Encapsulation of fluids and solids

{
  "publication_number": "US3928230A",
  "country": "US",
  "kind": "A",
  "title": "Encapsulation of fluids and solids",
  "abstract": "The present invention relates to the microencapsulation, capsule diameter 1 to 500 micron, of fluids and solids and is particularly suitable for the formation of capsules having walls of epoxy and like polymers which, as is known, are inert to most chemicals, are not soluble in or permeable to a wide range of fluids and have high static and flexural strength characteristics.",
  "claims": [
    "1. A PROCESS FOR THE ENCAPSULATION OF FLUIDS AND SOLIDS COMPRISING: DISSOLVING A WATER INSOLUBLE POLYMERISABLE EPOXY MONOMER IN A SOLVENT HAVING A HIGHER AFFINITY FOR WATER THAN FOR THE MONOMER; DISPERSING THE MONOMER SOLUTION IN WATER; DISPERSING IN THE AQUEOUS DISPERSION THE SUBSTANCE TO BE ENCAPSULATED; MIXING INTO THE RESULTING DISPERSION A SOLUTION OF A POLYMERISING AGENT EFFECTIVE TO POLYMERISE SAID EPOXY MONOMER IN THE PRESENCE OF WATER, SAID POLYMERISING AGENT BEING IN A SOLVENT HAVING A HIGHER AFFINITY FOR WATER THAN THE POLYMERISING AGENT; AND CONTINUING THE MIXING UNTIL POLYMERISATION OF THE MONOMER IS SUBSTANTIALLY COMPLETE.",
    "2. A process according to claim 1, in which after the substance to be encapsulated has been added to and dispersed in tHe aqueous monomer solution, the resulting dispersion is allowed to stabilise before the polymerising agent is gradually added.",
    "3. A process according to claim 1, in which the water contains a suspending agent which will assist in maintaining the required degree of dispersion.",
    "4. A process according to claim 3, in which the suspending agent is selected from the group consisting of gelatin, methyl cellulose and acacia.",
    "5. A process according to claim 1, in which the solvent having a higher affinity for water than the monomer consists of at least one of the solvents selected from the group consisting of acetone, diethylene glycol, dioxan, tetrahydrofuran and low molecular weight aliphatic alcohols.",
    "6. A process according to claim 1, in which the polymerising agent is selected from the group consisting of a polyamine and a polyamide.",
    "7. A process according to claim 6, in which the polymerising agent is selected from the group consisting of dicyandiamide, triethylenetetramine, a diethylaminopropylamine and 4,4''-diaminodiphenylmethane.",
    "8. A process according to claim 1, in which the polymerising agent is an adduct of a polyamine and phenolformaldehyde.",
    "9. A process according to claim 8, in which the adduct is selected from the group consisting of isophorone diamine phenol-formaldehyde and trimethyl hexamethylene diamine phenol-formaldehyde.",
    "10. A process according to claim 1, in which the solvent for the polymerising agent consists of at least one of the solvents selected from the group consisting of acetone, diethylene glycol, dioxan, tetrahydrofuran and a low molecular weight aliphatic alcohol.",
    "11. A PROCESS FOR THE ENCAPSULATION OF FLUIDS AND SOLIDS COMPRISING: DISPERSING IN WATER THE SUBSTANCE TO BE ENCAPSULATED; DISSOLVING A WATER INSOLUBLE POLYMERISABLE EPOXY MONOMER IN A SOLVENT HAVING A HIGHER AFFINITY FOR WATER THAN THE MONOMER; DISPERSING THE MONOMER SOLUTION IN THE AQUEOUS DISPERSION OF THE SUBSTANCE; MIXING WITH THE RESULTING DISPERSION OF MONOMER AND SUBSTANCE A SOLUTION OF A POLYMERSING AGENT EFFECTIVE TO POLYMERISE SAID EPOXY MONOMER IN THE PRESENCE OF WATER SAID POLYMERISING AGENT BEING IN A SOLVENT HAVING A HIGHER AFFINITY FOR WATER THAN FOR THE POLYMERISING AGENT; AND CONTINUING THE MIXING UNTIL POLYMERISATION OF THE MONOMER IS COMPLETE.",
    "12. A process according to claim 11, in which after the substance to be encapsulated has been added to and dispersed in the aqueous monomer solution, the resulting dispersion is allowed to stabilise before the polymerising agent is gradually added.",
    "13. A process according to claim 11, in which the water contains a suspendidng agent which will assist in maintaining the required degree of dispersion.",
    "14. A process according to claim 13, in which the suspending agent is selected from the group consisting of gelatin, methyl cellulose and acacia.",
    "15. A process according to claim 11, in which the solvent having a higher affinity for water than the monomer consists of at least one of the solvents selected from the group consisting of acetone, diethylene glycol, dioxan, tetrahydrofuran and low molecular weight aliphatic alcohols.",
    "16. A process according to claim 11, in which the polymerising agent is selected from the group consisting of a polyamine and a polyamide.",
    "17. A process according to claim 11, in which the polymerising agent is selected from the group consisting of dicyandiamide, triethylenetetramine, a diethylaminopropylamine and 4,4''-diaminodiphenylmethane.",
    "18. A process according to claim 11, in which the polymerising agent is an adduct of a polyamine and phenol-formaldehyde.",
    "19. A process according to claim 18, in which the adduct is selected from the group consisting of isophorone diamine phenol-formaldehyde and trimethyl hexamethylene diamine phenol-formaldehyde.",
    "20. A process according to claim 11, in which the solvent for the polymerising agent consists of at least one of the solvents selected fRom the group consisting of acetone, diethylene glycol, dioxan, tetrahydrofuran and a low molecular weight aliphatic alcohol.",
    "21. A process for producing capsules having walls of epoxy material and containing a fluid or solid, which comprises dissolving an epoxy monomer in a solvent having a higher affinity for water than the monomer, dispersing the monomer solution in water, dispersing in the aqueous solution a fluid or solid, mixing with the resulting dispersion a solution of a polymerising agent selected from the group consisting of polyamines, polyamides and adducts of polyamines and phenolformaldehyde in a solvent having a higher affinity for water than the polymerising agent, and continuing the mixing until polymerisation of the monomer is substantially complete.",
    "22. A process according to claim 21, in which the particle size of the dispersed fluid or solid is such that the epoxy polymer walled capsules obtained have diameters from 1 to 500 microns.",
    "23. A process for the encapsulation of fluids and solids comprising dispersing in water the substance to be encapsulated, dissolving an epoxy monomer in a solvent having a higher affinity for water than the monomer, dispersing the monomer solution in the aqueous dispersion of the substance, mixing with the resulting dispersion of monomer and substance a solution of a polymerising agent selected from the group consisting of polyamines, polyamides and polyamine phenolformaldehyde adducts in a solvent having a higher affinity for water than for the polymerising agent, and continuing the mixing until polymerisation of the monomer is complete.",
    "24. The process according to claim 23, in which the particle size of the dispersed fluid or solid is such that the epoxy polymer walled capsules obtained have diameters from 1 to 500 microns.",
    "25. A process for the encapsulation of fluids and solids comprising: dissolving a water insoluble polymerisable epoxy monomer in a solvent having a high affinity for water than for the monomer; dispersing the monomer solution in water; dispersing in the aqueous dispersion the substance to be encapsulated and simultaneously mixing into the dispersion a solution of a polymerising agent effective to polymerise said epoxy monomer in the presence of water, said polymerising agent being in a solvent having a higher affinity for water than the polymerising agent; and continuing the mixing until polymerisation of the monomer is substantially complete.",
    "26. A process for the encapsulation of fluids and solids comprising: dispersing in water the substance to be encapsulated; dissolving a water insoluble polymerisable epoxy monomer in a solvent having a higher affinity for water than the monomer; dispersing the monomer solution in the aqueous dispersion of the substance and simultaneously mixing with the dispersion a solution of a polymerising agent effective to polymerise said epoxy in the presence of water, said polymerising agent being in a solvent having a higher affinity for water than for the polymerising agent; and continuing the mixing until polymerisation of the monomer is complete."
  ],
  "cpc": [
    "C08G 59/18",
    "B01J 13/18",
    "Y10T 428/2987",
    "Y10T 428/2989"
  ],
  "assignees": [
    "MAGNESIUM ELEKTRON LTD"
  ],
  "filing_date": "1973-05-22",
  "publication_date": "1975-12-23",
  "grant_date": "1975-12-23",
  "priority_date": "1970-08-13",
  "application_number": "US-36279473-A",
  "family_id": "27259545",
  "citations": [
    "US3006877A",
    "US3055433A",
    "US3268468A",
    "US3415758A",
    "US3432327A",
    "US3544517A"
  ]
}