Hair Types and Required Specific Ingredients for Conditioning ...

3. Test Methods for Determination of
Conditioning Property Improvement
In Figure 3 an overview of the test methods used to assess the conditioning properties of conditioning agents is given.
These methodologies can be differentiated into technical measurements and sensory assessments.
Technical measurements on hair swatches
• Combing force measurements
• Body/volume measurements
• Curl retention tests
• Antistatic test:
Fly away measurements
• Measurements of the wash fastness of
semipermanent/permanent dyes
Sensory methods
• Hair swatch tests
• Technical tests done by hairdresser (Salon tests)
• Consumer tests
Figure 3: Test methods
Technical measurements
One of the most common measurements is the determination of the combing forces. This method allows measuring
forces, which occur while combing in a high sensitive manner.
To do the body/volume measurements, the hair swatches are pulled through a ring. The force measured in this design
is mainly influenced by the compression of the hair tress into this ring [2].
The curl retention test (Figure 4) is normally used for styling products. We did this test for the differentiation of
conditioners. The change of humidity directly effects the water content of hair and plastifies the hair cortex. The
conditioners may make the surface more hydrophobic, reducing the absorption of atmospheric water. This
hydrophobizing effect keeps the hairstyle more stable and is also important for curly hair in order to avoid frizzyness.
To measure the antistatic properties of conditioners, we use the shadow contour method (Figure 5). Under defined
climatic conditions the hair swatch is fixed in front of a centric measuring scale. By using a light source, the shadow
image is created and the spreading before and after charging by defined combing is measured.
The measurement of the color protection or wash fastness can be done by using a spectrophotometer. Hair swatches
are dyed with a permanent or a semipermanent dye and after drying the CIE-L*a*b-colour values are measured. This is
done again after a defined number of treatments (shampooing and/or treatment with a rinse). The lower the difference
of the color values is, the better is the wash fastness property of the tested product.
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