Process of making short fiber nonwoven molded articles

Patent metadata

Field	Value
Publication number	US-9546439-B2
Application number	US-201414277953-A
Country	US
Kind code	B2
Filing date	May 15, 2014
Priority date	May 15, 2014
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

A method of forming a nonwoven article comprising receiving fibrous material comprising thermoplastic fibers; processing the fibrous material to produce short fibers, wherein the processing step comprises granulation using at least one granulator with a screen; distributing the short fibers approximately evenly across an area to form a short fiber web, wherein the distributing step comprises a use of a recyclate spreader; heating the short fiber web to fuse the short fibers to form a nonwoven material; and forming a sheet of the nonwoven material.

First claim

What is claimed is:

1. A method of forming a nonwoven article, the method comprising:
a) receiving fibrous material comprising thermoplastic fibers, wherein at least a portion of the fibrous material is waste material;
b) processing the fibrous material to produce short fibers, wherein the processing step comprises granulation utilizing at least one granulator with a screen;
c) distributing the short fibers approximately evenly across an area to form a short fiber web, wherein the distributing step comprises using a recyclate spreader that reduces clumping of the short fibers by reducing the static charge of the short fibers;
d) heating the short fiber web to fuse the short fibers to form a nonwoven material;
e) forming a sheet of the nonwoven material; and
f) molding the sheet of the nonwoven material into a molded article having a three-dimensional shape
wherein the molded article is suitable for use as a sound absorption material.

2. The method of claim 1 , wherein the short fibers are blended before the distributing step to achieve a relatively consistent distribution of fibrous material.

3. The method of claim 1 , wherein the distributing step distributes the short fibers approximately evenly onto a facing material.

4. The method of claim 3 , wherein the facing material is formed of a non-woven preformed web, needle punched material, fabric, or combination thereof.

5. The method of claim 3 , wherein a second facing material is placed on top of the short fiber web after the distributing step.

6. The method of claim 1 , wherein the method includes a compacting step to achieve a desired density of the nonwoven material.

7. The method of claim 6 , wherein the compacting step comprises using at least one set of heated calendar rolls.

8. The method of claim 1 , wherein the nonwoven material exhibits selected air flow resistivity of about 275,000 Rayls/m to about 3,000,000 Rayls/m.

9. The method of claim 1 , wherein the molded article is surrounded by waste.

10. The method of claim 9 : wherein the molded article is separated from the waste.

11. The method of claim 10 , wherein the molded article is separated from the waste with a water jet, laser, die, or ultrasonic cutter.

12. The method of claim 10 , wherein the waste is recycled at the receiving step.

13. The method of claim 1 , wherein the processing step includes shredding with a single shaft shredder before the at least one granulator with the screen.

14. The method of claim 1 , wherein the processing step comprises granulation with two or more granulators arranged in series, with each granulator having at least one screen.

15. The method of claim 1 , wherein the short fibers after the processing step have an average length of about 2 mm to about 3 mm.

16. The method of claim 1 , wherein the heating step comprises a con oven to soften low-melt temperature short fibers and bond the short fibers together.

17. A method of forming a nonwoven article, the method comprising:
a) receiving fibrous material comprising thermoplastic fibers;
b) processing the fibrous material to produce short fibers, wherein the processing step comprises granulation using at least one granulator with a screen;
c) blending the short fibers achieve a relatively consistent distribution of fibrous material;
d) distributing the short fibers approximately evenly to form a short fiber web on a facing material, wherein the distributing step comprises use of a recyclate spreader;
e) heating the short fiber web and the facing material in an oven to form a nonwoven material;
f) compacting the nonwoven material,
g) forming a sheet of the nonwoven maternal;
h) shaping the sheet of nonwoven material into a molded article surrounded by waste;
i) separating the molded article from the waste; and
j) recycling the waste into the receiving step without performing melting or disambiguation steps prior to the receiving step,
wherein the nonwoven material is suitable for use as a sound absorption material, and
wherein the nonwoven, material exhibits a selected air flow resistivity of about 275,000 Rayls/m to about 3,000,000 Rayls/m.

18. The method of claim 17 , wherein a second facing material is placed on top of the short fiber web after the distributing step.

19. The method of claim 17 , wherein the compacting step comprises using at least one set of heated calendar rolls.

20. The method of claim 1 , wherein the waste material does not undergo melting or disambiguation steps prior to the receiving step.

Assignees

• Zephyros Inc

Inventors

• Coates Michael William
• Gibbons Philip John
• Cain John

Classifications

• B29C69/001

  a shaping technique combined with cutting, e.g. in parts or slices combined with rearranging and joining the cut parts (for reinforced material B29C70/545; B29C49/4278, B29C51/268 take precedence) · CPC title

• D04H1/5405

  at spaced points or locations · CPC title

• B32B5/022

  Non-woven fabric · CPC title

• D04H1/4274 Primary

  Rags; Fabric scraps · CPC title

• D04H1/732

  by fluid current, e.g. air-lay · CPC title