Fragranced water-sensitive film
View Patent ↗A film formed from a water-soluble polymer matrix containing a fragrance is provided. The film is water-sensitive so that upon contact with a sufficient amount of water, the matrix loses its integrity to increasingly expose the fragrance to the ambient environment for releasing its odor. The ability to incorporate a fragrance into the matrix is achieved by controlling the nature of the fragrance and polymer, the manner in which the matrix and fragrance are melt processed, etc. For example, the fragrance may be injected directly into the extruder and melt blended with the polymer to avoid the costly, time-consuming steps of pre-encapsulation or pre-compounding of the fragrance into a masterbatch. Furthermore, to balance the fragrance's ability to release the desired odor during use while minimizing the premature exhaustion of the odor during processing, the fragrance has a boiling point (at atmospheric pressure) of from about 125° C. to about 350° C.
1. A water-sensitive fragranced film formed from a melt-processed blend of:
(1) a first water-soluble polymer, wherein the first water-soluble polymer includes a chemically modified starch, wherein the chemically modified starch is a hydroxyalkyl starch;
(2) a second water-soluble polymer, wherein the second water-soluble polymer is a vinyl alcohol polymer;
(3) a biodegradable polyester, wherein the biodegradable polyester includes an aliphatic-aromatic copolyester;
(4) at least one liquid fragrance; and
(5) a plasticizer, wherein the plasticizer consists of a polyhydric alcohol, and wherein the liquid fragrance has a boiling point at atmospheric pressure of from about 125° C. to about 350° C.
2. An absorbent article comprising the film of claim 1 , wherein the absorbent article comprises a body portion that includes a liquid permeable topsheet, a generally liquid impermeable backsheet, and an absorbent core positioned between the backsheet and the topsheet.
3. A package comprising the film of claim 1 .
4. The film of claim 1 , wherein the vinyl alcohol polymer is a vinyl alcohol homopolymer.
5. The film of claim 1 , wherein the vinyl alcohol polymer has a degree of hydrolysis of from about 80 mole % to about 95 mole %.
6. The film of claim 1 , wherein the fragrance has a boiling point at atmospheric pressure of from about 175° C. to about 250° C.
7. The film of claim 1 , wherein fragrances constitute from about 0.1 wt. % to about 15 wt. % of the film.
8. The film of claim 1 , wherein fragrances constitute from about 1 wt. % to about 5 wt. % of the film.
9. The film of claim 1 , wherein the first water-soluble polymer and the second water-soluble polymer have a solution viscosity of from about 50 to about 800 milliPascal seconds.
10. The film of claim 1 , wherein the first water-soluble polymer and the second water-soluble polymer constitute from about 40 wt. % to about 99.9 wt. % of the film.
11. The film of claim 1 , wherein the film is formed by supplying the water-soluble polymer and plasticizer to an extruder and directly injecting the liquid fragrance into the extruder to form a blend comprising the water-soluble polymer and the fragrance, wherein injection of the liquid fragrance is accomplished without pre-compounding the fragrance.
12. The film of claim 1 , wherein the polyhydric alcohol is a sugar, a sugar alcohol, a polyol, or a combination thereof.
13. The film of claim 1 , wherein the first water-soluble polymer constitutes from 15 wt. % to 56 wt. % of the film.
14. The film of claim 1 , wherein the second water-soluble polymer constitutes from 6 wt. % to 24 wt. % of the film.
15. The film of claim 1 , wherein the biodegradable polyester constitutes from 20 wt. % to 70 wt. % of the film.