Four commercial water repellent fabrics were washed five and ten times and subsequently ironed at 160°C. After the treatments, water and oil repellencies were measured according to the JISL 1092-92 5.2 and AATCC 118 respectively. The water repellency was lowered by the washing and recovered by the ironing. Furthermore, a change of the surface characteristics by washing and ironing was investigated by means of ESCA analysis. The F_1Sintensity was decreased by washing and increased by the subsequent ironing. On the other hand, the O_1Sintensity was increased by washing and decreased by ironing. From these results, it is clear that change of the water repellency of the water repellent fabric by washing and subsequent ironing is greatly related to the change of the surface chemical composition. It has been considered that the f luoroalkyl groups rotate from surface to inside by washing and inside to surface by ironing. Whereas we wonder if rigid fluorocarbon resin treated on the fiber surface is evidently difficult to rotate into the fiber by washing and subsequently to surface by the heat treatment. Therefore, we have assumed that recovery of the water repellency by the ironing is caused by elimination of very small quantity of water cluster deposited on the fiber surface after washing.

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An attempt has been made to find out the difference of visial assessments by using various specimens. As many colour fastness formulae, i.e., ISO, Ns and Fs, have been proposed, we have attempted to know the relationship between visual assessments and instrumental assessments. In this study, we have suggested the comparison between visual and instrumental assessments through colour fastness contours in a colour space. In order to derive a proper colour fastness formula for assessing staining, we have also analyzed the relationship between a new colour depth value and visual assessments.
As a result, we have found out the followings:
1. The variation in visual assessment is inevitable.
2. The assessment values according ISO, Ns and Fs depend on the value of the hue. The tendency of its dependency is especially remarkable in the yellow area.
3. A relationship between visual and instrumental assessment have been found by the medium of colour fastness contours.
4. A formula based on colour depth might be more proper for the application to assess stain-ing as a distance in a colour space.

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