Skin and Skin Care Products

The Skin Encloses the body Prevents some internal materials from escaping Keeps most external materials out Regulates body temperature Regulates penetration of sunlight

Layers of the skin The skin has many components, but it can be considered as four layers Subcutaneous tissue Underlying fatty material Dermis True skin Epidermis Outer layer Stratum Corneum

Only skin deep?

Stratum Corneum Outer most layer of the skin Approximately 10µm thick About 20 layers of dead cells Composed primarily of keratin (protein) Overlap like shingles Continually sloughed away Cannot be penetrated by water soluble materials. Can be destroyed by acid or caustic.

Epidermis Replenishes the stratum corneum Contains the pigment producing cells that determine skin color.

Dermis Contains the working elements of the skin: Sensory nerves Hair follicles Blood vessles Sweat glands Sebaceous glands Excrete sebum 50% fat 20% wax 5% free fatty acids

Skin Types Normal – soft smooth skin with a healthy appearance Oily – shiny with enlarged pores. Often blemished Dry – fine texture, flaky, many expression lines, poor elasticity Sensitive – florid with broken capillaries, fine textured, like dry skin Blemished – excessively oily with blemishes

Skin care Cosmetics Moisturizers Cleansing creams and lotions Cleansers for oily skin Lighteners Anti-aging Acne Sunscreen Self tanner

Moisturizers A product that adds water, and often some emollients, to the skin. A variety of types of moisturizers are available (for various skin types), and are necessary for all skin types to prevent dehydration. Replaces water lost from the skin Dryness and flexibility cannot be corrected with oils - Only Water Oil is used to limit the evaporation of water. Formulation ingredients

Common Ingredients Humectants Emolients Occlusives Actives Fragrance

Humectants An ingredient in skin or hair products that draws moisture from the air to moisturize the skin and also promotes the retention of moisture in the skin Examples: Glycerine Propylene glycol Sorbitol Urea Lactic acid Hyaluronic Acid

Emolients Supple, waxlike, lubricating, thickening agents that prevent water loss and have a softening and soothing effect on the skin. A skin conditioning agent which helps maintain the smooth, soft pliable appearance of the skin. usually a grease or an oil that softens the skin and protects it from dryness.

Emolients Examples Sunflower seed oil Allantoin Cocoa butter Olive oil Mineral oil Myristyl Myristate

Occlusive substances that hold strongly to the surface of the skin, preventing access to the air and increasing absorption of cosmetic treatments. Usually refers to an occlusive shield or film that is spread onto the skin to slow or prevent moisture evaporation.

Occluives Examples Petrolatum Lanolin Candililla wax dimethicone

Actives – Anti aging Alpha Hydroxy Acid Any one of several natural acids (glycolic, lactic, citric, malic) obtained from fruit which assist in shedding dead skin cells. They provide the benefit of chemical exfoliation of the skin, making skin appear clearer.

Actives - Acne Benzoyl Peroxide - An oxygen releasing chemical which causes drying, peeling and antibacterial action on the skin. Used for acne lesions, benzoyl peroxide is the number one acne medication recommended by doctors.

Actives – sunless tanning Dihydroxyacetone - The active ingredient of sunless tanning products, reacts with amino acids in the outer layers of the skin to produce a browning effect.

Actives – skin lightening Kojic acid is primarily used in cosmetics for it's skin lightening effect. It acts as an inhibitor of tyrosinase, which is responsible for the formation of melanin - the skin coloring agent in skin. hydroquinone. Substance that is known to successfully reduce the intensity of freckles, melasma, and general brown patching by inhibiting melanin production. For continued and increased effectiveness it must be used long term.

Actives - sunscreens Zinc oxide - an opaque, full-spectrum sunscreen also used to give opacity to face powder and foundation. Titanium dioxide - a full-spectrum , which means that it protects the skin from both UVA and UVB rays. It is also used to give opacity to face powder, eye shadow, and foundation.

Actives – anti-dandruff Zinc pyrithione - a strong anti-dandruff ingredient that is both a bactericide and fungicide. It can be irritating to the skin.