Full-water four-color ink application and technology

In recent years, textile printing using the principle of four-color separation has attracted attention. At present, the color patterns of popular textiles and handicrafts and cultural shirts on the market are all four-color printing.

The MD-994 water-based four-color ink produced by Shanghai Meide Fine Chemicals Co., Ltd. does not require additional equipment investment for the existing flat screen printing machine manufacturers. Just use the company's products and technical guidance (available on the website) to batch production. Produce printing products, and with the usual coating printing operation procedures and production speed.

MD-994 full-water four-color network special ink, colorful, easy to operate, cheap (only imported five to one-seventh color ink). For such a good product, to use it well, that is to create a four-color screen printing works similar to 98% of the original manuscript, there must be a set of excellent four-color screen printing process, which improves the electronic color version of the four-color network India effect is helpful. So, how do four-color dot printing?

Screen material selection

Wire mesh: Select a monofilament polyester yellow wire mesh of about 200-350 mesh. Because the white screen is exposed, light is refracted and the highlights of the pattern are lost. The elongation of the screen must be low. In order to avoid the moire, it is best to select the number of screen meshes as 5-6 times the number of lines in the electrical patch.

Sensitive Adhesive: Use a high solid content, good resolution, and a double-durable diazo-resin photoreceptor with good webbing adhesion. This ensures that the highlights are not lost during exposure, resulting in high-resolution, high-resolution screens.

Screen production

Electrical fragmentation: The original document to be printed is submitted to the unit of the computer screen printing and color separation system for image scanning, layout design, and output until the output of negative film. Electrophoresis negative film is best to use 35-80 lines / inch, the photosensitive film on the positive side of the film. The number of dots used for electroplating the negative film should be based on the size of the printed product and the distance between the printed matter. General advertising production pays attention to far-sighted effects (more than 1 meter above the visual distance), and the number of selected dot lines is 35-40 lines/inch, and 200-300 mesh is preferred. Such as textile printing, handicraft printing, outlets should be higher, generally use 55,60,65,70,80,100 lines.

Stretch the net: Use the diagonal stretching method. Color dot angles are usually used: 90 degrees for the yellow, 75 degrees for the blue, 15 degrees for the red, and 45 degrees for the black. If the number of screen meshes exceeds 5-6 times the number of line points of the electric fragmentation, a straight-stretching method may also be used, so that it is possible to prevent the occurrence of a troublesome moire phenomenon in the four-color screen printing. The most important rule for stretch nets is that the screen tension in the four printing screens should be the same. If the tension is different, the stretching length of the screen during the printing process will be different, resulting in inaccurate overprinting.

Laminating sensitized adhesive: First, clean the four mesh frames with detergent or a clean mesh solution. After drying, use a sharp sizing device with a sharp edge. The width should be similar to the inside of the printing plate, and the force should be uniform. First apply the squeegee once, then turn the screen upside down and then apply the squeegee once. Apply the same method to the printing surface twice. The film thickness is preferably 20 μm. The sizing should not be too thick or the dots will spread easily. After the coating is finished, place the screen horizontally and dry it. The drying should not exceed 30 degrees Celsius. Then blow it with a fan. The working darkroom environment should be clean and dust-free.

Shaiban: when the printing plate is to close the glass below the film, the best choice for vacuum drying box, and the choice of printing plate float glass, can reduce the refraction, otherwise it will affect the screen resolution and resolution. It is best to use the correction box when sticking the film, first align 100% of the rules of the film, and reserve the backing on the edge of the correction box, which should be the same with the formal board printing backing, and fix it with transparent double-sided tape. With the screen, then put it on the table to expose it. When it comes to formal printing, the alignment is much less labor-saving.

Rinse development: Soak both sides of the screen with tap water, soften 1-2 minutes, and rinse the printed surface with a small high-pressure water gun. The pressure should not be too high during flushing until the screen reproduces the negative. Then rinse both sides of the screen with tap water until no softened photoresist residue remains. Dry the screen, repair the pinholes, and re-exposure them to increase the durability of the screen.

print

Printing machine: The flat screen printing machine is the most important hardware for improving the printing effect. For four-color screen printing, the flat screen printing machine with high alignment accuracy should be used. The printing platen must be flat.

Scraper: In order to obtain high-quality prints, a blade with a hardness of 70 degrees should be used. The surface of the printing squeegee is smoothed with a screeder and the edges are in a straight line profile. The effective squeegee angle is about 70 degrees. The pressure of the printing blade must be adjusted to the same.

Slurry: Select MD-994 four-color dot ink, the new product has good thixotropy, PH value of 7-8, with the addition of additives regulation: the original plasma diluting agent, the standard color species deepening agent, retarder, and the original Slurry, base paste.

Printing: The edition is yellow, blue, red and black. At the beginning of the edition, the black version is printed first, then the one-by-one version, and the four-color screen version is correctly aligned before printing.

Manual printing and machine printing: If it is a large-volume manual printing, four touch strengths should be used with more tacit operatives to try and print first. The printing platen must be flat. The special attention is that the net distance (ie the distance between the screen and the desk plate) should be controlled between 2-3mm. Special emphasis is that the speed of the blade printing also affects the printing effect. Therefore, the speed must be determined according to the fineness of the four-color screen printing pattern and the characteristics of the underlying color, moisture absorption, and surface structure of the substrate. Compared with the original color draft, all aspects of debugging are correct and then officially open.