Nano titanium dioxide powder for cosmetics has many excellent properties, such as safe and non-toxic, can shield ultraviolet rays, high decolorization power (or coloring power), strong hiding power or transparency, good hue, wide color spectrum, etc. The favor of the artist has become the most important and the largest amount of inorganic additives in high-end cosmetics. The following will introduce the application of nano titanium dioxide in cosmetics.

A. sunscreen
1. Mechanism:
Because of its high refractive index and high light activity, titanium dioxide has been used as a main sunscreen agent.
Ultraviolet damage to human body is generally in the mid-wave and long-wave regions.
Titanium dioxide's ability to resist ultraviolet rays is related to its particle size:
When the particle size is large, the blocking of ultraviolet rays is mainly reflection and scattering, and it is effective for ultraviolet rays in the medium and long wave regions. The sun protection mechanism is simple covering, it is a general physical sun protection, and the sun protection ability is weak.
When the particle size is small, the absorption of ultraviolet rays in the mid-wave region is significantly enhanced. Its sun protection mechanism is to absorb ultraviolet rays, mainly absorb ultraviolet rays in the mid-wave region.
It can be seen that the protection mechanism of titanium dioxide for different wavelengths of ultraviolet rays is different, and the long-wavelength ultraviolet rays are blocked to scatter
Because of its small particle size and large activity, nano-TiO2 can reflect and disperse mainly, and it mainly absorbs ultraviolet rays in the mid-wave region.
When it emits ultraviolet rays, it can absorb ultraviolet rays, so that it has a stronger blocking ability to ultraviolet rays.
2. Advantages:
Nano TiO2 is an inorganic component, has excellent chemical stability, thermal stability and non-migration and strong achromatic power, hiding power, low corrosion, good dispersibility, and is non-toxic, odorless, non-toxic It is irritating, safe to use and has the function of sterilization and deodorization.
More importantly, as mentioned above, nano-titanium dioxide can absorb ultraviolet light, and can also emit and scatter ultraviolet light, so it has strong resistance to ultraviolet light.Compared with the same dose of organic anti-UV agent, its absorption peak in the ultraviolet region higher;
Moreover, the nanometer titanium dioxide can block the ultraviolet rays in the mid-wave and long-wave regions, unlike the organic anti-ultraviolet agent which only has a shielding effect on the ultraviolet in the mid-wave or long-wave regions.

3. Example:
Transparent titanium dioxide.
Theoretically, when the crystal particle size is less than 100 nanometers, titanium dioxide loses the scattering power of visible light and becomes transparent titanium dioxide. In order to ensure sufficient transparency, the primary particle size of commercial transparent titanium dioxide is generally controlled at 10-50 nm.
This transparent titanium dioxide is non-toxic, has transparency that reveals the true face of the skin, and has a stronger ultraviolet shielding (absorption of K reflection), which can replace organic ultraviolet absorbers that are suspected of being toxic, and thus is used by cosmetic formulators. What they are optimistic about. Moreover, this titanium dioxide has a strong shielding effect on long-wave (380-320) ultraviolet UV-A medium-wave (320-290) ultraviolet UV-B and short-wave (290-200) ultraviolet UV-C in sunlight.
The synthetic organic ultraviolet absorber can only shield one kind of ultraviolet UV-A or UV-B. In order to improve the dispersibility of this titanium dioxide, it needs to be treated. One method is the surface modification of titanium dioxide with carboxylic acid or siloxane; another method is to prepare a pre-dispersion.
In order to make sunscreen cosmetics closer to the color of the skin and prevent the skin from producing an unhealthy blue appearance due to partial reflection of short-wavelength blue light, foreign countries have developed skin-tone transparent titanium dioxide. There are two kinds of preparation methods: one is to use iron-containing compounds to surface coat the titanium dioxide; the other is to use iron as the dopant to dope the titanium dioxide.

B. Whitening with natural skin tone
Titanium dioxide has extremely low coloring power, and it is made into skin color powder. No additional pigment is needed in the production, which avoids the harm of a large number of pigments to the human body, and also prevents the pigments from being deposited after the cosmetics are left for a long time.
The size of nano titanium dioxide particles is closely related to their ability to resist ultraviolet rays. When the particle size is equal to or less than half of the wavelength of the light wave, the amount of reflection and scattering of light is the largest, and the shielding effect is the best. The wavelength of ultraviolet light is between 190 and 400nm, so the particle size of nano-titania cannot be greater than 200nm, preferably not greater than 100nm. However, it is not that the smaller the particles, the better. If the particle size is too small, it is easy to agglomerate, which is not conducive to dispersion, and it is also easy to block the pores of the skin, which is not conducive to ventilation and the elimination of sweat. Generally speaking, when the particle size is between 30~100nm, the effect of shielding ultraviolet rays is the best.
Because of its fine particles and high transparency of the finished product, it can transmit visible light, and the whiteness of the skin is natural when it is used in cosmetics. It overcomes the opacity of some organic substances or pigment-grade titanium dioxide, which makes the skin appear unnaturally pale.
C. Natural makeup-photochromic titanium dioxide
Photochromism refers to the change of the color of a substance due to light irradiation. Once the irradiation is terminated, the substance returns to its original color.
A trace of iron oxide is added to anatase hydrated titanium dioxide, and calcined in the atmosphere in the range of 750?, 885? to produce photochromic titanium dioxide. This titanium dioxide is used in foundation creams.This cosmetic is applied to the skin. It is a color when exposed to outdoor sunlight, and returns to the interior to become another color, so that it can get a natural makeup effect both indoors and outdoors. .
D. Black pigment-titanium black
The carbon black used in black cosmetics now has the advantages of high blackness and strong coloring power. But it is a hydrophobic substance, which is difficult to disperse in water. It is also reported that it contains 3,42 phenylpropylpyrene and other carcinogens. Japan has begun to use a new black powder pigment, that is, titanium dioxide is reduced to make a low-cost titanium oxide black pigment. Low-cost titanium oxide and titanium oxynitride are collectively called titanium black.
Using high-purity titanium dioxide as raw material, it can be reduced in ammonia gas to obtain black titanium oxide pigment. Because no harmful impurities are brought into the production process, the titanium black prepared by this method is safe and non-toxic, and is suitable for black pigments in cosmetics, such as the production of eyebrow pencils and mascara. The main properties of titanium black: particle size 015Λm, 019Λm, hue L value 8,10, heat-resistant temperature 500?.
E. Mica titanium pearlescent pigment
Mica titanium pearlescent pigments are cherished by cosmetic formulators because they can give people a pearl-like appearance, metal-like flicker and rich changing colors (two-color) effect, plus non-toxic.
The traditional mica titanium pearlescent pigments are silver-white, iridescent, and golden. Currently, silver gray and blue-gray mica titanium pearlescent pigments are developed. Three methods are generally used abroad: (1) On the mica flakes: After depositing a layer of titanium dioxide, Deposit another layer of iron titanate; (2) After depositing a layer of titanium dioxide, deposit another layer containing 0.1% to 1% carbon black; (3) Reduce the first layer of titanium dioxide on the mica to black tone Low-cost titanium oxide, and then deposit a layer of titanium dioxide.
F. Core-coated titanium-containing pigments
In order to prevent the color difference, segregation and staining of solid phases in cosmetics due to the difference in density and particle size, a variety of core-covered pigments have been developed for cosmetics in recent years, including those containing titanium dioxide.
For example, using porous nylon as the mother core and titanium dioxide and iron oxide pigment particles as the child particles, according to a certain ratio, mechanical impact force is used to firmly anchor the two particles to the mother core to form a skin color for cosmetics. Core-coated pigments. The foundation cream made with it and other ingredients does not cause color difference, segregation and stain.

SAT NANO can supply the titanium dioxide powder tio2 powder 30nm, 50nm, 100nm for the cosmetics, if you have any enquiry, please contact us at admin@satnano.com