The Physics of Sublimation
Published on September 16th, 2019
The sublimation industry has taken off rapidly and while that’s awesome for those of us who have been navigating the market for a while, it can be very confusing for people who are just starting out. Lately, we’ve noticed a flood of questions on our Facebook forum concerning what some of us may consider the basic physics of sublimation and hopefully a basic walk through the process can help those struggling to understand.
- What makes sublimation ink different from other inks?
- Why should I use sublimation paper when I can just use copy paper?
- Does a certain sublimation paper transfer better to dark fabrics?
- Why do some colors appear more vibrant on one substrate than they do another?
- Why do cotton blends not accept ink as well?
According to Dictionary.com Sublimation is the process in which a solid can transform directly to a gas without going through a liquid phase first, a good example of this being how dry ice can create a fog but never actually melts. For us, this knowledge is relevant because the ink pigments in sublimation dye are turned into a gas; which then penetrate the surface of the material being printed. Sublimation can take place due to heat, pressure, or both.
- Sublimation Ink is comprised of two basic elements: a colorant and a liquid. The colorant is solid pigment and the liquid keeps those pigments suspended. Unlike an inkjet cartridge that uses color pigment dissolved in liquid, sublimation inks unique makeup of tiny suspended particles allows for more vibrant colors, although initially colors may seem dull because the full spectrum isn’t obtained until after pressing. Color profiles are critical in reaching the inks full capability so be sure to use the settings administered by tech support.
- A dye-sublimation printer then places those solid ink pigments onto a transfer medium, sublimation paper. Paper choice is essential because different papers handle the ink in differing ways. Sublimation paper has a special coating that helps it control the sublimation ink without absorbing it. With the ink pigments on the carrier paper they can be effectively released into the substrate by way of heat press. Unlike copy paper, which can absorb ink and cause images to blur, sublimation transfer paper allows for the maximum ink release and a much crisper image.
- With that said, the sublimation process is going to be the same no matter which sublimation paper you use, so technically there is NO ability to sublimate on darker colors. Unless you lay a sublimateable white layer down first (such as EasySubli™, SubliSparkle™, or SubliFlex), an image will not show because an image can only be as light as the substrate it’s printed on. Attempting to print on dark colors will only yield dark results. Sublimation paper is only a means for carrying ink and has no effect on how the ink will function. Imagine laying a piece of colored glass on a white tablecloth and then a black one. You will still see the darkness of the black tablecloth behind the glass no matter what color the glass is.
- After printing to your paper, the next key step involves a heat press. While doing this, make sure that your paper is adhered to the substrate securely to prevent the paper from shifting and ghosting your image. The press brings the printed transfer into contact with the substrate that is to receive the image and the heat causes a physical change within the ink. Under the heat and pressure of the heat press, the solid dye on the printed paper is converted to a gas which penetrates the openings of the heated poly-coating and bonds with it. Sublimation dye is an oil loving molecule and can easily be bonded with polyester because of the way poly opens to accept ink. Natural materials such as cotton and wood won’t hold the ink and will instead burn as you attempt to sublimate them.
Example of ink being overlain atop a gradient of white to black
- As soon as the heat and pressure are released, the dyes start to solidify back into pigments and the openings close. This bonding process creates a vibrant, permanent image that won’t smudge. With that said, poly substrates accept ink differently for various reasons. The rigidity of the material and poly coating are key components in this variance in addition to the time, temperature, and pressure used. Always be sure to test color settings, instructions, and imprinting as this is the most important step of all.
Luckily, Condé is tirelessly testing products and pioneering improvements to the sublimation process. Condé is an amazing company with a friendly sales staff who genuinely want success for our sublimation family. That’s why we choose quality products and give all the knowledge we obtain directly to our clients. In addition to company transparency, each of our sublimation blanks have instructions and templates to make printing as easy as possible. Please utilize our massive video library on CondeTV, regularly tune in to our Facebook/YouTube lives, and visit us at tradeshows to learn about the latest products. Whether you are just looking for inspiration or needing help with print services, we are here to streamline your processes and help you on your journey towards success!