Solufix is a self adhesive water soluble fleece commonly used in machine embroidery as underlay. After embroidering you rinse it out with water. Cold water will do, warm is quicker. 
Solufix is printable, just cut to size and print...
This kind of underlay is handy when embroidering stretch fabrics. Take the size of the embroidery hoop and a little extra. If you include the solufix when you secure the fabric in the hoop it will stay put making the embroidery proces easier and with a better result.

Difficult to choose your interlining? Check out our Vilene choice help (dutch)

Blog about solufix and it use (dutch)