Abstract: As a support for an external patch, a laminated sheet having a laminate structure of two or three layers in which a secondary sheet made of hydrophobic fibers is laminated on one side or both sides of a main sheet made of hydrophilic fibers is used.

Abstract: The present invention has an object to provide a novel external patch packaging structure which suppresses leakage of a chemical solution at the time of opening a bag material. In an external patch packaging structure obtained by enclosing an external patch in which a support is impregnated with a chemical solution in a bag material, as the bag material, one closed by a heat seal band provided at a periphery is used, the heat seal band includes: an easy-peel seal portion; and a strong seal portion having a higher seal strength than the easy-peel seal portion, and when the easy-peel seal portion is peeled off and the bag material is opened, the strong seal portion restricts a peeling area of the heat seal band, and thus a liquid storage pocket is formed inside the bag material.