Hydroentangled polyolefin web

• US 5,023,130 A
• Filed: 08/14/1990
• Issued: 06/11/1991
• Est. Priority Date: 08/14/1990
• Status: Expired due to Term

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Smith, Larry M., Simpson, Penny C.
• Primary Examiner(s): Bell, James J.
• Application Number:
  US07/567,207
• Time in Patent Office: 301 Days
• Field of Search: 28/104, 428/299, 428/903, 428/224, 428/227
• US Class Current: 442/408
• CPC Class Codes: D04H 1/49 entanglement by fluid jet in combination with another consolidation means
• CPC Class Codes: Y10S 428/903 Microfiber, less than 100 micron diameter
• CPC Class Codes: Y10T 442/689 Hydroentangled nonwoven fabric

Abstract

A process is disclosed for hydroentangling continuous polyolefin filament fibers to form a fabric web. The fibers are supported on a 60 to 150 mesh screen and passed under high pressure water jets operating at at least 2000 psi and providing a total impact energy of at least 0.7 MJ-N/Kg to entangle the fibers. Preferably, the hydroentangled web is thereafter passed under finer finishing water jets operating at a pressure of between 300 to 1200 psi to redistribute the fibers. If desired, a finish may be applied to the entangled web. The resulting hydroentangled web has considerably increased visual uniformity, opacity, softness, comfort, strength and barrier properties compared to prior art webs thereby making it particularly useful as a disposable industrial garment.

Claims

1. A process for hydroentangling an unbonded, nonwoven polyolefin web comprising the steps of:

(a) supporting a lightweight web of continuous polyolefin filament fibers on a fine mesh screen; and

(b) passing the supported web underneath high energy water jets operating at a pressure of at least 2000 psi and providing a total impact energy of at least 0.7 MJ-N/Kg to entangle the web in a random manner.

2. A process according to claim 1 further comprising passing the hydroentangled web of step (b) underneath finishing water jets operating at 300 to 1200 psi to redistribute the randomly entangled fibers.

3. A process according to claim 1 wherein the high energy jets operate at a pressure of at least 2100 psi.

4. A process according to claim 1 wherein the high energy jets provide a total impact energy of between 0.8 and 1.6 MJ-N/Kg to the web.

5. A process according to claim 1 further comprising the step of applying a finish to the hydroentangled web.

6. A process according to claim 5 wherein the finish is selected from the group consisting of hydrophilic finishes, hydrophobic finishes, disperse dyes, surface stabilizers, wetting agents and acrylic binders.

7. A process according to claim 1 wherein the web is supported on a 75 or 100 mesh screen.

8. A process according to claim 1 wherein the polyolefin web is comprised of plexifilaments.

9. A process according to claim 1 wherein the polyolefin comprises polyethylene.

10. An unbonded, nonwoven polyolefin web produced by the process of any of claims 1-9.

11. An unbonded, nonwoven hydroentangled polyolefin web having a strip tensile strength of at least 3.5 lbs/oz/yd², an opacity of at least 90%, and an average pore size of less than 10 microns.

12. A hydroentangled web according to claim 11 further having a comfort rating of at least 5.0.

13. A hydroentangled web according to claim 11 wherein the polyolefin comprises polyethylene.