GB2207121A - Envelopes - Google Patents

Abstract

An envelope for correspondence and the like having a closure flap 7 adhesively (8) coated for the sealing thereof and arranged to seal the envelope completely, a ripper filament e.g. an adhesive tape 11, secured internally of the envelope and positioned so as to lie along a line of weakness e.g. at a fold line 4, and having an end portion 12 projecting from the envelope to form a gripper tab which is positioned to lie at one of the corners of the envelope remote from the flap, whereby the envelope can be opened by ripping the filament along the line of weakness. <IMAGE>

Description

IMPROVEMENTS IN ENVELOPES FOR CORRESPONDENCE This invention relates to sealable envelopes of the kind commonly used for conveying correspondence.

The recipients of correspondence in sealed envelopes often have difficulties in opening the envelopes, and implements such as letter knives cannot be used without a risk of damaging the correspondence itself. It is among the objects of this invention to provide an envelope which can be fully sealed, but which is capable of being readily opened to afford access to the contents without causing them damage.

According to the present invention an envelope for correspondence and the like has a closure flap adhesively coated for the sealing thereof and arranged to seal the envelope completely (ie without leaving a throat), a ripper filament secured internally of the envelope and positioned so as to lie along a line of weakness and an end portion projecting from the envelope to form a gripper tag which is positioned to lie at one of the corners of the envelope remote from the flap, whereby the envelope can be opened by ripping the filament along the line of weakness.

The ripper filament may comprise a narrow piece of plastic tape, and may carry a self adhesive coating.

Preferably the ripper filament is adhered so as to overlie a fold of the envelope, and in this case the fold may be formed as the line of weakness.

In one construction the gripper tab is folded and lightly adhered to the envelope. In an alternative construction the gripper tab may be formed by the end of the filament being doubled back on itself within the envelope so as to underlie a zone defined by a printed or lightly scored indicator line extending across the corner. In this case the doubled tape produces a slight thickening in the corner zone which can be sensed by the fingers, thus facilitating engagement by a thumbnail to tear out the strip and open the envelope.

The invention will now be further described with reference to the accompanying drawings in which: Figure 1 is a rear view of a conventional paper envelope as presently in use, Figure 2 is a rear view of a first embodiment of a paper envelope according to the invention, Figure 3 is a rear view of the second embodiment of an envelope according to the invention, Figure 4 is a detail of one corner of a paper envelope according to the invention, Figure 5 is a detail of one corner of another paper envelope according to the invention, Figure 6 is a section or end elevation through a fold of a paper envelope according to the invention prior to folding and, Figure 7 shows the assembly of Figure 5 after folding.

Referring first to Figure 1, this shows a conventional paper envelope 1 of known kind having side folds 2 from which side flaps 3 extend and a lower fold 4 from which a back panel 5 extends, the back panel 5 being adhered to the side flaps 3. An upper fold 6 has a closure flap 7 extending therefrom, the flap 7 having an adhesive 8 applied to its undersurface for adhesion to the side flaps 3 and back panel 5. The adhesive 8 extends only part way to the upper fold 6 so as to leave a throat 9 at each end of the closure flap 7. The provision of the throat 9 is necessary to facilitate the insertion of a letter knife 10 by a recipient wishing to open the envelope.

Apart from the fact that the throat 9 facilitates illicit opening of the envelope of Figure 1, it is difficult to use a letter knife without risking damage to the correspondence contained within the envelope.

Turning now to Figures 2 and 3, these show paper envelopes generally similar to that of Figure 1 and the same reference numerals are used to indicate the same elements.

In the embodiments of Figures 2 and 3 however the adhesive 8 is carried fully to the top fold 6 so that the flap 7 completely seals the envelope and does not leave throats 9 at each end of the flap.

Within each of the envelopes of Figures 2 and 3, a ripper filament, in the form of a tape 11 made of plastics film, is secured in the envelope adjacent to a fold (one of the folds 2 in Figure 2 and the fold 4 in Figure 3). The tape 11 may for example carry a late self-adhesive coating whereby it is secured adjacent to the appropriate fold within the envelope.

One end of the tape 11 projects from a corner of the envelope to form a gripper tab 12 for use by the recipient in ripping the tape 11 along the fold, the tab being located at a corner remote from the flap 7.

As best seen in Figure 6, the gripper tab 12 may be folded down and lightly adhered to the back panel 5 so that the risk of inadvertently opening of the envelope is reduced.

In a variant, the tape 11 projects at both ends from the envelope to form two gripper tabs, which are adhered to the back panel 5, and either of which can be used to open the envelope. The use of a relatively low tack adhesive is preferred for use on the tape 11. This will be sufficient to hold the tape in position in the envelope whilst making it relatively easy to peel the gripper tab from the back panel 5 when a recipient wishes to open the envelope.

Alternatively, and as shown in Figure 5, the end 12 of the tape 11 may double back on itself within the envelope so as to underline a zone 18 defined a printed or lightly scored indicator line 17 extending across the corner. The doubled tape produces a slight thickening in the corner zone which can be sensed by the fingers, thus facilitating engagement by the thumbnail to tear out the strip and open the envelope.

Figures 4 and 5 show embodiments in which the tear out strip is gripped from the back of the envelope. It will be appreciated that the same features may be provided on the front panel if required.

Figures 6 and 7 show how it is ensured that a clean tear will form when the tape is torn from the envelope. Prior to folding into an envelope, the paper envelope blank, of which a detail is shown at 13, is scored at 14 so as to crush and weaken the paper fibres along the line of scoring.

A self-adhesive tape 15 which ultimately also serves as a ripper filament, is adhered to the blank so as to overlie the scored line 14. As best seen in Figure 7, after folding, the scored line 14 and the tape 15 lie along the fold 16 internally of the envelope. Whilst the envelope is in course of conveyance, the tape 15 serves as a reinforcement for the weakened scoreline 14. Upon receipt however the tape can be readily ripped from the envelope to form a clean tear along the scoreline.

It will be appreciated that the invention is not limited to paper envelopes. Any material may be used which will rip when formed into an envelope incorporating a ripping filament as described above. Nor is the invention limited to the use of plastics films in the formation of the ripping filaments. Strong threads, for example, may be used. Polymeric paperlike materials such as those sold under the Registered Trade Marks TYVEK and SYNTEAPE may advantageously be used to form such filaments in white envelopes, since they are white in colour and can be incorporated unobtrusively.

Claims (8)

1. An envelope for correspondence and the like having a closure flap adhesively coated for the sealing thereof and arranged to seal the envelope completely, a ripper filament secured internally of the envelope and positioned so as to lie along a line of weakness and having an end portion projecting from the envelope to form a gripper tab which is positioned to lie at one of the corners of the envelope remote from the flap, whereby the envelope can be opened by ripping the filament along the line of weakness.

2. An envelope as claimed in Claim 1, in which the ripper filament comprises a narrow piece of plastic tape.

3. An envelope as claimed in Claim 1 or Claim 2, in which the ripper filament carried a self adhesive coating.

4. An envelope as claimed in any one of Claims 1 to 3, in which the ripper filament is adhered so as to overlie the fold of the envelope.

5. An envelope as claimed in Claim 4, in which the fold is formed as the line of weakness.

6. An envelope as claimed in any one of the preceding Claims, in which the gripper tab is folded down and lightly adhered to the envelope.

7. An envelope as claimed in any one of Claims 1 to 5, in which the gripper tab is formed by the end of the filament being doubled back on itself within the envelope so as to underlie a zone defined by a printed or lightly scored indicator line extending across a corner.

8. An envelope for correspondence and the like substantially as described herein with reference to and as shown in the accompanying drawings.