: Teflon spray is almost resistant to drug attack and can protect parts from any kind of chemical corrosion. Anhui Sinograce Chemical production types of Teflon coating, a variety of colors, cost-effective, according to customer needs to provide a variety of types of Teflon material spraying, a variety of colors, high sexual price of domestic PTFE Polytetrafluoroethylene, welcome new and old customers to call consulting business.