What is a Heat Transfer?

Promo Expert

Published: May 11th, 2020

Heat transfer (also called heat press) is one of the many processes available to make your promotional items look fantastic. It uses high temperatures to transfer your custom design onto fabric, but that's just the tip of the iceberg. Take a look at this lesson to learn more!

If you were a kid who had one of those iron-on patches that had to be applied to clothing using a laundry iron, then you have some idea of what heat transfer is all about. And now, as an adult, you get to appreciate all of the scientific know-how (and the industrial machinery) used to make heat transfer possible.

Let's Turn Up the Heat!

Heat transfer starts with a design printed in beautiful full color onto a piece of paper. This isn't any ordinary piece of paper, though. You can't just print your design on regular notebook paper and hope an iron will press it onto your backpack. That's a good way to start a fire!

Instead, heat press uses a special Teflon-coated paper that's made to withstand extreme temperatures, as well as other kinds of wear and tear. The back of the paper is coated with an extra-strong adhesive to make sure your custom design won't peel off of your items for a long time.

Heat Press is Forever

Once the design has been printed, trimmed, and set into position, it's time to make it permanent. Remember how heat transfer was a lot like using those old iron-on decals? Well, here's the point where you'll really see a difference.

In order to accommodate large-scale custom orders, manufacturers have to use large-scale industrial equipment. Makes sense, right? These are significantly larger than a regular iron. In fact, the heat press machines used by manufacturers are probably a lot bigger than what you have space for in your laundry room or basement.

Wow! That's Hot!

When that giant iron comes down to press the design into the fabric, it operates at a pressure of 30 to 40 psi (pounds per square inch). For comparison, the pressure inside of USA-made pressure cookers is 15 psi, while most hot water heaters operate at pressures between 12 and 25 psi. These giant irons are extremely powerful!

Heat transfer machinery works at temperatures above 300 degrees Fahrenheit. At such high temperatures, the adhesive on the back of the special transfer paper melts right into the fabric. It doesn't take long before your design becomes a thing of beauty that people will marvel over for years.

When it comes to transferring your logo onto promotional products, the hotter the better! Heat transfer is a much more complex process than using an iron to put patches on your jean jacket. The machines operate at 300 degrees Fahrenheit and 30 to 40 psi of pressure. Overall, there isn't a printing technique quite as hot as heat transfer!