Generally, raw materials can be categorized into three grades: coarse, medium, and ultrafine. Coarse-grade materials feature larger particle sizes, making them difficult to disperse and prone to imparting a gritty texture; consequently, they are typically utilized in basic products where textural requirements are less stringent, or in formulations designed to achieve specific visual effects. The medium grade represents the most common application type; following appropriate milling processes, these particles disperse effectively within oil-and-wax systems. By striking a balance between cost-efficiency and performance, this grade is suitable for the majority of standard lipstick products.
Ultrafine-grade materials undergo high-intensity milling or air-jet pulverization processes, resulting in smaller particle sizes and a more uniform distribution. This allows them to form a more stable suspension within oil-based systems. Such materials can significantly enhance a lipstick's fineness and silky feel, ensuring more uniform color distribution and a more sophisticated finish; they are particularly favored in high-end matte lipsticks and products requiring high color payoff.
From a manufacturing perspective, higher degrees of fineness impose stricter demands on dispersion equipment-such as three-roll mills and high-shear emulsifiers. However, the corresponding improvements in product texture are also significantly more pronounced. Therefore, in the practical design of cosmetic formulations, it is essential to strike a careful balance among cost, processing complexity, and desired product performance.