If polyester fibers are treated in a solution of caustic soda, they dissolve successively form their outer surface, accompanied by the changes in the properties of the fabrics made of them. This experiment determines the equilibrium amount of disperse dyes absorbed in polyester films treated with caustic soda solutions under various conditions. An uptake of the dyes on films treated with an alkaline solution has been discussed in relation to the changes of a molecular structure of films. The following results were obtained:
(1) Under the mild condition of alkaline hydrolysis, the films dissolved uniformly from their outer surface with very few changes in their physical structures. Under the severe condition, however, the films changed their physical structures owing to an OH^- attacked to the inner regions. These results agreed considerably with the change of the density of films.
(2) The tensile strength of films treated with alkaline solution decreased as the percentage of weight loss caused by the hydrolysis increased. The loss of tensile strength was much remarkable at the lower percentage of weight loss. These phenomena were related to the fact that films increased their density, i. e., degree of cristallinity, by the hydrolysis.
(3) As the percentage of weight loss of films increased, the uptake of the dyes increased. This phenomenon well coincided with the increase of the amount of voids.
(4) The decrease of the depth of shade of polyester fabrics treated with alkaline solution is explained by the irregular light reflection from the irregular surface of fibers occured by alkaline hydrolysis. (Received February 12, 1980)

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A survey of 1600 young womens in the Western Japan was made to investigate the degree of consumrs'requirement of 55 questionaire items on five kinds of women's garments for the summer. The data have been analyzed and following results were obtained:
(1) The CV% is suitable to express the variation of the degree of consumers' end-use requrement. The lower CV% means that the degree of requirements coincide well among pollees, showing that the result is highly reliable.
(2) The CV% is affected by the shape of a frequency histogram of the degree of end-use requirement. When the CV% is more than 40%, two peaks appear in a histogram, suggesting that the degree of the requirement is abnormal.
(3) The significantly high negative correlation has been noticed between the degree of end-use requirement and the value of CV%. The greater the degree of requirement, the less the value of CV%.
It means that the consumer's requirement coincide well among pollees.
(4) The averages of CV% ofthe aesthetic appeal, specific function and comfort of T-shirt and summer sweater are more than 30%.

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The results of the survey described in Part 1 are discussed by classifying into two different categories. Each degree of end-use requirements of five kinds of clothings has been discussed. The main results obtained are as follows
(1) As a whole, the degree of end-use requirements of the quality and performance of safety and practical use are high. However, those of appearance and comfort are low.
(2) The degree of end-use requirements of outer wears are higher than those of intermediate and underwears. Moreover, the difference among degrees of end-use requirement of outer wears is much samller.
(3) Comparing the results obtained in the study to the preliminary survey carried out by the Japan Research Association for Textile End-Uses, the degree of end-use requirement of this survey is, as a whole, higher than those of the preliminary survey.
(4) To make results of the survey concise, the degrees of end-use requirements have been classified by codes into four groups.

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