The thickness (4W) of the side seals (4) of the pants type disposable diaper of this creation than constitute its veutro portion (F) and drosal part (R) each the part in addition to the side seals (4) thickness it is big. The veutro portion (F) and drosal part (R) system for constituting side seals (4) separately include the lamination construction of plurality of sheet-like component and constitute, and the fusing point of the composition fiber of at least one flat member and the fusing point of composition fiber of other flat members are different in a plurality of flat members. The above-mentioned lamination of veutro portion (F) and drosal part (R) construction separately includes low melting point innermost layer type lamination construction (41), and low melting point innermost layer type lamination construction (41) is that innermost layer includes the low melting point flat member that above-mentioned fusing point is minimum in a plurality of above-mentioned flat members. Side seals (4) system is formed by laser sealing means.本創作之褲型拋棄式尿布之側密封部(4)之厚度(4W)比構成其之腹側部(F)及背側部(R)各者之除該側密封部(4)以外之部分之厚度大。構成側密封部(4)之腹側部(F)及背側部(R)係分別包含複數個片狀構件之積層構造而構成，複數個該片狀構件中至少一個片狀構件之構成纖維之熔點與其他片狀構件之構成纖維之熔點不同。腹側部(F)及背側部(R)之上述積層構造分別包含低熔點最內層型積層構造(41)，該低熔點最內層型積層構造(41)係最內層包含複數個上述片狀構件中上述熔點最低之低熔點片狀構件。側密封部(4)係藉由雷射密封方式而形成。
