Method for producing a finishing layer containing a window for a portable data storage medium and said finishing layer

1. A method for producing a finishing layer containing a window for a portable data storage medium, comprising the steps:

providing a transparent plastic-based support layer for covering a core layer comprising a window,

applying to the support layer an opaque color layer by screen printing, wherein the color layer comprises a cutout having the dimensions of the window,

applying to the opaque color layer a first transparent buffer layer by screen printing,

applying a design color layer over the buffer layer by offset printing, and

coating a transparent finish over the design color layer.

2. The method according to claim 1 , including applying a second transparent mediatory layer over the design color layer by offset printing prior to applying the transparent finish.

3. The method according to claim 1 , wherein the cutout precisely matches or is slightly smaller than a display area of an active display element.

4. The method according to claim 1 , including applying a second color layer to the support layer in the same manner as the first layer, the second layer comprising a cutout matching the cutout of the first color layer.

5. The method according to claim 1 , including using a water-based color for the color layer.

6. The method according to claim 1 , including applying the color layers in a liquid state so that the color layers have a thickness of 10 to 30 μm in a dry state.

7. The method according to claim 1 , including using a PET film as the support layer.

8. The method according to claim 4 , including applying the second color layer to the bottom side of the support layer.

9. The method according to claim 1 , including applying the design color layer to the support layer prior to applying the first buffer layer.

10. A use of the method recited in claim 1 for producing a portable data storage medium having a window in the top finishing layer, wherein the finishing layer recited in claim 1 is produced and said layer is bonded to a core layer comprising an active display element, with the result that the window comes to be located above the display area of the active display element.

11. A portable data storage medium comprising an active display element disposed in a core layer, and which display element is visible from a viewing side through a surface of the portable data storage medium, wherein a finishing layer is disposed over the core layer having the display element in a window of the core layer, the outer surface of said finishing layer facing away, and forming the surface of the portable data storage medium, and wherein the finishing layer comprises:

a transparent support layer having a thickness between 50 and 100 μm covering the core layer,

an opaque color layer applied to the transparent support layer, said opaque layer having a portion cut out above the display area of the active display element and having a height between 10 and 80% of the height of the support layer in a dry state,

a primer layer applied to the opaque color layer, said primer layer having a height which is between 10% and 40% of the height of the support layer in the dry state,

a design color layer over the primer layer,

and a finish layer coated over the design color layer, said finish layer having a top surface forming a surface of the portable data storage medium.

12. The data storage medium according to claim 11 , wherein the color layer is made of at least two identical color layers.