Patent ID: 6932754

Claim:
A method for manufacturing an angulated bottom paper bag using a rotary type bag manufacturing machine, which feeds out material paper wound in a roll to fold the material paper, after handles are pasted to the material paper to form angulated bottom paper bags with handles, said method comprising: an incising process for forming lateral slits and letter-J-shaped nicks connected to the lateral slits on the fed material paper; a handle pasting process for forming handle pasting portions adjacent to the letter-J-shaped nicks; a reinforcing paper pasting process for pasting reinforcing papers for attaching the handles to the handle pasting portions; a material paper cut-off process for forming cut lines connected to the lateral slits to cut off the material paper in a lateral direction; a top edge folding process for pasting a top edge of the material paper thus cut off and then folding the same toward an inside thereof; a paper tube forming process after the top edge folding process, said paper tube forming process forming a paper tube by substantially double-folding the material paper with the reinforcing papers thus pasted; and a bottom folding process for folding a bottom of the paper tube; wherein said paper tube forming process is carried out after said top edge folding process, said top edge folding process being preceded by said material paper cut-off process; wherein said lateral slits are provided at four positions located in a straight line extending in a direction perpendicular to said feed direction of the material paper, while said letter-J-shaped nicks extend from a center of each lateral slit toward a direction orthogonal to each lateral slit; wherein said reinforcing paper is pasted adjacent to each of said letter-J-shaped nicks; wherein said cut lines are formed so as to be aligned with said lateral slits, extending perpendicularly to said feed direction so that the material paper wound in a roll is cut off therealong to thereby obtain separated material paper sheets, each of the separated material paper sheets having a predetermined length, provided with said handle.