A heat seal device for use in a bag making apparatus includes: a first heat seal member; a second heat seal member facing the first heat seal member; a heater for heating at least one of the first heat seal member or the second heat seal member; a drive mechanism configured to move the first heat seal member towards and away from the second heat seal member so as to releasably sandwich a web between the first and second heat seal members; a sensor disposed to detect acceleration of the first heat seal member; and a measurement part configured to measure a sandwiching time during which the web is sandwiched by the first and second heat seal members based on data from the sensor.

A method for manufacturing a rectangular-bottomed packaging bag includes an unfolding step of unfolding a flat bag by separating a pair of opening/closing plates (13) inserted into the flat bag from each other in a thickness direction of the flat bag, and a gusset forming step, after the unfolding step, of forming a side gusset and a bottom gusset by thrusting folding plates (11 and 12) between the pair of opening/closing plates (13) from the outside of the bag toward the inside of the bag.

During the manufacturing process the exterior surface of one or both of the sheets of plastic film which form the bags is treated with low temperature corona discharge plasma to raise the level of surface charge magnitude to at least 43 Dyne to increase the adhesion force between the bags. A recess is formed in each of the bags to further increase the adhesion. The increased adhesion causes the mouth of one bag to automatically open as the adjacent bag is removed from the rack. The recess is formed at the same time openings are created in the bags to accept the support rods of a dispensing rack. The bags can have simple edge sides or side gussets and may be provided in a package including a pouch which receives and supports the lower portions of the bags.

A packaging bag unsealed from a first side to a second side opposed to the first side, including: an inclination seal part (5) at a corner provided consecutively to the second side, wherein the inclination seal part (5) has a strong-pressure seal zone (7) along an inner edge (50) of the inclination seal part (5), the strong-pressure seal zone (7) being pressed by a higher pressing force than other parts of the inclination seal part (5), and being smaller in thickness than other parts of the inclination seal part (5). Also disclosed is a pressing member and a method for manufacturing the packaging bag.

Apparatus and method of manufacturing open-mouth bags, comprising a storage device with a supply of bag film, a control device for controlling, a conveying device for conveying the bag film and/or the bag body along a conveying path, a welding device with welding means for making a bottom seam in the bag film and a cutting device with a cutting means for separating a predetermined film length of the bag film to form the bag body of an open-mouth bag. The control device controls the conveying device so as to cause a relative motion of the bag body and the bag film and a distance between the bag body and the bag film is generated prior to making the bottom seam. The control device controls the conveying device and the welding means so that while welding the bottom seam the welding means extend at least up to the bottom end of the bag body.

An installation for producing bags from two-layer plastic film includes a film gripper for drawing the plastic film into a tool at a first station, and a rotary conveyor belt for conveying the film through a plurality of stations. The film gripper is designed to guide the plastic film through the first station to a second station.

A method for manufacturing a pouch-type packaging material includes: a first folding process; a first cutting process of cutting the top-side sheet material, a second sub-region, a first main region, and a first sub-region along a first cutting line that extends from a portion where the top-side sheet material and the second sub-region overlap to a portion closer toward a bottom side in a z direction beyond a first boundary line; a second folding process; a second cutting process of cutting the top-side sheet material, the first sub-region, the first main region, and a second main region along a second cutting line to form a top-side sheet from the top-side sheet material, where the second cutting line extends from a portion where the top-side sheet material and the first sub-region overlap to a portion closer toward the bottom side in the z direction beyond the second boundary line.

A thermoplastic bag includes raised rib-like elements that allow the thermoplastic bag to expand. The thermoplastic bag further includes side seals having rib-like elements that allow the side seals to expand. Additionally, in one or more implementations, the thermoplastic bag includes one or more of a material formulation, a density of raised rib-like elements, a height of raised rib-like elements, or land areas that provide the raised rib-like elements with a reduced rebound ratio.

First and second panel webs are superposed on each other and fed in their longitudinal direction. After a side gusset is temporarily fixed to the second panel web, the side gusset is divided by a dividing device to form a pair of open edges. The open edges are aligned with a line of weakness of the first panel web when the first and second panel webs are superposed on each other. The side gusset is temporarily sealed to the first and second panel webs by a temporary seal device to form temporary sealed sections. The first panel web is guided to be divided along its line of weakness and to be folded on the sides of its division edges. This guiding of the panel web and the temporary sealed sections cause the side gusset to be opened at the open edges to form open surfaces. An end face web is then disposed on the panel web to be superposed on folded parts of the panel web and the open surfaces of the side gusset.

Disclosed are embodiments of a volume control storage bag and methods of making same. The volume control storage bag may have first and second sidewalls, a double-locking closure mechanism with a first closure element extending along the first sidewall and a second closure element extending along the second sidewall, each closure element having a channel and an elongated member configured for interlocking with one another. A gusset is sealed along three sides of the first and second sidewalls, leaving an opening through the closure mechanism and defining an interior space having a specific volume. Corner seals may be formed at the corners of the first and second sidewalls, further reinforcing the double-locking closure mechanism for an airtight and hence waterproof seal. The volume control storage bag may be made of a food-grade polyethylene vinyl acetate blend, approximately 90% or less ethylene vinyl acetate and approximately 10% or less polyethylene.