Rapidly dissolvable polymer films and articles made therefrom
A film-forming composition for use in preparing water-soluble films that are rapidly dissolving under cold water conditions, the composition comprising a water soluble polymer material such as polyvinyl alcohol and a principal solvent, typically diol(s) or derivative of a diol. Films made from the film-forming compositions may be used to encapsulate a variety of compositions for subsequent release into an aqueous medium. Encapsulated compositions can include various laundry detergents and additives, fabric care compositions such as fabric softening compositions and dishwashing detergents among others. When used to encapsulate compositions, the solvent system used in the film-forming composition will have at least one common solvent material as the solvent system used in the encapsulated composition to improve film dissolution and to prevent problems associated with solvent migration.
1. An article of manufacture comprising:
a fabric softener to be released into an aqueous medium;
a water-soluble film comprising a film-forming composition, said water-soluble film encapsulating said releasable composition,
wherein said water-soluble film composition comprises from about 50% to about 99.9% of at least one water-soluble polymer; and
from about 0.1% to about 50% of at least one principal solvent
wherein the film forming composition, when formed into a film comprising a thickness of from about 20 microns to about 100 microns, will dissolve in a beaker of water at a temperature below about 68° F. in less than about 5 minutes with agitation and
wherein the releasable composition and the film forming composition comprise a common principal solvent.
2. The article of claim 1 , wherein the water-soluble polymer comprises a polyvinyl alcohol.
3. The article of claim 1 , wherein the film formed from the film-forming composition will dissolve in a beaker of water at a temperature below about 50° F. in less than about 2 minutes with agitation.
4. The article of claim 1 , wherein the water-soluble polymer comprises a mixture of two water-soluble polymers having disparate molecular weights.
5. The article of claim 4 , wherein the water-soluble polymer comprises a first polymer having a molecular weight greater than about 50,000.
6. The article of claim 4 , wherein the ratio of high to low molecular weight polymers is greater than about 50/50.
7. The article of claim 2 , wherein the polyvinyl alcohol is at least partially hydrolyzed.
8. The article of claim 7 , wherein the polyvinyl alcohol is less than about 90% hydrolyzed.
9. The ice of claim 7 , wherein the polyvinyl alcohol is a mixture of at least two polyvinyl alcohol materials, the two polyvinyl alcohol materials having different levels of hydrolysis.
10. The article of claim 1 , wherein the principal solvent is an alcohol.
11. The article of claim 1 , additionally containing a surfactant.
12. The article of claim 1 , wherein the principal solvent is a diol.
13. The article of claim 12 , wherein the principal solvent is a cyclohexanedimethanol.
14. The article of claim 1 , wherein the principal solvent has a C log P between from about −2 to about 2.6.