In 1743, the first European zinc smelter was established in Bristol, United Kingdom. From India, zinc manufacture moved to China in the 17th century. įrom the 12th to the 16th century zinc and zinc oxide were recognized and produced in India using a primitive form of the direct synthesis process. Zinc oxide has also been recovered from zinc mines at Zawar in India, dating from the second half of the first millennium BC. This process was described by Dioscorides in the 1st century AD. This liberated metallic zinc as a vapor, which then ascended the flue and condensed as the oxide. The zinc oxide is thought to have been produced by heating zinc ore in a shaft furnace. 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 zinc oxide. It is used as an ingredient in products such as baby powder and creams against diaper rashes, calamine cream, anti- dandruff shampoos, and antiseptic ointments. Galen suggested treating ulcerating cancers with zinc oxide, as did Avicenna in his The Canon of Medicine. Zinc oxide ointment is also mentioned by the Greek physician Dioscorides (1st century AD). The use of pushpanjan, probably zinc oxide, 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. Zinc compounds were probably used by early humans, in processed and unprocessed forms, as a paint or medicinal ointment, but their composition is uncertain. Although it occurs naturally as the mineral zincite, most zinc oxide is produced synthetically.
ZnO is used as an additive in numerous materials and products including cosmetics, food supplements, rubbers, plastics, ceramics, glass, cement, lubricants, paints, sunscreens, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, semi conductors, and first-aid tapes. It is a white powder that is insoluble in water. Zinc oxide is an inorganic compound with the formula Zn O.
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