Freeze-drying mold and method for manufacturing water-soluble polymer ball using same

A method for manufacturing a hyaluronic acid-based water-soluble polymer balls using a freeze-drying mold for a water-soluble polymer and hyaluronic acid-based water-soluble polymer solution,

• wherein the freeze-drying mold for a water-soluble polymer has a first mold and a second mold,
• wherein the first mold has a fitting portion steppedly protruding from the underside thereof, a plurality of first hemispherical accommodation grooves formed on the surface of the fitting portion in the form of a lattice, and a plurality of discharge portions formed on top thereof to communicate with the plurality of first accommodation grooves;
• wherein the second mold has a fitting recess concavedly formed on top thereof to be coupled to the fitting portion and a plurality of second hemispherical accommodation grooves formed on top thereof in the form of a lattice to be facingly coupled to the plurality of first accommodation grooves of the first mold to thus provide a plurality of spherical accommodation portions;
• wherein the first mold and the second mold have at least one or more fastening holes formed thereon correspondingly to one another and thus coupled to one another by means of fastening members,
• wherein the first mold has a lower thermal conductivity than the second mold,
• wherein the second mold includes a coating layer using the same material as the first mold, and
• wherein the method for manufacturing the hyaluronic acid-based water-soluble polymer balls comprises steps of:
• coupling the first mold having the plurality of first hemispherical accommodation grooves formed on the underside thereof and the plurality of discharge portions formed on top thereof to communicate with the plurality of first hemispherical accommodation grooves to the second mold having the plurality of second accommodation grooves formed on top thereof to be facingly coupled to the plurality of first hemispherical accommodation grooves to thus provide the plurality of spherical accommodation portions;
• heating and agitating the hyaluronic acid-based water-soluble polymer solution at a temperature in the range of 5 to 50° C.;
• a first freezing step of freezing the hyaluronic acid-based water-soluble polymer solution at an atmospheric pressure and a temperature in the range of −3 to −8° C. for 20 to 40 minutes;
• a second freezing step of reducing the hyaluronic acid-based water-soluble polymer solution after the first freezing step to a temperature in the range of −40 to −50° C. at the atmospheric pressure for 5 to 9 hours;
• and a third freezing step of keeping the hyaluronic acid-based water-soluble polymer solution after the second freezing step to a temperature in the range of −40 to −50° C. at the atmospheric pressure for 1 to 3 hours;
• a first drying step of step by step or sequentially raising the frozen hyaluronic acid-based water-soluble polymer solution at a pressure in the range of 100 to 1,000 pbar to a temperature in the range of 10 to 40° C. for 5 to 30 hours;
• and a second drying step of drying the water-soluble polymer solution after the first drying step at a pressure in the range of 1 to 99 pbar and a temperature in the range of 20 to 50° C. for 1 to 20 hours;
• and separating the first mold and the second mold from each other to collect the hyaluronic acid-based water-soluble polymer balls having a dissolving time in water within 20 seconds.