Microscope Your Material
Under a microscope, the surface of the material is all fuzzy.
Imagine painting a brick wall, the paint will easily soak in because the surface is rough.
Imagine painting a vinyl film. The surface is less fuzzy.
Dyne tells you how fuzzy the surface is. You cant put the banner material under a microscope everytime, so you use a dyne pen. It shows the viscosity level (surface tension) of the surface and how the ink will absorb.
Anything under #38 and you'll have problems and the vinyl material supplier has given the reason for your problem. If you have material that achieves #44, it also helps your dry time and you can print faster.
You should be able to buy from any local UV or Flexo printing supply company in your area.
You simply run the dyne pen (just like a texta) and it will show how the ink laydowns and surface tension of the vinyl material.
Particularly helpful for those use cheap water based dye inks.
See USA
http://www.novasys.com.au/uvps1.htm
http://www.australiabanners.com.au