Other than testing and choosing the right garment, proper pretreating is the second of two primary factors contributing to a quality print. It is common for decorators to look elsewhere when determining the cause of a less than acceptable image on the garment. More often than not, it is in fact the pretreating that is the true culprit.
By applying too little pretreatment to the garment, the image will appear dull and washed out. The pretreatment solution gives you a barrier for the water base ink to set upon. Curing will start as soon as the ink makes contact with the pretreatment on the garment. An application of too little pretreatment will result in the ink absorbing into the fabric.
Commonly when demonstrating pretreatment of shirts for customers who already do their own pretreatment, the comment will be, “Oh, I use way too much!” An excessive lay down of pretreat solution will result in a stiff feel to the fabric. Beyond this stiff square on the garment, too much pretreatment can result in ink washing out of the shirt as well. In this scenario, the ink cannot penetrate the thick barrier of pretreat solution to bond with the fabric. Water base ink not bound to the fabric will simply wash away in the first laundering.
While pretreat solution should wash out of the garment with the first laundering, a too heavy application will tend to remain in the shirt. In other words, the stiff square will remain as a permanent part of the garment. The solution is to back off on the amount of pretreat you apply until you find the perfect balance between quality image and amount of pretreatment applied.
More and more decorators are choosing the automatic pretreatment route. Cleanliness and consistency are the key factors. An enclosed pretreat machine can be used in the same room with your printer. And, each garment will be pretreated exactly the same as the one before.
With hand spraying using an electric paint sprayer, there is a tendency to spray just a little bit more than necessary. Plus, hand spraying will be a sticky, messy process.
There are other methods to apply pretreatment – paint rollers, pretreatment soaked papers, pump spray bottles – but pretreat machines and power sprayers are the accepted methods to achieve real production.