Sewing is the major contributor to the manufacturing of protection wear for the survival of early human civilization against extreme weather conditions. Mechanized sewing witnessed developments during the middle of the 19th century, and tedious handwork was replaced by sewing machines. Despite the modernization of sewing machine technologies, speed, material thicknesses, automation, and the introduction of AI in sewing, there is a longstanding problem of heat loss along stitch lines. The sewing material is compressed by the sewing thread, and this compression results in a bridge between the human body and the external cold environment. Garment technologists identify this problem and due to the lack of any technological solution, the problem is solved through complex material handling methods. A new sewing technological solution has been developed to solve this problem, called spacer stitching, which addresses the problem of compression along stitch lines. Two baffled jackets with sewn-through methods are prepared, one with the spacer stitching technology and the other with conventional sewing. Thermal resistance and insulation efficiency are evaluated using the Thermetrics thermal manikin “Sonny” under dynamic (walking) conditions to analyze the thermal resistance difference between the two types of sewing methods as well as the effects of motion on insulation. The results reveal that the jacket made with spacer stitching demonstrates significantly higher thermal resistance and enhanced wearer comfort compared to that produced using conventional methods. Additionally, variations in thermal resistance are observed across different zones of the thermal manikin. These findings highlight the potential of spacer stitching to improve thermal insulation and revolutionize high-performance outerwear design.
Thermo-physiological comfort of automotive seating is governed by the complex interaction between seat-cover materials, their structural configuration, and the heat and moisture exchange occurring at the seat–body interface during prolonged sitting. While numerous studies have examined individual textile constructions or isolated comfort parameters, integrated evaluations combining objective material testing with dynamic microclimate measurements under realistic loading conditions remain limited. This study thoroughly examined six commercially important vehicle seat-cover materials that represent laminated, warp-knitted, and woven polyester architectures. Standardized laboratory techniques were used to quantify objective comfort qualities, such as air permeability, water vapor permeability, thermal resistance (Rct), and evaporative resistance (Ret) and transient heat flux test (H-test). Simultaneously, a multi-sensor system was used to constantly monitor temperature and relative humidity at the seat–body interface during sitting loading in a controlled subjective microclimate experiment at room temperature. The findings show that lamination technique and textile structure have a major impact on both transient microclimate behavior and steady-state material properties. Increased air and moisture transmission in warp-knitted and more open structures resulted in reduced evaporative resistance and more stable microclimate conditions. Denser laminated structures, on the other hand, exhibited more resistance to heat and evaporation, which led to a greater buildup of moisture when they were seated. Different temporal responses in temperature and humidity were also shown by the multi-sensor microclimate studies, underscoring the significance of assessing comfort beyond static material metrics. This study demonstrates that static thermos-physiological parameters alone are not sufficient to predict real stated comfort behavior. By integrating time-resolved microclimate analysis under realistic seated loading with standardized testing, a more reliable evaluation framework for automotive seat-cover comfort is proposed.