Flat-bottomed gusseted bag made from multi-layer sheet

Patent metadata

Field	Value
Publication number	US-9963272-B2
Application number	US-201213721809-A
Country	US
Kind code	B2
Filing date	Dec 20, 2012
Priority date	Dec 20, 2012
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

A flat-bottomed bag is formed from a flexible sheet that initially is flat prior to being manipulated to form the bag. The sheet is a laminate of a first web and a second web laminated together by an adhesive layer disposed between the webs. The sheet defines a plurality of serially connected side wall panels collectively defining a vertically extending side wall of the bag, and a plurality of bottom panels respectively connected to the side wall panels at respective fold lines. The bottom panels are folded about the fold lines and are attached together to form a flat bottom wall configured to support the bag in an upright orientation. The adhesive layer is in a partial-coverage pattern that includes adhesive-free regions located along each fold line between each bottom panel and the respective side wall panel connected therewith.

First claim

What is claimed is:

1. A flat-bottomed bag, comprising:
a blank comprising a flexible sheet, the sheet comprising a laminate of a first web and at least a second web, a face of the first web being affixed to an opposing face of the second web by an adhesive layer disposed between the first and second webs, the blank defining:
a front panel;
a left side panel joined to a left side edge of the front panel;
a right side panel joined to a right side edge of the front panel;
either a single rear panel joined to one of the left or right side panels, or a pair of partial rear panels respectively joined to each of the left and right side panels;
a plurality of bottom panels respectively joined to lower edges of the front, left side, right side, and rear panels; and
fold lines respectively formed at each juncture between said panels;

the blank forming a bag with each joined pair of panels disposed generally perpendicular to each other, a leftmost edge of the blank being attached to a rightmost edge of the blank along a longitudinal seam therebetween, the bottom panels being attached together to form a bottom wall of the bag;
wherein the adhesive layer is in a partial-coverage pattern that consists essentially of:
adhesive substantially covering the surface area of the side panels and bottom panels between the first and second webs;
discrete adhesive-free regions straddling respective fold lines between a corresponding bottom panel and the respective front, left side, right side, or rear panel joined therewith, such that each adhesive-free region extends along and at least some distance above and below the respective fold line, and such that areas of the blank in the adhesive-free regions have a lower stiffness than areas of the blank in which the first and second webs are affixed together by the adhesive.

2. A flat-bottomed bag for sitting upright on a surface, comprising:
a blank comprising a flexible sheet that initially is flat prior to being manipulated to form the bag, the sheet comprising a laminate of a first web and at least a second web, a face of the first web being affixed to an opposing face of the second web by an adhesive layer disposed between the first and second webs, the blank defining:
a plurality of serially connected side wall panels collectively defining a vertically extending side wall of the bag; and
a plurality of bottom panels respectively connected to the side wall panels, each bottom panel being connected to a respective one of the side wall panels at a fold line, the bottom panels being folded about the fold lines to extend generally perpendicular relative to the side wall panels and being attached together to form a flat bottom wall configured to support the bag in an upright orientation;
wherein the adhesive layer is in a partial-coverage pattern that includes
discrete adhesive-free regions straddling each respective fold line between a corresponding bottom panel and the respective side wall panel connected therewith, such that each adhesive-free region extends at least some distance above and below the respective fold line, and, such that areas of the blank in the adhesive-free regions along the fold lines have a lower stiffness than areas of the blank in which the first and second webs are affixed together by the adhesive;
continuous adhesive substantially covering the surface area of the side panels and bottom panels between the first and second webs in all areas other than the adhesive-free regions.

3. The flat-bottomed bag of claim 2 , wherein the bag is configured to be folded into a collapsed generally flat state when empty, and then to be erected into an opened state for filling with product and sealing.

4. The flat-bottomed bag of claim 2 , wherein the first web is formed principally of a first polymer material, and the second web is formed principally of a second polymer material.

5. The flat-bottomed bag of claim 4 , wherein the first and second polymer materials are chemically different.

6. The flat-bottomed bag of claim 2 , further comprising a closure feature formed in the side wall of the bag.

7. The flat-bottomed bag of claim 6 , wherein the closure feature comprises a flap formed in the side wall by a generally U-shaped score line that extends through the thickness of the first web, which forms an outer surface of the bag, but does not extend through the second web, which forms an inner surface of the bag, such that the flap can be peeled away from the second web without breaching the bag.

8. The flat-bottomed bag of claim 7 , wherein the laminate includes a pressure-sensitive adhesive between the first and second webs in the area of the flap, such that the flap when peeled away from the second web has the pressure-sensitive adhesive on the flap, whereby the flap can be re-adhered to a rolled-down top end of the bag to hold the top end in the rolled-down configuration so as to reclose the bag after initial opening.

9. A flat-bottomed bag for sitting upright on a surface, comprising:
a blank comprising a flexible sheet that initially is flat prior to being manipulated to form the bag, the sheet comprising a laminate of a first web and at least a second web, a face of the first web being affixed to an opposing face of the second web by an adhesive layer disposed between the first and second webs, the blank defining:
a plurality of serially connected side wall panels collectively defining a vertically extending side wall of the bag; and
a plurality of bottom panels respectively connected to the side wall panels, each bottom panel being connected to a respective one of the side wall panels at a fold line, the bottom panels being folded about the fold lines to extend generally perpendicular relative to the side wall panels and being attached together to form a flat bottom wall configured to support the bag in an upright orientation;
a closure feature formed in the side wall of the bag, wherein the closure feature comprises at least one flap formed in the first web such that the at least one flap can be peeled away from the second web without breaching the side wall of the bag;
wherein the adhesive layer is in a partial-coverage pattern that includes:
at least one pressure-sensitive adhesive region on the interior surface of the at least one flap whereby the at least one flap can be re-adhered to a rolled-down top end of the bag to hold the top end in the rolled-down configuration so as to reclose the bag after initial opening;
discrete adhesive-free regions straddling each respective fold line between a corresponding bottom panel and the respective side wall panel connected therewith, such that each adhesive-free region extends at least some distance above and below the respective fold line, and, such that areas of the blank in the adhesive-free regions along the fold lines have a lower stiffness than areas of the blank in which the first and second webs are affixed together by the adhesive;
optionally, at least one adhesive-free region corresponding to at least one tab portion of the flap; and
permanent adhesive substantially covering the surface area of the side panels and bottom panels between the first and second web in all areas other than the pressure-sensitive adhesive regions and adhesive-free regions.

10. The bag of claim 9 wherein permanent adhesive is disposed between each adhesive-free fold region in the connection location of each side wall.

11. The bag of claim 9 wherein the adhesive-free fold regions are generally rectangular in shape.

12. The bag of claim 9 wherein the adhesive-free fold regions are generally centered about the respective fold line.

13. The bag of claim 9 where

Assignees

• Sonoco Dev Inc

Inventors

• Trollen Jonathan Edward

Classifications

• B65D65/40

  Applications of laminates for particular packaging purposes {(B65D1/0215, B65D1/28, B65D3/22, B65D5/0281, B65D5/563, B65D9/30, B65D29/02, B65D31/02, B65D75/26, B65D77/2024, B65D81/1275, B65D81/3811, B65D81/3823, B65D81/3834, B65D81/3846, B65D81/3858, B65D81/3874, B65D81/3886, B65D81/3897 take precedence; laminates per se or laminated packages characterised by the composition or)} · CPC title

• B65D31/08

  with block bottoms · CPC title

• B65D75/008

  Standing pouches, i.e. "Standbeutel" · CPC title

• B65D33/16

  End- or aperture-closing arrangements or devices (valves of valve bags {B65D31/14}; closures of filled bags B65D77/10) · CPC title

• B65D33/20

  using pressure-sensitive adhesive · CPC title