A soft film in dry state capable of absorbing moisture and a blood to form a hydrogel, wherein the film can be obtained by preparing a solid matter in the form of a film in a dry state from an aqueous solution of one of polyacrylic acid and polyvinyl pyrrolidone, bringing an aqueous solution of the remaining other into contact with the solid matter in the form of a film thus obtained, and thereafter drying the material.本發明為一種薄膜，其係可吸收水分或血液而形成水凝膠之柔軟而且在乾燥狀態的薄膜，並且可由聚丙烯酸或聚乙烯基吡咯烷酮之任一溶液調製出乾燥狀態的薄膜狀固體物，使所得到的該薄膜狀固體物和殘留之一者的溶液接觸之後進行乾燥所得到。
