Microparticles and method of making microparticles

1. A process of preparing a composition comprising a plurality of micro-particles and a dispersion liquid in which said micro-particles are dispersed comprising the steps of:

providing a high energy micro-particle producing machine comprising a micro-particle producing assembly within a cooling system;

providing a combination of dispersion liquid, an active and a wax material at such a temperature that the active and the wax material of the combination is in molten form;

passing said combination into said cooling system whilst said micro-particle producing assembly is operating to disperse said active and said wax material of the combination in molten form in said dispersion liquid then while said micro-particle producing assembly is kept operating, cooling said combination in said cooling system to below the solidification temperature of the micro-particles such that cooling of the combination occurs while said micro-particle producing assembly is operating to disperse said active and said wax components so that cooling occurs at the same time as micro-particle formation to produce a composition comprising a plurality of solid micro-particles dispersed in said dispersion liquid before said micro-particles dispersed in said dispersion liquid leave said cooling system, said micro-particles comprising a wax dispersion matrix with said active dispersed therein.

2. A process according to claim 1 , wherein said high energy micro-particle producing machine further comprises a feeding assembly and means for providing fluid flow communication between said feeding assembly and said micro-particle producing assembly, said high energy micro-particle producing machine further comprising means for opening and closing said fluid flow between said feeding assembly and said micro-particle producing assembly.

3. A process according to claim 2 , wherein said combination of said dispersion liquid, said active and said wax material are provided in said feeding assembly at such a temperature that the active and the wax material are melted with fluid flow between said feeding assembly and said micro-particle producing assembly closed and then said fluid flow is opened.

4. A process according to claim 2 , wherein said feeding assembly comprises heating means for melting or keeping melted said active and said wax material of said combination.

5. A process according to claim 2 , wherein said means for providing fluid flow communication further comprises insulating means for keeping said active and said wax material of said combination melted during flow.

6. A process according to claim 1 , comprising the additional steps of recycling said composition comprising said plurality of micro-particles dispersed in said dispersion liquid through the micro-particle producing assembly one or more times whilst cooling is continued such that said composition comprises further micro-particles resulting from cooling of the composition dispersed in said dispersion liquid.

7. A process according to claim 1 , wherein said composition is diluted with a dilution liquid after said composition has left said high energy micro-particle producing machine for the final time.

8. A process according to claim 7 , wherein said dilution liquid is selected from the group consisting of propylene glycol, a blend of surfactants suitable for use as a laundry detergent base, a blend of surfactants suitable for use as a fabric conditioner, glycerol, water, a combination of water and a surface tension lowering agent and mixtures of two or more thereof.

9. A process according to claim 8 , wherein said dilution liquid is colder than said composition.

10. A process according to claim 1 , wherein said composition is further cooled by a cooled heat exchanger after said composition has left said high energy micro-particle producing machine for the final time.

11. A process according to claim 6 , wherein said a high energy micro-particle producing machine is provided with a temperature regulating assembly for controlling the temperature of said combination as it passes through said micro-particle producing assembly.

12. A process according to claim 11 , wherein said temperature regulating assembly is operated during a first step of operation to hold the temperature of said combination at such a first temperature that said active and said wax material of the combination are kept melted when said combination is passed into said micro-particle producing assembly and then is operated during a second step of operation to hold the temperature of said combination at such a second temperature that said plurality of micro-particles are produced by cooling said combination to a temperature below the solidification temperature of each of said micro-particles before each said micro-particle dispersed in said dispersion liquid leaves said micro-particle producing assembly.

13. A process according to claim 11 , wherein said temperature regulating assembly is a cooling jacket which provides said cooling of said combination to a temperature below the solidification temperature of each of said micro-particles before each said micro-particle leaves said micro-particle producing assembly.

14. A process according to claim 1 , wherein said cooling is provided by introducing additional dispersion liquid into said micro-particle producing assembly at a sufficiently low temperature to cool said combination to a said temperature below said solidification temperature of each of said micro-particles.

15. A process according to claim 1 , wherein said high energy micro-particle producing machine is a colloid mill equipped with a feeding funnel.

16. A process according to claim 15 , wherein said feeding funnel is equipped with an immersion heater and a stirrer.

17. A process according to claim 15 , wherein said colloid mill is equipped with a stopcock downstream from its feeding funnel.

18. A process according to claim 1 , wherein said dispersion liquid is selected from the group consisting of propylene glycol, a blend of surfactants suitable for use as a laundry detergent base, a blend of surfactants suitable for use as a fabric conditioner and glycerol and mixtures of two or more thereof.

19. A process according to claim 18 , wherein said process is an in-line process where said produced composition comprising a plurality of micro-particles dispersed in said dispersion liquid is fed into a line of a further process.

20. A process according to claim 1 , wherein said dispersion liquid comprises a surface tension lowering agent.

21. A process according to claim 20 , wherein said process is a batch process wherein said composition comprising a plurality of solid micro-particles dispersed in said dispersion liquid is collected batch wise as a final product of said process, or an in-line process.

22. A process according to claim 1 , wherein each said micro-particle comprises from 20 to 80 weight percent of said active.

23. A process according to claim 1 , further comprising a step of collecting said plurality of solid micro-particles dispersed in said dispersion liquid as a product of the process.

24. A process according to claim 1 , wherein the active is selected from the group consisting of botanical extracts including essential oils, other perfumes and mixtures of two or more thereof.

25. A process according to claim 1 , wherein each of the wax material and the dispersion matrix of the micro-particle is a C22 fatty alcohol.

26. A process according to claim 1 , wherein said high energy micro-particle producing machine comprising said micro-particle producing assembly is a high energy rotor-stator machine comprising a rotor-stator assembly.

27. A process according to claim 1 , wherein said micro-particle producing assembly comprises an orifice, a means for forcing said combination through said orifice and a surface downstream from said orifice whereby said combination is forced through said orifice to strike said surface at a velocity of at least 300 ft/sec.

28. A process according to claim 27 , wherein said means for forcing said combination through said orifice is a pump.

29. A process according to claim 27 , wherein said surface can withstand pressures of up to 5000 psi.

30. A process according to claim 1 , wherein said high energy micro-particle producing machine comprises a rotating mixing portion and a stationary surface surrounding said rotating mixing portion whereby said rotating mixing portion forces said combination towards said stationary surface with such a force that said combination is accelerated to a velocity of at least 300 ft/sec before striking said surface.

31. The process according to claim 1 , wherein the cooling of said combination in said cooling system occurs at a temperature below 65° C.