cosmetic chemistry Flashcards
Cosmetics
-articles that are intended to be rubbed, poured, sprinkled
or otherwise applied to the body for cleansing,
beautifying, promoting attractiveness or altering the
appearance
Functional ingredient
- allow products to spread, give them body and texture
- vehicles
Performance ingredients
- cause an actual change in skin
- referred to by their activity
- active or key ingredients
water as an ingredient
both a vehicle (functional) and a performance
as vehicle = helps keep ingredients in solution and helps to spread
as performance = water replenishes moisture
Emulsions
- mixture of oil and water
- found in almost all cosmetic products
oil in water emulsion
- most common
- oil in mostly water
water in oil emulsion
-water in a base of mostly oil
anhydrous products
- products that do not contain any water
- oil serums
- silicone serums
- petroleum based products
Emmollients
- Almost always fatty agents
- natural or synthetic
- oils, fatty esters, fatty alcohols, fatty acids, silicone, waxes
As vehicle = place, spread and help keep other agents on the skin
As performance = lubricate, create a seal that prevents dehydration by trapping water to increase moisture in the epidermis
lanolin
- emollient
- animal fats
- sheep skin secretion
fatty esters
-emollient
-from fatty acids and alcohols
-almost always end in a-t-e
-often feel better than natural oils and have better ability
to lubricate evenly
fatty acids
-emollient
-lubricants derived from triglycerides (plant oils or anilmal
fats)
-give cream soft feel, smooth texture, help other products
adhere to skin
ex, stearic acid, oleic acid, lauric acid, palmitic acid
fatty alcohols
-fatty acids exposed to hydrogen
-not drying like other alcohols such as isopropyl
-
silicones
-derived from minerals
-provide excellent protection but also allow oxygen in and
out of follicles
-no greasy feel and often used in “oil free products”
mineral oil and petroleum
-come from the earth
-non reactive and biologically inert (do not react with other
chemicals involved in the skins function)
-can be used without preservatives because they do not
harbour bacteria or other organisms
surfactants
-chemicals that reduce surface tension between the skins
surface and the product.
-increase spreadability
2 types:
detergent and emulsifiers
Detergents
- type of surfactant
- primarily used in cleaning products
- reduce surface tension of oil and dirt on skins surface
- helps lift oil and dirt off the skin
- cause cleansers to foam
- if too strong or in too large concentration they can damage lipid barrier function of skin
- can cause skin to feel dry
products from base to least
base product = water and oil and emulsifier emollient preservatives thickeners/texturizers pH factors - buffering agents hydrating agents fragrance/colour/essential oils
examples of detergents
lauryl sulfate or sodium lauryl sulfate (good cleanser but an irritant)
Emulsifiers
keep oils and water blended in a product
(they surround oil particles allowing them to stay
distributed throughout the water)
added to the oil or water phase
oil soluble
Materials compatible with oil are mixed in with the oil.
They are mixed into the oil phase of the product.
water soluble
substances that compatible with and water are mixed into the water phase of the product
Preservatives
work to prevent bacteria and other microorganisms from living in the product
-are either toxic or release substances that are poison to the microorganism
-some protect products from chemical change
ex, antioxidant
Antioxidant as preservative
- protect product from chemical changes (functional)
- inhibit oxidation or reactions promoted by oxygen or peroxides
- work by chemically stopping free radicals from attacking oils in product
- also work to help condition of the skin (performance)
- used with microencapsulation which prevents antioxidant from neutralizing before it gets onto skin and helps penetrate the skin more easily
ex. Vitamins A, C, E
Benzoic acid *
