阅读说明：本技术 吡罗克酮乙醇胺重结晶 (Piroctone olamine recrystallization ) 是由 A·恩德雷斯 H·梅塔 T·米勒 于 2020-02-17 设计创作，主要内容包括：本发明涉及吡罗克酮乙醇胺的重结晶方法、吡罗克酮乙醇胺晶体的制备方法和可以通过这些方法获得的吡罗克酮乙醇胺晶体。(The present invention relates to a method for recrystallization of piroctone olamine, a method for producing a crystal of piroctone olamine, and a crystal of piroctone olamine obtainable by these methods.)

1. a method for recrystallization of piroctone olamine comprising:

a) dissolving piroctone olamine in an alcoholic solvent, wherein the dissolution is carried out at a dissolution temperature which is a temperature greater than 50 ℃ and less than the boiling point of the alcohol;

b) cooling the solution from the dissolution temperature to a temperature of 1-15 degrees celsius for a period of up to 10 hours, preferably 10 minutes-10 hours;

c) recovering the crystals of piroctone olamine.

2. The process according to claim 1, wherein in a), 1.5-4kg, preferably 2kg, of solvent per kg of piroctone olamine are used.

3. The process according to claim 1 or 2, wherein crystals of piroctone olamine are added to seed.

4. The process of any preceding claim, wherein the cooling is carried out in two steps:

i. in a first cooling step, cooling the solution from the dissolution temperature to a temperature of 20-40 degrees celsius for a first cooling period of up to 5 hours;

cooling the solution from a temperature of 20-40 degrees celsius to a temperature of 1-15 degrees celsius in a second cooling step for a second cooling period of up to 5 hours.

5. The process of any preceding claim, wherein the alcohol is selected from the group consisting of methanol, ethanol, propanol, isopropanol, n-butanol, isobutanol, and mixtures thereof.

6. The process of any preceding claim, wherein the alcohol comprises isopropanol.

7. The process of any preceding claim, wherein the solvent consists of an alcohol and preferably consists of isopropanol.

8. The process of any preceding claim, wherein the dissolution temperature is 60-82.5 degrees celsius, preferably 70-75 degrees celsius.

9. A method for preparing piroctone olamine crystals, which comprises the following steps:

a) dispersing piroctone olamine in an alcohol-containing solvent, wherein the dispersion is carried out at a dispersion temperature which is a temperature greater than 50 ℃ and less than the boiling point of the alcohol;

b) cooling the dispersion from the dispersion temperature to a temperature of 1-15 degrees celsius for a period of up to 15 hours, preferably 10 minutes-15 hours, more preferably 1-12 hours;

c) recovering the crystals of piroctone olamine.

10. The process according to claim 9, wherein in a), 1 to 3kg, preferably 1.0 to 1.5kg, more preferably 1.2 to 1.4kg, especially preferably 1.33kg of solvent per kg of piroctone olamine are used.

11. The process of claim 9 or 10, wherein the cooling is performed in two steps:

i. in a first cooling step, cooling the dispersion from the dispersion temperature to a temperature of 20-40 degrees celsius for a first cooling period of up to 10 hours;

cooling the dispersion from a temperature of 20-40 degrees celsius to a temperature of 1-15 degrees celsius in a second cooling step for a second cooling period of up to 5 hours.

12. The process of any of claims 9-11, wherein the alcohol is selected from the group consisting of methanol, ethanol, propanol, isopropanol, n-butanol, isobutanol, and mixtures thereof.

13. The method of any one of claims 9-12, wherein the alcohol comprises isopropanol.

14. The process of any of claims 9-13, wherein the solvent consists of an alcohol and preferably of isopropanol.

15. The process of any of claims 9-14, wherein the dispersion temperature is 60-82.5 degrees celsius, preferably 70-75 degrees celsius.

16. Crystalline piroctone olamine having an average aspect ratio of greater than 1: 4.

17. Piroctone olamine crystals as claimed in claim 16 having a d greater than 110 microns, preferably greater than 140 microns₅₀。

18. Piroctone olamine crystals as claimed in claim 16 or 17 having a d greater than 30 microns, preferably greater than 50 microns₁₀。

19. Piroctone olamine crystals according to any one of claims 16 to 18, obtainable by a process as defined in any one of claims 1 to 15.

20. Piroctone olamine crystals obtainable by a process as defined in any one of claims 1 to 15.