Do fabrics need to be 100% polyester for dye sub printing?

While you do need at least 60% polyester fabric to successfully dye sub print, it is better to use 100% polyester because you will attain a superior print if 100% of the fabric accepts the dye when it enters gas form and is inducted into the open polymer pores.
What you may not know is how this process works and why polyester fabric is the best product for dye sublimation paper printing, whereas cotton, wool, and even nylon will not work for this type of printing.

Starting with the dye, it is necessary to know that the dye is not the same type of ink as inkjet inks which use the CMYK (cyan-magenta-yellow-black) ink set, but instead, use a CMYO dye set (cyan-magenta-yellow-overprint clear) where the clear, when it is printed on the dye sublimation transfer paper, turns to black and transfers that way.

Once the sublimation paper is printed, it is joined, print side to whichever type of material you are using, then put through a set of heated rollers. The heat must be in excess of 370º F (190ºC) to cause the dye to be converted into a gaseous form, and also to cause the polymer’s cells to open as they expand to accept the now gaseous dye into the cells.
Once this process has taken place, the fabric cools, the cells close, and the color is permanently locked into the fabric in continuous tones of beautiful color, similar to a photograph’s tones.
Without the cellular construction of the polyester fabric and it’s polymeric qualities, it would not be possible to print using dye sublimation. So, the more polymers, the better. So the answer is, of course, yes and no. We recommend using 100% polyester, but it’s not an absolute requirement.
More info:
Website：www.skyimagepaper.com
Company Name: Fei Yue Paper Industrial Co.,LTD
E-mail: sales@feiyuepaper.com 
Tel: 86-025-83228884
Whatsapp: +86 18252072197

Address: Central Road 323, Nanjing, Jiangsu, China