 This article covers how to make spot color heat transfers and does not cover how to print 4-color process or simulated process color heat transfers. There are two general types of paper: This is also known as "French Paper" or "T-75" or "Trans- French" is available in 11 x 13 sheets and larger. The cost is approx. 6 to 8 cents per 11 x 13 sheet. It can be printed on either side and is fairly stable and will not shrink too much when printing multi-color designs. This paper is also call "soft-trans" and is designed for printing soft-hand "hot split" transfers. It has a longer shelf life than T-75 when using "hot split" plastisol ink. Most general plastisols make good cold-peel transfers although if you are going to make a hot-split transfer you will need a plastisol designed for this purpose. Some ink companies make one ink that will work as either a hot-split, cold peel, or direct print ink - all in one! High opacity (white and gold) ink designed for dark shirts does not make very good transfers because the ink will not re-melt properly. Artwork for transfers should not be too detailed. If there is a lot of detail in the artwork, try to put a "backing color" such as white behind the detailed area to hold this ink on the garment. If there is no backing color, it may be necessary to heavy the lines on the artwork. Heat transfer screens should be exposed WRONG READING. Although direct emulsion works fine for transfer screens, capillary action direct film is a much better stencil choice because it provides a thicker stencil (for a thicker ink deposit) and has better edge definition for a sharper print with less sawtoothing. If trying to expose a detailed transfer screen, the film positive should be WRONG READING EMULSION SIDE UP. Cold Peel - 94 - 125 (36 - 50cm) Monofilament Hot Peel - 86 - 160 (34 - 62cm) Monofilament Heat transfers are printed one-color at a time on either a standard press using spray adhesive to hold paper in place, or on a vacuum table. No, you can't print them wet-on-wet. The ink must be cured between printing. It is common to print all one color and then re- register the print and print all the second color, etc. Transfers should always be printed OFF CONTACT for best print quality. The most popular method of registration is using a 3-point registration system commonly used when printing decals, posters, etc. Simply tape three thin cardboard "stops" (two across the back and one on the side) to your printing or shirt board. Slip each piece of paper to be printed snugly up against these stops before making the print. For additional information on this talk with your local screen print supply company. A special "Powdered Adhesive" can be applied to the wet transfer ink prior to curing that will help hold the transfer on unusual surfaces such as nylon mesh (not jackets!) and baseball cap fronts. The powder is available in two grades - fine and coarse. For multi-color transfers use the fine powder and apply it after each color OR use the coarse powder and apply it to the last color only. The powder transfers are COLD PEEL ONLY and these transfers should not be used on t-shirts because the ink is not as stretchy. Powdered adhesive is available from most suppliers for approx. $10 per pound. One pound will coat 500 - 1000 11x13 transfer sheets. Plastisol ink on heat transfer paper MUST BE ONLY PARTIALLY CURED or "soft cured." Soft curing happens at around 220 degrees. The soft cure stage is just past the wet point. To find the proper temperature, use paper thermometers to get the proper belt speed or time under the curing unit. If you are not sure, find the point where the transfers come out "wet" and start slowing down the belt or increasing the time under the curing unit until you get just past the wet stage and the ink does not feel wet. Since transfers are printed one color at a time, the paper is subjected to a number of passes through the dryer. Paper will shrink when it is heated for the first time. This may cause registration problems on multi-color designs. To compensate for this problem, artwork should use heavy trapping around colors if possible. Try not to gang multiple designs on one sheet that fill up the entire sheet (the transfers along the outside edge of the paper will be more out of register than the inside transfers). The application times and temperatures are different for each type of transfer and are VERY important to achieving a quality impression!
HOT PEEL APPLICATION
POWDERED ADHESIVE COLD PEEL APPLICATION
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