A bag making apparatus and a bag making method make bags. The bag has a first panel part and a first flap part formed by folding a first sheet part, and a second panel part and a second flap part formed by folding a second sheet part. The first and second panel parts face each other. The first and second flap parts are interposed between the first and second panel parts and face each other. An open edge is formed by folded edges of the first and second sheet parts. The bag further comprises adhesive located between the open edge and the engagement tool, interposed between the first and second flap parts and extending across the widths of the first and second sheet parts to peelably adhere the first and second flap parts to each other. Alternatively, the second sheet part may only consists of the second panel part.

A packaging bag has a bag body formed from a flat web and has a first front wall and a second front wall as well as a stand-up bottom formed in a bottom section by folding and gluing the front walls. The flat web has a varnish coating on an outside of the bag body, wherein the first front wall has an adhesive region free of the varnish coating in the bottom section of the bag body.

The bag may include a draw tape that may be used to cinch closed the opening of the bag. The draw tape has at least one stretched elastomeric strip attached to the draw tape in an extended condition. The draw tape may be smaller in size than the bag sidewalls. The draw tape may include an elastic characteristic, such as patterned ribs. In one embodiment, the roll of bag is kept under tension to maintain the elastomeric strips in a stretched condition.

Disclosed is a sealed bag and a processing method thereof, the method including presetting a folding baseline on a base paper piece, and performing a first plastic sealing on a gap between an overlapping area of the second folding portion and the first folding portion so as to form a paper roll; supporting the paper roll so as to perform side pressing on the paper roll so that the paper roll is embedded to form a first closing and a third folding line, wherein the area between the first folding line and the first side pressing line serves as a bottom surface of the first closing, and the area between the first side pressing line and the third folding line serves as a top surface of the first closing; plastically sealing the bottom opening of the fully pressed paper roll to form a finished sealed bag.

Disclosed is a sealed bag and a processing method thereof, the method including presetting a folding baseline on a base paper piece, and performing a first plastic sealing on a gap between an overlapping area of the second folding portion and the first folding portion so as to form a paper roll; supporting the paper roll so as to perform side pressing on the paper roll so that the paper roll is embedded to form a first closing and a third folding line, wherein the area between the first folding line and the first side pressing line serves as a bottom surface of the first closing, and the area between the first side pressing line and the third folding line serves as a top surface of the first closing; plastically sealing the bottom opening of the fully pressed paper roll to form a finished sealed bag.