Coloring one's hair is a regular personal care routine for many people. It is often used as an avenue to self-expression or as a way to stand out from the crowd. However, the actual process of coloring is not usually a favorite chore.
Most commercial hair dyes have the disadvantage of being potentially irritating, damaging to property or surfaces and smelling to a horrific degree. Even newer formulations contain chemicals that could be toxic to the environment at their disposal.
Therefore, the next generation of hair dyes may have to become much more neutral in all these areas, to improve one of the universal forms of self-decoration.
But, hair-colorant developers had probably never considered graphene as a viable alternative ingredient...until now. It seems that the material is indeed versatile enough to match even this potential use-case.
Why Graphene as a Hair Dye?
Graphene, which is a two-dimensional arrangement of carbon atoms, is becoming a more popular component in many academic and industrial pursuits. It has many fortuitous properties, most notably high electrical conductivity, which makes it very amenable to areas such as electronics.
However, it now appears that graphene is also potentially useful in other, slightly unexpected, areas such as textile processing. In other words, it can be used as a dye.
A team of researchers, collaborating across departments of Northwestern University and the Shenzhen Key Laboratory for Graphene-Based Materials, set out to test the feasibility of a graphene derivative as a colorant for human hair.
The derivative, graphene oxide, was found to be able to wrap around the external layer of a hair strand, known as the cuticle, firmly enough for the strand to be considered dyed. Graphene oxide-dyed hair was also appreciably resistant to washing and also improved anti-static properties.
Therefore, the graphene-based dye could help in avoiding the appearance of frizz or excessive drying in hair treated with it. Further, graphene oxide is also touted as an anti-bacterial and highly flexible product.
So, the Shenzhen/Northwestern team's new putative hair dye would be durable and long-lasting. The product may also be able to protect the hair it colors, through these desirable properties
In addition, the team suggested that the new color may be less harsh on the hair, in the long term, compared to conventional permanent dyes.
Comparing Hair Dyes: Regular vs. Graphene
Commercially-available products function by partially disrupting hair structure at the molecular level, in order to insert the desired color into the locks and ensure that it is visible to the human eye. To this end, the dyes are complex formulations made of numerous small molecules, some of which may be toxic.
Graphene oxide, on the other hand, forms a uniform coating around individual hair strands that adhere strongly enough to resist removal through washing. Furthermore, this new form of hair dye can be applied via a spray that is then left to dry on the hair.
Regular hair dye may need to be applied as a solution in a lengthy, and often messy, process. Subjects then have to wait with the wet colorant on their heads, for a pre-defined length of time, while the dye sets. This process is typically inconvenient for the colorist and the individual in need of the color.
On the other hand, the result from traditional dyes can range from natural to metallic shades, which the new graphene-oxide dyes currently lack.
Graphene does not normally reflect light. Therefore, its natural color is black. Accordingly, hair dyed using graphene oxide is also black.
However, the team behind this innovation claim that variations in the concentration and formulation of the dye can modulate the shade, and give a graduated effect.
Graphene-based dye typically results only in black colored hair, but the scientists claim that with the addition of different molecules and formulations can results in various shades. Image to the right is also showing the structure of graphene. (Source: Chong Luo et al., 2018)
It remains that the only colors currently available in the team's prototype dye are black or brown. But, other colors may be possible through changes in the molecular formation of the graphene, or the addition of different molecules.
Presuming that graphene-based hair dye can be brought to the market and compete in terms of shade and color, regular colorants may gain a sizable competitor. Although, the team of researchers will have to demonstrate further development before that goal can achieved.
The current prototype, thus far, has been depicted as capable of dyeing hair samples. But, it is not clear as yet how the product would perform on a full head of living hair, complete with scalp and follicles.
Though, it is apparent that graphene oxide particles cannot be absorbed into the skin, as with conventional hair dyes - the molecular size of the former is too large. Hence, it may turn out that this form of hair dye will be safer to use in the future.
In addition, the team argues that the waste products resulting from graphene dye use or production can be re-purposed for application in industries such as electronic components manufacture.
Furthermore, they pointed out that graphene dyes also make surfaces treated with them more conductive, hair included. Therefore, the colorant could also find use in the implementation of wearable technology of the future. These devices may be mounted onto or even integrated into the skin or clothing for health-tracking and other functions too.
All in all, this innovative take on hair care could offer more evidence that the future is graphene-powered.
Top Image: Blond hair before and after treatment with a graphene dye. (Source: Northwestern University)
Luo C, Zhou L, Chiou K, Huang J. Multifunctional Graphene Hair Dye. Chem. 2018. Epub ahead of print. Available at: https://www.sciencedirect.com/science/article/pii/S2451929418300822
Morris A. Graphene finds new application as non-toxic, anti-static hair dye. EurekAlert. 2018. Available at: https://www.eurekalert.org/pub_releases/2018-03/nu-gfn031218.php