I’d always heard that science had not progressed to the point where certain shades (i.e. blue or violet) could be dyed permenently (all blue dyes i’m aware of will come out a little bit every time you shower, and bleed onto stuff they touch)…apparently some company named goldwell has come out with this weird substance that supposedly does the job…anyone familiar with it? Does it work?
perhaps a board full of academics and intellectual-types ain’t the best place to look for advice on blue hair dye 
?
Is that the one Marge Simpson uses?
Why not?
But I don’t know, I don’t look good in black hair.
http://www.elumen-haircolor.com/
Goldwell claims that it’s a new breakthrough, so I can’t tell you much. The process apparently includes a set of mixable colors (which will stain, and must be removed with the Elumen “Clean”) and a “lock” which is applied afterward. I assume that it’s the “lock” that is really responsible for any great durability.
Traditionally, long-lasting dye jobs require bleaching beforehand, and use of penetrating hair dyes (“para” dyes, made from coal tar), which have never been available in blue. Goldwell claims that their dyes require no oxidation, but penetrates the hair shaft through a “physical process.” They also claim that their “acidic, direct-color dyes” cause less damage to hair. They also claim the interior of the hair shaft is positively charged, so I don’t don’t what to make of it all.
BTW, I don’t see any blue coloring in their line-up, although there is a pretty good purple.