GB2234489A - Envelope - Google Patents

Abstract

A security envelope e.g. for invoices, has an insertion slot 6 on its rear wall 4 which has an adhesive area on each side, normally covered by a respective peelable backing sheet 10, 12 partially overlapping (14, 16) the slot, so that after the peelable sheets 10, 12 have been removed the envelope can be attached to a package and simultaneously sealed. <IMAGE>

Description

Envelope This invention relates to envelopes for documents and particularly to envelopes adapted to be attached to boxes or packets so as to enable invoices or the like to be enclosed with the contents. Envelopes of this kind normally have adhesive on one side which is covered with a peelable backing sheet made of paper carrying a coating of release agent. However, this can be difficult to remove and also, when it is made of conventional-1Raterials, the insulating properties of these materials can cause difficulties in manufacture, because of the need to heat seal parts of the assembly.

Accordingly the present invention provides an envelope including a front wall and a rear wall, the rear wall having a slot for insertion of contents into the envelope, so as to divide the outer surface into two distinct areas, and carrying a layer of adhesive on at least part of each area, around the slot, whereby the envelope can be attached to a container by means of the adhesive, after insertion of the contents, while effectively sealing the envelope closed; each said adhesive carrying area being covered by a peelable backing sheet which partly overlaps the said slot so as to facilitate removal of the backing sheet.

Preferably the backing sheet is made of high density polyethylene which has good thermal conductivity.

One embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which Figure 1 is a perspective view of an envelope from the rear; Figure 2 is a vertical cross-section through the envelope of Figure 1.

Referring to the drawings the envelope comprises a front wall 2 and a rear wall 4. A slot 6 extends across the rear wall near its top edge 8 and is of sufficient width to allow the insertion of a document.

The slot 6 effectively divides the outer surface of the rear wall into two distinct areas each of which is covered with adhesive (usually of the pressure sensitive type). Backing sheets 10 and 12 are applied over these areas to prevent premature adhesion of the envelope to adjacent surfaces.

Each backing sheet has a respective edge flap portion 14, 16 which overlies the corresponding edge of the slot 6, thus providing a "finger-lift" area which facilitates removal of the backing sheet. A pre-folded line 18, 20 may be provided as shown in Figure 1, so as to raise the flap above the surface.

Claims (4)

1. An envelope including a front wall and a rear wall, the rear wall having a slot for the insertion of contents into the envelope, so as to divide the outer surface into two distinct areas, and carrying a layer of adhesive on at least part of each area, around the slot, whereby the envelope can be attached to a container by means of the adhesive, after insertion of the contents, while effectively sealing the envelope closed; each said adhesive carrying area being covered by a peelable backing sheet which partly overlaps the said slot so as to facilitate removal of the backing sheet.

2. An envelope according to claim 1 in which the backing sheet comprises high density polyethylene.

3. An envelope according to claim 1 or claim 2 further comprising a pre-folded line in the backing sheet, adjacent the edge which overlies the slot, so as to form a flap which is raised above the surface of the envelope.

4. An envelope substantially as herein described with reference to the accompanying drawings.