PROBLEM TO BE SOLVED: To prevent degradation of heating characteristics of a heating layer of a laminated heating element, while suppressing degradation of bonding strength between a first base material sheet and a second base material sheet.SOLUTION: There is provided a manufacturing method of a laminated heating element 1A in which a heating layer 3 is arranged between a first base material sheet 2A and a second base material sheet 2B. Any one of the first and second base material sheets 2A, 2B includes a heat fusible fiber. The manufacturing method of the laminated heating element 1A comprises: a coating step of coating the first base material with an exothermic composition 3b so that non-coating areas 2b1, 2b2, 2b3 is formed on the surface of the first base material sheet 2A an overlapping step of obtaining a laminated heating intermediate 2C by overlapping the second base material sheet 2B so that the heating layer 3 is covered on the surface of the first base material sheet 2A and the second base material sheet 2B is arranged on the non-coating areas 2b1, 2b2, 2b3 of the first base material sheet 2A and a bonding fusion cutting step of performing bonding and fusion cutting at the same time with ultrasonic wave along the non-coating areas 2b1, 2b2, 2b3 of the laminated heating intermediate 2C.SELECTED DRAWING: Figure 2COPYRIGHT: (C)2018,JPO&INPIT【課題】第1基材シートと第2基材シートとの接合強度の低下を抑えつつ、該積層発熱体の有する発熱層の発熱特性の低下を抑制すること。【解決手段】第1基材シート2Aと第2基材シート2Bとの間に発熱層3が配された積層発熱体1Aの製造方法である。第1及び第2基材シート2A,2Bの何れか一方は熱融着繊維を含んで形成されている。積層発熱体1Aの製造方法は、第1基材シート2Aの表面に未塗工領域2b1,2b2,2b3が形成されるように発熱組成物3bを塗工する塗工工程と、第1基材シート2Aの表面に発熱層3を覆い、かつ第1基材シート2Aの未塗工領域2b1,2b2,2b3上に第2基材シート2Bが配されるように第2基材シート2Bを重ね合せて積層発熱中間体2Cを得る重ね合せ工程と、積層発熱中間体2Cの未塗工領域2b1,2b2,2b3に沿って超音波により接合と同時に溶断する接合溶断工程とを備える。【選択図】図2
