Side-gusset bag and method of making same

Abstract

A side-gusset bag has front and back face panels each having two longitudinally extending side edges. Two folded side panels are each joined to the face panels at the side edges and each having a center longitudinally extending crease between the respective side edges. A handle assembly consists of a pair of substantially identical handle halves each formed by two longitudinally spaced ends fixed to one of the side folds to a respective side of the crease thereof and a middle section extending between the respective ends and formed unitarily therewith of plastic film. The middle sections are transversely spaced and form an open longitudinally extending gap at least 2 mm wide and aligned with the respective crease. The middle sections extend transversely over less than 80% of a transverse width of the one side fold and have outer edges space at least 5 mm from the respective side edges.

Claims

1. A side-gusset bag comprising: front and back face panels each having longitudinally extending side edges; two folded side panels each joined to the face panels at the side edges and each having a center longitudinally extending crease between the respective side edges and subdividing the respective side panel into a pair of side folds; and a handle assembly extending transversely over less than 80% of a transverse width of one of the side panels, having outer edges spaced at least 5 mm from the respective side edges, and consisting of a pair of substantially identical handle halves each formed by two longitudinally spaced ends fixed to a respective side fold on an outer face of the respective side fold of the bag to a respective side of the crease thereof and a middle section extending flat and without folds on the respective side panel between the respective ends and formed unitarily therewith of plastic film, the middle sections being transversely spaced by a longitudinally extending gap at least 2 mm wide and aligned with the respective crease, the handle halves being hidden in the one side panel in a flattened condition of the bag.

2. The side-gusset bag defined in claim 1, wherein the outer edges of the handle assembly are spaced at least 15 mm from the two respective side edges.

3. The side-gusset bag defined in claim 1, wherein the bag is formed as a prefabricated flattened package that is sealed at one longitudinal end and unsealed at the opposite longitudinal end for subsequent filling.

4. The side-gusset bag defined in claim 1, wherein the handle halves are with mirror symmetrical to each other at the crease.

5. The side-gusset bag defined in claim 1, wherein the gap is straight over its entire length and has a uniform width that is at least 5 mm.

6. The side-gusset bag defined in claim 1, wherein each of the ends of the handle halves is transversely wider than the respective middle section and projects therefrom away from the respective crease.

7. The side-gusset bag defined in claim 1, wherein the two handle halves are connected to each other exclusively via the one folded side panel.

8. The side-gusset bag defined in claim 1, further comprising: an application film extending between the halves across the gap and having a width equal to at most one-third of a width of the film of the handle halves.

9. The side-gusset bag defined in claim 1, further comprising: adhesive fixing the ends of the handle halves to the one side panel.

10. The side-gusset bag defined in claim 1, wherein the film forming the handle has a thickness between 150 m and 400 m.

11. The side-gusset bag defined in claim 1, wherein the face panels and the folded side panels are each formed from a multilayered plastic film that can be welded on the inner side of the bag.

12. The side-gusset bag defined in claim 1, wherein the face panels or the folded side panels have a layer made of a plastic woven fabric.

13. The side-gusset bag defined in claim 1, wherein the folded side panels are longitudinally shorter than the face panels.

14. The side-gusset bag defined in claim 1, further comprising: longitudinal welds at the side edges.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

(2) FIG. 1 is a perspective view of a side-gusset bag with a handle assembly on one of the folded side panels;

(3) FIG. 2 is a side view of a detail of the handle assembly on the one folded side panel;

(4) FIG. 3 is a section through the flattened side-gusset bag in the region of the folded side panel shown in FIG. 2 along line of FIG. 2;

(5) FIG. 4 shows an alternative design of the side-gusset bag in a view like FIG. 3; and

(6) FIG. 5 shows a possible method step for mounting a handle assembly on a film web.

SPECIFIC DESCRIPTION OF THE INVENTION

(7) As seen in FIG. 1 a filled and tightly sealed side-gusset bag is preferably produced first as a prefabricated unfilled side-gusset bag and then subsequently filled and sealed. The side-gusset bag comprises two opposite face panels 1 and two folded side panels 2a, 2b that are each joined to the face panels 1 at side edges 3 and connect the face panels 1 to each other.

(8) In the center between the respective side edges 3, the folded side panels 2a, 2b each have a straight crease 4 running in a bag longitudinal direction 1, a handle assembly 5 having a film handle being attached to one of the folded side panels 2a on an outer side of the bag. According to the invention, provision is made that the handle assembly 5 is interrupted at the crease 4 by a gap S with a width b.sub.Sp of at least 2 mm and running in the longitudinal direction 1 that separates the film handle into a pair of handle halves.

(9) FIG. 2 shows a detailed view of the handle assembly 5 on the folded side panel 2a. It can be seen here that the handle assembly has a width b.sub.T in a transverse direction q that is less than 60% of the width b.sub.Sf of the folded side panel 2a, the spacing a between the handle assembly 5 and the adjacent side edges 3 each also being at least 15 mm. The width b.sub.Sp of the gap S is usually between 2 mm and 20 mm, preferably between 5 mm and 15 mm, for example about 10 mm.

(10) FIG. 2 shows by hatching that the handle assembly 5 comprises two symmetrically identical handle halves each comprising a center section 6a or 6b and two ends 7a and 7b, with the ends 7a, 7b being longitudinally spaced and the sections 6a, 6b bridging the respective ends 7a, 7b. Together the sections 6a and 6b form a handle loop 8.

(11) The handle assembly 5 is preferably attached at the handle ends 7a, 7b with adhesive 9 (see FIG. 3) to the outside of the respective folded side panel 2a, whereas the middle sections 6a, 6b forming the loop 8 are unattached, so that a user can grip behind the handle loop 8 formed by the two middle sections 6a 6b if his/her hand is inserted between the respective folded side panel 2a and the film handle sections 6a, 6b.

(12) The two film handle sections 6a, 6b thus form a single handle loop 8 for the user, the gap S advantageously being dimensioned such that a user can easily grip behind the two film handle sections 6a, 6b at the handle loop 8 during handling, but the folded side panel 2a can also easily be folded at the crease 4 without the handle assembly 5 being in the way and interfering. In addition, a substantial spacing a of at least 15 mm from the side edges 3 also remains, so that folds and/or longitudinal welds 10 can also be formed there without problems during the manufacture of the side-gusset bag.

(13) The handle assembly 5 is usually mounted on the bag film section forming the folded side panel 2a before the folded side panel 2a is shaped into a bag body either by folding of the bag film or by joining of several pieces of the bag film. Independently of whether the folded side panels 2a, 2b are supplied as separate film strips or formed from a material web, the required manufacturing process is not substantially impaired by the handle assembly 5 according to the invention, because both the crease 4 and the side edges 3 remain clear. Since the film handle itself does not need to be folded, there is also no substantial spreading effect at the respective first folded side panel 2a.

(14) As can be seen in FIG. 2, the two film handle sections 6a, 6b are usually arranged with mirror symmetry at the crease 4, the gap S running straight over its entire length and having the same width b.sub.Sp.

(15) To ensure secure attachment of the film handle sections 6a, 6b to the respective folded side panel 2a, the handle assembly 5 can have be widened in the transverse direction q at the handle ends 7a, 7b with respect to the handle loop 8, so that the two film handle sections 6a, 6b then have a C-shape starting from the gap S in the direction of the respective adjacent side edge 3.

(16) FIG. 3 shows a section through the folded side panel 2a provided with the handle assembly 5 in a mostly flattened state, the section passing through the handle ends 7, so that the adhesive 9 is also visible there. According to FIG. 3, the two face panels 1 are connected to the folded side panel 2a only via the longitudinal welds 10. Such a connection results if the face panels 1 and the folded side panels 2a, 2b are supplied as separate pieces of a bag film or if the side edges 3 are subsequently edged by folding and welding during manufacture of the folded side panel, that is, if outer edges on the side edges 3 are trimmed away in order to improve the appearance.

(17) According to the embodiment of FIGS. 1 to 3, the two film handle sections 6a, 6b are interconnected exclusively via the underlying folded side panel 2a.

(18) FIG. 4 shows an alternative embodiment in which the two film handle sections 6a, 6b are connected by a thin application film 11. The application film facilitates handling of the handle assembly 5 during manufacture, it then being possible to manipulate the handle assembly 5 like a conventional, continuous one-piece handle. The application film 11 is so thin, however, that it does not bring about any substantial spreading effect.

(19) The thickness ratio of the film handle to the application film 11 is usually at least 3:1. While the film handle usually has a thickness between 150 m and 400 m, preferably between 200 m and 300 m, the application film can be comparatively thin, for example with a thickness of less than 100 m, particularly less than 50 m.

(20) During handling, the carrying forces are substantially absorbed by the two film handle sections 6a, 6b, the gap S between the two film handle sections 6a, 6b still being present but being covered toward the outside by the application film 11.

(21) In principle, the application film 11 can also be between the film handle sections 6a, 6b and the corresponding folded side panel 2a, in which case the handle assembly 5 is then attached via the application film 7. If an additional application film 11 is provided, it bridges over the gap S but preferably also has the same shape as the two film handle sections 6a, 6b, which can result in the appearance of a single handle for the observer.

(22) As already explained above, the handle assembly is usually mounted before the side-gusset bag is put together from various pieces or formed by folding. The two film handle sections 6a, 6b of a handle assembly 5 can be fed either completely independently from each other or connected to an application film. In this context, FIG. 5 shows a variant of the manufacturing method in which the film handle sections 6a, 6b for several successive side-gusset bags are arranged on an application film 11 that is then removed again after the mounting of the film handle sections 6a, 6b onto a film web. FIG. 5 shows a material web from which the face panels 1 and the folded side panels 2a, 2b are then formed subsequently by folding. The side edges and center lines 4 that are not yet present in the material web, are indicated for purposes of orientation.