Fiber Content of Blends of Cotton and Optically Brightened Polyester Determined by UV Fluorescence

Abstract

A new method is described for measuring fiber content of blends of cotton and optically brightened polyester using uv fluorescence as measured by a special uv meter. The intensity of the fluorescence is proportional to polyester content of the blend. A calibration curve is prepared using known blends, and unknown blends are determined by measuring fluorescence and referring to the calibration curve. Stock can be tested in the form of raw stock, sliver, roving, or yarn. The method is accurate and is simpler and faster than existing wet chemical methods. Fiber contents of 18 blends from a full-scale spinning project were tested by the fluorescence method and by the method recommended by the American Association of Textile Chemists and Colorists(AATCC). The coefficient of simple correlation of the results from the two methods was 0.997. Level difference between the methods was insignificant.