In response to research that shows that consumers are interested in the concept of winter jeans, Invista, the Wichita, Kan., integrated producer of polymers and fibers, recently launched two new Thermolite® brand technologies. Denim fabrics made with Thermolite® Infrared technology increase their temperature when exposed to solar or artificial light. Special ceramic pigments are added to the fiber that transfer the energy of infrared rays into heat the body can feel. The patented Thermolite Dual Layer technology structure creates open spaces within the fabric, trapping air to help keep the wearer warm.