What is the difference between rotary screen and flat screen printing?
1. Commonalities and differences
Textile screen printing mesh. Pattern design, black and white color separation (positive film), generally adopt continuous shooting process photosensitive plate making, in addition to independent flower shape, mainly by manual operation, high technical requirements for workers, low work efficiency. The plate-making photosensitive material needs to be water-resistant.
Non-textile screen printing. The pattern is usually completed by photography or scanning. The color separation is mostly in four colors, and most of the printed patterns are independent. There is no printing process, and the photosensitive material is mostly solvent resistant.
2. Wire mesh material
It is the main material of screen printing. The silk screen weaved with silk has long been replaced by nylon mesh. Although nylon mesh has high strength, wear resistance and elasticity, it is susceptible to changes in temperature and humidity, and has greater flexibility. , affecting the accuracy of the plate, so when printing high-end products, polyester (polyester) wire mesh is commonly used. There are also wire mesh, such as nickel mesh for rotary screen printing and stainless steel wire for circuit boards. There are a wide variety of screen sizes, ranging from 36 to 90 inches wide and from 80-500 mesh per inch, depending on the application.
4. Differences in printing materials
Textile printing is generally based on dyes, especially on silk fabrics, and the corresponding dyes are used according to different fiber properties. The technical process and supporting equipment are relatively complicated, and the printing paste for printing is printed, which is called “aqueous ink”. Due to the practical needs, the color of textile screen printing must have a certain degree of fastness (not easy to fade), and its color change is large, so the slurry and color materials are generally sold and stored separately, and used as a printing when required. Pulp. There are also a number of special functional paint printing pastes, which are often not limited by the properties of the fabric fibers, so the screen printing of the coatings has a certain position.
Non-textile screen printing inks. These inks are almost all solvent-based. Its biggest feature is "speciality", which is what kind of ink is printed. Secondly, the color of the ink is mostly sold, such as four-color ink. There are also some special functional inks, such as foaming inks, bright inks, fluorescent inks, etc. In recent years, the variety of screen printing inks has been increasing and will not be reviewed.
5. Post-press processing
In the textile screen printing process, post-press processing is very important, and it must be fixed by high-temperature steaming or bake, so that the dye is combined with the textile fiber to ensure the color fastness. After fixing, it should be washed with water to remove the carrier in the printing paste and the unfixed dye to make the color brighter. Even if the coating process is used, it should be baked at a high temperature, but it can be washed without water. The post-processing of non-textile screen printing is generally simple, but it is also necessary to take some necessary treatments according to the quality requirements of printed products, such as photocuring of UV inks.
6. Advantages and disadvantages
The advantages and disadvantages of the rotary net
Advantages: easy to operate on flowers, adding pulp, low labor intensity, high output, and limited color limit. Disadvantages: It is not easy to print moiré, fine lines and fine patterns;
Advantages and disadvantages of the flat net
Advantages: large printing flexibility, less equipment investment, suitable for small batch and multi-variety production, the number of sets is not limited. Disadvantages: The labor intensity is relatively large, and the color after printing is relatively strong.