In the process of packaging and printing, it is sometimes necessary to add ink to the equipment. The order of inking should be from large to small, that is, the main color ink with a large proportion should be added first. Precautions For Ink Blending In Packaging Offset Printing
For the deployment of light ink, first put the diluent, and then gradually add dark ink to the diluent. There are two methods of mixing ink: mixing a small amount of ink by hand; A large amount of ink should be mixed mechanically.Precautions For Ink Blending In Packaging Offset Printing
The hiding power of ink refers to the ability of ink to cover the background color. The stronger the hiding power, the lower the transparency of the ink. Four color printing requires high transparency of ink, otherwise it will affect the color restoration effect of printed matter.Precautions For Ink Blending In Packaging Offset Printing
In printing, the adhesion of ink is adjusted according to the following factors:Precautions For Ink Blending In Packaging Offset Printing
① The surface strength of the paper. The surface strength of the paper is large, and the ink adhesion can be adjusted more; on the contrary, the adhesion should be adjusted less, otherwise the paper “drops powder”. Precautions For Ink Blending In Packaging Offset Printing
“Hair loss” is very serious, which seriously affects product quality and production efficiency, which is often the main motivation to adjust ink adhesion.Precautions For Ink Blending In Packaging Offset Printing
② Printing speed. When the speed is fast, the requirements for adhesive deployment are smaller, and vice versa. The faster the speed, the more prone to “roughening” and uneven ink transfer. It is necessary to reduce the adhesion to adapt to it.Precautions For Ink Blending In Packaging Offset Printing
③ Layout graphic structure. When printing halftone images, the most important thing is that the shape and area of the dot should be copied correctly, and the adhesion should be adjusted more. When printing field images, we want to get a uniform and thick field, and since there is no problem of dot increase, the adhesion should be adjusted less.Precautions For Ink Blending In Packaging Offset Printing
④ Workshop temperature. When the temperature increases, the cohesion of the ink will decrease, which is more prone to problems such as increased emulsification and dot increase rate. Precautions For Ink Blending In Packaging Offset Printing
When adjusting the ink, increase the adhesion of the ink in advance. On the contrary, reduce the adhesion of the ink.Precautions For Ink Blending In Packaging Offset Printing
In the production of packaging offset printing, the ink drying is too slow, and the most common disadvantage is that it is easy to get “dirty on the back”. In addition, if the drying speed of ink is too slow, the free penetration of binder will increase, which will lead to dull ink and lack of luster.Precautions For Ink Blending In Packaging Offset Printing
If the ink dries too fast, it is easy to form film on the surface of the ink during the printing process, which may affect the progress of production, and may also lead to ink crystallization and affect the subsequent ink printing of dry overprint.Precautions For Ink Blending In Packaging Offset Printing