Difference Between Coated and Uncoated Calcium Carbonate

Introduction

The difference between Coated Calcium Carbonate and Uncoated Calcium Carbonate lies in the surface characteristics, applications, and physical specifications.

To learn more about Calcium Carbonate, click here.

First: Uncoated Calcium Carbonate

Uncoated Calcium Carbonate (CaCO₃) is the natural form of calcium carbonate that is ground without the addition of any chemicals or surface treatment. It possesses several properties that make it suitable for specific applications, particularly in industries that do not require surface modification.

Uncoated Calcium Carbonate Properties:

Dry and pure, with a color ranging from pure white to off-white or slightly grayish.
Insoluble (but reacts with acids to produce carbon dioxide).
Unmodified surface, tends to agglomerate when mixed with polymers or oils.
Lower cost compared to coated grades.

Uses of Uncoated Calcium Carbonate:

In the production of paints, paper, and inks.
In the manufacture of cement and construction materials.
In the production of ceramics and porcelain.
Added to animal feed as a source of calcium.
Used as a filler in low-grade plastics.

Second: Coated Calcium Carbonate (Treated CaCO₃)

It is the same calcium carbonate material (CaCO₃), but its surface is treated with stearic acid to form a hydrophobic layer, adding new properties that make it suitable for different industrial applications.

Properties of Coated Calcium Carbonate:
• Pure white powder.
• Insoluble in water.
• Modified surface prevents particle agglomeration.
• Reduces moisture absorption.
• Better compatibility with polymers such as PP, PE, and PVC.
• Enhances final product properties such as strength, smoothness, and transparency.

Uses of Coated Calcium Carbonate:
• In high-quality plastic industries (injection molding, extrusion, sheets).
• In the manufacturing of wires and cables.
• To improve the mechanical properties of polypropylene (PP) and polyethylene (PE).
• To reduce the consumption of petrochemical raw materials.
• In food packaging applications.

Brief Comparison:

Property	Uncoated (Non-treated)	Coated (Treated)
Dispersion in polymers	Poor	Excellent
Compatibility with plastics	Low	High
Agglomeration	Often occurs	Rare
Common applications	Paints, paper, cement	Plastics, cables, fillers

Also read about the uses of Calcium Carbonate in the paper industry
click here

The difference between coated and uncoated calcium carbonate lies mainly in the surface treatment and physical properties, which directly impact their performance in industrial applications. Choosing the right type depends on the end use, quality requirements, and cost considerations. A clear understanding of both types contributes to improved performance and productivity across various industries.

About the largest company in grinding and producing calcium carbonate Globe Stone Hills