JPH05215B2 - - Google Patents

Abstract

To facilitate butt-welding, or L- or T-weld joints the edges of a plastics-coated paper-layered web (1) of packaging material is thickened e.g. by folding over and sealing down edge zones. The folding line (14) of each edge zone may be creased before folding, and the upstanding crease enclosed between the folded edge zone and the body of the web. The sealing of the edge zone may be effected by pressure rollers (21) holding the edge zones against a rotating cylindrical surface (22), whereby a curl or curvature is imposed upon the web.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to packaging materials and packaging containers formed therefrom.

Although the packaging material of the present invention is used in the production of packaging containers of known shapes and its use will be described, it must be understood that the packaging material described herein is not limited to that use only.

[Conventional technology]

Packaging containers of the known shapes described above are manufactured by joining two web materials together.
That is, the first web has a series of deep grooves extending transversely through the web and defined by upright folded walls of the web, which are formed by an endless molding chain. has.
The second web has edge bands providing side flaps. The central part of the second web that does not form the side flaps rests on the upper edge of the partition wall of the first web and is joined, and the side flaps are folded downward and rest on the edges of the grooves of the first web. Heat sealed to form a chain of interconnected closed containers that can be separated from each other.

[Problem to be solved by the invention]

Previously, the above-mentioned known containers were constructed from a web of foamed plastic material having a homogeneous plastic outer covering suitable for heat sealing. However,
The use of such materials makes these containers too expensive for some intended uses. The main object of the present invention is to make an even cheaper version of the above-mentioned known containers and to provide a packaging laminate of inexpensive materials suitable for other packaging purposes.

[Means to solve problems]

The packaging container of the present invention consists of two parts formed from a thin, flexible packaging material with a heat-sealable surface, the two parts having a portion of the edge of one part that is connected to the other part. In packaging containers that are butt welded as an L or T weld to the surface, the edges of the parts that are butt welded as an L or T weld are formed by a narrow edge band of the material. is thickened by folding and bonding to an inner region of said material, thereby forming a folded edge surface that is widened to a thickness of more than twice the thickness of said packaging material; It is also characterized by providing a strong L-shaped weld or T-shaped weld with other parts.

A method of making a packaging container of the present invention includes molding a first web of thin, flexible packaging material having a heat-sealable surface to form a continuous trough in the transverse direction of said web; having a heat sealable surface to the trough of the web, being thin, flexible, and having a flap;
In a first method of manufacturing a packaging container, the second web of packaging material is sealed and the flaps are folded over and attached to the edge of the trough to form a plurality of continuous, interconnected closed containers.
Before shaping the web into a trough, the edges of the first web are thickened by folding the narrow edge bands on each side of the first web into contact with the interior adjacent areas of the first web. and join these areas together, thus making the thickness of the folded edge surface more than twice the thickness of the first web, and then applying the thickened edge surface as an L-shaped weld or a T-shaped weld. It is characterized by being joined to the second web.

The packaging container manufacturing apparatus of the present invention is an apparatus for manufacturing a web of packaging material having a thickened edge, and for a thin, flexible web of packaging material having a heat-sealable surface. Along two lines parallel to the edge and spaced apart,
roller means for imprinting grooves on one side and corresponding ridges on the opposite side, and automatically folding the edge band of the web formed by said grooves as the web advances, thus means for causing the ridges to be located between the folded areas of the web; and means for heat sealing the folded edge band to an adjacent web surface to reduce the thickness of the folded web to two times the thickness of the web. It is characterized by comprising means for making the thickness more than twice as thick.

[Example] A preferred embodiment of the present invention will be described with reference to the accompanying drawings.

As mentioned above, the packaging material according to the invention can be used to manufacture containers of known shapes, which shapes can be seen by reference to FIGS. 1 and 2 of the accompanying drawings. The lower web 1 of packaging material is formed by a mold into double-fold spaced upright walls 2 delimiting between laterally extending valleys or grooves in the web. The second upper web has a central longitudinal section 3 of substantially the same width as the upper edge of the wall 2 of the lower web;
a flap 4 extending from the longitudinal section 3 and having dimensions substantially corresponding to the end cross-section of the groove between the walls 2 of the lower web;
has. These two webs extend as shown in the figure, with the longitudinal section 3 resting on the line of the wall 2, the longitudinal section 3 being joined to the upper line of the wall 2, and the flap 4 being folded against the bottom edge of the groove. and is joined to this. The enclosures thus formed are filled with contents and separated from each other. Details of this packaging embodiment are described in British Patent No. 1332628, from which Figure 1 is incorporated herein.

An example of means for forming the web 1 shown in FIG. 1 is shown in FIG. A series of molding units 5 connected by joints to form an endless chain form continuous molding grooves between adjacent units,
A rotatable roller bank 6 forces the flat web 1 into these grooves, where the web engages the molding chain to leave a trough therebetween, as substantially shown in FIG. An upright transverse double-fold wall is created with. however,
It should be noted that in FIG. 2 the lower portion of each trough is substantially semi-cylindrical rather than square. A machine with such a molding chain is disclosed in British Patent Specification No. 1487693, from which FIG. 2 is incorporated herein.

As mentioned above, the web 1, the longitudinal sections 3 and the flaps 4 shown in FIGS. 1 and 2 are conventionally formed of a foamed plastic material (e.g. polyethylene or polystyrene), with a homogeneous plastic (e.g. similar plastic material) on each side. It had a coating layer. However, such materials make the product undesirable and expensive for some purposes. To overcome this difficulty, the present invention seeks to replace at least each of the webs 1 with inexpensive plastic-coated paper. The problem arising from such a substitution is that it is difficult to firmly seal the folded flap 4 of the upper web against the edge of the channel-shaped lower web 1 of the plastic-coated paper. To solve this problem, the present invention thickens the edges of the plastic-covered paper web 1 to provide a heat-sealable plastic surface.
A preferred method of achieving the above objects is also illustrated in Figures 3-14 of the accompanying drawings.

3, 4 and 5, the web 1, which has a plastic coating on both sides, is fed into the device via guide rollers 7. In FIGS. The type of paper used is known as "duplex" paper, which has bleached fibers on one side (the outer surface of the carton formed from the web) and unbleached fibers on the other side. Each side of the paper web is coated with a plastic film (eg polyethylene).

The rollers 7 are provided with a pair of rollers 9, which are provided with flanges 8 to prevent lateral displacement of the advancing web and are held by adjustable pressure spring means.
10 upper rollers 9. roller 9
After having passed around a part of the web, the web passes through a hold-down between flanged rollers 9, 10 for its positioning.

Close to each flange, but slightly apart, the roller 9 is provided with a peripheral groove 12 (shown in FIG. 5 by partially removing the flange). Corresponding to the grooves 12, the roller 10 is provided with cooperating upright ribs or ridges 13.

As the web runs between the rollers 9, 10, the ribs and grooves cooperate to stamp grooves 14 into the web slightly spaced from each edge. A cross-section of the cooperative rollers 9, 10 carrying out this operation is shown in FIG. 6, and a cross-section of the grooved web is shown in FIG. Protruding pleats on the opposite side of the web are shown in these figures.

A feature of the invention is that on the outside of the grooves 14 on both edges of the web a narrow edge band is folded and sealed towards the center of the web. For this purpose, the web is passed through heating means 15 to soften the plastic coating of the web so as to be foldable, and then through folding means 15a the edge band is folded inwards.

Convenient forms of heating means are shown in FIGS. 8, 9 and 10. The U-shaped heating means (tube) 15 is provided with a hot air inlet 16 at its center point. heating tube 15
The side arms of the heater are substantially parallel and the width of the heater substantially corresponds to the width of the web. The heaters are positioned so that they are on opposite edges of the web that travels beneath the heaters in a direction parallel to the axis of the side arm. Holes or grooves 17 are provided in the underside of the side arms through which hot air is blown against the edges of the advancing web to soften the plastic coating for sealing. The heater, shown in perspective view in FIG. 8, is shown in cross section in FIG.
A side view of the side arm is shown in FIG.

After being heated, the web passes through a folding device. A preferred form of this device is shown in Figures 11a and b. For example, a rigid plate 18 made of metal may be substantially flat at the end where the web first makes contact, but on one side of the longitudinal centerline of the plate, one half of the plate is twisted relative to the other half of the plate; Thus, as shown in Figure 11-b, as one progresses along the plate from one flat end to the other, the twisted half 19 of the plate gradually increases its inclination with respect to the other half 20 until it finally becomes at right angles. It then forms an acute angle with respect to the other half 20 and finally folds parallel to the other half but slightly apart.

As the web reaches this folding plate and slides along it, it approaches the outer edge of plate section 19, and as it advances further, the edge band of the web is gradually folded and folded back by the twisted part of the plate until finally At the opposite end of the plate it is folded flat against the inner surface of the web. The successive stages of this folding operation are illustrated in Figure 11-b by cross-sections of the plate at various points along its length. In order to reduce the friction of the web against the folding plate, the plate can also be equipped with rollers, a frame or a row of rollers. Folding devices are provided at both edges of the web.

The surface of the web that is heated is the surface that is to be the outer surface of the container made from the web, and therefore the plastic coating of the web surface that is to be the inner surface of the container extends around the folded web as a result of folding and is narrow. Appears on the other web surface as an edge band.

Edge grooves 14 in the web created by rollers 9, 10 cause pleats (FIG. 7) to project therefrom and run on the folding board substantially along the center line of the board. As a result of the folding of the edge band, the pleats are directed inwardly between the web and the folded edge band, as shown in FIG.

To complete the production of the web, the folded and heated edge band is pressed into contact and sealed with the web by roller means. During the process of forming the container (Figure 2), it may become curved.
The web can have a spiral or curved surface on the surface of the web that is to be the inside surface of the container. This effect was achieved by pressing the web against a rotating cylindrical surface when sealing the folded edge band.

In FIGS. 3 and 13, a pressure roller 21 running under the edge of each folded web presses the edge of the web against a cylinder 22 provided with a flange 23 to prevent sideways shifting of the web. The diameter of cylinder 22 is selected according to the degree of twist or curvature desired in the finished web. Pressure roller 21 seals the folded edge band to the body of the web with appropriate pressure. The edge of the pressure roller 21 adjacent to the folded edge, thickened by folding and inward facing pleats (FIG. 12), is rounded to prevent flattening of this thickened, plastic-faced edge. Or beveled. The finished web is drawn off and rolled into a roll for subsequent feeding to a packaging machine.

〔Effect of the invention〕

When the web of packaging material according to the present invention as described above is formed into a horizontal groove shape using a die as shown in FIG. 2 in the process described with reference to FIGS. 1 and 2 of the accompanying drawings. It is convenient to use it for the lower web 1. It will be appreciated that the twists or curvatures imparted to the web by the rotating cylinder 22 under counterpressure are to assist in forming the web by the mold shown in FIG. The upper webs 3, 4 (FIG. 1) for use with the web material according to the invention may be of the conventionally used type (e.g. a foamed plastic material with a plastic-coated surface) or may be made of the material according to the invention. . In each case, the thickened edge of the lower web 1 is attached to the flap of the upper web by a butt weld or an L-weld or a T-weld. The heat sealable plastic surface of the thickened edge of the lower web must be made of the same plastic coating material as that of the upper web to which it is to be joined.

[Brief explanation of drawings]

FIG. 1 shows the manner in which a container of the above-mentioned known form is manufactured; FIG. 2 shows a part of the known machine used for manufacturing the known container; FIG. 4 is a plan view of the roller shown in FIG. 3; FIG. and a partially cutaway perspective view of the pair of rollers shown in FIG. Figure 8 shows a perspective view of a heating device for heating the edge band of the material before folding; Figures 9 and 10 show the heater shown in Figure 8; 11 is a folding device suitable for folding edge bands of material;
Figure -a is a partially cutaway perspective view, Figure 11-b
The figures show end views of the device in successive stages of the folding operation; figure 12 is an enlarged cross-sectional view of the pleats shown in figure 7 after folding; figure 13 shows the folded edge band in the inner part of the material. An end view of the sealing roller for sealing; and FIG. 14 is an enlarged cross-sectional view of the edge of the finishing material provided with an edge having a thickened plastic coating by folding and sealing. 1... Web, 7... Guide roller, 8...
Flange, 9, 10...roller, 12...groove, 13...ridge, 15...heating means, 15a...
...Folding means, 16...Duct, 18...Hard plate, 19...Twisted part of 18, 20...1
The flat part of 8.

Claims (1)

Claims: 1. Consisting of two parts formed from a thin, flexible packaging material with heat-sealable surfaces, the two parts having a portion of the edge of one part of the other part. L-shaped weld or T to the surface
In packaging containers that are butt welded as L-shaped welds or T-shaped welds, the edges of the parts that are butt welded as L-shaped or T-shaped welds bend a narrow edge band of the material and is thickened by bonding to the area, thereby forming a folded edge surface extending to a thickness of more than twice the thickness of the packaging material, thus forming a strong L with other parts. A packaging container characterized in that it provides a shaped weld or a T-shaped weld. 2. A first web 1 of thin, flexible packaging material having a heat-sealable surface is molded to form a continuous trough transversely to said web, and the troughs of the first web are subjected to heat treatment. Thin, flexible, with a sealable surface
and by sealing the second webs 3, 4 of packaging material with flaps 4, and further by folding down said flaps 4 and attaching them to the edge of said trough, a plurality of successive, interconnected closed containers are formed. In a method for manufacturing a packaging container to form a trough, the edges of the first web are thickened by folding the narrow edge bands on each side of the first web before the first web is molded into a trough. , in contact with the inner adjacent region of the first web, joining these regions together, such that the thickness of the folded edge surface is equal to the thickness of the first web.
A method for manufacturing a packaging container, characterized in that the thickness is made more than twice the thickness of the web, and then the thickened edge surface is joined to a second web by L-shaped welding or T-shaped welding. 3 Apparatus for producing a web of packaging material with a thickened edge, said web 1 of packaging material having a heat-sealable surface, parallel to and spaced apart from both edges of the web. Along the two open lines,
roller means 9, 10 for carving grooves on one side and corresponding ridges on the opposite side; automatically folding the edge band of the web formed by said grooves as the web advances; means 19, 20 for ensuring that each said ridge is located between folded areas of the web, and heat sealing the folded edge band to the adjacent web surface to reduce the thickness of the folded web. An apparatus characterized by comprising means for making the thickness of the web more than twice the thickness of the web.