Paper manufacturing is a complex process where additives play a crucial role in determining the final quality and performance characteristics of the paper product. Among these, sizing agents are fundamental, primarily used to control the interaction of paper with liquids, most notably water and ink. While internal sizing affects the bulk of the paper sheet, surface sizing targets the paper's surface properties, directly influencing its printability, surface strength, and resistance to moisture penetration.

Alkylketene Dimer, commonly known as AKD, is a widely used synthetic sizing agent, particularly effective in alkaline or neutral papermaking processes. It is frequently supplied in liquid emulsion form, making it convenient for integration into modern paper machine systems. One such product available is a liquid AKD emulsion, typically offered at concentrations such as 20% or 30% solid content. This milky white to yellowish liquid, identifiable by its CAS number 144245-85-2, serves as a powerful surface sizing agent for a variety of paper grades.

AKD functions by reacting with the cellulose fibers on the paper surface under heat, forming a hydrophobic layer. This reaction significantly enhances the paper's resistance to water penetration, which is critical for preventing ink bleed and ensuring sharp text and images during printing. The use of AKD liquid in surface sizing contributes directly to improving the paper's surface printing strength, allowing for better performance with various printing techniques.

The advantages of using AKD liquid extend beyond just water resistance and printability. Implementing AKD as a surface sizing agent can lead to significant improvements in the physical strength properties of the paper. This includes enhanced folding endurance, improved breaking length, and increased ring pressure strength. These mechanical properties are vital for the durability and usability of the paper, especially for applications like packaging paper and card paper where structural integrity is paramount. Furthermore, AKD sizing helps in increasing the paper's smoothness and overall surface strength, which reduces phenomena like fiber shedding and dusting during handling and printing, leading to a cleaner process and higher quality output.

A notable benefit highlighted by modern AKD formulations is their ability to simplify the surface sizing process. Some advanced AKD compound surface sizing agents can directly interact with ordinary starch used in paper sizing, eliminating the need for modified starch or viscosity reducers that are often required in traditional methods. This not only simplifies the operation process but also offers a more stable product application. Moreover, such formulations can potentially replace oxidants historically used in oxidized starch production, contributing to a reduction in pollution and preventing equipment corrosion, aligning with increasingly stringent environmental regulations and sustainability goals in the industry.

The application of AKD liquid involves adding the product to a mixing tank and blending it with the slurry, typically recommended for use within a few hours. Alternatively, continuous online addition using a metering pump is a common practice for better control and efficiency. The recommended dosage can vary depending on the specific paper grade and desired sizing effect, often ranging from 0.4% to 3% based on the dry weight of the pulp. Maintaining a suitable system pH, generally between 7.0 and 8.5, is important for optimizing the performance of the AKD emulsion and ensuring effective sizing reaction.

AKD liquid is versatile and finds application across a wide spectrum of paper products. It is effectively used in the production of cultural paper, which includes writing and printing papers, packaging paper for boxes and containers, card paper for various uses, and specialized papers requiring specific surface characteristics. Its cationic nature in emulsion form helps in its retention on the anionic cellulose fibers, ensuring efficient deposition on the paper surface.

Proper storage and transport are essential for maintaining the quality and efficacy of AKD liquid. It should be stored in a cool place, typically between 4 and 30 degrees Celsius, away from freezing temperatures and direct sunlight. Transport requires sealed containers to prevent contamination and also avoidance of prolonged sun exposure. Packaging is commonly available in large drums, such as 200kg or 1000kg plastic drums, catering to different production scales.

In summary, AKD (Alkylketene Dimer) liquid emulsion is a highly effective surface sizing agent for the paper industry. Its ability to impart excellent water resistance, improve printing strength, enhance physical properties, and simplify the sizing process makes it a valuable additive for producing high-quality paper. As a leading manufacturer and supplier of chemical products, NINGBO INNO PHARMCHEM CO.,LTD. is dedicated to providing reliable and high-performance solutions for paper making. For those looking to buy or purchase AKD liquid emulsion, inquiries regarding price and availability are welcome. We strive to offer competitive pricing and ensure a consistent supply of this essential paper chemical, supporting our customers' production needs with quality products like AKD liquid.