Technical applications of sodium feldspar as frit in the ceramic and glass industry

In the modern industrial production system, sodium feldspar (NaAlSi₃O₈) has become an indispensable key material in the field of ceramic and glass manufacturing due to its unique physical and chemical properties as a frit. Its excellent fluxing performance, stable chemical properties and significant cost advantages have made it occupy an important position in the global industrial raw materials market. This article will analyze the specific role of sodium feldspar as a frit in two core application areas from a technical perspective.

Application in the ceramic industry

In the ceramic industry, sodium feldspar is mainly used in the body and glaze system to play a role in fluxing, reducing the firing temperature, and improving the quality of the glaze.

Fusing effect

Sodium Feldspar begins to melt in the range of 1100℃～1250℃, forming a low-viscosity glass phase, and forming a eutectic with clay, thereby reducing the firing temperature of ceramics. Studies have shown that the introduction of 15%～25% sodium feldspar in the ceramic body formula can reduce the firing temperature by 50℃～100℃, effectively reducing energy consumption.

Improving body density

Sodium Feldspar contains a certain proportion of Na₂O, which can promote body sintering and improve the density and flexural strength of the product. Experimental data show that adding 20% sodium feldspar to the porcelain tile formula can increase the flexural strength by about 15%～20%.

Optimize glaze performance

As a glaze flux, sodium feldspar can promote uniform melting of the glaze surface, improve the transparency and glossiness of the glaze surface, and improve the chemical corrosion resistance of the glaze surface. Especially in the formula of transparent glaze, bright glaze and low-temperature glaze, the dosage of sodium feldspar is usually 10% to 30%, which can effectively improve the decorative effect and durability of the product.

Application in glass industry

In the glass industry, sodium feldspar is an important flux raw material, participating in the glass melting process together with quartz, soda ash, etc. Its main functions include lowering the melting temperature, improving the transparency of glass and enhancing chemical stability.

Lowering the melting temperature

Sodium Feldspar is rich in Na₂O, which can effectively lower the melting temperature of glass, improve melt fluidity and reduce fuel consumption. In the glass formula, the amount of sodium feldspar is generally 10% to 25%, which can reduce the melting temperature by 100℃ to 150℃ and significantly improve the melting efficiency.

Improving glass transparency

Because sodium feldspar has a low iron impurity content (Fe₂O₃ is generally less than 0.15%), it can effectively reduce the coloring effect during the glass melting process and improve the optical properties of transparent glass. In the production of high-transmittance glass and liquid crystal display glass (LCD Glass), selected low-iron sodium feldspar is often used to ensure the high purity and transmittance of the product.

Improve the chemical stability of glass

Al₂O₃ in sodium feldspar can improve the acid and alkali resistance and thermal stability of glass, making the product more durable and less prone to weathering. In the formula of heat-resistant glass and chemical anti-corrosion glass, the addition amount of sodium feldspar is usually 15% to 20% to enhance the chemical stability and thermal shock resistance of glass.

Conclusion

As a frit material, sodium feldspar plays a key role in the ceramic and glass industries, not only reducing production energy consumption, but also improving the mechanical properties and chemical stability of products. Henan Ankai New Materials Co., Ltd. has become an important partner of domestic and foreign ceramic and glass companies with its high-quality raw materials and advanced technology, providing the industry with high-purity, low-iron, high-stability sodium feldspar raw materials to help the industry upgrade.