One-step necked-bonded laminate process and apparatus
View Patent ↗A one-step method of making a necked-bonded laminate, wherein the layers of the laminate are formed and laminated within the same process. The method includes forming a nonwoven web, necking the nonwoven web, and immediately feeding the nonwoven web into a laminator where an elastomeric film is laminated to the nonwoven web. The elastomeric film may also be formed during the process prior to being fed into the laminator. Additionally, more than one nonwoven web may be formed and laminated to the elastomeric film during the process. The invention further includes apparatus for carrying out the one-step method.
1. A one-step, one-location method of making a necked-bonded laminate, comprising:
bonding a first plurality of filaments in a first bonding device operating at a first speed to form a first nonwoven web; necking the first nonwoven web; and feeding the first nonwoven web into a laminator operating at a second faster speed in a tensioned, necked condition, such that the first nonwoven web is conveyed from the first bonding device to the laminator within 24 seconds; and
laminating an elastomeric film to the necked first nonwoven web in the laminator;
wherein a difference between the first speed and the second speed necks the first nonwoven web before the first nonwoven web reaches 75% of a final crystallization and the neck-bonded laminate can be stretched by about 300% or more.
2. The method of claim 1 , wherein the first nonwoven web is conveyed from the first bonding device to the laminator within 18 seconds.
3. The method of claim 1 , wherein the first nonwoven web is conveyed from the first bonding device to the laminator within 12 seconds.
4. The method of claim 1 , further comprising conveying the first nonwoven web to a first heating device prior to feeding the first nonwoven web into the laminator.
5. The method of claim 4 , further comprising necking the first nonwoven web in the first heating device.
6. The method of claim 1 , further comprising stretching the elastomeric film and laminating the elastomeric film to the first nonwoven web while the elastomeric film is in a stretched position.
7. The method of claim 1 , further comprising creping the first nonwoven web after necking the first nonwoven web.
8. The method of claim 1 , wherein the first nonwoven web comprises a spunbond web.
9. The method of claim 1 , wherein the first nonwoven web comprises a meltblown web.
10. The method of claim 1 , further comprising:
bonding a second plurality of filaments in a second bonding device to form a second nonwoven web; necking the second nonwoven web; and feeding the second nonwoven web into the laminator, such that the second nonwoven web is conveyed from the second bonding device to the laminator within 24 seconds; and
laminating the elastomeric film between the first nonwoven web and the second nonwoven web within the laminator.
11. The method of claim 10 , wherein the second nonwoven web is conveyed from the second bonding device to the laminator within 18 seconds.
12. The method of claim 10 , wherein the second nonwoven web is conveyed from the second bonding device to the laminator within 12 seconds.
13. The method of claim 10 , further comprising conveying the second nonwoven web to a second heating device prior to feeding the second nonwoven web into the laminator.
14. The method of claim 13 , further comprising necking the second nonwoven web in the second heating device.
15. The method of claim 10 , wherein the second nonwoven web comprises a spunbond web.
16. The method of claim 10 , wherein the second nonwoven web comprises a meltblown web.
17. The method of claim 1 , further comprising slitting the first nonwoven web into two separate nonwoven web portions; necking both of the nonwoven web portions; feeding both nonwoven web portions into the laminator; and laminating the elastomeric film between the two nonwoven web portions within the laminator.
18. The method of claim 10 , wherein the first and second nonwoven webs have different widths prior to necking, and are necked different amounts than one another to end up with the same width as one another after necking.
19. The method of claim 1 , wherein the necking occurs before the first nonwoven web reaches a half-life of final crystallization.
20. A one-step, one-location method of making a necked-bonded laminate, comprising:
bonding a first plurality of filaments in a first bonding device operating at a first speed to form a first nonwoven web; necking the first nonwoven web; and feeding the first nonwoven web into a laminator operating at a second faster speed in a tensioned, necked condition, such that the first nonwoven web is conveyed from the first bonding device to the laminator within 24 seconds;
forming an elastomeric film, and feeding the elastomeric film into the laminator; and
laminating the elastomeric film to the necked first nonwoven web in the laminator;
wherein a difference between the first speed and the second speed necks the first nonwoven web before the first nonwoven web reaches 75% of a final crystallization and the necked-bonded laminate can be stretched by about 300% or more.
21. The method of claim 20 , wherein the first nonwoven web is conveyed from the first bonding device to the laminator within 18 seconds.
22. The method of claim 20 , wherein the first nonwoven web is conveyed from the first bonding device to the laminator within 12 seconds.
23. The method of claim 20 , further comprising conveying the first nonwoven web to a first heating device prior to feeding the first nonwoven web into the laminator.
24. The method of claim 23 , further comprising necking the first nonwoven web in the first heating device.
25. The method of claim 20 , further comprising stretching the elastomeric film and laminating the elastomeric film to the first nonwoven web while the elastomeric film is in a stretched position.
26. The method of claim 20 , further comprising creping the first nonwoven web after necking the first nonwoven web.
27. The method of claim 20 , wherein the first nonwoven web comprises a spunbond web.
28. The method of claim 20 , wherein the first nonwoven web comprises a meltblown web.
29. The method of claim 20 , further comprising:
bonding a second plurality of filaments in a second bonding device to form a second nonwoven web; necking the second nonwoven web; and feeding the second nonwoven web into the laminator, such that the second nonwoven web is conveyed from the second bonding device to the laminator within 24 seconds; and
laminating the elastomeric film between the first nonwoven web and the second nonwoven web within the laminator.
30. The method of claim 29 , wherein the second nonwoven web is conveyed from the second bonding device to the laminator within 18 seconds.
31. The method of claim 29 , wherein the second nonwoven web is conveyed from the second bonding device to the laminator within 12 seconds.
32. The method of claim 29 , further comprising conveying the second nonwoven web to a second heating device prior to feeding the second nonwoven web into the laminator.
33. The method of claim 32 , further comprising necking the second nonwoven web in the second heating device.
34. The method of claim 29 , wherein the second nonwoven web comprises a spunbond web.
35. The method of claim 29 , wherein the second nonwoven web comprises a meltblown web.
36. The method of claim 20 , further comprising slitting the first nonwoven web into two separate nonwoven web portions; necking both of the nonwoven web portions; feeding both nonwoven web portions into the laminator; and laminating the elastomeric film between the two nonwoven web portions within the laminator.
37. The method of claim 29 , wherein the first and second nonwoven webs have different widths prior to necking, and are necked different amounts than one another to end up with the same width as one another after necking.
38. The method of claim 20 , wherein the necking occurs before the first nonwoven web reaches a half-life of final crystallization.