Which water colour is suitable to print on t-shirts?
We recommed the Modatex range for screen printing using a water based ink. These inks dry at room temperature, do not require a drying rack, and after 96 hours they develop an excellent adherence to the fabric (natural or mixed).
How do you obtain the best results with water based inks?
The water based inks are used to print with meshes with a maximum count of 77 threads/cm; normally, for medium coverings, 55 threads are used, and for printing covering cross-hatches on a dark support even 43 threads are used.
The covering of the water based inks it is not lower than the plastisol ones, but not higher either, and therefore the same precautions have to be used (print of the white cross-hatch under the whole stencil, retouch the white on the final white areas, etc.).
Because the water based ink tends to dry on the frame, one must use some expedients: on an automatic screen printing machine always use the "water print" option, which regulates the squeegee and the scraper, so that at the end of the cycle the stencil remains full of ink, instead of empy, as it normally happens. Use the squeegee in the same way with a manual screen printing machine. Mix the ink with the additive with a small percentage of retarder gel, which slows down the drying process but does not modify its viscosity.
Is there a relation between the number of threads of the mesh and the ink used for the print?
The number of threads of the frame strictly depends on the type of ink used. With water based inks such as the Modatex, which is frequently used as it does not need a drying rack, the meshes with a 55 thread/cm count are mostly used. One goes up to 34 and 43 for printing white covering cross-hatches, and then up to a maximum of 77 for very fine details
If plastisol inks are used, one can go up to a mesh count of 100 threads.
How do you print several colours on the same t-shirt?
Between colours, one can wet print, as long as not too much ink leaks through. A spray remover, sprayed under the frame, on the printing side, may help. For the wet on wet print to work, one needs a good off contact (the distance between the frame and the t-shirt) even of 3 mm. The squeegee has to be used with a not too hard presssure and at high speed. The tilt of the squeegee is also decisive; however, with hand screen printing it cannot be thoroughly accurate.
How do you print on a dark coloured t-shirt?
In order to obtain bright colours on dark fabrics, it is necessary to print using a white cross-hatch with a 43 mesh count, and then print the other colours on it. After the cross-hatch, one needs to let the colour dry before spreading the following ones.
This is Franco Ratto,