How to determine Mesh / Thread Count: Different mesh sizes are used for different type applications in the screen printing process. Mesh size is measured by how many threads of mesh there are crossing per square inch. For an instance, a 110 mesh screen has 110 threads crossing per square inch. The higher the mesh count, the finer the threads and holes are in the screen. The size of the mesh has a great deal to do with how detailed your image is and how thick the ink you are using should be. If you have an image with extremely high detail, a lower mesh screen won’t hold the high detail. The fine lines or dots in the image will simply fall through the holes in the mesh not giving you a correct representation of what your image should be. Also if you are using a thinner ink, the ink will also flood through the larger holes and soak onto your shirt or substrate making your image blurry as the ink bleeds. On the other hand, if you are try to printing with thicker ink ( Such as- White) through too high of a mesh screen, barely any ink will print through the mesh. You will notice that different companies have different sizes available. If the mesh count is fairly close, such as the difference between 155 versus 156, 196 vs. 200 or 81 versus 86 the difference is so negligible and small that it will not matter in your final results anyway.
Since there are many variables involved in screen printing, we can’t tell you exactly what mesh sizes are used for what applications. However, we can give you a general outline of what sizes to use for certain types of printing. Your basic and most standard mesh sizes are 110 and 156. 110 mesh lays a fairly thick layer of ink down. It’s great for block text letters and larger spot color designs. It’s also the recommended mesh for white flash plates because many times you will only have to make one print impression which speeds up production time. A 156 mesh also lays down a little thicker layer of screen printing ink, but offers you some higher detail ability in your image due to the finer mesh. If you are printing with a little thinner viscosity colors of inks, you may want to use the 156 mesh—ensuring the correct amount of ink is passing through your screen. Lower mesh counts like 40-86 are used for shimmer and glitter inks. These inks have particles in them that will not pass through the typical mesh sizes. You need a lower mesh count with large holes in order for all the particles to pass through properly.
Our plastisol inks have finer particles in them so you could probably use an 86 mesh while glitter inks have much larger particles so using a 40 or 60 mesh screen is recommended. 200 and 230 mesh are used for finer detailed images and thinner inks. These mesh sizes can hold larger half tone dots, but are not recommended for four color process prints or fine detail half tone printing. Also graphic and solvent based silk screening inks that are much thinner should be used with these mesh sizes. Also if you would like a softer feel to the ink on your shirts you can print through these higher mesh counts which will allow less ink through the screen giving you a much softer feel. This can get tricky because many times a duller distressed look is wanted for the artwork, but if bright vibrant colors are desired ( Especially- White ) you will have a hard time getting the opacity thick enough using these higher meshes. 305 mesh is used for extremely high detail textile printing and fine half tone four color process and simulated process prints. Fine half tone dots need high, fine detail mesh in order to hold and expose on. Higher meshes such as 355, 380 and 400 are used mainly for graphic printing with UV inks. UV inks are extremely thin and (many times) are used for high detail printing on signs, banners or CD’s. Using a higher mesh allows the automatic presses used in UV printing to regulate the amount of ink passed through the screen.
White versus Dyed Mesh:
01. White mesh has more light refraction than a dyed mesh. In other words light will scatter on a white mesh causing a less resolute image.
02. White is usually used in lower mesh counts, up to 155 count, which typically are used, for spot color work or larger text.
03. Yellow or dyed mesh, has very little light refraction. In other words you get a much truer image thru screen, resulting in a more defined edge and a crisper printing. On counts above 155 you would typically use a dyed mesh.
04. One thing to keep in mind, is that a dyed mesh will have a bit longer exposure time than a white mesh, say almost 15-20%.
Screen Printing On Mesh Substrates:
Are there an easy way to printing these substrates? Well, not really, there is no quick solution and again there are many variables to consider. So let’s start by taking a look at the material! Typically most mesh substrates are made from Nylon or Polyester or a combination or both. Nylon will shrink and polyester will bleed when heated.
Let’s start with nylon and what you can do to minimize a catastrophe! Nylon does not like heat and will shrink when heated. I recommend to pre SHRINKING each garment before you take your project to the press or screen, simply run each garment through a conveyor dryer, and reduce the heat to around 270 degrees. If you use a flash heater raise the heater up to avoid burning the substrate.
Polyester is similar to nylon; a huge problem with this kind of fabric is the bleed factor. Polyester when heated will give off an invisible gas that will travel up through the layers of ink. You may have seen this on dark garments printed with light colors thru screen mesh. Commonly called sublimation or bleeding. The color of the printing can change after the print has been heat cured; the color of the garment will show through. For example if you print white on a red polyester garment the end result will be an off reddish white print. I recommend using a low bleed poly white to block out the sublimation or bleeding! Pls keep Note: you can add catalyst to low bleed polyester ink.
What kind of ink should be used? I recommended to use Nylon ink with a Catalyst binder. YOU MUST BE USED A CATALYST OTHERWISE THE INK WILL NOT BIND TO THE SURFACE OF THE SUBSTRATE FOR SURE.
Simply add in the catalyst 10% to 15% per volume to the nylon ink, make sure to let it stand for 30 minutes before you attempt to printing. The idea is to get the ink to start setting up, I will explain why as we go!
Screens, what mesh count? I recommend using a 110 to 156. The typical thought is to get the print thick as possible, not so for this process. We want to lay thin layers flashing in between! If the ink is to thick and you try to gel a thick layer, the holes will fill and the garment will start to shrink or even worse burn! So thin layers and quick flash times are going to work better. Remember the ink is catalyzed and it’s going to accelerate the cure times.
Next set up your screen just like you would normally do. Since these substrates have holes the ink is going to pool up inside the holes. Here is what I found that works for me.
Spray down the platen with a mist adhesive, then place a pellon ( test square ) over the top. We are going to use the test square to absorb the excess ink that find it’s way in between the mesh.
Next, spray more mist adhesive on the pellon and then place the garment over the pallet as you would any other garment, make sure the substrate is secure if it moves simply re-apply more mist adhesive.
OK, magic time! Add the ink into screen, I recommend to using a 70-durometer squeegee and use a 90-degree angle for the first layer with medium pressure on the stroke. We are looking to for a base layer only, it’s going to look very weak but that’s all right. If you have filled some of the holes don’t panic, they will remain somewhat wet. Swings the flash over, and flash for a very short time, keep an eye out for shrinkage!!! Remember the catalyst? It’s going to help speed up the cure time.
Now, lower the screen, look through the screen and see if the entire image still lines up, if no shrinkage has occurred proceed with the second layer, use the same technique as before. After you have the second layer on the substrate I always check for a smooth consistent layer, check to see if any of the holes are filled! PLS NOTE: if you are printing a dark color on a light substrate two layers should do, however if you are printing a light color on a dark garment thru mesh the process may require a third and final layer.
Now for the tricky part, the holes are going to start to fill in if they haven’t already. Simply continue with the third pass, remember straight up angle with minimum pressure.
OK, everything looks good but some of the holes are filled on screen, not to worry. There are several ways of getting the plugged holes out. Remember the test square? The ink should have attached itself to the test square hopefully.
Remove the garment from the bottom. I like to roll each side equally from the beginning or the bottom of the printing. Carefully pull upward from the bottom, the holes should break free from the mesh and remain on the test square. Keep in mind the holes on the test square are going to be semi wet. Do not drag the garment across that area it will smear on the opposite side, leaving you with lots of spot cleaning.
You still have some holes that are closed if they are not totally dried you can use compressed air to blow out the affected area or if they are closed send the garment down the dryer and remove the holes with a good set of tweezers. I recommend changing the test square for each screen printing.
For printing on mesh with a lining I would recommend using a jacket clamp. It would be pointless to use a spray adhesive on these types of garments, the backing would stick and the mesh would stick to the back of the screen during the print process. Follow the same procedure as mentioned above, please keep in mind that this type of printing may leave ink on the inside liner. Just a side note. These kinds of projects are some of the most challenging for any screen printing and it takes practice, so fear not with a little practice you to can be the master of athletic printed garments.