99% Zinc phosphate CAS 7779-90-0

1. What is Zinc phosphate?

Zinc phosphate also called zinc phosphate or zinc white phosphate is the orthophosphate of zinc. It is one of the inorganic phosphate compounds and its chemical formula is usually written as:

Zn3(PO4)2 (CAS No.: 7779-90-0, molecular weight of anhydrous form about 386.11; industrial grade is usually the dihydrate Zn3(PO4)2·2H2O, molecular weight about 422.08, theoretical zinc content 46.46%

It is a colorless orthorhombic crystal or white microcrystalline powder at room temperature. It is non-toxic, odorless, has a density of about 3.998 g/cm3 and a melting point of about 900℃. It is hardly soluble in water soluble in inorganic acid ammonia and ammonium salt solutions insoluble in ethanol. The natural mineral of zinc phosphate is called paraphosphite and it occurs in two crystal forms α-type and β-type.

Zinc phosphate – Zinc phosphate is made of zinc ions (Zn2+) and phosphate ions (PO4³-). In anti-rust coatings, it hydrolyzes slowly to release phosphate ions, which react with the steel substrate to form an insoluble iron phosphate passivation film. Simultaneously, the zinc ions create a protective complex. Thus, electrochemical corrosion inhibition occurs through a dual mechanism. Zinc ions also are of particular importance in dental and agricultural applications.This functional basis of the “slow release film-forming + zinc activity” combination is also the basis for the wide application of zinc ions in anti-corrosion coatings, dental materials and zinc fertilizers.

Zinc phosphate is chemically stable and non-toxic. It is practically insoluble in water and ethanol but soluble in inorganic acids, ammonia and ammonium salt solution. It is the most important and widely used phosphate rust-preventive pigment, and can be used to replace traditional rust-preventive pigments containing lead and chromium. Keep in a dry, closed container.

Non-industrial grade zinc phosphate is used in research and consumer applications and is primarily specified as dental and reagent grade. Compared with industrial grade, non-industrial grade products pay more attention to the following indicators:

Purity and Impurity Control

Dental zinc phosphate must be strictly controlled for impurities and heavy metals.

Heavy metal limits (lead, arsenic, etc.)

Products used in dentistry have strict limits on harmful impurities such as heavy metals, which are important safety indicators.

granularity

Fineness affects the performance of dental mixing and the uniformity of scientific research experiments; therefore, particle size must be controlled according to the intended use.

Moisture

Moisture content affects measurement accuracy and mixing performance, and must be kept at a low level.

II. What are the uses of Zinc phosphate?

1. Dental Applications (Core Applications)

Zinc phosphate cement is a classic cementing material used in the dental field for decades. It is made by mixing zinc phosphate powder with phosphoric acid solution and is used to cement crowns, inlays, bridges, as well as linings and fillings. It is characterized by high strength and good biocompatibility.

2. Rust-preventing pigments (core application)

Zinc phosphate is the most important and widely used phosphate anti-corrosion pigment. It forms a passivation film on the steel surface through a dual mechanism of slow-release phosphate and zinc ions, inhibiting electrochemical corrosion. It is widely used in oil-based and water-based anti-corrosion primers and topcoats, and is applied to heavy-duty anti-corrosion coatings for bridges, automobiles, ships, containers and steel structures. It can replace traditional lead-chromium anti-corrosion pigments.

3. Reagent grade for scientific research and laboratory use

Zinc phosphate is an important material in the research of anti-corrosion coatings, metal rust prevention and phosphating mechanisms. It can also be used as a reference material for determination of zinc content and analysis chemical reagent. It is a common laboratory reagent for materials and chemistry.

4. Agriculture and Horticulture (Agricultural Grade)

Zinc phosphate can be used as trace element zinc fertilizer to supplement crops with zinc and improve crop nutrition in zinc deficient soils and used in agricultural and horticultural production.

5. Base material for coating

It is used as a base material and pigment component in phenolic, epoxy and alkyd coatings. It is compatible well with resin systems, and may improve the adhesion and anti-corrosion properties of coatings. It is used in industrial anti-corrosion coating, and powder coating.

6. Metal phosphating treatment

Zinc phosphate is an important component of metal phosphating solutions. It is used for phosphating treatment of metal surfaces such as steel to form a dense zinc phosphate phosphating film, which improves coating adhesion and corrosion resistance. It is widely used in the pretreatment of coatings for automobiles, home appliances, and hardware parts.

7. Flame retardants

Zinc phosphate can be used as a flame retardant for chlorinated rubber and organic polymer materials. It works synergistically with halogenated flame retardant systems and is applied in flame retardant coatings, flame retardant plastics and flame retardant rubber products.

8. Glass and ceramic additives

Zinc phosphate can be used as an additive for glass and ceramics to help improve the properties of glass melting and ceramic glazes, and is applied in the production of specialty glass and ceramic products.

9. Artwork and DIY Rust Prevention (Consumer Grade)

Zinc phosphate anti-rust primer can be used for self-rust prevention coating of metal products, helping enthusiasts deal with the problem of rust on metal parts. It is a commonly used anti-rust coating for home DIY and craft making.

10. Other Applications

With the development of anti-corrosion technology and biomaterials research, the application scope of non-industrial grade zinc phosphate continues to expand, including teaching experiments, custom synthesis, and standard reagent supply.

Summarize

Zinc phosphate, also known as zinc phosphate (zinc phosphate white), is a white crystalline powder of inorganic phosphate. It is non-toxic, almost insoluble in water, and is the most important non-toxic anti-rust pigment to replace lead- and chromium-containing pigments. It is also a core component of zinc phosphate cement, a classic dental cementing material. In daily life, we indirectly come into contact with it through metal anti-rust coatings, dental materials, phosphated metal parts, zinc fertilizers, and flame-retardant products. In non-industrial applications, zinc phosphate is widely used in dental cementation and restoration , anti-corrosion and phosphating mechanism research, trace element zinc fertilizers, and rust prevention in art, making it an important phosphate compound connecting "daily use" with "health, scientific research, and agriculture."