In order to make the sewing procedure much easier, sewing threads are generally treated with various kinds of oiling agents. Oiling treatment of sewing thread sometimes affects the color of the threads. In this study, color changes in sewing threads made of polyester fibers by conventional launderings and dry cleanings were investigated on the basis of reflectance, K/S values, color difference, tristimulus values, dominant wavelength and excitation purity. The effect of laundering and dry cleaning on the color change of commercial sewing threads is remarkably different depending on the manufactures of the sewing thread. The colors of some threads were not changed by laundering but the apparent color depths were changed by the dry cleaning. Some were changed by both laundering and dry cleaning. As it is recognized that dyes are not removed from commercial sewing thread by the dry cleaning, it seemed that the color changes observed after laundering or dry cleaning were due to the refractive index of the oiling agents. Therefore, the selection of oiling agent must be considered not only from the view point of the lubricating effect but also from the color change.

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As a fundamental study on application of extracellular enzyme produced by animals and microorganisms to the removal of blood protein stains from fabrics, the influence of substrate specificity of protease and protease activity in a washing solution were studied using the fabrics soiled with bovine blood (whole blood, defibrinated blood, blood plasma and blood serum) .
The blood protein stains, which adhered to the fabrics in a state of coagulation with blood serum, denatured as the days left at room increased and gradually became insoluble, and as a result it became very difficult to remove the blood protein stains from fabrics compared with other water-soluble protein stains. However, when alkaline protease produced byBacillus subtilisin var. having a wide range of substrate specificity and neutral or alkaline protease produced byAspergillus oryzaecausing a decrease in viscosity of gelatin solution were used, the detergency of blood protein stains were remarkably high. Especially, the removal efficiency of blood serum protein stains which have low dissolubility or dispersive power into water increased more than 50-60% when the washing solution of protease activity over 25 PU/ml were used.
The fibrinogen contained in whole blood and blood plasma caused the decrease of solubility into water of these protein stains on the fabrics. And generally the removal efficiency of these blood protein stains containing fibrinogen decreased compared with that of stains without fibrinogen when protease was used.

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This peper aims to investigate the relationship between the drawing force of piles in towels and the number of launderings experimentally, and to improve the defect of the falling out of piles in towels.
The results obtained are as follows:
(1) The drawing force of towel pile increases with an increase of the number of launderings. The drawing force reaches a maximum value at forty times of launderings. Over forty times of launderings, the drawing force decreases gradually, because the pile yarns become thinner.
(2) The pile twist increases with an increase of the number of launderings. Pile fibers adhere each other by drying of service water, and then the towel becomes stiffer gradually.

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