Close
Expert Advice

Chem 101: Direct dyes

Web Editor | July 10, 2011 | 6:16 PM

Chem 101: Direct dyesAs the key pigments in temporary and semipermanent color, direct dyes have been around for a long time, but today’s sophisticated color formulators are using the technology to achieve effects far more dramatic than your mom’s “rinse.”

Direct dyes are pre-synthesized, so the color is already fully formed, requiring no oxidation, no developer.

According to Martin Uellner, Goldwell’s category manager, R & D Color & Perm, due to their often-larger molecular size, it’s difficult for direct dyes to penetrate the hairshaft.

“Most of them act more on the outside of the hair, leading to low durability,” he notes. “Their benefit is they are very bright and intense.”

Uellner says the dye’s tendency to fade can be suppressed by a special penetration agent, like the one used in his company’s Elumen line. Direct dyes in the classic semipermanent color are normally cationic, but Goldwell uses anionic (acidic) direct dyes in Elumen which, says Uellner, don’t cluster so they can penetrate easily. An electrostatic attraction also anchors them to the hair, he says.

In the fabric-dying world, negatively charged direct dyes are somewhat repelled by negatively charged fabric, until salt or an ionic agent is used to create a positive charge, allowing an ionic bond to form between the two. The difference with hair color is that the pH of the base formulation is creating positive-charged hair, which attracts the negative-charged dyes.

Direct dyes, whether used as the central pigment as in Elumen and Keune’s Color Contrast or as part of a combination oxidative and direct technology as in Wella’s Magma or Schwarzkopf’s Igora Vibrance, are for creating intense results. Pick a conventional permanent or demi formula when you want more natural shades.

Send your chemistry questions to [email protected]

Facebook Comments

More from Expert Advice

Your Little Guide for BIG Spring Promotions

April 5, 2017

Do you dread thinking of new ways to reinvent promotions and special occasions? How many times a year can you discount the same service, the same way, without your clients becoming accustomed to a “holiday promotion”? Fortunately, the abundance of springtime holidays and special occasions allows for a variety of fresh ways to delight your customers.

Expert Advice
Expert Advice

Why Professionals SHOULD Sell Retail Products

Maggie Mulhern | February 28, 2017

It has been a problem in our industry for years - retailing. Many salon pros have trouble seeing beyond the artistry and find it difficult to sell products to their clients. In this brief video Cody Fullerton of Living Proof confronts the situation and shares why salon pros should encourage their clients to buy products to maintain their hair between salon visits.

Load More