People are telling me that this could be interesting, so I wanted to share with you.
Heat transfer printing – Identifying and resolving problems
Holger Beck, SEF – The digital transfer printing market has been growing for years. While this has to a certain extent displaced classic screen printing, it has also opened up new opportunities and markets. The barriers to entry are low: all one needs to get started is a small investment into a plotter and a transfer printing press. The potential problems have remained the same, but new problems are caused by the new process fabrics. A multi-part series of articles is designed to help users to identify problems and to develop possible solutions. There are no silver bullets for every issue, but users can develop a recommended set of actions by having an understanding of the background. As a result, the work can proceed faster and more cost-effectively, while also avoiding customer complaints.
I would like to devote this part to a subject which is often called “Resublimation”. In my view this description is not correct. The term Sublimation is used to describe the process whereby a solid substance turns into a gas or vapour without passing through the intermediate stage of liquefaction. The term “Resublimation” gives the impression that something has been sublimated again. However with the pigments used in fabric printing, Sublimation only occurs at temperatures over 190°C, but not at the usual transfer temperatures and certainly never at room temperature. When transfer films become discolored on polyester fabrics it should be called dye migration. I would like to try to explain how dye migration occurs and what you can do to counter it and to what extent.
Problems with dye migration can be divided into 4 categories, the simplest of these is: no polyester, no dye migration.