EP3705306A1

EP3705306A1 - A method for manufacturing a laminated paper product with integrated electronics

Info

Publication number: EP3705306A1
Application number: EP19160960.1A
Authority: EP
Inventors: Marco Dehouwer; Jasper van Deun; Lander Verboven
Original assignee: Cartamundi Turnhout NV
Current assignee: Cartamundi Turnhout NV
Priority date: 2019-03-06
Filing date: 2019-03-06
Publication date: 2020-09-09

Abstract

A method for manufacturing a laminated paper product (1) with integrated electronics, comprising:- providing a paper sheet (10);- printing image pairs (100) on a printing surface (11) of said paper sheet (10);- die cutting strips (110) from said paper sheet (10), thereby obtaining strips (110) each comprising two flaps (120), a first flap (121) comprising a set of images (101) from said image pairs (100) and a second flap (122) comprising the corresponding set of images (102) from said image pairs (100);- providing planar electronics (20) on an opposite surface (12) to said printing surface (11);- applying adhesive (30) on an opposite surface (12) to said printing surface (11);- folding each of said strips (110) along a respective fold line (13);- applying pressure; and- punching said laminated paper product (1).

Description

Field of the Invention

The present invention generally relates to the manufacturing of a laminated paper product with integrated electronics. More particularly, the present invention concerns a process for improving the front to back registration of a laminated paper product comprising integrated electronics.

Background of the Invention

When integrating electronics in paper products such as cards, playing cards, tickets, leaflets, etc.., there is a general desire to maintain the properties of a traditional paper card: the paper product with integrated electronics must be planar with homogeneous thickness and the surface of the paper product must be printable with high quality images.
The desire to produce paper cards with integrated electronics and uniform thickness has been expressed in several prior art documents. European patent application EP3269558 entitled "A manufacturing process for a laminated paper product" for instance describes the manufacturing of a laminated paper product with integrated electronics. The method described in EP3269558 comprises the steps of printing and cutting a first paper, printing and cutting a second paper, and forming a paper product by providing planar electronics between the first paper and the second paper when the first paper and the second paper are overlaid on top of each other and glued to each other.
A drawback of the manufacturing method described in EP3269558 is that the pre-cut second paper must be very precisely and individually aligned with respect to the pre-cut first paper when forming the paper product such that the front to back registration of the final paper product is guaranteed. If the second paper is not suitably aligned with respect to the first paper, for example if the second paper is rotated with respect to the first paper, the front to back registration of the final paper product is poor. The alignment operation must also be repeated for all the second papers and the corresponding first papers. This is a very sensitive alignment which must be accurately controlled to maximize the quality of the final paper product. The manufacturing method described in EP3269558 is therefore too slow to be developed at large scale. Additionally, in EP3269558 , after overlaying the second paper on top of the planar electronics and the first paper, a heated roll applies heat and pressure to the three aligned layers to active the glue. There is a risk that the planar electronics are damaged by the temperature elevation and/or by the pressure applied on the three overlaid layers.
European Patent Application EP0858061 entitled "A safety label and a device for its manufacture" describes a method for manufacturing labels with integrated electronics and uniform thickness. The manufacturing method of EP0858061 is developed to produce labels comprising a radio-frequency tag fitted between two sheets of cardboard. A continuous roll of printed cardboard is provided with the front and the back of the label such that they form a single body. A labelling machine positions the radio-frequency tags over the non-printed side of the printed cardboard. Two rollers perpendicular to the advance of the continuous printed cardboard cause the folding of the printed cardboard along a longitudinal line such that both halves of the continuous printed cardboard are overlaid on top of each other and glued together.
The manufacturing method described in EP0858061 is developed for cardboard with a much smaller substance than those used in manufacture of conventional labels, as described on page 3, lines 27-31 of EP0858061 . A drawback of this manufacturing method is therefore that it requires working with rolls of flexible substrate which can easily be folded. The manufacturing method of EP0858061 is not compatible with substrates and paper sheets which are thicker and more rigid than cardboard for the manufacturing of labels, such as for example substrates and paper sheets used to manufacture cards or playing cards or tickets, PVC cards, etc.. It remains very challenging to feed a roll of continuous thicker substrate to the two rollers of EP0858061 and to fold the continuous thicker and rigid substrate along a longitudinal line while ensuring a satisfying front to back registration of the final paper product. Additionally, the manufactured labels of EP0858061 must be submitted to pressure rollers which press down the two halves of the labels together and which submit the manufactured labels to an elevation in temperature. The applied heat and pressure risk damaging the radio-frequency tags and there is a risk the tags do not function properly anymore.

Summary of the Invention

It is an objective of the present invention to disclose a process and a system to manufacture laminated paper products comprising integrated electronics that overcome the above identified shortcomings of existing solutions. More particularly, it is an objective to disclose a manufacturing process and a manufacturing system which allow production of laminated paper products comprising integrated electronics at large scale and wherein the laminated paper products demonstrate improved front to back registration.
According to a first aspect of the present invention, the above defined objectives are realized by a method for manufacturing a laminated paper product with integrated electronics, wherein the method comprises the steps of:

providing a paper sheet;
printing image pairs on a printing surface of the paper sheet;
die cutting strips from the paper sheet, thereby obtaining strips each comprising two flaps, a first flap comprising a set of images from the image pairs and a second flap comprising the corresponding set of images from the image pairs;
providing planar electronics on an opposite surface to the printing surface of at least one of the flaps;
applying adhesive on an opposite surface to the printing surface of at least one of the flaps;
folding each of the strips along a respective fold line, thereby overlaying the flaps onto each other and obtaining overlaid flaps;
applying pressure on the overlaid flaps;
punching the laminated paper product out of the overlaid flaps.

The manufacturing method according to the present invention results in an improved front to back registration of laminated paper products. Indeed, thanks to the manufacturing process according to the present invention, a laminated paper product is produced with very precise alignment of the two flaps with respect to each other when the two flaps are overlaid on top of each other by folding a strip along its fold line. The use of a strip comprising both the front and the back of the laminated paper product lowers the risk of a possible misalignment of the front with respect to the back of the laminated paper product due to a rotation of the paper sheet when overlaying the front on top of the back of the laminated paper product when the front and the back of the laminated paper product are manufactured from a paper sheet which would comprise several strips. The laminated paper product has a uniform thickness of at most 7 millimeters, preferably at most 6 millimeters, enabling to maintain the tactile properties of existing paper cards or cardboard cards that have no electronics integrated. Additionally, with the manufacturing method according to the present invention, both flaps overlaid to form the laminated paper product are printed next to each other on the paper sheet. In other words, both flaps are printed so close to each other on the paper sheet that both flaps have similar thicknesses and similar fiber structure from the paper sheet as both flaps are printed from the same paper sheet. This way, there is very little deviation in the thickness and fiber structure of both flaps when both flaps are overlaid to form the laminated paper product. The laminated paper product is therefore well balanced, and its thickness is uniform over the whole product. Additionally, the image pairs printed on both flaps will be printed on similar fiber structures. The printing display and the printing quality of both sets of image pairs on the two flaps of a laminated paper product manufactured according to the present invention will be more similar than when the laminated paper product is manufactured according to a manufacturing process known from the prior art by overlaying and gluing the front and the back of a laminated paper product on top of each other, wherein the front and the back were printed on two separate strips formed on two different paper sheets that are then overlaid and glued together. Additionally, both flaps fabricated from a strip will demonstrate the same mechanical resistance and the same folding behavior as both flaps are manufactured from the same paper sheet. For example, in presence of elevated humidity in the environment of the laminated paper product, both flaps manufactured from the same paper sheet will deform the same way. This will avoid creating a warping or bending effect that is caused by humidity change over time of a stack of playing cards.
Another technical advantage of the method according to the present invention is its speed and its adaptability for large scale production. Indeed, with the method according to the present invention, there is no need to individually and separately align the two flaps with respect to each other when the flaps are overlaid. There is no need to prevent misalignment by a slight rotation from one flap with respect to the other flap. For example, the printing speed with the method according to the present invention is typically printing 8000 paper sheets per hour. For example, the die cutting speed with the method according to the present invention is typically die cutting 3000 paper sheets per hour. For example, the strip folding speed with the method according to the present invention is folding 5000 strips per hour.
Thanks to the use of die cut strips of paper sheets, it is easier with the manufacturing process according to the present invention to form laminated paper products from a thicker and/or a denser paper sheet than with manufacturing methods known from the prior art. The substrates used in methods known from the prior art must be thin enough to be continuously and simultaneously longitudinally stretched and folded by rollers when overlaying the front and the back of a laminated paper product on top of each other. For example, it remains very challenging to produce PVC cards with the method described in EP0858061 . On the contrary, with the manufacturing method according to the present invention, pre-cutting strips of the substrate or of the paper sheet and overlaying both flaps of each strip on top of each other allows using thicker and more rigid substrates and/or thicker and more rigid paper sheets to form laminated products, without rotation of one flap with respect to the other and while guaranteeing a good front to back registration of the final laminated paper product. Optionally, another technical advantage when working with die cut strips is the maximization of the use of the surface of the paper sheet for the manufacturing of the laminated paper product. The strips can be die cut so as to minimize a margin with respect to the dimensions of the paper sheet, thereby reducing waste of paper sheet.
The paper sheet according to the present invention for example comprises a longitudinal direction along which one or more of the respective fold lines of the strips are extending. In other words, one or more image pairs are printed on the printing surface of the paper sheet such that a respective fold line separates the image pairs into two sets and such that the respective fold line extends along the longitudinal direction of the paper sheet. Alternatively, the paper sheet for example comprises a longitudinal direction, and one or more of the respective fold lines of the strips are extending along a traverse direction traverse to the longitudinal direction of the paper sheet. In other words, one or more image pairs are printed on the printing surface of the paper sheet such that a respective fold line separates the image pairs into two sets and such that the respective fold line extends along the traverse direction of the paper sheet.
The adhesive for example becomes active when applying heat and/or pressure. The adhesive may be provided before or after the printing and cutting.
The risk for damaging the planar electronics is minimized through the print and cut first, assemble later concept. Additionally, the planar electronics is not submitted to an elevation of temperature through heating of the overlaid flaps, which guarantees the integrity of the planar electronics. The risk of damaging the planar electronics during manufacturing the laminated paper product is therefore minimized with respect to methods know from the prior art which require submitting the planar electronics to an elevated temperature to cure an adhesive provided between the front and the back of the paper product. Alternatively, the planar electronics is submitted to a slight elevation of temperature when heating the overlaid flaps and applying minimal pressure on them in order to cure the adhesive. In this case, the temperature is chosen adequately as to guarantee the performance of the planar electronics is not jeopardized. For example, the overlaid flaps are laminated by reactivating the adhesive through heat and minimal pressure applied by for example a heated roll system. The temperature of this heated roll system is preferably kept below 120°C to avoid damaging the ink printed on the paper sheet and the planar electronics in the laminated paper product. Additionally, the lamination process is applied as a last step. No printing of the laminated product must be done afterwards, further reducing the risk for damaging the planar electronics and consequently improving the overall yield of the produced laminated paper product with integrated electronics. Also, the overlaid flaps undergo limited pressure in order to securely glue the flaps together while preserving the physical integrity of the planar electronics integrated in the laminated paper product. For example, the overlaid flaps are submitted to a pressure of maximum 4 bar distributed over one or more rolls.
Planar electronics in the context of the present invention for example comprise a RFID inlay. A RFID chip is typically for example 60 µm thick, and the inlay on the RFID chip itself is usually for example 100 µm thick. Alternatively, the planar electronics comprise printed electronics. Alternatively, the planar electronics according to the present invention comprise one or more Near Field Communication chips, also referred to as NFC chips.
According to an optional aspect of the invention, the paper sheet has a thickness comprised between 100 micrometers and 3000 micrometers.
For example, the paper sheet preferably has a thickness of 170 micrometers Alternatively, the paper sheet preferable has a thickness of 300 micrometers.
According to an optional aspect of the invention, the paper sheet has a paper weight comprised between 80 and 3000 grams per square meter.
For example, the paper sheet preferably has a paper weight of 175 grams per square meter. Alternatively, the paper sheet preferable has a paper weight of 275 grams per square meter.
According to an optional aspect of the invention, printing image pairs corresponds to printing a set of images from the image pairs on one of the flaps and to printing the set of corresponding images from the image pairs on the other flap such that each of the image pairs is divided by the respective fold line.
This way, the front and the back of the laminated paper product are printed on the same printing surface of the same paper sheet, only a few centimeters away from each other on the same printing surface. In other words, each flap of the pre-cut strips comprises half of the image pairs printed on the strips.
According to an optional aspect of the invention, providing planar electronics on the opposite surface of at least one of the flaps corresponds to aligning the planar electronics on the opposite surface of at least one of the flaps such that the planar electronics coincide with the images on the printing surface of the respective flap.
The planar electronics are aligned with respect to the images on the printing surface of the respective flap. This way, the planar electronics are encapsulated in the adhesive between the two flaps on the laminated paper product. In other words, the planar electronics is surrounded on all sides by adhesive when the two flaps are overlaid on top of each other. This protects the planar electronics from the exterior environment, thereby guaranteeing its integrity.
According to an optional aspect of the invention, each of the image pairs comprises a front side image of a laminated paper product and a corresponding back side image of a laminated paper product.
This way, the front side image and the back side image are overlaid on top of each other when both flaps of a strip are overlaid such that both the front side image and the back side image of the laminated paper product face outwards. For example, the laminated paper product is a playing card and each of the image pairs comprises a front side image of a playing card and a corresponding back side image of a playing card. Alternatively, the laminated paper product is a card, a ticket, a leaflet, etc. and each of the image pairs comprises a front side image of respectively a card, a ticket, a leaflet, etc..
According to an optional aspect of the invention, folding each of the strips along the respective fold line corresponds to overlaying the front side images and the corresponding back side images onto each other, thereby forming pairs of images overlaid onto each other.
According to an optional aspect of the invention, punching the laminated paper product out of the overlaid flaps corresponds to punching a pair of images overlaid onto each other out of the overlaid flaps, thereby obtaining the laminated paper product.
The laminated paper product is for example a playing card and punching the laminated paper product out of the overlaid flaps corresponds to punching a pair of playing card images overlaid onto each other out of the overlaid flaps, thereby obtaining the playing card. Alternatively, the laminated paper product is for example a ticket and punching the laminated paper product out of the overlaid flaps corresponds to punching a pair of playing card images overlaid onto each other out of the overlaid flaps, thereby obtaining the ticket.
Punching the laminated paper product out of the overlaid flaps allows a very precise cut of the laminated paper product out of the overlaid flaps. The cut edges along the periphery of the laminated paper product are straight and clean. The cut edge of one flap is aligned with respect the cut edge of the corresponding other flap along a traverse direction to the planed formed by the laminated paper product. Alternatively, the method further comprises trimming edges of the laminated paper product after punching the laminated paper product out of the overlaid flaps. Alternatively, the edges of the laminated paper product produced through the method are trimmed with a cutter after the lamination process when the card edges are too rough.
According to an optional aspect of the invention, the method further comprises the step of printing opacifying images on the opposite surface of the paper sheet before die cutting the strips from the paper sheet.
This way, the opacity of the printing surface of the paper sheet is improved. In other words, the planar electronics cannot be seen through the front side image and the back side image of the laminated paper product. For example, the opacifying images are black images printed on the opposite surface of the paper sheet. Alternatively, the method further comprises the step of applying colored adhesive on the opposite surface of the flaps in order to improve the opacity of the printing surface of the paper sheet.
According to an optional aspect of the invention, the method further comprises the step of aligning the opacifying images with respect to the images such that the opacifying images coincide with the images on the printing surface of the respective flap.
According to an optional aspect of the invention, applying the adhesive on the opposite surface of at least one of the flaps corresponds to applying hot melt glue on the opposite surface of at least one of said flaps.
This way, both flaps are securely fixed to each other when overlaid on top of each other, thereby ensuring the planar electronics does not detach from the opposite surface of at least one of the flaps. Alternatively, any other type of suitable glue may be applied to the opposite surface of at least one of the flaps.
According to an optional aspect of the invention, applying the adhesive on the opposite surface of at least one of the flaps corresponds to applying hot melt glue on the opposite surface of both flaps.
This way, both flaps are securely fixed to each other when overlaid on top of each other, thereby ensuring the planar electronics does not detach from the opposite surface of the flaps. Alternatively, any other type of suitable glue may be applied to the opposite surface of at least one of the flaps. This way, the laminated paper product demonstrates flat surfaces as the hot melt glue planarizes the opposite surface of the laminated paper product when both flaps are overlaid on top of each other. When applying adhesive on the planar electronics and on both flaps of the strips, a very good adhesion of the adhesive to the paper sheet and to the planar electronics is achieved at the processing temperature. Additionally, when folding the flaps on top of each other, an adhesive on one flap comes in contact with another adhesive on the other flap, thereby creating a very strong bond between the two flaps. Preferably, the faster the strip is folded, the better the adhesion between the two flaps.
Alternatively, the hot melt glue can be cured through passive cooling. The overlaid flaps are laminated by reactivating the adhesive, for example the hot melt glue, through heat and pressure applied by for example a heated roll system. The temperature of this heated roll system is preferably kept below 120°C to avoid damaging the ink printed on the paper sheet and the planar electronics in the laminated paper product. The hot melt glue is cured afterwards through passive cooling.
According to a second aspect of the invention, there is provided a system for manufacturing a laminated paper product with integrated electronics, wherein the system comprises:

a paper sheet providing unit adapted to provide a paper sheet;
a printing station adapted to print image pairs on a printing surface of the paper sheet;
a die cutting unit adapted to die cut strips from the paper sheet, thereby obtaining strips each comprising two flaps, a first flap comprising a set of images from the image pairs and a second flap comprising the corresponding set of images from the image pairs;
a planar electronics providing unit adapted to provide planar electronics on an opposite surface to the printing surface of at least one of the flaps;
a gluing station adapted to apply adhesive on an opposite surface to the printing surface of at least one of the flaps;
a folding station adapted to fold each of the strips along a respective fold line, thereby overlaying the flaps onto each other and obtaining overlaid flaps;
a pressure applying unit adapted to apply pressure on the overlaid flaps; and
a punching unit adapted to punch the laminated paper product out of the overlaid flaps.

The system according to the present invention results in an improved front to back registration of laminated paper products. Indeed, thanks to the system according to the present invention, a laminated paper product is produced with very precise alignment of the two flaps with respect to each other when the two flaps are overlaid on top of each other by folding a strip along its fold line. The use of a strip comprising both the front and the back of the laminated paper product lowers the risk of a possible misalignment of the front with respect to the back of the laminated paper product due to a rotation of the paper sheet when overlaying the front on top of the back of the laminated paper product when the front and the back of the laminated paper product are manufactured from a paper sheet which would comprise several trips. The laminated paper product has a uniform thickness of at most 7 millimeters, preferably at most 6 millimeters, enabling to maintain the tactile properties of existing paper cards or cardboard cards that have no electronics integrated. Additionally, with the system according to the present invention, both flaps overlaid to form the laminated paper product are printed next to each other on the paper sheet. In other words, both flaps are printed so close to each other on the paper sheet that both flaps have similar thicknesses and similar fiber structure from the paper sheet as both flaps are printed from the same paper sheet. This way, there is very little deviation in the thickness and fiber structure of both flaps when both flaps are overlaid to form the laminated paper product. The laminated paper product is therefore well balanced, and its thickness is uniform over the whole product. Additionally, the image pairs printed on both flaps will be printed on similar fiber structures. The printing display and the printing quality of both sets of image pairs on the two flaps of a laminated paper product manufactured with a system according to the present invention will be more similar than when the laminated paper product is manufactured with a system known from the prior art by overlaying and gluing the front and the back of a laminated paper product on top of each other, wherein the front and the back were printed on two separate strips formed on two different paper sheets that are then overlaid and glued together. Additionally, both flaps fabricated from a strip will demonstrate the same mechanical resistance and the same folding behavior as both flaps are manufactured from the same paper sheet. For example, in presence of elevated humidity in the environment of the laminated paper product, both flaps manufactured from the same paper sheet will deform the same way.
Thanks to the use of die cut strips of paper sheets, it is easier with the system according to the present invention to form laminated paper products from a thicker and/or a denser paper sheet than with system known from the prior art. The substrates used in methods known from the prior art must be thin enough to be continuously and simultaneously longitudinally stretched and folded when overlaying the front and the back of a laminated paper product on top of each other. On the contrary, with the system according to the present invention, pre-cutting strips of the substrate or of the paper sheet and overlaying both flaps of each strip on top of each other allows using thicker and more rigid substrates and/or thicker and more rigid paper sheets to form laminated products.
The paper sheet according to the present invention for example comprises a longitudinal direction along which one or more of the respective fold lines of the strips are extending. In other words, one or more image pairs are printed on the printing surface of the paper sheet such that a respective fold line separates the image pairs into two sets and such that the respective fold line extends along the longitudinal direction of the paper sheet. Alternatively, the paper sheet for example comprises a longitudinal direction, and one or more of the respective fold lines of the strips are extending along a traverse direction traverse to the longitudinal direction of the paper sheet. In other words, one or more image pairs are printed on the printing surface of the paper sheet such that a respective fold line separates the image pairs into two sets and such that the respective fold line extends along the traverse direction of the paper sheet.
The adhesive for example becomes active when applying heat and/or pressure. The adhesive may be provided before or after the printing and cutting.
The risk for damaging the planar electronics is minimized through the print and cut first, assemble later concept. Additionally, the planar electronics is not submitted to an elevation of temperature through heating of the overlaid flaps, which guarantees the integrity of the planar electronics. The risk of damaging the planar electronics during manufacturing the laminated paper product is therefore minimized with respect to methods know from the prior art which require submitting the planar electronics to an elevated temperature to cure an adhesive provided between the front and the back of the paper product. Alternatively, the planar electronics is submitted to a slight elevation of temperature when heating the overlaid flaps and applying pressure on them in order to cure the adhesive. In this case, the temperature is chosen adequately as to guarantee the performance of the planar electronics is not jeopardized. For example, the overlaid flaps are laminated by reactivating the adhesive through heat and pressure applied by for example a heated roll system. The temperature of this heated roll system is preferably kept below 120°C to avoid damaging the ink printed on the paper sheet and the planar electronics in the laminated paper product. Additionally, the expensive lamination process is applied as a last step. No cutting or printing of the laminated product must be done afterwards, further reducing the risk for damaging the planar electronics and consequently improving the overall quality of the produced laminated paper product with integrated electronics. Also, the overlaid flaps undergo limited pressure in order to securely glue the flaps together while preserving the physical integrity of the planar electronics integrated in the laminated paper product. For example, the overlaid flaps are submitted to a pressure of maximum 4 bar in distributed over one or more rolls.
Planar electronics in the context of the present invention is for example a RFID inlay. A RFID chip is typically for example 60 µm thick, and the inlay on the RFID chip itself is usually for example 100 µm thick. Alternatively, the planar electronics are printed electronics.

Brief Description of the Drawings

Fig. 1A and 1B schematically illustrates an embodiment of a system according to the present invention.
Fig. 2 schematically illustrates an embodiment of a paper sheet according to the present invention.
Fig. 3 schematically illustrates an embodiment of a strip according to the present invention.
Figs. 4A and 4B schematically illustrate an embodiment of an opposite surface of a strip according to the present invention.
Figs. 5A, 5B and 5C schematically illustrate an embodiment of overlaid flaps and laminated paper products punched out of these overlaid flaps according to the present invention.
Fig. 6 schematically illustrates an embodiment of the steps of the method according to the present invention.

Detailed Description of Embodiment(s)

According to an embodiment shown in Fig. 1A, a system 2 for manufacturing a laminated paper product 1 with integrated electronics comprises a paper sheet providing unit adapted to provide a paper sheet 10, a printing station adapted to print image pairs on a printing surface of the paper sheet 10 and a die cutting unit adapted to die cut strips 110 from the paper sheet 10, thereby obtaining strips 110 each comprising two flaps 120, a first flap 121 comprising a set of images from the image pairs and a second flap 122 comprising the corresponding set of images from the image pairs. The system 2 further comprises a strip feeding unit 203 adapted to feed strips 110 into the lamination line. The system 2 further comprises a planar electronics providing unit 204 adapted to provide planar electronics 20 on an opposite surface to the printing surface of at least one of the flaps 121;122. The system 2 further comprises a gluing station 205 adapted to apply adhesive 30 on an opposite surface to the printing surface of at least one of the flaps 121;122. The system 2 further comprises a folding station 206 adapted to fold each of the strips 110 along a respective fold line 13, thereby overlaying the flaps 121;122 onto each other and obtaining overlaid flaps 130. The system 2 further comprises a pressure applying unit 207 adapted to apply minimal pressure and optionally heat on the overlaid flaps 130. The overlaid flaps 130 are then stored at the following stage 209 to be processed again in step 210 independent from the previous processing steps. According to an embodiment shown in Fig. 1B, the system 2 further comprises a punching unit 208 adapted to punch the laminated paper product 1 out of the overlaid flaps 130. According to the present invention, the step of punching the laminated paper product 1 out of the overlaid flaps 130 is performed on a different processing line than the other method steps.
According to an embodiment shown in Fig. 2, a paper sheet 10 according to the present invention comprises a printing surface 11. The paper sheet 10 has a thickness comprised between 100 micrometres and 3000 micrometres. The paper sheet 10 has a paper weight comprised between 80 and 3000 grams per square metre. One or more image pairs 100 are printed on the printing surface 11 of the paper sheet 10. For example, on Fig. 2, eighteen image pairs 100 are printed on the printing surface 11 of the paper sheet 10. According to an alternative embodiment, one or more image pairs 100 are printed on the printing surface 11 of the paper sheet 10, for example tens of images pairs 100, for example hundreds of image pairs 100. The image pairs 100 can be identical to each other. According to an alternative embodiment, the image pairs 100 can be different. Strips 110 are defined on the paper sheet 10. For example, on Fig. 2, three strips 110 of each six image pairs 100 are printed on the printing surface 11 of the paper sheet 10. Each of the strips 110 comprises two flaps 120, a first flap 121 comprising a set of images 101 from the image pairs 100 and a second flap 122 comprising a corresponding set of images 102 from the image pairs 100. The set of images 101 and the set of images 102 are different from each other. According to an alternative embodiment, the set of images 101 and the set of images 102 are identical. Each of the image pairs 100 comprises a front side image 103 of a laminated paper product and a corresponding back side image 104 of the laminated paper product. According to an alternative embodiment, one or more strips 110 are printed on the printing surface 11 of the paper sheet 10. The image pairs 100 are printed such that the image pairs 100 are divided by a respective fold line 13. Opacifying images are printed on an opposite surface of the paper sheet 10 opposite to the printing surface 11 of the paper sheet 10 before die cutting the strips 110 from the paper sheet 10.
According to an embodiment shown in Fig. 3, one strip 110 is die cut from the paper sheet 10. Components having identical reference numbers to components of Fig. 1 or 2 fulfil the same function. The paper sheet 10 according to the present invention comprises a printing surface 11 and an opposite surface 12 opposite to the printing surface 11. The paper sheet 10 has a thickness comprised between 100 micrometres and 3000 micrometres. The paper sheet 10 has a paper weight comprised between 80 and 3000 grams per square metre. One or more image pairs 100 are printed on the strip 110. For example, six image pairs 100 are printed on the printing surface 11 of the paper sheet 10 for this strip 110. According to an alternative embodiment, one or more image pairs 100 are printed on the printing surface 11 of the paper sheet 10 for each strip 110, for example tens of images pairs 100, for example hundreds of image pairs 100. The image pairs 100 can be identical to each other. According to an alternative embodiment, the image pairs 100 can be different. The strip 110 comprises two flaps 120, a first flap 121 comprising a set of images 101 from the image pairs 100 and a second flap 122 comprising a corresponding set of images 102 from the image pairs 100. The set of images 101 and the set of images 102 are different from each other. According to an alternative embodiment, the set of images 101 and the set of images 102 are identical. The image pairs 100 are printed such that the image pairs 100 are divided by a respective fold line 13. Opacifying images 140 are printed on the opposite surface 12 of the paper sheet 10 before die cutting the strips 110 from the paper sheet 10. The opacifying images 140 are aligned with respect to the images 101;102 such that the opacifying images 140 coincide with the images 101;102 on the printing surface 11 of the respective flaps 121;122.
According to an embodiment shown in Fig. 4A, one strip 110 is die cut from the paper sheet 10. Components having identical reference numbers to components of Fig. 1 or 2 or 3 fulfil the same function. The paper sheet 10 according to the present invention comprises an opposite surface 12. The paper sheet 10 has a thickness comprised between 100 micrometres and 3000 micrometres. The paper sheet 10 has a paper weight comprised between 80 and 3000 grams per square metre. The strip 110 comprises two flaps 120. Opacifying images 140 are printed on the opposite surface 12 of the paper sheet 10 before die cutting the strips 110 from the paper sheet 10. The opacifying images 140 are printed such that they are divided by a respective fold line 13. Planar electronics 20 are provided on the opposite surface 12 of at least one of the flaps 121;122. According to an alternative embodiment, planar electronics 20 are provided on the opposite surface 12 of both flaps 121;122. Planar electronics 20 are provided for each of the image pairs printed on the printing surface of the paper sheet. According to an alternative embodiment, planar electronics 20 are provided for one or more of the image pairs printed on the printing surface of the paper sheet. Planar electronics 20 are aligned on the opposite surface 12 of at least one of the flaps 120 such that the planar electronics 20 coincide with the images on the printing surface of the respective flap 121;122. As visible on Fig. 4B, adhesive 30 is applied on the opposite surface 12 of at least one of the flaps 121;122. According to an alternative embodiment, adhesive 30 is applied on both opposite surfaces 12 of both flaps 120. The adhesive 30 is for example hot melt glue.
According to an embodiment shown in Fig. 5A, one strip 110 is die cut from the paper sheet 10. Components having identical reference numbers to components of Fig. 1 or 2 or 3 or 4A or 4B fulfil the same function. The paper sheet 10 according to the present invention comprises an opposite surface 12. The paper sheet 10 has a thickness comprised between 100 micrometres and 3000 micrometres. The paper sheet 10 has a paper weight comprised between 80 and 3000 grams per square metre. The strip 110 comprises two flaps 120. Opacifying images 140 are printed on the opposite surface 12 of the paper sheet 10 before die cutting the strips 110 from the paper sheet 10. The opacifying images 140 are printed such that they are divided by a respective fold line 13. Planar electronics 20 are provided on the opposite surface 12 of at least one of the flaps 121;122. According to an alternative embodiment, planar electronics 20 are provided on the opposite surface 12 of both flaps 121;122. Planar electronics 20 are provided for each of the image pairs printed on the printing surface of the paper sheet. According to an alternative embodiment, planar electronics 20 are provided for one or more of the image pairs printed on the printing surface of the paper sheet. Adhesive 30 is applied on the opposite surface 12 of at least one of the flaps 121;122. According to an alternative embodiment, adhesive 30 is applied on both opposite surfaces 12 of both flaps 120. The adhesive 30 is for example hot melt glue. As visible on Fig. 5B, the strip 110 is folded along the fold line 13, thereby overlaying the flaps 120 onto each other and obtaining overlaid flaps 130. Overlaying flaps 120 corresponds to overlaying front side images 103 and back side images 104 onto each other, thereby forming pairs of images overlaid onto each other. Pressure is applied on the overlaid flaps 130. Optionally, heat is applied to the overlaid flaps 130. Finally, as visible on Fig. 5C, six laminated paper products 1 are punched out of the overlaid flaps 130.
Fig. 6 schematically illustrates an embodiment of the steps of the method according to the present invention. In step 601, a paper sheet 10 is provided. In step 602, image pairs 100 are printed on a printing surface 11 of the paper sheet 10. In step 603, strips 110 are die cut from the paper sheet 10, thereby obtaining strips 110 each comprising two flaps 120, a first flap 121 comprising a set of images 101 from the image pairs 100 and a second flap 122 comprising the corresponding set of images 102 from the image pairs 100. In step 604, planar electronics 20 are provided on an opposite surface 12 to the printing surface 11 of at least one of the flaps 120. In step 605, adhesive 30 is applied on an opposite surface 12 to the printing surface 11 of at least one of the flaps 120. Each of the strips 110 are folded in step 606 along a respective fold line 13, thereby overlaying the flaps 120 onto each other and obtaining overlaid flaps 130. In step 607, pressure is applied on the overlaid flaps 130. And finally, in step 608, a laminated paper product 1 is punched out of the overlaid flaps 130.
Although the present invention has been illustrated by reference to specific embodiments, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied with various changes and modifications without departing from the scope thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. In other words, it is contemplated to cover any and all modifications, variations or equivalents that fall within the scope of the basic underlying principles and whose essential attributes are claimed in this patent application. It will furthermore be understood by the reader of this patent application that the words "comprising" or "comprise" do not exclude other elements or steps, that the words "a" or "an" do not exclude a plurality, and that a single element, such as a computer system, a processor, or another integrated unit may fulfil the functions of several means recited in the claims. Any reference signs in the claims shall not be construed as limiting the respective claims concerned. The terms "first", "second", third", "a", "b", "c", and the like, when used in the description or in the claims are introduced to distinguish between similar elements or steps and are not necessarily describing a sequential or chronological order. Similarly, the terms "top", "bottom", "over", "under", and the like are introduced for descriptive purposes and not necessarily to denote relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and embodiments of the invention are capable of operating according to the present invention in other sequences, or in orientations different from the one(s) described or illustrated above.

Claims

A method for manufacturing a laminated paper product (1) with integrated electronics, wherein said method comprises the steps of:
- providing a paper sheet (10);

- printing image pairs (100) on a printing surface (11) of said paper sheet (10);

- die cutting strips (110) from said paper sheet (10), thereby obtaining strips (110) each comprising two flaps (120), a first flap (121) comprising a set of images (101) from said image pairs (100) and a second flap (122) comprising the corresponding set of images (102) from said image pairs (100);

- providing planar electronics (20) on an opposite surface (12) to said printing surface (11) of at least one of said flaps (120);

- applying adhesive (30) on an opposite surface (12) to said printing surface (11) of at least one of said flaps (120);

- folding each of said strips (110) along a respective fold line (13), thereby overlaying said flaps (120) onto each other and obtaining overlaid flaps (130);

- applying pressure on said overlaid flaps (130); and

- punching said laminated paper product (1) out of said overlaid flaps (130).
A method according to claim 1, wherein said paper sheet (10) has a thickness comprised between 100 micrometers and 3000 micrometers.
A method according to any of the preceding claims, wherein said paper sheet (10) has a paper weight comprised between 80 and 3000 grams per square meter.
A method according to any of the preceding claims, wherein said printing image pairs (100) corresponds to printing a set of images (101) from said image pairs (100) on one of said flaps (121;122) and to printing said set of corresponding images (102) from said image pairs (100) on the other flap (122;121) such that each of said image pairs (100) is divided by said respective fold line (13).
A method according to any of the preceding claims, wherein said providing planar electronics (20) on said opposite surface (12) of at least one of said flaps (120) corresponds to aligning said planar electronics (20) on said opposite surface (12) of at least one of said flaps (120) such that said planar electronics (20) coincide with said images (101;102) on said printing surface (11) of said respective flap (121;122).
A method according to any of the preceding claims, wherein each of said image pairs (100) comprises a front side image (103) of a laminated paper product (1) and a corresponding back side image (104) of a laminated paper product (1).
A method according to claim 6, wherein said folding each of said strips (110) along said respective fold line (13) corresponds to overlaying said front side images (103) and said corresponding back side images (104) onto each other, thereby forming pairs of images (100) overlaid onto each other.
A method according to claim 7, wherein said punching said laminated paper product (1) out of said overlaid flaps (130) corresponds to punching a pair of images (100) overlaid onto each other out of said overlaid flaps (130), thereby obtaining said laminated paper product (1).
A method according to any of the preceding claims, wherein said method further comprises the step of printing opacifying images (140) on said opposite surface (12) of said paper sheet (10) before die cutting said strips (110) from said paper sheet (10).
A method according to claim 9, wherein said method further comprises the step of aligning said opacifying images (140) with respect to said images (101;102) such that said opacifying images (140) coincide with said images (101;102) on said printing surface (11) of said respective flap (121;122).
A method according to any of the preceding claims, wherein said applying said adhesive (30) on said opposite surface (12) of at least one of said flaps (120) corresponds to applying hot melt glue on said opposite surface (12) of at least one of said flaps (120).
A method according to any of the preceding claims, wherein said applying said adhesive (30) on said opposite surface (12) of at least one of said flaps (120) corresponds to applying hot melt glue on said opposite surface of both flaps (120).
A system (2) for manufacturing a laminated paper product (1) with integrated electronics, wherein said system comprises:
- a paper sheet providing unit adapted to provide a paper sheet (10);

- a printing station adapted to print image pairs (100) on a printing surface (11) of said paper sheet (10);

- a die cutting unit (203) adapted to die cut strips (110) from said paper sheet (10), thereby obtaining strips (110) each comprising two flaps (120), a first flap (121) comprising a set of images (101) from said image pairs (100) and a second flap (122) comprising the corresponding set of images (102) from said image pairs (100);

- a planar electronics providing unit (204) adapted to provide planar electronics (20) on an opposite surface (12) to said printing surface (11) of at least one of said flaps (120);

- a gluing station (205) adapted to apply adhesive (30) on an opposite surface (12) to said printing surface (11) of at least one of said flaps (120);

- a folding station (206) adapted to fold each of said strips (110) along a respective fold line (13), thereby overlaying said flaps (120) onto each other and obtaining overlaid flaps (130);

- a pressure applying unit (207) adapted to apply pressure on said overlaid flaps (130); and

- a punching unit (208) adapted to punch said laminated paper product (1) out of said overlaid flaps (130).