Author: Wang Xiao
[abstract] the cosmetics market in the 21st century is facing more innovation and technological changes. Consumers hope that cosmetic products not only provide color, but also have conditioning and skin care. With the acceleration of the pace of life, people also hope that make-up products can be used easily and quickly. However, in any case, the performance of the product itself is the most important, they must be glamorous and extremely comfortable, resulting in the emergence of silicone technology, this paper will discuss the application of silicone technology in make-up.
[key words] make-up; silicone; Technical Application
For a long time, makeup gives people the impression of being thick and greasy. Although increasing the amount of organic oil phase can improve the water resistance of makeup, it reduces the comfort of use, resulting in the unnatural appearance of makeup. Obviously, makeup products need to be innovated. With the continuous emergence of advanced raw materials and the continuous improvement of formulation technology, although today's cosmetic products still appear in the form of oil or wax film, they have successfully overcome their original shortcomings, in which silicone with functional groups plays an important role.
I. about organosilicon gel
Silicone gel can be regarded as cross-linked siloxane elastomer gel particles dispersed in carrier fluid, and can be used as an effective rheological thickener for low molecular weight siloxane fluid, which can be added to skin care and make-up products. It can not only provide a mild initial feeling of low molecular weight siloxane fluid, but also provide a sense of film formation, while maintaining the high viscosity of skin care and make-up products.
Some commonly used moisturizers, such as glycerin, will produce a sense of oiliness when added more in skin care products and make-up products, resulting in products that are not easy to distribute and spread to the skin; while panthenol or nicotinamide are added in more amounts in skin care products and make-up products, will produce a sticky feeling. In order to improve the spreadability and pleasure of skin care and cosmetic products, it is generally necessary to add low molecular weight siloxane fluid to give the cosmetic composition a dry, smooth and uniform touch and increase the visual luster. However, while the low molecular weight siloxane fluid gives the required properties to the composition, its volatility and low viscosity make it difficult to retain in the preparation, easy to separate, and may even flow uncontrollably through the skin during use, which limits its application in cosmetic compositions. If common thickeners are used to increase the viscosity of the solution and slow down the evaporation loss of volatile low molecular weight silicone oil, it may reduce the expandability of silicone oil and leave a serious sense of slippery skin. Silicone gel for cosmetics can be regarded as an effective thickener for low molecular weight siloxane fluid, providing unique skin sensation such as dryness and silkiness, so it has become a potential daily chemical raw material and has a good market application prospect.
Second, the specific application mechanism of organosilicon technology in color makeup.
Organosilicon compounds react to form a polymer cross-linking network, and the gaps in the cross-linking network are filled with solvent molecules, and the resulting dispersion system is called silicone gel, which shows a unique dry and silky skin feeling due to the interaction between the cross-linking network and the solvent. The mechanism of silicone gel providing good skin sensation is similar to the process of sponge water absorption. The cross-linked network of silicone gel is swollen with solvents, and the solvent molecules are filled with the gaps between the cross-linked networks, so that when smearing, it can not only provide the light and smooth feeling of the skin as a solvent, but also have a sense of film formation related to the structure of the cross-linking network itself after the solvent is absorbed or volatilized.
The skin sensation of silicone gel is determined by the interaction of cross-linking network and solvent. Through the combination of different cross-linking systems and different solvents, silicone gel can be prepared to provide various skin sensations such as dryness, silky, powdery and moisturizing for skin care and makeup products. The common cross-linking systems of silicone gels for cosmetics are generally formed by hydrosilylation of high molecular weight polysiloxanes containing Si-H bonds and compounds containing unsaturated alkyl groups such as dienes and diynes under the action of hydrosilylation catalysts. A three-dimensional cross-linking network is formed by hydrosilylation reaction, which is characterized by no formation of by-products and can accurately define the cross-linking points and the resulting network structure. Common solvents for silicone gels include low molecular weight straight-chain or cyclic siloxanes, organic solvents, mixtures of low relative molecular weight straight-chain or cyclic siloxanes and organic solvents. [1] the cross-linking network and the solvent used determine the properties and skin feel of the silicone gel through their interaction, but the structure of the cross-linking network has a greater influence.
On the other hand, silicone gels are widely used in lipstick, foundation, shampoo, hair conditioner, hair styling agent, bath gel, moisturizer, sunscreen, antiperspirant and deodorant formulations because of their unique sensory properties, reducing stickiness of formulations and increasing visual gloss of products. The polyglyceride siloxane elastomer obtained by the reaction of hydrogen-containing polysiloxane and polyglyceride containing double bond in the presence of platinum catalyst can increase the stability of cosmetic composition containing silicone oil. The addition of silicone elastomer emulsion containing MQ silicone resin to the personal care composition improves the film properties of the personal care composition on the skin and hair and makes the composition easy to prepare. The introduction of appropriate silicone gel into deodorant or antiperspirant can provide a smooth skin feel and reduce the possibility of dehydration and shrinkage of the product. Silicone gel containing MQ silicone resin and C18 or stearyl side chain can not only form high strength continuous film with good adhesion after carrier solvent volatilization, improve the spreading performance of pigments and other granular active matter, effectively reduce the agglomeration of inorganic sunscreen in sunscreen products, but also have good anti-migration performance, which is beneficial to its application in color makeup formula.
III. Conclusion
With the increasing refinement of personal care products and the increasing demands of consumers for them, not only are care products required to have good efficacy, but they are also expected to provide a good skin feel and a pleasant appearance. Silicone gels are widely used in personal care products due to their unique skin feel and thickening properties. By trying more different types of cross-linking systems and different solvents to prepare silicone gels with different skin feels, improving the compatibility and aesthetic properties of silicone gels with other components in personal care product formulations has become a development trend. At the same time, improving the preparation process of silicone gels, simplifying the production process, and reducing production costs are also a research direction for silicone gels for cosmetics in the future.
On the other hand, there are many silicone raw materials that are used in cosmetics. For example, silicone polyether increases the hydrophilicity of silicone by introducing polyoxyethylene or polyoxypropylene substituents into the silicone backbone, making it a hydrophilic-lipophilic balance modifier to form a unique water-in-silicone oil system. This system has excellent water resistance, easy to spread and non-greasy and suitable for liquid foundations. [2]Another example is phenyl silicone oil, which has a high refractive index and high organic compatibility, and has a smooth and non-greasy skin feeling. It is widely used in cosmetics, especially lipstick. Other applications include the treatment of powders by organic silicon, etc. With the improvement of makeup formulation technology and product performance, silicones will have a broader application prospect.
References:
[1]General Electric Company. Elastomeric gels containing volatile low molecular weight silicones: CN, 1177615A[P]. 1998.
[2]Wacker Chemical GmbH. Organopolysiloxane gels for cosmetics: CN, 1275369A[P]. 2000.
