Learned something crazy about purple hair dye today

I was at a supply shop near St. Paul this morning and the owner told me that purple pigment molecules are actually the biggest of any color in the visible spectrum. That's apparently why purple fades so fast on clients, those big molecules can't penetrate the hair shaft as deep. Made me rethink how I layer my purple formulas for sure. Anyone else run into issues keeping purple vibrant past 2 weeks?

3 comments

3 Comments

carter.laura17d ago

Oh wow, that molecule thing is wild! I totally feel you on the fading struggle though. I've had purple hair a few times and it's like it just decides to peace out after a week and a half no matter what I do.

reese_nelson17d ago

Huh, I always thought purple faded fast just because it's a dark color that's hard to keep in? That molecule size thing actually makes a ton of sense now, I've definitely noticed my purple clients coming back quicker for touch-ups compared to my blues or reds. Guess I've been blaming the wrong thing this whole time, really makes me want to look into different purple brands to see which ones stick better.

the_jordan17d ago

Actually there's been some research coming out of a few cosmetic chemistry labs that tested different purple pigments and how they bond to hair. Something about the size and shape of the molecules used in cheaper dyes makes them slip out way faster. I saw this breakdown from a salon science blog where they compared three popular purple brands under a microscope and one of them had these massive clumps that barely stuck to the cuticle. The brand with the smallest, most even particles held color almost twice as long in the test. Might be worth checking ingredient lists for something like Basic Violet 2 versus Basic Violet 1 since the molecular structure is slightly different.