Production and prevention of ink layer burst in th

Production and prevention of ink layer burst line in the process of matte printing

matte printing is imitating metal etching printing, and the matte ink is printed on gold (silver) cardboard by wire printing process. On materials with strong mirror effect, such as self-adhesive or other paper plastic composites, the ink layer appears sandblasted after UV irradiation, making the printed matter produce metal matte effect and etching three-dimensional sense. Frosted prints have a strong sense of sand, beautiful, generous, elegant and luxurious. In recent years, they have occupied a considerable proportion in the field of high-end packaging and printing, such as cigarette labels, wine labels, cosmetics packaging and so on. However, because the etching ink layer is thick, rough and not resistant to folding and rubbing, the ink layer of beautifully printed products often bursts and fuzzes after die-cutting. Dust and other problems seriously affect the quality of finished products. Among them, the ink layer burst line problem is particularly headache. Some products' ink layer burst occurs after die cutting and embossing, some occur during packaging, and some even occur before die cutting after printing drying. Therefore, the relevant person in charge of the national development and Reform Commission of Mexico said that the layer explosion line is an urgent problem to be solved

reasons for ink layer burst

1. Ink film is thick and brittle

frosted ink particles are coarse, in which the diameter of additive particles is about 15 ~ 30 μ m. The thickness of ink layer after silk printing can reach 100 ~ 150 μ m. Moreover, the surface of the ink film is rough, and the printing material is non absorbent, so the ink has poor adhesion to it, so the ink film is thick. It is characterized by high brittleness, and it is easy to burst under high pressure

2. Improper drying after printing

when the frosted ink passes through the UV curing device after printing, the temperature of the illuminated surface is too high, the polymerization reaction continues, and the ink layer automatically bursts after curing

3. improper operation of die cutting indentation

the quality of die cutting indentation is the main factor affecting the appearance quality of cartons. Unreasonable selection and improper use of die-cutting knife and indentation steel wire are the main reasons for ink layer burst, such as dull die-cutting knife

4. improper handling of paper

improper handling of paper structure, before and during printing is also a factor that cannot be ignored. The paper is too poor or the water content of the paper is too low, which will increase the brittleness and reduce the toughness of the paper, and also cause the ink layer to burst. For example, if the paper has not been humidified or the semi-finished products are stored improperly, the water content of the paper is low. After high temperature and calendering, the paper becomes brittle, and it is easy to crack after being pressed

prevention of ink layer burst

1. Correctly design the frosted pattern

when designing, the frosted pattern should avoid the molding place of the packaging box as far as possible, and should be at least 2 ~ 3mm away from the indentation and die-cutting position, so as to avoid damaging the frosted ink during die-cutting, which is conducive to highlighting, and the waste plastic may be the first to impact the three-dimensional sense

2 the automatic protection device of the plugging force testing machine has the following points:. Select the appropriate frosting ink, reasonably control the ink layer thickness and UV curing temperature according to the drying method. First of all, it is necessary to ensure that the number of wire mesh and particle size adapt to each other. Mesh for general coarse sand, 200-250 mesh for medium sand, and 300-400 mesh for fine sand. Secondly, in the printing process, the viscosity of the ink is correctly selected according to the size of the ink particle size. The coarse sand is generally controlled at 2000 ± 100cps, the medium sand is controlled at 3000 ± 100cps, and the fine sand is controlled at 3500 soil 100cps. Add ink additives as little as possible, and select the appropriate UV lamp. The UV lamp power is recommended to be about 10kW. The UV curing equipment must be equipped with a cooling device. Generally, a large-diameter exhaust duct is used and a water cooling device is installed on the lamp, so as to avoid the thermal deformation and brittleness of the paper when the paper jam passes through the light curing device<4. Have good weather resistance/p>

3. Reasonably design and arrange the die-cutting process

the perfect shape of the carton comes from the correct die-cutting indentation. The nature of gold (silver) paperboard and frosted ink determines the complexity of die cutting and indentation process

4. Maintain appropriate temperature and humidity

the gold (silver) paperboard needs to be humidified before printing to stabilize its water content. During the storage of semi-finished products and die-cutting processing, attention should be paid to maintaining the constant temperature and humidity in the workshop to ensure that the paper has appropriate moisture content. The worse the quality of the base paper is, the drier the paperboard is, the higher the probability of bursting of the printed matter. In case of abnormal weather changes, the die-cutting processing time and the production of die-cutting knife plate should be adjusted in time. Die cutting should not be carried out when the paper and ink film are brittle--