Sheet materials containing S-B-S and S-I/B-S copolymers
View Patent ↗A sheet material that includes an elastic component or material (e.g., film, nonwoven web laminated to the elastic component, etc.) is provided. The elastic component is formed from a styrenic block copolymer composition containing from about 10 wt. % to about 90 wt. % of styrene-butadiene-styrene block copolymer; and from about 10 wt % to about 90 wt. % of styrene-isoprene/butadiene-styrene block copolymer. The styrenic block copolymer composition has good viscosity stability during extrusion and thus may be readily formed into an elastic sheet material. The elastic sheet material may be subsequently crosslinked to achieve the desired elastic and mechanical properties.
1. An absorbent article comprising an absorbent core positioned between a substantially liquid-impermeable layer and a liquid-permeable layer, the article defining a front waist section, a rear waist section and an intermediate section interconnecting the front waist section and the rear waist section so that the article can be worn about the torso of a wearer, the article further including a waistband in at least one of the front waist section and the rear waist section and side panels joining the front waist section and the rear waist section, wherein at least a portion of at least one of the waistband or the side panels comprises an elastic film composite, the elastic film composite comprising an elastic film including an elastic composition comprising from about 10 wt. % to about 90 wt. % of styrene-butadiene-styrene block copolymer based upon the total weight of the elastic composition and from about 10 wt. % to about 90 wt. % of styrene-isoprene/butadiene-styrene block copolymer based upon the total weight of the elastic composition, wherein the styrene-butadiene-styrene block copolymer and the styrene-isoprene/butadiene-styrene block copolymer are cross-linked and a fibrous nonwoven facing layer is laminated to the elastic film.
2. The absorbent article of claim 1 , wherein the elastic composition comprises from about 25 wt. % to about 75 wt. % of styrene-butadiene-styrene block copolymer based upon the total weight of the elastic composition and from about 25 wt. % to about 75 wt. % of styrene-isoprene/butadiene-styrene block copolymer based upon the total weight of the elastic composition.
3. The absorbent article of claim 1 , wherein the elastic composition comprises from about 25 wt. % to about 50 wt. % of styrene-butadiene-styrene block copolymer based upon the total weight of the elastic composition and from about 50 wt. % to about 75 wt. % of styrene-isoprene/butadiene-styrene block copolymer based upon the total weight of the elastic composition.
4. The absorbent article of claim 1 , wherein the side panels joining the front waist section and the rear waist section further include fastening means for releasably fastening the front waist section and the rear waist section.
5. The absorbent article of claim 4 , wherein the absorbent article is a diaper.
6. The absorbent article of claim 1 , wherein the absorbent article is a training pant.
7. The absorbent article of claim 1 , wherein the absorbent article is an absorbent underpant.
8. The absorbent article of claim 1 , wherein the absorbent article is an adult incontinence product.