​​​​Zinc Oxide, Zinc White, Chinese White, 1314-13-2

​​​​Zinc Oxide, Zinc White, Chinese White, 1314-13-2

ZINC OXIDE (ZnO)
PRODUCT IDENTIFICATION INFORMATION

CHEMICAL STRUCTURE

Zinc Oxide (ZnO)

Zn⁺² — O⁻²

Molecular Formula: ZnO
SMILES: [Zn]=O
InChI: InChI=1S/O.Zn
Structure: Hexagonal wurtzite crystal structure (most stable form); cubic zinc blende structure also exists.

SECTION 1: CHEMICAL IDENTITY AND DESCRIPTION

SECTION 2: PHYSICAL AND CHEMICAL PROPERTIES

SECTION 3: CHEMICAL PROPERTIES AND REACTIVITY

SECTION 4: ZINC COMPOUNDS COMPARISON

SECTION 5: PRODUCTION METHODS

Method 1: Direct (American) Process

Reaction: Zn(vapor) + O₂ → ZnO

Description: Zinc metal ore (zinc lead or scrap zinc) is heated with coke in a furnace; Zinc vaporizes and reacts with oxygen in the combustion chamber to form ZnO; Rapidly cooled and collected as powder. The product is of lower purity and coarser particle size.

Method 2: Indirect (French) Process

Reaction: 2Zn + O₂ → 2ZnO

Description: Metallic zinc is vaporized in a furnace; Zinc vapor reacts with hot air or oxygen to form ZnO; High purity (≥99.8%) and fine particle size product is obtained. This is the most commonly used method.

Method 3: Chemical (Wet) Process

Reaction: ZnSO₄ + Na₂CO₃ → ZnCO₃↓ + Na₂SO₄; ZnCO₃ → ZnO + CO₂ (calcination)

Description: Zinc sulfate solution is treated with sodium carbonate; Zinc carbonate is precipitated, filtered, and calcined to obtain ZnO. Provides high purity and controlled particle size.

Method 4: Hydrothermal / Sol-Gel Synthesis

Process: Zn-salt + Alkali → Zn(OH)₂ → ZnO (hydrothermal / sol-gel)

Description: Zinc salt (usually acetate or nitrate) solution is reacted with alkali to precipitate zinc hydroxide; The precipitate is washed and converted to ZnO nanoparticles via hydrothermal or sol-gel methods under controlled conditions. Used for nanotechnology and advanced applications.

SECTION 6: FUNCTIONAL PROPERTIES AND MECHANISM OF ACTION

SECTION 7: MAIN APPLICATION AREAS

SECTION 8: QUALITY SPECIFICATIONS (TECHNICAL GRADE)

SECTION 9: TOXICOLOGICAL PROFILE

SECTION 10: GHS CLASSIFICATION AND LABELING

GHS Classification (in accordance with CLP and UN GHS):

Signal Word: WARNING

Hazard Pictograms: GHS07 (Exclamation Mark)

Hazard Statements (H-Codes):

NFPA 704 Hazard Classification:

SECTION 11: PRECAUTIONARY STATEMENTS (P-CODES)

SECTION 12: FIRST AID MEASURES

SECTION 13: FIREFIGHTING MEASURES

SECTION 14: STORAGE AND SHELF LIFE

SECTION 15: PACKAGING OPTIONS

SECTION 16: TRANSPORT INFORMATION

SECTION 17: REGULATORY STATUS

SECTION 18: OTHER NAMES AND SYNONYMS

SECTION 19: SUMMARY TABLE

SECTION 20: CRITICAL WARNINGS AND BEST PRACTICES

CRITICAL WARNINGS:

• Causes skin irritation (H315). Avoid skin contact. Wear protective gloves.

• Causes serious eye irritation (H319). Wear eye protection. In case of eye contact, rinse with plenty of water.

• May cause respiratory irritation (H335). Avoid inhalation of dust. Inhalation may cause metal fume fever (zinc shakes). Use in well-ventilated areas.

• Amphoteric. Reacts with both acids and strong alkalis. Avoid contact with incompatible substances.

• Not hygroscopic but may carbonate with CO₂ (slowly). Keep containers closed.

• Not flammable. However, fine dust may form explosive mixtures in air. Avoid dust formation.

• Incompatibilities: Strong acids, strong alkalis, aluminum and magnesium powders (at high temperatures).

• Hygiene Requirement: Wash hands thoroughly after handling. Prevent dust formation.

• Nano-sized zinc oxide: May exhibit higher reactivity and potential toxicity. Requires special PPE and exposure control.

BEST PRACTICE RECOMMENDATIONS:

Rubber Industry: Use as an activator in rubber vulcanization; Increases vulcanization speed and efficiency; Improves cross-linking; Recommended dosage (3-10 phr ZnO per 100 phr rubber); Active zinc oxide (high surface area) provides effectiveness at lower dosages.

Cosmetics and Sunscreens: Use as a broad-spectrum UV filter (UV-A and UV-B); Nano-sized ZnO provides transparent protection, while micro-sized ZnO leaves a white residue; Used at concentrations of 10-25%; Antimicrobial properties provide preservative effects.

Paints and Coatings: Use as an opacifying white pigment (Zinc White); Preferred in oil paints, enamels, and art materials; Less opaque than TiO₂ but softer and more stable; Also used in antimicrobial coatings.

Ceramics and Glass: Use as a flux in ceramic glazes; Lowers melting temperature; Provides gloss and durability in glazes; Serves as an opacifier; Used at 1-5% in glass formulations.

Electronics: Use as an n-type semiconductor (wide band gap 3.37 eV); Used in transistors, diodes, sensors, LEDs, and photodetectors; Ideal for thin-film transistor (TFT) and transparent conductive oxide (TCO) applications; Nanoparticles used in printed electronics.

Agriculture: Use as a fertilizer additive to remedy zinc deficiency; For soil and foliar applications; Recommended application (soil): 5-10 kg/da; Foliar: 0.5-1.0% aqueous suspension.

Handling: Use in well-ventilated areas; Avoid dust formation; Wear protective gloves, safety goggles, and appropriate respiratory protection (N95/FFP2 or higher).

Personal Protective Equipment: Protective gloves (nitrile, neoprene, butyl), safety goggles (chemical splash protection), protective clothing, NIOSH-approved N95 or higher dust mask (for respirable dust), local exhaust ventilation.

Hygiene: Wash hands thoroughly after handling; Do not eat, drink, or smoke while using; Remove contaminated clothing and wash before reuse.

Storage: Store in tightly closed, properly labeled containers in dry conditions; Keep away from acids and oxidizing agents; Protect from moisture and CO₂.

Spill Management: Avoid dust formation; Vacuum or wet-sweep (to prevent dust dispersion); Place in closed containers; Do not allow entry into drains or waterways.

Disposal: Dispose of in accordance with local, regional, and national regulations; Zinc oxide is considered non-hazardous waste; Recovery is possible.

SPECIAL NOTE ON RUBBER VULCANIZATION:

Zinc oxide is an essential activator in rubber vulcanization (with sulfur):

• Function: Activates sulfur vulcanization accelerators (e.g., MBT, CBS) and increases efficiency.

• Mechanism: Zinc oxide reacts with stearic acid to form zinc stearate, which activates the vulcanization accelerator.

• Dosage: 3-10 phr ZnO per 100 phr rubber (active ZnO can be used at lower dosages, 2-5 phr).

• Advantages: Provides vulcanization at lower temperatures and shorter times; Enhanced physical properties (tensile strength, elasticity, abrasion resistance).

• Nano ZnO: Can be used at reduced dosages (up to 50% less) due to higher surface area; Provides more homogeneous dispersion.

SPECIAL NOTE ON SUNSCREENS AND UV PROTECTION:

Zinc oxide is widely used as a broad-spectrum UV filter in sunscreens:

• Mechanism: Absorbs and reflects UV-A (315-400 nm) and UV-B (280-315 nm) radiation. Provides broad-spectrum protection.

• Concentration: Typically 10-25%.

• Nano vs. Micro: Nano ZnO provides transparent protection with no white residue; Micro ZnO gives a white color (Zinc White) and provides higher reflection.

• Advantages: More stable, photostable, lower allergenic potential than chemical UV filters, provides antimicrobial protection.

• Safety: FDA and EU approved; Very low systemic absorption; Considered safe on the skin.

LEGAL DISCLAIMER:
The information provided in this document is based on our current knowledge and experience and is presented in good faith. However, as all conditions of use are beyond our control, it does not constitute a binding specification or warranty. This Technical Data Sheet is for informational purposes only. Users are responsible for testing the suitability for their own applications. For complete safety, storage, use, handling, waste, and regulatory compliance information, please refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier.