Abstract
Interlaboratory check tests show excellent correlation between our homemade air-per meability instrument and both the University of Tennessee's "Arealometer" and an air-per meability instrument in another laboratory. From similar results reported by other investigators for their own instruments, it is concluded that any instrument of this type if properly calibrated can do a good job of measuring surface area.†
Comparison of data found in the literature on normal fiber perimeter, wall thickness, sur face area, and weight per inch with calculated values indicates that all laboratory measurements of fiber dimensions are surprisingly accurate and consistent. Drawings of fiber cross sections with various combinations of dimensions indicate that fibers with the same surface area are most alike in appearance and ought to be more alike in their spinning behavior than those selected for uniformity by any other fineness measurement. A chart is given (Figure 5) from which any two of the four fineness variables can be read if the other two are known.
It is. shown that fibers of the same surface area may vary widely in weight per inch, and that no conversion from surface area to weight per inch can be accurate unless one other variable is held constant. This may be either wall thickness, fiber diameter, or their ratio, usually called "maturity."
Get full access to this article
View all access options for this article.