Talc

Talc (CAS 14807-96-6), also known by its food additive designation E553b and commercially as Steritalc, is a naturally occurring hydrated magnesium silicate mined and processed for industrial use.

Where is Talc used?

• Pharmaceuticals: glidant and lubricant
• Tablet compression: improves powder flow and prevents die sticking
• Personal care and cosmetics: texture control and moisture absorption in pressed powders and foundations
• Body powders: slip improvement
• Plastics: mineral filler that increases stiffness, reduces cycle times and lowers raw material costs in polypropylene compounds
• Food production: approved anti-caking agent for coating chewing gum, rice and dried goods
• It prevents clumping during storage and handling while maintaining product integrity.
• In plastic and composite systems, especially PP and PE, reduces shrinkage and increases rigidity and heat deflection temperature (HDT).
• In thermoplastic matrices such as polypropylene (PP), increases flexural modulus (stiffness), impact resistance and resistance to high temperatures, and minimizes shrinkage and warpage during injection molding.
• In cosmetic products, makes facial makeup opaque.
• In liquid systems, adjusts viscosity to prevent settling of pigments and heavy fillers and reduces brush marks during application.

Formulation notes

• Potential for contamination with asbestos; mining sites should be selected carefully and ore tested sufficiently.
• Calcite is a standard volume filler with spherical or cubic particle structure, while talc has a platy structure that provides flexibility, dimensional stability and superior barrier properties (water/moisture impermeability), whereas calcite is preferred for high filler loading and cost reduction.

Typical specification

• For cosmetics and pharmaceuticals, must have low fibrous and hard minerals and low arsenic and iron content.
• Specific surface area (BET) of 3 - 15 m²/g.
• pH of 8.5 - 9.5 in a 10% suspension.
• Industrial grade has a whiteness range of 70–100%.

Regulatory status

• Adoption of Carc. 1B H350 classification would significantly impact consumer products because REACH Annex XVII restriction No. 28 prohibits the sale of substances classified as category 1 carcinogens.
• This record covers talc containing less than 0.1% asbestos or crystalline silica.

Storage, packaging and handling

• Should be stored on wooden or plastic pallets in dry, cool and well-ventilated closed warehouse areas to avoid moisture.

Frequently asked questions about Talc

In which paint and coating applications is talc used?

It is used in the paint industry as a matting and barrier filler, especially in anti-corrosion industrial primers, marine coatings and decorative interior/exterior paints.

What functions does talc perform in rubber compounds?

It acts as a filler, insulator, and reinforcing agent in rubber, improving vulcanization, elasticity, and tensile strength.

Can talc be added to plastic films?

China plastic grade talc can be added to plastic film, especially PE film and polymer film, to increase hardness, durability, and transparency.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.