Abstract
An RFID tag (1) comprises a substrate (2), an inlay (3), an antenna (4) and an integrated circuit on a chip (5) coupled to the antenna (4). The substrate (2) has a front surface (6), a back surface (7), a first side edge (8) and a second side edge (9). The inlay (3) comprises the antenna (4) and has a fold (10) that is configured to fold over one side edge (8, 9) of the substrate (2) from the front surface (6) to the back surface (7). At least the inlay (3) comprises at least one opening (12).
Claims
1. An RFID tag (1) that comprises a substrate (2), an inlay (3), an an-tenna (4) and an integrated circuit on a chip (5) coupled to the antenna (4), the substrate (2) has a front surface (6), a back surface (7), a first side edge (8) and a second side edge (9), the inlay (3) comprises the antenna (4) and has a fold (10) that is configured to fold over one side edge (8, 9) of the substrate (2) from the front surface (6) to the back surface (7), wherein at least the inlay (3) comprises at least one opening (12).
2. The RFID tag according to claim 1, wherein at least the inlay (3) comprises a row (11) of openings (12) at the fold (10), the row (11) being parallel to said side edge (8, 9).
3. The RFID tag according to claim 1, wherein the inlay (3) comprises one fold (10) that is configured to fold over the first side edge (8) and another fold (10) that is configured to fold over the second side edge (9) and the inlay (3) comprises a row (11) of openings (12) at both folds (10).
4. The RFID tag according to claim 1, wherein the RFID tag (1) comprises a face layer (13) on the inlay (3).
5. The RFID tag according to claim 4, wherein the inlay (3) and the face layer (13) comprises a fold (10) that is configured to fold over one side edge (8, 9) of the substrate (2) from the front surface (6) to the back surface (7), the face layer (13), the inlay (3) and the substrate (2) comprises a row (11) of openings (12) at the fold (10), the row (11) being parallel to the at least one side edge (8, 9).
6. The RFID tag according to claim 4, wherein the inlay (3) and the face layer (13) comprises one fold (10) that is configured to fold over the first side edge (8) and another fold (10) that is configured to fold over the second side edge (9) and the face layer (13), the inlay (3) and the substrate (2) comprises a row (11) of openings (12) at both folds (10).
7. The RFID tag according to claim 1, wherein the opening (12) is an elongated aperture.
8. The RFID tag according to claim 1, wherein the opening (12) is a circular hole.
9. The RFID tag according to claim 1, wherein the opening (12) is an array of sequential circular holes.
10. The RFID tag according to claim 1, wherein the opening (12) is a slit.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In the following the invention will be described in greater detail by means of preferred embodiments with reference to the attached drawings, in which
[0016] FIG. 1 shows a partial side view of a folded RFID tag of prior art;
[0017] FIG. 2 shows an inlay from above;
[0018] FIG. 3 shows a cross-sectional view of an RFID tag comprising the inlay of FIG. 2;
[0019] FIG. 4a shows the front side of the inlay of FIG. 2;
[0020] FIG. 4b shows the back side of the inlay of FIG. 2;
[0021] FIG. 5 shows an inlay from above;
[0022] FIG. 6 shows a cross-sectional view of an RFID tag comprising the inlay of FIG. 5;
[0023] FIG. 7a shows the front side of the inlay of FIG. 5;
[0024] FIG. 7b shows the back side of the inlay of FIG. 5;
[0025] FIG. 8 shows a front view of an RFID tag;
[0026] FIG. 9 shows a cross-sectional view of an RFID tag of FIG. 8;
[0027] FIG. 10 shows a front view of an RFID tag;
[0028] FIG. 11 shows a cross-sectional view of an RFID tag of FIG. 10;
[0029] FIG. 12a shows a front view of an inlay;
[0030] FIG. 12b shows a front view of an inlay;
[0031] FIG. 12c shows a front view of an inlay;
[0032] FIG. 13 shows a cross-sectional view of a curved surface with an RFID tag.
DETAILED DESCRIPTION OF THE INVENTION
[0033] FIG. 1 shows a partial side view of a folded RFID tag 100 of prior art. RFID tags are usually manufactured in a roll to roll process where a web comprising sequential RFID tags is reeled on a surface 200 of a curved roll core. The web of folded RFID tags 100 does not follow the surface 200 smoothly but forms bends 300 to some of the RFID tags 100. Wrinkles 400 may appear at the bends. The bend 300 causes detuning of the RFID tag 100, i.e. the read range of the RFID tag 100 is diminished. As the roll comprises multiple web layers there may be a remarkable number of detuned RFID tags 100.
[0034] FIG. 2 shows an inlay 3 from above. The inlay 3 comprises an antenna 4 and an integrated circuit on a chip 5 coupled to the antenna 4. The placing of the chip 5 may be different depending on the shape of the antenna 4. The inlay 4 comprises a row 11 of openings 12 that are cut through the inlay 4 and usually also through the antenna 4. The openings 12 are elongated apertures in FIG. 2 but their shape may vary. The opening 12 may be, for example, a circular hole, a row of circular holes or a slit as shown in FIGS. 12a, 12b and 12c. Dashed lines F show the area where the inlay is due to bend.
[0035] Regarding both FIGS. 2 and 5 the chip 5 should not be in the area demarcated by the dashed lines F. As the RFID tags 1 are usually manufactured in a roll-to-roll process it is shown in FIGS. 2 and 5 how the inlay 3 is situated in respect of the machine direction MD and cross direction CD on a web comprising sequential and/or parallel RFID tags 1.
[0036] FIG. 3 shows a cross-sectional view of an RFID tag 1. The RFID tag 1 comprises a face layer 13, an inlay 3 and a substrate 2. The face layer 13 may be a printable surface. The inlay 3 is as explained in connection with FIG. 2. The face layer 13, the inlay 3 and the substrate 2 are attached together by adhesive layers 14.
[0037] FIG. 4a shows the front side of the inlay 3 of FIG. 2 when it is bent. FIG. 4b shows the back side of the inlay 3 of FIG. 2 when it is bent. The area of the dashed lines F is now at the fold 10.
[0038] FIG. 5 shows another inlay 3 from above. The inlay 3 comprises an antenna 4 and an integrated circuit on a chip 5 coupled to the antenna 4. The placing of the chip 5 may be different depending on the shape of the antenna 4. The inlay 4 comprises two rows 11 of openings 12 that are cut through the inlay 4. The openings 12 are elongated apertures in FIG. 5 but their shape may vary. The opening 12 may be, for example, a circular hole, a row of circular holes or a slit as shown in FIGS. 12a, 12b and 12c. Dashed lines F show two areas where the inlay 3 is due to bend.
[0039] FIG. 6 shows a cross-sectional view of an RFID tag 1. The RFID tag 1 comprises a face layer 13, an inlay 3 and a substrate 2. The face layer 13 may be a printable layer. The inlay 3 is as explained in connection with FIG. 5. The face layer 13, the inlay 3 and the substrate 2 are attached together by adhesive layers 14.
[0040] FIG. 7a shows the front side of the inlay 3 of FIG. 5 when it is bent over the side edges of the substrate 2. FIG. 7b shows the back side of the inlay 3 of FIG. when it is bent over the side edges of the substrate 2. The areas of the dashed lines F are now at the fold 10 on the opposite sides of the inlay 3.
[0041] FIG. 8 shows a front view of an RFID tag 1. A face layer 13 is the outermost layer. The RFID tag 1 comprises openings 12 that penetrate through the RFID tag 1 from the first surface 6 to the second surface 7, i.e. the face layer 13 and the inlay 3 may become punched twice and the substrate 2 once. In the case of FIG. 8 the side edge 9 comprises the openings 12 but naturally it can also be the side edge 8 that has the openings 12.
[0042] FIG. 9 shows a cross-sectional view of an RFID tag 1. The RFID tag 1 comprises a face layer 13, an inlay 3 and a substrate 2. The face layer 13 may be a printable layer. The inlay 3 in the RFID tag 1 may be as explained in connection of FIG. 2 except that the openings 12 are formed after the structure of the RFID tag 1 is ready. The face layer 13, the inlay 3 and the substrate 2 are attached together by adhesive layers 14.
[0043] FIG. 10 shows a front view of another RFID tag 1. A face layer 13 is the outermost layer. The RFID tag 1 comprises openings 12 at both edges 8, 9 that penetrate through the RFID tag 1 from the first surface 6 to the second surface 7, i.e. the face layer 13 and the inlay 3 may become punched twice and the substrate 2 once.
[0044] FIG. 11 shows a cross-sectional view of an RFID tag 1. The RFID tag 1 comprises a face layer 13, an inlay 3 and a substrate 2. The face layer 13 may be a printable layer. The inlay 3 in the RFID tag 1 may be as explained in connection of FIG. 5 except that the openings 12 are formed after the structure of the RFID tag 1 is ready. The face layer 13, the inlay 3 and the substrate 2 are attached together by adhesive layers 14.
[0045] FIG. 12a shows a front view of an inlay 3 having a row 11 of openings 12. The openings 12 are circular holes.
[0046] FIG. 12b shows a front view of an inlay 3 having a row 11 of openings 12. The openings 12 are an array of sequential circular holes 12.
[0047] FIG. 12c shows a front view of an inlay 3 having a row 11 of openings 12. The openings 12 are slits that are made without removing material.
[0048] FIG. 13 shows a cross-sectional view of a curved surface 15 which an RFID tag 1 has been applied. Openings 12 at a fold 10 enhance the RFID tag 1 to conform to the curved surface 15 because the openings 12 give flexibility to the RFID tag 1. Thus, the openings 12 are significant also after the manufacturing process in the ready-made RFID tag 1.
[0049] It will be obvious to a person skilled in the art that, as the technology advances, the inventive concept can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.
