Synthetic surfactant-free finish, sheet having synthetic surfactant-free finish, articles having sheet with synthetic surfactant-free finish, and related methods
Nonwoven (and film) topsheet and acquisition/distribution materials treated with a hydrophilic, synthetic surfactant-free finish, absorbent articles for infant or incontinence care that contain these materials, and methods for apply such finishes and/or making such absorbent articles.
1. A hydrophilic, synthetic sheet comprising:
a sheet of synthetic material having a first surface;
where the sheet comprises a hydrophilic finish including molecules of a water-soluble protein dispersed on the first surface;
where the finish includes substantially no synthetic surfactants;
where a 0.5-10% aqueous solution of the water-soluble protein has a surface tension of less than 49 milliNewtons per meter (mN/m); and
the water-soluble protein comprises soy protein isolate.
2. The sheet of claim 1 , wherein the finish does not include synthetic materials capable of reducing the surface tension of water below 50 mN/m.
3. The sheet of claim 1 , wherein the sheet comprises a nonwoven fabric or a film.
4. The sheet of claim 1 , where the sheet is a topsheet of an absorbent article.
5. The sheet of claim 1 , wherein the sheet is a distribution-acquisition layer of an absorbent article.
6. The sheet of claim 1 , wherein the water-soluble protein comprises a thermally-denatured protein.
7. The sheet of claim 1 , wherein a 1.2-10% aqueous solution of the water-soluble protein has a surface tension of less than 49 mN/m.
8. The sheet of claim 1 , wherein at least 0.004 grams of the molecules of the water-soluble protein are dispersed on the sheet for each gram of sheet.
9. A disposable absorbent article comprising:
a topsheet comprising the sheet of claim 1 ;
a backsheet; and
an absorbent core disposed between the topsheet and the backsheet.
10. A disposable absorbent article comprising:
a topsheet;
a distribution-acquisition layer comprising the sheet of claim 1 ;
a backsheet; and
an absorbent core disposed between the distribution-acquisition layer and the backsheet.
11. A method of imparting hydrophilic properties to a sheet of polymeric material, the method comprising:
applying a 0.5-10% aqueous solution of a water-soluble protein having a surface tension of less than 49 milliNewtons per meter (mN/m) to a sheet of polymeric material in an aqueous solution; and
drying the sheet such that at least a portion of the protein is retained on a surface of the sheet;
where the aqueous solution is substantially free of synthetic surfactants; and
where the protein comprises soy protein isolate.
12. A finish for a synthetic nonwoven or film, the finish comprising:
an 0.5-10% aqueous solution of a water-soluble, thermally-denatured protein, the solution having a surface tension less than 49 milliNewtons per meter (mN/m);
where the aqueous solution is substantially free of synthetic surfactants; and
where the protein comprises soy protein isolate.