Enhancing pressure comfort of a bra’s under-band

The under-band of a bra with line-shaped wings (“− −”) covers the underbust girth of a female body and determines the size of bra. The wearing pressure of an under-band has a direct impact on a bra’s comfort. In this article we used both subjective fit assessments and objective tension tests on bras of the same size and the same basic structure to explore the relationships between the structural parameters and the wearing pressures of under-bands, and to establish the equation for under-band length adjustment that enhances the pressure comfort and fit level. In the fit test, 100 bras of size 75B (US 34B)manufactured by one company were randomly selected, and classified by five professional models into five fit levels: tight, slightly tight, fit, slightly loose and loose. In the objective tests, the key structural parameters, i.e. the natural dimensions of under-band lengths and widths, of these samples were first measured, and then the tensions of the under-bands were tested on a tensile machine where the under-bands were stretched to the bras’ design size. Based on the bras’ equivalent pressure, the equation to predict the wearing pressure of the under-band was built on the structural parameters and the tension data. Using the “fit” bras identified in the fit test, a comfortable pressure range was established for bra comfortability assessment. Based on a comfortable pressure, the length of an under-band could be adjusted to keep its fit level as “fit” when the initial wearing pressure did not fall into the fit range.