Classification of Oily Raw Materials

Oily raw materials are used in large quantities in cosmetic formulations, and there are three forms of liquid, semi-solid and solid at room temperature. Under normal circumstances, the oily raw material that is liquid at room temperature can be called "oil", the semi-solid can be called "fat", and the solid can be called "wax". Therefore, the oily raw materials in cosmetics can also be called oil, fat, wax raw materials.

Science knowledge of cosmetic raw materials · Function and classification of oily raw materials

The role of oil-based raw materials in cosmetics

● Barrier action

Oily raw materials can form a hydrophobic film on the surface of the skin, which can reduce the evaporation of water on the skin surface and prevent skin cracking and other conditions, so as to protect the skin barrier and effectively resist the physical, chemical and biological stimulation from the external environment.

● Moisturizing effect

The most basic and important function of oily raw materials is to moisturize the skin, so it is also called emollient. The proper use of oily raw materials helps to maintain the softness, lubrication, elasticity and luster of skin and hair.

● Cleaning function

According to the principle of similarity and dissolution, the use of oily raw materials can make the oily dirt on the surface of the skin easier to clean.

● Solvent action

Oily raw materials can be used as carriers for certain nutrients and conditioning substances, making the ingredients more easily absorbed by the skin.

● Emulsification

Some oily raw materials can be used as emulsifiers, play the function of surfactants, reduce the interfacial tension of each component in the mixing system during the emulsification process, and make the emulsion more stable. Advanced fatty acids, fatty alcohols, phospholipids and other oily raw materials are commonly used as emulsifiers in cosmetics production.

● Curing effect

The appropriate addition of oil-based raw materials in cosmetic formulations can also make product performance and quality more stable.

Classification of oily raw materials

Oily raw materials can be classified in a variety of ways. The most common is according to the state of the substance at room temperature, the oily raw materials are divided into solid, semi-solid and liquid. Among them, solid oil raw materials include stearic acid, cetyl alcohol, beeswax and paraffin, etc. Semi-solid including mineral grease (petroleum jelly), palm oil, palm kernel oil, coconut oil and avocado butter; Liquids include olive oil, almond oil, corn oil, polydimethylsiloxane and dioctyl carbonate.

Sources of oily raw materials mainly include plant, animal, mineral and chemical synthesis. Among them, the oily raw materials of plant origin mainly come from plant seeds and fruits, but also partly from the leaves, skins, roots, petals and stamens of plants, such as corn oil, olive oil, safflower oil, sweet almond oil, palm oil and avocado oil; Oil-based raw materials of animal origin include lanolin, beeswax, whale wax, mink oil, squalane and turtle oil; Common mineral sources of oily raw materials are mineral grease, paraffin, etc. Chemical synthesis of oily raw materials include silicone oil, silicon wax, esters (such as caprylic acid/caprylic acid triglyceride, dioctyl carbonate).

According to the different chemical composition, oily raw materials can be divided into hydrocarbons (hydrocarbons), triglycerides, siloxanes and synthetic esters. Among them, hydrocarbons (hydrocarbons) are cost-effective and easy to spread to form transparent films, mainly including isododecane, isocetane, polyisobutene, etc. Most animal and vegetable oils belong to the triglyceride group; Siloxane oily raw materials have very low surface tension, so they show better spreading and film formation, such as polydimethylsiloxane, cyclic polydimethylsiloxane, etc. The synthetic ester has good lubricity, and the skin feels refreshing, which can be used to reduce the greasy feeling of other oily ingredients, mainly including caprylic acid/caprylic acid triglyceride, dioctyl carbonate and so on.

Oily raw materials can also be divided into light, medium and heavy according to skin sensation. Lightweight oil-based raw materials can spread quickly, effectively reduce the application time, and can provide a strong sense of moisture and a lighter skin feeling; Medium oily raw materials have a longer spreading time and a thicker skin feeling. Heavy oil-based raw materials take longer to spread and have a stronger viscosity and thicker skin feel.

In addition, the spread of different oily raw materials is also different. Oily raw materials that can be quickly spread, such as light silicone oil, etc., have the characteristics of rapid penetration, low greasy feeling, fresh and dry skin feeling, etc., which can bring a relatively short skin feeling; Oily raw materials that need to be slowly spread, such as mineral grease, etc., have a slower penetration rate and a more durable skin feeling, but a heavier sense of greasy.