The components of screen printing ink are mainly composed of pigment particles, resin, solvent and modifier. Although the main function of the pigment particles is to display color, the size and dispersion of the particles will have a certain effect on the rheological properties of the ink. The main function of the modifier is to improve certain rheological properties of the ink.

When in printing, the silk screen ink is squeezed through a layer of silk screen with graphics (holes), and the ink is printed on the object through the small holes in the screen to form an image. The number of holes per square inch determines the quality of the print and also affects the rheological properties of the ink. Before printing, the ink is laid flat on the screen and cannot be dropped through the mesh. This requires that the ink has a higher viscosity under the action of low shear force and does not flow under the action of gravity.

In printing, when the roller is pressed over the mesh, the ink is squeezed and passes through the mesh. In this way, the ink must be shear-thinning under the action of external force, and the original structure can be quickly restored under the action of canceling the external force, and the viscosity is high, so that the ink will not drop through the mesh.

When the roller passes through the mesh and make pressure to the ink, the ink will be distributed to the printed object in the form of ink dots according to the distribution of the holes on the mesh cloth. At this time, the time for the ink structure recovers is critical. If it is too short, it will cause shortcomings. If it is too long, it will cause scattered points. Both of these situations will cause a reduction in image clarity.