Abstract: Provided is a microwavable pouch including an automatic steam venting mechanism, which includes a steam venting sealing portion, a slit, and a flap piece. The steam venting sealing portion includes a seal peeling start portion. The slit includes a pair of slit end portions and a slit intermediate portion formed toward a region closer to the seal peeling start portion than the pair of slit end portions, and the automatic steam venting mechanism further includes an unsealed portion formed to cover the entire periphery of the slit and a control sealing portion formed by heat-welding a part of the flap piece to a second film.

Abstract: Provided is a microwavable pouch having a rectangular outer shape in plan view. The microwavable punch includes an automatic steam release mechanism. The automatic steam release mechanism includes a steam release portion and a steam release seal portion surrounding the steam release portion, and assuming that there is an inscribed ellipse in contact with centers of inner edges of sides of a peripheral seal portion of the pouch, the steam release seal portion is formed so that a circumference of the inscribed ellipse is positioned in a width region of a seal separation start portion of the steam release seal portion closest to a center point of an accommodation portion or in a vicinity of the seal separation start portion.