Water disintegratable leakproof sheet

Patent metadata

Field	Value
Publication number	US-9295589-B2
Application number	US-201214008642-A
Country	US
Kind code	B2
Filing date	Feb 27, 2012
Priority date	Mar 29, 2011
Publication date	Mar 29, 2016
Grant date	Mar 29, 2016

Abstract

A water disintegratable leak-proof sheet for an absorbent article that has an excellent leak-proof property during wear and excellent water disintegrating property after disposal. The water disintegratable leak-proof sheet of the present disclosure has the following construction. A water disintegratable leak-proof sheet for an absorbent article comprising a water disintegratable base material layer and a water-insoluble and biodegradable resin layer on the water disintegratable base material layer, wherein the tearing strength in the planar direction of the water disintegratable leak-proof sheet is no greater than 0.15 N/40 mm in both a first direction and a second direction perpendicular to the first direction.

First claim

The invention claimed is:

1. A water disintegratable leak-proof sheet for an absorbent article comprising a water disintegratable base material layer and a water-insoluble and biodegradable resin layer on the water disintegratable base material layer,
wherein the water disintegratable leak-proof sheet has a tearing strength in a planar direction of no greater than 0.15 N/40 mm in both a first direction and a second direction perpendicular to the first direction as measured in accordance with JIS K 6772:1994 7.5, and
the water-insoluble and biodegradable resin layer is formed from polylactic acid, and the water disintegratable base material layer is formed from water disintegratable tissue wherein the water-insoluble and biodegradable resin layer comprises regions of low thickness and regions of high thickness, and the water disintegratable base layer comprises regions of low thickness and regions of high thickness, wherein regions of low thickness in the water-insoluble and biodegradable resin layer correspond to regions of high thickness in the water disintegratable base layer, and regions of high thickness in the water-insoluble and biodegradable resin layer correspond to regions of low thickness in the water disintegratable base layer.

2. The water disintegratable leak-proof sheet according to claim 1 , wherein the water disintegratable leak-proof sheet has a water pressure resistance from a side of the water-insoluble and biodegradable resin layer of at least 300 mm.

3. The water disintegratable leak-proof sheet according to claim 1 , wherein the water disintegratable leak-proof sheet has a water pressure resistance from a side of the water-insoluble and biodegradable resin layer after 3 hours of storage under conditions with a temperature of 36° C. and a relative humidity of 90% of at least 300 mm.

4. The water disintegratable leak-proof sheet according to claim 1 , wherein the water disintegratable leak-proof sheet has a dispersion ratio after 48 hours in a shake-flask test of 50 mass % or greater.

5. The water disintegratable leak-proof sheet according to claim 1 , wherein the water-insoluble and biodegradable resin layer has a film thickness in the range of 5 to 18 μm, and the water disintegratable base material has a basis weight in the range of 5-25 g/m 2 .

6. The water disintegratable leak-proof sheet according to claim 1 , wherein the water disintegratable leak-proof sheet is formed by melting the water-insoluble and biodegradable resin layer on the water disintegratable base material layer.

7. An absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet and an absorbent body between the liquid-permeable top sheet and liquid-impermeable back sheet, wherein the liquid-impermeable back sheet is formed from the water disintegratable leak-proof sheet according to claim 1 .

8. The water disintegratable leak-proof sheet according to claim 2 , wherein the water disintegratable leak-proof sheet has a dispersion ratio after 48 hours in a shake-flask test of 50 mass % or greater.

9. The water disintegratable leak-proof sheet according to claim 3 , wherein the water disintegratable leak-proof sheet has a dispersion ratio after 48 hours in a shake-flask test of 50 mass % or greater.

10. The water disintegratable leak-proof sheet according to claim 2 , wherein the water-insoluble and biodegradable resin layer has a film thickness in the range of 5 to 18 μm, and the water disintegratable base material has a basis weight in the range of 5-25 g/m 2 .

11. The water disintegratable leak-proof sheet according to claim 3 , wherein the water-insoluble and biodegradable resin layer has a film thickness in the range of 5 to 18 μm, and the water disintegratable base material has a basis weight in the range of 5-25 g/m 2 .

12. The water disintegratable leak-proof sheet according to claim 4 , wherein the water-insoluble and biodegradable resin layer has a film thickness in the range of 5 to 18 μm, and the water disintegratable base material has a basis weight in the range of 5-25 g/m 2 .

13. The water disintegratable leak-proof sheet according to claim 9 , wherein the water-insoluble and biodegradable resin layer has a film thickness in the range of 5 to 18 μm, and the water disintegratable base material has a basis weight in the range of 5-25 g/m 2 .

14. The water disintegratable leak-proof sheet according to claim 2 , wherein the water disintegratable leak-proof sheet is formed by melting the water-insoluble and biodegradable resin layer on the water disintegratable base material layer.

15. The water disintegratable leak-proof sheet according to claim 3 , wherein the water disintegratable leak-proof sheet is formed by melting the water-insoluble and biodegradable resin layer on the water disintegratable base material layer.

16. The water disintegratable leak-proof sheet according to claim 4 , wherein the water disintegratable leak-proof sheet is formed by melting the water-insoluble and biodegradable resin layer on the water disintegratable base material layer.

17. The water disintegratable leak-proof sheet according to claim 5 , wherein the water disintegratable leak-proof sheet is formed by melting the water-insoluble and biodegradable resin layer on the water disintegratable base material layer.

Assignees

• Konishi Takayoshi
• Yamaki Koichi
• Matsushima Azusa
• Unicharm Corp

Inventors

• Konishi Takayoshi
• Yamaki Koichi
• Matsushima Azusa

Classifications

• A61F13/51401

  characterised by the material · CPC title

• A61F13/51478

  being a laminate, e.g. multi-layered or with several layers · CPC title

• A61F13/15211 Primary

  soluble or disintegratable in liquid · CPC title

• A61F2013/51433

  being biodegradable · CPC title