Water-soluble film
OwnerAndrew P. Verrall, Solomon E. Brown +1inventors
InventorsAndrew P. Verrall, Solomon E. Brown, Dennis A. Beckholt
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Abstract
A film-forming composition made from a mixture of PVOH, chitosan, an alkali metal or ammonium bisulfite or metabisulfite, and optional ingredients such as plasticizers, antioxidants, UV stabilizers, surfactants, crosslinking agents, lubricants, and extenders, is disclosed. Also disclosed are a method of making a film from the composition, a resulting film, and a packet made from the film and containing a cleaning composition such as a rinse additive. The composition can be formulated to yield an article such as a film which is soluble only below a predetermined pH threshold.
Claims22
A water-soluble film comprising a mixture of PVOH, chitosan present in an amount up to 20 wt %, and an alkali metal or ammonium bisulfite or metabisulfite.
A water-soluble film comprising 50 wt % to 90 wt % PVOH having a degree of hydrolysis in a range of 92% to 98%, 1 wt % to 20 wt % chitosan having a degree of acetylation in a range of about 60% to 65%, and 0.01 wt % to 1 wt % sodium bisulfite, wherein the film is insoluble in water having a pH about 9.3 or greater.
A water-soluble film comprising a mixture of PVOH, chitosan and an alkali metal or ammonium bisulfite or metabisulfite wherein the weight ratio of PVOH to chitosan in a range of about 12:1 to about 3:1
A method of making a water-soluble film, comprising the steps of:
- preparing a solution including PVOH polymer and chitosan;
- adding an alkali metal or ammonium bisulfite or metabisulfite, casting the solution;
- and drying off solvent to thereby obtain a water-soluble polymer film.
Dependencies are inferred from the claim text.