Optical Measurement of Non-Lint Particles in Various Grades of Cotton

Abstract

Electronic image-scanning instrumentation was developed to obtain objective measurement of the number and physical features of non-lint particles found on the surface of raw cotton samples. Characteristic size-distribution curves were defined for several grades of United States cotton. All grades of cotton tested were found to contain trash particles of comparable dimensions, with a prevalence of fine particulates less than one millimeter in size. Grade distinction was possible when comparisons were made on the basis of total particle count or the total length and area of the non-lint materials populating the cotton sample. Particle density computed as an index of percentage non-lint particles present on the optically contrasting lint surface of the cotton sample was found to be reliable for rating the relative trash content of cotton. A comparison of non-lint properties of universal grade standard cottons with classer-graded cotton samples showed that the classer's samples had a higher concentration of particulates than did the standard cottons of the same grade.