NL1019685C1 - Envelope for posting letters, invoices, documents and similar has tear-off strip positioned entirely on the rear side of it and formed by two perforated runs limiting the strip, one of which is connected to a fold line - Google Patents

Abstract

The envelope (2) for posting letters, invoices, documents and similar has a tear-off strip (5) positioned entirely on the rear side of it and formed by two perforated runs (3,4) limiting the strip, one of which is connected to a fold line (7). The perforated runs are formed by special perforation patterns, which ensure that the tear-off strip can be removed in its entirety, without undesirable tear formations beign produced. The tear-off strip with the opening slip (6) are free from the adhesive application of the envelope closure flap (1).

Description

Envelope with tear-off strip.

The invention relates to an envelope for sending letters, invoices, documents and the like and wherein the envelope is provided with a tear-off strip which is positioned in its entirety on the rear side of the envelope and which is formed by two arranged and the strip bounding perforated webs of which one web connects to a fold line, being the edge of the envelope.

The opening of sealed envelopes is often done using a letter opener. When it is not at hand, the closing flap is pulled away from the envelope. However, this is often accompanied by a very irregular tear of the envelope, whereby, in addition to the risk of damage to the contents of the envelope, there is also the danger that the fingers can be cut on sharp tear edges.

Many versions of opener envelopes are known from the patent literature. However, the solutions that have been devised have never led to a practical version that is commercially available. This is due to the fact that all solutions devised to date have serious disadvantages.

The solutions registered to date can be divided into three main groups.

The first main group contains the envelopes that work with a special tear tape or strip to be applied separately. Examples of this main group are the patents US943103 (1909), US1433653 (1922) and US3653585 (1972) in which an envelope is described with a flexible pull strip on the side or a tear strip on the top of an envelope in combination with a partial perforation along the tear strip. The disadvantage of these solutions, however, is that the manufacture of these envelopes requires additional production runs that increase the cost price because additional material must be added.

The second main group contains the envelopes that work with a tear-off strip that lies over the side of the envelope. The patents US2527073 (1947) and DE3735408 (1989) are examples of this and describe a tear strip at the top and / or bottom of an envelope. These strips 2, however, lie over the back of the envelope, with the result that the tearing does not work properly and the contents can be damaged.

The third main group contains the envelopes with a tear-off strip which is arranged on one side of the envelope. Examples thereof are the patents FR7237423 (1972), CH537313 (1973), WO9323302 (1993), JP09066942 (1995), GB2323350 (1998) and WO0170585 (2001). These solutions do not work well because in practice the tearing off of a strip 10 bounded by simple perforation lines is not possible.

The failure of the solutions from the last main group is caused by two factors.

The first factor is the paper itself, which consists of a collection of fibers that are combined with a binder 15 in the paper. A fiber in the paper that is not parallel to the perforation and itself is not affected by the perforation initiates a crack formation that does not follow the pattern of the perforation line. As long as the tensile force is in the plane of the paper, the perforation line will usually be followed.

The second factor lies in the way in which a single tear-off strip is pulled off. This peeling is in principle done transversely to the plane of the paper. The tensile force is thereby perpendicular to the plane of the paper and the fiber lying transversely in the paper will therefore have much more opportunity to make the cracking deviate from the perforation line applied.

None of these proposed solutions have therefore been applied on a large scale to thin paper envelopes in practice.

The invention has for its object to solve these problems by using a fine perforation according to a specially arranged pattern, whereby it is possible to open an envelope with one single tearable strip on one side of the envelope without the aid of aids.

It should be noted that the patents GB2323350 and JP09066942 describe perforations that are not aligned. However, the British patent does not have a tear-off strip, but a way of opening that leaves the closing flap on the envelope 40, another way of opening. The Japanese patent does not work 3 because the tear-off strip with the indicated perforation will simply break if this strip itself is not reinforced with respect to the surrounding paper.

The invention is hereby described with reference to the following figures.

Figure 1 shows the portion of an envelope that relates to the envelope closing flap.

Figure 2 shows a perspective view of a partially torn envelope.

Figure 3 shows a detail of a properly functioning perforation pattern.

Finally, Figure 4 shows a detail of a properly functioning perforation pattern that partially lies on the fold line of the envelope closing flap.

The closing flap (1) of the envelope (2) is provided with two perforated tracks (3) and (4) which thereby enclose a tear-off strip (5). The web (3) is positioned against the fold line (7) of the closing valve (1) and the web (4) has a defined minimum distance to web (3) to prevent the intermediate tear-off strip (5) from breaking during the remove it. This distance is determined by the pattern as well as the nature of the perforation and the quality of the paper used. Furthermore, the strip (5) to be torn off with the release lip (6) must remain free from the gluing of the closing valve (1).

By pulling the release tab (6) transversely of the envelope (2) with a fingernail as indicated by the striped arrow (6a) in Figure 2, the strip (5) will be pulled away from the closing flap (1) without the the contents of the envelope are touched and without the tearable strip breaking. The contents of the envelope (2) can then be taken out of the envelope (2) without hindrance.

The perforations of the tracks (3) and (4) require a special pattern, a detail of which is shown in Figure 3. The perforations used must meet two requirements.

First, the perforations of the webs (3) and (4) must not seriously weaken the closing flap (1) of the envelope (2), as otherwise deformations can occur during folding or sealing the envelope (2).

40 Secondly, the perfection pattern of web (3) on the 0 '' '' 4 fold line (7) of the envelope (2) should be prevented than the tear runs away over the fold line (7) of the envelope (2) while the perforation pattern of web (4) must prevent the tear from entering the strip (5) when opening the envelope (2), as a result of which it could then break.

Figure 3 shows a perforation pattern in which a row of relatively short oblique incisions (8) with center line (3a) is arranged flush against the folding line (7) of the closing flap (1) and a row of relatively long oblique incisions (9) with axis (3b) positioned at some distance from the axis (3a). The oblique incisions (8) run at an angle of about thirty degrees away from the folding line (7) of the closing flap (1) towards the tear-off strip (5), viewed in the tearing direction. The oblique incisions 15 (9) run away at an angle of about thirty degrees just from the tear-off strip (5) towards the folding line (7), viewed in the tearing direction.

The pitch (s) of the perforation pattern is of the order of four to five millimeters, but can also be selected larger or smaller. In Figure 3, the short incision (8) is approximately two millimeters long and the long incision (9) is approximately three millimeters long. The location of the short incision (8) relative to the long incision (9) is also essential. When the tear-off strip (5) is torn off, the long incision (9) ensures that the tear of the strip (5) runs away. The short incision (8) ensures that the tear is returned to the strip so that the tear cannot run uncoordinated over the fold line (7).

The perforation tape (4) can be a mirrored representation of the perforation tape (3), but can also be another pattern that does meet the required conditions.

All of these patterns can be mechanically applied with rotating cutting blades or punching punching knives in one process pass. Perhaps it is also possible to make the incisions with laser technology.

In the production of envelopes, the perforation path (3) can disrupt the folding process of the closing flap because the closing flap is weakened by the perforation with center line (3a). This problem 40 can be solved by placing the folding line (7) precisely on the center line (3a), perhaps in combination with a linear perforation (7a) between the incisions (8) exactly on the folding line (7) of the envelope as is shown in Figure 4. Half of the incision (8) lies on the front side 5 of the envelope (2) and therefore falls over the fold line (7). The portion of the incision (8) shown in dotted lines lies on the front side of the envelope (2).

It is also possible to weaken the desired folding line itself with a linear perforation in such a way that the folding, as it were, is automatically achieved on this linear perforation which is shown in Figure 3 with a broken line on the folding line (7).

The tearable strip (5) can also be applied to the underside of the envelope (2) in the case of envelopes with glued edges where a glued flap (1 ') is present, as in figure 2 with the elements (3') indicated in dotted lines, ( 4), (5 ') and (6') are shown, taking care that the tear-off strip (5 ') with lip (6') is not glued.

The envelope with tear-off strip according to the invention is not limited to the exemplary embodiments shown in the figures and described in the foregoing. There can be varied in many ways within the scope of the invention in types and sizes of envelopes, in width of the strip to be used, instead of the strip on the envelope and in the form and design of perforation patterns which must of course suffice. to the two quality requirements that, firstly, the strength of the envelope must not seriously decline and, secondly, upon tearing, the tear may not run away either to the front of the envelope or to the tearable strip itself.

For example, the perforation bands (3) and (4) can contain different perforation patterns that are not mirror-image and the pitch of the perforation pattern can be freely chosen within reasonable limits. The shape of the perforation can also be adapted to the material used for the envelope.

The invention is not limited in use in other situations or applications.

40 * K -) ^

Claims (12)

1. Envelope for sending letters, invoices, documents and the like and wherein the envelope is provided with a tear-off strip which is positioned in its entirety at the rear of the envelope and which is formed by two perforated webs arranged and bounding the strip, of which one web connects to a fold line, being the edge of the envelope, characterized in that the perforation pattern of each of the perforated webs is made up of at least two separate incisions offset with respect to each other per stitch of the perforation pattern, both of which incisions with respect to each other and with respect to the direction of the perforation path 15 have different angles that are not equal to zero degrees, the axes passing through the two separate incisions staggered relative to each other not coinciding, the incisions being with their center line closest to the fold line lie the tear of the paper 20 leading to the tear-off strip, the incisions farther away from the fold line with their center line leading away the tear of the paper from the tear-off strip toward the fold line, and wherein the perforation pattern of the perforation path that the other side of the tear-off strip 25 defines the mirror image of the perforation path adjacent to the fold line of the envelope. 2. Envelope with tear-off strip according to claim 1, characterized in that the two incisions per stitch of the perforation path located on the fold line of the envelope 30 have the same length that the incisions closest to the fold line with their center line have an angle of about thirty degrees with the fold line of the envelope closing flap, are directed towards the tearable strip as seen from the tearing direction, and that the incisions that are further distant from the fold line with their center line of approximately thirty degrees with respect to the folding line and directed towards the folding line as seen from the tearing direction. 3. Envelope with tear-off strip as claimed in claim 1, characterized in that the two incisions per stitch of the perforation path located on the fold line of the envelope do not have the same length that the relatively long incisions 15 with their center line are closest to the fold line, have an angle of about thirty degrees with the fold line of the envelope closing flap and are directed towards the tearable strip as seen from the tearing direction, and that the short incisions with their center line are farther away from the folding line, have an angle of around thirty degrees with respect to the folding line and are directed towards the folding line as seen from the tearing direction. 3. Envelope with tearable strip as claimed in claim 40, characterized in that the two incisions per stitch of the perforation path located on the fold line of the envelope do not have the same length that the relatively short incisions with their center line being closest to the fold line, having an angle of about thirty degrees with the fold line of the envelope closing flap and facing the tearable strip as seen from the tearing direction, and that the long incisions with their center line farther away are located from the folding line, have an angle of about thirty degrees with respect to the folding line and are directed towards the folding line as seen from the tearing direction. 4. Envelope with tear-off strip according to claims 1, 2 or 3, characterized in that the pitch of the perforation pattern is greater than or equal to one millimeter and smaller or equal to eight millimeters. 5. Envelope with tear-off strip according to claims 1, 2, 3 or 4, characterized in that the end of the cut adjacent to the tear-off strip coincides with the start of the cut that does not adjoin the tear-off strip. Envelope with tear-off strip according to claims 1, 2, 3, 4 or 5, characterized in that the fold line is the fold line of the envelope closing flap. 7. Envelope with tear-off strip according to claims 1, 2, 3, 4 or 5, characterized in that the folding line is the folding line of the lower glued envelope of the envelope. 8. Envelope with tearable strip as claimed in claims 1, 2, 3, 4 or 5, characterized in that the fold line is the fold line of a laterally glued overlap of the envelope. 9. Envelope with tear-off strip as claimed in claims 1, 2, 3, 4, 5, 6, 7 or 8, characterized in that the perforation pattern of the perforation track bounding the other side of the tear-off strip is an image of the perforation path adjacent to the fold line of the envelope. 10. Envelope with tear-off strip as claimed in claims 1, 2, 3, 4, 5, 6, 7 or 8, characterized in that the perforation pattern of the perforation path which limits the other side of the tear-off strip neither the mirror image nor is the image of the perforation path adjacent to the fold line of the envelope. 11. Envelope with tear-off strip as claimed in claims 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, characterized in that the perforation pattern is arranged with the aid of punching punching knives or rotating cutting knives. 12. Envelope with tear-off strip according to claims 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, characterized in that the perforation pattern is provided with the aid of laser cutting technology. "!! ; * ·> ·· - ...