Hi Frances
I've just got the reply back from my friend Ruth and she says
As for your question about Durabrite and polyester, I don't know about the Ricky Tims stuff but I've printed on to polyester satin and polyester sheer and it washed without any problems but you do need to make sure it's thoroughly dry before you wet it (that sounds a bit odd but you know what I mean).
The following is an excerpt from her book about testing your printer/inks, which is essentially what Margo was suggesting, print one piece to try it out and see if it works.
If you want to test the ink in a printer you already have, just
print a piece of untreated fabric and let it dry thoroughly –
see the chapter on ‘Direct Printing’ for how to do this. Then
wash it - a quick, gentle hand wash will do . If some or a lot
of the ink comes off then your ink is dye-based. If it looks
pretty much the same then your ink is pigment-based.
Hope this helps
Rosemary
PS small advert - her book will be coming out this autumn, but I don't as yet know the title. Available at
http://www.stonecreeksilk.co.uk