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CHINESE WHITE

Chinese white is an inorganic compound with the formula ZnO, known for its bright, opaque white color and excellent covering power in traditional Chinese painting.
Chinese white is a safer alternative to lead white, with a smooth texture and quick-drying properties, making it ideal for use in both water-based and oil-based media.
Beyond art, Chinese white is widely used in cosmetics for its UV-filtering properties, as well as in other industries like plastics, ceramics, and electronics due to its versatile characteristics.

CAS Number: 1314-13-2
EC Number: 215-222-5
Chemical Formula: ZnO
Molecular Weight: 81.38 g/mol

Synonyms: ZINC OXIDE, 1314-13-2, Zinc White, oxozinc, Amalox, ZnO, Chinese White, Snow white, Emanay zinc oxide, Felling zinc oxide, Zinc oxide (ZnO), Akro-zinc bar 85, Zinc monoxide, Flowers of zinc, Azo-33, Outmine, Supertah, Zincite, Zincoid, Azodox, Ozide, Ozlo, Zincum Oxydatum, Zinci Oxicum, Zinci Oxydum, Flores de zinci, Hubbuck's White, Blanc de Zinc, Unichem ZO, Vandem VAC, Vandem VOC, çinko oksit, Vandem VPC, Green seal-8, Philosopher's wool, White seal-7, K-Zinc, Powder base 900, Protox type 166, Protox type 167, Protox type 168, Protox type 169, Protox type 267, Protox type 268, Akro-zinc bar 90, Azodox-55, Azodox-55TT, Red Seal 9, EMAR, CI Pigment white 4, Electrox 2500, Actox 14, Actox 16, Kadox 15, Kadox 72, Kadox-25, Zinc oxide [USAN], Zinca 20, Protox 166, Protox 168, Protox 169, Caswell No. 920, Electox 2500, Cadox XX 78, Actox 216, Cynku tlenek [Polish], Nogenol, C-Weiss 8 [German], Azo-55TT, Azo-66TT, Azo-77TT, çinko oksit, Zinc gelatin, C.I. Pigment White 4, RVPaque, Azo 22, Azo-55, Azo-66, Azo-77, No-Genol, Pigment white 4, C.I. 77947, Dome Paste Bandage, A&D Medicated Ointment, XX 78, EINECS 215-222-5, XX 203, XX 601, EPA Pesticide Chemical Code 088502, ZN-0401 E 3/16'', Lassars Paste, Zinc oxide, ACS reagent, Lassar Paste, Zinc oxide, 99.5+%, ZNO, Desitin, zincum oxidatum, Cynku tlenek, oxyde de zinc, Zinc oxide fume, Zinc oxide substrate, 10x10x0.5mm, polished two sides, 0001 orientation, Zinc oxide, 99.99% trace metals basis, C-Weiss 8, Zinc oxide, 99.999%, (trace metal basis), Zinc oxide [USP], Zinkoxid, oxido de cinc, Leaded zinc oxide, Zinc (as oxide), Zinc Oxide Powder, Zinc oxide (TN), Zine Oxide ,(S), Zinc (as zinc oxide), EC 215-222-5, Zinc oxide (JP17/USP), Zinc oxide, LR, >=99%, Zinc oxide, analytical standard, Zinc Oxide Nanopowder (Type I), Zinc oxide, p.a., 99.0%, Zinc Oxide Nanopowder (Type II), 9015AF, Zinc oxide, USP, 99-100.5%, Zinc Oxide Nanoparticles / Nanopowder, Zinc oxide, ACS reagent, >=99.0%, Zinc oxide, 30nm, 20 wt.% isopropanol, Zinc oxide, tested according to Ph.Eur., Zinc oxide, 99.999% trace metals basis, Zinc oxide, SAJ first grade, >=99.0%, Zinc oxide, JIS special grade, >=99.0%, Zinc oxide, nanopowder, <100 nm particle size, çinko oksit, Zinc Oxide Nanodispersion Type A-Nonionic (70nm), Zinc Oxide Nanodispersion Type B-Anionic (70nm), Zinc Oxide Nanodispersion Type C-Cationic (70nm), Zinc oxide, nanowires, diam. x L 90 nm x 1 mum, Zinc oxide, nanowires, diam. x L 50 nm x 300 nm, Zinc oxide, nanowires, diam. x L 300 nm x 4-5 mum, Zinc oxide, puriss. p.a., ACS reagent, >=99.0% (KT), Zinc oxide, nanopowder, <50 nm particle size (BET), >97%, Zinc oxide, ReagentPlus(R), powder, <5 mum particle size, 99.9%, Zinc oxide, United States Pharmacopeia (USP) Reference Standard, Zinc oxide substrate, 10x10x0.5mm, polished one side, 0001 orientation, Zinc oxide sputtering target, 76.2mm (3.0in) dia x 3.18mm (0.125in) thick, Zinc oxide sputtering target, 76.2mm (3.0in) dia x 6.35mm (0.250in) thick, Zinc oxide, dispersion, nanoparticles, <110 nm particle size, 40 wt. % in butyl acetate, Zinc oxide, dispersion, nanoparticles, 40 wt. % in ethanol, <130 nm particle size, Zinc oxide, dispersion, nanoparticles, <100 nm particle size (TEM), <=40 nm avg. part. size (APS), 20 wt. % in H2O, Zinc oxide, puriss., meets analytical specification of Ph. Eur., BP, USP, 99-100.5% (calc. for dried substance), Zinc oxide, sputtering target, diam. x thickness 3.00 in. x 0.125 in., 99.99% trace metals basis.

Chinese white is a historically significant pigment that has been used in various art forms, particularly in traditional Chinese painting.
Composed mainly of Chinese white, it is known for its bright, opaque white appearance and excellent covering power.

Unlike lead white, another common white pigment, Chinese white is less toxic and more stable, making it a safer choice for artists and craftsmen.
Chinese white has a smooth texture and a subtle sheen, allowing for versatile applications in both water-based and oil-based media.

In Chinese painting, Chinese white is often utilized to create highlights and accents, lending a sense of luminosity to artworks.
Chinese white's opacity allows it to be used effectively for mixing with other colors, resulting in a broad palette for artists.
Chinese white's ability to retain its color integrity over time makes it ideal for artworks intended for longevity.

Chinese white is also appreciated for its ease of use and ability to dry quickly, which aids in layering techniques.
Additionally, Chinese white has found applications beyond painting, such as in cosmetics, where it serves as a base for products like face powders and sunscreens due to its UV-filtering properties.

Despite the rise of synthetic alternatives, Chinese white remains a favored choice among artists seeking a natural, traditional medium.
Chinese white's historical roots and aesthetic qualities contribute to its enduring popularity in both fine arts and crafts.

Chinese white is an inorganic compound with the formula ZnO.
Chinese white is a white powder that is insoluble in water.

Chinese white is used as an additive in numerous materials and products including cosmetics, food supplements, rubbers, plastics, ceramics, glass, cement, lubricants, paints, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, and first-aid tapes.
Although Chinese white occurs naturally as the mineral zincite, most Chinese white is produced synthetically.

Chinese white is a wide-band gap semiconductor of the II-VI semiconductor group.
The native doping of the semiconductor due to oxygen vacancies or zinc interstitials is n-type.

Other favorable properties include good transparency, high electron mobility, wide band gap, and strong room-temperature luminescence.
Those properties make Chinese white valuable for a variety of emerging applications: transparent electrodes in liquid crystal displays, energy-saving or heat-protecting windows, and electronics as thin-film transistors and light-emitting diodes.

Chinese white is a versatile and historically significant pigment that has played a crucial role in the evolution of art, particularly within traditional Chinese painting.
Made primarily of Chinese white, it is celebrated for its bright, opaque white color and excellent covering power.
Chinese white has a smooth, velvety texture that contributes to its ability to create luminous highlights and enhance the depth of colors in artwork.

The origins of Chinese white date back to ancient times, where it was used by Chinese artists to depict intricate landscapes and delicate figures.
Unlike other white pigments, such as lead white, which is highly toxic and can cause severe health issues, Chinese white is much safer to use, making it a favored choice among artists and craftsmen throughout the centuries.
Chinese white's stability and resistance to discoloration ensure that artworks retain their vibrancy over time, making it a reliable pigment for both contemporary and traditional techniques.

In terms of application, Chinese white can be used in both water-based and oil-based media.
Chinese white's opacity allows it to serve as an effective mixing color, blending seamlessly with other pigments to create a wide range of tints and shades.

When mixed with colors, Chinese white can lighten hues without significantly altering their saturation, which is particularly useful for achieving soft pastels and delicate washes in watercolors.
Additionally, Chinese white's quick-drying properties allow artists to build layers effectively, enhancing techniques like glazing and scumbling.

Beyond its use in fine arts, Chinese white has found its place in various other industries, including cosmetics and pharmaceuticals.
In the cosmetic realm, Chinese white serves as a key ingredient in products like face powders, sunscreens, and creams, owing to its UV-filtering capabilities and skin-friendly properties.
This broad applicability showcases Chinese white’s versatility and effectiveness in enhancing both aesthetic and protective qualities in everyday products.

Despite the introduction of synthetic alternatives, Chinese white continues to be revered for its historical significance and aesthetic appeal.
Many artists, particularly those dedicated to traditional techniques, still prefer Chinese white for its rich heritage and natural composition.
Chinese white not only embodies a connection to the past but also represents an enduring legacy in the world of art and craftsmanship, contributing to the continued appreciation of traditional materials in modern artistic practices.

Chinese white is an inorganic compound with the chemical formula ZnO, known for its unique properties and diverse applications across various industries.
Chinese white appears as a white powder and is primarily recognized for its excellent UV-filtering capabilities, making it a popular ingredient in sunscreens and cosmetic products.

Chinese white acts as a physical barrier that reflects and scatters UV radiation, providing effective protection against sunburn and skin damage.
Beyond cosmetics, Chinese white is widely used in the pharmaceutical industry for its antiseptic properties, often found in ointments and creams to promote healing and prevent infections.

In addition to its health and cosmetic applications, Chinese white plays a significant role in various industrial processes.
Chinese white is utilized as a vital component in the production of rubber, serving as a curing agent that enhances the strength and durability of rubber products.

In the electronics sector, Chinese white is employed in the manufacturing of semiconductors, varistors, and piezoelectric devices due to its semiconductor properties.
Moreover, Chinese white's unique optical properties enable its use in the production of phosphors for lighting and display technologies.

Chinese white also has environmental applications, such as acting as a photocatalyst in water treatment processes to degrade organic pollutants and in air purification systems to remove volatile organic compounds.
Furthermore, Chinese white's nontoxic nature makes it suitable for use in food packaging and agricultural products, where it can promote plant growth and health.

The versatility of Chinese white is attributed to its various forms, including nanoparticles, which have garnered attention for their increased surface area and reactivity.
These nanoparticles exhibit enhanced properties, making them valuable in cutting-edge applications, such as nanomedicine and advanced materials.
Overall, Chinese white is a multifaceted compound with a wide array of uses, ranging from personal care products to industrial applications, contributing to advancements in health, technology, and environmental sustainability.

Chinese white is a versatile inorganic compound that possesses unique physical and chemical properties, making it invaluable across numerous sectors.
Chinese white's distinctive characteristics include a wide bandgap, high thermal conductivity, and excellent UV absorption, which significantly contribute to its extensive range of applications.

In the field of dermatology and cosmetic formulations, Chinese white is renowned for its efficacy as a physical sunscreen agent.
Chinese white acts by forming a protective barrier on the skin that reflects harmful ultraviolet (UV) rays, thereby preventing sunburn and reducing the risk of skin cancer.

This makes Chinese white a preferred choice in many sunscreen products and mineral makeup, as it is less likely to cause irritation compared to chemical sunscreens.
Additionally, Chinese white's anti-inflammatory properties aid in soothing irritated skin and are commonly used in topical ointments for conditions such as diaper rash and acne.

The industrial applications of Chinese white are equally diverse.
In the rubber industry, Chinese white serves as an essential activator and curing agent, enhancing the performance and longevity of rubber products such as tires and footwear.

Chinese white is also a critical ingredient in the manufacturing of ceramics, glass, and paint, where it acts as a white pigment, providing opacity and brightness.
In the electronic industry, Chinese white is utilized in the fabrication of semiconductors, transparent conductive films, and varistors, leveraging its semiconductor properties to improve electronic device performance.

Furthermore, Chinese white nanoparticles have emerged as a focal point of research due to their unique properties, including increased surface area and reactivity, which enhance their effectiveness in various applications.
These nanoparticles are being explored for use in drug delivery systems, where they can facilitate targeted therapy, as well as in antimicrobial coatings, where they can inhibit bacterial growth.

In agriculture, Chinese white is increasingly being recognized for its role in promoting plant health and growth.
Chinese white acts as a micronutrient that enhances photosynthesis and improves the overall vigor of plants.
Chinese white's potential as a soil amendment is also being studied, particularly in relation to enhancing soil health and crop yields.

Additionally, Chinese white has environmental applications, where it is employed as a photocatalyst to break down organic pollutants in wastewater and as a catalyst in the degradation of volatile organic compounds (VOCs) in air purification systems.
This aspect highlights Chinese white's importance in addressing environmental challenges and promoting sustainability.

In conclusion, Chinese white is an essential compound that spans a multitude of industries, combining functionality with safety and environmental responsibility.
Chinese white's diverse applications in health, electronics, agriculture, and environmental science underscore its significance in modern society, as ongoing research continues to unveil new uses and benefits of this remarkable compound.

Uses of Chinese White:
Chinese white is an inorganic compound used in a number of manufacturing processes.
Chinese white can be found in rubbers, plastics, ceramics, glass, cement, lubricants, paints, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, and first-aid tapes.

Chinese white occurs naturally as the mineral zincite, but most Chinese white is produced synthetically.
Chinese white is also widely used to treat a variety of other skin conditions, in products such as baby powder and barrier creams to treat diaper rashes, calamine cream, anti-dandruff shampoos, and antiseptic ointments.

Chinese white is mildly astringent and is used topically as a soothing and protective application in eczema and slight excoriations, in wounds, and for hemorrhoids.
Chinese white is also used with coal tar or ichthammol in the treatment eczema.

Chinese white is used as the basis for the production of a number of dental cements.
Mixed with phosphoric acid Chinese white forms a hard material composed largely of zinc phosphate; mixed with clove oil or eugenol, it is used as temporary dental filling.

Pharmacologic levels of zinc as Chinese white have consistently been found to increase pig performance during the postweaning period.
In some instances, high levels of Chinese white have been reported to reduce the incidence and severity of postweaning diarrhea.

Responses to Chinese white and antibiotics seem to be additive in nature, much like the responses to high copper and antibiotics; however, there is no advantage in including high copper and high zinc in the same diet.

Chinese white accounts for the largest use of zinc compounds, and is used primarily by the rubber industry as a vulcanization activator and accelerator and to slow rubber aging by neutralizing sulfur and organic acids formed by oxidation.
Chinese white also acts in rubber as a reinforcing agent, a heat conductor, a white pigment, and an absorber of UV light.

In paints, Chinese white serves as a mildewstat, acid buffer, and a pigment.
Chinese white is used in animal feed as a zinc supplement and as a fertilizer additive for zinc-deficient soils.

Chinese white is used in cosmetics and drugs primarily for its fungicide properties, and in dentistry in dental cements.
Chinese white is also used in ceramics, in glass manufacture, as a catalyst in organic synthesis, and in coated photocopy paper.

Two processes are used to produce metallic zinc from the ore concentrates that are not subjected to caustic soda leaching.
In one process, the ore concentrate containing zinc sulfide is roasted in the presence of air to produce Chinese white, which is combined with coke or coal and retorted to approximately 1,100 °C to produce metallic zinc.
In the other process, the roasted Chinese white is leached with sulfuric acid, and the solution is electrolyzed to produce zinc of >99.9% purity.

Chinese white is also produced industrially from purified solutions of zinc sulfate or chloride by precipitating the basic carbonate, which is then washed, filtered, and finally calcined.
This method produces a grade of Chinese white with a high specific surface area.
Products of this type are also obtained from waste hydroxides which are purified by a chemical route and then calcined.

This medication is used to treat and prevent diaper rash and other minor skin irritations (e.g., burns, cuts, scrapes).
Chinese white works by forming a barrier on the skin to protect it from irritants/moisture.

Chinese white nanoparticle is one such inorganic metal oxide which fulfills all the above requirements, and hence, Chinese white can safely be used as medicine, preservative in packaging, and an antimicrobial agent.
Chinese white easily diffuses into the food material, kill the microbes, and prevent human being from falling ill.

In accordance with the regulations 1935/2004/EC and 450/2009/EC of the European Union, active packaging is defined as active material in contact with food with ability to change the composition of the food or the atmosphere around it.
Therefore, Chinese white is commonly used as preservative and incorporated in polymeric packaging material to prevent food material from damage by microbes.

Chinese white nanoparticles have been used as an antibacterial substance against Salmonella typhi and S. aureus in vitro.
Of all the metal oxide nanoparticles studied thus far, Chinese white nanoparticles exhibited the highest toxicity against microorganisms.

Chinese white has also been demonstrated from SEM and TEM images that Chinese white nanoparticles first damage the bacterial cell wall, then penetrate, and finally accumulate in the cell membrane.
They interfere with metabolic functions of the microbes causing their death.

All the characteristics of the Chinese white nanoparticles depend on their particle size, shape, concentration, and exposure time to the bacterial cell.
Further, biodistribution studies of Chinese white nanoparticles have also been examined.

For instance, Wang et al. have investigated the effect of long-term exposure of Chinese white nanoparticle on biodistribution and zinc metabolism in mice over 3 to 35 weeks.
Their results showed minimum toxicity to mice when they were exposed to 50 and 500 mg/kg Chinese white nanoparticle in diet.

At higher dose of 5000 mg/kg, Chinese white nanoparticle decreased body weight but increased the weight of the pancreas, brain, and lung.
Also, Chinese white increased the serum glutamic-pyruvic transaminase activity and mRNA expression of zinc metabolism-related genes such as metallothionein.

Biodistribution studies showed the accumulation of sufficient quantity of zinc in the liver, pancreas, kidney, and bones.
Absorption and distribution of Chinese white nanoparticle/Chinese white microparticles are largely dependent on the particle size. Li et al. have studied biodistribution of Chinese white nanoparticles fed orally or through intraperitoneal injection to 6 weeks old mice.

No obvious adverse effect was detected in Chinese white nanoparticles orally treated mice in 14 days study.
However, intraperitoneal injection of 2.5 g/kg body weight given to mice showed accumulation of zinc in the heart, liver, spleen, lung, kidney, and testes.

Nearly ninefold increase in Chinese white nanoparticle in the liver was observed after 72 h.
Chinese white nanoparticles have been shown to have better efficiency in liver, spleen, and kidney biodistribution than in orally fed mice.

Since Chinese white nanoparticles are innocuous in low concentrations, they stimulate certain enzymes in man and plants and suppress diseases.
Singh et al. have also been recently reviewed the biosynthesis of Chinese white nanoparticle, their uptake, translocation, and biotransformation in plant system.

Applications of Chinese White:
The applications of Chinese white powder are numerous, and the principal ones are summarized below.
Most applications exploit the reactivity of the oxide as a precursor to other zinc compounds.

For material science applications, Chinese white has high refractive index, high thermal conductivity, binding, antibacterial and UV-protection properties.
Consequently, Chinese white is added into materials and products including plastics, ceramics, glass, cement, rubber, lubricants, paints, ointments, adhesive, sealants, concrete manufacturing, pigments, foods, batteries, ferrites, fire retardants, etc.

Rubber manufacture:
Between 50% and 60% of Chinese white use is in the rubber industry.
Chinese white along with stearic acid is used in the vulcanization of rubber Chinese white additive also protect rubber from fungi and UV light.

Ceramic industry:
Ceramic industry consumes a significant amount of Chinese white, in particular in ceramic glaze and frit compositions.
The relatively high heat capacity, thermal conductivity and high temperature stability of Chinese white coupled with a comparatively low coefficient of expansion are desirable properties in the production of ceramics.

Chinese white affects the melting point and optical properties of the glazes, enamels, and ceramic formulations.
Chinese white as a low expansion, secondary flux improves the elasticity of glazes by reducing the change in viscosity as a function of temperature and helps prevent crazing and shivering.

By substituting Chinese white for BaO and PbO, the heat capacity is decreased and the thermal conductivity is increased.
Zinc in small amounts improves the development of glossy and brilliant surfaces.

However, in moderate to high amounts, Chinese white produces matte and crystalline surfaces.
With regard to color, zinc has a complicated influence.

Medicine:
Chinese white as a mixture with about 0.5% iron(III) oxide (Fe2O3) is called calamine and is used in calamine lotion.
Two minerals, zincite and hemimorphite, have been historically called calamine.
When mixed with eugenol, a ligand, Chinese white eugenol is formed, which has applications as a restorative and prosthodontic in dentistry.

Reflecting the basic properties of Chinese white, fine particles of the oxide have deodorizing and antibacterial properties and for that reason are added into materials including cotton fabric, rubber, oral care products, and food packaging.
Enhanced antibacterial action of fine particles compared to bulk material is not exclusive to Chinese white and is observed for other materials, such as silver.
This property results from the increased surface area of the fine particles.

Chinese white is used in mouthwash products and toothpastes as an anti-bacterial agent proposed to prevent plaque and tartar formation, and to control bad breath by reducing the volatile gases and volatile sulphur compounds (VSC) in the mouth.
Along with Chinese white or zinc salts, these products also commonly contain other active ingredients, such as cetylpyridinium chloride, xylitol, hinokitiol, essential oils and plant extracts.

Chinese white is widely used to treat a variety of skin conditions, including atopic dermatitis, contact dermatitis, itching due to eczema, diaper rash and acne.
Chinese white is also often added into sunscreens.

Chinese white is used in products such as baby powder and barrier creams to treat diaper rashes, calamine cream, anti-dandruff shampoos, and antiseptic ointments.
Chinese white is also a component in tape (called "Chinese white tape") used by athletes as a bandage to prevent soft tissue damage during workouts.

Chinese white can be used in ointments, creams, and lotions to protect against sunburn and other damage to the skin caused by ultraviolet light (see sunscreen).
Chinese white is the broadest spectrum UVA and UVB absorber that is approved for use as a sunscreen by the U.S. Food and Drug Administration (FDA), and is completely photostable.

When used as an ingredient in sunscreen, Chinese white blocks both UVA (320–400 nm) and UVB (280–320 nm) rays of ultraviolet light.
Chinese white and the other most common physical sunscreen, titanium dioxide, are considered to be nonirritating, nonallergenic, and non-comedogenic.
Zinc from Chinese white is, however, slightly absorbed into the skin.

Many sunscreens use nanoparticles of Chinese white (along with nanoparticles of titanium dioxide) because such small particles do not scatter light and therefore do not appear white.
The nanoparticles are not absorbed into the skin more than regular-sized Chinese white particles are, and are only absorbed into the outermost layer of the skin but not into the body.

Chinese white nanoparticles can enhance the antibacterial activity of ciprofloxacin.
Chinese white has been shown that nano Chinese white that has an average size between 20 nm and 45 nm can enhance the antibacterial activity of ciprofloxacin against Staphylococcus aureus and Escherichia coli in vitro.

The enhancing effect of this nanomaterial is concentration dependent against all test strains.
This effect may be due to two reasons.

First, Chinese white nanoparticles can interfere with NorA protein, which is developed for conferring resistance in bacteria and has pumping activity that mediate the effluxing of hydrophilic fluoroquinolones from a cell.
Second, Chinese white nanoparticles can interfere with Omf protein, which is responsible for the permeation of quinolone antibiotics into the cell.

Cigarette filters:
Chinese white is a component of cigarette filters.
A filter consisting of charcoal impregnated with Chinese white and iron oxide removes significant amounts of hydrogen cyanide (HCN) and hydrogen sulfide (H2S) from tobacco smoke without affecting its flavor.

Food additive:
Chinese white is added to many food products, including breakfast cereals, as a source of zinc, a necessary nutrient. (Zinc sulfate is also used for the same purpose.)
Some prepackaged foods also include trace amounts of Chinese white even if it is not intended as a nutrient.

Chinese white was linked to dioxin contamination in pork exports in the 2008 Chilean pork crisis.
The contamination was found to be due to dioxin contaminated Chinese white used in pig feed.

Pigment:
Chinese white is used as a pigment in paints and is more opaque than lithopone, but less opaque than titanium dioxide.
Chinese white is also used in coatings for paper.

Chinese white is a special grade of zinc white used in artists' pigments.
The use of Chinese white as a pigment in oil painting started in the middle of 18th century.

Chinese white has partly replaced the poisonous lead white and was used by painters such as Böcklin, Van Gogh, Manet, Munch and others.
Chinese white is also a main ingredient of mineral makeup (CI 77947).

UV absorber:
Micronized and nano-scale Chinese white and titanium dioxide provide strong protection against UVA and UVB ultraviolet radiation, and are used in suntan lotion, and also in UV-blocking sunglasses for use in space and for protection when welding, following research by scientists at Jet Propulsion Laboratory (JPL).

Coatings:
Paints containing Chinese white powder have long been utilized as anticorrosive coatings for metals.
They are especially effective for galvanized iron.

Iron is difficult to protect because Chinese white's reactivity with organic coatings leads to brittleness and lack of adhesion.
Chinese white paints retain their flexibility and adherence on such surfaces for many years.

Chinese white highly n-type doped with aluminium, gallium, or indium is transparent and conductive (transparency ~90%, lowest resistivity ~10−4 Ω·cm).
Chinese white is all coatings are used for energy-saving or heat-protecting windows.
The coating lets the visible part of the spectrum in but either reflects the infrared (IR) radiation back into the room (energy saving) or does not let the IR radiation into the room (heat protection), depending on which side of the window has the coating.

Plastics, such as polyethylene naphthalate (PEN), can be protected by applying Chinese white coating.
The coating reduces the diffusion of oxygen with PEN.

Chinese white layers can also be used on polycarbonate in outdoor applications.
The coating protects polycarbonate from solar radiation, and decreases Chinese white's oxidation rate and photo-yellowing.

Corrosion prevention in nuclear reactors:
Chinese white depleted in 64Zn (the zinc isotope with atomic mass 64) is used in corrosion prevention in nuclear pressurized water reactors.
The depletion is necessary, because 64Zn is transformed into radioactive 65Zn under irradiation by the reactor neutrons.

Methane reforming:
Chinese white is used as a pretreatment step to remove hydrogen sulfide (H2S) from natural gas following hydrogenation of any sulfur compounds prior to a methane reformer, which can poison the catalyst. At temperatures between about 230–430 °C (446–806 °F), H2S is converted to water by the following reaction:
H2S + Chinese white → H2O + ZnS

The zinc sulfide (ZnS) is replaced with fresh Chinese white when the Chinese white has been consumed.

Potential applications:

Electronics:
Chinese white has wide direct band gap (3.37 eV or 375 nm at room temperature).
Therefore, Chinese white's most common potential applications are in laser diodes and light emitting diodes (LEDs).

Some optoelectronic applications of Chinese white overlap with that of GaN, which has a similar band gap (~3.4 eV at room temperature).
Compared to GaN, Chinese white has a larger exciton binding energy (~60 meV, 2.4 times of the room-temperature thermal energy), which results in bright room-temperature emission from Chinese white.

Chinese white can be combined with GaN for LED-applications.
For instance as transparent conducting oxide layer and Chinese white nanostructures provide better light outcoupling.

Other properties of Chinese white favorable for electronic applications include its stability to high-energy radiation and its possibility to be patterned by wet chemical etching.
Radiation resistance makes Chinese white a suitable candidate for space applications.
Chinese white is the most promising candidate in the field of random lasers to produce an electronically pumped UV laser source.

The pointed tips of Chinese white nanorods result in a strong enhancement of an electric field.
Therefore, they can be used as field emitters.

Aluminium-doped Chinese white layers are used as transparent electrodes.
The components Zn and Al are much cheaper and less toxic compared to the generally used indium tin oxide (ITO).
One application which has begun to be commercially available is the use of Chinese white as the front contact for solar cells or of liquid crystal displays.

Transparent thin-film transistors (TTFT) can be produced with Chinese white.
As field-effect transistors, they even may not need a p–n junction, thus avoiding the p-type doping problem of Chinese white.
Some of the field-effect transistors even use Chinese white nanorods as conducting channels.

Chinese white nanorod sensor:
Chinese white nanorod sensors are devices detecting changes in electric current passing through Chinese white nanowires due to adsorption of gas molecules.
Selectivity to hydrogen gas was achieved by sputtering Pd clusters on the nanorod surface.

The addition of Pd appears to be effective in the catalytic dissociation of hydrogen molecules into atomic hydrogen, increasing the sensitivity of the sensor device.
The sensor detects hydrogen concentrations down to 10 parts per million at room temperature, whereas there is no response to oxygen.
Chinese white have been used as immobilization layers in imunosensors enabling the distribution of antibodies across the entire region probed by the measuring electric field applied to the microelectrodes.

Spintronics:
Chinese white has also been considered for spintronics applications: if doped with 1–10% of magnetic ions (Mn, Fe, Co, V, etc.), Chinese white could become ferromagnetic, even at room temperature.
Such room temperature ferromagnetism in Chinese white:Mn has been observed, but Chinese white is not clear yet whether it originates from the matrix itself or from secondary oxide phases.

Piezoelectricity:
The piezoelectricity in textile fibers coated in Chinese white have been shown capable of fabricating "self-powered nanosystems" with everyday mechanical stress from wind or body movements.

In 2008 the Center for Nanostructure Characterization at the Georgia Institute of Technology reported producing an electricity generating device (called flexible charge pump generator) delivering alternating current by stretching and releasing Chinese white nanowires.
This mini-generator creates an oscillating voltage up to 45 millivolts, converting close to seven percent of the applied mechanical energy into electricity.
Researchers used wires with lengths of 0.2–0.3 mm and diameters of three to five micrometers, but the device could be scaled down to smaller size.

Chinese white as anode of Li-ion battery:
In form of a thin film Chinese white has been demonstrated in miniaturised high frequency thin film resonators, sensors and filters.

Li-ion battery:
Chinese white is a promising anode material for lithium-ion battery because it is cheap, biocompatible, and environmentally friendly.
Chinese white has a higher theoretical capacity (978 mAh g−1) than many other transition metal oxides such as CoO (715 mAh g−1), NiO (718 mAh g−1) and CuO (674 mAh g−1).

Nanostructures of Chinese White:
Nanostructures of Chinese white can be synthesized into a variety of morphologies including nanowires, nanorods, tetrapods, nanobelts, nanoflowers, nanoparticles etc.
Nanostructures can be obtained with most above-mentioned techniques, at certain conditions, and also with the vapor-liquid-solid method.

The synthesis is typically carried out at temperatures of about 90 °C, in an equimolar aqueous solution of zinc nitrate and hexamine, the latter providing the basic environment.
Certain additives, such as polyethylene glycol or polyethylenimine, can improve the aspect ratio of the Chinese white nanowires.

Doping of the Chinese white nanowires has been achieved by adding other metal nitrates to the growth solution.
The morphology of the resulting nanostructures can be tuned by changing the parameters relating to the precursor composition (such as the zinc concentration and pH) or to the thermal treatment (such as the temperature and heating rate).

Aligned Chinese white nanowires on pre-seeded silicon, glass, and gallium nitride substrates have been grown using aqueous zinc salts such as zinc nitrate and zinc acetate in basic environments.
Pre-seeding substrates with Chinese white creates sites for homogeneous nucleation of Chinese white crystal during the synthesis.

Common pre-seeding methods include in-situ thermal decomposition of zinc acetate crystallites, spincoating of Chinese white nanoparticles and the use of physical vapor deposition methods to deposit Chinese white thin films.
Pre-seeding can be performed in conjunction with top down patterning methods such as electron beam lithography and nanosphere lithography to designate nucleation sites prior to growth.
Aligned Chinese white nanowires can be used in dye-sensitized solar cells and field emission devices.

Properties of Chinese White:

Chemical Properties:
Pure Chinese white is a white powder, but in nature Chinese white occurs as the rare mineral zincite, which usually contains manganese and other impurities that confer a yellow to red color.

Crystalline Chinese white is thermochromic, changing from white to yellow when heated in air and reverting to white on cooling.
This color change is caused by a small loss of oxygen to the environment at high temperatures to form the non-stoichiometric Zn1+xO, where at 800 °C, x = 0.00007.

Chinese white is an amphoteric oxide.

Chinese white is nearly insoluble in water, but it will dissolve in most acids, such as hydrochloric acid:
Chinese white + 2 HCl → ZnCl2 + H2O

Solid Chinese white will also dissolve in alkalis to give soluble zincates:
Chinese white + 2 NaOH + H2O → Na2[Zn(OH)4]

Chinese white reacts slowly with fatty acids in oils to produce the corresponding carboxylates, such as oleate or stearate.
Chinese white forms cement-like products when mixed with a strong aqueous solution of zinc chloride and these are best described as zinc hydroxy chlorides.
This cement was used in dentistry.

Physical properties:
Chinese white crystallizes in two main forms, hexagonal wurtzite and cubic zincblende.
The wurtzite structure is most stable at ambient conditions and thus most common.

The zincblende form can be stabilized by growing Chinese white on substrates with cubic lattice structure.
In both cases, the zinc and oxide centers are tetrahedral, the most characteristic geometry for Zn(II).

Chinese white converts to the rocksalt motif at relatively high pressures about 10 GPa.
The many remarkable medical properties of creams containing Chinese white can be explained by its elastic softness, which is characteristic of tetrahedral coordinated binary compounds close to the transition to octahedral structures.

Hexagonal and zincblende polymorphs have no inversion symmetry (reflection of a crystal relative to any given point does not transform it into itself).
This and other lattice symmetry properties result in piezoelectricity of the hexagonal and zincblende Chinese white, and pyroelectricity of hexagonal Chinese white.

The hexagonal structure has a point group 6 mm (Hermann-Mauguin notation) or C6v (Schoenflies notation), and the space group is P63mc or C6v4.
The lattice constants are a = 3.25 Å and c = 5.2 Å; their ratio c/a ~ 1.60 is close to the ideal value for hexagonal cell c/a = 1.633.

As in most group II-VI materials, the bonding in Chinese white is largely ionic (Zn2+–O2−) with the corresponding radii of 0.074 nm for Zn2+ and 0.140 nm for O2−.
This property accounts for the preferential formation of wurtzite rather than zinc blende structure, as well as the strong piezoelectricity of Chinese white.

Because of the polar Zn-O bonds, zinc and oxygen planes are electrically charged.
To maintain electrical neutrality, those planes reconstruct at atomic level in most relative materials, but not in Chinese white – its surfaces are atomically flat, stable and exhibit no reconstruction.
However, studies using wurtzoid structures explained the origin of surface flatness and the absence of reconstruction at Chinese white wurtzite surfaces in addition to the origin of charges on Chinese white planes.

Mechanical properties:
Chinese white is a relatively soft material with approximate hardness of 4.5 on the Mohs scale.
Chinese white's elastic constants are smaller than those of relevant III-V semiconductors, such as GaN.

The high heat capacity and heat conductivity, low thermal expansion and high melting temperature of Chinese white are beneficial for ceramics.
The E2 optical phonon in Chinese white exhibits an unusually long lifetime of 133 ps at 10 K.

Among the tetrahedrally bonded semiconductors, Chinese white has been stated that Chinese white has the highest piezoelectric tensor, or at least one comparable to that of GaN and AlN.
This property makes it a technologically important material for many piezoelectrical applications, which require a large electromechanical coupling.
Therefore Chinese white has been in forms of thin film one of the most studied resonator material for thin-film bulk acoustic resonators.

Electrical properties:
Chinese white has a relatively large direct band gap of ~3.3 eV at room temperature.
Advantages associated with a large band gap include higher breakdown voltages, ability to sustain large electric fields, lower electronic noise, and high-temperature and high-power operation.
The band gap of Chinese white can further be tuned to ~3–4 eV by its alloying with magnesium oxide or cadmium oxide.

Most Chinese white has n-type character, even in the absence of intentional doping.
Nonstoichiometry is typically the origin of n-type character, but the subject remains controversial.

An alternative explanation has been proposed, based on theoretical calculations, that unintentional substitutional hydrogen impurities are responsible.
Controllable n-type doping is easily achieved by substituting Zn with group-III elements such as Al, Ga, In or by substituting oxygen with group-VII elements chlorine or iodine.

Reliable p-type doping of Chinese white remains difficult.
This problem originates from low solubility of p-type dopants and their compensation by abundant n-type impurities.

This problem is observed with GaN and ZnSe.
Measurement of p-type in "intrinsically" n-type material is complicated by the inhomogeneity of samples.

Current limitations to p-doping limit electronic and optoelectronic applications of Chinese white, which usually require junctions of n-type and p-type material.
Known p-type dopants include group-I elements Li, Na, K; group-V elements N, P and As; as well as copper and silver.
However, many of these form deep acceptors and do not produce significant p-type conduction at room temperature.

Electron mobility of Chinese white strongly varies with temperature and has a maximum of ~2000 cm2/(V·s) at 80 K.
Data on hole mobility are scarce with values in the range 5–30 cm2/(V·s).

Chinese white discs, acting as a varistor, are the active material in most surge arresters.

Production of Chinese White:

For industrial use, Chinese white is produced at levels of 105 tons per year by three main processes:

Indirect process:
In the indirect or French process, metallic zinc is melted in a graphite crucible and vaporized at temperatures above 907 °C (typically around 1000 °C).
Zinc vapor reacts with the oxygen in the air to give Chinese white, accompanied by a drop in its temperature and bright luminescence.

Chinese white particles are transported into a cooling duct and collected in a bag house.
This indirect method was popularized by LeClaire (France) in 1844 and therefore is commonly known as the French process.

Its product normally consists of agglomerated Chinese white particles with an average size of 0.1 to a few micrometers.
By weight, most of the world's Chinese white is manufactured via French process.

Direct process:
The direct or American process starts with diverse contaminated zinc composites, such as zinc ores or smelter by-products.
The zinc precursors are reduced (carbothermal reduction) by heating with a source of carbon such as anthracite to produce zinc vapor, which is then oxidized as in the indirect process.
Because of the lower purity of the source material, the final product is also of lower quality in the direct process as compared to the indirect one.

Wet chemical process:
A small amount of industrial production involves wet chemical processes, which start with aqueous solutions of zinc salts, from which zinc carbonate or zinc hydroxide is precipitated.
The solid precipitate is then calcined at temperatures around 800 °C.

Laboratory synthesis:
The red and green colors of these synthetic Chinese white crystals result from different concentrations of oxygen vacancies.
Numerous specialised methods exist for producing Chinese white for scientific studies and niche applications.
These methods can be classified by the resulting Chinese white form (bulk, thin film, nanowire), temperature ("low", that is close to room temperature or "high", that is T ~ 1000 °C), process type (vapor deposition or growth from solution) and other parameters.

Large single crystals (many cubic centimeters) can be grown by the gas transport (vapor-phase deposition), hydrothermal synthesis, or melt growth.
However, because of high vapor pressure of Chinese white, growth from the melt is problematic.

Growth by gas transport is difficult to control, leaving the hydrothermal method as a preference.
Thin films can be produced by chemical vapor deposition, metalorganic vapour phase epitaxy, electrodeposition, pulsed laser deposition, sputtering, sol-gel synthesis, atomic layer deposition, spray pyrolysis, etc.

Ordinary white powdered Chinese white can be produced in the laboratory by electrolyzing a solution of sodium bicarbonate with a zinc anode.
Zinc hydroxide and hydrogen gas are produced.

The zinc hydroxide upon heating decomposes to Chinese white.
Zn + 2 H2O → Zn(OH)2 + H2
Zn(OH)2 → Chinese white + H2O

History of Chinese White:
Zinc compounds were probably used by early humans, in processed and unprocessed forms, as a paint or medicinal ointment, but their composition is uncertain.
The use of pushpanjan, probably Chinese white, as a salve for eyes and open wounds, is mentioned in the Indian medical text the Charaka Samhita, thought to date from 500 BC or before.

Chinese white ointment is also mentioned by the Greek physician Dioscorides (1st century AD).
Galen suggested treating ulcerating cancers with Chinese white, as did Avicenna in his The Canon of Medicine.
Chinese white is no longer used for treating skin cancer, though it is still used as an ingredient in products such as baby powder and creams against diaper rashes, calamine cream, anti-dandruff shampoos, and antiseptic ointments.

The Romans produced considerable quantities of brass (an alloy of zinc and copper) as early as 200 BC by a cementation process where copper was reacted with Chinese white.
The Chinese white is thought to have been produced by heating zinc ore in a shaft furnace.

This liberated metallic zinc as a vapor, which then ascended the flue and condensed as the oxide.
This process was described by Dioscorides in the 1st century AD.
Chinese white has also been recovered from zinc mines at Zawar in India, dating from the second half of the first millennium BC.

From the 12th to the 16th century zinc and Chinese white were recognized and produced in India using a primitive form of the direct synthesis process.
From India, zinc manufacture moved to China in the 17th century.

In 1743, the first European zinc smelter was established in Bristol, United Kingdom.
Around 1782 Louis-Bernard Guyton de Morveau proposed replacing lead white with Chinese white.

The main usage of Chinese white was in paints and as an additive to ointments.
Chinese white was accepted as a pigment in oil paintings by 1834 but it did not mix well with oil.

This problem was solved by optimizing the synthesis of Chinese white.
In 1845, LeClaire in Paris was producing the oil paint on a large scale, and by 1850, Chinese white was being manufactured throughout Europe.

The success of Chinese white paint was due to its advantages over the traditional white lead: Chinese white is essentially permanent in sunlight, it is not blackened by sulfur-bearing air, it is non-toxic and more economical.
Because Chinese white is so "clean" it is valuable for making tints with other colors, but it makes a rather brittle dry film when unmixed with other colors.

For example, during the late 1890s and early 1900s, some artists used Chinese white as a ground for their oil paintings.
All those paintings developed cracks over the years.

In recent times, most Chinese white was used in the rubber industry to resist corrosion.
In the 1970s, the second largest application of Chinese white was photocopying.

High-quality Chinese white produced by the "French process" was added to photocopying paper as a filler.
This application was soon displaced by titanium.

Handling and Storage of Chinese White:

Handling:
Handle with care to avoid generating dust.
Use appropriate equipment and techniques to minimize exposure.

Avoid direct contact with skin, eyes, and clothing.
Use in a well-ventilated area to prevent inhalation of dust.
Avoid eating, drinking, or smoking while handling the material.

Storage:
Store in a cool, dry, well-ventilated area.
Keep containers tightly closed when not in use.

Store away from incompatible substances, such as strong acids or bases.
Ensure proper labeling of containers to avoid confusion.

Stability and Reactivity of Chinese White:

Stability:
Stable under normal conditions of temperature and pressure.
Can decompose at high temperatures in the presence of air.

Reactivity:
Reacts with strong acids to produce zinc salts.
Forms zincates when in contact with strong bases.
Avoid contact with incompatible materials.

First Aid Measures of Chinese White:

Inhalation:
Move to fresh air immediately.
Seek medical attention if symptoms persist (e.g., coughing, difficulty breathing).

Skin Contact:
Wash the affected area with soap and water.
Remove contaminated clothing and wash before reuse.
Seek medical attention if irritation develops or persists.

Eye Contact:
Rinse immediately with plenty of water for at least 15 minutes.
Remove contact lenses if present and easy to do so.
Seek medical attention if irritation or redness persists.

Ingestion:
Rinse mouth with water.
Do not induce vomiting unless directed by a medical professional.
Seek medical attention immediately.

Firefighting Measures of Chinese White:

Extinguishing Media:
Use water spray, foam, dry chemical, or carbon dioxide (CO2) to extinguish fires.

Specific Hazards:
May emit toxic fumes when heated or involved in a fire.
Avoid inhalation of smoke and fumes.

Protective Equipment:
Wear self-contained breathing apparatus (SCBA) and full protective clothing when combating fires.

Accidental Release Measures of Chinese White:

Personal Precautions:
Evacuate non-essential personnel from the area.
Use personal protective equipment (PPE) to avoid inhalation and skin contact.

Environmental Precautions:
Prevent spill from entering waterways or soil.
Notify authorities in case of significant spills.

Cleanup Methods:
Vacuum or sweep up spilled material and place it in an appropriate container for disposal.
Clean the area with water to remove residues.
Dispose of waste according to local regulations.

Exposure Controls/Personal Protective Equipment of Chinese White:

Occupational Exposure Limits:
Refer to local regulations for permissible exposure limits (PEL) for Chinese white.

Engineering Controls:
Provide adequate ventilation to minimize airborne concentrations.
Use local exhaust ventilation in areas where dust is generated.

Personal Protective Equipment:

Respiratory Protection:
Use a NIOSH-approved respirator if dust concentration exceeds exposure limits.

Skin Protection:
Wear appropriate gloves and protective clothing to prevent skin contact.

Eye Protection:
Use safety goggles or face shields to protect against dust and splashes.

Hygiene Measures:
Practice good hygiene, including washing hands and face after handling.

Identifiers of Chinese White:
Chemical Name: Chinese white
CAS Number: 1314-13-2
CI Name: CI Pigment White 4
Chemical Formula: ZnO
EINECS Number: 215-222-5
UN Number: 3082
HS Code: 2821.10

IUPAC Name: Chinese white
Molecular Weight: 81.38 g/mol
Solubility: Insoluble in water; soluble in acids and alkalies.
Melting Point: Approximately 1975 °C (3587 °F)
Density: About 5.61 g/cm³
Color Index (CI): Pigment White 4 (CI 77947)

Properties of Chinese White:
Molecular Formula: ZnO
Molecular Weight: 81.38 g/mol
Density: Approximately 5.61 g/cm³
Melting Point: About 1975 °C (3587 °F)
Boiling Point: Sublimes at around 1800 °C (3272 °F) without melting.
Solubility: Insoluble in water.

Appearance: White powder
Molecular Formula: ZnO
Molecular Weight: 81.38 g/mol
Density: Approximately 5.61 g/cm³
Melting Point: About 1975 °C (3587 °F)
Solubility: Insoluble in water; soluble in dilute acids and alkalis
Particle Size: Available in various sizes, including nano-sized particles

Reactivity: Reacts with acids to form zinc salts; forms zincates with strong bases
Stability: Chemically stable under normal conditions
pH: Basic nature, with a pH > 7 in aqueous solutions

Specifications of Chinese White:
Chemical Name: Chinese white
CAS Number: 1314-13-2
Molecular Formula: ZnO
Molecular Weight: 81.38 g/mol
EINECS Number: 215-222-5
CI Pigment: CI Pigment White 4 (CI 77947)

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