HQ-G6867 Surface Sizing Agent is a cationic sizing agent synthesized from styrene-acrylate copolymer. It organically combines with starch, imparting the starch coating with excellent cross-linking strength and hydrophobicity. With no curing period required, it achieves 100% retention on paper, ensuring optimal sizing efficiency. During synthesis, a proprietary functional monomer is incorporated, delivering stable water resistance that prevents moisture regain in high-strength corrugated paper while stabilizing ring crush strength and enhancing paper fold endurance. Applicable Scope:Containerboard, corrugated paper, cardboard, whiteboard paper. Product Features: 1.The cationic groups in HQ-G6867 surface sizing agent adsorb onto sites activated by aluminum sulfate or ​cationic polymers within the paper layer, forming a ​continuous film that imparts excellent water resistance​ and ​ring crush strength to the paper. 2.Exhibits strong affinity and retention with fibers during sizing, while maintaining compatibility and synergy with starch, dyes, and other additives. 3.When combined with starch for surface sizing, it reduces starch consumption and costs. Sized paper demonstrates low surface absorbency and rapid post-drying curing. Incorporated with proprietary functional monomers, it significantly enhances burst resistance, folding endurance, and ring crush strength of containerboard and high-strength corrugated base paper, effectively suppressing moisture regain and sizing degradation.