Dimensional instability of socks

Abstract

Men‘s plain socks were designed and manufactured on an automatic hosiery machine with a cylinder diameter of 95 mm (3 % inch) which knitted with 108 needles. Four sizes of 10, 11, 12 and 13 were made for spring and autumn season. The socks were manufactured in plated plain jersey from a 50 tex cotton yarn and a 168 dtex PA 6 filament yarn whose characteristics were insufficiently known. The cuff contained an interlaced elastane yarn with a count of 54 tex. Principal yarn properties were measured before and after knitting and after 10 washing cycles at a temperature of 95 °C. Sock weight and knit fabric parameters in the sock as well as four most important sock dimensions before and after washing were measured. The height of the sock leg, the length of the sock foot and half of the leg circumference and half of the foot circumference were measured. Stretching properties of the yarn were essentially different before knitting and after 10 washing cycles. Cotton yarn breaking force was higher after 10 washing cycles up to 27.47 %. PA filament breaking force and stretching was lower up to 59.54 % after 10 washing cycles. The socks shrank longitudinally and transversally after 10 washing cycles from 11 to 19.14 % and they did not have the same size after the washing procedure. Due to thermal instability of the PA 6 filament thread it is recommendable to use cold washing.