I recently got this question from a good customer about Reds bleeding to pink in tie dye. This is a common problem and reds are the most difficult color to wash out and to keep from staining the white areas.
Here is how I answered her question:
I use Red #9 (5 tsp to 1 cup chemical water to get a nice deep red), but I'm having a lot of trouble with the whites of the tie dye turning bright pink when I wash them out. Would a different color of red dye be better? Any other ideas? I have tried using less dye pwd. but I can't get a deep red when I do that....
HI, I think the trouble is more in your wash out. Here is how I wash out loose dye with very little color bleeding..
1. Leave fabric tied up
2. Let it sit a long time before washing out loose dye.. the longer I let my fabric sit, the less bleeding I have..
3. take TIED UP fabric to sink and rinse each piece one at a time under cold running water.. a lot of loose dye will come out ..this is normal.
Don't untie the fabric until most of the water is running clear..
4. Untie and wash in warm soapy water.
If this does not work well for you, there are other things you could try adding some vinegar to your initial rinse water. Vinegar is an acid that will help neutralize the alkaline that makes the dyes react. We normally don't do this as our wash out procedures work well for us.. but we do know that some people do this.
As for the dye itself, most reds use fuchsia as a base, including Red #9, Scarlet and Deep Rose Red. You could try other reds that are not fuchsia based such as Bright Red #12, Mixing Red, Cherry Red or Fire Red, and you might have better luck with those.