Many people have experienced this: soft, skin-friendly pure cotton single jersey T-shirts or undergarments gradually lose their supple feel after several high-temperature washes, becoming dry, stiff, and rough to the touch-sometimes even causing an itchy sensation when worn against the skin. While many assume this is simply due to the garment aging or deteriorating, the stiffening of pure cotton single jersey after high-temperature washing is actually the result of an interplay between the cotton fiber structure, the fabric's knitting characteristics, and the washing conditions; it is a common phenomenon regarding fabric performance changes.
Pure cotton single jersey features a knitted loop structure characterized by high loft and significant spacing between fibers, relying on the natural softness of cotton fibers and internal air pockets to provide a comfortable feel. Cotton fibers are composed of natural cellulose containing numerous hydrophilic groups; during normal-temperature washing, the fibers absorb water, swell, and expand, allowing them to retain a relaxed, soft state after drying. However, in high-temperature washing environments, cotton fibers undergo irreversible thermal shrinkage. Their internal structure tightens and becomes taut, causing the originally lofty fabric to become dense and rigid-a change that is immediately perceptible as a stiff texture.
Furthermore, during the dyeing and finishing process, small amounts of softening agents and moisturizing ingredients are often retained in the fabric to counteract the naturally dry, rough texture of cotton fibers. These softening agents generally have poor heat resistance and are rapidly lost or decomposed when subjected to repeated hot water rinsing and high-temperature heating. Once these agents are removed, the inherent roughness and surface fuzz of the cotton fibers are fully exposed; deprived of this lubricating buffer, the fabric feels noticeably dry and stiff.
In addition, high-temperature washing accelerates fabric shrinkage and loop deformation. Because single jersey has a loose knitted structure, the loops tend to compress, stack, and set into a fixed shape under high heat, preventing them from returning to their original, lofty state. Simultaneously, limescale from the water and detergent residues can lodge in the gaps between fibers; as these accumulate, they increase the fabric's roughness, further exacerbating the issues of stiffness and matting. To preserve the soft texture of pure cotton jersey, opt for gentle washing in warm water and avoid high-temperature boiling or prolonged tumble drying. Promptly hang the garment to dry after washing and gently stretch the fabric to loosen the knit loops; these steps effectively prevent the fabric from becoming stiff or rigid, thereby extending the period during which the cotton knit remains comfortable to wear.