Encapsulating Normally Liquid Material Patents (Class 264/4)
  • Patent number: 4357269
    Abstract: A molding compound is disclosed comprising a diallyl phthalate compound and capsules of water.
    Type: Grant
    Filed: March 9, 1981
    Date of Patent: November 2, 1982
    Assignee: Rogers Corporation
    Inventors: Vincent R. Landi, Jeffrey L. Dalton
  • Patent number: 4356108
    Abstract: A process for the preparation of oil-containing microcapsules by interfacial condensation of a polyfunctional amine with a polyfunctional wall-forming material is disclosed. Microcapsules produced by this process have utility in the manufacture of carbonless copy paper. The process comprises emulsifying a mixture of a hydrophobic phase, which includes an oil, a chromogenic material and an oil soluble polyfunctional wall-forming material, and a hydrophilic phase, which includes water, a water soluble emulsifying agent and a water soluble salt of the desired polyfunctional amine. The amine salt may be formed in situ in the hydrophilic phase before the emulsification step.
    Type: Grant
    Filed: December 20, 1979
    Date of Patent: October 26, 1982
    Assignee: The Mead Corporation
    Inventors: Gerhart Schwab, Gerald T. Davis
  • Patent number: 4353962
    Abstract: A method and composition for the in-flight encapsulation of particles such as insecticides, herbicides, molluscicides, acaricides, fungicides, nutrients, pheromones, odorants, fragrances, attractants, repellents, trace elements, plant regulants, and the like is disclosed. The composition comprises, by weight, from 1 to 40 percent of said particles, from 0.1 to 25 percent of a film-forming polymer and from 35 to 99 percent of a liquid which renders said polymers soluble or dispersible. Often, other compounds may be added to impart desirable properties such as other film-forming polymers, crosslinking agent film modifying agents, core agents, and adhesives to improve adhesion to a target. The particle may be in a true solution, suspended, or emulsified through the action of surfactants and/or emulsifying agents. The film-forming polymers include various acrylic polymers and interpolymers of alpha-beta olefinically unsaturated carboxylic acids and N-methylol acrylic amides, as set forth in U.S. Pat. No.
    Type: Grant
    Filed: May 18, 1981
    Date of Patent: October 12, 1982
    Assignee: Environmental Chemicals, Inc.
    Inventors: Chester M. Himel, Nathan F. Cardarelli
  • Patent number: 4352883
    Abstract: A core material such as living tissue, individual cells, hormones, enzymes or antibodies is encapsulated in a semipermeable membrane that is permeable to small molecules for contact with the core material but is impermeable to potentially deleterious large molecules. Encapsulation may be carried out by suspending the core material in an aqueous medium containing a water soluble gum that can be reversibly gelled, forming the suspension into droplets, contacting the droplets with a solution of multivalent cations to gel the droplets as discrete, shape-retaining, water insoluble temporary capsules and cross-linking a surface layer of the temporary capsules to produce a semipermeable membrane around the capsules. Optionally the gel within the membrane may be reliquified by removing multivalent cations from the gel.
    Type: Grant
    Filed: March 28, 1979
    Date of Patent: October 5, 1982
    Assignee: Damon Corporation
    Inventor: Franklin Lim
  • Patent number: 4349456
    Abstract: Shaped and fired, porous or impermeable nonvitreous ceramic microcapsules of metal oxide, preferably transparent and polycrystalline, are made by a non-melt process comprising the liquid-liquid extraction of aqueous metal oxide precursor with a dehydrating liquid having a limited water solubility, and drying and firing the resulting gelled microcapsules. For example, an aqueous titania sol is added to an agitated body of n-butanol to form a dispersion of droplets of said sol and water is rapidly extracted from the droplets to form gelled microcapsules; the latter are recovered by filtration, dried, and fired to convert them into transparent, sealed or heat-sealable, non-vitreous ceramic, spherical microcapsules of polycrystalline titania. The microcapsules can be used as fillers for plastic and other composites or filled with a selected solid, liquid or gas for purpose of storing, transporting, or facilitating the use of the same.
    Type: Grant
    Filed: August 27, 1979
    Date of Patent: September 14, 1982
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Harold G. Sowman
  • Patent number: 4324683
    Abstract: A two step interfacial polymerization process for encapsulating operative chemically active substances in high quality semipermeable membranes. An emulsion is formed wherein the discontinuous phase contains the substance to be encapsulated and a first monomer. When a second monomer is added to the continuous phase, an imperfect membrane forms about the droplets of the discontinuous phase. Removal of the continuous phase, followed by resuspension of the raw microcapsules and addition of a second portion of second monomer, causes further polymerization strengthening the membranes and "patching" macroporous defects in them. The choice of solvents and control of reaction conditions such as pH, maximize the yield of operable labile substance encapsulated. A method of encapsulating a very high concentration of hemoglobin is also disclosed. Adaption of the two step process provides a method for forming and controlling the pore sizes in the membranes of a number of known prior art encapsulation processes.
    Type: Grant
    Filed: August 20, 1975
    Date of Patent: April 13, 1982
    Assignee: Damon Corporation
    Inventors: Franklin Lim, Richard D. Moss
  • Patent number: 4313930
    Abstract: Stable valepotriate compositions are produced by a process wherein impurities are removed from the pharmaceutically active extract of the valerianacea fruits, followed by a mixing with pharmaceutically acceptable sheathing materials and the formation of microspheres therefrom.
    Type: Grant
    Filed: October 31, 1979
    Date of Patent: February 2, 1982
    Assignee: Kali-Chemie Pharma GmbH
    Inventors: Martin Wischniewski, Lutz Feicho, Werner Althaus
  • Patent number: 4307169
    Abstract: Electroscopic marking particles comprising microcapsules consisting of a pressure fixable core and pressure rupturable shell which is characterized by the core comprising pressure fixable material and coloring matter and the shell is formed by interfacial polycondensation.
    Type: Grant
    Filed: March 10, 1980
    Date of Patent: December 22, 1981
    Assignee: Moore Business Forms, Inc.
    Inventor: Josef Matkan
  • Patent number: 4294921
    Abstract: A method of hardening gelatin which uses both a gelatin hardener and a polymer having a repeating unit of the formula (I): ##STR1## wherein R represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a halogen atom; M represents a hydrogen atom, an alkali metal atom, an alkali earth metal atom, or an organic base; X represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group, an alkylamino group, or a halogen atom; m represents 0, 1 or 2; and n represents 1 or 2.
    Type: Grant
    Filed: June 23, 1980
    Date of Patent: October 13, 1981
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Jun Yamaguchi, Takashi Naoi, Hidefumi Sera, Kunio Ishigaki, Masasi Ogawa
  • Patent number: 4293677
    Abstract: One package compositions of organopolysiloxane containing alkenyl radicals, organohydrogenpolysiloxane and a catalyst for the addition reaction can be prepared by using microcapsules which contain the organohydrogenpolysiloxane. The microcapsules have nonpermeable films which keep the organohydrogenpolysiloxane separated from the other reactive components. When the microcapsules are ruptured, the composition cures. These one-package compositions can be used as coating materials, potting materials for electrical equipment, release coatings and bonding agents.
    Type: Grant
    Filed: June 9, 1980
    Date of Patent: October 6, 1981
    Assignee: Toray Silicone Company, Ltd.
    Inventor: Takeshi Imai
  • Patent number: 4285720
    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.
    Type: Grant
    Filed: July 7, 1978
    Date of Patent: August 25, 1981
    Assignee: Stauffer Chemical Company
    Inventor: Herbert B. Scher
  • Patent number: 4286020
    Abstract: A method and composition for the in-flight encapsulation of particles such as insecticides, herbicides, molluscicides, acaricides, fungicides, nutrients, pheromenes, odorants, fragrances, attractants, repellants, trace elements, and the like. The composition comprises, by weight, from 1 to 40 percent of said particles, from 0.3 to 25 percent of a film-forming polymer and from 35 to 99 percent of a solvent which renders said polymers soluble. Often, other compounds may be added to impart desirable properties such as a second film-forming polymer, crosslinking agents, film modifying agents, and adhesives to improve adhesion to a target. The particle may be in a true solution suspended or emulsified through the action of surfactants and/or emulsifying agents. The film-forming polymer is selected from the class consisting of polyvinyl ethers, polyvinyl acetate, and interpolymers of alpha-beta olefinically unsaturated carboxylic acids and N-methylol acrylic amides, as set forth in U.S. Pat. No. 3,007,887.
    Type: Grant
    Filed: May 15, 1980
    Date of Patent: August 25, 1981
    Assignee: Environmental Chemicals, Inc.
    Inventors: Chester M. Himel, Nathan F. Cardarelli
  • Patent number: 4251387
    Abstract: Techniques for producing semipermeable microcapsules by interfacial polymerization are disclosed. The material to be encapsulated and a hydrophilic monomer are emulsified within a hydrophobic continuous phase. Polymerization is initiated by dissolving a second monomer in the continuous phase, and occurs only at the interface of the emulsion to result in the formation of macroporous, poorly defined capsule membranes. Next, the affinity of the continuous phase for the hydrophilic monomer is varied by altering the polarity of the continuous phase. This step is accomplished either by isolating and resuspending the raw capsules in a fresh continuous phase of different polar character, or by mixing a second solvent with the continuous phase. By controlling the affinity and the concentration of the second monomer, it is possible to produce microcapsules having uniform capsule membranes and a selected upper limit of permeability.
    Type: Grant
    Filed: April 17, 1979
    Date of Patent: February 17, 1981
    Assignee: Damon Corporation
    Inventors: Franklin Lim, Richard D. Moss
  • Patent number: 4218409
    Abstract: Method is disclosed for forming encapsulated material. Centrifugal force developed by a rotating nozzle having a plurality of radial orifices is used for extruding material to be encapsulated. The nozzle is mounted for rotation about a generally vertical axis and is provided with a circumferential outside surface near its bottom inclined upwardly away from the axis of the nozzle which, when partially submerged in a liquid during rotation, impels a sheet or spray of the liquid along the circumferential surface and shears off successive leading tips of extruded material to form capsules.
    Type: Grant
    Filed: August 16, 1978
    Date of Patent: August 19, 1980
    Assignee: Eastman Kodak Company
    Inventor: Clarence C. Dannelly
  • Patent number: 4211668
    Abstract: This invention relates to a process for making microscopic size capsules from an emulsion having an inner oily or hydrophobic phase (material to be encapsulated) and an outer hardenable hydrophilic phase. The process is characterized by the step of contacting said emulsion with a break-up fluid capable of dividing said emulsion into substantially separate capsules having an inner hydrophobic phase and an outer hardenable hydrophilic phase; and then hardening the hydrophilic phase of said capsules to form microscopic size capsules or microencapsulations.The separated capsules can contain clusters of capsules, or they may be made as separate, individual capsules. In the preferred embodiment, the break-up fluid contains a surfactant capable of enhancing the break-up function of the fluid so that the separated capsules are predominately individual capsules.This invention also relates to microscopic size capsules formed by this process.
    Type: Grant
    Filed: April 24, 1978
    Date of Patent: July 8, 1980
    Assignee: Thalatta, Inc.
    Inventor: Clarence R. Tate
  • Patent number: 4187194
    Abstract: A process for forming capsules comprising:(i) forming a solution of wall material and core material in a solvent;(ii) admixing said solution with an immiscible liquid to form a dispersion wherein said solution is the dispersed phase and the immiscible liquid is the continuous phase;(iii) altering the solubility characteristics of the solvent for said solution to effect sequential phase separation of said core and wall materials, respectively, thereby forming capsules of core material encapsulated with wall material; and(iv) recovering said capsules.
    Type: Grant
    Filed: February 7, 1974
    Date of Patent: February 5, 1980
    Assignee: Xerox Corporation
    Inventors: Russel E. Wellman, Robert W. Brown
  • Patent number: 4145517
    Abstract: Linear copolyesters are contemplated having the following repeating units: ##STR1## in their backbone structure. These polyesters have utility in the packaging industry for packaging various comestibles.
    Type: Grant
    Filed: November 2, 1977
    Date of Patent: March 20, 1979
    Assignee: Owens-Illinois, Inc.
    Inventor: Santos W. Go
  • Patent number: 4143103
    Abstract: A method of making a display characterized by a plurality of particles which have an electrical anisotropy due to hemispherical surface coatings of different Zeta potential and their distribution in a volume of a dielectric liquid and which also have an optical anisotropy due to the hemispherical surface coatings having different optical characteristics. The particles are mixed with a light transparent liquid which is subsequently cured to form an elastomeric or rigid slab. Following curing of the liquid, the slab is emersed in a plasticizer (dielectric liquid) which is absorbed by the slab and which causes the slab to expand slightly. Expansion of the slab around the particles provides a plasticizer-filled cavity around each particle which cavities allow the particles to rotate to provide a display in accordance with their optical anisotropy but does not allow substantial translation of the particles.
    Type: Grant
    Filed: May 4, 1976
    Date of Patent: March 6, 1979
    Assignee: Xerox Corporation
    Inventor: Nicholas K. Sheridon
  • Patent number: 4123206
    Abstract: Apparatus and method are disclosed for forming encapsulated material. Centrifugal force developed by a rotating nozzle having a plurality of radial orifices is used for extruding material to be encapsulated. The nozzle is mounted for rotation about a generally vertical axis and is provided with a circumferential outside surface near its bottom inclined upwardly away from the axis of the nozzle which, when partially submerged in a liquid during rotation, impels a sheet or spray of the liquid along the circumferential surface and shears off successive leading tips of extruded material to form capsules.
    Type: Grant
    Filed: February 7, 1977
    Date of Patent: October 31, 1978
    Assignee: Eastman Kodak Company
    Inventor: Clarence C. Dannelly
  • Patent number: 4112631
    Abstract: A capsule containing fine abrasive grains dispersed in a liquid or low melting solid grinding aid can be substituted for conventional abrasive polishing grains. A novel coated abrasive structure is made by bonding such capsules to a backing sheet.
    Type: Grant
    Filed: May 29, 1973
    Date of Patent: September 12, 1978
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Robert N. Howard
  • Patent number: 4110491
    Abstract: Method and apparatus for encapsulating and coagulating an elastomeric latex wherein the latex is introduced as drops into an encapsulating-coagulating liquid via a draft tube through which the encapsulating-coagulating liquid is impelled downwardly in generally linear flow, and thereafter recycling the encapsulating-coagulating liquid into the top of the draft tube free of particulate elastomeric product.
    Type: Grant
    Filed: June 29, 1976
    Date of Patent: August 29, 1978
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Robert M. Secor
  • Patent number: 4107071
    Abstract: Microcapsules having a capsule core material surrounded by a relatively impermeable, densified protective wall and a method of producing such microcapsules are disclosed. To produce the microcapsules, an agitated system is provided including a liquid vehicle as a major component of the system and constituting a continuous first phase of the system. A plurality of discrete capsule core material entities are dispersed in the liquid vehicle and constitute a discontinuous second phase. A film-forming, cross-linkable, polymeric base material is also present in the liquid vehicle and, upon induction of phase separation within the agitated system, forms a sheath about the capsule core material entities. The formed sheath also contains entrapped liquid vehicle; however, a major portion of the entrapped liquid vehicle is subsequently extracted from the sheath, and the resulting densified polymeric base material in the sheath is then cross-linked to form a densified protective wall around the capsule core material.
    Type: Grant
    Filed: February 16, 1977
    Date of Patent: August 15, 1978
    Assignee: Capsulated Systems, Inc.
    Inventor: Robert G. Bayless
  • Patent number: 4089834
    Abstract: Microcapsules having controlled structural integrity are produced by a process which involves admixing a thermosetting condensation polymer-containing oily solution and a polymer-containing aqueous solution and causing a chemical reaction between the polymers at the resulting oil/water interface. The so-formed microcapsules have excellent water resistance and may be employed in the formation of opacifying agents in coatings and particularly in paint films.
    Type: Grant
    Filed: January 11, 1973
    Date of Patent: May 16, 1978
    Assignee: Champion International Corporation
    Inventor: Mabrin P. Powell
  • Patent number: 4087369
    Abstract: Granular peroxybleach activated detergent compositions are disclosed containing a crystalline activator component having a well-defined particle diameter and a narrowly defined rate of hydrolysis. These compositions have improved stability, particularly with respect to the activator, under prolonged, particularly alkaline, storge conditions. Peroxybleach activator agglomerates having a specific particle diameter and detergent compositions containing these agglomerates are also disclosed. The agglomerating agent is defined through its inertness versus the activator and also in its melting point. The bleach-activator detergent compositions of this invention are stable under prolonged (alkaline) storage thereby remaining substantially unchanged with respect to the appearance and performance characteristics of the freshly prepared detergent composition.
    Type: Grant
    Filed: November 8, 1976
    Date of Patent: May 2, 1978
    Assignee: The Procter & Gamble Company
    Inventor: Jean Wevers
  • Patent number: 4076774
    Abstract: In accordance with a preferred embodiment of this invention, an active agent, such as a catalyst or a cocatalyst, is encapsulated in a dual-walled microcapsule. Both walls of the microcapsule are polymerization reaction products and both are formed in one basic process. The active agent is initially dissolved in a slowly polymerizing liquid monomer mixture such as a solution of toluene diisocyanate and a polyoxyalkylene polyol. The "monomer solvent" and the active agent combination is selected so that the active agent is nonreactive but soluble in the liquid monomer and insoluble in the polymer formed therefrom. However, before the active agent precipitates, the solution is dispersed in a nonreactive medium and the outer polymeric wall is formed by vigorously stirring the dispersion and then adding a reactive polyfunctional monomer.
    Type: Grant
    Filed: February 27, 1976
    Date of Patent: February 28, 1978
    Assignee: General Motors Corporation
    Inventor: William T. Short
  • Patent number: 4073833
    Abstract: An improved process for releasably enclosing a solution of a micelle-forming surfactant in a receptacle comprising a microporous cellulose membrane is provided.
    Type: Grant
    Filed: December 8, 1975
    Date of Patent: February 14, 1978
    Assignee: The Procter & Gamble Company
    Inventor: Robert G. Laughlin
  • Patent number: 4016099
    Abstract: A method is provided for forming encapsulated particles comprising forming a dispersion of core material in a solution of wall material in a solvent; drowning said dispersion in at least one liquid which is miscible with the solvent and in which at least the wall material is substantially insoluble, to effect phase-separation of said wall material, whereby said wall material deposits about said core material forming a dilute dispersion of particles comprising said core material encapsulated with said wall material in said liquid, and recovering said encapsulated particles from said liquid.
    Type: Grant
    Filed: March 27, 1972
    Date of Patent: April 5, 1977
    Assignee: Xerox Corporation
    Inventors: Russel E. Wellman, Robert W. Brown
  • Patent number: 4010038
    Abstract: In a process for producing microcapsules of complex hydrophilic colloid material enclosing fine particles of a hydrophobic substance, the improvement characterized in that:An acid-treated gelatin and at least one of carboxy-modified cellulose derivatives are used as the hydrophilic colloid materials, the amount of the cellulose derivative being 1/7 to 1/40 the amount of the gelatin by weight, the cellulose derivative having an average polymerization degree of 50 to 1,000 and a carboxyl substitution degree of 0.4 to 1.5, andThe coacervation of the colloid material solution is effected at a pH of 4.8 to 6.0.
    Type: Grant
    Filed: April 1, 1975
    Date of Patent: March 1, 1977
    Assignee: Kanzaki Paper Manufacturing Co., Ltd.
    Inventors: Hiroshi Iwasaki, Shunsuke Shioi, Jujiro Kouno
  • Patent number: 3994827
    Abstract: The micro-capsules are formed by providing the coating of capsulating agents comprising acetate sulfate of polyglycosides on the core substances. Aqueous solutions of the salt of cellulose acetate sulfate, starch acetate sulfate or dextran acetate sulfate are used as the said acetate sulfate of polyglycosides and the oily substances such as alkyl biphenyl, liquid paraffin, fat and higher alcohol, and pulverulent substances such as active carbon and yeast are used as the core substances. According to the method of present invention, the core substances are added to aqueous solutions of the said polyglycosides to be emulsified and dispersed therein, and then aqueous solutions of polycations are added there to cause insoluble complex comprising the said polyglycosides and polycations, and as resulting the core substances are coated by insoluble complex.
    Type: Grant
    Filed: December 17, 1974
    Date of Patent: November 30, 1976
    Assignee: Jujo Paper Co., Ltd.
    Inventors: Tomoo Sakai, Tsuguo Kagaya, Kingo Yokota, Kunio Hata
  • Patent number: 3993831
    Abstract: Microcapsules containing oily droplets are produced in the absence of coacervation by admixing a partially condensed, formaldehyde condensation product in an aqueous medium and an oil-in-water emulsion, which emulsion comprises water-immiscible oily material as the disperse phase and an aqueous colloidal solution of an amphiphilic emulsifying agent as the dispersion medium. This single admixing effects the separation of the resin from the aqueous medium and precipitation thereof in solid particle form about a nucleus of the oily material, and the resulting microcapsules have a high degree of structural integrity.
    Type: Grant
    Filed: April 8, 1971
    Date of Patent: November 23, 1976
    Assignee: Champion International Corporation
    Inventor: Anthony E. Vassiliades
  • Patent number: 3985840
    Abstract: Microporosity is introduced into a membrane capable of retaining a liquid by (a) forming a single homogeneous liquid phase comprising a first material and a second material, at a temperature above the melting points of said materials, said first material being incompatible with said second material when said liquid phase is cooled to room temperature, the volume contraction ratio being at least about 1.2, and (b) permitting the liquid phase to cool to room temperature, whereby said first material separates out as a dispersed solid phase and creates micropores which extend completely through said membrane.
    Type: Grant
    Filed: December 20, 1973
    Date of Patent: October 12, 1976
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: David A. Hofacker
  • Patent number: 3977992
    Abstract: The disclosed substantially spherical capsules are particularly adapted for containing a liquid and have permeable or semi-permeable capsule walls. The capsule walls can comprise a first crystalline phase, an amorphous phase which ordinarily is intimately associated with the crystalline phase, and, preferably, a dispersed (discontinuous) second crystalline or semi-crystalline phase such as a wax. These capsules have the ability to release a solute by an effect resembling osmosis and to release a liquid by a transmission and evaporation mechanism.
    Type: Grant
    Filed: November 8, 1971
    Date of Patent: August 31, 1976
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: David A. Hofacker
  • Patent number: 3970585
    Abstract: In a process for preparing oil-containing microcapsules comprising cooling a coacervate dispersion of a gelatin-containing colloid deposited around individual oil droplets to cause gelation of the colloid and subsequently hardening the gelled colloid by adding to the dispersion a hardening agent and adjusting the pH to the alkaline region, the improvement which comprises adding to the dispersion, after gelation but prior to hardening, an aqueous solution of an anionic high molecular weight electrolyte and an aqueous solution of an anionic surface active agent. Specific electrolytes and specific surface active agents are disclosed.
    Type: Grant
    Filed: April 24, 1973
    Date of Patent: July 20, 1976
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroharu Matsukawa, Shizuo Katayama, Masataka Kiritani
  • Patent number: 3965033
    Abstract: In a process for producing oil-containing microcapsules by coacervation comprisingA. introducing a fine powder or hydrophobic liquid into a high molecular weight electrolytic wall-forming colloid;B. coacervating the resulting dispersion or emulsion;C. cooling the resulting coacervate to gel it and form the wall of said microcapsules; andD. hardening said wall of said microcapsules; the improvement which comprises adding a phenolic compound to the system.
    Type: Grant
    Filed: January 31, 1974
    Date of Patent: June 22, 1976
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroharu Matsukawa, Keiso Saeki
  • Patent number: 3964294
    Abstract: Microencapsulated spheroids containing a coded, volatile electron absorbing substance are dispersed into a material to be regulated such as crude oil in a tanker. Samples of the material such as an oil spill are collected and the source of the material is determined by electron capture gas chromatographic detection of the electron absorbing substance.
    Type: Grant
    Filed: November 1, 1974
    Date of Patent: June 22, 1976
    Assignee: California Institute of Technology
    Inventors: Frederick H. Shair, Peter G. Simmonds, Robert B. Leighton, Peter J. Drivas
  • Patent number: 3962383
    Abstract: This invention relates to a method and apparatus for manufacturing seamless material-filled capsules characterized by the fact that a capsule filler material, a sol solution and a water-insoluble solution in the form of a continuous jet are fed from a triple orifice of the same core into a stream of hardening solution, the spherical drops consisting of the above mentioned three layers are completed due to their interfacial surface tensions, then said water-soluble solution of said outermost layer is caused to strike several interrupting plates to have said water insoluble layer destroyed and separated from the sol solution as a second layer to react said sol solution with said hardening solution at this instant for forming a water-insoluble film and the diameter the wall thickness of said spherical drop can be changed easily by modifying the flow speed of the hardening solution and the diameter of said orifice.
    Type: Grant
    Filed: April 9, 1973
    Date of Patent: June 8, 1976
    Inventors: Yoshiro Hagiwara, Toshiyuki Suzuki, Akira Imai
  • Patent number: 3959457
    Abstract: In a finely dispersed emulsion of a water immiscible solution of an organic polyfunctional Lewis base and an aqueous solution of a partially hydrophilic, partially lipophilic polyfunctional Lewis acid, a reaction occurs at the phase interface to produce a novel microparticulate material comprised of the reaction product of the Lewis acid and the Lewis base. The maximum particle size dimensions of the microparticulate material depends on the degree of dispersion in the emulsified reaction mixture and may be as low as 2 microns or smaller.
    Type: Grant
    Filed: February 8, 1973
    Date of Patent: May 25, 1976
    Assignee: Temple University
    Inventors: Tully J. Speaker, Lawrence J. Lesko
  • Patent number: 3948845
    Abstract: Opalescent-appearing compositions are prepared by dispersing conjugated diene/vinyl aromatic compound copolymers in a suitable solvent. Encapsulated compositions of this invention display the colors and brilliance of precious opal.
    Type: Grant
    Filed: October 17, 1974
    Date of Patent: April 6, 1976
    Assignee: Phillips Petroleum Company
    Inventors: John W. Marx, James N. Short
  • Patent number: 3944502
    Abstract: In a process for producing microcapsules containing hydrophobic oil drops by complex coacervation including a conventional prehardening treatment in which an aldehyde and an alkali material are added to the system, the improvement which comprises adding gelatin having an isoelectric point lower than that of the gelatin employed for forming the walls of the coacervates to the system at a temperature lower than the gelling point of the gelatin employed for forming the walls of the coacervates, but prior to the simultaneous presence in the system of said aldehyde and alkali material, in an amount sufficient to prevent an increase in viscosity due to the reaction of gelatin and aldehyde during said prehardening step.
    Type: Grant
    Filed: October 15, 1973
    Date of Patent: March 16, 1976
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroharu Matsukawa, Keiso Saeki, Takeo Shimada
  • Patent number: 3943063
    Abstract: Microcapsules are made by (a.) dispersing or dissolving a core substance in a film-forming polymer solution, (b.) emulsifying in fine droplets the resulting dispersion or solution in a vehicle which is poorly miscible with the solvent of the polymer solution and which doesn't dissolve said polymer to prepare an emulsion, and (c.) adding to the emulsion a non-solvent for the polymer wherein the non-solvent is miscible with the solvent, poorly miscible with the vehicle, and does not dissolve the polymer, whereby the solvent is removed by being absorbed by non-solvent emulsion droplets to precipitate the polymer film around the core substance.
    Type: Grant
    Filed: January 2, 1973
    Date of Patent: March 9, 1976
    Assignee: Toyo Jozo Company, Ltd.
    Inventors: Masataka Morishita, Yoshihito Inaba, Mitsuru Fukushima, Sadami Kobari, Akiho Nagata, Jinnosuke Abe
  • Patent number: RE28779
    Abstract: Method of producing microcapsules containing hydrophobic oily liquid, which comprises, in producing microcapsules by complex coacervation, using gelatin, as at least one hydrophilic colloid, adding an aqueous solution of shock preventing agent at a temperature lower than the gelling point of gelatin in order to prevent a rise in viscosity due to reaction of gelatin and aldehyde during hardening pretreatment and rapidly accomplishing hardening pretreatment.
    Type: Grant
    Filed: August 30, 1973
    Date of Patent: April 20, 1976
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shizuo Katayama, Hiroharu Matsukawa, Junichi Matsuyama, Masaya Yamamoto