Water resistance is a critical attribute for a vast array of paper products, from writing papers that prevent ink bleed to packaging materials that protect contents from moisture. NINGBO INNO PHARMCHEM CO.,LTD. delves into the scientific principles that make Alkyl Ketene Dimer (AKD) emulsion an exceptional agent for improving water resistance in paper.

The mechanism by which AKD enhances water resistance is rooted in its chemical structure and reactivity. AKD is an alkyl ketene dimer, a molecule characterized by a hydrophobic carbon chain and a reactive ketene dimer group. When AKD emulsion is introduced into the papermaking process, typically at the wet end or as a surface treatment, the reactive ketene dimer group undergoes a reaction with the hydroxyl groups present on the cellulose fibers of the paper. This reaction forms ester linkages, effectively attaching the hydrophobic AKD molecule to the fiber surface. This process creates a continuous, non-polar (hydrophobic) layer that repels water molecules, preventing them from being absorbed by the paper fibers.

The degree of water resistance achieved with AKD is influenced by several factors, including the dosage of AKD, the pH of the papermaking process, and the curing conditions. AKD functions most effectively in neutral to slightly alkaline environments, where its reaction with cellulose is optimized. Higher temperatures, particularly in the drying section of the paper machine, accelerate the curing process, ensuring that the hydrophobic layer is permanently bonded to the fibers. NINGBO INNO PHARMCHEM CO.,LTD. supplies high-quality AKD emulsions that are formulated for maximum reactivity and stability, ensuring consistent water resistance results.

Beyond basic water repellency, the improved water resistance provided by AKD also contributes to other desirable paper properties. It enhances printability by controlling ink spread, reduces dusting and fuzzing, and improves the dimensional stability of the paper. For paper mills, selecting the right sizing agent is crucial, and the advanced performance of AKD makes it a preferred choice. The ability to buy AKD from a reputable supplier like NINGBO INNO PHARMCHEM CO.,LTD. ensures access to a reliable solution for achieving superior water resistance in paper, meeting the stringent demands of the market.