IMPROVED WATER-SOLUBLE FILM CONTAINING MIXTURE OF PVA POLYMERS AND PACKETS MADE THEREFROM Russian patent published in 2014 - IPC B65B9/04 B65D65/46 

FIELD: chemistry.

SUBSTANCE: pouch made of a water-soluble film comprises a first hermetically fastened compartment containing a first composition, wherein the first compartment comprises at least one wall which includes a water-soluble film consisting of at least 50 wt % of a water-soluble polyvinyl alcohol (PVA) resin. The PVA resin has average viscosity in the range of 13.5 cP to 20 cP and degree of hydrolysis in the range of 84% to 92%, and also contains a mixture of a first and a second PVA polymer. The first PVA polymer has viscosity in the range of 8 cP to 40 cP and the second PVA polymer has viscosity in the range of 10 cP to 40 cP and the viscosity of the first PVA polymer is less than the viscosity of the second PVA polymer. The film further contains no more than 30 wt % of a PVA polymer having viscosity less than 11 cP. In another version, the pouch comprises a first hermetically fastened compartment containing a first composition and a second hermetically fastened compartment containing a second composition, wherein the second compartment is attached to the first compartment and combined such that they have a common separating wall located inside the pouch. The pouch has at least one wall made of a water-soluble film which is the outer wall of the pouch. The water-soluble film is made as described above and further contains 1 wt % to 40 wt % of a plasticiser and no more than 30 wt % of a PVA polymer, having viscosity less than 11 cP, and is characterised by resin selection index value in the range of 0.255 to 0.315. In yet another version, the pouch made of a water-soluble film comprises a first hermetically fastened compartment containing a first composition, a second hermetically fastened compartment containing a second composition, a third hermetically fastened compartment containing a third composition. Each of the compositions is selected from a group consisting of a liquid, a powder and a combination thereof, and the pouch has at least one outer wall made of a water-soluble film containing: at least 50 wt % of a water-soluble PVA resin, wherein the PVA resin has average viscosity in the range of 13.5 cP to 20 cP and degree of hydrolysis in the range of 84% to 92%, and also contains a mixture of a first and a second PVA polymer, wherein the first PVA polymer has viscosity in the range of 8 cP to 40 cP and the second PVA polymer has viscosity in the range of 10 cP to 40 cP and the viscosity of the first PVA polymer is less than the viscosity of the second PVA polymer, wherein the film contains no more than 30 wt % of a PVA polymer having viscosity less than 11 cP, and is characterised by resin selection index value in the range of 0.255 to 0.315, residual moisture content of at least 4 wt %, water-drop resistance test value of at most 60% and wash-residue test value of at most 4.5.

EFFECT: group of inventions increases solubility, water-drop resistance and improves mechanical properties.

20 cl, 15 tbl