Alkylketene dimer is widely used in the paper industry as a sizing agent to improve the water resistance of paper products. It reacts with the hydroxyl groups in cellulose fibers, creating a hydrophobic surface that prevents ink and water from penetrating the paper. This application is particularly important in the production of packaging materials, writing papers, and printing papers, where durability and print quality are essential. Additionally, it is valued for its efficiency, stability, and ability to work effectively in neutral or alkaline conditions, making it a preferred choice in modern paper manufacturing processes.