When printing on flat or body glass, very particular requirements are put to the screen printing stencils. Self-evident, the copying material, part of that stencil, has to meet these requirements, too.
The emulsion used for printing on body glass must provide good chemical and mechanical resistance against the used printing inks/ pastes, such as solvent based, UV or thermoplastic inks, even when running long print runs. Since the image is being copied frequently nearly up to the stencil’s frame, the emulsion or the capillary film should be very flexible, never getting brittle under strong chemical stress or heat strain (e.g. when using aggressive solvents or under high temperatures when printing thermo-plastic inks).
When printing on flat glass for the automotive industry, solvent-based, conductive silver-pastes are used for window antennas or heating conductors. Ceramic solvent- and UV-pastes for printing frames on windows. The silver and ceramic particles are partly very coarse with an abrasive effect on the stencil during printing with the squeegee. Here, chemical and mechanical resistance is absolutely necessary. Furthermore, particularly high flexibility is required when printing over the edge of the glass screen.
KIWO developed an emulsion meeting with all these requirements: AZOCOL S 300. It is a high quality, dual-cure Diazo-emulsion on a good price/ performance level. AZOCOL S 300 is resistant against ceramic and organic solvent- and UV-based inks/ pastes and solvent based conductive silver pastes. Its high solids content facilitates the production of a quality stencils at very low efforts. Viscosity and rheology of the emulsion are suitable for the use from coarse to very fine mesh.
AZOCOL S 300 can be sensitized with different kinds of Diazo. For applications on flat glass, we recommend Diazo No. 1, for body glass Diazo Nr. 6.
AZOCOL S 300 is a product development initiated by life practice, therefore it combines many features required on the market. Please ask for samples to carry out your own tests. For further information and support, please contact our technical department.