Design And Development Of Conductive Weft Knitted Jacquard Products

Electrothermal fabrics are made of flexible fabrics with conductive materials.Effect of heating and keeping warm can be achieved once loading electrical circuit.It can be combined with a variety of traditional textile technologies and conductive materials,and has a broad application prospect in the fields of human body protection,thermal clothing,medical,wearable textiles,etc..Therefore,it will guide the design of electrical heating garments to reveal the relationship among the electrothermal property,fiber materials and fabric inner construction.The purpose of this paper is to design and develop three electrothermal weft knitting jacquard products.Firstly,9 conductive weft knitted jacquard fabrics with different proportion of conductive stitch numbers are developed by using silver-plated yarn and wool yarn.Then,the electrical and thermal properties of the fabrics were studied and the resistance model for weft knitted jacquard was established.According to the change rate of resistance under tensile,temperature requirement,yarn length used and appearance effects,the optimal structure of conductive weft knitted jacquard fabric was selected to be the electrical heating element of the product.Design 3 conductive weft knitted jacquard products and one electrical heating gilet was fabricated..The product was tested for electrical and thermal performance and evaluated for thermal comfort.The experimental results show that the resistance of the conductive jacquard weft knitted fabric has a linear relationship with the proportion of the number of loops.The resistance value decreases little and is stable within 60 min.Also,resistance value is stable under external tensions.Conductive weft knitted jacquard fabrics were tested for electrical and thermal performance.The results show that the equilibrium temperature of the fabric can reach 48.8~62.9 ?,and the thermal stability is satisfied,which meets the requirements of electric heating elements.Concerning the established weft knitted jacquard resistive model,results show that maximum absolute error between the theoretical value of resistance model and empirical value was 0.104?,maximum relative error was 6.42%,which was a high degree of agreement.It can be concluded that the resistance model can be used to predict the influence of jacquard pattern design onelectrical properties of conductive knitted fabrics.Conductive fabric which the proportion of conductive stitches is 60% is selected as the heating element of the electrical heating gilet.The temperature of heating area is even and increases rapidly,and the temperature could reach about47.3 ?,which will meet the requirements of human thermal comfort.