Inlet sheet for a book-like electronic identification document

1. An inlay sheet configured to be used in a book-like identification document, the inlay sheet comprising:

a first hinge layer comprising polycarbonate;

a second hinge layer comprising a flexible material different to polycarbonate, the second hinge layer being attached to the first hinge layer;

a first datapage layer; and

a second datapage layer;

wherein the first datapage layer and the second datapage layer are attached to the first hinge layer and the second hinge layer, respectively, such that the first and second hinge layers are positioned between the first and second datapage layers forming a datapage section having a datapage thickness (tdp), the first and second datapage layers forming a datapage inner front edge;

wherein the first and second hinge layers extend beyond the datapage inner front edge such that a hinge section is formed having a hinge thickness (th) smaller than the datapage thickness (tdp); and

wherein the first hinge layer includes a surface pattern comprising a plurality of at least one of voids or cavities, and the plurality of at least one of voids or cavities are filled with material of the second hinge layer.

2. The inlay sheet of claim 1 , further comprising:

a third hinge layer comprising polycarbonate, the second hinge layer being positioned between and attached to the first and third hinge layers.

3. The inlay sheet of claim 2 , wherein the first, second, and third hinge layers form a common front edge closed by at least one of a polycarbonate strip or a strip formed during lamination of the hinge layers made of polycarbonate by at least one of pressing or squeezing.

4. The inlay sheet of claim 2 , wherein the third hinge layer includes another surface pattern.

5. The inlay sheet of claim 4 , wherein the another surface pattern comprises a plurality of at least one of voids or cavities.

6. The inlay sheet of claim 5 , wherein the plurality of at least one of voids or cavities of the another surface pattern are filled with material of the second hinge layer.

7. The inlay sheet of claim 2 , wherein at least one of:

the hinge thickness (th) is at least 30% smaller than the datapage thickness (tdp); or

a hinge layer thickness (thl) of at least one of the first or third hinge layers is at least 80% smaller than a datapage layer thickness (tpl) of at least one of the first or second datapage layers.

8. The inlay sheet of claim 2 , herein at least one of:

the datapage thickness (tdp) is smaller than 600 μm;

the hinge thickness (th) is smaller than 300 μm;

respective datapage thicknesses (tdp 1 , tdp 2 ) of the first and second datapage ers are smaller than 300 μm; or

respective hinge layer thicknesses (thl) of the first and third hinge layers are smaller t 100 μm.

9. The inlay sheet of claim 1 , wherein the surface pattern extends at least partly in the hinge section.

10. The inlay sheet of claim 1 , wherein at least a component of an RFID element is positioned in the second hinge layer.

11. The inlay sheet of claim 10 , wherein the component extends at least in part in the datapage section.

12. The inlay sheet of claim 1 , wherein at least one printed or laser engraved pattern is provided in the hinge section.

13. The inlay sheet of claim 1 , wherein a hinge layer thickness (thl 2 ) of the first hinge layer is at least 80% smaller than a hinge layer thickness (thl 1 ) of the second hinge layer.

14. A method for manufacturing an inlay sheet, the method comprising:

providing a first hinge layer comprising polycarbonate;

providing a second hinge layer comprising a flexible material different to polycarbonate;

generating a defined pattern comprising a plurality of at least one of voids or cavities in the first hinge laver;

filling the plurality of at least one of voids or cavities with material of the second hinge layer during bonding of the first and second hinge layers;

providing a first datapage layer forming a part of a datapage section;

providing a second datapage layer forming another part of the datapage section; and

bonding together the first and second hinge layers and the first and second datapage layers such that the first and second hinge layers are positioned between the first and second datapage layers and the first and second hinge layers extend beyond a datapage inner front edge, forming a hinge section having a hinge section thickness (th) smaller than a datapage section thickness (tdp).

15. The method of claim 14 , further comprising:

providing a third hinge layer comprising polycarbonate;

positioning the second hinge layer between the first and third hinge layers; and

bonding the first, second and third hinge layers to each other.

16. The method of claim 15 , further comprising

generating another defined pattern comprising a plurality of at least one of voids or cavities in the third hinge layer; and

filling the plurality of at least one of voids or cavities of the another defined pattern with material of the second hinge layer during bonding of the first, second and third hinge layers.