Caviar bead printing, the process of printing a clear plastisol that serves as an adhesive directly upon a garment or underbase and sprinkling soft, tiny plastic beads (caviar beads) onto the adhesive, is one of the hottest decorating techniques to hit the textile screen printing industry. Caviar beads come in many shapes and sizes to produce many different effects. Printers all over the world are finding this technique garners higher profit margins while only requiring slightly more effort than other special effects printing. This paper will define the techniques needed so any printer can learn to successfully do Caviar Bead Printing.
What Supplies Do I Need For Caviar Bead Printing?
Union’s Caviar Beads Special Effects Kit comes complete with every item a printer requires for caviar bead printing. The kit contains four sheets of 250 micron thick film to prepare the stencil, one quart of adhering liquid to adhere the thick film to the screen to produce the stencil, one pound each of black, clear and colored caviar beads, one quart of Union’s Caviar Bead Adhesive (PLAD-9160), and 4 sheets of colored transfer foil for extreme special effects.
How Do I Prepare The Artwork?
It is recommended printers do not use artwork with lines or images that are smaller than the size of two beads. This will insure that the bead makes as optimal surface contact with the Caviar Bead Adhesive to achieve the best adhesion and durability. Also, because you are exposing a thicker capillary film (250 micron), make sure you use a film or vellum that provides you with the densest image possible.
What Type Of Ink Is Needed?
Union has specially formulated a clear plastisol called Caviar Bead Adhesive that serves as the adhesive for this process. This adhesive has the proper mixture of components as well as a unique printing viscosity to insure the best adhesion of the beads. The thicker viscosity allows the adhesive to sit upon top of the fabric and provide a larger surface area in which to adhere the beads.
Do I Need To Add A Catalyst To My Adhesive?
No, Union’s Caviar Bead Adhesive is formulated to be used straight from the container.
How Do I Prepare The Screens?
Utilize an 83-110 (34-43 metric) mesh count screen that has been properly stretched to the manufacturer’s tensioning recommendations, thoroughly degrease both sides of the mesh with the proper degreaser and rinse and dry thoroughly. Prepare the film adhering emulsion included in your kit by using one part water and two parts emulsion. Cut your film approximately 1—2” larger than your design and remove the protective cover sheet from the film. Apply a piece of cellophane tape or masking tape to the side of the film which has a duller appearance and gently pull the plastic sheet away from the film.
Next, lay the film on a smooth, clean table making sure the side you peeled the protective sheet from faces up. Lay your screen print side down on top of the film and inspect to make sure the film is making complete contact with the screen. If screen and film are not making complete contact a build-up board must be utilized. The build-up board must be smaller than the inside diameter of the screen frame and at least 2-3” larger than the sheet of film. It should have a smooth surface and be made of plastic or acrylic. With the mesh resting on the film, apply a bead of the adhering liquid just above the top edge of the film, take a clean, 70 (medium) durometer squeegee with a slightly rounded edge and do three back and forth strokes across the film. Inspect the film again for good adhesion to the screen. Dry the screen horizontally, film side down. After the film is completely dry, peel the remaining protective sheet from the film. You will know the film is dry when the second protective sheet peels from the film without resistance. If you feel any resistance allow the screen to dry longer. With a scoop coater, apply an additonal coat of emulsion on the squeegee side of the frame to give the film extra adhesion to the screen as well as blocking out the large open areas surrounding the film.
How Do I Expose And Develop The Screen?
Place the emulsion side of the film positive against the print side of the screen and secure into place. Place the screen into the exposure unit and expose for approximately three minutes and forty-five seconds with a 5KW Metal Halide lamp set 40” from the frame. Because the intensity of exposure lamps fade over time use this is a guideline only. If your exposure unit contains an older lamp or if using a different intensity bulb or type of exposure unit, an exposure test must be initiated to determine the proper exposure time for your stencil. Contact your film manufacturer for the proper tools and advice for determining exposure times.
After the film has been exposed, wet both sides of the screen gently and begin washing out the image from the print side of the screen with a high pressure washer. Continue until the image is fully open. A typical washout usually takes 2-4 minutes but will vary with thinner or thicker films. If the film washes out completely, or if part or all of the image falls apart, increase exposure time. For images that do not wash out at all, decrease exposure time.
What Are The Printing Techniques?
The goal in printing the Caviar Bead Adhesive is to leave enough adhesive on top of the garment to surround the bead and provide excellent adhesion but not to put down so much adhesive that it takes away from the aesthetic appeal of the print. Place the screen into your press and set the off-contact distance between the screen and platen so that the screen peels from the garment approximately 1—2 inches behind the squeegee stroke.
After the off-contact distance has been set, make a test print to determine the proper squeegee pressure. Inspect the print to determine if the adhesive is sitting on top of the fabric or is being pushed into the fabric. Also, look at the platen after you remove the test print. Any residual adhesive seen on the platen is another indication of too much squeegee pressure. On automatic presses back off the squeegee pressure until the image does not print and then readjust the pressure until the adhesive completely clears the screen mesh and sits on top of the garment. Manual printers will have to develop a consistent feel for this technique. If you find that your technique does not allow the adhesive to sit on top of the fabric print a plastisol underbase, flash, and print the adhesive on top of the plastisol underbase. This method insures that the bead will be surrounded by the adhesive and provides the best durability during washing and wearing.
Prior to the print stroke, a good, thick flood coat is recommended.
How Are The Beads Applied?
After the adhesive is printed, remove the shirt from the platen and place print side down into a tray containing the caviar beads. From the back side of the shirt take a paint roller and with moderate pressure roll back and forth. This insures the beads are pushed into the adhesive. Lift the shirt from the tray, shake off the excess beads and put through the dryer.
Another method to insure the beads are pushed evenly into the adhesive is to use a blind screen. This is a coated screen that has been exposed completely without using any artwork to create an image. This method requires that the garment be left on the platen after the adhesive has been printed. The beads are then sprinkled onto the image by hand. The blind screen, which has some clear base in it to make it easier for the squeegee to travel across the print, is then brought down on top of the beads where a squeege stroke is made to push the beads into the adhesive.
Again, lift the shirt from the platen and shake off the excess beads and place in the oven.
Are There Special Curing Considerations?
Yes, because of the thickness of the adhesive and the caviar beads special curing precautions should be taken. Increased dryer temperature, slower belt speeds or a combination of both may be needed to cure the print. Caution: Improper curing may cause poor adhesion and washability of the finished print. Always test this product for both cure and proper adhesion before beginning a production run.
Are There Other Special Effects That Can Be Created With Caviar Beads?
Yes, there are many different effects you can create with caviar beads. The simplest effect is to print the adhesive directly onto the fabric and sprinkle clear or colored beads onto the surface to create a complimentary or contrasting effect.
You may also print a regular single or multi-colored design with plastisol, flash, print the Caviar Bead Adhesive and sprinkle clear beads on the adhesive. The colored print will show through the clear beads adding an extra dimension to the design.
A similar effect can be achieved for a single color design by adding 10% of a plastisol color to the Caviar Bead Adhesive. It can then be printed directly onto the garment prior to the application of the clear beads.
Another special effect many printers are achieving involves colored foils. After the beads have been applied and the print properly cured, slip the garment onto the platen of a heat transfer press. Take two flat pieces of wood
(tongue depressers or popsicle type sticks work great for this application) and place them approximately 1-2” from each side of the design. The sticks prevent the transfer press from flattening and melting the beads into one solid area losing the special effect entirely.
Next, place a piece of foil over the print and with light pressure, transfer the foil at 350° F. for approximately 3-7 seconds. Raise the transfer head immediately and allow to cool before pulling the foil from the design. Because the beads are the same material as plastisol ink (PVC) the foil will stick to the beads giving the design a bright, shiny appearance. With the correct pressure and time on the transfer press the foil will only adhere to the top of the beads.
Customer testing is required and should be mandatory with this product or any new product or process before beginning production. Our technical advice and recommendations given verbally, in writing, or by trials are believed to be correct. They are not binding also with regard to the possible rights of third parties and do not exempt you from your task of examining the suitability of our products for the intended use. We cannot accept any responsibility for application and processing methods which are beyond our control, nor can we accept responsibility for misuse by you of the products or use by you of the products outside the specified written instructions given with the products. Union Ink Company will replace or refund any defective product returned to us within 1 year of the date of purchase. This warranty is in lieu of any implied warranty of merchantability or fitness, and no other warranty shall apply. The user is responsible to determine whether the product is suitable for each particular substrate and application. The user must test thoroughly (including wash and storage tests) before using in production. In no event will Union Ink Company be responsible for indirect or consequential damages such as damaged substrates or printing labor.