Monday, October 5, 2009

Reclaiming a Screen


RECLAIMING A SCREEN:

The same screen can be used many times for different print jobs. Thorough removal of stencil material (inks, etc.) ensures that no residues are left on the screen which could impair subsequent adhesion of the next stencil, and effect future print quality. Follow these steps for reclaiming a screen:.

1) REMOVING TAPE AND INK

After you have removed all the tape and excess ink from the screen, you will need to clean the ink residues off the stencil. A few examples of different wash-ups are:

Water: For water based inks: following by 2000 Green for any difficult to remove ink remaining especially if it has dried in the screen.

2000 Green: A biodegradable cleaner made from nature's own ingredients. A safe and environmentally friendly wash-up for both plastisol and water based inks. Cleans up adhesives easily (great for T-shirt pallets)! Wipes clean with a damp cloth. Removes tar, grease, grime as well as many other inks and paints. Mineral Spirits: For plastisols. More toxic, less environmentally friendly and safe than 2000 Green.




Apply 2000 Green with spray bottle
Work in with a brush or sponge
Wash away with water
2) REMOVING STENCIL MATERIAL

The next step involves removing all traces of stencil material. For stencils such as Duracoat and Autosol emulsions, Capillex films, Novastar and Autocut Amber, you would use Screen Strip.

SCREEN STRIP:

This powder mixes with water, in the usual proportion of 100g to 10 litres of water, depending on the water-resistancy of the stencil. Duracoat, Autosol Fast, Autosol Plus Clear, Capillex XR will need a more concentrated solution of perhaps 100g to 5 litres of water.

Procedure:

Apply a small amount to both sides of the screen with a soft brush or cloth. After two to three minutes, the emulsion coating will have dissolved and the mesh can be washed with a strong spray of water. NEVER ALLOW SCREEN STRIP TO DRY IN THE SCREEN.

3) REMOVING STAINS OR GHOST IMAGES WITH AUTOHAZE

When the stencil has been removed, ink hazes or ghost images may still be apparent. These should be removed if they block the meshes when held up to the light. For this purpose, use Autohaze, an alkaline paste that provides a highly effective method of removing stubborn stains and the hardest residues of emulsion or ink from polyester meshes. Procedure: Apply Autohaze to both sides of a wet mesh with a brush. Cover the stained areas in a circular motion. Leave on the screen for 6 to 8 minutes. If left longer, the mesh could be damaged and start to rip. Rinse off with a gentle spray of water, followed by a stronger spray.

4) ROUGHENING THE MESH WITH AUTOPREP

It is necessary to roughen the mesh with Autoprep periodically, usually every fifth or sixth stencil. You may want to use Autoprep more frequently when utilizing Capillex films.

5) DEGREASING THE MESH WITH UNIVERSAL MESH PREP

The last and very necessary step to Screen Reclaiming. Always finish reclaiming with an application of Universal Mesh Prep.



Safety First!

Remember to always wear gloves, goggles, a particle mask and a protective smock or overcoat during stencil removal procedure to protect skin, lungs and eyes.

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