Method and apparatus for forming a package comprising a stack of absorbent tissue paper material and a packaging

1. Method for forming a package comprising a stack of absorbent tissue paper material and a packaging,

the tissue paper material in said stack forming panels having a length, and a width perpendicular to said length, said panels being piled on top of each other to form a height extending between a first end surface and a second end surface of the stack, and

the packaging encircling the stack so as to maintain the stack in a compressed condition in said package without a clearance space between the packaging and a top and bottom of the stack, with a selected packing density D0 of said stack, and a selected packing height H0; wherein

said absorbent tissue paper material is a dry crepe material, and said selected packing density D0 is between 0.30 and 0.95 kg/dm 3 , or alternatively,

said absorbent tissue paper material is a structured tissue material, and said selected packing density D0 is between 0.20 and 0.75 kg/dm 3 , or alternatively

said absorbent tissue paper material is a combination material, comprising at least a dry crepe material and at least a structured tissue material, and the selected packing density D0 is between 0.25 and 0.80 kg/dm 3 ;

the method comprising:

forming said stack of absorbent tissue paper material;

compressing each portion of said stack in a direction along said height to assume a temporary height H1 being c1×H0, where c1 is between 0.30 and 0.95; and

applying said packaging to the stack,

wherein a springback force exerted by the stack towards the packaging is less than a springback force exerted by a similar stack that is compressed directly to the packing height H0 without a preceding step of temporary compression to the temporary height H1.

2. Method according to claim 1 , wherein c1 is between 0.30 and 0.90.

3. Method according to claim 1 , wherein the absorbent tissue paper material is a dry crepe material, and the selected packing density D0 is between 0.30 and 0.65 kg/dm3.

4. Method according to claim 1 , wherein the absorbent tissue paper material is a structured tissue material, and the selected packing density D0 is between 0.20 and 0.50 kg/dm3.

5. Method according to claim 1 , wherein the absorbent tissue paper material is a combination material, comprising at least a dry crepe material and at least a structured tissue material, and the selected packing density D0 is between 0.25 and 0.55 kg/dm3.

6. Method according to claim 4 , wherein the structured tissue paper material is a TAD (Through-Air-Dried) material, an UCTAD (Uncreped-Through-Air-Dried) material, an ATMOS (Advanced-Tissue-Molding-System) material, or a NTT material.

7. Method according to claim 5 , wherein the absorbent tissue paper material is a combination material comprising at least one ply of a structured tissue material and one ply of a dry crepe material.

8. Method according to claim 1 wherein said step of compressing each portion of said stack in a direction along said height to assume a temporary height H1 is performed by simultaneous compression of all portions of said stack to said temporary height H1.

9. Method according to claim 1 , wherein said step of compressing each portion of said stack in a direction along said height to assume a temporary height H1 is performed by consecutive compression of each portion of said stack to said temporary height.

10. Method according to claim 9 , wherein said consecutive compression is performed by feeding of said stack through an inclined passage or a nip.

11. Method according to claim 1 , wherein said step of compressing each portion of said stack in a direction along said height to assume a temporary height H1 is performed while the stack is stationary.

12. Method according to claim 1 , wherein said step of compressing each portion of said stack in a direction along said height to assume a temporary height H1 is performed while the stack is moving.

13. Method according to claim 1 wherein said step of compressing each portion of said stack in a direction along said height to assume a temporary height H1 is adapted to maintain said height H 1 for a time period greater than 0 but less than 10 min.

14. Method according to claim 1 , wherein said step of forming said stack comprises:

forming a log of absorbent tissue paper material, the log comprising tissue paper material for at least two, corresponding stacks, and

cutting said log to form said stack.

15. Method according to claim 1 , wherein said stack is a stack of folded absorbent tissue paper material.

16. Method according to claim 15 , wherein said folded absorbent tissue paper material is in the form of a continuous web.

17. Method according to claim 16 , wherein the continuous web is Z-folded.

18. Package comprising a stack and a packaging as provided by the method in accordance with claim 1 .

19. Method according to claim 1 , wherein the absorbent tissue paper material is a dry crepe material, and the selected packing density D0 is between 0.35 and 0.65 kg/dm3.

20. Method according to claim 1 , wherein the absorbent tissue paper material is a structured tissue material, and the selected packing density D0 is between 0.23 and 0.50 kg/dm3.

21. Method according to claim 1 , wherein the absorbent tissue paper material is a combination material, comprising at least a dry crepe material and at least a structured tissue material, and the selected packing density D0 is between 0.30 and 0.55 kg/dm3.

22. Method according to claim 1 , wherein the stack is compressed by decreasing a distance between parallel surfaces, between which the stack is disposed, in a direction perpendicular to the parallel surfaces.