7 Points of Improving Silk Screen Printing Technique
With the widely using about acrylic products, the requests of acrylic processing are also more strict. It is not only a challenge, but also opportunity for acrylic products manufacturer. It is important for manufacturers to have more advanced technology for acrylic sheet silk-screen. Here are 7 points for improving silk-screen of acrylic sheet:
1. One of the basic requests for perfect picture is the quality of transparent positive film should be good, that is to say edge of dot should be neat and opaque. Color of separation film and print ink should be same color standard.
2. Put the positive film on acrylic sheet, then expose and put the finished halftone in positive film and parallel with image shaft. If it comes more, rotate the halftone into right or left until the more disappear, normal 7° rotate will be OK. The direction of mesh and crossing of screen mesh are easy to form more. Main color and darker color will easy to have the problem of more.
3. As for the four color printing, you should use same size and stable aluminum frames. All of the frames have to use same type and model. To help the colored screen remove the more, the tension of screen should be equal and four halftone of four colors also need to be same.
4. Grinding finished doctor blade is important for high-quality printing, the shore hardness of blade is about 70. Doctor Blade should adjust to 75°. If the angle of blade if too flat, pictures might be Blur; if the angle is too steep, pictures might be distorted.
5. Back blade can’t be installed too low, or the film will be in full of excess ink, print might be blur and dirty.
6. Halftone images with high-viscosity ink printing, the finer screen requires more concentrated color ink.
7. Using UV ink, Halftone image tonal range should preferably 5% to 80%, shore hardness of squeegee should be 75. To control the UV ink does not rub dirty when color overprint, recommended by the cyan, magenta, yellow and black color sequence for printing. When using UV inks, screen thickness not exceeding 5um.