It is recommended that you observe proper safety guidelines while using screen printing chemicals, and emulsions.Like most screen printers you may have found that you are always in search of the perfect liquid emulsion. With this handy screen printing guide, you too can get started on using your emulsions. 78 to remove ink and haze and stencil scum residues, if necessary. Rinse gently, then use a forceful spray of water. 5 on both sides of the screen.ĭo not let the stencil remover dry on the screen. 3 to remove oily ink and solvent residues. Degrease with Screen Degreaser Liquid No. Remove the ink with the solvent recommended by the ink manufacturer. Touchup Option 1: Use excess emulsion and re-expose the screen. Blot excess water from the printing side with unprinted newspaper stock.īlockout Option 1: Before drying and exposure, use excess emulsion from the coating step to cover the blockout area.īlockout Option 2: After exposure and washout, dry the screen. Rinse both sides with a gentle spray until no soft emulsion is left on the squeegee side, and no foam or bubbles remain. Then using a water power spray, wash out the printing side till the screen is clear. In order to remove emulsion one must wet both sides of the screen with a gentle spray of cold water. One of the most common screen printing problems is emulsion not washing out properly. ■ A print made from the stencil best duplicates test positive at the required level of resolution. ■ The squeegee side emulsion is hard and not slimy. ■ No outline of the positive or darkening of the emulsion color is observable if the exposure is increased. Take a Step Wedge Test to determine the optimum exposure. Multiply the selected exposure time by all relevant exposure variables and distance factors to obtain an Approximate Exposure Time. Select an exposure time from the Screen Printing Emulsion Exposure Table based on the type of light source you have and the coating method you use. Use a dehumidifier in the drying area, if possible. Under humid conditions, dry the coated screen with warm, filtered air, up to 104° F (40° C) in a stencil dryer. Let the multi-coated screens dry in a horizontal position with print side down at room temperature in a dust-free environment. Then, after drying the screen, apply two additional coats on the printing side, back to back. Dry the screen thoroughly in a stencil drying machine with print side facing downwards. After each coating, rotate the screen 180°. Method 2: Apply two coats on the printing side, then two coats on the squeegee side, without letting the other side to dry. Method 1: Apply one coat of emulsion on the printing side, then one coat on the squeegee side. You can choose from the below mentioned methods and you will never fail while coating emulsion on your screen: Emulsifying the screen is pretty easy if protocol is followed. “How to coat a screen with emulsion without wasting?” a common conundrum faced by most screen printers. For the record, write the date of sensitizing on the label of the emulsion container. Wait at least one hour for the bubbles in screen printing emulsion to disappear. Stir the mix with a clean, flat plastic tool until it is uniform in color. Next, pour the fully dissolved sensitizer into the emulsion. Wait for 15 minutes till the bubbles disperse. Add lukewarm water to the diazo sensitizer by filling the bottle up to the shoulder. Usually, screen printing emulsion is too thick. 33.įor a new mesh mechanical abrasion is advised as it increases the surface area of for a better mechanical bond of the stencil, and increasing printing run life cycle. 3 or dilute Screen Degreaser Concentrate No. A used mesh or surface treated mesh may be degreased using Ulano’s Screen Degreaser Liquid No. Better still, use Ulanogel 23 which combines abrasive and degreasing action and saves you time. It is important to observe instructions for the best results in screen printing.īegin the mesh preparation by using Microgrit No. THIS IS A SCREEN PRINTING GUIDE that provides step-by-step account of emulsion and exposure process which is important for every screen printer.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |