EP1375361A1 - Corrugated board provided with a tear line - Google Patents

Abstract

The corrugated cardboard has a single corrugated layer (14) between two cover sheets (12a, 12b). These have tear lines (18) passing through at least 50% of their thickness, the corrugated layer being uncut or only cut at the peaks of the corrugations.

Description

The invention relates to corrugated cardboard in a single-shaft design with corrugated paper, which is connected on both sides with two cover papers and has a tear line along which the Corrugated cardboard is tearable, taking the two cover papers along the tear line are cut on both sides.

Corrugated cardboard is used as a material for many transportation, moving and in recently also increasingly used for sales packaging. In addition to transport protection, many of these packages are used made further demands. One of them is that the packaging is simple, reliable, safe and light can be opened. For this purpose, conventional corrugated cardboards Perforations or similar combinations of cuts along the Tear line on. Some of these perforations are through supports a taped tear thread made of tear-resistant material, which should make the opening more reliable.

From DE 197 05 533 an arrangement for the formation of a Tear line for solid and compact cardboard known, in which the Cardboard on both sides by a distance of a few millimeters has staggered scratches. When tearing the tears Cardboard in the paper plane between the floors of the scratches. However, this process is not transferable to corrugated cardboard, since there is no homogeneous material.

GB 777,079 discloses a single-wall corrugated cardboard with tear lines, alternatively, continuous cuts made in the ceiling papers are only cut (i.e. the ceiling papers do not cut completely) or an interrupted one Perforation, however, the ceiling papers completely cuts, proposed. In any case, they are mutually spaced tear lines, so that an untidy tear edge arises when tearing open.

DE 693 00 351 T2 discloses a tear-open device for Corrugated cardboard in which a tear tape is provided, and Lines of weakness on both sides of the tear tape and opposite them more on the back cover paper Lines of weakness are provided. Such a construction has some major drawbacks. That's the construction structurally complex, and there can be no round or arcuate Tear lines run because of the tear tape plastic is glued to the cardboard blank. In addition, the freedom of design is subject to the arrangement of the tear line due to it Straightforwardness significant restrictions.

The known tear-open systems could meet the requirements an easy-to-open, but fully stable Packaging does not meet. The main reason is technical contradiction between the weakening on the one hand the material of the corrugated cardboard for the opening process and on the other hand maintaining the stability of the material for the Transport protection. The known systems all try one Find a compromise between these two diametrical requirements.

For example from the publication "Transport packaging Solid and corrugated cardboard "from the European Trade Institute (EHI) it follows from page 13 that the conventional systems all are unsatisfactory (not suitable). On page 30 of this publication from 1998 it follows that boxes with Perforations have to be opened time consuming and that Personnel are tempted to use knives at risk. Furthermore, the use of knives often leads to one unwanted extraordinary damage to the packaged goods.

The object of the present invention is therefore the tear line to form a generic corrugated cardboard in such a way that simple manufacture without the use of a tear tape is possible, the corrugated cardboard at the intended opening areas is easy and reliable to open without that the required stability of the corrugated cardboard is essential is impaired and clean, form smooth tear edges.

In other words, the invention aims to maintain stability the corrugated cardboard to ensure high efficiency Packing processes and securing the packaged goods during the Transportes serve, on the other hand, easily and reliably defined positions, namely the specified tear line, can be opened and this should above all clean edges opening to prevent cuts and Ensure optimal optics. The look is particularly important for display and sales packages, in which from the corrugated cardboard containers for receiving goods are manufactured, which are on store shelves, for example from Supermarkets.

The object is solved by the features of claim 1.

Advantageous further developments of the invention result from the subclaims.

The fact that in the invention only the ceiling papers are cut across from each other while the Wave structure not or only slightly (along the wave crests or troughs) is the mechanical one The stability of the corrugated cardboard hardly affected. At the Tear process, the cut ceiling papers look like Knife edges that keep the corrugated paper clean and non-cutting cut through the designated areas using the shear cutting method, resulting in clean and visually appealing cut edges leads. Thereby the corrugated paper is between the top cover paper one side and the bottom cover paper the other side intersected.

In other words, the invention serves to maintain stability corrugated cardboard to ensure high efficiency during packaging processes and securing the packaged goods during transport, on the other hand, it is light and reliable at defined points, namely the specified tear line, to open and this ensures above all clean Edges after opening to prevent cuts and to ensure optimal optics. The look is particularly important for display and sales packages, in which from the corrugated cardboard containers for receiving goods are manufactured, which are on store shelves, for example from Supermarkets.

It is advantageous if the ceiling papers are cut 100% become. With a lower cutting depth in the ceiling papers or if the opposite one is offset laterally Cuts in the ceiling papers larger than 1.5 mm is the special function of the effect of the tear edges as Sheared edges are not guaranteed, which usually leads to unclean Leading edges.

According to the invention, the depth of cut can be selected that the cut doesn't just complete the ceiling papers severed but also slightly penetrates the corrugated paper, so this is slightly along the wave crests are incised. The depth of cut should not exceed 5% of the distance between the two cover papers, a significant weakening of mechanical stability to avoid. When we talk about "wave paper", it is single or multi-layer paper.

Alternatively, it is also possible to choose the depth of cut, that the cut does not completely cover the ceiling papers, but cuts more than 50%, preferably more than 80%, while the wave paper is not cut. at this training is the cutting effect according to the invention not as good as with completely cut ceiling papers and therefore the tear edges are not correspondingly smooth. Therefore the strength of the corrugated cardboard in the area of the cuts is somewhat better than with deeper cuts, especially those that penetrate into the corrugated paper.

The cuts are preferably in the two cover papers directly opposite each other with respect to the plane of the corrugated cardboard. A lateral offset of up to 1.5 mm, better of less than 0.5 mm between the opposite cuts of the front and reach the back to a limited extent the beneficial effects of the invention. With a larger one lateral offset no longer has a cutting effect, rather, the corrugated paper is then only torn, which is too visual unsightly tear edges.

The results according to the invention are most optimal if the tear line is approximately perpendicular to the direction of the wave runs. In this context, under "wave direction" understood the direction in which the corrugated paper is straight runs. The smaller the angle between the tear line and wave direction, the stronger the fiber direction of the corrugated paper negatively affects the optics of the separating edge out.

According to an advantageous development of the invention this by a greater depth of cut and thus an increased Cutting the wave crests balanced, if the Angle between tear line and shaft direction is larger, in particular is more than about 30 degrees. By doing this tear lines with curves are not a problem, and it will possible complex curved tear-open mechanisms for production sales-effective display and sales packaging, as mentioned for example in DE 197 05 533, reliably in Implement corrugated cardboard. Compared to that described in EP 571 197 B1 Procedure with taped tear tape the invention is characterized by the advantage that displays with rising side walls or higher rear walls can be realized.

At an even smaller angle between the tear line and Wave direction of preferably less than 30 degrees is according to an advantageous development, the cutting line wave-like trained, either by a wave-like Cut or by using knives with serrated edge, which keeps the cutting depth within profitable limits can.

The greater the depth of cut and thus the cutting of the Corrugated paper, the lower the relative effort when tearing open the corrugated cardboard. This effort decreases disproportionately with increasing depth of cut, while the relative weakening of stiffness to the same extent increases disproportionately, as the Disproportionate length of the cut paper decreases, but especially for the rigidity of the corrugated cardboard important areas of the wave structure with large The angle of attack is only cut at a large depth of cut become. It follows that with a slight incision the stability of corrugated cardboard relatively little subsides, but the corrugated cardboard is much easier to tear open is.

The longer fiber the ceiling paper compared to the corrugated paper the easier it is to tear open the corrugated cardboard. On the other hand, the stiffness with the tear line decreases provided corrugated cardboard relatively least if that Corrugated paper is more fibrous than the ceiling paper.

Figur 1:

Eine schematische perspektivische Darstellung einer erfindungsgemäßen Wellpappe beim Schneidevorgang;

Figur 2:

den Schneidevorgang gemäß Figur 1 in schematischer Seitenansicht;

Figur 3:

eine Schnittdarstellung der Wellpappe mit teilweise eingeschnittenem Wellenpapier;

Figur 4:

die Wellpappe beim Aufreißvorgang;

Figur 5:

drei Varianten von Einschnitten in eine Wellpappe;

Figur 6:

eine beispielhafte Anwendung der Wellpappe für einen ersten Verpackungskarton;

Figur 7:

eine beispielhafte Anwendung der Erfindung für einen zweiten Verpackungskarton.

The invention is explained in more detail below on the basis of preferred exemplary embodiments and the accompanying drawings:

Figure 1:

A schematic perspective view of a corrugated cardboard according to the invention during the cutting process;

Figure 2:

the cutting process according to Figure 1 in a schematic side view;

Figure 3:

a sectional view of the corrugated cardboard with partially cut corrugated paper;

Figure 4:

the corrugated cardboard during the tearing process;

Figure 5:

three variants of cuts in corrugated cardboard;

Figure 6:

an exemplary application of the corrugated cardboard for a first packaging box;

Figure 7:

an exemplary application of the invention for a second packaging box.

1 shows a corrugated cardboard 10 in perspective, which consists of an upper cover paper 12a and a lower cover paper 12b and a corrugated paper 14 arranged between them and glued to both cover papers 12a, 12b . The corrugated paper 14 is rectilinear in the direction of the corrugation 16 and corrugated perpendicular to it. As shown in FIG. 1 , the tear line 18, along which the corrugated cardboard is to be torn open later, is formed by cutting through the cover papers 12a, 12b by means of two knives 20a, 20b , the two cuts being one above the other with respect to the corrugated cardboard plane, i.e. none have lateral offset to each other.

As can be seen from FIGS. 2a and 2b , the knives 20a, 20b can either only cut through the cover papers without affecting the corrugated paper 14 (FIG. 2a ), or the corrugated paper 14 is also scored in the region of the crests 22 (Fig. 2b).

FIG. 3 shows an enlarged view of the extent to which the corrugated paper 14 is scored according to the invention. The depth of cut 24 on each side is preferably not more than 5% of the distance between the two cover papers 12a, 12b, that is to say the thickness of the corrugated cardboard 10. Along the cut lines, the corrugated paper 14 is therefore only present in fragments, but this is not a significant reduction in the case of small depths of cut which causes rigidity and strength.

In Figure 4 , the tearing process is shown schematically in perspective. The corrugated cardboard 10 is torn open along the tear line 18, which is at the same time the cut into the top cover paper 12a , the tear edges thereby formed also functioning as shear edges 26a, 26b , which ensures a clean and smooth separation of the corrugated paper 14 . This function is ensured in particular if the two ceiling papers 12a, 12b are completely cut through. Otherwise, no sharp-edged shear edges can form if the ceiling papers themselves have to be torn through in part.

To illustrate the invention, FIG. 5 shows three cut variants in a corrugated cardboard 10 , the thicknesses of the two cover papers 12a, 12b being shown enlarged in relation to the extent of the corrugated paper 14 for the sake of illustration. The first cuts 40a, 40b cut through the ceiling papers 12a, 12b 100% without significantly penetrating the corrugated paper 14 . About 60% of the second cuts 42a, 42b penetrate the cover papers 12a, 12b , the corrugated paper 14 is not cut. The third cuts 44a, 44b cut through the cover papers 12a, 12b completely, the corrugated paper 14 is cut to about 10% (the distance a between the cover papers 12a, 12b ). The third cuts 44a, 44b also have a lateral offset b, which is less than 1.5 mm.

6 shows an exemplary application of the invention for a corrugated box 28 (so-called "American case") in perspective, the corrugation direction 16 of the corrugated cardboard being shown (the direction of the arrow or the lines). This corrugated box 28 comprises a tear tab 30 , which is formed by the circumferential tear line 18 . As a result, the tear line 18 can be designed in such a way that the tear tab 30 can be removed without the aid of knives etc., leaving clean and smooth tear edges. In the area in which the tear line 18 runs parallel to the shaft direction 16 , a wave-like curved tear line 32 can also be used instead of the straight one. At angles between 0 ° and 90 °, the depth of cut can be greater than in those areas in which the tear line 18 runs perpendicular to the shaft direction 16 .

FIG. 7 shows another exemplary application of the invention for an outer packaging carton 50 , in which the direction of corrugation of the corrugated paper is represented by the arrows w. The almost arbitrarily shaped cutting line 52 , which can run in a straight line or an arc, is shown in FIG.

In the event that the cutting line runs parallel to the wave direction w (shown in dashed lines), a wave-like (reciprocating) cutting line 54 can be expedient in order to achieve an average weakening of the wave structure, while in the case of a straight cutting line depending on the wave structure a very large or no weakening of the corrugated paper is possible in the cutting line.

Claims (8)

Corrugated cardboard in a single-corrugated version with corrugated paper (14) which is connected on both sides to two cover papers (12a, 12b) and has a tear line (18) along which the corrugated cardboard (10) can be torn open, the two cover papers (12a, 12b) along of the tear line (18) are cut in on both sides, characterized in that the cuts in the two cover papers (12a, 12b) cut through these at least 50%, while the corrugated paper (14) is not cut at all or only in the area of the crests, and the Cuts in the two cover papers (12a, 12b) lie opposite each other and the tear line (18) is straight or arched. Corrugated cardboard according to claim 1, characterized in that the cuts in the two cover papers (12a, 12b) lie directly opposite one another. Corrugated cardboard according to claim 1, characterized in that the cuts in the two cover papers (12a, 12b) have a lateral offset of not more than 1.5 mm. Corrugated cardboard according to claim 1, characterized in that cuts in the two cover papers (12a, 12b) cut them 80% - 100%. Corrugated cardboard according to claim 1, characterized in that at an angle between the tear line (18) and the corrugation direction (16) of more than 70 °, the cover papers (12a, 12b) are completely cut through and the mutual cutting depth in the corrugated paper (14) up to 5 % of the distance between the two cover papers (12a, 12b) is. Corrugated cardboard according to claim 1, characterized in that, at an angle between the tear line (18) and the corrugation direction (16) of 30 ° and 70 °, the mutual depth of cut in the corrugated paper (14) up to 10% of the distance between the two cover papers (12a, 12b). Corrugated cardboard according to claim 1, characterized in that at an angle between the tear line (18) and the shaft direction (16) of more than 75 °, the cutting lines are curved in a wave-like manner. Corrugated cardboard according to one of claims 1 to 7, characterized in that the tear line (18) consists of several line sections with different angles between the tear line and the direction of the corrugation and, depending on the angle size, different cutting depths and cutting line shapes are provided.

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