Water soluble package and for producing it
Use of a poly(vinyl alcohol) (PVOH) sheet having a water content of at least 5 wt % and a thickness of at least 200 μm as a substrate having a reduced tendency to shrink back as compared to the same PVOH having a lower thickness in a thermoforming process to produce a pocket in a mould.
1 . A method of thermoforming a pocket in a mould which method comprises the step of: using poly(vinyl alcohol) (PVOH) sheet having a thickness of at least 200 μm, wherein the PVOH sheet has a water content of at least 5 wt % as a substrate having a reduced tendency to shrink back as compared with the same PVOH having a smaller thickness.
2 . A method according to claim 1 , wherein the PVOH sheet has a thickness of 300 to 1000 μm.
3 . A method according to claim 2 , wherein the PVOH sheet has a thickness of 400 to 600 μm.
4 . A method according to claim 1 , wherein the PVOH sheet is soluble in water at a temperature of 20° C.
5 . A method according to claim 1 wherein the pocket is filled with a composition, a top film is placed on top of the filed pocket and the PVOH sheet and the top film are sealed together to form a container containing the composition.
6 . A method according to claim 1 wherein, the pocket is divided into a plurality of separate portions.
7 . A method according to claim 5 , wherein the container is soluble in water at a temperature of 20° C.
8 . A method according to claim 5 , wherein the composition is a liquid or particulate composition.
9 . A method according to claim 5 , wherein the composition is a fabric care, surface care or dishwashing composition.
10 . A method according to claim 9 , wherein the composition is a dishwashing, water-softening, laundry or detergent composition or a rinse aid.
11 . A method according to claim 6 , wherein the composition is a disinfectant, antibacterial or antiseptic composition.
12 . A method according to claim 6 , wherein the composition is a refill composition for a trigger-type spray.
13 . A process for the manufacture of a rigid pocket from a rigid sheet, wherein the process comprises forming the rigid sheet in a thermo-shaping process and thermoforming the sheet into a rigid pocket.
14 . A process according to claim 13 , wherein the thermo-shaping process comprises calendering or die casting.
15 . A process according to claim 13 , wherein the sheet comprises PVOH.
16 . A process according to claim 15 , wherein the PVOH sheet has a thickness of 300 to 1000 μm.
17 . A process according to claim 14 , wherein the PVOH sheet is soluble in water at a temperature of 20° C.
18 . A process according to claim 13 , wherein the pocket is filled with a composition, a top film is placed on top of the filed pocket and the PVOH sheet and the top film are sealed together to form a container containing the composition.
19 . A process according to claim 13 , wherein the pocket is divided into a plurality of separate portions.
20 . A process according to claim 18 , wherein the pocket is soluble in water at a temperature of 20° C.
21 . A process according to claim 18 , wherein the composition is a liquid or particulate composition.
22 . A process according to claim 18 , wherein the composition is a fabric care, surface care or dishwashing composition.
23 . A process according to claim 22 , wherein the composition is a dishwashing, water-softening, laundry or detergent composition or a rinse aid.
24 . A process according to claim 18 , wherein the composition is a disinfectant, antibacterial or antiseptic composition.