US4285720A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Encapsulation process and capsules produced thereby
Assignee: Zeneca Inc
•
Filing: 1978-07-07
•
Granted: 1981-08-25
•
Expires: 1998-07-07
Abstract
Abstract Encapsulation process to prepare encapsulated water-immiscible material employing an organic polyisocyanate intermediate to form a polyurea capsule enclosure around a water-immiscible material dispersed in an aqueous continuous phase comprising the steps of heating the dispersion or adding a catalyst, and optionally adjusting the pH to a value between 0 and 14.
Inventors
- 👤 Herbert B. Scher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:40
CPC Classifications
B; B01; B01J; B01J13/00; B01J13/02; B01J13/06; B01J13/14; B01J13/16; A; A01; A01N; A01N25/00; A01N25/26; A01N25/28; C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/30; C08G18/302; Y; Y10; Y10S; Y10S424/00; Y10S424/08
Claims Analysis
Total Claims: 111
Claim 1
Independent Claim
120 words
A process of encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing, at room temperature, a dispersion of (i) a water-immiscible phase comprising the water-immiscible material to be encapsulated and an organic polyisocyanate in (ii) an aqueous phase comprising a solution of water, a surfactant and a protective colloid; and (b) heating and maintaining said dispersion in a temperature range of about 40° C. to about 90° C.; whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 2
Dependent Claim
120 words
A process of encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing, at room temperature, a dispersion of (i) a water-immiscible phase comprising the water-immiscible material to be encapsulated and an organic polyisocyanate in (ii) an aqueous phase comprising a solution of water, a surfactant and a protective colloid; and (b) heating and maintaining said dispersion in a temperature range of about 40° C. to about 90° C.; whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 3
Dependent Claim
25 words
The process of claim 1 wherein the dispersed water-immiscible phase comprises droplets having a particle size of between about 0.5 microns to about 4000 microns.
Claim 4
Dependent Claim
13 words
The process of claim 2 wherein said dispersion is maintained by mild agitation.
Claim 5
Dependent Claim
68 words
The process of claim 3, wherein said water-immiscible phase contains a catalyst selected from the group consisting of (a) a basic organic tertiary amine catalyst in the amount of about 0.01 percent to about 10.0 percent by weight based on the organic phase and (b) an alkyl tin acetate catalyst in the amount of about 0.001 percent to about 1.0 percent by weight based on the organic phase.
Claim 6
Dependent Claim
26 words
The process of claim 3 wherein said dispersion includes a catalyst capable of increasing the rate of reaction of said organic polyisocyanate to form said polyurea.
Claim 7
Dependent Claim
27 words
The process of claim 5 wherein said catalyst is selected from the group consisting of a basic organic tertiary amine catalyst and an alkyl tin acetate catalyst.
Claim 8
Dependent Claim
26 words
The process of claim 1 wherein said dispersion includes a catalyst capable of increasing the rate of reaction of said organic polyisocyanate to form said polyurea.
Claim 9
Dependent Claim
27 words
The process of claim 7 wherein said catalyst is selected from the group consisting of a basic organic tertiary amine catalyst and an alkyl tin acetate catalyst.
Claim 10
Dependent Claim
68 words
The process of claim 1 wherein said water-immiscible phase contains a catalyst selected from the group consisting of (a) a basic organic tertiary amine catalyst in the amount of about 0.01 percent to about 10.0 percent by weight based on the organic phase and (b) an alkyl tin acetate catalyst in the amount of about 0.001 percent to about 1.0 percent by weight based on the organic phase.
Claim 11
Dependent Claim
25 words
Capsules capable of controlled release of encapsulated organic material comprising a thiocarbamate herbicide enclosed in a polyurea capsule produced by the process of claim 9.
Claim 12
Dependent Claim
25 words
Capsules capable of controlled release of encapsulated organic material comprising an organophosphorus insecticide enclosed in a polyurea capsule produced by the process of claim 9.
Claim 13
Dependent Claim
26 words
Capsules capable of controlled release of encapsulated organic material comprising an insect hormone mimic enclosed in a polyurea capsule produced by the process of claim 9.
Claim 14
Dependent Claim
12 words
The process of claim 1 wherein said organic polyisocyanate is aromatic diisocyanate.
Claim 15
Dependent Claim
24 words
The process of claim 13 wherein said aromatic diisocyanate comprises from about 2.0 percent to about 75.0 percent by weight of said water-immiscible phase.
Claim 16
Dependent Claim
20 words
The process of claim 13 wherein said aromatic diisocyanate is 80 percent 2,4- and 20 percent 2,6-isomer of tolylene diisocyanate.
Claim 17
Dependent Claim
13 words
The process of claim 1 wherein said water-immiscible material is water-immiscible organic material.
Claim 18
Dependent Claim
14 words
The process of claim 16 wherein said water-immiscible organic material is a thiocarbamate herbicide.
Claim 19
Dependent Claim
17 words
The process of claim 16 wherein said water-immiscible organic material comprises at least two water-immiscible organic materials.
Claim 20
Dependent Claim
18 words
The process of claim 18 wherein said water-immiscible organic material comprises a thiocarbamate herbicide and an antidote therefor.
Claim 21
Dependent Claim
14 words
The process of claim 16 wherein said water-immiscible organic material is an organophosphorous insecticide.
Claim 22
Dependent Claim
15 words
The process of claim 16 wherein said water-immiscible organic material is an insect hormone mimic.
Claim 23
Dependent Claim
24 words
The process of claim 1 wherein said dispersion is heated and maintained in a temperature range of about 40° C. to about 60° C.
Claim 24
Dependent Claim
25 words
Capsules capable of controlled release of encapsulated organic material comprising a thiocarbamate herbicide enclosed in a polyurea microcapsule produced by the process of claim 1.
Claim 25
Dependent Claim
12 words
Capsules of claim 23 in which said thiocarbamate herbicide is S-ethyl diisobutylthiocarbamate.
Claim 26
Dependent Claim
12 words
Capsules of claim 23 in which said thiocarbamate herbicide is S-ethyl dipropylthiocarbamate.
Claim 27
Dependent Claim
12 words
Capsules of claim 23 in which said thiocarbamate herbicide is S-ethyl hexahydro-1-H-azepine-1-carbothioate.
Claim 28
Dependent Claim
12 words
Capsules of claim 23 in which said thiocarbamate herbicide is S-propyl dipropylthiocarbamate.
Claim 29
Dependent Claim
12 words
Capsules of claim 23 in which said thiocarbamate herbicide is S-ethyl ethylcyclohexylthiocarbamate.
Claim 30
Dependent Claim
12 words
Capsules of claim 23 in which said thiocarbamate herbicide is S-propyl butylethylthiocarbamate.
Claim 31
Dependent Claim
12 words
Capsules of claim 23 in which said thiocarbamate herbicide is S-propyl hexahydro-1-H-azepine-1-carbothioate.
Claim 32
Dependent Claim
25 words
Capsules capable of controlled release of encapsulated organic material comprising an organophosphorus insecticide enclosed in a polyurea capsule produced by the process of claim 1.
Claim 33
Dependent Claim
13 words
Capsules of claim 1 in which said organophosphorus insecticide is O-ethyl S-phenyl ethylphosphonodithioate.
Claim 34
Dependent Claim
13 words
Capsules of claim 31 in which said organophosphorus insecticide is S[(p-chlorophenylthio)methyl] O,O-dimethyl phosphorodithioate.
Claim 35
Dependent Claim
13 words
Capsules of claim 31 in which said organophosphorus insecticide is S[(p-chlorophenylthio)methyl] O,O-diethyl phosphorodithioate.
Claim 36
Dependent Claim
13 words
Capsules of claim 31 in which said organophosphorus insecticide is O,O-dimethyl O-p-nitrophenyl phosphorothioate.
Claim 37
Dependent Claim
13 words
Capsules of claim 31 in which said organophosphorus insecticide is O,O-diethyl O-p-nitrophenyl phosphorothioate.
Claim 38
Dependent Claim
26 words
Capsules capable of controlled release of encapsulated organic material comprising an insect hormone mimic enclosed in a polyurea capsule produced by the process of claim 1.
Claim 39
Dependent Claim
12 words
Capsules of claim 37 in which said insect hormone mimic is 1-(4'-ethyl)phenoxy-3,7-dimethyl-6,7-epoxy-trans-2-octene.
Claim 40
Dependent Claim
136 words
A process of encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing in an aqueous phase at room temperature a solution comprising water, a surfactant and a protective colloid; (b) adding to said aqueous phase a water-immiscible phase comprising the water-immiscible material to be encapsulated and an organic polyisocyanate; (c) dispersing at room temperature said water-immiscible phase in said aqueous phase; (d) heating and maintaining the dispersed water-immiscible phase and aqueous phase in a temperature range of about 40° C. to about 90° C.; whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 41
Dependent Claim
136 words
A process of encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing in an aqueous phase at room temperature a solution comprising water, a surfactant and a protective colloid; (b) adding to said aqueous phase a water-immiscible phase comprising the water-immiscible material to be encapsulated and an organic polyisocyanate; (c) dispersing at room temperature said water-immiscible phase in said aqueous phase; (d) heating and maintaining the dispersed water-immiscible phase and aqueous phase in a temperature range of about 40° C. to about 90° C.; whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 42
Dependent Claim
25 words
The process of claim 39 wherein the dispersed water-immiscible phase comprises droplets having a particle size of between about 0.5 microns to about 4000 microns.
Claim 43
Dependent Claim
13 words
The process of claim 40 wherein said dispersion is maintained by mild agitation.
Claim 44
Dependent Claim
14 words
The process of claim 39 in which said water-immiscible material is water-immiscible organic material.
Claim 45
Dependent Claim
35 words
The process of claim 42 for encapsulating water-immiscible organic material wherein the water-immiscible phase added to the aqueous phase contains organic polyisocyanate within the range of about 2.0 percent to about 75.0 percent by weight.
Claim 46
Dependent Claim
17 words
The process of claim 43 for encapsulating water-immiscible organic material wherein said organic polyisocyanate is aromatic polyisocyanate.
Claim 47
Dependent Claim
17 words
The process of claim 44 for encapsulating water-immiscible organic material wherein said aromatic polyisocyanate is polymethylene polyphenylisocyanate.
Claim 48
Dependent Claim
18 words
The process of claim 43 for encapsulating water-immiscible organic material wherein said organic polyisocyanate is an aromatic diisocyanate.
Claim 49
Dependent Claim
25 words
The process of claim 46 for encapsulating water-immiscible organic material wherein said aromatic diisocyanate is 80 percent 2,4- and 20 percent 2,6-isomer of tolylene diisocyanate.
Claim 50
Dependent Claim
44 words
The process of claim 42 for encapsulating water-immiscible organic material wherein the water-immiscible phase added to the aqueous phase contains a combination of organic polyisocyanates, the total amount of which is within the range of about 2.0 percent to about 75 percent by weight.
Claim 51
Dependent Claim
26 words
The process of claim 48 wherein said combination of organic polyisocyanates consists of polymethylene polyphenylisocyanate and 80 percent 2,4- and 20 percent 2,6-isomers of tolylene diisocyanate.
Claim 52
Dependent Claim
24 words
The process of claim 39 further comprising the step of adjusting the pH of said aqueous phase to a value between 0 and 14.
Claim 53
Dependent Claim
25 words
The process of claim 42 wherein said water-immiscible organic material is a thiocarbamate herbicide; whereupon said thiocarbamate herbicide is encapsulated within a polyurea capsular enclosure.
Claim 54
Dependent Claim
21 words
The process of claim 51 for encapsulating water-immiscible organic material within a polyurea capsule wherein said thiocarbamate herbicide is S-ethyl diisobutylthiocarbamate.
Claim 55
Dependent Claim
22 words
The process of claim 51 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said thiocarbamate herbicide is S-ethyl dipropylthiocarbamate.
Claim 56
Dependent Claim
22 words
The process of claim 51 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said thiocarbamate herbicide is S-ethyl hexahydro-1-H-azepine-1-carbothioate.
Claim 57
Dependent Claim
22 words
The process of claim 51 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said thiocarbamate herbicide is S-propyl dipropyl-thiocarbamate.
Claim 58
Dependent Claim
22 words
The process of claim 51 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said thiocarbamate herbicide is S-ethyl ethylcyclohexylthiocarbamate.
Claim 59
Dependent Claim
22 words
The process of claim 51 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said thiocarbamate herbicide is S-propyl butylethylthiocarbamate.
Claim 60
Dependent Claim
22 words
The process of claim 51 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said thiocarbamate herbicide is S-propyl hexahydro-1-H-azepine-1-carbothioate.
Claim 61
Dependent Claim
25 words
The process of claim 42 wherein said water-immiscible organic material is an organophosphorus insecticide, whereupon said organophosphorus insecticide is encapsulated within a polyurea capsular enclosure.
Claim 62
Dependent Claim
23 words
The process of claim 59 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said organophosphorus insecticide is O-ethyl S-phenyl ethylphosphonodithioate.
Claim 63
Dependent Claim
23 words
The process of claim 59 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said organophosphorus insecticide is O,O-dimethyl O-p-nitrophenyl phosphorothioate.
Claim 64
Dependent Claim
23 words
The process of claim 59 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said organophosphorus insecticide is O,O-diethyl O-p-nitrophenyl phosphorothioate.
Claim 65
Dependent Claim
22 words
The process of claim 59 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said organophosphorus insecticide is S-[(p-chlorophenylthio)methyl]O,O-dimethyl phosphorodithioate.
Claim 66
Dependent Claim
23 words
The process of claim 59 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said organophosphorus insecticide is S-[(p-chlorophenylthio)methyl] O,O-diethyl phosphorodiothioate.
Claim 67
Dependent Claim
27 words
The process of claim 42 wherein said water-immiscible organic material is an insect hormone mimic, whereupon said insect hormone mimic is encapsulated within a polyurea capsular enclosure.
Claim 68
Dependent Claim
22 words
The process of claim 65 for encapsulating a water-immiscible organic material within a polyurea capsule wherein said insect hormone mimic is 1-(4'-ethyl)phenoxy-3,7-dimethyl-6,7-epoxy-trans-2-octene.
Claim 69
Dependent Claim
31 words
The process of claim 42 wherein said water-immiscible organic material comprises at least two water-immiscible materials in the organic phase; whereupon said water-immiscible materials are encapsulated within a polyurea capsular enclosure.
Claim 70
Dependent Claim
17 words
The process of claim 67 wherein said water-immiscible materials are a thiocarbamate herbicide and an antidote therefor.
Claim 71
Dependent Claim
18 words
The process of claim 68 in which said thiocarbamate herbicide is S-ethyl dipropylthiocarbamate and said antidote is N,N-diallyldichloroacetamide.
Claim 72
Dependent Claim
29 words
The process of claim 39 wherein said dispersed water-immiscible phase and aqueous phase is heated and maintained in a temperature range of about 40° C. to about 60° C.
Claim 73
Dependent Claim
27 words
The process of claim 39 wherein said water-immiscible phase contains a catalyst capable of increasing the rate of reaction of said organic polyisocyanate to form said polyurea.
Claim 74
Dependent Claim
27 words
The process of claim 71 wherein said catalyst is selected from the group consisting of a basic organic tertiary amine catalyst and an alkyl tin acetate catalyst.
Claim 75
Dependent Claim
25 words
Capsules capable of controlled release of encapsulated organic material comprising a thiocarbamate herbicide enclosed in a polyurea capsule produced by the process of claim 39.
Claim 76
Dependent Claim
25 words
Capsules capable of controlled release of encapsulated organic material comprising an organophosphorus insecticide enclosed in a polyurea capsule produced by the process of claim 39.
Claim 77
Dependent Claim
26 words
Capsules capable of controlled release of encapsulated organic material comprising an insect hormone mimic enclosed in a polyurea capsule produced by the process of claim 39.
Claim 78
Dependent Claim
153 words
A process of encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing in an aqueous phase at room temperature a solution comprising water and a surfactant; (b) adding to said aqueous phase a water-immiscible phase comprising a water-immiscible material to be encapsulated and an organic polyisocyanate; (c) dispersing at room temperature said water-immiscible phase in said aqueous phase to form a dispersion of droplets of the water-immiscible phase in said aqueous phase; (d) adding to said dispersion a protective colloid; (e) heating and maintaining said dispersion in a temperature range of about 40° C. to about 90° C. with mild agitation; whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 79
Dependent Claim
153 words
A process of encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing in an aqueous phase at room temperature a solution comprising water and a surfactant; (b) adding to said aqueous phase a water-immiscible phase comprising a water-immiscible material to be encapsulated and an organic polyisocyanate; (c) dispersing at room temperature said water-immiscible phase in said aqueous phase to form a dispersion of droplets of the water-immiscible phase in said aqueous phase; (d) adding to said dispersion a protective colloid; (e) heating and maintaining said dispersion in a temperature range of about 40° C. to about 90° C. with mild agitation; whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 80
Dependent Claim
17 words
The process of claim 76 wherein the temperature range is about 40° C. to about 60° C.
Claim 81
Dependent Claim
26 words
The process of claim 76 wherein the dispersion contains a catalyst capable of increasing the rate of reaction of said organic polyisocyanate to form said polyurea.
Claim 82
Dependent Claim
129 words
A process of encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing, at room temperature, a dispersion comprising (i) a water-immiscible phase comprising the water-immiscible material to be encapsulated and an organic polyisocyanate in (ii) an aqueous phase comprising a solution of water, a surfactant and a protective colloid, which dispersion contains a catalyst capable of increasing the rate of reaction of said organic polyisocyanate to form said polyurea; and (b) maintaining said dispersion at room temperature whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 83
Dependent Claim
129 words
A process of encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing, at room temperature, a dispersion comprising (i) a water-immiscible phase comprising the water-immiscible material to be encapsulated and an organic polyisocyanate in (ii) an aqueous phase comprising a solution of water, a surfactant and a protective colloid, which dispersion contains a catalyst capable of increasing the rate of reaction of said organic polyisocyanate to form said polyurea; and (b) maintaining said dispersion at room temperature whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 84
Dependent Claim
25 words
The process of claim 79 wherein the dispersed water-immiscible phase comprises droplets having a particle size of between about 0.5 microns to about 4000 microns.
Claim 85
Dependent Claim
13 words
The process of claim 79 wherein said dispersion is maintained by mild agitation.
Claim 86
Dependent Claim
27 words
The process of claim 79 wherein said catalyst is selected from the group consisting of a basic organic tertiary amine catalyst and an alkyl tin acetate catalyst.
Claim 87
Dependent Claim
65 words
The process of claim 79 wherein said catalyst is selected from the group consisting of (a) a basic organic tertiary amine catalyst in the amount of about 0.01 percent to about 10.0 percent by weight based on the organic phase and (b) an alkyl tin acetate catalyst in the amount of about 0.001 percent to about 1.0 percent by weight based on the organic phase.
Claim 88
Dependent Claim
33 words
The process of claim 79 wherein said catalyst is a basic organic tertiary amine catalyst in the amount of about 0.01 percent to about 10.0 percent by weight based on the organic phase.
Claim 89
Dependent Claim
23 words
The process of claim 84 wherein said catalyst is selected from the group consisting of triethylene diamine, N,N,N',N'-tetramethyl-1,3-butane diamine, triethylamine and tri-n-butyl amine.
Claim 90
Dependent Claim
32 words
The process of claim 79 wherein said catalyst is an alkyl tin acetate catalyst in the amount of about 0.001 percent to about 1.0 percent by weight based on the organic phase.
Claim 91
Dependent Claim
22 words
The process of claim 86 wherein said catalyst is selected from the group consisting of tri-butyl tin acetate and di-n-butyl tin diacetate.
Claim 92
Dependent Claim
21 words
The process of claim 79 wherein the pH of said aqueous phase is adjusted to a value between 0 and 14.
Claim 93
Dependent Claim
18 words
The process of claim 79 wherein said catalyst is added to said dispersion after said dispersion is formed.
Claim 94
Dependent Claim
13 words
The process of claim 79 wherein said organic polyisocyanate is an aromatic diisocyanate.
Claim 95
Dependent Claim
24 words
The process of claim 90 wherein said aromatic diisocyanate comprises from about 2.0 percent to about 75.0 percent by weight of said water-immiscible phase.
Claim 96
Dependent Claim
20 words
The process of claim 90 wherein said aromatic diisocyanate is 80 percent 2,4- and 20 percent 2,6-isomer of tolylene diisocyanate.
Claim 97
Dependent Claim
13 words
The process of claim 79 wherein said water-immiscible material is water-immiscible organic material.
Claim 98
Dependent Claim
14 words
The process of claim 93 wherein said water-immiscible organic material is a thiocarbamate herbicide.
Claim 99
Dependent Claim
14 words
The process of claim 93 wherein said water-immiscible organic material is an organophosphorous insecticide.
Claim 100
Dependent Claim
15 words
The process of claim 93 wherein said water-immiscible organic material is an insect hormone mimic.
Claim 101
Dependent Claim
17 words
The process of claim 93 wherein said water-immiscible organic material comprises at least two water-immiscible organic materials.
Claim 102
Dependent Claim
18 words
The process of claim 97 wherein said water-immiscible organic material comprises a thiocarbamate herbicide and an antidote therefor.
Claim 103
Dependent Claim
152 words
A process for encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing, at room temperature, in an aqueous phase a solution comprising water and a surfactant; (b) adding to said aqueous phase, at room temperature, a water-immiscible phase comprising organic polyisocyanate, a water-immiscible material to be encapsulated, and a catalyst capable of increasing the rate of reaction of said organic polyisocyanate to form polyurea; (c) dispersing said water-immiscible phase in said aqueous phase to establish droplets of the water-immiscible phase in the aqueous phase; (d) maintaining the dispersion at room temperature; and (e) adding to the dispersion a protective colloid; whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 104
Dependent Claim
152 words
A process for encapsulating water-immiscible material within discrete capsules of polyurea without addition of a second reactant, whereby hydrolysis of an isocyanate monomer to form an amine takes place which in turn reacts with another isocyanate monomer to form polyurea, which comprises the steps: (a) providing, at room temperature, in an aqueous phase a solution comprising water and a surfactant; (b) adding to said aqueous phase, at room temperature, a water-immiscible phase comprising organic polyisocyanate, a water-immiscible material to be encapsulated, and a catalyst capable of increasing the rate of reaction of said organic polyisocyanate to form polyurea; (c) dispersing said water-immiscible phase in said aqueous phase to establish droplets of the water-immiscible phase in the aqueous phase; (d) maintaining the dispersion at room temperature; and (e) adding to the dispersion a protective colloid; whereupon said water-immiscible material is encapsulated within discrete polyurea capsular enclosures directly usable without further separation or purification.
Claim 105
Dependent Claim
65 words
The process of claim 99 wherein said catalyst is selected from a group consisting of (a) a basic organic tertiary amine catalyst in the amount of about 0.01 percent to about 10.0 percent by weight based on the organic phase and (b) an alkyl tin acetate catalyst in the amount of about 0.001 percent to about 1.0 percent by weight based on the organic phase.
Claim 106
Dependent Claim
26 words
A process according to claim 99 which further comprises the step of adjusting the pH of said aqueous phase to a value between 0 and 14.
Claim 107
Dependent Claim
25 words
The process of claim 99 wherein the dispersed water-immiscible phase comprises droplets having a particle size of between about 0.5 microns to about 4000 microns.
Claim 108
Dependent Claim
13 words
The process of claim 102 wherein said dispersion is maintained by mild agitation.
Claim 109
Dependent Claim
27 words
The process of claim 104 wherein said catalyst is selected from the group consisting of a basic organic tertiary amine catalyst and an alkyl tin acetate catalyst.
Claim 110
Dependent Claim
69 words
The process of claim 104 wherein said water immiscible phase contains a catalyst selected from the group consisting of (a) a basic organic tertiary amine catalyst in the amount of about 0.01 percent to about 10.0 percent by weight based on the organic phase and (b) an alkyl tin acetate catalyst in the amount of about 0.001 percent to about 1.0 percent by weight based on the organic phase.
Claim 111
Dependent Claim
26 words
The process of claim 99 in which said water-immiscible material is water-immiscible organic material, whereupon said water-immiscible organic material is encapsulated within a polyurea capsular enclosure.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-08-24 | 1985-02-23 | 1985-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-24 | 1989-02-23 | 1989-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-24 | 1993-02-23 | 1993-08-25 | $7700.00 | Window Closed / Lapsed |