Pad printing is a marvelous type of printing that has allowed for companies the world over to leave their marks on objects no matter the surface. Curved, bumpy or flat, nothing can escape the capabilities of this type of printing. However, such a versatile progress is actually much simpler than one might assume.
The entire procedure can be broken down into three different stages based on the part of the machine being utilized.
Step One: Cliché
The cliché is the plate that has the image or logo sketched onto it. It is typically a hard steel to guarantee that throughout the printing process, the image itself does not become distorted due to general wear and tear. Unlike many logos, this one is concave, carved inward so as to create a well where the ink is placed during the second step.
Step Two: Ink
This is the broadest step since there are as many different inks as there are items to print on. From every color of the visible spectrum to varying grades that change based on the material being printed on, these inks are incredibly numerous. There are even edible inks for candies and medical grade inks for sterile environments. What is used is determined by what is being printed on. Once chosen, the ink the fills the cliché.
Step Three: Pad
To transfer the ink to the item being printed on, a special pad is used. Once gelatin wrapped in cheese cloth, it is now typically silicone with a hardness that varies based on the needs of the project. Silicone has proven to be a wonderful material because the ink from the cliché temporarily sticks to it, allowing the pad to pick the ink up and transfer it over to the object. Pressure is then applied onto the object and the ink transfers to the item without suffering any sort of distortion. The hardness mentioned earlier is what allows logos to be pressed across the rough surface of a basketball or the smooth ridges of a baseball.
While the steps are simple, there are a variety of environmental factors that factories have to keep under control while pad printing. The biggest concern is humidity. Because the ink is left out in the open for even a few seconds of time, too much or too little moisture in the air can lead to a variety of problems. If there’s not enough moisture, the ink will dry too quickly, sticking to the pad and not transferring. If there’s too much, the ink won’t dry enough to become tacky enough to stick to the silicone pad. On top of this, temperature can even directly affect how the ink acts. In short, liquid is very temperamental, however the benefits of pad printing have made such specialization well worth the investment.