INFORMATION CARRIER WITH IMPROVED DETECTION ACCURACY BY A MULTILAYER BUILD UP OF THE INFORMATION CARRIER

Abstract

The invention relates to an information carrier with an enhanced capacitive contrast between the desired electrically conductive elements, i.e. the touch points, and the necessary, but interfering electrically conductive elements, i.e. the coupling area and the conductive traces. The invention also relates to a method for the manufacture of said information carrier and a use of said information carrier.

Claims

1. A capacitive, planar information carrier (1), comprising an electrically non-conductive substrate (2) made from an absorbing material, and partially applied, electrically non-conductive mask layer (8) and at least a partially applied electrically conductive layer (7), wherein, a) the electrically non-conductive mask layer (8) covers the electrically non-conductive substrate (2) only partially, creating gaps (6) where the substrate (2) is not covered by the electrically non-conductive mask layer (8) and b) the at least one electrically conductive layer (7) is applied on the mask layer (8) so that the material of the electrically conductive layer (7) fills the gaps (6) and covers partially the electrically non-conductive mask layer (8).

2. The information carrier according to claim 1, wherein an additional graphic overprint is printed on top of the uppermost electrically conductive layer of the information carrier.

3. The information carrier according to claim 1, wherein the material of the electrically conductive layer (7) penetrates into the upper most layers of the absorbing substrate (2) in the gaps (6).

4. The information carrier (1) according to claim 1, wherein the gaps (6) have an essentially circular area and the elements obtained by filling the gaps with the material of the electrically conductive layer (7) form touch points (3).

5. The information carrier (1) according to claim 1, wherein the material of the electrically conductive layer (7) which is present on the electrically non-conductive mask layer (8) forms conductive traces (4) and a coupling area (5).

6. The information carrier according to claim 1, wherein the electrically non-conductive substrate is made of absorbing paper or an absorbing cartoon material.

7. The information carrier (1) according to claim 1, wherein the thickness of the substrate (2) is between 20 to 1000 μm, preferably 50 to 500 μm, most preferably between 100 to 300 μm.

8. The information carrier (1) according to claim 1, wherein the electrically non-conductive substrate (2) consists of a flat, non-conductive material, in particular paper, cardboard, wood-based material, composite, textile, leather or a combination thereof.

9. The information carrier (1) according to claim 1, wherein the electrically non-conductive substrate (2) is flexible.

10. The information carrier (1) according claim 1, wherein the electrically non-conductive mask layer (8) consists of electrically non-conductive ink.

11. The information carrier (1) according to claim 1, wherein the electrically non-conductive mask layer (8) and the at least one electrically conductive layer (7) are manufactured with additive printing methods selected from a group comprising flexo printing, screen printing, gravur printing, offset printing and/or digital printing.

12. The information carrier (1) according to claim 1, wherein the at least one electrically conductive layer (7) consists of materials selected from a group comprising metal layer, layer containing metal particles or nanoparticles, containing electrically conductive particles, in particular carbon black, graphite, graphene, ATO, electrically conductive polymer layer, in particular Pedot, PANI, polyacetylene, polypyrrole, polythiophene and/or pentacene or any combination of these.

13. A method for the manufacture of an information carrier (1) according to claim 1, comprising a front side (9) and the back side (10) comprising the following steps: a) providing an electrically non-conductive substrate (2), b) partial application of an electrically non-conductive mask layer (8) on the front side (9) of the electrically non-conductive substrate (2), wherein gaps (6) are created by the partial application of the mask layer (8) where the electrically non-conductive substrate (2) is not covered by the electrically non-conductive mask layer (8), c) application of the at least one electrically conductive layer (7) on the front side (9) of the information carrier (1), wherein the electrically conductive material of the electrically conductive layer (7) fills the gaps (6) and covers at least partially the electrically non-conductive mask layer (8).

14. The method according to claim 13, wherein an additional graphic overprint is printed on top of the uppermost electrically conductive layer of the information carrier.

15. A method for reading out an information carrier (1) according to claim 1 by a touch screen (12), wherein the back side (10) of the information carrier (1) is brought in contact with a touch screen (12).

16. A use of an information carrier (1) according to claim 1, wherein the electrically conductive material in the gaps (6) generates a local change of capacitance on a touch screen (12).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0064] These and other objects, features and advantages of the present invention will best be appreciated when considered in view of the following description of the accompanying drawings:

[0065] FIG. 1 shows a side view of an information carrier where steps a and b of the method of manufacture have been carried out, i.e. the electrically non-conductive substrate has been provided and the electrically non-conductive mask layer has been applied to the front side of the substrate.

[0066] FIG. 2 shows a side view of an information carrier where the method of manufacture has been completed, i.e. the at least one electrically conductive layer has been applied.

[0067] FIG. 3 shows a side view of an information carrier according to the present invention when brought in contact with a touch screen for reading out the information carrier.

[0068] FIG. 1 shows a side view of an information carrier (1) according to the present invention where steps a and b of the method of manufacture have been carried out. This means that the electrically non-conductive substrate (2) has been provided and the electrically non-conductive mask layer (8) has been applied to the front side (9) of the substrate (2). FIG. 1 shows that the mask layer (8) is partially applied on the front side (9) of the substrate (2) of the information carrier (1). The areas of the substrate (2) where no mask layer (8) is applied are referred to as gaps (6) in the sense of this invention.

[0069] FIG. 2 shows a side view of an information carrier (1) according to the present invention where all three steps of the method for manufacture have been carried out. The gaps (6) between the partially applied mask layer (8) are filled with electrically conductive ink. As an absorbing substrate is used as a substrate (2) the electrically conductive ink penetrates into the substrate material (2). By this, the effective distance between the back side (10) of the information carrier (1) and the touch point (3) is reduced. According to formula A which can be found in the description of the present invention, a reduced distance leads to an enhanced capacitance C of the electrically conductive element in question. The touch points (3) of the present invention represent the desired elements of the information carrier (1) according to the present invention, as the detection of these touch points (3) is the purpose of the invention. The at least one electrically conductive layer (7) forms the coupling area (4) and the conductive traces (5). They represent the necessary, but interfering elements of the information carrier (1). Their distance to the back side (10) of the information carrier (1) is increased as they are printed on top of the electrically non-conductive mask layer (8). Thus, they have a reduced capacitance compared to the touch points (3).

[0070] The difference in capacitance between the touch points (3) on the one hand and the coupling area (4) and the conductive traces (5) on the other hand is referred to as capacitive contrast in the sense of this invention. The capacitive contrast between the desired and the necessary, but interfering elements is increased according to the present invention by making use of different effective distances of these electrically conductive elements. This is realized by the sophisticated built-up of the information carrier (1) according to the present invention.

[0071] FIG. 3 shows a sight view of an information carrier (1) according to the present invention when brought in contact with a touch screen for reading out the information carrier (1). It can be seen that the information carrier (1) faces the touch screen (12) with the back side (10) by using the information carrier (1) according to the present invention in the manner described, it is made use of the different effective distances of the touch points (3) on the one hand and the coupling area (4) and conductive traces (5) on the other hand.

LIST OF REFERENCE SIGNS

[0072] 1 Capacitive information carrier [0073] 2 Electrically non-conductive substrate [0074] 3 Electrically conductive layer (touch points) [0075] 4 Electrically conductive layer (conductive traces) [0076] 5 Electrically conductive layer (coupling area) [0077] 6 Gap [0078] 7 Electrically conductive layer [0079] 8 blocking layer (varnish mask) [0080] 9 Front side [0081] 10 Back side [0082] 11 device with touch screen [0083] 12 touch screen