Air-laid blank for sound absorbing or damping, and methods and appartuses for producing such
AssigneeStora Enso OYJ
InventorMaria Törnblom
Life of this patent
Estimating the term…
Abstract
An air-laid blank (10) comprises natural fibers and a polymer binder. The air-laid blank (10) comprises multiple portions (11) having a local fiber orientation distribution that is different from a fiber orientation distribution of a remaining portion (13) of the air-laid blank (10). The air-laid blank (10) can be used to produce sound absorbing or damping articles (20). The invention also relates to methods and apparatuses (100) for producing such air-laid blanks (10).
Claims23
An air-laid blank comprising:
- natural fibers;
- and
- a polymer binder,
- wherein the air-laid blank further comprises multiple portions having a local fiber orientation distribution that is different from a fiber orientation distribution of a remaining portion of the air-laid blank.
A method of producing an air-laid blank, the method comprising:
- introducing natural fibers and a thermoplastic polymer binder, or a mixture of the natural fibers and the thermoplastic polymer binder, or both into at least one inlet of a forming head;
- transporting the natural fibers and the thermoplastic polymer binder, or the mixture, or both to an outlet of the forming head;
- capturing the natural fibers and the thermoplastic polymer binder, or the mixture, or both as an unbound air-laid web on a collector arranged in connection with the outlet of the forming head;
- applying gas pulses onto multiple portions of the unbound air-laid web to induce local distortions of fiber orientations in the multiple portions;
- and
- heat treating the unbound air-laid web to at least partly melt the thermoplastic polymer binder and form an air-laid blank.
A method of producing an air-laid blank, the method comprising:
- introducing natural fibers into at least one inlet of a forming head;
- transporting the natural fibers to an outlet of the forming head;
- capturing the natural fibers as a web of natural fibers on a collector arranged in connection with the outlet of the forming head;
- applying gas pulses onto multiple portions of the web of natural fibers on the collector to induce local distortions of fiber orientations in the multiple portions;
- applying a polymer binder onto the natural fibers;
- and
- heat treating the web of natural fibers and the polymer binder to form an air-laid blank.
-28. (canceled)
Dependencies are inferred from the claim text.