Absorbency determines how effectively toilet paper captures moisture, a key trait for personal hygiene. The paper’s porous structure and fiber density dictate its liquid retention capacity. High-absorbency variants are often multi-layered, with air pockets between plies to boost retention. This feature is crucial for preventing disintegration during use, especially in wet conditions. However, excessive absorbency may compromise biodegradability, as chemical additives like wet-strength resins are sometimes used. Testing standards (e.g., ISO 12625) quantify absorbency rates, guiding manufacturers in optimizing this balance.