Formulating moisturising products Emollients –An emollient is a material which, when applied to the skin makes it feel soft and smooth. Humectants –These exhibit hygroscopic behaviour, they can draw in and hold onto large amounts of water.
What makes a good moisturiser? You need to understand the skin type you are formulating for. You need to understand target area It should feel nice on application, not too greasy. It shouldn’t ‘soap up’ It should smell nice, or have no base odour
Product formats Roll-on – good skin contact, efficacy »Might pull your hair, longer drying time Aerosol – quick drying time »Hygienic Stick - good skin contact, efficacy »Poor hygiene profile Cream – excellent skin contact »messy
Efficacy testing Olfactory Sniff test – trained noses Gravometric Controlled conditions Weighing the amount of sweat At least 20% reduction in sweat levels in treated versus untreated
5 May Sun protection
Suncare products How does sunlight affect the skin? –Tanning through darkening of melanin precursors –Skin damage – sunburn, premature ageing, skin cancer Free radicals
UVA & UVB light UVA – ( nm) Responsible for long term damage Can penetrate glass UVB – ( nm) Causes sunburn (erythema)
Sunscreens A Sunscreen is the UV light absorbing agent that helps to lower the incidence of dermal malignancies. The function of the sunscreen is the protection of the skin from damaging UV light. Physical sunscreens Chemical Sunscreens
SPF calculations and star rating SPF = Time to produce erythema in protected skin Time to produce erythema in unprotected skin Star Rating = mean UVA/UVB ratio –0 to <0.2too low to make UVA claim
5 May Hair Removal
How do we remove hair? Mechanical –Tweezing –Threading –Electrical epilation –Electrolysis –Sugaring –Waxing –Shaving Chemical –Thiglycollates –Enzymes
Epilation & Depilation Epilation – is a process of hair removal from below the skin’s surface Depilation – is a process of the temporary removal of hair from the surface of the skin.
Depilatories Thyoglycollate –Work by breaking the disulphide linkages in the keratin hair fibres, and totally disintegrate the hair Enyzme based –These contain protein-digesting enzymes (papain is a good example. Treat the empty hair follicle to reduce hair growth over a number of months