How to Guide - Coating PLUS emulsions
How to coat ultra thick stencils with PLUS 9000
Ultra thick stencils are often required in textile printing to help deposit a high ink layer for special effects such as 3D printing, High Density Printing or suede leather effects. The key to creating these ultra thick stencils is to first choose a high solids, one pot emulsion such as PLUS 9000 as this will give the maximum build, for the minimum numbers of coats. PLUS 9000 is also photographically fast as it is very important that these ultra thick stencils are fully exposed.
One of the biggest problems is how to coat a thick emulsion layer but prevent it from sagging when it is wet. The secret to success is to 'skin' the emulsion on the print side to hold the emulsion as the thickness is built up.
The emulsion is 'skinned' by blowing a cold air fan onto the surface of the print side immediately after coating. This dries just the surface layer to form a skin.
The wet emulsion layer underneath can then be increased by applying additional wet coats to the squeegee side to create the ultra thick stencil.
A very coarse mesh is required, typically a 21 or 32/cm (51 - 81/inch) this has a large open area to create the maximum 'well volume' for the ink. Stencils of up to 300 microns can be produced without the need for intermediate drying.
Top Tips: (i) make sure the screens are thoroughly dried before exposure, (ii) do not under-expose the stencil and (iii) do not pre-soak the screen before washout as this will soften the emulsion, making it easier to damage when wet.
For more details on how to produce ultra thick stencils quickly and easily, please click on the video below
Stencils in excess of 300 microns are quite easy to produce with PLUS 9000 making it perfect for high build applications using Plastisol inks.