FI85836B - Process for producing a packing wrapper - Google Patents

Description

85836

METHOD OF MANUFACTURING THE PACKAGING WRAP

The present invention relates to a method for producing a packaging wrapper, in which a wrapper formed of paper layers laminated to each other by means of a binder is produced as an elongate web.

A web-wide wide packaging wrapper is needed e.g. for packaging paper and cardboard boxes. On machines currently in use, the maximum width of the wrapper is usually of the order of 3.5 m.

Nowadays, there has been a need to produce paper as an even wider web, which means that the rolls of paper to be packaged are correspondingly even longer. An even wider packing wrapper is needed to package such rolls. The production of such a wrapper using conventional lamination techniques would require new machines that would require expensive investments. In addition, overcapacity would have to be built, as the need for special width packaging wrappers is limited, at least for the time being.

The prior art discloses FI publication 73264, which describes the lamination of a material web in such a way that an area is formed at the joint where the first web of materials overlaps from below. . ·. free baseline strip, solid laminator and second M * 1 ·· .. · material baseline free baseline strip. By heating with laminates -;! "· The substance causes the matter paths to adhere to each other and form- κ ..

· Ground seam. A disadvantage of said publication is that the solution requires heated sealing devices to melt the binder and is thus technically more cumbersome.

It is an object of the present invention to provide a solution with which; * .j an even wider packaging wrapper can be made without · *.} * · expensive equipment investment. The packaging wrapper according to the invention. The method of manufacturing 1 · * ree is characterized in that the webs ·! · * ·}: '.J are attached to each other by passing a molten binder, such as molten plastic, between their overlapping edges.

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Said staggering of the edges of the laminate webs can be achieved in the web-making step simply by the fact that one of the paper layers to be laminated on top of each other is slightly wider than the other. Otherwise, these doughs can be made by standard lamination techniques.

The most advantageous solution for fastening the doughs to each other is that a bonding agent, such as molten plastic, is passed between the overlapping edges of the fastening step. It would also be possible to place the binder between the edges of the webs in solid form, e.g. as a strip parallel to the seam to be formed, but this solution would require heated sealing means to melt the binder and would thus be technically more cumbersome. The same applies to the solution that the binder is ready in the stepped edge areas of the webs to be fastened together.

An adhesive which is the same material as the binder used to laminate the paper layers of the webs can be advantageously used to attach the webs. The result is a wide compound 1 in the form of a web in which a uniform binder layer of the material composition binds the overlapping paper layers together.

Suitable binders for the process according to the invention are ld-polyethylene, hd-polyethylene and polypropylene. However, other so-called extrusion head1 foams can come into question · ......

The invention will now be described in more detail, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows the conduction of molten plastic as a binder: .2-.1 between the stepped edges of 1 amine 11 to be joined together; Fig. 2 shows the joint of the expanded packaging wrapper web obtained from the doughs of Fig. 1 after joining, Fig. 3 shows a side view of a process for manufacturing an expanded packaging wrapper according to the invention, and Fig. 4 shows a process of making an expanded packaging wrapper according to Fig. 3. process seen from above.

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According to the invention, the web-shaped packaging wrapper is made of two separate laminate webs 1, 2, each of which consists of two paper layers 3, 4 and an adhesive layer 5 between them, as shown in Figure 1. The binder 5 can be an adhesive plastic such as Id or HD polyethylene or polypropylene. The webs 1, 2 are staggered at their opposite edges so that one of the overlapping paper layers 3 extends past the second layer 4 in the width direction of the web.

The joining of the laminate webs 1, 2 takes place according to Fig. 1 by guiding the stepped edges of the webs. . melt binder 6, which may be the same substance as

The binder 5 used in the doughs 5. The molten binder 6 can thus be, for example, Id or hd polyethylene, polypropylene or a similar extrusion coating plastic. After application of binder 6

The edges of the stakes 1, 2 are pressed against each other so that they overlap in staggered portions, whereby the binder '·· solidifies, resulting in a laminated expanded wrapping web 7 according to Fig. 2, the width of which is almost the same as that of the webs 1 , 2 combined width. The method can thus provide a joint of up to 6 m wide, with an overlapping seam area 8. the width is of the order of 10-20 cm.

Figures 3 and 4 show a process for the production of an expanded packaging wrapping web 7, in which the expanded web is formed by joining two narrower laminate webs 1, 2 according to the principle of Figures 1 and 2. The webs 1, 2 are guided from the rollers 9, 10 in parallel between the sealing rollers 11, 12, thus:; that their stepped edges according to Figure 1 face each other. A binder in the molten state is passed between the edges from the nozzle 13. The rollers 11, 12 press the webs 1, 2 together at their edges into a widened dough 7, which is guided on a roll 15 under the guidance of the roll 14. When the laminate webs 1, 2 have the same width, a seam area 8 is formed in the middle of the widened composite web 7.

4,85836

It will be clear to a person skilled in the art that the various embodiments of the invention are not limited to the examples presented but may vary within the scope of the appended claims.

Claims (3)

A method of producing a packaging wrap in which a wrapping of superposed paper layers (3, 4) which has been laminated together with the binder (5) is made as an elongated web, such that two separate laminate webs ( 1, 2) are formed, wherein both webs are differentiated at their other edge such that one of the paper layers (3) located on each other continues in the width direction of the web past the second layer (4), and these webs are guided in parallel. so that their differentiated edges are overlapped, and attached to said edges to each other as a wider web forming a finished wrap, characterized in that the webs (1, 2) are attached to each other by passing between their overlapping edges in a molten state existing binder (6), such as molten plastic. Method according to claim 1, characterized in that the webs (1, 2) are attached to each other by a binder (6), which may be of the same material as the binder (5), which is used for laminating paper layers (3, 4) of the webs (1, 2). Process according to claim 1 or 2, characterized in that as the binder (5, 6) Id or hd polyethylene or polypropylene is used. li