Zinc oxide powder is a white or yellowish powder commonly used for manufacturing everything from cosmetics and personal care products to plastics and rubber. Manufacturers create the powder from both zinc and zinc ore but can also produce the substance synthetically in a lab. Centuries ago zinc oxide ointments were used for medicinal purposes. Around 500 BC Indian physicians believed that zinc oxide products possessed healing properties, and Greek physicians used zinc oxide powder in skin ointments in the first century.
The French method of creating zinc oxide powder requires melting zinc at extreme temperatures of around 1,832 degrees Fahrenheit (1,000 degrees Celsius). During the melting process, metal particles vaporize, combining with oxygen to form zinc oxide. A collection chamber traps the new compound and cools the particles, which form a white to yellow colored powder with the consistency of baking flour. Microscopically, the particles appear crystal-like, with cubed or hexagonal shapes.
The American process of manufacturing zinc oxide powder requires heating zinc ores and anthracite until vaporization occurs. Vapors combine with oxygen and cool, forming the powder. Laboratories synthesize zinc oxide powder using a process known as hydrolysis. Electric current runs through a zinc anode immersed in a sodium bicarbonate solution, producing zinc hydroxide and hydrogen gas. The zinc hydroxide decomposes and forms zinc oxide.
Many consumer products contain zinc oxide powder. Companies manufacture adhesives, plastics and rubber products, using zinc oxide as one of the ingredients. The substance initiates the curing process and reinforces chemical bonds, increasing overall strength. The compound resists moisture and protects products from heat damage as well. The resilience of the chemical compound aids in maintaining the shelf life of many products.
Common items that contain zinc oxide include insulation, outdoor public seating, recreational equipment, and tires. Dental inlays and the white pigment in paints, paper, and other products are often produced by zinc oxide powder. The substance resists fading and maintains a bright white color by reflecting light. The ability to scatter ultraviolet rays also proves useful as a sun blocking agent.
Zinc oxide powder is also resists bacterial and fungal growth and is often found in deodorants. Parents often use zinc oxide ointment as a preventative or to assist in the healing of diaper rash. The moisture resistant compound protects skin from external moisture and irritants. Many skin and hair care products, along with cosmetics, contain zinc oxide. The chemical compound acts as an emollient and prevents moisture loss from skin and hair.