Envelopes with Flood-Coated Bonding Element

The present application is a divisional application of U.S. patent application Ser. No. 18/660,171, filed May 9, 2024, which claims priority of U.S. Patent Application No. 63/501,116, filed May 9, 2023, and U.S. Patent Application No. 63/518,199, filed Aug. 8, 2023, which are incorporated herein by reference in their entirety.

The present disclosure relates generally to packaging, such as envelopes, for holding items during, for example, shipping.

The use of shipping envelopes formed from paper has been growing in popularity in relation to poly bags, i.e., bags made of plastics such as polyethylene and polystyrene, due to the recyclability of paper. Poly bags typically are sealed closed after being loaded, by a heat seal formed by heating portions of opposing walls of the bag so that the wall portions fuse together. Sealing a paper envelope, by contrast, typically requires a separate bonding element in the form of an adhesive material deposited on one or both of the interior surfaces of the opposing walls.

In some applications, individual envelopes may be formed from a pre-formed web using automated equipment that also seals the envelope and separates the sealed envelope from the rest of the web after the envelope has been loaded. In such applications, the length of the envelope, i.e., the dimension of the envelope in the direction in which the envelope is advanced through the automated equipment, is set by the relative locations of the bonding elements on the interior surface or surfaces of the web. Thus, changing the length of the envelopes produced by the automated equipment requires that the web be changed-out to another web specifically tailored to the desired length of the envelopes to be produced.

In one aspect of the disclosed technology, an envelope for holding an item includes a first flexible wall, and a second flexible wall overlying the first flexible wall and affixed to the first flexible wall about at least a portion of a pocket border. The pocket border encloses a pocket defined at least in part by the first and second flexible walls, and is configured and dimensioned to contain the item. As least one of the first and second flexible walls defines a pocket opening allowing access to the pocket from an exterior of the envelope for loading the item into the pocket. The second wall is affixed to an adjacent portion of the envelope by at least a first seal. The envelope also includes a bonding element covering a majority of a surface of at least one of the first and second flexible walls. The the first seal is formed from the bonding element.

In another aspect of the disclosed technology, the bonding element includes a heat-activatable material.

In another aspect of the disclosed technology, the heat-activatable material includes a heat-sealable material.

In another aspect of the disclosed technology, the heat-activatable material includes a hot melt adhesive.

In another aspect of the disclosed technology, the first seal extends in a lengthwise direction of the envelope.

In another aspect of the disclosed technology, the second wall is further affixed to the first wall by a second seal extending in a direction generally transverse to the lengthwise direction of the envelope, the second seal being formed from the bonding element.

In another aspect of the disclosed technology, the second wall is further affixed to the first wall by a third seal extending in a direction generally transverse to the lengthwise direction of the envelope, the third seal being formed from the bonding element, and the second and third seals define at least a portion of the pocket border.

In another aspect of the disclosed technology, a system for forming an envelope includes the above web stock, and a bagging machine having a sealing device configured to locally heat the web stock to form, from the bonding element, the second seal and the third seal.

In another aspect of the disclosed technology, the first seal extends along a first side edge portion of the envelope, and the second and third seals extend between the first seal and a second side edge portion of the envelope.

In another aspect of the disclosed technology, the bonding element covers a substantial entirety of the surface of at least one of the first and second flexible walls.

In another aspect of the disclosed technology, the bonding element covers at least about 85 percent of the surface of at least one of the first and second flexible walls.

In another aspect of the disclosed technology, the bonding element covers at least about 90 percent of the surface of at least one of the first and second flexible walls.

In another aspect of the disclosed technology, the bonding element covers at least about 95 percent of the surface of the first and second flexible walls.

In another aspect of the disclosed technology, the bonding element covers at least about 100 percent of the surface of the first and second flexible walls.

In another aspect of the disclosed technology, the first and second walls includes paper.

In another aspect of the disclosed technology, the first, second, and third seals are formed from activated portions of the heat-activatable material.

In another aspect of the disclosed technology, a portion of the heat-activatable material is not activated.

In another aspect of the disclosed technology, a system for forming an envelope includes the above web stock, and a bagging machine having a sealing device configured to locally heat the web stock to form, from the bonding element, the second seal and the third seal.

In another aspect of the disclosed technology, a method for forming a envelope configured to hold an item to be packaged includes providing a web stock having a first wall, a second wall overlying the first wall and affixed to the first flexible wall about at least a portion of a pocket border that encloses a pocket defined between the first and second walls and configured to contain the item, and a bonding element covering a majority of a surface of at least one of the first and second walls. The bonding element forms a first seal extending in a generally lengthwise direction of the web stock. The method further includes forming, from the bonding element, a second seal and a third seal between the first and second walls. The at least the second and third seals form a portion of the pocket.

In another aspect of the disclosed technology, the second and third seals extend in a generally transverse direction of the web stock. The method further includes advancing the web stock in a lengthwise direction of the web stock by a first distance after forming the second seal and before forming the third seal, the first distance corresponding to a desired dimension of the envelope in a lengthwise direction of the envelope.

In another aspect of the disclosed technology, forming the second seal and the third seal includes forming the second seal and the third seal using a sealing device configured to apply heat to the web stock; and advancing the web stock in a lengthwise direction of the web stock by a first distance includes advancing the web stock to align a location on the web stock at which the third seal is to be formed with the sealing device.

In another aspect of the disclosed technology, the method further includes inserting the item to be packaged into the pocket after forming the second seal and before forming the third seal; and separating the envelope from the web stock by forming a line of separation through the third seal.

In another aspect of the disclosed technology, the envelope is a first envelope; and the method further includes advancing the web stock by a second distance after separating the envelope from the web stock, the second distance corresponding to a desired lengthwise dimension of a second envelope to be formed from the web stock.

In another aspect of the disclosed technology, the second distance is unequal to the first distance.

In another aspect of the disclosed technology, forming a third seal between the first and second walls includes forming the third seal at a location spaced from the second seal in the lengthwise direction of the web stock by a distance about equal to a desired dimension of the envelope in the lengthwise direction of the web stock.

In another aspect of the disclosed technology, the method further includes varying a spacing between the second and third seals to provide the envelope with a predetermined dimension in the lengthwise direction of the web stock.

In another aspect of the disclosed technology, advancing the web stock by a second distance after separating the envelope from the web stock includes advancing the web stock to align a location on the web stock at which a fourth seal is to be formed by the sealing device, and the method further includes forming the fourth seal in the generally transverse direction of the web stock using the sealing device.

In another aspect of the disclosed technology, the method further includes spacing the third seal from the second seal in the lengthwise direction of the web stock so that the pocket is dimensioned to hold the item.

In another aspect of the disclosed technology, forming a second seal between the first and second walls includes applying localized heat and pressure at a position on at least one of the first and second walls corresponding to a desired location of the second seal; and forming a third seal between the first and second walls includes applying localized heat and pressure at a position on at least one of the first and second walls corresponding to a desired location of the third seal.

In another aspect of the disclosed technology, the bonding element includes a heat-sealable material.

In another aspect of the disclosed technology, the bonding element includes a hot-melt adhesive.

In another aspect of the disclosed technology, the method further includes forming a pocket opening configured to allow access to the pocket from an exterior of the envelope for loading the item into the pocket.

In another aspect of the disclosed technology, the method further includes inserting the item into the pocket by way of the pocket opening.

In another aspect of the disclosed technology, forming a third seal between the first and second walls includes forming the third seal after inserting the item into the pocket.

In another aspect of the disclosed technology, the first seal extends along a first side edge portion of the web stock and fixes the first wall to the second wall; and the second and third seals extend between the first seal and a second side edge portion of the web stock.

In another aspect of the disclosed technology, the bonding element covers a substantial entirety of the surface of at least one of the first and second walls.

In another aspect of the disclosed technology, the bonding element covers at least about 85 percent of the surface of at least one of the first and second walls.

In another aspect of the disclosed technology, the bonding element covers at least about 90 percent of the surface of at least one of the first and second walls.

In another aspect of the disclosed technology, the bonding element covers at least about 95 percent of the surface of at least the one of the first and second walls.

In another aspect of the disclosed technology, the bonding element covers at least about 100 percent of the surface of at least the one of the first and second walls.

In another aspect of the disclosed technology, the first seal extends along a first side edge portion of the web stock, the web stock further includes a fourth seal formed from the bonding element and extending in a generally lengthwise direction of the web stock and along a second side edge portion of the web stock, and the fourth seal further affixes the first wall to the second wall.

In another aspect of the disclosed technology, the web stock includes paper.

In another aspect of the disclosed technology, providing a web stock includes providing a first and a second sheet of stock material, at least one of the first and second sheets having a surface coated with the bonding material over a majority thereof; aligning respective edges of the first and second sheets of stock material; bringing the first and second sheets of stock material into contact; and applying localized heat and pressure to at least one of the first and second sheets to form the first seal.

In another aspect of the disclosed technology, providing a web stock includes providing a sheet of stock material having a surface coated with the bonding material, folding the sheet about at least one fold line extending generally in the lengthwise direction of the web stock so that edge portions of the sheet overlap, and applying localized heat and pressure to the edge portions to form the first seal.

In another aspect of the disclosed technology, folding the sheet about at least one fold line extending generally in the lengthwise direction of the web stock so that edge portions of the sheet overlap includes folding the sheet about a first and a second fold line.

In another aspect of the disclosed technology, a system for forming an envelope includes a web stock having a first wall, a second wall overlying the first wall, and a bonding element covering a majority of a surface of at least one of the first and second walls. The bonding element forms a first seal extending in a generally lengthwise direction of the web stock. The system further includes a bagging machine having a sealing device configured to locally heat the web stock to form, from the bonding element, a second seal and a third seal between the first and second walls. The second and third seals form at least a portion of a pocket border that encloses a pocket defined between the first and second walls and configured to contain the item.