Method for making a fibrous article
View Patent ↗The present invention generally relates to a method and apparatus for a making a formed fibrous article and more specifically to method and apparatus for making a formed fibrous article useful as an absorbent core structure in a disposable sanitary article such as a sanitary napkin, panty liner, diaper or the like. The present invention also relates to a disposable sanitary article including a formed fibrous article according to the present invention as a core structure thereof.
1. A method of making a formed fibrous article comprising the steps of:
forming a formed fibrous article having a three dimensional profile;
pin-calendering the fibrous article in a pin calendering station between a first roll and a second roll, wherein the fibrous article is conveyed through a nip defined between the first roll and the second roll without the use of a carrier layer.
2. The method according to claim 1 , wherein the step of forming a formed fibrous article having a three dimensional profile comprises the steps of:
forming a formed fibrous article: and
passing the formed fibrous article through a calendering station to thereby provide the formed fibrous article with the three dimensional profile.
3. The method according to claim 2 , wherein the calendering station includes a vacuum roll and an opposed calender roll.
4. The method according to claim 3 , wherein a surface of the calender roll includes at least one recess, the recess being structured and arranged to provide the formed fibrous article with the three dimensional profile.
5. The method according to claim 4 , wherein the formed fibrous article having a three dimensional profile includes a planar portion and at least one raised portion extending upwardly relative to the planar portion.
6. The method according to claim 5 , wherein the planar portion and the raised portion have each has a different thickness and a different density but have a constant basis weight.
7. The method according to claim 6 , wherein the step of forming the fibrous article comprises the steps of:
providing fibrous pulp, maintaining the fibrous pulp in a chamber, mounting a mold to a rotating forming drum, rotating the mold on the rotating forming drum until the mold is arranged in communication with the chamber, and drawing the fibrous pulp into the mold to thereby form the fibrous article.
8. The method according to claim 7 , wherein the first roll comprises a vacuum roll and the second roll comprises a pin calender roll.
9. The method according to claim 8 , wherein a surface of the vacuum roll includes a plurality of holes and the pin calender roll includes a plurality of pins extending outwardly from a surface of the roll.
10. The method according to claim 9 , wherein each one of the plurality of pins is arranged such that it does not overlap with any of the plurality of holes.
11. The method according to claim 10 , wherein the pin calender roll includes a first area having a plurality the pins extending outwardly from the surface of the roll, a first recess, a second recess, a land area arranged between the first and second recess, the land area including a plurality of the pins extending outwardly from the surface of the roll.
12. The method according to claim 11 , wherein the first recess, second recess and land area are structured and arranged to correspond in location to the raised portion of the formed fibrous article when the formed fibrous article passes through the pin calendering station.
13. The method according to claim 12 , wherein the fibrous article is formed in the mold and transferred to the calendering station without the use of a carrier layer.
14. The method according to claim 13 , further comprising:
transferring the fibrous article from the vacuum roll of the calendering station to the vacuum roll of the pin calendering station.
15. The method according to claim 14 , wherein the fibrous article is transferred from the vacuum roll of the calendering station to the vacuum roll of the pin calendering station without the use of a carrier layer.
16. The method according to claim 15 , further comprising transferring the fibrous article from the vacuum roll of the pin calendering station to a transfer wheel.
17. The method according to claim 16 , wherein the transfer wheel includes a vacuum roll and a porous conveyor belt that extends around the vacuum roll.