Method of making strand-reinforced elastomeric composites
View Patent ↗A method of making mutually-reinforced elastic strand/film composites and laminates in which film breakage, strand breakage, and strand alignment problems are minimized or avoided. The method includes casting an elastomeric adhesive film onto a chill roll, extruding elastic strands onto the film while the film is on a chill roll, and stretching the film and strand composite. The stretched composite may be laminated between two facing sheets. Additionally, tension in the composite may be controlled through film composition, strand composition, add-on rate, stretching the composite, and combinations of any of these approaches.
1. A method of making an elastomeric composite, comprising:
casting a continuous non-foamed elastomeric adhesive film directly onto a first chill roll;
separately extruding a plurality of continuous elastic strands directly onto the non-foamed film to create a continuous strand-reinforced composite; and
stretching the continuous composite as a single unit.
2. The method of claim 1 , further comprising passing the film onto a second chill roll and extruding the plurality of elastic strands onto the film while the film is in contact with the second chill roll.
3. The method of claim 1 , comprising stretching the composite by at least 200%.
4. The method of claim 1 , wherein the plurality of elastic strands comprises at least one of a group consisting of raw polymers, a mixture of polymers, and tackified polymers.
5. The method of claim 1 , wherein the plurality of elastic strands comprises at least one of a group consisting of elastomeric polymer compositions, tackified polymers, olefinic copolymers, ethylene-propylene-diene monomer, styrene-isoprene-styrene, styrene-butadiene-styrene, styrene-ethylene/butylene-styrene, styrene-ethylene/propylene-styrene, polyurethane, polyisoprene, cross-linked polybutadiene, and combinations thereof.
6. The method of claim 1 , wherein the plurality of elastic strands comprises a tackifier including at least one type of hydrocarbon selected from a group consisting of petroleum distillates, rosin, rosin esters, polyterpenes derived from wood, polyterpenes derived from synthetic chemicals, and combinations thereof.
7. The method of claim 1 , wherein the elastomeric adhesive film comprises an elastomeric, hot melt, pressure-sensitive adhesive.
8. The method of claim 1 , wherein the plurality of elastic strands comprises between about 5% and about 50% by weight of the composite.
9. The method of claim 1 , wherein the plurality of elastic strands comprises between about 10% and about 35% by weight of the composite.
10. The method of claim 1 , further comprising laminating the stretched composite between a first facing sheet and a second facing sheet.
11. The method of claim 10 , wherein the first and second facing sheets are each selected from a group consisting of a nonwoven web and a film.
12. The method of claim 11 , wherein the nonwoven web is selected from a spunbond web and a meltblown web.
13. The method of claim 1 , wherein the plurality of elastic strands is extruded onto the elastomeric adhesive film at an add-on rate of between about 5 and about 50 grams per square meter before stretching.
14. The method of claim 13 , further comprising controlling tension in the elastomeric composite through at least one of: selection of film composition, selection of strand composition, add-on rate, stretching the composite, selection of substrate, and combinations thereof.
15. A method of making an elastomeric composite, comprising:
casting a continuous non-foamed elastomeric adhesive film directly onto a first chill roll;
extruding a plurality of continuous elastic strands directly onto the non-foamed film to create a continuous strand-reinforced composite;
stretching the continuous composite as a single unit; and
laminating the stretched composite between a first facing sheet and a second facing sheet.
16. The method of claim 15 , further comprising passing the film onto a second chill roll and extruding the plurality of elastic strands onto the film while the film is in contact with the second chill roll.
17. The method of claim 15 , comprising casting the elastomeric adhesive film from a melt tank onto the first chill roll.
18. The method of claim 15 , comprising casting the elastomeric adhesive film from a supply roll onto the first chill roll.
19. The method of claim 15 , comprising extruding the plurality of elastic strands from a melt tank onto the film.
20. The method of claim 15 , comprising extruding the plurality of elastic strands from an extruder onto the film.
21. The method of claim 15 , comprising extruding the plurality of elastic strands from a supply roll onto the film.
22. A method of making an elastomeric composite laminate, comprising:
casting a continuous non-foamed elastomeric adhesive film directly onto a first chill roll;
passing the continuous non-foamed elastomeric adhesive film onto a second roll;
extruding a plurality of continuous elastic strands directly onto the non-foamed film while the film is on the second roll to create a continuous mutually-reinforced strand/film composite;
stretching the continuous composite as a single unit;
laminating the continuous stretched composite between a first facing sheet and a second facing sheet; and
controlling tension in the elastomeric composite through at least one of: selection of film composition, selection of strand composition, add-on rate, stretching the composite, and combinations thereof.