Absorbent structure for sanitary articles and method for its production

1 . An absorbent structure, comprising:

an absorbent pad comprising cellulose fluff and having at least one through-opening elongated along a longitudinal axis, wherein said at least one through-opening has a central section and two end sections located on opposite sides of the central section, and wherein the central section has a width greater than a width of each of the end sections,

at least one fluff-free absorbent insert comprising a non-woven layer in which superabsorbent material is incorporated,

wherein the fluff-free absorbent insert has a shape elongated along said longitudinal axis and has a central section and two end sections located on opposite sides of the central section of the at least one fluff-free absorbent insert,

wherein the central section and the two end sections of the at least one fluff-free absorbent insert are housed, respectively, in the central section and in respective end sections of the at least one through-opening, and

wherein between the at least one fluff-free absorbent insert and longitudinal edges of the central section of the at least one through-opening, two longitudinal channels are formed located on opposite sides of the at least one fluff-free absorbent insert.

2 . The absorbent structure of claim 1 , wherein said central section of the at least one through-opening has longitudinal edges that are straight and parallel to the longitudinal axis.

3 . The absorbent structure of claim 1 , wherein the at least one fluff-free absorbent insert has a width substantially equal to a width of each of said end sections of the at least one fluff-free absorbent insert.

4 . The absorbent structure of claim 1 , wherein the at least one fluff-free absorbent insert has a constant width along the longitudinal axis.

5 . The absorbent structure of claim 1 , wherein said central section of said through-opening and/or said central section of said fluff-free absorbent insert have longitudinal edges with a curved shape so that each of said two longitudinal channels has at least one curved longitudinal edge.

6 . The absorbent structure of claim 1 , comprising two non-woven webs, which sandwich the absorbent pad and said at least one fluff-free absorbent insert.

7 . The absorbent structure of claim 6 , wherein said two non-woven webs are fixed together through said two longitudinal channels.

8 . A method for producing absorbent structures, comprising:

forming an array of absorbent pads comprising cellulose fluff, wherein each of said absorbent pads of the array of absorbent pads has at least one through-opening elongated along a longitudinal axis, wherein said at least one through-opening has a central section and two end sections located on opposite sides of the central section, and wherein the central section has a width greater than a width of each of the end sections,

forming an array of fluff-free absorbent inserts comprising at least one non-woven layer in which superabsorbent material is incorporated, wherein said fluff-free absorbent inserts of the array of fluff-free absorbent inserts have a shape elongated along said longitudinal axis and have a central section and two end sections, and

placing said fluff-free absorbent inserts within respective through-openings of said absorbent pads so that the central sections and the end sections of the fluff-free absorbent inserts are housed, respectively, in the central sections and in respective end sections of respective through-openings,

wherein between said fluff-free absorbent inserts and longitudinal edges of respective central sections of the through-openings, longitudinal channels are formed located on opposite sides of the fluff-free absorbent inserts.

9 . The method of claim 8 , comprising fixing together first and second continuous non-woven webs through said longitudinal channels.

10 . The method of claim 8 , wherein said central sections of said through-openings and/or said central sections of said fluff-free absorbent inserts have longitudinal edges with a curved shape so that each of said longitudinal channels has at least one curved longitudinal edge.