We examined how the selection of skin barriers in proportion to the drainage was obtained for clinical use. Digestive juice was carried in 9 kinds of prototypes,taking the development of skin barriers with high buffer action into consideration,and pH was measured on a time-dependent basis. Ten grams of the main raw material of skin barriers was stirred in distilled water and digestine juice until it was dissolved,and the pH was measured. When the SIS (styrene-isoprene-styrene block copolymer) consists of 25％ or less,the SIS rate in the hydrophobic polymer gives to skin barriers an excellent buffer action. However,it is necessary to consider the constituents of the prototype,to consider that the buffer action for gastric juice is weak,and that it can not be used in a gastric fistula. Although karaya gum,which is the main raw material of skin barriers,is excellent for buffer action in alkaline environment,mixtures of CMC are necessary when buffer action in an acidic environment is necessary.

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　For the development of skin barriers with high buffer action,we examined water absorption,waterproof properties,peeling force and change of time-dependent pH values in 9 prototypes. Because weight variation after 96 hours is based on a fixed room condition,the compounding ratio of the hydrophilic polymer rises,and water absorption is greater. It was proven that mixtures of the SIS （styreneisoprene-styrene block copolymer） were necessary in order to base the area rate on the water immersion,and also in the results of waterproof properties for the normal shape. Peeling force by prototype pasting took considerable time,and there were many instances of increasing stickiness after 48 hours. The adhesive power of PIB （polyisobutylene） was inhibited by the SIS,because adhesive power was strong in case not including the SIS,and because the peeling force was high. From the time-dependent pH value of the skin surface,the buffer action was strongly demonstrated in the skin barriers in which the SIS was not included and in which there was a high amount of a hydrophilic polymer.

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