Abstract: Disclosed are a plurality of particles having a narrow particle size distribution, a processes for forming the same, and films containing the same. The plurality of particles, includes one or more discrete polymer shells, wherein at least one of the polymer shells is crosslinked with at least one monomer containing two or more double bonds polymerizable by free radical means; and a core material encased in the polymer shells, wherein the plurality of particles have a polydispersity of from 1.3 to 1.0.

Abstract: The present invention relates to a process of obtaining microcapsules, comprising mainly the following stages: preparing a scarcely water-soluble organic phase containing a determined amount of acid chlorides, forming an emulsion of said organic phase in an aqueous phase, adding to the aqueous emulsion an amount of at least one polyoxyalkylene polyamine, reacting the monomers containing the amine and acid chloride functions so as to form a polyamide membrane around the emulsified organic phase, recovering the microcapsules obtained. The present invention also relates to a microcapsule.

Abstract: The invention relates to a process for preparing microcapsules by coacervation, wherein the cross-linking of a protein is carried out by a plant extract rich in substituted or unsubstituted phenolic compounds.

Abstract: A process for encapsulation of polar organic solvents with amphiphilic copolymer shell using controlled/living polymerization is provided for the first time. To encapsulate polar core-oils an amphiphilic polymer is required that has low interfacial tensions with both the oil phase and the water phase. For example, Poly(methyl methacrylate-co-poly(ethylene glycol) methacrylate) (PMMA-co-PegMA) was prepared in suspension polymerization conditions using atom transfer radical polymerization (ATRP). ATRP ensures that the water soluble comonomer, PegMA, is incorporated into every polymer chain throughout the polymerization reaction so that all chains possess the desired amphiphilic character. Crosslinking of PMMA-co-PegMA with diethylene glycol dimethacrylate (DegDMA) yielded hollow capsular particles at 31 mol % PegMA in the terpolymer.

Abstract: A composition for fabricating phase-change-material microcapsule and a method for fabricating microcapsule are provided. The composition at least includes 5% to 40% weight percentage of waterborne polyurethane aqueous solution, phase change material, monomer and solid wax. The lipophilic monomer solves in the phase change material and the weight percentage is between about 3% and 12% and the weight ratio of lipophilic monomer to waterborne polyurethane is between about 25% and 50%. The composition is emulsified by stirring and several stages heating process is performed to fabricate the microcapsules.

Abstract: The invention relates to a multi-stage method for producing gas-filled microcapsules. In one stage of the method, the substance that forms the coat is polymerized. The microcapsules are formed in a physically and/or temporally separate stage, by means of a structuring process. The polymerization is carried out with moderate stirring, while the microcapsules are structured in dispersing conditions.

Abstract: Compositions for sustained delivery of a biomolecule including an anionic polymer and a cationic polymer which ironically interact with each other and, optionally, with the biomolecule. Methods for making the compositions, including the step of combining the negatively charged polymer with the positively charged polymer to form an ionic complex are also provided. The biomolecule may be complexed with one of the polymers before it is complexed with the oppositely charged polymer. The complex is exposed to conditions that cause the formation of precipitated microcarriers, such as a change in pH or the addition of a complexing molecule. The compositions are preferably formulated into microcarriers.

Abstract: A method of forming, by polymerization in an aqueous dispersion at pressures in excess of one atmosphere, a plurality of porous particles having at least one polymeric phase and, additionally, having a pore filling phase containing a fugitive substance is disclosed. Replacement of the fugitive substance with a gas is further disclosed. Gas-filled porous particles and their aqueous dispersions are also disclosed.

Abstract: A process of micro-encapsulating a volatile liquid includes selecting a volatile liquid, such as Isophorone, and porous ceramic particles for encapsulating the volatile liquid. The volatile liquid and porous particles are mixed and a vacuum is applied to the mixture to impregnate the volatile liquid in the porous particles. A polymer catalyst for the polymer resin, such as an epoxy catalyst for use with an epoxy resin, is mixed with the volatile liquid and porous particles to saturate the particles. The polymer resin, such as epoxy resin, is added to the mixture for forming a resin cured shell around the porous particle holding the volatile liquid to form a microencapsulated volatile liquid. The resin is only cured on the outer shell of the porous particle when coming in contact with the catalyst supported with the volatile liquid in the porous particle.

Abstract: A novel adhesive formed in situ in a microcapsule and method for forming such a pressure sensitive or flowable adhesive in situ in a microcapsule is disclosed. The method for forming the novel adhesive comprises providing an aqueous mixture of wall material in water; adding a substantially water insoluble core material, free radical initiator, and a solvent for the pre-polymers to the aqueous mixture. The core material comprises a first addition polymerizable pre-polymer having a Tg of less than about 0° C., a flash point of at least 75° C., and a boiling point of at least 175° C. These are typically selected from acrylate or methacrylate type materials. Optionally included is a second addition polymerizable pre-polymer for providing cross-linking or interaction between polymer chains. High shear agitation is provided to the aqueous mixture to achieve a particle size of about 0.1 to 250 microns.

Abstract: The invention relates to microcapsules for which the walls comprise reaction products of polyisocyanates with guanidine compounds and amines.

Abstract: The present invention relates to water-insoluble solid particles, especially pigments, which characteristically are coated with at least one layer of at least one product resulting from the reaction between at least one molecule capable of becoming hydrated in contact with water and at least one lipophilic molecule. It further relates to cosmetic, pharmaceutical and agricultural compositions comprising such particles and to the manufacture and use of said particles.

Abstract: Microcapsules formed from an aminoplast shell wall and an encapsulated ingredient or ingredients enclosed within the wall in which the wall contains a base-cleavable ester moiety. These capsules have been found to be sensitive to the presence of base such that in the presence of base, the capsule walls are relatively quickly disintegrated or degraded so as to produce a relatively quick release of the encapsulated materials. Microcapsules of this invention are particularly suitable for use in controlling insects having an alkaline gut such as certain lepidoptera in that the capsule shell wall may be designed so as to quickly disintegrate under the alkaline conditions present in the gut of the insect thus providing a microcapsule which is safe to handle but which is selectively effective against certain undesirable insects while not harmful to beneficial insects or insects which do not feed on the capsule materials.

Abstract: Dual shell microcapsule aggregate particles and copy materials coated therewith, such aggregate particles having inner shells surrounding chromogenic nucleus material, and outer shells encompassing multiple such inner shells to form aggregate particles thereof. The inner shells are derived from polar pre-polymer compositions. The outer shells are derived from complex colloids such as gelatin and gelatin derivatives. The outer shell material causes agglomeration of the inner shells into aggregate particles, thus increasing the sizes of the particles without increasing the sizes of the respective inner-shell microcapsules which contain the chromogenic material.

Abstract: The invention relates to a process for the preparation of dispersible colloidal systems in the form of nanocapsules whose wall consists of a polymer obtained by the polycondensation of two monomers, &agr; and &bgr;, and whose core consists of a substance B, characterized in that:

Abstract: The invention concerns a method for preparing mineral capsules consisting of aqueous liquid core enclosed in mineral coating, said method consisting in: 1) emulsifying an aqueous fluid in a phase non-miscible with said aqueous fluid so as to disperse it therein in the form of droplets; 2) contacting, in the resulting emulsion, at least a zirconium, silicon, aluminium and/or a transition metal capable of being hydrolysed or subjected to condensation polymerisation in temperature and pH conditions suitable for forming a precipitate consisting of the corresponding oxide or hydroxide; 3) recuperating the resulting mineral capsules and, if required, purifying them.

Abstract: Crosslinked fine particles having a Tg of 100° C. or higher and an amount of remaining double bonds of 0.01 mmol/g or more, which are obtainable by polymerizing a compound (a1) having one or two radical-polymerizable ethylenic unsaturated groups in the molecule and a compound (a2) having three or more (meth)acryloyl groups in the molecule.

Abstract: A microcapsule having a mean diameter of from about 0.1 to about 5 mm, a membrane and a matrix containing at least one active principle wherein the microcapsule is the product of the process comprising the steps of (a) forming an aqueous matrix by heating an aqueous solution comprised of a gel former, a chitosan and active principle; (b) adding the aqueous matrix to an aqueous solution of an anionic polymer selected from the group consisting of a salt of alginic acid and an anionic chitosan derivative.

Abstract: The present invention provides novel encapsulation compositions and methods. In particular, the invention relates to fluorescent capsule compositions, which consists of a layer of a polymer shell enclosing one or more fluorescent materials such as fluorescent microspheres and which are capable of emitting at least two distinct fluorescent signals. Also provided are methods for their preparation. The compositions and methods of this invention are useful in a variety of applications, including preparation of multiplexed arrays for industrial, chemical, immunological, and genetic manipulation and analysis especially as related but not limited to flow cytometry.

Abstract: The present invention provides a polymerizable organosilicon nanocapsule, which includes:

Abstract: The invention relates to microcapsules for which the walls comprise reaction products of polyisocyanates, guanidine compounds, and optionally amines, wherein the polyisocyanates have an isocyanurate content of at least 30% by weight, based on polyisocyanate, and the walls comprise on average less than 9% by weight, based on the total weight of the microcapsule.

Abstract: A particle resistant to storage of at least one first and at least one second component, wherein

Abstract: A gyricon sheet including a binder with rotating elements and dielectric fluid therein, and further including a chemical absorbent in association therewith. The chemical absorbent, such as zeolite or charcoal, absorbs contaminants present in the gyricon sheet that interfere with the reliable operation of the display. The chemical absorbent may be present either in the gyricon sheet itself or in a separate scavenger layer adjacent to and in contact with the gyricon sheet. The presence of the chemical absorbent significantly increases the length of time that the display can reliably display images.

Abstract: A microencapsulated adhesive and a method for producing that microencapsulated adhesive is disclosed. The adhesive is produced from an alkyl acrylate or methacrylate monomer having about 4 to about 12 carbon atoms, or a mixture thereof. The monomer is encapsulated by interfacial polymerization, gelatin/gum arabic coacervation or melamine/formaldehyde encapsulation. The microcapsules may be polyamide or polyurea. The monomer is polymerized in the microcapsules by heating to form an adhesive that is non-tacky, but becomes tacky upon application of external forces, such as shearing. The microencapsulated adhesive composition may be used, among other applications, as an adhesive for stamps or envelopes.

Abstract: A composition and method of fabrication are presented with which nanoparticles may be used as a tool to deliver drugs to a specific target within or on a mammalian body Specifically, by using stabilizers other than Dextran 70.000 during the polymerization process, according to the present invention, surfactants, which were deemed necessary coating material in the prior art, are no longer required. This is a significant simplification of the fabrication procedure. Many substances are useful as stabilizers, but the preferred stabilizers comprise Dextran 12.000 or polysorbate 85. In the present invention a drug is either incorporated into or adsorbed onto the stabilized nanoparticles. This drug/nanoparticle complex is then administered to the organism on any route such as by oral application, injection or inhalation, whereupon the drug exerts its effect at the desired site of pharmacological action.

Abstract: Solid water-dispersible compositions containing microencapsulated pesticides are produced by spray-drying an aqueous suspension of said pesticides in the presence of a water-soluble polymer, preferably polyvinyl alcohol.

Abstract: Particles have a hydrophilic core, for instance including an enzyme and a polymer, surrounded by a shell formed by interfacial condensation polymerisation in the presence of a polymeric stabilizer. Preferably the polymeric stabilizer is a random copolymer which will concentrate at the interface between oil and water and association by ionic interaction, condensation or otherwise is achieved between the stabilizer and one of the reactants before reaction with the other reactant. Dispersions of aqueous capsules in an aqueous medium are also disclosed.

Abstract: Inorganic-organic hybrid mixture sol-gel encapsulated lipid vesicles which are composed of silyl lipids or a mixture of silyl lipids and phospholipids are provided. The present invention also provides encapsulated Langmuir Blogget (LB) membranes and biological macromolecules. The sol-gel encapsulated lipid vesicles, LB membranes and proteins possess a higher stability than conventional vesicles. Inorganic-organic hybrid mixture sol-gels are provided as novel sol-gel materials possessing desirable mechanical and physicochemical properties. Also provided are methods of preparing encapsulated lipid vesicles, LB membranes and proteins. Methods of performing renal dialysis using compositions of the invention are also provided.

Abstract: Microcapsules are prepared by polycondensation of a melamine/formaldehyde resin mixture in water, in which essentially water-insoluble material forming the capsule core is dispersed, in the presence of an anionic protective colloid, by a process wherein the melamine/formaldehyde resin mixture is composed of: a) an aqueous solution of a condensate of a1) 1 mol of melamine, a2) from 2 to 5 mol of formaldehyde and a3) from 0 to 0.5 mol of a melamine derivative which can undergo an addition or condensation reaction with formaldehyde and a4) from 1 to 5 mol of a C1-C3-alkanol and b) from 0.01 to 1 mol of a water-soluble primary, secondary or tertiary amine or ammonia.

Abstract: The present invention relates to a process for the preparation of microencapsulated polymers having a high surface smoothness, a soluble fraction of less than 6%, and a swelling index of between 1.3 and 9 by polymerizing a microencapsulated monomer mixture suspended in an aqueous phase containing at least one hydroxyaromatic compound as polymerization inhibitor, wherein the microencapsulated monomer mixture contains (a) 34 to 99.7% by weight of a monomer having one polymerizable C═C double bond, (b) 0.1 to 15% by weight of a crosslinking agent having at least 2 polymerizable C═C double bonds, (c) 0.2 to 1.0% by weight of at least one aliphatic peroxyester as polymerization initiator, and (d) 0 to 50% by weight of additives, the percentages being based on the sum of the components (a) to (c).

Abstract: In the preparation of microcapsules having shell walls of organopolysiloxane and a core material, the shell walls are produced in situ by hydrolysis and polycondensation of organosilanes and/or their condensates having not more than 4 silicon atoms.

Abstract: A process for encapsulating a partially water-miscible organic material within a polyurea or polyurethane shell is provided utilizing a water-soluble tertiary amine in the reaction dispersion. Microcapsules and methods of using microcapsules are also provided.

Abstract: Particles have a hydrophilic core, for instance including an enzyme and a polymer, surrounded by a shell formed by interfacial condensation polymerisation in the presence of a polymeric stabiliser. Preferably the polymeric stabiliser is a random copolymer which will concentrate at the interface between oil and water and association by ionic interaction, condensation or otherwise is achieved between the stabiliser and one of the reactants before reaction with the other reactant. Dispersions of aqueous capsules in an aqueous medium are also disclosed.

Abstract: A process for the preparation of microcapsules by the condensation of melamine-formaldehyde resins and/or the methyl ethers thereof in water, in which the substantially water-insoluble material forming the core of the capsule is dispersed, in the presence of an anionic protective colloid at pH's of from 3 to 6.5 by the formation of the microcapsules at temperatures of from 20° to 50° C. followed by curing of the shell of the capsules at from >50° to 100° C., in which, prior to curing, from 10 to 200 wt % of urea, whose amino groups are optionally linked to an ethylene or propylene bridge, based on the melamine-formaldehyde resin are added, the microcapsules produced by this process and also the use thereof in a pressure-sensitive recording system.

Abstract: This invention relates to suspension polymers having high swellability have low contents of soluble fractions prepared using aliphatic peroxyesters as polymerization initiators.

Abstract: Briefly, according to one aspect of the invention, liquid crystal material is microencapsulated by a method utilizing an interfacial polymerization reaction which creates a combination of polyurethane and polyurea polymers which form the capsule walls surrounding the discrete liquid crystal droplets. The formed capsule walls are designed to have an adjustable refractive index so as to allow for the matching of the refractive index to that of the liquid crystal and polymeric binder materials. This allows for the production of a liquid crystal droplet surrounded by polymer film, which is optically clear when the liquid crystal director is aligned with the electric field. The microencapsulated liquid crystal droplets improves the dye stability of a dichroic dye and enhances the contrast of a liquid crystal display.