Reasons and Treatments of Crystallization of Printing Inks

The book covers, product samples, and some packaging and decorating prints of color printing process are usually made of large prints for the substrate, and then they are color-coded and stacked-printed on the ground color plate, and if the technical and operational measures of such products are appropriate, The ink quality of the printed product is good, the degree of beauty is strong, and the artistic effect of the product is necessarily good. Conversely, if the technology is not properly controlled, and blindly increasing the thickness of the printing ink layer to meet the requirements of the Mexican beauty, it is very easy to produce printing chain failure, resulting in adverse consequences and may even result in waste products, which is worth our attention.
The crystallization of printed ink film is one of the common faults in the color printing process. The feature of this process failure is that the overprinting of the graphic ink on the base color surface causes the occurrence of hair growth, floating, or overprinting of the next color ink. The ills on the printing. The main reasons are as follows: excessive amount of dry oil, overprinting time interval is too long, so that due to the crystallization of the surface of the ink film at the time of overprinting, the stacked ink layer cannot be completely attached to the background ink. Another reason is due to the lack of abundant process experience for operators and lack of understanding of process technology, and the relationship between paper properties and ink layer thickness has not been dealt with. If the paper is poor in gloss, the printing pressure is uneven or there is a slight shortage, the printed proofs may look like the ink is too light, but by increasing the amount of ink, they compensate for the roller surface. The defect of local contact between the printed sheet and the printing plate has increased the aesthetic effect of the printed ink. However, the ink layer thus printed has local accumulation and unevenness, and the ink does not penetrate into the fibrous tissue of the paper well, so that false printing may easily occur during the overlap printing. Therefore, the printing process should be based on the quality of the paper, as far as possible to adjust the color of the ink underneath the appropriate darker, and print a thin layer of ink, which can better avoid the ink layer printing thick, dry oil consumption Excessive product caused by the ink crystal crystallization failure.
If the surface of the printed film is crystallized due to improper printing process, it is difficult to realize normal overprinting. When appropriate, appropriate processing can be performed according to different situations. The most convenient method is to wipe the surface of the primary color ink film with a cloth. In this way, the ink layer crystal surface is rubbed so that the oil layer is destroyed, thereby increasing the ink adsorption. It is also possible to add a caustic solution of the vector to the ink to make the ink thick and sticky, but not so much as to prevent side effects. The method is too smooth on the crystal surface of the background ink, the use of the effect of the ink plus some industrial soap tablets, the soap tablets into crushed pieces of crumbs with resin oil into a paste-like, and then added to the ink, stir, and should Pay attention to adding dry oil, otherwise, overprinting the ink layer will produce slow-drying adverse reactions. In the past, our factory had used this method to adjust the defective products of superposition ink and ink layer crystallization, and solved the ink film crystallization process failures of the tea box products of a single embossing process, resulting in better printing quality. improve.
To deal with the crystallization failure of the printed ink film layer, attention should also be paid to the control of the operation technique. That is, when printing the overlapping color layout, the printing pressure can be appropriately increased to increase the adhesion of the ink. For severely crystallized products, we can use a virgin oil or No. 0 varnish plus silicone oil mixture to imprint once, and then print a color-stacked layout. This unrelenting approach, although it adds an inconvenience to the process, it can be better. To ensure the quality of the prints, it is still worth doing. ("Haida Print Materials Offers and Foreign Edition")