Cosmetics
At the forefront of nanotechnology in cosmetics
we see companies like lOreal, producing anti-wrinkle cream containing
nanocapsules, which help active ingredients get to the skins deeper layers. By
reducing the active ingredients to a very small size and coating them with a
biodegradable polymer, the company found the nanocapsules were small enough to
pierce through the first layers of the skin and release the active ingredients
below, in the lower layers of the skin.
Anti dry skin crmes use oxide powder with
nanosized silica powder. Zinc oxide nanoparticles scatter the light, thereby
protecting the skin. Besides that, ultra-fine titanium dioxide with the
inclusion of a small amount (<1%) of manganese can catalyse free radicals
that have been generated by other sunscreen components into harmless chemical
species.
Sports
Even small improvements in material properties
can be crucial in sports. Not surprisingly sport aricles are a popular testing
bed for nanotechnology. Some examples:
- A hockey stick based using
carbon nano tubes to combine carbon fiber and epoxy on the molecular level
in a new way and realizing
- Tennis balls containing
hundreds of nanodispersed platelets per micron of coating thickness
forming a tortuous path for gas molecules thereby increasing the barrier
properties.
- A ski wax containing nanoparticles organizing themselves on the surface automatically.
Therefore they have a high amount of fluorine at
the surface and uniform distribution.
Self Cleaning and User Adaptable Surfaces
The leaves of certain plants and the wings of
insects always stay clean because dirt and water cannot adhere to their
structured surface. The lightest rainfall can therefore clean the surface.
Learning from that observation. several nanostructured top layers have been
proposed and are applied to create self cleaning surfaces.
Electro-chromic materials, another example, are
able to change between a transparent and an absorbing state through the
application of a low voltage (only a few volts). A foil consisting of thin
oxide layers is laminated between two flexible polymer sheets. The foils are
first coated with a transparent electrically conducting layer and then by
active electro-chromic layers. The user can easily control the transparency using
an electronic control unit. The visor changes between dark and light conditions
in a few seconds.
Nanocoatings can even be used as ski-wax. The
ultra thin coating changes according to the temperature and adapts to the
surface and snow-crystals. The surface structure remains completely free of wax
enabling optimum gliding.
Other examples of nano surface coatings are:
- Titanium dioxide (TiO2)
crystals, only 40 nanometers in size, formed to a layer and acting as a powerful
oxidizing agent, destroying airborne germs and pollutants.
- An
aqueous suspension, applied via roll (or dip, or spray) coating process onto a
substrate forms a tortuous path for molecules such as oxygen and aromatics.
This increases the barrier properties of the substrate and makes the materials
more air thigh. Is being now introduced in tennisballs.