The glazing process is an important part of improving the practical value and quality of packaging and decorating products, trademark labels and cover books. Through glossing, the glossiness of printed products is increased, and the colors are more vivid and eye-catching, giving people a beautiful visual effect and doubling the value of the product.
The good results of the glazing process are obvious, but if you do not understand the factors that affect the quality of glazing, it will be difficult to guarantee the quality of glazing. Therefore, it is very beneficial to improve the quality of color printing products by correctly understanding several situations that affect the quality of glazing and then taking corresponding measures to overcome them.
First, the impact of temperature on the quality of the product coating
Under normal circumstances, the temperature of the printing product is controlled at about 20°C to obtain ideal results. However, if the coating is applied during the winter, the coating oil will be easily solidified due to the low temperature, which is not conducive to the normal flow of the coating oil, resulting in uneven oil film on the surface of the coated product, and thus the brightness of the product must be poor. In order to overcome the disadvantages caused by environmental conditions, the varnish should be placed in a relatively warm place. If the temperature of the coating oil is lower than 10°C, the coating oil should be moved to the room at 20°C for a day or more to maintain the fluidity required for the coating conditions. If necessary, the varnishes may be diluted with a solvent as appropriate to allow normal glazing.
Second, the paper properties on the quality of the coating
The process practice shows that the quality and characteristics of paper directly affect the quality of coating products. For example, due to the smooth surface of the coated paper, the gloss effect is significantly improved after coating. The surface of the whiteboard paper or offset paper is relatively rough, and the glazing effect is relatively poor, and the brightness is not significant enough. This is because the varnish is almost completely absorbed by the rough paper fibers. In order to make up for the defect that the paper is liable to absorb oil to make the prints less shiny, the case base material may be applied to the surface of the prints first, and then the coating may be applied, or two passes of oil may be used to increase the print quality. Brightness to ensure polish quality.
Third, the impact of printing ink on the quality of polishing products
If the heat resistance and acid resistance of the ink used in the coating product are poor, the print image will change color or cause wrinkle skin and other quality problems. Therefore, the glossy printing ink products should use acid, ester solvents and acid and alkali resistance. In addition, it is also required that the ink does not change color and the gloss is good over time, and has a strong adhesive printing effect on the paper so as to prevent the ink from being variably caused by the coating and affect the quality of the product.
Fourth, the crystallization of printed matter on the quality of the coating
If the printing plate product is left for a long time or the dry oil is added excessively in the base ink, the ink layer forms a crystallization phenomenon on the surface of the paper. In this way, the gloss oil is not attached to the ink layer, causing the oil layer to bloom and uneven. When this happens, just add 5% lactic acid to the varnishes and glazing after mixing. By applying the modified coating oil to the printed matter, the vitrified crystal film on the surface of the printed product can be destroyed, thereby achieving the requirement of uniformly adsorbing the coating oil and forming a glossy film on the ink layer.
As long as the above factors affecting the quality of glazing products are correctly understood, paying attention to every aspect in the actual production process can not only improve the production efficiency, but also effectively guarantee the glazing quality of printed products.
The good results of the glazing process are obvious, but if you do not understand the factors that affect the quality of glazing, it will be difficult to guarantee the quality of glazing. Therefore, it is very beneficial to improve the quality of color printing products by correctly understanding several situations that affect the quality of glazing and then taking corresponding measures to overcome them.
First, the impact of temperature on the quality of the product coating
Under normal circumstances, the temperature of the printing product is controlled at about 20°C to obtain ideal results. However, if the coating is applied during the winter, the coating oil will be easily solidified due to the low temperature, which is not conducive to the normal flow of the coating oil, resulting in uneven oil film on the surface of the coated product, and thus the brightness of the product must be poor. In order to overcome the disadvantages caused by environmental conditions, the varnish should be placed in a relatively warm place. If the temperature of the coating oil is lower than 10°C, the coating oil should be moved to the room at 20°C for a day or more to maintain the fluidity required for the coating conditions. If necessary, the varnishes may be diluted with a solvent as appropriate to allow normal glazing.
Second, the paper properties on the quality of the coating
The process practice shows that the quality and characteristics of paper directly affect the quality of coating products. For example, due to the smooth surface of the coated paper, the gloss effect is significantly improved after coating. The surface of the whiteboard paper or offset paper is relatively rough, and the glazing effect is relatively poor, and the brightness is not significant enough. This is because the varnish is almost completely absorbed by the rough paper fibers. In order to make up for the defect that the paper is liable to absorb oil to make the prints less shiny, the case base material may be applied to the surface of the prints first, and then the coating may be applied, or two passes of oil may be used to increase the print quality. Brightness to ensure polish quality.
Third, the impact of printing ink on the quality of polishing products
If the heat resistance and acid resistance of the ink used in the coating product are poor, the print image will change color or cause wrinkle skin and other quality problems. Therefore, the glossy printing ink products should use acid, ester solvents and acid and alkali resistance. In addition, it is also required that the ink does not change color and the gloss is good over time, and has a strong adhesive printing effect on the paper so as to prevent the ink from being variably caused by the coating and affect the quality of the product.
Fourth, the crystallization of printed matter on the quality of the coating
If the printing plate product is left for a long time or the dry oil is added excessively in the base ink, the ink layer forms a crystallization phenomenon on the surface of the paper. In this way, the gloss oil is not attached to the ink layer, causing the oil layer to bloom and uneven. When this happens, just add 5% lactic acid to the varnishes and glazing after mixing. By applying the modified coating oil to the printed matter, the vitrified crystal film on the surface of the printed product can be destroyed, thereby achieving the requirement of uniformly adsorbing the coating oil and forming a glossy film on the ink layer.
As long as the above factors affecting the quality of glazing products are correctly understood, paying attention to every aspect in the actual production process can not only improve the production efficiency, but also effectively guarantee the glazing quality of printed products.