The present invention, in some embodiments thereof, relates to envelopes and, more particularly, but not exclusively, to tamper-resistant and tamper-evident envelopes.

Envelopes are commonly used for packaging written/printed material and relatively small items which are to be sent by a sender in a first location to a receiver in a second location. These may include money, notes, classified documents, valuables, among others. Usually, the envelope is entrusted to a third party, which may be a complete stranger, who assumes responsibility for transporting the envelope from the sender to the receiver. In some instances, transport of the envelope may be done by a postal service. In other instances, a private delivery service such as a courier may be used. Regardless of who transports the envelope, a main concern of the sender, and frequently also the receiver, is that the envelope be received at the second location without having been tampered with. If tampered with, this may be an indication that the contents inside the envelope has been meddled with, and its confidentiality violated.

Tamper-resistant and tamper-evident envelopes are known in the art, generally designed so as to allow the third party transporting the envelope (hereinafter may be referred to as "courier" or "deliverer) and/or the receiver to visibly corroborate tampering with the envelope.

US Patent No. 5,727,686 "TAMPER-EVIDENT SECURITY ENVELOPE", relates to "A tamper-evident envelope has a first layer of paper-containing material and a second layer of paper-containing material attached to each other along a number of seams. Each seam includes a pattern embossed and/or perforated through both layers along a major part of the seam. If the envelope is opened and resealed along one of these seams, the embossed or perforated pattern is corrupted, thereby making the unauthorized opening of the envelope readily apparent to an intended recipient."

US Patent No. 5,918,983 "SECURITY ENVELOPE", relates to "A security envelope for transporting valuable documents and articles includes a thin header formed of thin frangible material secured to the back panel having an adhesive layer that seals the header to the front panel upon folding and pressing closed. An inner layer of adhesive on the inner surface of the back panel seals the inner front and back panel surfaces to close the envelope chamber and extends further toward the envelope bottom than the header adhesive layer when sealed to prevent tampering tool access to the envelope chamber. Application of tampering heat will shrivel the header and cold sufficient to release the inner adhesive layer will cause pieces of the outer adhesive layer to break off and fall away. Printed indicia on the header inner surface and a transparent flood coat on the inner header surface will adhere to the header adhesive layer and aid in the tampering attempt indication."

US Publication No. 2008/0156855 "SECURE ENVELOPE AND METHOD FOR SECURING INFORMATION", relates to "A windowed envelope is disclosed comprising: a first panel with an interior and an exterior side; a second panel attached to the first panel to define an interior portion having opposite side edges, a closed edge portion and an opening portion opposite the closed edge portion to provide access to the interior portion of the envelope; and a flap for sealingly adhering to an exterior surface of the first panel. The flap has an interior and an exterior side and is attached to the second panel at an edge of the second panel opposite the closed edge portion. The envelope comprises thereon an adhesive layer on the interior side of the flap comprising an adhesive; wherein a non-transparent window is located on the first panel or the second panel. The window comprises a reducible dye and a microencapsulated reducing agent, which is adapted to irreversibly change to a transparent window upon heating the non-transparent window to a temperature above room temperature."

Additional background art includes US5,474,818; US4,566,627; US2,230,849; DE344106; and in particular US 2005/0116014 apart from BE384979.

There is provided in accordance with an exemplary embodiment of the present invention, a tamper-resistant envelope comprising a first and a second panel joined together along at least one tamper-evident seam to form a pocket therebetween having an opening, the tamper-evident seam having a width configured to provide at least one tamper-evident feature, the tamper-evident feature including at least one of embossing and perforations in the seam formed of both the first and second panels, wherein the tamper-evident seam is provided with at least one of the embossing and perforations formed through the first and second panels; and a flap comprising a tamper-evident adhesive, the flap distally connected to the first panel along a fold line, wherein the adhesive is disposed on a single side of the fold line, the flap adapted to adhere to at least a portion of the first panel and at least a portion of the second panel when folded along the fold line, the adhesive configured to allow the flap to substantially seal the opening, wherein the adhesive is adapted to change a color as a result of tampering with the adhesive; and
wherein the first and second panels include a laminate film susceptible to a wetter, the laminate film configured to change color when exposed to the wetter;
wherein the adhesive comprises an adhesive film configured to adhere to a portion of the tamper-evident feature including the at least one tamper-evident seam formed of the joined-together first and second panels;
wherein the adhesive film, when adhered to a portion of the tamper-evident feature including the at least one tamper-evident seam formed of the joined-together first and second panels, is configured to prevent access to the sealed opening from any direction using a mechanical means configured to be inserted under the flap for opening the flap.

In an exemplary embodiment of the present invention, the at least a portion of the first panel comprises an area between an opening of the pocket and a fold line along which the flap is folded.

In an exemplary embodiment of the present invention, the at least one tamper-evident seam comprises three tamper-evident seams.

In an exemplary embodiment of the present invention, the at least a portion of the second panel comprises at least a portion of an area between an opening to the pocket and a flap sealing line demarcating a positioning marker for a distal end of the flap.

In an exemplary embodiment of the present invention, the tamper-evident adhesive substantially covers an area extending from the fold line to a distal end of the flap.

In an exemplary embodiment of the present invention, the tamper-evident adhesive is adapted to change colors as a result of tampering with the adhesive.

In an exemplary embodiment of the present invention, the tamper-resistance envelope comprises a laminate film coating at least a portion of an inner face of the first panel and of an inner face of the second panel. Optionally, the at least a portion of the inner face of the first panel and of the second panel includes the pocket. Additionally or alternatively, the laminate film comprises a polymer material substantially resistant to a wetter adapted to temporarily make the first and/or the second panel optically transparent.

In an exemplary embodiment of the present invention, the at least one tamper-evident seam comprises symbols. Optionally, the at least one tamper-evident seam comprises an electric conductor for activating a warning when an open circuit is formed in the conductor.

In an exemplary embodiment of the present invention, the tamper-resistance envelope comprises a radio frequency identification tag for local reading of the envelope's identification.

In an exemplary embodiment of the present invention, the tamper-resistance envelope comprises a global positioning system device for determining a location of the envelope.

There is provided in accordance with an exemplary embodiment of the present invention, a method of using a tamper-resistant envelope, the method comprising checking an external tampering-evident feature in the envelope while transported from a sender in a first location to a receiver in a second location, and checking the external tampering-evident feature and an internal tampering-evident feature in the envelope when received at the second location by the receiver;
wherein the tamper-resistant envelope comprises:

• a first and a second panel joined together along at least one tamper-evident seam to form a pocket therebetween having an opening, the tamper-evident seam having a width configured to provide at least one tamper-evident feature, the tamper-evident feature including at least one of embossing and perforations in the seam formed of both the first and second panels, wherein the tamper-evident seam is provided with at least one of the embossing and perforations formed through the first and second panels; and
• a flap comprising a tamper-evident adhesive, the flap distally connected to the first panel along a fold line, wherein the adhesive is disposed on a single side of the fold line, the flap adapted to adhere to at least a portion of the first panel and at least a portion of the second panel when folded along the fold line, the adhesive configured to allow the flap to substantially seal the opening, wherein the adhesive is adapted to change a color as a result of tampering with the adhesive;
• wherein the first and second panels include a laminate film susceptible to a wetter, the laminate film configured to change color when exposed to the wetter;
• wherein checking the external tamper-evident feature for evidence of tampering comprises:
  • at least one of checking a symbol on a tamper-evident seam for damage and viewing a tamper-evident adhesive through a window on the flap; and
  • wherein checking the internal tamper-evident feature for evidence of tampering comprises:
    • at least one of inspecting a tamper-evident adhesive for at least one of change of color and discoloration and
    • inspecting a tamper-evident adhesive for symbols unique to the adhesive;
    • wherein the adhesive comprises an adhesive film configured to adhere to a portion of the tamper-evident feature including the at least one tamper-evident seam formed of the joined-together first and second panels;
    • wherein the adhesive film, when adhered to a portion of the tamper-evident feature including the at least one tamper-evident seam formed of the joined-together first and second panels, prevents access to the sealed opening from any direction using a mechanical means inserted under the flap for opening the flap.

There is provided in accordance with an exemplary embodiment of the present invention, a method for producing a tamper-resistant envelope comprising laminating a sheet for making panels with an optically opaque material, preparing a first panel and a second panel from the sheet wherein the first panel includes a flap distally connected along a fold line, joining together the first panel and the second panel along at least two tamper-evident seams to form a pocket between the panels, the pocket having an opening, the tamper-evident seams each having a width configured to provide at least one tamper-evident feature;
at least one of embossing and, perforating symbols along the at least two seams to provide the tamper-evident feature in each the seam formed of both the first and second panels, wherein each the tamper-evident seam is provided with at least one of embossing and perforations formed through the first and second panels, cutting a window in the flap, applying an adhesive to the flap on a single side of the fold line, covering the adhesive with a removable strip, marking a flap seal line on the second panel, and applying an identification and a tracking marking to the first panel and the second panels;
wherein the adhesive comprises an adhesive film configured to adhere to a portion of the tamper-evident feature including the at least one tamper-evident seam formed of the joined-together first and second panels;
wherein the adhesive film, when adhered to a portion of the tamper-evident feature including the at least one tamper-evident seam formed of the joined-together first and second panels, prevents access to the sealed opening from any direction using a mechanical means inserted under the flap for opening the flap.

Unless otherwise defined, all technical and/or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention pertains. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the invention, exemplary methods and/or materials are described below. In case of conflict, the patent specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and are not intended to be necessarily limiting.

Some embodiments of the invention are herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of embodiments of the invention. In this regard, the description taken with the drawings makes apparent to those skilled in the art how embodiments of the invention may be practiced.

In the drawings:

• FIG. 1A schematically illustrates a view of an exemplary tamper-resistant envelope, according to some embodiments of the present invention;
• FIGs. 1B and 1C schematically illustrate side views of the tamper-resistant envelope of FIGURE 1A with open flap and closed flap, respectively, according to some embodiments of the present invention;
• FIGs. 2A and 2B schematically illustrate a view of a laminated inner face of a front panel and a rear panel, respectively, in an exemplary tamper-resistant envelope, according to some embodiments of the present invention;
• FIG. 2C schematically illustrates a side view of the tamper-resistant envelope in FIGs. 2A and 2B, according to some embodiments of the present invention;
• FIG. 3 schematically illustrates a view of an exemplary tamper-resistant envelope including tamper-viewing windows, according to some embodiments of the present invention;
• FIGs. 4A and 4B schematically illustrate views of an exemplary front panel and rear panel respectively, including markings, in an exemplary tamper-resistant envelope, according to some embodiments of the present invention;
• FIG. 5 schematically illustrates a view of an exemplary tamper-resistant envelope including electrically conducting tamper-evident strips, according to some embodiments of the present invention;
• FIG. 6 is a flow chart illustrating an exemplary method of using a tamper-resistant envelope, according to some embodiments of the present invention; and
• FIG. 7 is a flow chart illustrating an exemplary method of producing a tamper-resistant envelope, according to some embodiments of the present invention.

The present invention, in some embodiments thereof, relates to envelopes and, more particularly, but not exclusively, to tamper-resistant and tamper-evident envelopes.

An aspect of some embodiments of the present invention relates to a tamper-resistant envelope formed from joining together a first panel and a second panel along three edges to form a pocket between the panels, the first panel extends beyond an opening to the pocket and includes an adherable flap which is adapted to be folded and adhered to both the first panel and the second panel for sealing the pocket. Adhering of the flap to both the first panel and the second panel substantially seals the opening of the pocket. Sealing the opening of the pocket prevents access to the opening (now sealed) from any direction using mechanical means without noticeable damage being caused to the envelope. This substantially prevents tampering with contents placed inside the pocket without the tampering being evident (tamper-evident). Optionally, a tamper-evident feature in the envelope makes the envelope substantially tamper-resistant as a person wishing to tamper with the envelope will most probably desist from such action if the tampering will be evident. The mechanical means may include an object (tool) suitable to be inserted under a flap for opening the flap. Optionally, the mechanical means may include a use of force for pulling the flap.

In some embodiments of the present invention, the flap is adhered to the first panel and the second panel using a tamper-evident adhesive which provides a visual indication when the adhesive has been tampered with. Optionally, the adhesive may include a glue and provides an indication of an attempt having been made to change the adhesive properties of the glue, for example by trying to heat the glue to dissolve it, and/or by trying to freeze the glue to cause it to brittle and break. Optionally, the glue changes a color when exposed to temperatures which change its adhesive properties. Optionally, the adhesive properties of the glue are maintained throughout a temperature range from -45°C to 100°C. Optionally, the adhesive properties of the glue are maintained for temperatures above 100°C and/or below -45°C. Additionally or alternatively, the tamper-evident adhesive includes an adhesive tape. Optionally, the adhesive tape is a double-sided adhesive tape. Optionally, the tamper-evident adhesive includes an adhesive film. Optionally, the adhesive tape is a tamper evident tape model 120/87 produced by Label Tech Ltd, Israel, and includes PVC 50µm and an acrylic adhesive. Optionally, a visual message such as, for example, the word "VOID", is formed in the tamper-evident adhesive when tampered with. Additionally or alternatively, the flap may include a tamper-viewing window through which evidence of tampering with the tamper-evident adhesive may be viewed. Optionally, the visual message is displayed through the window. Optionally, the tamper-evident adhesive may include one or more symbols (may include characters, letters, numbers, logos, etc.) invisible to the naked eye and which serve to corroborate that the adhesive has not been replaced.

In some embodiments of the present invention, the first panel and the second panel are each laminated on an inner face with a material film resistant to a wetter or a wetting agent which may be applied to the envelope for attempting to make the panels temporarily transparent. The laminated inner faces, which are on the side of the first panel and the second panel forming the pocket, are adapted to provide a degree of opacity which substantially prevents viewing of the contents inside the envelope when the wetter is applied to outer faces of the panels (optically opaque). Optionally, the laminate film is a plastic film and includes a polymeric material such as, for example, polyethylene, polypropylene, or nylon, or any combination thereof. Optionally, the laminate film is a carbon-based laminate. Additionally or alternatively, the laminated film prevents liquids from reaching the contents inside the pocket (water-resistant). The laminate film is susceptible to the wetter and changes a color when exposed to the wetter. Additionally or alternatively, the laminate film is adapted to bloom through the panels when the wetter is applied to the panels and migrates through the panels to the laminate film. Laminating of the inner faces may be done by methods known in the art, and may include cold lamination. Optionally, hot lamination is used. Optionally, a bubble wrap liner is attached to the inner face of each panel for providing mechanical protection to the contents of the envelope (inside the pocket) from impact.

In some embodiments of the present invention, the three edges along which the first panel and the second panel are joined together to form the pocket each include a tamper-evident seam. The tamper-evident seam includes one or more perforated symbols along a major portion of the seam such that, if the envelope is opened along the edge comprising the seam, at least one of the symbols will be damaged. The damaged symbol may then be readily detected when the envelope is checked for tampering. Optionally, use of the tamper-evident seam is restricted to one of the three edges. Optionally, use of the tamper-evident seam is restricted to two of the three edges. Optionally, tamper-evident symbols are used on the flap. Additionally or alternatively, the tamper-evident seam is embossed with the one or more symbols. Optionally, the tamper-evident seam (and/or the flap) includes at least one dissimilar symbol. Optionally, the one or more symbols are all similar.

In some embodiments of the present invention, the tamper-evident seam may include an electrical conductor which extends along the seam and is connected to a power source in the envelope. Optionally, the power source is an external source which induces a current in the electric conductor by generating an electromagnetic field (EM) to which the envelope is exposed. Optionally, the electrical conductor includes an electrically conducting paint and/or film. When the seam is opened (which may include being cut), an open circuit is created in the electrical conductor which is detected by a sensor in the envelope. Optionally, the power source includes the sensor. Additionally or alternatively, a visual warning is displayed in the envelope by a chemically reactive display responsive to the open circuit (for example, a change in color of a paint or coating as in electrochromic paints and/or thermochromic paints). Optionally, the visual warning is displayed through a thin film LCD. Optionally, the warning is displayed through a clock visibly included in the envelope which displays the time and date when the open circuit was created. Optionally, the clock is activated by the tampering and counts a period of time since its activation (a counter). Optionally, an audible alarm is activated.

In some embodiments of the present invention, the electrical conductors are arranged in the envelope such that an open circuit occurs when the pocket is opened. Optionally, the conductors are arranged along the flap and the second panel such that separating the flap from the second panel results in an open circuit.

In some embodiments of the present invention, the envelope includes a Radio Frequency Identification Device (RFID) tag for local reading of the envelope's identification. Optionally, the RFID tag is a passive RFID tag. Optionally, the RFID tag is an active tag. Optionally, the RFID tag is a battery-assisted passive tag. Additionally or alternatively, the envelope includes a GPS (Global Positioning System) device for determining a location of the envelope.

In some embodiments of the present invention, the panels include paper of thickness ranging from 60 gsm (grams per square meter) to 160 gsm, for example, 60 - 90 gsm, 80 - 100 gsm, 90 - 120 gsm, 120 - 160 gsm. Optionally, the panel thickness is greater than 160 gsm. Optionally, the panels include an 80 gram wood free paper model Hadar Top produced by Israel Paper Co. Ltd, in Israel. Optionally, the panels include outer faces which are laminated. Optionally, the panels are water resistant. Optionally, the panels include a cardboard material. Additionally or alternatively, the panels include a plastic material.

In some embodiments of the present invention, the envelope may be formed from a single panel which is folded along an edge into two sections forming the first panel and the second panel, the first panel including the extension and the flap. In an exemplary embodiment, the envelope includes two edges which are sealed. Optionally, the sealed edges are along the sides of the envelope. Optionally, the sealed edges include one of the sides of the envelope and a bottom edge opposite the flap.

Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not necessarily limited in its application to the details of construction and the arrangement of the components and/or methods set forth in the following description and/or illustrated in the drawings and/or the Examples. The invention is capable of other embodiments or of being practiced or carried out in various ways.

Reference is now made to FIGURE 1A which schematically illustrates a view of an exemplary tamper-resistant envelope 100, and to FIGURES 1B and 1C which schematically illustrate side views of the tamper-resistant envelope with an open flap 106 prior to closing the envelope, and with the flap closed, respectively, according to some embodiments of the present invention.

In some embodiments, envelope 100 includes a front panel 102 (second panel) and a rear panel 104 (first panel) which are joined together along three edges by seams 103 to form a pocket 107 between the panels. The seams 103, which include two side seams and a bottom seam (opposing flap 106), are tamper-evident. Optionally, seam 103 includes perforated symbols such as letters 116 and/or geometrical shapes 118. Optionally, letters 116 and/or geometrical shapes 118 are embossed. Pocket 107 is configured for placing inside written/printed material and relatively small items which are to be sent by a sender to a receiver through a courier. The content of envelope 100 is placed inside pocket 107 through an opening 105 to the pocket, which includes a fourth edge of front panel 102 left unsealed when joining the front panel and rear panel 104 together by seams 103.

In some embodiments, rear panel 104 extends beyond opening 105 and includes flap 106 at a distal end of a rear panel extension 104A. Optionally, rear panel extension 104A includes a fold line 108 along which flap 106 is folded in a direction towards front panel 102 for adhering to the rear panel extension and to a front panel upper section 102A. Optionally, fold line 108 includes a depression along which the flap is folded. Optionally, a border of front panel upper section 102A is delimited by a flap sealing line 110 marking a desired positioning location for a distal end 106A of flap 106 when the flap is folded. Optionally, flap 106 is adapted to cover all of rear panel extension 104A and at least a portion of upper section 102A when folded. Additionally or alternatively, flap 106 is adapted to cover all of rear panel extension 104A and all of upper section 102A when folded.

In some embodiments, flap 106 includes an adhesive 114 for adhering the flap to front panel upper section 102A and rear panel extension 104A when folded. Optionally, adhering flap 106 to front panel upper section 102A and rear panel extension 104A seals opening 105 and thereby prevents access into pocket 107 through the opening. Optionally, tampering using mechanical means to gain access to opening 105, regardless from what direction, will cause noticeable damage to envelope 100. Adhesive 114 may cover a whole surface area of flap 106 between fold line 108 and distal end 106A. Optionally, adhesive 114 may cover a portion of the surface area of flap 106. Adhesive 114 may include glue, an adhesive tape, an adhesive film in accordance with the present invention, or any other type of adhesive material suitable for adhering flap 106. Adhesive 114 is a tamper-evident adhesive. Optionally, when envelope 100 is not in use, adhesive 114 is covered by a removable strip 112. Optionally, removable strip 112 is adapted to be easily removed with minimal effect on the adhesive characteristics, optionally tamper-evident characteristics, of adhesive 114. Optionally, removable strip 112 includes silicon and/or a silicon-based material allowing for easy removal of the strip.

Reference is now made to FIGURES 2A and 2B which schematically illustrate a view of a laminated inner face of an exemplary front panel 202 and an exemplary rear panel 204, respectively, in an exemplary tamper-resistant envelope 200, according to some embodiments of the present invention. Reference is also made to FIGURE 2C which schematically illustrates a side view of tamper-resistant envelope 200, according to some embodiments of the present invention. In some exemplary embodiments, envelope 200 is similar to that shown in FIGURES 1A - 1C with a difference that envelope 200 includes a front panel inner face 202C covered with a laminate film 220, a rear panel inner face 204C covered with the laminate film, and a flap 206 also covered by the laminate film on the side which is adhered. Optionally, laminate film 220 covers a whole of front panel inner face 202C (including an area of the seams) or a portion thereof. Optionally, laminate film 220 covers a whole of rear panel inner face 204C (including an area of the seams) or a portion thereof. Optionally, laminate film 220 covers only the areas of inner face 202C and 204C forming a pocket. Additionally or alternatively, laminate film 220 covers a whole of flap 206 or a portion thereof.

In some embodiments, laminate film 220 includes an optically opaque material for preventing viewing of the contents inside envelope 200 while the envelope is closed. Optionally, laminate film 220 prevents viewing of the contents when front panel 202 and/or rear panel 204 are exposed to a wetter or a wetting agent which may cause temporary transparency of the panels.

Reference is now made to FIGURE 3 which schematically illustrates a view of an exemplary tamper-resistant envelope 300 including tamper-viewing windows 321 in a flap 306, according to some embodiments of the present invention.

In some exemplary embodiments envelope 300 is similar to that shown in FIGURES 1A - 1C at 100 with a difference that envelope 300 includes windows 321 for viewing evidence of tampering with a tamper-evident adhesive 314. Optionally, envelope 300 is similar to that shown in FIGURES 2A - 2C at 200 with the difference that envelope 300 includes viewing windows 321.

In some embodiments, tamper-viewing windows 321 may include holes in flap 306 for viewing adhesive 314. Optionally, windows 321 include a film (not shown) which allows viewing adhesive 314 while protecting the adhesive from physical contact. Optionally, the film provides protection from direct contact with environmental conditions such as water, dust, and the like. Optionally, the film is a transparent film. Optionally, the film is a filter for viewing color changes (or otherwise invisible symbols) in adhesive 314 if the adhesive has been tampered with.

Reference is now made to FIGURES 4A and 4B which schematically illustrate views of an exemplary front panel 402 and rear panel 404 respectively, including exemplary markings 422 - 428, in an exemplary tamper-resistant envelope 400, according to some embodiments of the present invention.

In some exemplary embodiments, envelope 400 is similar to that shown in FIGURES 1A - 1C at 100 with a difference that envelope 400 includes markings 422 - 428. Optionally, envelope 400 is similar to that shown in FIGURES 2A - 2C at 200 with the difference that envelope 400 includes markings 422 - 428. Optionally, envelope 400 is similar to that shown in FIGURE 3 at 300 with the difference that envelope 400 includes markings 422 - 428.

Markings 422 - 428 may include information associated with directing and tracking a movement of envelope 400 while transported by the courier, for example by including a barcode marking 424, a numerator marking 422, a sender information marking 426A, a receiver information marking 426B,a general content description marking 426C (for example, a marking indicating "printed material"), and the like. Optionally, markings 422 - 428 include instructions for the sender and/or the receiver as to a use of envelope 400, for example as shown at instruction marking 428 which includes envelope sealing instructions.

Optionally markings 422 and 424 include electronic circuitry used for locating envelope 400 while in transit. Optionally, movement of envelope 400 is tracked. For example, markings 422 - 424 may include a GPS device for determining a position of envelope 400 anywhere in the world (or in specific regions of the world). Optionally, markings 422 - 424 may include an RFID tag for local reading of the envelope's numerator and/or barcode. Optionally, other markings 426A - 426C may include electronic circuitry for use with the GPS or RFID tag electronics, or for other identification and/or routing purposes. Optionally, the GPS device is removable and may be reused with other envelopes. Optionally, the GPS device is included inside the envelope (is placed inside the pocket of the envelope by the sender and may be removed by receiver, optionally for reuse).

Reference is now made to FIGURE 5 which schematically illustrates a view of an exemplary tamper-resistant envelope 500 including an exemplary electrical conductor 530 and an exemplary power source 532 for detecting tampering in the envelope, according to some embodiments of the present invention.

In some exemplary embodiments envelope 500 is similar to that shown in FIGURES 1A - 1C at 100 with a difference that envelope 500 includes electrical conductor 530 and power source 532. Optionally, envelope 500 is similar to that shown in FIGURES 2A - 2C at 200 with the difference that envelope 500 includes electrical conductor 530 and power source 532. Optionally, envelope 500 is similar to that shown in FIGURE 3 at 300 with the difference that envelope 500 includes electrical conductor 530 and power source 532. Optionally, envelope 500 is similar to that shown in FIGURES 4A and 4B at 400 with the difference that envelope 500 includes electrical conductor 530 and power source 532.

In some embodiments, electrical conductor 530, which may include an electrically conducting paint and/or electrically conducting film, extends along seams 503 in envelope 500. Optionally, when seam 503 is opened (which may include the seam being cut) an open circuit is created in conductor 530. A sensor optionally included in power source 532 senses the open circuit and causes activation of a warning. Optionally the warning is visual. Additionally or alternatively, a clock optionally included in power source 532 indicates a time and day when the open circuit was formed. Optionally, the clock is a counter activated by the open circuit and initiates counting from the moment of activation. Optionally, the warning is audible. Additionally or alternatively, electrical conductor 530 is arranged along a flap sealing line 510 and/or along an adhesive 514 in a flap 506 such that the alarm is activated when the flap is tampered with. Optionally, tampering with adhesive 514 will activate the alarm. Optionally, opening a pocket formed between a front panel 502 and a rear panel 504 will activate the alarm.

Reference is now made to FIGURE 6 which is a flow chart illustrating an exemplary method of using a tamper-resistant envelope, according to some embodiments of the present invention. In describing the method, reference is made to the exemplary embodiments shown in FIGURES 1A - 5, although it should be evident to one skilled in the art that the method may be implemented with any one of the exemplary embodiments disclosed. Furthermore, it should be evident to one skilled in the art that the method described may be varied to include more steps, less steps, a different order of steps, and is not intended to be limiting in any way.

At 600, optionally a sender prepares the tamper-resistant envelope 100 for sending by courier to a receiver at a remote location. Optionally, the sender prepares the envelope according to instruction displayed on the rear panel, for example as shown by marking 428 in rear panel 404 in FIGURE 4B. The sender opens pocket 107 and inserts the contents of what is being sent through opening 105 and into the pocket. The sender removes removable strip 112 from tamper-resistant adhesive 112 and folds flap 106 along fold line 108 in a direction towards flap sealing line 110 in front panel 102. Optionally, prior to folding flap 106, the sender may check internal tamper-evident features such as, for example, adhesive 114 to verify that there are no signs of tampering with the adhesive (change of color, warning symbols displayed, brittle composition, dissolved portions, and the like). The internal tamper-evident features are those tamper-evident features that may not be checked if envelope 100 is sealed. Optionally, the sender may verify that adhesive 114 includes symbols unique to the adhesive (verifying that the adhesive has not been replaced). Additionally or alternatively, the symbols are not visible to the naked eye. Once distal end 106A is positioned along flap sealing line 110, the sender adheres flap 106 to front panel upper section 102A and to rear panel extension 104A, sealing pocket 107. Optionally, the sender includes information as required by optional markings on the front panel, for example markings 422 - 426 as shown in FIGURE 4A. Optionally, the sender examines closed envelope 100 to verify that external tamper-evident features are in proper conditions. The external tamper-evident features includes those tamper-evident features which may be checked if envelope 100 is closed (flap 106 is sealed). This may include checking that tamper-evident seams 103 have no damaged symbols 116 and 118. Optionally, the sender examines flap windows, for example flap windows 321 as shown in FIGURE 3, to verify that there are no warning messages displayed or no change in color in the adhesive. Optionally, the sender may verify that flap 106 is properly adhered (for example, all edges of the flap and an adhering surface of the flap are flatly adhered, that is, that there are no raised portions in the flap).

At 601, the courier receives envelope 100 from the sender and records applicable data as may be required for transporting the envelope to the receiver, including envelope tracking information. Optionally, the courier may record a numerator identifying the envelope, scan a barcode, obtain data through an RFID tag in the envelope, for example, as shown at markings 422 - 426 in FIGURE 4A. Optionally, the courier may verify that the external tamper-evident features in envelope 100 show no evidence of tampering. Optionally, if envelope 100 includes external tamper-evident features which show signs which may be misinterpreted as tampering, the contents of envelope 100 is placed into a new envelope.

At 602, envelope 100 is optionally received at a central distribution center where tracking information is recorded. Optionally, the tracking information includes date and time of entering. The external tamper-evident features in envelope 100 are checked for evidence of tampering.

At 603, a determination is made as to whether or not there has been tampering with envelope 100. If there is no evidence of tampering, go to 605. Optionally, record departure information which may include date and time of exit.

At 604, envelope 100 is investigated for tampering based on the tampering evidence found on the external tampering-evident features. Optionally, the internal tampering-evident features are checked. Corroboration of tampering is investigated.

At 605, envelope 100 is optionally received at a transit station where tracking information is recorded, and which may include date and time of entering. The external tamper-evident features in envelope 100 are checked for evidence of tampering.

At 606, a determination is made as to whether or not there has been tampering with envelope 100. If there is no evidence of tampering, go to 607. Optionally, record departure information which may include date and time of exit. If there is evidence of tampering, go to 604.

At 607, envelope 100 is delivered to the receiver. Optionally, the receiver checks the external tamper-evident features of envelope 100 prior to opening of the envelope. Optionally, the receiver checks the internal tamper-evident features of the envelope following opening of flap 106.

At 608, the receiver decides whether or not there has been tampering with envelope 100, based on information derived from the external and, optionally internal, tamper-evident features. If the receiver suspects that there has been tampering the envelope is optionally left with the courier; go to 604. Optionally, the receiver signs for the envelope stating that there are signs of tampering.

At 609, the receiver receives envelope 100 following verification that the envelope was not tampered with.

FIGURE 7 is a flow chart illustrating an exemplary method of producing a tamper-resistant envelope, according to some embodiments of the present invention. In describing the method, reference is made to the exemplary embodiment shown in FIGURES 1A - 5, although it should be evident to one skilled in the art that the method may be implemented with any one of the exemplary embodiments disclosed. Furthermore, it should be evident to one skilled in the art that the method described may be varied to include more steps, less steps, a different order of steps, and is not intended to be limiting in any way.

At 700, optionally sheets from which the front panel and the rear panel are prepared are laminated with an optically opaque laminated film; for example laminated film 220 in FIGURES 2A and 2B.

At 701, optionally the laminated sheets are cut to form the front panel and the rear panel, the laminated film on an inner face of the front panel and on an inner face of the rear panel; for example front panel 202 with laminated film 220 on inner face 202C as shown in FIGURE 2B, and rear panel 204 with laminated film 220 on inner face 204C as shown in FIGURE 2A. Optionally, a bubble wrap liner is attached to inner faces 202C and 204C of front panel 202 and rear panel 204, respectively.

At 702, optionally form the tamper-resistant envelope by joining the front panel to the rear panel along three seams, forming a pocket between the panels; for example, envelope 100 formed by joining front panel 102 with rear panel 104 along seams 103, with pocket 107 formed between the panels.

At 703, optionally prepare the tamper-evident seam by perforating or embossing symbols in the seams; for example, symbols 116 and 118 in seams 103 as shown in FIGURE 1A.

At 704, optionally prepare the tamper-evident viewing windows in the flap; for example, windows 321 in flap 306 as shown in FIGURE 3.

At 705, optionally apply tamper-resistant adhesive to the flap and cover the adhesive with a removable strip so as to avoid inadvertent adhering of the adhesive or inadvertent tampering with the adhesive; for example, adhesive 114 applied to flap 106 and covering a substantial area of the flap between fold line 108 and distal end 106A, and removable strip 112 placed over that adhesive, as shown in FIGURE 1A.

At 706, optionally apply markings to the envelope panels; for example flap sealing line 110 on front panel 102 shown in FIGURE 1A, and markings 422 - 426 on front panel 402 and markings 428 on rear panel 404 as shown in FIGURES 4A and 4B.

The terms "comprises", "comprising", "includes", "including", "having" and their conjugates mean "including but not limited to". This term encompasses the terms "consisting of" and "consisting essentially of".

The phrase "consisting essentially of" means that the composition or method may include additional ingredients and/or steps, but only if the additional ingredients and/or steps do not materially alter the basic and novel characteristics of the claimed composition or method.

As used herein, the singular form "a", "an" and "the" include plural references unless the context clearly dictates otherwise. For example, the term "a compound" or "at least one compound" may include a plurality of compounds, including mixtures thereof.

The word "exemplary" is used herein to mean "serving as an example, instance or illustration". Any embodiment described as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments and/or to exclude the incorporation of features from other embodiments.

The word "optionally" is used herein to mean "is provided in some embodiments and not provided in other embodiments". Any particular embodiment of the invention may include a plurality of "optional" features unless such features conflict.

Throughout this application, various embodiments of this invention may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within that range, for example, 1, 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.

Whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range. The phrases "ranging/ranges between" a first indicate number and a second indicate number and "ranging/ranges from" a first indicate number "to" a second indicate number are used herein interchangeably and are meant to include the first and second indicated numbers and all the fractional and integral numerals therebetween.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination or as suitable in any other described embodiment of the invention. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations, whereby the scope of the invention is defined by the appended claims.