Packaging materials and bags

[Abstract] A packaging bag (1) in which the heat sealing parts of the packaging materials (2, 3) having a printed light shielding layer (14) in a layered structure are overlapped and heat-sealed, and When the heat sealing members are fitted together, a sealing state confirming portion (8) having a light transmittance higher than that of the other sealing side is provided on a sealing side (11) of the two mutually facing sealing sides. Therefore, visual confirmation of the incompletely heat sealed part can be performed.
[Summary Items] 1. A packaging material comprising a light shielding layer formed by printing in a layered structure and a plurality of positions to be heat-sealed and heat-sealed with each other in a manufacturing package, one for A sealed state confirming portion is provided at a position that is heat-sealed and heat-sealed with each other, and the light transmittance of the heat-sealed state confirming portion is higher than those of other heat-sealed positions of the packaging material.