This technique is used for printing images or graphic models on different items as t-shirts, jackets, hats, etc. and on the most different materials as paper, plastics, textiles or metals. What makes the difference every time, depending on the specific base, is not the process but the ink. The first rule of silk screen is that the base material has to be plane.
The process is simple and consists in applying on the base material a layer of ink through a mesh. The printing can be done in one or more colors manually, automatic or semi-automatic. Polychromatic image can be done only on white materials and involves achieving color combinations by optical mixing the basic colors CMYK.
For darker materials the image is separated in more specific colors (up to 10 colors) with a basic white layer. These brighter colors give sharpness to the image.
For printing on textiles the restrictions are:
COLOURS: custom-colours, hks, pantone, cmyk
PRINT COLOURS: max-10