Biodegradable sanitary articles with higher biobased content
The present invention is directed to sanitary articles such as disposable diapers, adult incontinent pads, feminine hygiene products, and sanitary napkins comprised of biodegradable polymers with higher biobased content. The sanitary articles include a topsheet, an absorbent core, and a backsheet. The topsheet is comprised of biodegradable polyester polyol polymer foam which may be configured to wick liquid away from a wearer's body and may be impregnated with superabsorbent polymer. The absorbent core may be comprised of superabsorbent polymer including a cross-linked and/or partially neutralized polyacrylic acid polymer, cross-linked polyacrylic acids or cross-linked starch-acrylic acid graft polymers. The backsheet may be comprised of poly-lactone polymers having generally hydrophobic characteristics. In preferred embodiments, the polymeric materials comprising the topsheet, absorbent core, and backsheet are formed from raw materials with high biobased content.
1. A biodegradable sanitary article, comprising:
a) a topsheet comprising a biodegradable polyester polyol polymer with a heterogeneous dispersion of a biodegradable superabsorbent polymer retained therein, wherein the biodegradable polyester polyol polymer in the topsheet has pores impregnated with the biodegradable superabsorbent polymer;
b) an absorbent core comprising a biodegradable superabsorbent polymer having an inner side positioned adjacent to and fixed with respect to the topsheet; and,
c) a backsheet comprising a biodegradable poly-lactone polymer positioned adjacent to an outer side of the absorbent core and fixed with respect to the absorbent core.
2. The biodegradable sanitary article of claim 1 , wherein the superabsorbent polymer is dispersed in the topsheet as discrete particles.
3. The biodegradable sanitary article of claim 1 , wherein the topsheet has:
i. an absorbent face positioned adjacent to the absorbent core and a corporeal face on an outward face of the sanitary article; and
ii. a concentration of superabsorbent polymer near the corporeal face that is greater than the concentration of superabsorbent polymer near the absorbent face.
4. The biodegradable sanitary article of claim 2 , wherein the discrete particles have an average diameter of greater than 20 micrometers and less than the average thickness of the topsheet.
5. The biodegradable sanitary article of claim 1 , wherein the biodegradable polyol polyester polymer in the topsheet comprises a foam.
6. The biodegradable sanitary article of claim 1 , wherein 90% of the pores have a mean diameter of at least 20 micrometers and no more than 180 micrometers.
7. The biodegradable sanitary article of claim 1 , wherein the topsheet has an absorbent face positioned adjacent to the absorbent core and a corporeal face on an outward face of the biodegradable sanitary article, and wherein the topsheet comprises at least a first pore region adjacent and proximate to the corporeal face and a second pore region adjacent and proximate to the absorbent face.
8. The biodegradable sanitary article of claim 7 , wherein the first pore region has smaller pore sizes than the second pore region.
9. The biodegradable sanitary article of claim 8 , wherein the second pore region comprises pores having a higher concentration of superabsorbent polymer than the first pore region.
10. The biodegradable sanitary article of claim 1 , wherein the biodegradable poly-lactone polymer in the backsheet has or is modified to have a hydrophobic characteristic.
11. The biodegradable sanitary article of claim 1 , wherein the biodegradable sanitary article comprises one or more elastic members formed from one or more of a biodegradable polyester polyol polymer, a biodegradable polyacrylic acid derivative, and a biodegradable poly-lactone polymer.
12. The biodegradable sanitary article of claim 1 , wherein the biodegradable sanitary article comprises one or more adhesive fasteners formed from one or more of a biodegradable polyester polyol polymer, a biodegradable polyacrylic acid derivative, and a biodegradable poly-lactone polymer.
13. The biodegradable sanitary article of claim 1 , wherein the biodegradable polyester polyol polymer of the topsheet comprises one or more carbonyl, carbonate, acetal, ether, nitrile, urethane, urea, imide, anhydride, phosphate, or cyanocrylate functional groups, or any combination thereof.
14. The biodegradable sanitary article of claim 1 , wherein the biodegradable polyester polyol polymer of the topsheet comprises cross-links between polymer main chains allowing for the formation of pores in a three-dimensional structure.
15. The biodegradable sanitary article of claim 1 , wherein the biodegradable poly-lactone polymer of the backsheet comprises poly-lactone, polybutylene succinate, or polybutylene succinate derivatives, or any combination thereof.
16. The biodegradable sanitary article of claim 1 , wherein the biodegradable superabsorbent polymer of the absorbent core comprises a polymer comprising β-propiolactone monomers.
17. A biodegradable sanitary article, comprising:
a) a topsheet comprising a biodegradable polyester polyol polymer lattice having pores impregnated with a heterogenous dispersion of a biodegradable superabsorbent polymer;
b) an absorbent core comprising a biodegradable superabsorbent polymer having an inner side positioned adjacent to and fixed with respect to the topsheet; and,
c) a backsheet comprising a biodegradable poly-lactone polymer positioned adjacent to an outer side of the absorbent core and fixed with respect to the absorbent core.
18. The biodegradable sanitary article of claim 17 , wherein the topsheet comprises an absorbent face positioned adjacent to the absorbent core and a corporeal face.
19. The biodegradable sanitary article of claim 18 , wherein the topsheet comprises at least a first pore region adjacent and proximate to the corporeal face and a second pore region adjacent and proximate to the absorbent face.
20. The biodegradable sanitary article of claim 19 , wherein the first pore region has smaller pore sizes than the second pore region.
21. The biodegradable sanitary article of claim 20 , wherein the second pore region comprises pores having a higher concentration of superabsorbent polymer than the first pore region.
22. The biodegradable sanitary article of claim 17 , wherein the biodegradable poly-lactone polymer of the backsheet has or is modified to have a hydrophobic characteristic.