The ingredients in hand creams and general skincare creams are fundamentally similar; they can be broadly categorized into four main groups: aqueous-phase ingredients, oil-phase ingredients, emulsifiers, and other components.
Oil-Phase Ingredients
1. Hydrocarbons: Squalane, mineral oil, petrolatum, paraffin wax, etc.
2. Natural Oils/Fats: Olive oil, avocado oil, almond oil, apricot kernel oil, corn oil, wheat germ oil, evening primrose oil, etc.
3. Higher Fatty Acids: Stearic acid, palmitic acid, lauric acid, myristic acid, oleic acid, isostearic acid, isostearyl alcohol, etc.
4. Higher Fatty Alcohols: Cetyl alcohol, stearyl alcohol, cetearyl alcohol, oleyl alcohol, cholesterol, etc.
The primary functions of the above four categories of ingredients are to impart softness and lubricity to the skin; to facilitate the skin's absorption of medications and active ingredients; to form a hydrophobic oil film; to moisturize the skin; to inhibit moisture evaporation; to reduce friction; to enhance skin luster; and to assist in cleansing the skin.
5. Waxes: Beeswax, lanolin, carnauba wax, candelilla wax, jojoba wax, paraffin wax, microcrystalline wax, etc.
Wax ingredients primarily serve as solidifying agents to enhance product stability; to impart rheological properties and thixotropic effects; to improve the sensory experience and emollient effects; to raise the melting point of the oil phase; to reinforce the hydrophobic film on the skin's surface; and to give the product a glossy finish.
6. Synthetic Esters: IPM (Isopropyl Myristate), IPP (Isopropyl Palmitate), Caprylic/Capric Triglyceride, Isostearyl Neopentanoate, Pentaerythrityl Tetraisostearate/Tetracaprate/Tetracaprylate, Oxalates, Pentaerythrityl Stearate, Dicaprylyl Carbonate, Dicaprylyl Ether, etc.
Synthetic esters primarily function as emollients, improving the product's spreadability, lubricity, moisturizing capabilities, and breathability; they also aid in the wetting and dispersion of powders and pigments, serve as solvents for oil-soluble components and waxes, and enhance the overall skin feel of the product.
7. Others: Dimethicone, Cyclopentasiloxane, Cyclomethicone, etc.
Aqueous Phase Ingredients
1. Humectants: Glycerin, Propylene Glycol, 1,3-Butylene Glycol, Polyethylene Glycol, Sorbitol, Dipropylene Glycol and its derivatives, Amino Acids, Lactic Acid and Sodium Lactate, Sodium PCA, Methyl Gluceths, Panthenol, Chitin derivatives, etc.
Their functions include moisturizing the stratum corneum, improving sensory feel, and solubilizing water-soluble ingredients.
2. Water-soluble Polymers: Xanthan Gum, Guar Gum and its derivatives, Alginates, Hydroxyethyl Cellulose, Carbomer, Acrylamide/Sodium Acryloyldimethyltaurate Copolymer, Aluminosilicates, etc.
They serve as co-emulsifiers; provide dispersion and suspension effects to enhance stability; regulate rheology; improve sensory feel; and offer moisturizing benefits.
3. Water-soluble Lipids: Ethoxylated Triglycerides, Di-PPG-3 Myristyl Ether Adipate, PEG-40 Castor Oil, PEG-60 Almond Glycerides, PEG-42 Babassu Glycerides, etc.
They act as solubilizers and co-emulsifiers in O/W systems; they regulate product viscosity and improve the product's skin feel.
4. Low-carbon Alcohols: Ethanol, Isopropyl Alcohol.
They are capable of solubilizing other ingredients and regulating viscosity.
5. Water.
Emulsifiers
The primary function of emulsifiers is to facilitate the emulsification of the lotion system and to adjust the system's HLB value.
Other Components
1. Alkalies/Bases: Potassium Hydroxide, Sodium Hydroxide, Triethanolamine, Aminomethyl Propanol. (Used for pH adjustment.)
2. Preservatives: Methylparaben and Propylparaben, Imidazolidinyl Urea, Polyquaternium-15, Benzoic Acid, etc. (Primarily serve an antibacterial function.)
3. Antioxidants: BHT, BHA, α-Tocopherol, Ascorbyl Esters, etc. (Inhibit and prevent product oxidation.)
4. UV Absorbers: Benzophenone-5, Ethylhexyl Methoxycinnamate. (Protects the product from UV exposure)
5. Chelating Agents: Disodium EDTA
6. Buffering Agents: Citric Acid–Sodium Citrate, Lactic Acid–Sodium Lactate (pH adjustment)
7. Coloring Agents
8. Fragrances and Perfumes
9. Pharmaceutical Agents and Active Ingredients