Body
Using
our proprietary ring method, we measure tress compression
energies and relate them to a formulation's ability to increase
body, volume, or texture.
Bounce
& Resilience
Torsion
studies, which can be made at ambient humidities, add information
about viscous dissipation and storage modulus of the fiber.
A high storage modulus, for example, will translate to desired
attributes of flowing, swingy, or movable hairstyles.
Coating
- Product Deposition
Microfluorometry
is used to characterize product deposition on the surface
of the fiber. The TRI/SCAN™ Surface Force Analyzer measures
uniformity of a compound on the fiber surface. These techniques
can measure evenness of distribution and the thickness of
the coating all along the hair fiber.
In addition,
A PC-based imaging system including video playback that is
very useful for studying the interactions of fluids with single
or crossed hair fibers. The instrument has been used to observe
the interactions of hair fibers with hairspray and shine sprays.
Color
Retention/Fading
Color
change or dye fading from effects such as shampooing, sunlight
or chemicals is quantified using a HunterLab UltraScan XE™
spectrophotometer.
Curl
Retention
This
can be used to test the efficacy of perming formulations and
styling fixatives. Also, how well fixatives function to give
hair shape, style and control.
Diffusion
of Product into the Hair Fiber
Diffusion
of products can be measured using microfluorometry or TOF-SIMS
(Time of flight secondary ion mass spectrometry). Diffusion
of any substance into the hair fiber can be seen and quantified
over time.
Flyaway
Reduction
A Faraday
Cage measures static charge and is used to test the anti-static
properties of products.
Heating
Profiles
By placing
a thermocouple in a heat tress, the temperature profile during
heat treatments can be measured. We can then study the effect
of extreme heat on properties like resilience, strength and
hair health.
Holding
Ability
Measuring
the force required to separate bonded hair fibers using a
very sensative microbalance will give information about the
hold strength of hair fixatives.
Manageability
Coming
force measurements demonstrate a product's efficacy in increasing
combing ease and decreasing tangles.
Moisturizing
Ability
Our Dynamic
Vapor Sorption™ analyzer provides sorption/desorption
isotherms which determine the moisture retention ability of
various moisturizing agents.
Product
Build-up
Microfluorometry
is used to characterize build-up on the surface of the fiber
which can weigh hair down. The TRI/SCAN™ Surface Force
Analyzer measures uniformity of a compound on the fiber surface
and build-up. These techniques can measure the location and
amount of product deposited all along the hair fiber and evaluate
products for removal of build-up.
Shine
A light
scattering goniophotometer can measure luster values of both
single hair fibers and tresses. This translates to consumer
perception of shine and gloss.
Smoothness
& Sleekness
Interfiber
friction studies illustrate the improvement to the hair surface
from product applications. The lower the interfiber friction,
the smoother hair will look and feel - less frizzy. In addition,
the TRI/SCAN™ Surface Force Analyzer calculates surface
energy of fibers which is a very sensitive measure of hair
health.
Softness
Using
our proprietary ring method, we measure tress compression
energies and frictional forces and relate them to a formulation's
ability to increase softness.
Strength
The TRI/Hair
Fatigue Tester™ quantifies improvement in strength of
fibers by cycling the application of a preset weight to 60
hair samples concurrently and measuring cycles to failure
for each specimen. Also, we generate stress-strain curves
for dry or wet hair using a Diastron™ and calculate parameters
that characterize the mechanical properties of hair, such
as work to extend and work to break.
Surface
Modification
Very subtle
changes in the surface of a hair fiber can be examined using
Scanning Electron Mircoscopy. For example, TRI scientists
have shown how wet combing causes the cuticle cells of hair
fibers to chip off, exposing the weaker cortex beneath. This
leads to lower strength, shine, and resilience. Other examples
of surface modification include fusing of cuticle cells from
UV damage, product deposition, and chemical damage.
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