I use color catchers in all my color loads of laundry because I never know 3 boys and 1 girl. I never pre wash fabric so I always wash a finished quilt by its self with a color catcher. I have never had an issue and I just did a quilt with different blue batiks mixed with sand color batiks, nothing ran (the color catcher was blue). Investing in all the extra I haven't seen a need to do. I have a pale yellow and red quilt almost done so we'll see but again I've done yellow before with no issue.

synthropol is used mainly in preparing fabrics for dying. It is like a detergent that will remove all the sizing, oils, chemicals, and opens the fibers of the fabric so that the Urea/salt/dye mix will adhere to them better.

That doesn't make sense though ...
... as above, it's an after-dye product ... and takes the excess colour away, so it does not "re-attach" to fabric.

So?

QuiltE, that's it's original purpose...the 'scouring' of fabrics to prepare them for dyeing. You can turn any commercial fabric into PFD (prepared for dyeing) fabric by washing it with Synthrapol. For instance, if you wanted to overdye a white TOT print, you'd wash it with Synthrapol before dyeing so the fibers would be more receptive to the dye.

The chemicals and such are not bonded to the fibers (they just sit on the surface), so Synthrapol washes them away...just as it washes away loose/excess dyes that are not bonded to the fibers when used as we have been discussing earlier. Make sense?

Yes and No!!

So if it attaches new dye ... why doesn't it attach the old stuff, rather than wash it away?

Yes, you can colour me confuzzled to the max .... and just when I thought I "had it"! :D

It doesn't attach new dye, it makes the fibers clean and receptive to dye. The dye/urea/salt mix attaches itself. Synthrapol is like sort of like Brillo. It removes loose things...chemicals, dirt, loose dyes, and over time, even some not-so-loose dyes I suspect (iow, it will fade fabrics).

Gotchya ....... I think! :D

Sooooooooo ..... if one were to think of tea dying some fabric, synthrapol first to brillo it up ..... and then the tea? And then retayne to keep the tea on it? Or is that a subject for another thread? If so, tell me .... I'll start one!

The analogy that came to mind:

Using Sythrapol before dying fabric - similar to scrubbing/cleansing one's face before applying makeup

????

Good one .. I guess Ghostie and I, Brillo our faces! :)

While we are discussing these products, I am looking for some tea dye product that can be placed in the washer. I do not want to use regular tea or coffee. I thought RIT made a product called Tea Dye but can't seem to find it on the internet or in a store. Can any one offer a suggestion? I have a rescued vintage quilt top that has some red (very very faint) that I would like to disguise with a tea dye.