CACO3 – CALCIUM CARBONATE 98%

Calcium Carbonate (CaCO3) — also known as Industrial Limestone Powder or Calcium Carbonate Powder — is a fine white inorganic mineral with the chemical formula CaCO3, CAS number 471-34-1, and molecular weight of 100,09 g/mol. It is the most widely used filler and coating agent in the paint, plastics, paper, rubber, and water treatment industries in Vietnam and globally. With its low cost, stable domestic supply, and high chemical inertness, industrial CaCO3 is an irreplaceable raw material in any factory's cost optimization strategy.

Technical Specifications of Industrial CaCO3

Industrial CaCO3 Classification: GCC and PCC

In the industrial market, CaCO3 is supplied in two main forms with distinctly different properties and applications. Choosing the right type directly affects product quality and cost efficiency.

GCC — Ground Calcium Carbonate

GCC GCC is produced by crushing and sorting natural limestone (calcite or marble) through several stages. It is the most common type in industry due to its low cost and abundant supply from domestic quarries in Hai Duong, Nghe An, and Binh Phuoc provinces. GCC is suitable for... medical filler In wall paints, PP/PE plastics, rubber, and building materials, where requirements for whiteness and particle size are not too stringent.

PCC — Precipitated Calcium Carbonate

PCC It is synthesized by a chemical method: limestone is heated to produce CaO, dissolved in water to form Ca(OH)2, and then reacted with CO2 to precipitate pure CaCO3. This process allows for precise control of particle shape (scalenohedral, rhombohedral, acicular) and particle size down to below 1 µm. PCC has GE brightness is whiter.With a larger specific surface area, it is suitable for coated paper, pharmaceuticals, cosmetics, and applications requiring high purity.

Applications of CaCO3 in Industry

Industrial-grade CaCO3 is used in most manufacturing sectors in Vietnam. Below are the main consuming industries and their specific technical roles:

• Paints & Building Materials: CaCO3 is an extender pigment, accounting for 15–40% by weight in water-based paint formulations. Its effects include reducing the need for expensive TiO2, improving coverage, increasing the mechanical strength of the paint film, and reducing shrinkage during drying. In mortar, lightweight concrete, and gypsum boards, CaCO3 helps reduce weight and improve workability.
• Plastics & Polymers (PP, PE, PVC): CaCO3 is added to the resin matrix from 10–50% to increase stiffnessThis reduces thermal shrinkage, improves mold fluidity, and significantly lowers compounding costs. In rigid PVC (water pipes, profile doors), CaCO3 with a mesh size of 1250–2500 also helps improve the surface and gloss of the product.
• Paper & Packaging: The application serves two purposes: Filler (mixed into pulp to increase weight and save fiber) and paints (A coating applied to the surface of coated paper to increase GE brightness, improve printability, and enhance surface gloss). PCC is preferred in premium printing and office paper due to its control over particle shape.
• Natural and synthetic rubber: CaCO3 acts as Reinforcing filler It is used as a semi-reinforcing filler in rubber, improving tensile strength, abrasion resistance, and reducing compounding costs compared to carbon black or silica. It is commonly used in the production of shoe soles, technical gaskets, conveyor belts, and molded rubber products.
• Water Treatment & Environment: Powdered or granular CaCO3 is used for raising the pH of acidic wastewater In textile dyeing, electroplating, and food processing plants, CaCO3 replaces NaOH at a much lower cost. In exhaust gas treatment, CaCO3 is injected into the combustion chamber to absorb SO2 and HCl (desulfurization process). It is also used in RO water remineralization to regenerate minerals.
• Animal Feed & Agriculture: Food-grade CaCO3 is Calcium supplement It is important in poultry, aquaculture, and livestock feed, supporting bone and eggshell development. In agriculture, limestone powder is applied directly to... reclaiming acidic soil (Raising soil pH), improving the structure of heavy clay soils, and providing calcium/magnesium to plants.

Why Choose Loc Thien CaCO3?

Loc Thien is a distributor of industrial chemicals in Ho Chi Minh City and Dong Nai, specializing in supplying CaCO3 to manufacturing plants in Southern Vietnam. Below are the reasons why procurement and technical departments trust Loc Thien:

• ✅ Various mesh sizes available upon request: Offering a full range of fineness from 325 mesh (44 µm) to 2500 mesh (5 µm), this allows engineers to precisely select the parameters suitable for each product formulation — without having to accept suboptimal particle sizes due to a lack of options.
• ✅ Whiteness control (GE Brightness ≥ 90%): Each batch undergoes GE brightness testing, ensuring color consistency in paint and plastic production—a crucial factor that helps QC avoid batch inconsistencies that could affect the finished product.
• ✅ Stock available in Binh Phuoc and Ho Chi Minh City: Permanent inventory helps shorten lead times, fulfill urgent orders, and allows for flexible production planning—without being dependent on import schedules or long-distance shipping.
• ✅ Bulk delivery in large bags, bulk order support: Packaging in 500–1.000 kg big bags reduces loading, unloading, and packing labor costs compared to 25 kg bags, suitable for factories with consumption scales of tens to hundreds of tons per month. Framework contracts on a quarterly or annual basis can be discussed.

Instructions for Using & Storing CaCO3

• Mixing ratios in water-based paints: Typically 15–40% by weight of the total formulation, depending on the target PVC (Pigment Volume Concentration) and the type of CaCO3 (GCC 325 mesh for general interior/exterior paints; GCC 600–1250 mesh for gloss or premium paints).
• Mixing ratios in resins: 10–30% for standard applications (films, resins, packaging); 30–50% in engineering plastics and rigid PVC compounds. Testing with an internal mixer or twin-screw extruder is recommended to determine the optimal loading.
• Preservation: Store in a dry, well-ventilated place, avoiding direct contact with water and high humidity. Fine powdered CaCO3 is highly hygroscopic and prone to clumping—once it becomes damp, its dispersion effectiveness in formulations is reduced. Storage temperature: room temperature (refrigeration not required).
• Safe to operate: Fine CaCO3 dust (especially particles of 1250 mesh or larger) can cause respiratory and eye irritation with prolonged exposure. The use of an N95 mask or dust respirator is mandatory when handling large quantities, especially in enclosed spaces. Wear safety glasses and gloves when necessary.
• Storage instructions: Do not store bags of CaCO3 near acidic chemicals such as HCl, H2SO4, HNO3 — CaCO3 reacts immediately with strong acids according to the equation CaCO3 + 2HCl → CaCl2 + H2O + CO2↑, releasing CO2 gas which can create pressure and be dangerous in confined spaces.

Frequently Asked Questions (FAQ)

What is the difference between CaCO3 mesh 325 and mesh 1250? Which one should I choose?

Mesh It is the particle size index: the higher the number, the finer the particles. Specifically, Mesh size 325 ≈ 44 µm strong khi Mesh size 1250 ≈ 10 µm — That is, the 1250 mesh particles are four times finer in diameter. This directly affects application efficiency:

• Common wall paint, plaster, and building materials: Using a 325–600 mesh is sufficient; it's cheaper and easier to distribute.
• Gloss paint, epoxy paint, metallic paint: A mesh size of 600–1250 is needed to ensure a smooth, even paint film, free from coarse particles that would dull the surface gloss.
• PVC profile, engineering plastic compounding: A mesh size of 1250–2500 is required to ensure even dispersion in the polymer matrix and a flawless product surface.
• Coated paper, pharmaceuticals, cosmetics: PCC is commonly used with tightly controlled particle sizes below 2 µm.

If the size is still undecided, Loc Thien's technical department can provide advice and offer sample sizes of various mesh sizes for evaluation before placing a large order.

Can CaCO3 replace BaSO4 (Blanc Fixe) in industrial paints?

CaCO3 and BaSO4 are both pigment extenders, but They are not completely interchangeable. In all cases, analysis is needed according to each criterion:

• Whiteness: CaCO3 and BaSO4 are comparable in terms of high brightness — both are suitable for white and light-colored paints.
• Oil absorption: CaCO3 has a higher oil absorption rate than BaSO4 (approximately 18–22 g/100g compared to 12–15 g/100g), meaning more oil/resin is needed for complete wetting—the formula needs to be adjusted when substituting.
• Chemical resistance: BaSO4 is much more resistant to dilute acids than CaCO3. In industrial paints exposed to acidic environments (chemical tank paints, factory floor paints), BaSO4 is superior because CaCO3 can be corroded over time.
• Cost: CaCO3 is significantly cheaper than BaSO4 — this is why many paint manufacturers replace some of BaSO4 with CaCO3 to optimize costs in acid-free products.

Conclusion: It is possible to partially replace (50–70%) BaSO4 with CaCO3 in conventional paints; retain BaSO4 for applications requiring high chemical resistance.

Why does CaCO3 in paint clump or settle quickly? How to fix it?

This is a common problem in paint manufacturing, usually due to two main reasons:

• Uneven particle size / too coarse: Low mesh CaCO3 (325 mesh) in fine latex paints will settle quickly because gravity overcomes the viscosity of the solution. Solution: switch to a higher mesh size (600 or 1250) or use stearate-coated surface CaCO3 (active CaCO3) to improve oil penetration and dispersion.
• Lack of dispersant or insufficient dispersion energy: CaCO3 does not disperse itself in water — a dispersant such as sodium polyacrylate or phosphate ester is needed at a level of 0,3–0,8% by weight of CaCO3. The correct procedure is: dissolve the dispersant in water first → slowly add CaCO3 → stir at high speed (cowles blade) for a minimum of 15–20 minutes to achieve the target fineness on the Hegman gauge before mixing it into the paint system.

If clumping occurs after storage, the cause is usually moisture in the CaCO3 during storage — warehouse conditions and shipping procedures need to be checked.