Fluorine-free Water- and oil-resistant Coating Composition and Coating Solution, Coating Layer, and Product Comprising the Same

A fluorine-free water- and oil-resistant coating composition comprising:

• 30 wt % to 97 wt % biodegradable polymer in dry weight;
• 0.1 wt % to 25 wt % crosslinking agent in dry weight;
• 25 wt % or less of nanoparticles;
• 15 wt % or less of plasticizer;
• and
• 15 wt % or less of surfactant;
• 1 wt % or less of antifoaming agent in dry weight,
• wherein a coating layer comprising the fluorine-free coating composition has a water resistant property of a Cobb60 value of less than 10 g/m according to the ISO 535 method and a grease resistant property of a kit rating at least 7 according to the TAPPI T-559 method.