Research discovers the effects of the environment and hair care products on hair fiber
Bharat Bhushan, Eminent Scholar and the Howard Winbigler Professor
of mechanical engineering at Ohio State, has done some significant
research into hair conditioners and high-tech products with specially
developed equipment. Bharat Bhushan and his team specialize in
Nanotribology - an advanced and newly developed field of research
which involves the measurement of very small matter, such as the
friction between moving parts in microelectronics.
Dr Bhushan, was invited to give a lecture to a group of Proctor & Gamble
scientists, and together they concluded that friction is potentially
a major issue with hair. Though the subject matter is quite different
and perhaps strange for a mechanical engineer to study, fundamentally
the research is very similar to Dr Bhushan’s more usual
focus of tiny motors. With the encouragement of P&G, Dr Bhushan
and his colleagues were drawn to the project and the study of
friction in hair fibers.
When the hair is rubbed or combed, some electrostatic charge
is produced in the hair, which is actually a direct result of
the friction. Many hair grooming activities, such as brushing,
dying, and styling cause friction on the hair fibers, and this
may actually lead to wear and tear and damage to the hair fiber.
The team of Ohio State engineers examined hair under an atomic
force microscope (AFM), which is a tool that lets them scratch
the surface of hair fibers and probe inside the hair shaft with
a very tiny needle.
The study revealed that hair conditioners do not always evenly
cover the entire hair shaft, which may prove to be a major factor
for product’s efficacy.
In response to this discovery, P&G have developed a new hair
conditioning formula with additives to make the conditioner coat
the hair evenly. So far, experiments done by the Ohio team with
this conditioner showed the new formula had a superior hair coating
effect. It was a great result and demonstration of the product’s
However, the team did not stop there and continued with their
experiments. They next studied healthy and damaged hairs under
an electron microscope and an AFM.
It is widely known that damaged hair cuticles begin to peel away
from the hair shaft, which creates unmanageable and lack-luster
hair. So the next step for the researchers was to determine the
factor that causes this damage. The day to day wear on the hair
was simulated by rubbing hairs together and against polyurethane
film to simulate skin.
The scientists noted that when damaged hair is exposed to humidity,
they plump up, and the cuticles stick out even further, leading
to even more friction and frizz – a fact confirmed by the
AFM as the researchers dragged a tiny needle across the surface
of the damaged hairs. This is where the importance of hair conditioner
design comes into play.
By poking the hair fibers with the AFM needle, and measuring
the force required to pull it away, the scientists determined
that normal conditioner tends to stick to the cuticle edges and
that can make the hair stickier on the Nanometer scale. Newer
hair conditioning formulas should coat the hair fiber more evenly
and reduce the amount of conditioner that sticks to the edges
of the hair cuticle. This in turn should give a smoother appearance
to the hair fiber and help reduce friction.
The scientists also probed inside hairs to measure the hardness
of different layers of the shaft. Hair has a very complex structure,
Bhushan said, and these first ultra-precise measurements of interior
structure could one day lead to new products that treat hair from
the inside. The researchers have expressed great confidence in
the future of this research and its extension into other areas
like lipstick, nail polish and other beauty products.