Anyone who has ever direct printed 100% nylon or 100% polyester athletic uniforms readily admits to the challenges faced in completing the job correctly. Many printers have even resorted to thermoplastic die-cut numerals, transferring the numbers to the uniforms leaving only the team name and logo to the direct printing process. While this is an acceptable process in which to decorate the uniform it creates two extra stepsmatching the ink color to the color of the die cut numeral, and then the transferring of the numeral to the uniform. If this is the process you are using now, this paper will eliminate these last two steps by demonstrating the proper techniques to direct print 100% nylon and polyester uniforms correctly and make the challenges easier to overcome so printing athletic uniforms can become a profitable part of your business instead of a burden.
Determining Fabric ContentIs it nylon or polyester?
Before beginning production on any athletic uniform check the fabric content of the uniform. Just recently we spoke to a customer who printed athletic gold ink on twelve navy uniforms for a youth basketball team. Guess what, eight of the uniforms had a beautiful gold printed logo and number while the remaining four had turned a hideous, greenish gold color a few days later. Upon further inspection, when both uniforms were placed side by side under a bright light and inspected closely, you could see a slight shade variation in the navy fabric between the good and bad prints. Upon further inspection, the customer discovered that the four uniforms with the greenish-gold prints were 100% polyester and the dye had migrated through the ink film and turned the athletic gold print a greenish color.
Uniform manufacturers have turned to polyester because it is an extremely durable fabric which costs less than nylon. This customer just happened to the unlucky guy who received a shipment when the manufacturer was changing his fabric over from nylon to polyester. Having learned a lesson the hard way, this customer will be inspecting all fabric content labels from this moment forward. Also, when you read the bottom of our Technical Data Sheet where it says in bold, black letters-- "CAUTION, always test this product for curing, adhesion, crocking, opacity, dye migration and other specific requirements before using in production", it would behoove you to heed this warning. You are not printing a $2 t-shirt, you are printing a substrate which can cost between 10-$50 or even more. Ruin just one uniform and your profit is gone!
Choosing the inkAre these uniforms to be game worn or replica uniforms?
In order to determine what ink to use you must first determine if the uniforms are to be game worn or replica jerseys. Union manufactures two specific ink series, Athletic Gloss Series (for 100% nylon) and the Polyester Series (for 100% Polyester) that are specifically formulated for game worn athletic uniforms. These inks are made with special plasticizers, pigments, fillers, resins and dye blockers to give prints the gloss, opacity, color brightness, bleed resistance and durability characteristics needed to survive the pounding of a full season as well as surviving the numerous laundering to remove grass stains and perspiration. These inks are typically more expensive than regular plastisol inks. If you think you can get away with using general purpose inks just because they are youth uniforms for the local Pop Warner football team, please think again. Because of the budget restraints of small colleges, high schools and youth sports teams, these game worn uniforms sometimes have to survive several seasons. Inks are not the place to cut corners.
If you go anywhere in public you see fans sporting the logos of their favorite teams on what looks like the real uniform of that team. Unless it is the die-hard fan that has to have the same shirt that Greg Maddux wears when he pitches for the Braves, he or she is wearing what is called a replica jersey. Replica jerseys are exact copies of the uniforms worn by professional and college sports teams including styling, trim and logo color. However, the likeness stops at the look. Generally, these jerseys are not constructed of the same materials as game worn jerseys and do not command the same price. Many of these jerseys are constructed of 100% polyester which again, makes it important to check the fabric content prior to production. Because these jerseys are only worn to the store or ball game and do not have to survive a 162 game season, a regular high opacity or low bleed plastisol (again check fabric content) that provides good coverage and easy printability can be utilized with excellent results.
Do I need to add a catalyst to my ink?
The most misused additive in the screen printing industry is the nylon bonding agent (catalyst) printers add to help plastisol inks bond to nylon jackets. Nylon jackets are woven and have a slick finish leaving plastisol inks nowhere to bond unless catalysts are added to glue the ink to the slick surface. Even though uniforms are made of nylon, the difference is they are a knitted nylon. To illustrate this point, take a nylon uniform and hold it up to the light, what do you see? You see light coming through the different fibers that have been knitted together to form the uniform. Anytime you have a fabric where you can see the fibers the ink will surround the fibers and form a mechanical bond during the curing process without the aid of a catalyst.
Nylon uniforms normally pose no threat for dye migration. As long as your dryer is hot enough to reach the recommended cure temperature of the ink and low enough not to melt or scorch the fabric, everything will be ok..
Are there special screen making considerations?
Because of the thicker ink deposits needed to give uniforms the athletic print look and durability you will need to alter your screen making techniques. Uniform printers typically use mesh counts in the 83-110 range depending upon the color of the fabric. Dark uniforms, particularly polyester should be printed on 83 mesh count screens while white, light colored fabrics, nylon or polyester can be printed with 110 mesh count screens.
Since ink deposit is directly related to the emulsion thickness on the print side of the screen you may need to coat your screens an extra time on the print side (bottom). This extra coat will also increase your print sharpness. Use the following guidelines for this process:
High solids, one part emulsions (Photopolymers)- Put one coat on the print side, turn the screen over and put one coat on the squeegee side. If you not satisfied with ink film thickness using this technique let the emulsion dry completely and then put an additional coat of emulsion on the print side (bottom).
Dual cure emulsionsPut two coats on the print side, turn the screen over and put one coat on the squeegee side and let dry. Complete the process by coating the print side of the screen again.
Diazo emulsionsSame technique as dual cure emulsions except due to the lower viscosity of this type of emulsion a third coat may be necessary.
Remember, always dry your screens horizontally, print (bottom) side down. This allows gravity to pull the emulsion downward on the print side giving you the thicker coating you are trying to achieve.
Will I need a special press for printing uniforms?
Uniforms are generally printed on manual presses because of their relatively short runs so any manual press on the market today will suffice. However, if you are going to do this full time you may want to invest in a numbering machine. A numbering press contains a short and very wide screen (approximately 20" tall by 6 wide) and contains the numbers 0-9. The screen is held in a carriage that slides back and forth depending upon the number to be printed. Registration guides on the press help line up the number in the correct position on the uniform for both single and double digit numbers.
Another method used to print numbers is with paper or plastic number stencils where the numeral has been die cut from plastic, thick parchment paper or card stock.
In this process a regular screen is coated using the coating methods described earlier. For a 6" number, the screen maker will utilize a 10" square mask cut from rubylith or some other opaque medium and place this on the screen as the image. This leaves a blank open image area approximately 1" square in size around the actual number. The printer then places the uniform on the platen and positions the number stencil in the correct position on top of the jersey. The screen is then brought down over the number stencil, and with the numeral acting as the image prints the numeral upon the uniform. After printing, peel the stencil from the back of the screen and repeat this process on each uniform. For larger numbers such as 8", 10" or 12" a larger mask will be needed to compensate for the additional number height.
Even though paper stencils cannot be reused, there are plastic stencils available that may be cleaned and used repeatedly.
Is there a "Rule of Thumb" for the placement of logos and numerals on uniforms?
There is nothing worse than to see someone wearing a uniform where one half of the number is tucked into the uniform pants or a front logo on a ladys jersey printed too low. Equally as bad are numbers that inconsistent in placement. The following guidelines should be used for the positioning of logos and numbers:
Front Logo for crew neck uniforms and v-neck style jerseys-Logos should be place no more than 1 _" 2" below the neck seam properly centered. Extra caution should be taken for double digit numbers that contain the numeral one such as 21 or 12. The numeral one is considerably thinner than the second number and will throw the horizontal centering off. If a number is to be placed below the logo, place it a minimum of 1" below the logo. For large width logos make sure there is a 1" space between the edges of the logo and the sleeve seam especially on raglan sleeve jerseys. Drop the design down until you can achieve this 1" side clearance. If a logo goes below 2" down in order to achieve this side clearance consideration should be taken to reduce the size of the logo.
Back numbers- For numbers, place the number approximately 7" below the collar of the shirt for mens uniforms. For ladys uniforms place the number approximately 6" below the color trim of the shirt to compensate for the height difference between men and women. If names are to be used they are generally placed above the yokes on football jerseys, especially if the number is 10-12" inches in height. All names and numbers again should not be closer than one inch to the side seams of the sleeve or jersey and properly centered. Remember our little warning in the front logo placement about the numeral one. For names not placed above the yoke on football jerseys and for other sport uniforms such as soccer, volleyball, basketball etc. use the number placement guidelines and place the name approximately 1 _-2" above the number.
For placing numbers on both fronts and backs of jerseys some printers use a less than scientific approach to vertical placement. In this method they will draw an imaginary horizontal line across the jersey that connects the bottom of each armpit. Then determine the vertical center of the number and place the vertical center on this line.
Shorts- Logos should be placed 2 _" from the vertical seam and 1 _" above the bottom seam of the shorts.
Again, these are only guidelines for placement. Special consideration for the best aesthetic appeal will have to made using the printers and customers judgment for oversize numbers and logos.
Are there any special printing considerations when printing athletic uniforms?
Special consideration should be taken when printing light colors versus dark colors, mesh fabrics versus solid fabrics and nylon fabrics versus polyester fabrics.
One color numbers or logos should be double hit to ensure good coverage and accurate reproduction of the color. With a medium (70 durometer) squeegee make sure the first stroke pushes the ink down into the fabric (not through the fabric). This will give the ink a sufficient area to wrap around and adhere itself to the fibers and form a strong mechanical bond. The second stroke should be made so the ink is cleaned from the screen and lay on top of the first coat. Good athletic printers have developed a technique so the second coat lays on top of the first coat and does not push the first coat further into the fabric.
Two color numbers and logos should not only be double stroked but also flash cured between colors particularly on dark garments. Flash curing between colors will ensure that each color has the same finished look and also help increase opacity. The artwork for uniforms is generally "trapped" which means part of the second color overlaps or touches the first color to ensure proper registration. Follow the same guidelines as printing one color numbers or logos except flash cure between the first and second colors. If a white or other light colored ink is to be printed as the outline or on top of the darker color ink, an athletic ink with a non-migrating pigment must be utilized for the first color. Non-migrating pigments will not migrate up though the light color causing a shift in color of the top print.
For polyester uniforms a low bleed ink must be used on all colors except white or light colors and a print/flash/print technique should be used to form a good ink film thickness that will reproduce the color, resist bleeding and give the number or logo good durability.
An extra, extra special consideration has to be taken when printing micro-mesh (small holes), mesh jerseys (regular size holes) or "porthole mesh" (large holes) uniforms. Because of these holes, the ink will go onto the printing platen and will transfer onto the next uniform. If you do not want to clean the platens after every print, simply spray the platen lightly with a repositionable adhesive, place a sheet of card stock or newsprint large enough to cover the image area of the number or logo, spray the card stock or newsprint with adhesive, and then place the mesh jersey on the platen and print. Some printers will even flash the image before removing the garment to ensure it does not accidentally drag through any of the wet ink that has been left on the platen. Discard the card stock or newsprint after each print and replace. Even though this may sound like a major pain it is much more productive than cleaning your platen after each print.
Good athletic uniform printers have taken many years to perfect their printing techniques. Upon asking most uniform manufacturers will provide at a minimal cost sample pieces of material in order for your printers to practice and perfect their printing techniques prior to producing a job. Maybe Curt Warner can handle the pressure of throwing the winning touchdown pass at the end of a game but dont put the same pressure on an inexperienced printer by having him print an eighty dollar jersey without some training.
Are there special curing considerations for athletic uniform prints?
Most manufacturers recommend athletic inks be cured at a temperature range of 300° -320° F throughout the entire ink film. Even though these temperatures are the same as recommended for inks printed on tee shirts, extra caution must be taken. Because of the thicker ink deposits required and the different thickness of the uniform material you may need to increase the heat, slow the belt speed of your conveyor dryer or do a combination of both in order for the entire ink film to reach the recommended curing temperature.
If you have six feet or less of heating panels in your dryer, you may also need to run the uniforms through the dryer a second time. This will depend upon the thickness of the material. We have worked with customers who were left scratching their heads as to why white ink was washing off a four ply reversible practice jersey but was adhering to a single ply mesh jersey. It was simply because it was taking longer for the garment to reach the proper temperature before the ink could cure. A non-contact pyrometer was directed at the one ply mesh jersey and the temperature was easily reaching the proper cure temperature. However, when placed upon the four-ply jersey as it exited the dryer the print measured approximately 250° F. When the jersey was immediately put through again while it still retained much of the heat from the first time through the oven, the ink film easily measured the required cure temperature when measured.
Why is this? After all, isnt heat, heat? Even though this might seem to make common sense, the answer is a resounding no and other considerations such as fabric weight, construction, moisture content and color of both fabric and ink must be considered. A plastisol screen printing ink cannot reach its proper cure temperature until the fabric does so it takes longer for four layers of fabric to reach temperature than one layer of fabric. Also, dark fabrics and ink color will absorb heat and reach temperature faster than light colors.
A good analogy is heating two different sized houses during winter. If one house is 1500 square feet (regular tee shirt material and print) and the second house is 3000 square feet (athletic uniform material and print), and your goal is to bring each house to a comfortable living climate from 0 degrees, it will take a longer time to bring the 3000 square foot house to a comfortable temperature. The same holds true for athletic prints--thicker fabric and ink film thickness, more; thinner fabric and thinner ink film thickness--less.
Undercuring results in poor wash fastness on both polyester and nylon uniforms and causes dye migration on polyester uniforms. We recommend that printers monitor their dryer temperatures several times daily. This is important when printing uniforms, especially polyester as over heating the fabric can cause just as large a problem as undercuring the ink. Polyester dyes are very unstable and start moving and looking for a place to go somewhere over 270° F. Even though the dye blockers put in inks do a good job of keeping the dyes from penetrating through the ink film at 300° -320° , you substantially limit this ability at temperatures above 330° F. One major uniform manufacturer recommends checking the fabric temperature to ensure it does not go above 330° F. Because polyester dyes are unstable and overheating is such a problem, printers should test their curing temperatures so any 100% polyester garment cures the first time through the dryer.
A relatively easy to use and inexpensive measuring device is a small non-contact pyrometer that looks like a weapon from an early science fiction movie. It has a laser pointer to indicate the exact spot where the temperature sensor reads and when the laser is positioned on the ink film or fabric gives a very accurate reading of the temperature at that particular spot and time of the curing process.. These pyrometers started out in the $900 range but lately smaller versions have been selling in the $89-$159 range. Save just one job and the unit has more than paid for itself!
Athletic uniforms may not be the easiest substrates to print but they do not have to be a major difficulty either. By following a few, simple guidelines in order to develop the proper printing techniques, understanding fabric content, ink film thickness and curing parameters you can easily make the team that plays like a winner look like a winner while also developing a profitable niche in your marketplace at the same time.
Customer testing is required and should be mandatory with this product or any new product or process before running production. Union Ink Companys 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 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.