For coarse halftones of 50 lines/in. or below, conventional litho angles (Y = 0°, C = 15°, M = 75°, K = 45°) will work if the mesh is a plain weave of 355 thread/in. or more. The dots are large enough that the angular interference of the mesh with the halftone structure is not too much of a problem.
But as the line count gets higher (smaller dots), we must rotate the entire angle set away from the traditional litho angles, primarily because the angles for the yellow and black dots correspond exactly with the weave of the screen mesh and are likely to cause moiré. [...]
The most common corrected angle set for screen printing is Y = 7.5°, C = 22.5°, M = 82.5°, and K = 52.5°. These values will work for 95% of all screen-printing applications, even with the very fine line counts used by CD decorators. Also note that by using mesh with a lower thread diameter and plain weave, your chances of success increase substantially.