The composition of coatings used in coating processes mainly consists of adhesives, pigments, and other auxiliaries. The coating itself is a complex compound that varies based on specific paper requirements and formulations. Auxiliaries play a crucial role in the preparation of paper coatings.

The dispersing agent, often considered as surfactants, is one of the most significant auxiliaries in paper coatings. Its main functions include:

1. Imposing a charge on each pigment particle to create a repulsive force between them.

2. Covering the surface of each pigment particle, acting as a protective colloid.

3. Forming a high-viscosity state around the particles to prevent individual particles from agglomerating.

During coating, the dispersing agent is generally added to the coating formula to avoid the coating layer becoming too thick and uneven. The overall function of the dispersing agent is to ensure that the pigment in the coating does not flocculate and settle. This helps maintain low viscosity in the coating, providing good fluidity and coating adaptability. It also improves the miscibility of the adhesive and pigment, ultimately enhancing the surface strength and printing adaptability of the coated paper. To use the dispersing agent, it is first dissolved in water, and then the pigment is added.

When using blade knife coaters and rod coaters, it is essential to use high solid content coatings to improve speed and energy efficiency. Polymer organic dispersing agents are typically employed, such as sodium polyacrylate solution, sodium polymethacrylate and its derivatives, or disodium salt solution of diisobutene and maleic anhydride copolymer. Additionally, alkyl phenol polyoxyethylene ether and fatty alcohol polyoxyethylene ether are commonly used. Surfactants with a higher HLB value (10 ~ 20) are generally preferred, with a dosage ranging between 0.1% and 3.0%.

Our company specializes in providing chemical solutions for paper coating. The most widely used dispersing agent for paper coating is polyacrylate, and we have a stable supply capacity that has been serving customers worldwide for over 10 years, earning a good reputation.

Polyacrylates exhibit high resistance to high pH values, high temperatures, and high shear, with good placement stability. They are especially suitable for pigments based on CaCO3 and are widely used as dispersing agents for various pre-dispersed pigments. The addition of polyacrylate dispersing agent can improve the effects of blade marks, screening difficulties, and rheological fluctuations. Among the factors affecting the pigment dispersion process and the stability of the slurry after dispersion, the performance of the dispersing agent is undoubtedly the most important.