Provided is a carbon dioxide generating sheet exhibiting excellent persistency in generating carbon dioxide. This carbon dioxide generating sheet is a laminate having a carbonate layer and an acid layer, the carbon dioxide generating sheet being characterized in that a water-permeable or water-absorbent sheet is provided between the carbonate layer and the acid layer, and the carbonate layer and the acid layer are obtained by disposing a mixture of carbonate particles or acid particles and a heat fusible resin on the surface of the water-permeable or water-absorbent sheet and then thermally fusing the heat fusible resin. Furthermore, this carbon dioxide generating sheet is a laminate having a carbonate layer and an acid layer, the carbon dioxide generating sheet being characterized in that the carbonate layer and the acid layer are provided adjacent to each other, and at least one of the carbonate layer or the acid layer includes a water-absorbent material.本發明提供產生二氧化碳之持續效果優越的產生二氧化碳之片材。本發明為一種產生二氧化碳之片材，係具備碳酸鹽層及酸層之積層體，其特徵為，於上述碳酸鹽層與上述酸層之間具備透水性或吸水性片材，上述碳酸鹽層及上述酸層係於上述透水性或吸水性片材之表面配置碳酸鹽粒子或酸粒子與熱融著性樹脂的混合物並藉由熱使上述熱融著性樹脂熔融而獲得者。本發明並提供一種產生二氧化碳之片材，係具備碳酸鹽層及酸層之積層體，其特徵為，上述碳酸鹽層及上述酸層係鄰接設置，上述碳酸鹽層及上述酸層中之至少一者為含有吸水性材料之層。
