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Zinc phosphate
Zinc phosphate
Identifiers
CAS number 7779-90-0
Properties
Molecular formula Zn3(PO4)2
Molar mass 386.11 g/mol
Appearance white crystals
Density 4 g/cm3, solid
Melting point

900°C

Solubility in water Insoluble
Structure
Crystal structure monoclinic
Hazards
EU classification not listed
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox references

Zinc phosphate (Zn3(PO4)2) is an inorganic chemical compound used as a corrosion resistant coating on metal surfaces either as part of an electroplating process or applied as a primer pigment (see also red lead). Zinc phosphate coats better on a crystalline structure than bare metal, so a seeding agent is often used as a pre-treatment. One common agent is sodium pyrophosphate[1]

Zinc phosphate is formed from zinc phosphate cement and used in dentistry. Zinc phosphate cement is one of the oldest and widely used cements, and is commonly used for luting permanent metal restorations and as a base for dental restorations. Zinc phosphate cement is used for cementation of inlays, crowns, bridges, and orthodontic appliances and occasionally as a temporary restoration. It is prepared by mixing zinc oxide and magnesium oxide powders with a liquid consisting principally of phosphoric acid, water, and buffers. It is the standard cement to measure against. It has the longest track record of use in dentistry. It is still commonly used, however, resin-modified glass ionomer cements are more convenient and stronger when used in a dental setting.


References[]

  1. Menke, Joseph T.. Zinc Phosphate Coatings on NonFerrous Substrates -- Part I. PFOnline. Retrieved on 2006-08-07.


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