Grade 500WSA

High Purity French Process Zinc Oxide

Grade 500WSA is a brilliant white powder manufactured by the French (Indirect) Process.

Grade 500WSA is a popular general use high quality zinc oxide.

Grade 500WSA is approved for pharmaceutical drug use as an excipient, is USFDA approved as GRAS (Generally Recognized As Safe) at 21cfr182.8991 and is authorized by the USFDA for use wherever GRAS is approved including food contact in rubber, plastics, and coatings.

Grade 500WSA also meets the requirements of ASTM specification D79, 2002/95/EC Restriction of Hazardous Substances Directive (RoHS) for heavy metals and Waste Electrical and Electronic Directive (WEEE}, and other regulations where high quality zinc oxide is required.

Grade 500WSA replaces grade ZOCO 600

Key Features

Zinc oxide provides a variety of benefits and functionalities depending on the end use.

Rubber Applications:  Zinc oxide is used as an activator in the vulcanization or curing process. It increases the effect of organic accelerators in rubber vulcanization.  Zinc oxide adds strength to rubber compounds, improves their resistance to heat and abrasion and helps guard against ultraviolet degradation.

  • Tires
  • Latex compounds
  • Food & Pharmaceutical Grade rubber applications
  • Truck and Passenger Car Tires
  • Hoses
  • Belts
  • Gaskets
  • Door channel, window channel
  • Shoe soles and heels; boots
  • Wire and cable rubber jackets and insulation
  • Inflatable boats
  • Carpet backing
  • Custom rubber compounds


Coatings & Inks Applications:  A key benefit for various types of coatings is protection from otherwise harmful UV radiation.

  • Coatings formulated with zinc oxide exhibit improved biocidal functions, improved color retention and improved durability under varying climatic conditions.
  • Zinc oxide reduces the effect of yellowing when formulated in interior enamels.
  • High surface zinc oxide can also be used as a can lacquer coating to present the effects of food discoloration from sulfides of iron or tin.
  • Affords good corrosive inhibiting properties and improves water resistance
  • Zinc oxide also neutralizes harmful acids


Adhesives & Tape Applications:  Many tapes and their adhesives are rubber-based which use zinc oxide as an additive.  Zinc Oxide adds strength to rubber tapes and adhesives and improves their resistance to heat and abrasion.  It helps guard against degradation from sunlight or other sources of ultraviolet light.  Zinc oxide can be used as a catalyst or cross-linker in certain adhesive formulas.

  • Industrial Tapes
  • Surgical & First Aid Tapes
  • Rubber Based Adhesives

Plastics Applications:  Mixed metal stabilizers for plastics are an important and growing use for zinc oxide. While Ba/Zn and Ca/Zn liquid stabilizers have been the most popular stabilizers for PVC plastisols, environmentally friendly Ba/Zn systems are now replacing cadmium containing stabilizers.  The opacity of zinc oxide to ultraviolet radiation makes it a useful pigment to protect outdoor plastic compounds from UV degradation.

  • Polyolefins – acid scavenging in LLDPE, HDPE, and PP
  • PVC stabilizers – heat stability
  • Thin films – UV light protection
  • Catalysts – various uses in plastics compounds
  • TPE’s – curing and crosslinking


Oil Additives and Lubricants Applications:  Zinc oxide can be used as an additive to oil and petroleum based lubricants.  It is used as a heat stabilizer for greases and improves wear resistance in solid lubricants.

  • Manufacture ZDDP (dialkydithio-phosphate) - Anti corrosion, and anti-wear additive used in virtually all lubricants
  • Mold release lubricant
  • White greases


Agricultural Applications:  Zinc oxide is widely used to supply zinc as a trace element for crops in fertilizers and sprays and for animal nutrition in prepared feeds.

Miscellaneous Applications:

  • Ceramic Tiles & Frit Enamels
  • Glass - Stained glass, glass fibers, drinking glasses
  • Metal Oxide Surge Arrestors (Varistors) & Magnetic Ferrites


Chemical Intermediate Applications:  Zinc oxide is used in the production of hundreds of different zinc-based chemicals as a reaction intermediate.  Examples in various industries include:


  • Zinc sulfate – encourages plant growth
  • Zinc nitrate – corrects zinc deficiencies
  • Zinc EDTA – chelating agent


  • Zinc borate – smoke suppressant, flame retardant
  • Zinc octoate and neodecanoate – paint driers, PVC stabilizers
  • Zinc phosphate – corrosion resistance


  • ZMBT, ZDMC, ZDEC, ZDBC – accelerators
  • Zinc stearate – mold release agents
  • Zinc diacrylate – golf ball centers


  • Zinc bromide – oil well drilling fluids
  • Zinc citrate – dental care, human nutrition
  • Zinc chloride – batteries, metallurgical fluxes
  • Zinc gluconate – zinc lozenges
  • Zinc resinate – printing inks

Recommended Applications

This grade is used where lower impurities and high assay are required, and where a wider m2/g surface area is suitable. Typical applications include:

  • Fertilizer
  • Feed
  • Ceramics
  • Rubber
  • Plastics
  • Coatings