Alkyl ketene dimer (AKD) is most common neutral/ alkaline sizing agent. It is an Internal sizing agents. Structurally, it is unsaturated lactones and it is synthesized from fatty acids. Physically it is waxy like milky emulsion chemicals. It has less corrosive to the papermaking machine than acid sizing. For cultural paper and packing paper. CM Chemical has developed the following products. Advantage Alkaline sizing system reduces corrosion of paper machine equipment. Less foam produced by the approach system than the acidic rosin system. AKD pulp sizing cost less than rosin sizing. Hard- sizing can be applied, and the stocking sizing degree is proportional AKD usage. Features Mature production process, easy application, simple adding equipment. High self-retention, good sizing effect, fast curing rate. Strong anti-interference and good stability. Good anti-moisture effect for the paper, can effectively prevent the reduction of RCT.