METHOD FOR MANUFACTURING FLEXIBLE POROUS SOLUBLE SOLID SHEET ARTICLES WITH IMPROVED PORE STRUCTURES Russian patent published in 2022 - IPC C08J5/18 B29C44/00 B29C44/22 C11D17/06 C11D1/00 C11D1/83 C11D3/37 A61K8/00 A61Q5/00 

FIELD: polymers.

SUBSTANCE: invention relates to a method for producing a flexible porous soluble solid sheet article. Method includes the following stages: a) preparing a wet pre-mixture containing a water-soluble polymer constituting polyvinyl alcohol, and a surface-active agent selected from the group consisting of anionic surfactants, nonionic surfactants, cationic surfactants, zwitterionic surfactants, amphoteric surfactants, polymer surfactants, or combinations thereof, with a viscosity from 1,000 to 25,000 sP when measured at 40°C and 1 s^-1; b) aerating said wet pre-mixture, forming an aerated wet pre-mixture with a density of 0.05 to 0.5 g/ml; c) shaping a sheet with opposite first and second sides from said aerated wet pre-mixture, and (d) drying said shaped sheet for a drying time from 1 to 60 minutes at 70 to 200°C along the heating direction forming a temperature gradient decreasing from the first to the second side of said shaped sheet. Said heating direction herein is essentially opposite to the direction of gravity for the duration of more than half of the drying time.

EFFECT: creation of a more cost-effective and easily scaled method for manufacturing improved flexible porous soluble sheets, allowing for the production of a flexible porous soluble solid sheet article characterised by improved pore structures ensuring higher water-permeability of the sheet article and faster dissolution of the sheet article in water.

13 cl, 9 dwg, 9 tbl, 2 ex