PERSONAL CARE

Radia ® emulsifiers belong to the anionic and non-ionic surfactant classes. Anionic emulsifiers
presented below are outstanding candidates for natural formulations. They are primary o/w
emulsifiers recommended for all types of skin care preparations. Selection of the suitable
emulsifier can be oriented by the HLB system which represents the hydrophilic and lipophilic
tendencies of the surfactant. HLB values will depend on the ratio of these properties. These
values vary from 0 to 20. Radia emulsifiers with low HLB, such as sorbitan esters, will behave
as w/o emulsifiers. On the opposite, ethoxylated sorbitan esters, polysorbates, will behave
as o/w emulsifiers. In general, emulsifier systems show better results than single emulsifiers.
Resulting HLB of the blend can be calculated from the sum of the emulsifier percentages
involved. As an example, sorbitan esters will be added to polysorbate based o/w emulsions to
stabilize creams and lotions.
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PEG esters result from the esterification of polyethylene glycols with fatty acids. The processing
conditions and the raw materials selected allow to obtain emulsifiers with a wide range of
HLB values. Besides their emulsifying properties, PEG-10 dioleate, as an example, will be used
in bath oils to help forming a continuous film on the water; PEG-10 stearate in cream shampoos
to lend opacity and body, … Polyglycerol esters are recommended as w/o emulsifiers.
Method
color
Value
POUR POINT,
°C
CLOUD POINT,
°C
MELTING POINT,
°C
VISCOSITY AT 40°C,
mm 2 /s
Lovibond 1" 5Y-1R 56-60
Lovibond 1" 6Y-2R 59
Lovibond 1" 30Y-6R 45-55
Gardner < 5 21 23 1200
Gardner < 6 50-60
Gardner < 8 400
Gardner