Line marks, chromatic aberrations, nets and other issues linger, check your squeegee!
We are a big printing company in Shenzhen China . We offer all book publications, hardcover book printing, papercover book printing, hardcover notebook, sprial book printing, saddle stiching book printing, booklet printing,packaging box, calendars, all kinds of PVC, product brochures, notes, Children's book, stickers, all kinds of special paper color printing products, game cardand so on.
For more information please visit
http://www.joyful-printing.com. ENG only
http://www.joyful-printing.net
http://www.joyful-printing.org
email: info@joyful-printing.net
Although the squeegee is very inconspicuous, it has a crucial impact on product quality for high-precision ink color printing technology. The squeegee is not used well, which may cause defects such as line marks, chromatic aberrations, and netting on the surface of the printed matter. Therefore, understanding the working principle of the squeegee and how to use the squeegee correctly is crucial.
First, the choice of polyester plastic squeegee
The function of the squeegee is mainly to wipe off the excess ink on the surface of the anilox roller, which can better control the amount of ink transferred to the printing plate. At present, the common polyester plastic scraper has a width ranging from 25 mm to 70 mm, a thickness ranging from 0.5 mm to 2.0 mm, and a knife edge angle of 30° and 45°.
Before printing, the first thing to consider is the printing layout, which is a solid version, a line text version or a multi-color overprinted dot color printing.
A. If the anilox roll in the factory press is 280-380, you can choose a squeegee with a thickness of 1.5mm or 2.0mm and a knife edge angle of 45°. The reason is that the anilox roller of the low-wire line wears the squeegee faster, resulting in an increase in the amount of ink and a darker printing color. Selecting such a doctor blade will not affect the printing color change too much as the amount of ink increases as the blade wears during use.
B. If the anilox roll configuration in the factory press is 380-550 lines, the higher the number of lines of the anilox roll, the higher the effect on the ink scraping effect. At this time, a doctor blade having a thickness of 1.5 mm and a knife edge angle of 30° can be selected. The reason is that the surface of the anilox roller of the high-network wire has a good surface finish, and the selection of a 30-degree thin blade tip can effectively achieve the desired ink-scraping effect.
Second, the polyester plastic squeegee should pay attention to the details of the installation
1. Cut the length of the squeegee according to the length of the anilox roller
When replacing a new squeegee or sealing knives, it should be noted that the length after cutting should be slightly longer than the length of the anilox roller by 25px; otherwise, the length of the squeegee and the sealing knives are insufficient during the printing process. The ink leakage occurs when the ink at both ends of the roller is not wiped off.
2. Pay attention to the flatness of the squeegee when installing
When it is necessary to replace the new squeegee for the problem, the mounting screws should be locked from the middle to the both ends to ensure the smoothness of the squeegee. A more practical method is to hold the scraper inward with the thumb of one hand (note the glove) and use a wrench to lock the screw on the clamp plate.