cas: 13463-67-7 titanium dioxide powder supplier

The skin of an adult person is, in most places, covered with a relatively thick (∼10 μm) barrier of keratinised dead cells. One of the main questions is still whether TiO2 NPs are able to penetrate into the deeper layers of the skin. The majority of studies suggest that TiO2 NPs, neither uncoated nor coated (SiO2, Al2O3 and SiO2/Al2O3) of different crystalline structures, penetrate normal animal or human skin. However, in most of these studies the exposures were short term (up to 48 h); only few long-term or repeated exposure studies have been published. Wu et al.83 have shown that dermal application of nano-TiO2 of different crystal structures and sizes (4–90 nm) to pig ears for 30 days did not result in penetration of NPs beyond deep epidermis. On the other hand, in the same study the authors reported dermal penetration of TiO2 NPs with subsequent appearance of lesions in multiple organs in hairless mice, that were dermal exposed to nano-TiO2 for 60 days. However, the relevance of this study for human exposure is not conclusive because hairless mice skin has abnormal hair follicles, and mice stratum corneum has higher lipid content than human stratum corneum, which may contribute to different penetration. Recently Sadrieh et al. performed a 4 week dermal exposure to three different TiO2 particles (uncoated submicron-sized, uncoated nano-sized and coated nano-sized) in 5 % sunscreen formulation with minipigs. They found elevated titanium levels in epidermis, dermis and in inguinal lymph nodes, but not in precapsular and submandibular lymph nodes and in liver. With the energy dispersive X-ray spectrometry and transmission electron microscopy (TEM) analysis the authors confirmed presence of few TiO2 particles in dermis and calculated that uncoated nano-sized TiO2 particles observed in dermis represented only 0.00008 % of the total applied amount of TiO2 particles. Based on the same assumptions used by the authors in their calculations it can be calculated that the total number of particles applied was 1.8 × 1013 /cm2 and of these 1.4 x107/cm2 penetrated. The surface area of skin in humans is around 1.8 m2  and for sun protection the cream is applied over whole body, which would mean that 4 week usage of such cream with 5 % TiO2 would result in penetration of totally 2.6 × 1010 particles. Although Sadrieh et al.concluded that there was no significant penetration of TiO2 NPs through intact normal epidermis, the results are not completely confirmative.

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At present, the equipment and manufacturing process of domestic manufacturers of polyvinyl butyral are constantly getting closer to those abroad. For example, the wonderful use of polyvinyl butyral (PVB) has occurred in the printing industry and ceramic industry. Therefore, the domestic application of polyvinyl butyral (PVB) has an obvious upward trend in recent years.

For example, in the glass industry, it is because polyvinyl butyral (PVB) has good low-temperature impact strength, windability, light transmittance, light resistance, weather resistance, sound insulation, UV insulation and other properties, so that once the laminated glass is sealed together, the glass sandwich (i.e. laminated material) will appear as a whole and look like ordinary glass. For example, in the porcelain industry, polyvinyl butyral is made into a film and used for printing paper film of ceramic (or enamel) products. First, it reduces the original glue small paper Decal process, reduces the production cycle and production cost, and second, it makes its ceramic (or enamel) patterns bright in color and smooth in texture.

With the rapid development of science and technology in recent years, more and more industries have found the characteristics of polyvinyl butyral (PVB): high strength, high toughness, fatigue resistance, corrosion resistance and so on. Compared with traditional materials, polyvinyl butyral (PVB) is more and more widely used because of its larger development space and wider application fields!

Application field of polyvinyl butyral -- safety glass

The membrane made of polyvinyl butyral (PVB) is a special product used to manufacture safety glass and bulletproof glass. Safety glass is a special glass made of a layer of PVB diaphragm sandwiched between two layers of ordinary glass. It has good low-temperature impact strength, windability, light transmittance, light resistance, weather resistance, sound insulation, ultraviolet insulation and other properties. When subjected to strong external impact, PVB diaphragm can absorb impact energy, so that the glass will not break or prevent debris from hurting people. Moreover, the safety glass added with PVB diaphragm has the characteristics of high transparency, water resistance and aging resistance, and can be used in the environment of - 60 ℃. In addition, it can also be used as transparent material to replace plexiglass.

Application field of polyvinyl butyral -- ceramic film flower paper

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