To a qualified high-definition screen template, select high-quality screen printing inks, and control the printing parameters during the entire screen printing process, etc. are described separately. This article is willing to introduce beginners to the door, with the silk screen counterparts to learn from each other skills, triggering the opinions of experts in the industry, and truly achieve the purpose.
Screen printing process
The template has four functional requirements:
A. The web template should be able to reproduce the manuscript highly B. The web template should have wear resistance, chemical resistance and printing rate. C. The web template determines the reduction of the ink volume and hue. D. The web template determines the pattern. Sharpness and accuracy
Therefore, when fabricating a stencil, whether or not a suitable and sophisticated screen can be selected will affect the thickness of the printed lines and the dot size, range, and shape of the stencil. It will also directly affect the tone reduction of the color prints and the finest lines and color images. The reproduction result.
1. The relationship between mesh size, wire diameter, color, etc. and fineness of screen prints
1.1 The reproduction of the smallest diameter and the finest line
Two important parameters of the screen:
M0-mesh opening: that is the distance between two adjacent meshes. Hole width
D- The diameter of the wire, that is, wire diameter or wire diameter
1.1. 1 The three types of hole width and wire diameter have a fine influence on the circular pattern:
A. When M0=d, the copyable dot diameter is at least (2M0+d)~2(M0+d) or 3d
B. When M0 >d, the diameter of the dot that can be copied is at least (M0+d)~(2M0+d) If the dot = diameter of the wire d, the dots cannot be copied. C. When M0<d, the diameter of the dot that can be copied At least 2 (M0+d) if the network = wire diameter d, it cannot be copied
1.1. 2 Width of reproduction line of screen (B)
Line width (B)=2d+MO
Take SEFAR high tension PET1000 screen as an example:
Example 1: 120-34YPW net The screen shows a yellow silk screen braided with 120 meshes or approximately 120 mesh filaments per cm length, a wire diameter of 34 M, and a hole width of 45 μm.
Calculation: Can print the thinnest line width B=2d+MO=2x34+45=115 M=0.115MM
The minimum diameter of printable dot: high light spot (MO+d) and dark spot (2MO+d)
Mo+d=445+34=79 = 0.079MM
2MO+d=2*45+34=124 = 0.124MM
Example 2: 180-23Y Pw, the screen d=23, MO=29U
The reproduction of the thinnest line width is 2*23+29=70
Screen printing minimum dot diameter: 29+23=52 and 2*29+23=81 M and 180-27Y Pm mesh with d=27, Mo=22
Reproduce the thinnest line width 2*27+22=76
Minimum printable dot diameter from 2(MO+d)=2(22+27)=98 (dark tone point) to 2MO+d=2*22+27=71 (highlight dot)
Thus, in the screen with the same number of meshes, if the finer the screen wire diameter, the greater the opening MO, the more fine-grained printing effect can be achieved, and therefore, the minimum printable dot diameter depends on the selected The ratio of the wire diameter d of the wire mesh to the size of the opening (MO).
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