This kind of emulsion is already sensitised and ready for use.
IMPORTANT: Please note that this is a highly sensitive photopolymer emulsion that needs to work in environments with dimmed or yellow light to prevent expose the screens.
The mesh must be free of dirt, dust, ink residues, emulsion and ghost image. In order to achieve a good screen, previously degrease the mesh on both sides with PREPAMASK or KAUSTIMASK S, and then rinse thoroughly with water in order to remove any degreaser rests remaining on the screen.
Depending on the kind of mesh, always start with 1 or 2 coats in both sides of the screen so as to fill all the mesh openings. Leave the emulsion dry completely in a temperature up to 40ºC.
In order to improve and to ensure a maximum quality of copy and mechanical resistance, we recommend finishing with wet-on-dry coats on the printing face to build up the emulsion coating to the desired thickness.
Repeat the process of drying and coating as times as necessary so as to achieve the thickness wanted.
Drying of the coated screen
Dry the screen in horizontal position with the surface side down, under absolute darkness or safelight conditions, with a temperature of 30º – 40ºC (86º – 104ºF), a relative humidity of 30% – 50% and a moderate airflow.
Temperature, relative humidity and airflow affect the drying time. The screen must be completely dried before exposure, that way we will achieve a higher resistance to ink and ink cleaners. Drying the screen at higher temperatures than recommended, or under different conditions than mentioned may lead to inconsistent results and varying resistance.
Expose the screen with a metal halogen lamp (recommended). Due to the many factors that determine the exposure time, we cannot give accurate times. The correct exposure time is the maximum time that achieves the optimum resolution; it must be determined by successive tests, with a step exposure or with an exposure calculator such as KOPIMASK CONTROL STRIP KS1.
Under-exposure is slimy on the squeegee side during developing. Over-exposure leads to a loss of detail. Correctly exposed screens withstand high tap water pressure during washout.
Developing and washout
Adjust the water temperature to lukewarm between 18ºC and 30ºC. Gently rinse the screen on both sides with water. After 1 or 2 minutes rinse thoroughly on both sides of the screen, with a higher tap water pressure, until the developing has finished successfully.
In order to improve resistance, post-exposure time ought to be 4 – 8 times the original exposure time, always after developing and drying.
Once the screen has post exposure to recuperate the screen is possible.
Hardening / Chemically
Once the screen is completely dried, apply FIXAPLAST on both faces with a sponge, and leave the screen dry in a horizontal position under a temperature of 40ºC, during 2 hours approx.. It could also be hardened under a temperature between 22 to 25ºC within 24 hours.
Once the screen is hardened to recuperate it could be impossible.
Touch-up / blockout
Only for water-based inks resistant screens, touch-up with BLOCODUR or lac two components
Decoating / emulsion removal
Possible only if the emulsion is no hardened.
Use emulsion removers such as SCREEN STRIP or SERI CERO GEL in order to remove the emulsion from the screen. Before removing the emulsion, make sure that the screen is completely free of ink using DISOLIX ECO or an ink residue cleaner.
If the screen has been chemically hardened with FIXAPLAST, its reclamation will be very difficult. STARGEL 350 could be used, although desired results cannot be ensured.
Ghost image removal
When under-exposed, the emulsion can cause haze or ghost image. To remove it, use KAUSTIMASK S, STARGEL 350 o ZERO GHOST. Mixing KAUSTIMASK S with DISOLIX GEL is also a very effective way of removing ink haze.