EP1997744A1

EP1997744A1 - Improved envelope with facilitated opening

Info

Publication number: EP1997744A1
Application number: EP07425321A
Authority: EP
Inventors: Amedeo Blasetti
Original assignee: Blasetti SpA
Current assignee: Blasetti SpA
Priority date: 2007-05-25
Filing date: 2007-05-25
Publication date: 2008-12-03

Abstract

The envelope comprises a front face (10) and a rear face (12). The front face (10) has a first side (18) in common with the rear face (12), and has a window (32) which is closed by a film (34) of transparent material, the perimeter region (36) of which is associated with the portions of the inner surface of the front face (10) which surround the window. Respective punchings (38) arc also provided in facing angular areas of the faces (10, 12), and in a portion of the perimeter region of the film (34), there is provided a line of weakening (40), an end section of which is contained between the angular areas of the faces (10, 12) in which the punchings (38) are provided.

Description

The present invention relates to the field of envelopes.
In greater detail, it relates to an envelope comprising a front face and a rear face, the said front face having a first side in common with the rear face, and having a window which is closed by a film of transparent material, the perimeter region of which is associated with the portions of the inner surface of the front face which surround the said window, and respective punchings being provided in facing angular areas of the said faces.
In a known envelope of the aforementioned type, a thread is associated with one of its sides, starting from the opposite angular areas where the punchings are provided. Tearing of the latter gives rise to opening of the envelope in the position of the thread, in a facilitated and regular manner, thus avoiding abnormal tearings and breakages which can damage the content.
However, the association of the thread with the paper material which constitutes the envelope complicates significantly the process of production of the latter, and increases its costs substantially.
The object of the present invention is thus to provide an envelope with facilitated opening, which eliminates the above-described problems of the known types.
This object is achieved by means of an envelope of the type indicated at the beginning of the present description, and which is characterised in that, in at least one portion of the perimeter region of the film, there is provided at least one line of weakening, an end section of which is contained between the said angular areas of the faces.
The facilitated opening of the envelope according to the invention can take place in the position of the line of weakening, which for example is produced by means of punching. The means which permits this opening therefore consists of the film of transparent material itself, which must be present in any case, such that the addition of a further element such as the thread is not required. This therefore provides simplification of the process of production of the envelope and reduction of its costs.
According to a particular embodiment of the envelope according to the invention, it is possible to associate a strengthening thread with the film of transparent material, such as to make the opening of the envelope even more regular. This possibility is particularly advantageous in the case in which the paper material which constitutes the envelope has a high gram weight, and/or the film of transparent material is very thin.
This embodiment is also advantageous compared with the known easy-opening envelopes. In fact, according to the invention, the thread is associated with the film of transparent material, and not with the paper material which constitutes the body of the envelope, as is the case in the known art. This simplifies the production process considerably, and makes it possible to use a decidedly smaller quantity of thread. Firstly, since the extent of the film is smaller than that of the paper body of the finished envelope, the length of thread present in the latter is shorter. Secondly, a roll of blank film with which the thread is associated can usefully be used in its entirety, whereas the roll of paper with which the thread is associated must also be used to produce portions of envelope other than those which must be associated with the thread in the finished envelope. Consequently, from these portions there must be eliminated the region in which the thread is located, thus creating scrap, with the consequent financial disadvantages caused by the waste of material and the problems associated with its disposal.
Further advantages and characteristics of the present invention will become apparent from the following detailed description, provided by way of non-limiting example with reference to the attached drawings, in which:

figure 1 is a view from the rear of a sheet of paper material from which there are obtained the various faces, tabs and wings of an envelope according to the invention; and
figure 2 is a front view of the envelope according to the invention.

An envelope comprises a front face 10, a rear face 12, a closure tab 14 and two wings 16, which are obtained from a single sheet of paper material, as illustrated in figure 1.
The front face 10 has a rectangular perimeter formed by a first side 18 in common with the rear face 12, by a second side 20 opposite the first side 18 and in common with the closure tab 14, and by a third and fourth side 22, 24 which are opposite one another and are respectively in common with one of the wings 16.
The rear face 12 has a perimeter formed by the first side 18 in common with the front face 10, by a second, concave side 26 opposite the first side 20, and by a third and fourth side 28, 30 which join the respective opposite end sections of the first and second sides 18, 26.
The front face 10 also has a window 32 with a rectangular profile, which reproduces the dimensions on a reduced scale, and is located in the lower right-hand portion of the face 10, in the vicinity of the first and third sides 18, 22. The window 32 is closed by a film 34 of transparent material with a rectangular profile defined by sides which are substantially respectively parallel to those of the front face. In order to obtain this closure, the perimeter region 36 of the film 34 is associated, for example by means of gluing, with the portions of the inner surface of the front face 10 which surround the window 32.
In a known manner, in the configuration of use illustrated in figure 2, the rear face 12 is folded around the side 18, such as to be disposed behind the front face 10, with its sides 28, 30 being made to adhere to the wings 16, which in turn have previously been folded behind the front face 10 around the sides 22, 24. The faces 10, 12 thus define a space which is closed at the base and laterally, in which there can be inserted whatever is required, and can subsequently be closed by means of the tab 14.
Subsequently, in the opposite angular areas of the front 10 and rear 12 faces, which are defined by the intersection of the respective first 18 and third 22, 28 sides, there are provided respective punchings 38 with development in the form of an arch.
In the perimeter region 36 of the film 34, there is provided a line of weakening 40, which is substantially parallel to the third side 22 of the front face 10, and has a lower end section contained between angular areas of the faces 10, 12 in which the punchings 38 are provided. A strengthening thread 42 is associated with the part of the film 34 which is contained between the line of weakening 40 and the third side 22 of the front face 10. Since the height of the film 34 is distinctly less than the length of the third side 22, the length of the thread 42 necessary is reduced by the same extent in comparison with the conventional envelopes, in which the thread is associated with this side of the paper body of the envelope. The saving in thread guaranteed by the invention is in reality even greater than that determined by these dimensional factors, if it is considered that the process of association of the thread with the paper material necessarily involves the production of scrap, as previously indicated.
When the envelope is to be opened, it is sufficient to tear the punchings 38 of the faces 10, 12, such as to initiate the rupture of the film 34 along the line of weakening 40, which in turn gives rise to tearing of the faces 10, 12 in a substantially regular manner parallel to the third side 22, thus preventing abnormal renting and rupture which may damage the contents.
Naturally, without departing from the principle of the invention, the details of the embodiments and forms of implementation can be varied widely compared with those of the description provided purely by way of example, without for this reason departing from the scope of the invention as defined in the attached claims. In particular, the association of the strengthening thread with the film can be considered as a preferred option, but it is not necessary.

Claims

Envelope comprising a front face (10) and a rear face (12), the said front face (10) having a first side (18) in common with the rear face (12), and having a window (32) which is closed by a film (34) of transparent material, the perimeter region (36) of which is associated with the portions of the inner surface of the front face (10) which surround the said window, and respective punchings (38) being provided in facing angular areas of the said faces (10, 12),
the said envelope being characterised in that, in at least one portion of the perimeter region of the film (34), there is provided at least one line of weakening (40), an end section of which is contained between the angular areas of the faces (10, 12) in which the said punchings (38) are provided.
Envelope according to Claim 1, characterised in that it comprises a closure tab (14), the said front face (10) having a second side (20) opposite the first side (18) and in common with the said closure tab (14).
Envelope according to any one of the preceding claims, characterised in that the said front face (10) has a rectangular perimeter formed by the said first and second sides (18, 20), as well as by a third and fourth side (22, 24) which are opposite one another, the said front face (10) having the third and fourth sides (22, 24) in common with a respective wing (16) with which there are associated lateral regions of the rear face (12).
Envelope according to Claim 3, characterised in that the said rear face (12) has a perimeter formed by the first side (18) in common with the front face (10), a second side (26) opposite the first side (18), and a third and fourth side (28, 30) which join the respective opposite end sections of the said first and second sides (18, 26).
Envelope according to Claim 4, characterised in that the angular areas of the front (10) and rear (12) faces in which the said punchings (38) are provided are defined by the intersection of the respective first (18) and third (22, 28) sides.
Envelope according to any one of the preceding claims, characterised in that the said film (34) of transparent material has a rectangular profile defined by sides which are substantially respectively parallel to those of the front face (10), and the said line of weakening (40) is substantially parallel to the third side (22) of the front face (10).
Envelope according to Claim 6, characterised in that a strengthening thread (42) is associated with the part of the film (34) which is contained between the said line of weakening (40) and the third side (22) of the front face (10).