Skin Care & Cosmetics Ingredient Glossary (T-Z)

Tea Tree Oil

Tea tree oil has been shown to have anti-inflammatory, antimicrobial, antifungal, antiseptic, and antiviral properties. This essential, clarifying oil helps relieve redness, swelling and inflammation, and is also effective in reducing acne-causing bacteria and healing infections.

Korean skin care products with tea tree: Some By Mi AHA BHA PHA 30 Days Miracle Toner and The SAEM Natural Tea Tree Mask Sheet.

*Synonym: Melaleuca Alternifolia

Tyrosine 

Tyrosine is a non-essential amino acid found in the body that supports the production of melanin and improves both collagen breakdown and skin pigmentation.

When combined with L-ascorbic acid (vitamin C), tyrosine simulates fibroblast activity to increase collagen production, making it an excellent choice for anti-aging products.

It is widely used in wrinkle creams, eye creams and serums, as well as sunscreens, facial moisturizers and makeup concealers. 

Vitamin C 

Vitamin C is a potent antioxidant that stimulates collagen production, protects skin from UV damage, fades dark spots and smooths fine lines.

This powerhouse ingredient is well-known for its anti-aging effects and skin brightening properties, making it ideal for people with dull and uneven complexions.

If you have sensitive skin, we recommend starting with a lower concentration, as you may experience allergies or redness with higher concentrations of vitamin C.

You'll love theses vitamin C bombs — Liz K Super First C Serum Pure Vitamin 13%, La Roche-Posay Vitamin C Serum, Nature Republic Real Comforting Mask Sheet, and Paula's Choice Resist C15 Super Booster.

(Related blog post: What Are Vitamin C Benefits in Skin Care?)

*Synonym: Ascorbic acid, L-Ascorbic acid, Calcium Acerbate, Sodium Ascorbyl Phosphate, Ascorbyl Palmitate, Vitamin C Palmitate, Sodium Ascorbate, Aminopropyl Ascorbyl Phosphate, 3-O Ethyl Ascorbic Acid, Tetrahexyldecyl Ascorbate, Ascorbyl Tetraisopalmitate, Magnesium Ascorbyl Phosphate, Calcium Ascorbate, Ascorbyl Tetraisopalmitate, Vitamin C Ester, Ascorbyl glucoside.

Vitamin E (Tocopherol)

Vitamin E is an oil-soluble antioxidant that may help protect your skin cells from free radical damage and slow the aging process.

Vitamin E comes in eight different forms, and when it comes to skin care products, tocopherol and tocopheryl acetate are the ones you'll find in most ingredient lists.

Certain types of vitamin E also have anti-inflammatory properties that help soothe redness and inflamed skin. Vitamin E may lighten dark spots and acne scars and can be used as an anti-aging cream for people with fine lines and wrinkles.

Here are products containing Vitamin E: Urang Brightening Blue Oil Serum, Urang Vitamin Oil Serum, and Olivarrier PH 5.5 Dual Moist Hyaluron Essence.

*Syn: D-Alpha-Tocopherol, D-Alpha-Tocopherol Acetate, Dl-Alpha Tocopherol, Dl-Alpha Tocopherol Acetate

Titanium Oxide (TiO2) 

Titanium oxide is a naturally occurring mineral found as a UV filter and/or colorant/whitener in a variety of cosmetics and personal care products, including sunscreens, pressed powders, loose powders (or "mineral powders"), lotions, toothpastes, and soaps.

Titanium oxide is classified as a physical sunscreen agent that protects the skin from both UVA and UVB radiation, preventing sunburn and premature aging. It leaves a barrier on the surface of the skin and is not absorbed by the skin.

TiO2 is considered safe for our skin because it is gentle and poses no risk of sensitivity, which is why it is suitable for all skin types, including sensitive and redness-prone skin. 

*Syn: Titanium(IV) Oxide, Titania

Witch Hazel 

Witch hazel, derived from the bark and leaves of the witch hazel shrub, is a natural astringent with antiseptic and anti-inflammatory properties that may help relieve inflammation, tighten pores, remove excess oil, and reduce acne.

However, witch hazel may be irritating or cause allergic reactions because it is derived from botanical sources. Also, it should be noted that some studies have shown that excessive use of witch hazel in large amounts can have constricting, drying, and sensitizing effects on the skin.

*Syn: Hamamelis Virginiana

Wintergreen Oil

Wintergreen is a type of mint herbs known for its analgesic (pain-relieving) and astringent properties that may relieve muscle pain, improve complexion clarity and soothe irritation. 

Methyl salicylate is the main constituent in wintergreen oil, which has anti-inflammatory properties but can be sensitizing on the skin and is pharmacologically similar to aspirin, so stay away from this essential oil if you are allergic to aspirin.

*Syn: Gaultheria Procumbens 

Willow Bark 

Willow bark contains salicin, from which salicylic acid is derived, also known as beta-hydroxy acid (BHA). Willow bark has keratolytic properties, meaning it sloughs off dead skin cells from the upper layers and cleanses pores, revealing newer, younger-looking cells.

An extract of willow bark is a lipophilic plant compound that helps control excess sebum and future oil production - which may have clogged pores and led to blackheads, whiteheads and breakouts.

Salicylic acid also has anti-inflammatory, analgesic, soothing and antibacterial properties and is ideal for oily, combination and blemished skin.

Since salicylic acid can increase the skin's sensitivity to the sun, use a broad-spectrum sunscreen with an SPF of at least 30 to avoid burns, age spots, and increased risk of skin cancer.

Here are Korean beauty products with willow bark—Cosrx One Step Original Clear Pad, Pyunkang Yul Acne Toner, and Isntree Green Tea Fresh Toner.

*Synonym: Salix Alba

Zinc Oxide

Zinc oxide is a natural mineral that acts as a physical sub-block, providing UVA and UVB broad spectrum sun protection. Unlike chemical sunscreens, zinc oxide sits on the surface of the skin like a shield and scatters light. 

Zinc oxide is known for its non-irritating and non-comedogenic properties, and is gentle enough to be used for sensitive and acne-prone skin types. The skin protectant helps heal, repair and treat skin irritations such as rashes, cracked skin, minor burns or abrasions.

Mineral sunscreens are usually thicker than chemical sunscreens and leave an unsightly white cast. Today, thanks to constant product innovation, improvement and refinement, many formulas with physical sunscreens no longer leave an undesirable white cast.

Here are some Korean sunscreens with zinc oxide—Neogen Dermalogy Day-Light Protection Sunscreen SPF 50 PA+++, Dr. G Brightening Up Sun Cream SPF50+ PA+++ and Purito Comfy Water Sun Block SPF50+ pa++++ .