PROBLEM TO BE SOLVED: To provide a sheet agent in which only a backing layer of a support body can be easily peeled when being used.SOLUTION: Provided is a sheet agent that is housed in a packaging vessel. The sheet agent comprises laminating a support body (A) and a hydrous gel layer (B), and is that the support body (A) comprises laminating a backing layer that is composed of a polyvinyl alcohol copolymer in which a decay time in 5°C standing water by the following measuring method is at least 30 seconds, and a moisture hardly permeating layer, and the sheet agent is that the hydrous gel layer (B) comprises being laminated to an opposite side face of a face of the moisture hardly permeating layer in which the backing layer is disposed. (A measuring method of the decay time) (1) One end of a strip test piece of a specific dimension is fixed. (2) A portion in which a length is 30 mm from the other end of the strip test piece is immersed in the 5°C standing water to be retained. (3) That when being drawn up from the standing water, a portion immersed is lost by being dissolved in the standing water, or the portion immersed is torn from a non-immersion portion of the test piece right after being drawn up is made the decay, and the shortest immersion time in which the test piece is performed by [the decay] is made [the decay time].COPYRIGHT: (C)2014,JPO&INPIT【課題】使用時に支持体の裏打ち層のみを容易に剥がすことができるシート剤を提供する。【解決手段】包装容器内に収納されているシート剤であって、該シート剤は、支持体(A)と含水ゲル層(B)を積層してなり、支持体(A)が、下記測定方法による5℃静水中における崩壊時間が30秒以上であるポリビニルアルコール共重合体から構成される裏打ち層と、難透湿層を積層してなり、含水ゲル層(B)が、難透湿層の裏打ち層を設けた面と反対側の面に積層してなるシート剤。(崩壊時間の測定方法)(1)特定寸法の短冊試験片の片端を固定する。(2)短冊試験片の他端から長さ30mmまでの部分を、5℃静水中に浸漬し、保持する。(3)静水中から引き上げた時、浸漬した部分が静水中に溶解してなくなっているか、引き上げた直後に試験片の非浸漬部分から千切れて落下する場合を、「崩壊」とし、試験片が「崩壊」する最短の浸漬時間を「崩壊時間」とする。【選択図】なし
