Zinc phosphate – a professional-grade raw material for industry and laboratories

Zinc phosphate (Zn₃(PO₄)₂) – high purity, competitive price, 24-hour delivery. We are an experienced distributor of chemical raw materials, offering zinc phosphate in various grades: technical, pure, analytical grade (p.a.), and in specialty grades for paints, anti-corrosion coatings, and plastics.

Our product is designed for paint and varnish manufacturers, the protective coatings industry, plastics manufacturers, the construction chemicals sector, the electroplating industry, and research laboratories. We include a certificate of analysis (CoA), a safety data sheet (SDS), and complete technical documentation with every shipment. We guarantee consistent quality across batches, competitive wholesale prices, and technical support.

Basic Specifications – Zinc Phosphate Zn₃(PO₄)₂

Zinc phosphate – price and pricing factors

The price of the product depends on several key factors:

• Chemical purity: pharmaceutical-grade (p.a.) products are more expensive than technical-grade ones
• Industry-specific specifications: Grades for anti-corrosion paints (with controlled particle size and specific surface area) are more expensive than standard grades
• Order size: the price per kg decreases with larger quantities (volume discounts)
• Particle size and surface treatment: Surface-modified products command a higher price
• Packaging: standard bags vs. big bags vs. specialized packaging
• Documentation: Additional certifications (compliance with automotive and paint industry standards) may affect the price

Retail orders (1–5 kg): from several dozen to several hundred zlotys

Wholesale orders (25+ kg): custom pricing with a discount

Annual contracts (1,000+ kg): the most favorable pricing terms

Do you need zinc phosphate? Contact us!
Ask about current prices, availability, and wholesale discounts. We’ll respond within 24 hours.

Zinc phosphate—Where to buy? Ask for a quote!

Order a sample or request a wholesale quote

We offer free samples of zinc phosphate
(250–500 g) for application testing before placing a larger order. For B2B customers, we prepare customized quotes that take into account:

• – Order volume and frequency
• – Documentation and certification requirements (industrial paints, automotive, construction)
• – Special technical requirements (particle size, specific surface area, surface treatment)
• – Packaging and labeling requirements

Contact us—we’ll respond within 24 hours!

Zinc phosphate—a key component of modern coatings and materials

Definition and chemical formula of FePO₄

Zinc phosphate is an inorganic chemical compound with the formula Zn₃(PO₄)₂, which is the zinc salt of phosphoric acid. In industry, it is primarily found as a white crystalline powder with outstanding anticorrosive properties. This compound plays a key role in modern metal surface protection technologies, serving as one of the most important anti-corrosion pigments in industrial paint and coating systems

The industrial use of this raw material is based on three main pillars. First, as an anti-corrosion pigment, it effectively protects metal surfaces from corrosion, replacing toxic chromate and lead-based pigments. Second, in phosphating processes, it forms durable conversion coatings on steel and aluminum, providing an excellent primer for paints and varnishes. Third, as a functional filler in plastics, construction mortars, and adhesives, it improves mechanical properties and weather resistance.

Working with us as your supplier guarantees access to raw materials with consistent quality parameters, complete technical documentation compliant with industry standards, and technical support at every stage of integrating the product into your manufacturing processes. We offer grades tailored to specific applications in paints, coatings, plastics, and construction chemicals.

Chemical Characteristics and Properties

Chemical name, synonyms, and formula

This compound is known by many names depending on the industrial and scientific context. The chemical name according to IUPAC nomenclature is zinc phosphate (English), referred to in Polish as zinc(II) phosphate or zinc phosphate. In technical literature, the names zinc orthophosphate and tribasic zinc phosphate are also encountered.

The basic chemical formula is Zn₃(PO₄)₂, but in industrial practice, the hydrated form Zn₃(PO₄)₂·4H₂O (tetrahydrate) is most common. In nature, this compound occurs as the minerals phosphophyllite or hopeite, although industrial forms are produced synthetically to ensure consistent quality parameters.

In chemical catalogs and material safety data sheets, it is identified by CAS number 7779-90-0 (tetrahydrate) or CAS number 7543-51-3 (anhydrous form). The EINECS number is 231-944-3. These unique identifiers are essential for ordering the product and verifying compliance with legal requirements.

Physicochemical Properties

In its pure form, the compound is a white crystalline powder with a characteristic, slightly granular appearance. Technical-grade products may have a slightly grayish tint due to impurities or specific manufacturing conditions. The particle size in standard grades ranges from 1 to 15 micrometers; however, for paint applications, narrower fractions (2–5 μm) are often required to achieve optimal application properties.

Solubility in water
is practically zero (0.0014 g/100 mL at 20°C), making this pigment ideal for water-based and solvent-based systems—it does not leach out of the coating during service. However, the compound is soluble in mineral acids (HCl, H₂SO₄, HNO₃) and in solutions of strong bases.

The density
ranges from 3.04 to 3.998 g/cm³ depending on the crystalline form and degree of hydration. This high density translates to good hiding power in paint systems. Thermal stability
is very good—the compound remains stable up to a temperature of approximately 900°C, although in the 100–200°C range, it loses its crystallization water (the tetrahydrate transitions to the anhydrous form).

A key parameter for paint applications is the specific surface area (BET), which ranges from 3–15 m²/g for standard grades and can reach 20–40 m²/g for specialty grades. A higher specific surface area results in better anticorrosive properties but may also increase the viscosity of paint systems.

Available purities and product forms

Grades for paints and anti-corrosion coatings

For the paint and coatings industry, we offer zinc phosphate in specialty grades optimized for pigmentary and anti-corrosion properties. These products feature a strictly controlled particle size (typically 2–5 μm), which ensures optimal coverage, good dispersion in paint systems, and rheological stability.

Key parameters for paint formulators

• Zinc content: min. 48–50% Zn (calculated as metal)
• BET specific surface area: 10–25 m²/g (depending on the application)
• Particle size d50: 2–5 μm
• Oil absorption (per DIN 53199): 15–25 g/100 g
• pH of aqueous suspension (10%): 6.5–8.5
• Water-soluble content: max. 0.3%

The pigment in anti-corrosion paints acts in multiple ways. First, it passivates the metal surface by forming insoluble complexes with iron ions. Second, it raises the pH in micro-areas beneath the coating, inhibiting corrosion processes. Third, it improves the coating’s adhesion to the metal substrate by forming chemical bonds at the metal-organic phase interface.

It is used in anti-corrosion primers (typically 10–25% in the dry formula), primer paints for steel structures, and epoxy and polyurethane systems for the automotive, offshore, and infrastructure industries. It serves as a safe alternative to chromate (VI) pigments, which are classified as carcinogenic and subject to REACH restrictions.

Grades for plastics, composites, and construction chemicals

In plastics, the product acts as a functional filler and flame retardant. When added to polyamides, polypropylene, PVC, and epoxy resins, it improves the elastic modulus, reduces shrinkage after curing, and increases resistance to UV radiation and thermal aging. Typical dosages range from 5–20% by weight.

In construction chemicals, it is used as a component in concrete repair mortars, structural adhesives, and sealants. It acts as a corrosion inhibitor for steel reinforcement in concrete, particularly in chloride-containing environments (bridges, coastal structures, tunnels). Additionally, it improves adhesion to mineral and metal substrates.

In polymer-concrete composites, it increases resistance to chemicals (acids, bases, salts) and improves tribological properties (abrasion resistance). It is also used in floor coatings for the chemical and food industries, where high chemical and mechanical resistance is required.

Specifications for grades used in plastics and construction chemicals

• Purity: min. 95% Zn₃(PO₄)₂
• Particle size d50: 3–10 μm
• Moisture content: max. 1.0%
• Soluble matter content: max. 0.5%
• Color: white to slightly grayish

Standard and special packaging

Standard packaging:

• 1 kg, 5 kg – HDPE plastic containers (for laboratories, technical trials)
• 25 kg – paper bags with a polyethylene liner (industrial standard)
• Big bags 500–1,000 kg – for large industrial customers, with the option of palletization

Custom packaging upon request:

• Bags with an additional aluminum lining (for hygroscopic products)
• Individual packages of 10 kg and 15 kg (customized to the customer’s production lines)
• Labeling in foreign languages and with the customer’s logo (white label)
• Packaging in transport containers in accordance with ADR/IMDG requirements

Packaging and logistics:

• Standard pallet: 1,000 kg (40 bags × 25 kg) or 1 big bag
• Securing: stretch film, band, shipping labels
• Shelf life: 24 months from the date of manufacture (in original packaging)
• Storage conditions: dry location, temperature 5–30°C, protect from moisture

Industrial Applications

Anti-corrosion pigment in paints and coatings

This anti-corrosion pigment forms the foundation of modern anti-corrosion protection systems. Its mechanism of action is based on the passivation of metal surfaces through the formation of thin layers of insoluble iron and zinc phosphates, which effectively inhibit oxidation processes. Unlike chromate pigments (zinc chromate, strontium chromate), it contains no chromium(VI) and is safe for the environment and workers’ health.

In water-based and solvent-based paint systems, it serves a dual purpose. First, as a pigment, it provides passive protection by physically isolating the metal substrate from corrosive agents (water, oxygen, salts). Second, it provides active protection—upon contact with moisture, zinc and phosphate ions are released, which passivate areas of coating damage (scratches, chips), preventing the development of undercoating corrosion.

Typical applications in paints:

• Anti-corrosion primers for structural steel (bridges, machinery, steel structures)
• Primer paints in the automotive industry (frame, chassis, body parts)
• Coating systems for the offshore and marine industries (drilling platforms, ships, port structures)
• Paints for roofing and metal structures in construction
• Protective coatings for machine and equipment components exposed to moisture and chemicals

Dosage in paints:
typically 8–25% by dry weight of the paint (depending on anti-corrosion requirements). It can be used alone or in combination with other pigments (iron phosphate, aluminum phosphate, zinc oxide).

Phosphating and Conversion Coatings

Surface treatment of metals using the zinc phosphating method is one of the most important technologies for preparing substrates prior to painting in the automotive, household appliances, and machinery industries. It involves the formation of thin crystalline layers (1–10 μm) on the surface of steel or aluminum through a chemical reaction with a phosphating bath.

Mechanism of phosphating:

• Degreasing the metal surface (removal of oils and greases)
• Surface activation (increasing the number of crystallization sites)
• Phosphating bath—reaction of zinc and phosphoric acid with the metal surface
• Rinsing and passivation (sealing the layer)

The resulting phosphate layer is characterized by a microcrystalline surface with a high surface area, which drastically improves the adhesion of organic coatings (paints, varnishes, adhesives). Additionally, this layer itself acts as a corrosion barrier, especially when combined with preservative oils.

Applications of phosphate coatings:

• Car bodies (entire body before painting)
• Automotive components (suspension, engine parts, exhaust systems)
• Home appliances (washing machines, refrigerators, ovens—before powder coating)
• Fasteners (screws, nuts, washers—corrosion protection)
• Steel structural components exposed to harsh operating conditions

In phosphating processes, the preparation functions both as a component of the phosphating bath and as a reaction product that forms a protective layer.

Applications in plastics, adhesives, and construction chemicals

In the plastics industry, the compound is valued as a functional filler that improves the mechanical and thermal properties of polymers. In polyamides (PA6, PA66), an addition of 5–15% increases the elastic modulus by 20–40%, reduces the coefficient of thermal expansion, and improves creep resistance at elevated temperatures. In PVC, it is used as a synergist for calcium-zinc stabilizers, improving thermal stability during processing.

In structural adhesives (epoxy, polyurethane, acrylic), it acts as a filler that increases shear and peel strength. Additionally, it improves the adhesive’s resistance to chemicals and high temperatures. It is used in adhesives for bonding metals and composites, as well as in adhesives for the automotive and aerospace industries.

In construction chemicals, it is used as:

• A corrosion inhibitor for rebar in concrete (repair mortars, repair concretes)
• A component of epoxy mortars for anchoring bolts in concrete
• A filler in sealants for expansion joints
• A component of bonding primers for concrete and steel substrates
• A modifier in mortars for industrial floors (to increase chemical resistance)

Dosage:
3–10% in cement mortars, 5–20% in resin systems

Other specialized applications

The compound is also used in a number of industrial niche applications. In the electronics industry, it is used as a filler in conductive composites and EMI/RFI shielding materials. In technical ceramics, it serves as a component of glazes and enamels with enhanced chemical resistance. In fire-retardant systems, it acts as a synergist for flame retardants in plastics and intumescent coatings.

In the pharmaceutical and cosmetics industries, it can be used (in the appropriate pharmacopoeial purity) as a source of zinc in dietary supplements and as an ingredient in toothpastes with antibacterial properties. In agriculture, it is used as a fertilizer that provides phosphorus and zinc—micronutrients essential for proper plant growth.

Documentation and Quality Control

Safety Data Sheet (SDS) and Technical Specifications

Every batch we deliver comes with complete technical documentation compliant with REACH and CLP requirements. The Safety Data Sheet (SDS), prepared in accordance with Regulation (EC) No. 1907/2006, contains 16 sections covering: substance identification, hazard information, composition and information on ingredients, first aid, fire response, measures in case of accidental release, product handling and storage, exposure controls and personal protective equipment, physicochemical properties, stability and reactivity, toxicological and ecological information, waste management, transport information, and legal information.

The technical specification contains detailed product parameters relevant to the customer’s manufacturing process:

• Zinc content (% metallic Zn)
• Zn₃(PO₄)₂ content (% by weight)
• Particle size (d10, d50, d90)
• BET specific surface area (m²/g)
• Oil absorption (g/100 g)
• pH of aqueous suspension (10%)
• Moisture content (%)
• Water-soluble content (%)
• Color (on the CIE Lab* scale)
• Bulk density (g/l)

Documentation for bulk density (g/l) is available in Polish, English, and other EU languages upon customer request.

Certificate of Analysis and Batch Reproducibility

Each shipment is accompanied by a Certificate of Analysis (CoA) confirming that the product batch in question complies with the technical specifications. The certificate includes:

• Production batch number
• Date of manufacture and expiration date
• Test results for all parameters specified in the technical specifications
• Signature of an authorized representative and the manufacturer’s seal

Our quality management system guarantees repeatability of parameters between batches within ±2% for key indicators (Zn content, d50 particle size, BET surface area). This ensures that customers can rely on consistent application properties and eliminates the need to re-optimize formulations with each delivery.

Documentation retention
: All certificates of analysis are archived for a period of 10 years and are available upon customer request. The batch numbering system enables full product traceability from raw material to finished product.

Compliance with Industry Standards and Requirements

The product we supply meets the requirements of key industry standards:

Paint industry:

• ISO 3549:1995 – Pigments and fillers. Test methods for general properties
• ISO 787 (Parts 1–25) – Test methods for pigments
• ASTM D476 – Standard Classification System for Dry Pigments for Paint

Automotive industry:

• DBL 7389 (Daimler) – Requirements for anticorrosive pigments
• TL 226 (VW/Audi) – Requirements for surface preparation and coatings
• GSB (Saint-Gobain) – Pigment Quality Standards

Compliance with REACH regulations:

• Substance registered under REACH
• No SVHC (Substance of Very High Concern) substances
• Compliance with CLP requirements for classification and labeling

Upon customer request, we can provide certificates of compliance with specific industry standards and declarations of compliance with end-customer requirements.