Fibers of variable wettability and materials containing the fibers
View Patent ↗The present invention is directed to an absorbent material and the fibers therein, having two or more layers including an upper surface layer which has on the outer surface of the layer one or more surface area zones which are more wettable zones and adjacent thereto one or more less wettable zones, where the more wettable zones have a greater hydrophilicity than the less wettable zone. The present invention is also directed to the fibers therein, which contain polyvalent cation-containing compounds and fatty acid containing compounds. The present invention also provides for methods of treating fibers or solid materials and processes of producing the hydrophobic materials.
1. A fibrous material comprising a blend of fibers, wherein the blend of fibers comprises:
(a) cellulosic fibers bound with a dissociating polyvalent cation-containing compound; wherein the polyvalent cation-containing compound is present in an amount from about 0.1 weight percent to about 20 weight percent based on the dry weight of the cellulosic fiber prior to treatment with the bound polyvalent cation-containing compound; and
(b) synthetic fibers coated with a fatty acid containing compound, wherein substantially no polyvalent cation is present on the synthetic fibers; and
wherein the fibrous material is hydrophobic.
2. The fibrous material of claim 1 , wherein the fatty acid containing compound is selected from the group consisting of sodium oleate, methyl oleate, sodium laurate, oleic acid, stearic acid, and mixtures thereof.
3. The fibrous material of claim 1 , wherein the polyvalent cation containing compound is a polyvalent metal ion salt.
4. The fibers of claim 3 , wherein the polyvalent metal is selected from the group consisting of aluminum, iron, tin, and mixtures thereof.
5. The fibers of claim 4 , wherein the polyvalent metal is aluminum.
6. The fibers of claim 3 , wherein the polyvalent salt is selected from the group consisting of aluminum chloride, aluminum hydroxide, aluminum sulfate, and mixtures thereof.
7. The fibrous material of claim 1 , wherein the contact angle of fibers in the blend of fibers is greater than 90°.
8. The fibrous material of claim 1 , further comprising one or more fillers.
9. The fibrous material of claim 1 , wherein the cellulosic fibers are cross linked and optionally treating the fibers with a cross-linking agent.
10. The fibrous material of claim 9 , wherein the cross-linking agent is applied with thermal radiation.