Sealant sheet

A sealant sheet formed as a sheet, comprising an epoxy group-containing polysulfide having a disulfide structure and an epoxy group in its molecule,

• wherein the epoxy group-containing polysulfide is a reaction product of an epoxy compound having two or more epoxy groups in one molecule and a thiol group-containing polysulfide having a disulfide structure and a thiol group in one molecule,
• wherein the epoxy group-containing polysulfide is the reaction product of an epoxy compound having two or more epoxy groups in one molecule and a thiol group-containing polysulfide having a disulfide structure and a thiol group in one molecule, wherein the epoxy compound is a combination of bifunctional epoxy compound and polyfunctional epoxy compound,
• a ratio (epoxy/thiol ratio) of the total number of epoxy groups in the epoxy compound to the total number of thiol groups in the thiol group-containing polysulfide is 1.0 or higher and below 2.0, and
• the sealant sheet has a storage modulus of 0.005 MPa or greater and 0.8 MPa or less at 25° C.