The screen printing business changes with the season. Different seasons bring different challenges and different demands from customers. To help you prepare your business for a successful summer, we’ve prepared our two-part Guide to Successful Summer Screen Printing. Our second blog in the series will focus on how the summer weather can affect your screen printing operations.
The first blog in our Guide to Successful Screen Printing series gave you advice on how to choose merchandise to attract customers during the summer months. Once you’re ready to print summer apparel and products, you’ll have to make some adjustments in your shop to maintain successful screen printing operations. The heat and humidity that comes in the summer can have a negative impact on your normal operations. Knowing how high temperatures and high humidity can impact your shop will help you to overcome summertime screen printing obstacles.
Where do you store your inks and screen printing chemicals? In the summer especially, storage matters. Even if the temperature in your shop is comfortable, if your inks and screen printing chemicals are stored in areas prone to collect heat, such as against exterior walls that get direct afternoon sun, on high shelves or in storage closets that are closed off from the rest of the shop’s air conditioning system, the heat could have an impact on the performance of your chemicals and inks. Screen printing chemicals will break down faster, becoming less effective, when they’re exposed to extreme heat. You know that high temperatures are what cause plastisol inks to cure; if they become too hot, they could begin to gel or solidify, rendering them impossible to use. To overcome summer storage problems, store your inks and chemicals in a cool, dark environment and keep an eye on them during the summer to make sure the storage area isn’t getting too warm during the peak heat of the day. Always thoroughly stir your inksbefore you use them to restore texture that might have been altered by summer heat.
Heat and humidity also can have an impact on your emulsion after you’ve applied it to your screens. When storing your screens during the summer, you need a cool, dry place, as emulsion can reabsorb moisture from the air. Extra moisture in the emulsion can affect its durability during washout and printing. It’s best to measure the humidity where you’re storing your screens; the humidity shouldn’t rise above 40 percent. If the humidity in your shop is prone to dramatic increases during the summer, you might need to consider using a dehumidifier. Another note about screens: In climates where summer temperatures can spike to extreme levels, you might need to schedule your screen exposure duties to early morning or evening, as high temperatures can make it impossible to washout your screens after exposure.
Heat can cause plastisol ink to become thinner than normal. If your shop is warmer than normal during the summer, you might notice that the viscosity of your plastisol ink changes. If your ink thins out dramatically enough, you might need to take steps to ensure that you still get an adequate ink deposit when printing on hot days, such as using a higher mesh count screen than you typically would for a project.
The temperature and the humidity in your screen printing shop during the summer months also will impact how you cure ink. If you’re working with cotton garments, particularly heavyweight shirts or thick sweatshirts, the cotton will pick up the moisture from the air in your shop. When you go to cure those garments, the water first evaporates out of the shirt before the ink can cure. That might require slowing the belt speed on your conveyor dryer to get ink to cure properly during the summer. It’s wise when working with cotton garments on humid summer days to test your curing time and temperature before your press run. On the flip side, the summer heat in your shop can cause problems with over-curing or scorching garments. If your shop heats up during the summer, the residual heat around your conveyor dryer can cause the dryer to get hotter faster, or even heat beyond the level you’re expecting it to. Carefully monitor your conveyor dryer’s temperature during the summer to avoid scorching, overheating or unexpected dye migration.
These are just some of the problems that can occur when screen printing in the summer heat and humidity. The problems you face will be affected by your climate; in some climates, heat might be more of an issue, while printers in other climates will have to work hard to overcome humidity. The best way to deal with summer’s heat and humidity is to control the heat and humidity in your screen printing shop to the best of your ability. On top of that, be aware of the issues summer weather can have in your shop, and do your best to deal with those challenges proactively.