JP2003342095A - Method for producing coated granular bioactive substance - Google Patents

Abstract

(57) [Summary] [Problem] In the production of a coated granular bioactive substance, which requires many functions such as control of elution rate of a bioactive substance, elution pattern, temperature dependency, and degradability of a coating material used, Of the many types of coating materials used, the coating material components (small components) that are used in a small amount are dissipated and mixed in the solvent during the process of dissolving or mixing. As a result, as a result, there occurs a problem that the content of the minor component in the coating of the coating product varies or the content becomes insufficient. Provide a stable production method. A method for producing a coated granular bioactive substance that coats a granular bioactive substance by using a coating material containing a small component and a resin component, comprising the steps of: It is used as a coating material to produce a coated particulate bioactive substance.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a coated granular bioactive substance. More specifically, when many kinds of coating material components are dissolved in a solvent, a small amount of the coating material component among the coating material components is kneaded in advance with the resin component of the coating material component, and then the small amount of the coating material component is mixed. The present invention relates to a method for producing a coated granular bioactive substance, which comprises coating a granular bioactive substance with a kneaded resin component.

[0002]

2. Description of the Related Art Bioactive substances are used for the purpose of prolonging the effect (fertilizing effect, medicinal effect, etc.) of bioactive substances represented by fertilizers, pesticides, pharmaceuticals, bath salts, and supplemental foods, and improving the ease of handling. Granulated bioactive substances (for example, granular fertilizers, pesticide granules, tablets, etc.) obtained by granulating substances are manufactured and used.

In addition, the efficacy of further bioactive substances (fertility,
For the purpose of prolonging the drug efficacy) and controlling the effect expression pattern, coated granular bioactive substances (for example, coated fertilizers, coated pesticides, etc.) in which the surface of the granular bioactive substance is coated with a coating material are produced and used. There is. Among them, a coating material-dissolved mixed solution in which the coating material is dissolved in a solvent is sprayed onto the surface of the granular bioactive substance to form a film on the surface of the granular bioactive substance. The coated granular bioactive substance thus obtained has a high elution rate control function, and is a material that has been drawing attention in recent years.

[0004]

The coated granular bioactive substance comprises:
Many functions such as control of elution rate of bioactive substances, elution pattern, temperature dependence, degradability of used coating materials are required. Therefore, it has been practiced to use a coating material in which various types of coating material components are mixed. However, in this method, in the case of producing a large amount of coated granular bioactive substance, among the various types of coating material components used, the coating material component used in a small amount is dissolved in a solvent,
In the course of mixing, a part of it may be dissipated or adhered to the vessel wall of the melting tank, resulting in variations in the content of the minor component in the coating of the coated product or insufficient content. It has been difficult to stably produce a coated product having a certain function. In the present invention, the minor component means a coating material component whose content in the coating material is 10% by weight or less.

[0005]

[Means for Solving the Problems] The present inventors have conducted extensive studies in order to solve the problems of the prior art. As a result, when many kinds of coating material components are dissolved and mixed in a solvent, a coating material component that is a minor component is kneaded in advance with the resin component of the coating material component, and the minor component is kneaded into the coating material of the resin component. When the ingredients are added to a solvent, dissolved and mixed to prepare a coating material solution mixture, and the solution mixture is sprayed onto the surface of the granular bioactive substance to form a film on the surface of the granular bioactive substance. It has been found that it is possible to stably produce a coated product having a certain function by preventing the variation in the content of the components in the coating and the lack of the content, and completed the present invention based on this finding.

The present invention is shown in the following (1) to (6).

(1) In a method for producing a coated granular bioactive substance, which comprises coating a granular bioactive substance using a coating material containing a minor component and a resin component, a resin obtained by previously kneading the minor component into the resin component. A method for producing a coated granular bioactive substance, which comprises using a component as a coating material.

(2) The method for producing a coated granular bioactive substance according to the above item 1, wherein the resin component is a material containing a thermoplastic resin.

(3) The method for producing a coated granular bioactive substance according to the above item 2, wherein the thermoplastic resin is polyolefin.

(4) The method for producing a coated granular bioactive substance according to the above item 3, wherein the polyolefin is low density polyethylene.

(5) The method for producing a coated granular bioactive substance according to the above item 1, wherein the minor component is a component that accelerates photolysis or thermal decomposition of the resin component.

(6) The method for producing a coated granular bioactive substance according to the above item 1, wherein the minor component is a metal compound.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The bioactive substance in the present invention means (A) agricultural products, useful plants,
What is used for the purpose of raising and protecting plants such as agricultural products, (B) What is used for raising and protecting animals including human beings, and (C) Used in the daily life of human beings and comes into direct contact with the skin. It is a thing.

(A) is for increasing the yield of crops, improving the quality of crops, controlling disease, controlling pests, controlling harmful animals, controlling weeds, and further promoting the growth of crops, suppressing growth, dwarfing, etc. depending on the purpose of use. Specifically, fertilizers, nitrification inhibitors, urease inhibitors, pesticides, microorganisms and the like can be mentioned. Particularly when used as a coated granular bioactive substance, if the bioactive substance is a fertilizer or a pesticide, a relatively high effect can be obtained for its intended purpose.

Specific examples of (B) include medicines such as tablets, pills, granules, and oral preparations, supplemental nutritional foods, livestock feed, and the like, and specific examples of (C) include:
Examples thereof include bath agents, laundry detergents, and molding detergents for drainage pipes and the like.

As the fertilizer, nitrogenous fertilizer, phosphate fertilizer,
In addition to potassium fertilizers, fertilizers containing essential plant elements such as calcium, magnesium, sulfur, iron, trace elements and silicon can be cited. Specific examples of nitrogenous fertilizers include ammonium sulfate, urea, and ammonium nitrate, as well as isobutyraldehyde condensed urea, acetaldehyde condensed urea, and the like. Phosphoric fertilizers include superphosphate lime, fused phosphorus fertilizer, and calcined phosphorus fertilizer. Examples of the potassium fertilizer include potassium sulfate, chloride chloride, and silica silicate fertilizer, and the form thereof is not particularly limited. Further, advanced chemical fertilizer or compound fertilizer having a total amount of the three components of the fertilizer of 30% by weight or more, and further organic fertilizer may be used. Further, a fertilizer to which a pesticide, a nitrification inhibitor, a urease inhibitor, a trace element and the like are added may be used. Especially when it is used for the coated granular bioactive substance, if the granular bioactive substance is urea, a relatively high effect can be obtained for its intended purpose.

As pesticides, disease control agents, pest control agents,
Examples thereof include pest control agents, weed control agents, and plant growth regulators, and any of these can be used without limitation. The disease control agent is an agent used for protecting agricultural crops and the like from harmful effects of pathogenic microorganisms, and mainly includes bactericides. The pest control agent is a chemical agent for controlling pests such as agricultural crops, and is mainly an insecticide. The pest control agent is an agent used for controlling plant parasitic mites, plant parasitic nematodes, field worms, birds and other harmful animals that harm agricultural crops and the like. The weed control agent is a chemical agent used for controlling plants and plants that are harmful to agricultural crops and trees, and is also called a herbicide. The plant growth regulator is a drug used for the purpose of enhancing or suppressing physiological functions of plants.

The pesticide is preferably a solid powder at room temperature, but may be a liquid at room temperature. In the present invention, the pesticide may be water-soluble, sparingly water-soluble, or water-insoluble, and is not particularly limited. Specific examples of the pesticides are shown below, but these are merely examples and the present invention is not limited thereto. Also, even if there is only one pesticide,
It may be composed of two or more kinds of composite components.

Further, examples of pesticides include substances that induce phytoalexin, which is a low-molecular weight antibacterial substance that is synthesized by plants after contact with plants and accumulates in the plants.

The nitrification inhibitor is a substance that suppresses nitrification of ammonia nitrogen by nitrifying bacteria. Specifically, dicyandiamide, thiourea, 2
-Amino-4-chloro-6-methylpyrimidine, 2-mercaptobenzothiazole, sulfathiazole, guanylthiourea, N-2,5-dichlorophenylsuccinamic acid, 4-amino-1,2,4-triazole hydrochloride, 2-[(N-nitro) methylamino-1,3,4-
Thiadiazole, 5-mercapto-1,3,4-triazole, 2-chloro-6- (trichloromethyl) pyridine, trichloromethylmethylaminotriazine, 2,4
-Dichloroaniline, 2-trichloromethylquinoline, etc. can be mentioned. Among them, dicyandiamide has high solubility in water and is inexpensive,
It can be preferably used in the present invention.

The urease inhibitor is not particularly limited as long as it has a urease inhibitory effect such as phosphoric acid triamide, but N-alkylthiophosphoric acid triamide is preferable in terms of the urease inhibitory effect, and among them, N- ( n-
Butyl) thiophosphoric acid triamide is particularly effective.

As the microorganisms, those having an effect of suppressing the propagation of pathogenic microorganisms can be used. Specifically, filamentous fungi such as Trichoderma, Gliocladium, Cephalosporium, Coniocillium, Sporidesmium, Laetitharia, etc., Agrobacterium, Bacillus, Pseudomonas, Xanthomonas, Erwinia, Erslo. Bacter, Corynebacterium, Enterobacter, Azotobacter, Flavobacterium, Streptomyces, Actinoplanes,
Alcaligenes, Amorphosporangium, Cellulomonas, Micromonospora, Pasteuria,
Bacteria and actinomycetes such as Hafnia, Rhizobium, Bradyrhizobium, Serratia, and Rustonia can be mentioned.

In particular, the CDU-degrading bacteria group (Pseudomonas spp.
Strains of the genus Arthrobacter, the genus Corynebacterium, the genus Agrobacterium, etc. and the genus Streptomyces (for example, Micromachine Research Deposit No. 10533 disclosed in Japanese Examined Patent Publication No. 5-26462) are soil-borne pathogenic agents. It is preferably used because it has a remarkable deterrent against filamentous fungi.

The composition of the granular bioactive substance used in the present invention is not particularly limited as long as it contains at least one bioactive substance. The bioactive substance may be granulated alone, and granulated using a carrier such as clay, kaolin, talc, bentonite, or calcium carbonate, or a binder such as polyvinyl alcohol, sodium carboxymethyl cellulose, or starch. It can be one. Also, if necessary, for example, a surfactant containing polyoxyethylene nonylphenyl ether, molasses, animal oil, vegetable oil, hydrogenated oil, fatty acid, fatty acid metal salt, paraffin, wax, glycerin, etc. may be contained. I do not care.

The method for granulating the granular bioactive substance is as follows:
An extrusion granulation method, a fluidized bed granulation method, a tumbling granulation method, a compression granulation method, a coating granulation method, an adsorption granulation method and the like can be used.
In the present invention, any of these granulation methods may be used, but the extrusion granulation method is the simplest.

The particle size of the granular bioactive substance is not particularly limited, but in the case of fertilizer, for example, 1.
0 to 10.0 mm, 0.3 in the case of pesticides
It is preferably about 3.0 mm. By using a sieve, an arbitrary particle size can be selected within the above range.

The shape of the granular bioactive substance is not particularly limited, but is preferably spherical in the present invention. Specifically, a circularity coefficient, which is a measure for knowing the circularity of particles, may be used, and is calculated by the formula {(4π × projection area of particles) / (contour length of particle projection diagram) ² }. The value is preferably 0.85 or more, more preferably 0.9 or more, still more preferably 0.93 or more. The maximum value of the circularity coefficient is 1, and as the value approaches 1, the particle approaches a perfect circle, and the circularity coefficient decreases as the shape of the particle collapses from the perfect circle.

The coating material used in the present invention is not particularly limited as long as it is a material containing a resin component capable of forming a film on the surface of the granular bioactive substance.

The resin used for the coating material is not particularly limited, and examples thereof include thermoplastic resin, thermosetting resin and emulsion. As a thermoplastic resin,
Specific examples thereof include olefin polymers, vinylidene chloride polymers, diene polymers, waxes, polyesters, petroleum resins, natural resins, fats and oils and modified products thereof, and urethane resins.

Specific examples of the thermoplastic resin include olefin polymers, vinylidene chloride polymers, diene polymers, waxes, polyesters, petroleum resins, natural resins,
Examples thereof include fats and oils and modified products thereof. Examples of the olefin polymer include polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-carbon monoxide copolymer, ethylene-hexene copolymer, ethylene-butene copolymer, ethylene-butadiene copolymer, polybutene. , Butene-ethylene copolymer, butene-propylene copolymer, polystyrene, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-carbon monoxide copolymer,
Examples thereof include ethylene-acrylic acid copolymers and ethylene-methacrylic acid ester copolymers, and examples of vinylidene chloride-based polymers include vinylidene chloride-vinyl chloride copolymers. Here, polyethylene is
High density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDP)
E) or ultra low density polyethylene may be used, and the melt flow rate, molecular weight, molecular weight distribution, etc. are not particularly limited.

Examples of the diene polymer include butadiene polymer, isoprene polymer, chloroprene polymer, butadiene-styrene copolymer, EPDM polymer, styrene-isoprene copolymer and butadiene-ethylene-methacrylic acid. An example is a terpolymer.

Examples of the waxes include beeswax, wood wax, paraffin, etc., examples of the polyester include aliphatic polyesters such as polylactic acid and polycaprolactone, and aromatic polyesters such as polyethylene terephthalate, and examples of the natural resin include: Examples thereof include natural rubber and rosin, and examples of fats and oils and modified products thereof include cured products, solid fatty acids and metal salts.

As the thermosetting resin, phenol resin,
Furan resin, xylene-formaldehyde resin, ketone formaldehyde resin, amino resin, alkyd resin, unsaturated polyester, epoxy resin, silicon resin, urethane resin, and drying oil can be mentioned. These thermosetting resins have many combinations of monomers, but the types and combinations of the monomers are not limited in the present invention. Further, in addition to a polymer of monomers, a polymer of a dimer or a polymer, or a mixture thereof may be used. Further, a mixture of a plurality of different types of resins may be used. When the thermosetting resin is used as the coating resin component, the minor component is added to and mixed with the total amount of the prepolymer of the thermosetting resin to be used to prepare a coating material, which is used for coating.

The alkyd resin may be either non-conversion type or conversion type, and linseed oil, soybean oil, perilla oil, fish oil, tung oil,
Sunflower oil, walnut oil, deer oil, castor oil, dehydrated castor oil, distilled fatty acids, cottonseed oil, coconut oil, and their fatty acids, or fatty oils such as monoglycerides transesterified with glycerin, or alkyd resins modified with fatty acids are also used. it can.

Particularly, in the case of a coated granular bioactive substance having a time-release type sustained release function, when a long release suppression period is required, it is effective to form a film having a small moisture permeability on the surface of the granular bioactive substance. Is. By forming a resin film having a low moisture permeability on the surface of the granular bioactive substance, it is possible to gradually permeate the water present outside to the particles containing the bioactive substance.

To this end, it is effective to coat the granular bioactive substance with a coating material containing a thermoplastic resin having a low moisture permeability, and further, as the thermoplastic resin, an olefin polymer, an olefin copolymer, a chloride Vinylidene polymer,
It is effective to use a vinylidene chloride copolymer. In particular, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-carbon monoxide copolymer, ethylene-hexene copolymer, ethylene-butene copolymer, propylene-butene copolymer, ethylene-vinyl acetate copolymer And mixtures thereof can be mentioned as the most preferred resin component of the coating material. If a film without pinholes or cracks is formed using these resin components, the amount of water permeation becomes extremely small.

In order to control the moisture permeability of the coating, a resin having a high moisture permeability and a filler can be mixed and used as a coating material. As the resin having high moisture permeability, polyethylene oxide, polypropylene oxide, ethylene-
Resins having polar groups such as vinyl acetate copolymers introduced, ethylene-propylene copolymers, styrene-isoprene copolymers, polystyrene-polyisoprene-polystyrene block copolymers, polystyrene-polybutadiene block copolymers, polystyrene-polybutadiene Examples thereof include rubbery resins such as hydrogenated block copolymers.

The coating material used in the present invention includes, in addition to the resin coating material described above, additives such as a filler, a surfactant for imparting hydrophilicity, an ultraviolet absorber, an antistatic agent, a plasticizer, and the like. A slip material such as an aliphatic amide or an anti-blocking material such as silica can be used. These fillers and additives are used together with coating materials such as resin components. Examples of the filler include talc, clay, kaolin, bentonite, sulfur, muscovite, phlogopite, mica-like iron oxide, metal oxides, metal salts of metals with organic acids or nitric acid, metal complexes, siliceous materials, glasses, alkalis. Earth metal carbonates,
Or sulfate, and cellulose, a cellulose compound,
Examples thereof include starches and sulfur, and examples of the surfactant include nonionic surfactants represented by fatty acid esters of polyols. In the present invention, two or more kinds of the coating materials may be used in combination depending on the release function required for the coated granular bioactive substance.

In the coating material containing a resin, the content ratio of the resin is preferably in the range of 10 to less than 100% by weight, more preferably 20 to 100% by weight based on the coating material.
It is in the range of less than 100% by weight. Further, in the coating material containing an inorganic substance such as sulfur, the content ratio of the inorganic substance is preferably 10 to 90% by weight, more preferably 20 to 80% by weight, based on the coating material. Is.

The coating ratio of the coating material in the coated granular bioactive substance of the present invention is 3 with respect to the coated granular bioactive substance.
It is preferably in the range of 20 to 20% by weight, more preferably in the range of 5 to 12% by weight.

Among the coating material components used in the present invention, a small amount of the coating material component is a metal oxide which is an additive for promoting photodecomposition, thermal decomposition, oxidative decomposition and biodegradation of the resin component of the coating material. , Metal salt of metal with organic acid or nitric acid,
There are metal complexes, radical generators, photosensitizers, etc., and other urease inhibitors, nitrification inhibitors, agricultural chemicals, trace element fertilizers, moisture absorbents such as calcium carbonate, water swelling agents, surfactants, beeswax, wood wax. , Wax such as paraffin,
Fatty oils or fatty acids, isocyanates, amines, compatibilizers, biodegradable resins, and finely divided particles such as cellulose, glass fiber, starch, potassium sulfate, cyclodiurea, and isobutylidene urea as fillers added in a small amount. Can be mentioned.

Particularly, in the environment where the coated granular bioactive substance is used, many components added to accelerate the decomposition of the resin component in the coating material exert a small amount of effect, and the effect of the present invention is obtained. Remarkably appears. Decomposition includes photodecomposition and thermal decomposition, and oxidative decomposition and radical decomposition are used. A metal compound is often used as a component used for these.

Examples of metal oxides include iron oxide, aluminum oxide, manganese oxide, calcium oxide, magnesium oxide and the like. Examples of the metal salt include iron stearate, tin octylate, cobalt naphthenate, manganese naphthenate, ferrous sulfate, ferric sulfate, iron nitrate, cobalt acetate and the like, and boron trifluoride and the like. Can be used.

As the metal complex, acetylacetone iron,
Examples thereof include cobalt acetate, cobalt naphthenate, manganese naphthenate, and dibutyldithiocarbamate nickel.

As the radical generator, benzoylper
Examples thereof include oxides, azobisisobuturonitrile, polyfuran, polyisoprene, hydroxyphthalimides and the like.

Examples of the photosensitizer include benzophenone, tetracyanobenzene, silver halide and chlorophyll.

The urease inhibitor, nitrification inhibitor, pesticide, and trace element fertilizer are the same as those exemplified as the biologically active substance. Examples of the moisture absorbent include calcium carbonate, calcium chloride, calcium oxide, magnesium chloride and the like.

As the water swelling material, an acrylate polymer (for example, Sumikagel (registered trademark) S, L, R types manufactured by Sumitomo Chemical Co., Ltd., Aqua Keep (registered trademark) manufactured by Sumitomo Seika Chemicals, Ltd.) ) 10SH, 10SHP, 10SH-NF
(20), SA60NTYPE2, Aquamate (registered trademark) AQ-200, A manufactured by Sekisui Plastics Co., Ltd.
Q-200B-02, Sunfresh (registered trademark) ST-500D, ST-500MP manufactured by Sanyo Chemical Industries, Ltd.
S), an isobutylene-based polymer (for example, registered trademark KI gel-201K, KI gel-201K manufactured by Kuraray Co., Ltd.)
-F2, KI gel solution system, KI gel compound), acrylic acid / vinyl alcohol copolymer, polyethylene oxide modified resin, starch graft polymer (for example, Sunfresh (registered trademark) ST-manufactured by Sanyo Kasei Co., Ltd.) 100, ST-500S, ST-100MP
S), starch (for example, potato starch, corn starch,
Examples include sweet potato starch, soluble starch), carboxymethyl cellulose (CMC), CMC metal salts and bentonite.

As the surfactant, higher fatty acid salts, higher alkyl dicarboxylic acid salts, higher alcohol sulfate ester salts, higher alkyl sulfonates, higher alkyl disulphonates, sulfonated higher fatty acid salts, higher alkyl phosphate ester salts Examples thereof include anionic surfactants such as cations, higher alkyl amine salts, cationic surfactants such as quaternary ammonium salts, fatty acid esters of polyols, and nonionic surfactants such as polyethylene oxide condensation type.

Examples of the wax include dense wax, wooden wax, paraffin and the like. Examples of the fat oil or fatty acid include linseed oil, soybean oil, sesame oil, fish oil, tung oil, sunflower oil, walnut oil, eucalyptus oil, castor oil, dehydrated castor oil, distilled fatty acid, cottonseed oil, coconut oil, and those fatty acids, or Mention may be made of monoglycerides transesterified with glycerin. In addition, resin modified products such as rosin, ester rosin, copal, and phenol resin can also be used.

The isocyanates are the same as those exemplified for the urethane resin of the coating material. It is used for the purpose of increasing the molecular weight of urethane resin or aliphatic polyester.

Examples of amines include ethylenediamine and dicyandiamide.

Examples of the compatibilizing agent include styrene / ethylene / butadiene block copolymer, ethylene / methyl methacrylate block copolymer, polyethylene / polystyrene graft copolymer, polyethylene / polymethylmethyl methacrylate graft copolymer, ethylene / acetic acid. Vinyl copolymer, ethylene / propylene / diene copolymer,
Examples thereof include styrene / ethylene / butadiene / styrene copolymers.

Examples of biodegradable resins include polylactic acid and polycaprolactone. The coating material of these minor components is appropriately selected and used according to the function required for the coated granular bioactive substance.

The coating of the coating material on the surface of the granular bioactive substance of the present invention is carried out by dissolving and mixing the coating material in a solvent.
A method for forming a film on the surface of a granular bioactive substance by spraying a coating material-dissolved mixed solution obtained by dissolving a small amount of coating material component in a solvent in a sealed state ( Hereinafter, the effect will be remarkable in the case of the solution mixture spray method). From the viewpoint of high production efficiency and uniformity of the obtained coating film, the coating material-dissolved mixed liquid is applied to the granular bioactive substance in a rolling or flowing state by spraying, and then the coating film is exposed by hot air. The method of forming is preferred.

An example of a coating apparatus that can be used in the dissolved mixed solution spraying method will be described with reference to the jet apparatus shown in FIG. In the method, in order to uniformly disperse the solvent-insoluble coating material such as an inorganic filler in the coating material-dissolved mixed liquid, it is necessary to strongly stir the coating material-dissolved mixed liquid.

This jetting apparatus transports the coating material-dissolved mixed solution to the jetted particles 3 through the pipe 5, sprays them with the spray nozzle 2 and sprays them onto the surfaces of the particles 3 to coat the surfaces. At the same time, a high-temperature gas is introduced into the jet tower 1 from the lower part into the guide tube 6, and the high-speed hot air flow instantly evaporates and dries the solvent in the coating material-dissolved mixed liquid adhering to the surface of the particles. Is. The spraying time varies depending on the resin concentration of the coating material-dissolved mixed solution, the spray rate of the solution, the coating rate, etc., but these should be appropriately selected according to the purpose.

As a coating apparatus other than the jet apparatus shown in FIG. 1 which can be used in the present invention, a fluidized bed type or jet layer type coating apparatus is disclosed in Japanese Examined Patent Publication Nos. 42-24281 and 42-24282. A device for forming a fountain-type fluidized bed of particles by a gas body and spraying a coating agent on a particle dispersion layer generated in the central part can be mentioned as a rotary type coating device.
Japanese Patent Laid-Open No. 7-195007 and Japanese Patent Laid-Open No. 7-195007, a lifter provided on the inner circumference of a drum by rotating the drum transfers the powder particles upward, and then drops the powder particles to apply a coating agent to the surface of the falling particles. However, an apparatus for forming a film can be used.

When a coated granular bioactive substance is obtained by the dissolution mixed solution spraying method, the solvent used is not particularly limited, but since the solubility characteristics for each solvent differ depending on the type of resin used for coating, The solvent may be selected according to the resin used. For example, when using an olefin polymer, an olefin copolymer, a vinylidene chloride polymer, a vinylidene chloride copolymer or the like as a resin, a chlorine-based solvent or a hydrocarbon-based solvent is preferable, and among them, tetrachloroethylene, trichloroethylene, and toluene are used. If it is present, it is a particularly preferable solvent because a dense and uniform film can be obtained.

In the conventional dissolution mixed solution spraying method, in the step of dissolving the coating material in the solvent, a small amount of the coating material solidifies due to moisture absorption by steam or air moisture due to heating of the solvent, or adheres to the dissolution container. Due to factors such as the above, the content of minor components may not be constant in the product. Particularly when a plurality of coating material components are mixed and used, a small amount of coating material component is weighed and mixed with a large amount of other coating material components at the same time,
When dissolved, it was difficult to reliably add, dissolve, and mix a fixed amount because the coating material component of a small amount may be scattered.

The present invention makes it possible to dissolve and mix the small amount of the coating material component in the coating material solution at a constant concentration with little variation, and to add a small amount in the process of mixing the coating material with the solvent. The coating material component of the component is mixed in advance with the coating material component of the resin component among the coating material components, and is added to the solvent to be dissolved and mixed, whereby the coating material component is uniformly mixed.

The resin component in which the minor component coating material component is mixed is not particularly limited as long as it is a material used for coating.

When the minor component is liquid and the resin component is solid, it is preferably a material which can be uniformly blended by adsorption, impregnation or swelling. In this case, the resin component preferably has a large surface area such as powder.

Further, a method of melting the resin component and mixing it with a small amount component and then charging it into a dissolution tank for the coating material, or a method of melting the resin component and mixing it with the small amount component and then once cooling and solidifying the melt may be used. it can. In order to prevent a small amount of components from separating on the surface of the resin component from the cooled solidified product, it is preferable to select a combination having high compatibility and to take measures such as storage in a cold place. When both the minor component and the resin component are liquid, it is preferable to select a material that can be uniformly mixed due to its high compatibility.

When the minor component is solid and the resin component is solid, it is preferable to be able to perform melt mixing. In this case, it is preferable to select a material that does not cause deterioration such as thermal decomposition, and an antioxidant, a stabilizer or the like can be added to prevent deterioration. When viscosity is generated due to overheating such as melting and adheres to a melting machine or a mixer, it is possible to prevent the adhesion by applying a small amount of the release material to the coating composition of the release material or a mixed component. These additives are preferably added in such an amount that does not impair the function of controlling the elution rate of the coated granular bioactive substance. It is preferable to select a material that can be uniformly mixed due to high compatibility between the small amount component and the resin component.

When the minor component is solid and the resin component is liquid, the resin component is preferably a liquid capable of dissolving the minor component. Alternatively, it is preferable that a trace amount component can be dispersed or mixed in the resin component.

When the resin components are mixed after melting, they can be used at a temperature at which the resin softens and can be mixed. The higher the temperature, the lower the viscosity of the melt and the easier the uniform mixing, but the resin or a small amount of components may be deteriorated by heat such as decomposition, oxidation and modification. It is preferable to perform melt mixing at a temperature at which thermal deterioration does not occur.

It is possible to add a stabilizer for avoiding thermal deterioration during melt mixing. An antioxidant is often used as the stabilizer. Antioxidants include 2,6-
Di-t-butyl-4-methylphenol, 2,2'-methylenebis (4-methyl-6-t-butylphenol),
1,3,5-trimethyl-2,4,6-tris (3,5
-Di-t-butyl-4-hydroxybenzyl) benzene and other phenols, dilaurylthiodipropionate,
Sulfides such as distearyl thiodipropionate,
Examples thereof include phosphites such as tridecyl phosphite and diphenyldecyl phosphite, and metal complexes such as nickel dibutyldithiocarbamate. Further, the antioxidant is preferably a low-volatile substance, and can be used in combination with an additive having a peroxide decomposing ability such as dilaurylthiodipropionate.

When the trace substance is a metal compound, a phosphite type antioxidant is not a preferable choice because it inhibits the activity of the metal compound.

As the additive, it is preferable to use a material that does not affect the control of the elution rate of the coated granular bioactive substance, or a material that does not easily affect the control. The amount of addition that allows control of the elution rate is selected by blending the coating material. It is preferable.

Additives may detach from the coating during storage or application of the coated particulate bioactive material. Therefore, the elution rate may change. It is preferable to select an additive having high compatibility with the resin component or to keep the addition amount to a necessary minimum.

A method such as an extruder using a screw can be used for the melt mixing. Pelletizing the molten mixture using a granulator is preferable because it facilitates the measurement and dissolution when the coating material is dissolved. Even in this case, it is necessary to give sufficient consideration to heat deterioration.

In any case, when the mixing is insufficient, when the coating material is weighed and dissolved in the solution, the input amount varies, and it becomes impossible to produce a coated granular bioactive substance of stable quality. . Sufficient intimate mixing is preferred to produce a stable quality coated particulate bioactive material.

A dispersant can be used to perform sufficient uniform mixing. Examples of the dispersant include a surfactant, a compatibilizer, and metal soap. Examples of the metallic soap include zinc stearate, calcium stearate, aluminum stearate and the like. Also in this case, it is preferable to give sufficient consideration to the influence of the addition of the dispersant on the elution rate of the coated granular bioactive substance.

[0075]

EXAMPLES The present invention will be described below with reference to examples. In addition, "%" in the following examples is "% by weight" unless otherwise specified.

Examples 1 to 5 A method of coating using granular urea classified with a sieve having a particle size of 2.5 to 3.5 mm will be described. The coating device used is shown in FIG. Tower diameter 250 mm, height 2000 m
m, the diameter of the air outlet was 50 mm, and the hot hot air flowed from the lower part to the upper part into the jet tower 1 having a shape of a cone angle of 50 degrees. The high-temperature hot air is blown from the blower 10, passes through the orifice flow meter 9, is heated to a high temperature by the heat exchanger 8 and flows into the jet tower 1, and is discharged from the exhaust gas outlet 3 installed at the upper part of the jet tower 1. It Inside the jet tower 1 in which this high-temperature hot air is circulated, 10 kg of the granular bioactive substance is introduced from an inlet 2 provided on the side surface of the jet tower 1, and the granular bioactive substance 5 is introduced as shown in FIG. To flow. At this time, the flow rate of hot air and the hot air temperature need to be appropriately adjusted for each granular fertilizer, and the flow rate is adjusted while measuring with an orifice flow meter, and the hot air temperature is T1 hot air temperature, T2 granule temperature, Adjust while measuring the exhaust temperature of T3.

In the present embodiment, the flow rate (orifice flow meter 9) 4 m ³ / min, hot air temperature (hot air temperature T1) 10
0 ° C ± 2 ° C, granular urea temperature (particle temperature T2) 70 ± 2 ° C
It was carried out in. On the other hand, polyethylene (low-density polyethylene powder d = 0.918 [g / cm ³ ] (density
JIS K6760), MFR = 22 [g / 10 min] (melt flow rate JIS K6760)) 60 parts by weight, ethylene-vinyl acetate copolymer (MI = 20 [g / 10 min]
(Melt indexes JIS K6760), vinyl acetate content 30% by weight 39.9 parts by weight, iron stearate (reagent product fine powder) 0.1 parts by weight, and solvent tetrachloroethylene 70 liters were previously charged. When added to the dissolution tank 11, 0.1 part by weight of the iron stearate (reagent product fine powder), which is a minor component in the coating agent, is a polyethylene (low density polyethylene powder) which is a major component.
d = 0.918 [g / cm ³ ] (density JIS K6760), MFR = 22
[G / 10min] (Melt flow rate JIS K676
0)) 60 parts by weight were mixed and uniformly mixed by a Henschel mixer (trade name), and the resulting mixture was melt-kneaded by an extruder and then pelletized. 100 ° C
Dissolve the resin by mixing and stirring at ± 2 ° C to
A 5 wt% uniform coating material dissolved mixture 12 was obtained.

The dissolution tank 11 was constantly stirred until the coating was completed. The coating material-dissolved mixed liquid 12 is flown by a pump 6 to a spray nozzle 4 which is a 0.8 mm full-confluent type one-fluid nozzle installed at the bottom of the jet tower 1 at a flow rate of 0.1
It was transported at a rate of kg / min, and sprayed on the flowing granular urea 5 by spraying. At this time, the dissolution tank 11 and the dissolution tank 11 are kept so that the temperature of the coating material dissolution mixture 12 does not fall below 80 ° C.
The pipe from the nozzle to the spray nozzle 4 was made into a double structure, and the coating material-dissolved mixed liquid 12 was transported while heating while passing steam.

The above-mentioned coating operation is started when the particle temperature T2 of the flowing granular urea 5 reaches 70 ° C., and the predetermined coating is performed until the coating becomes 8.5% by weight based on the coated granular bioactive substance. After spraying for a period of time, the coated granular bioactive substance was maintained at 70 ° C. ± 2 ° C., while controlling the temperature of the hot air, drying was performed by blowing only hot air for 10 minutes. At the time of completion, the blower 10 was stopped, and the coated granular bioactive substance 5 was discharged from the outlet 7 at the bottom of the jet tower 1 to obtain the coated granular bioactive substance of Example 1 shown in Table 1. It was This operation was repeated 4 times to obtain the coated granular bioactive substances of Examples 2 to 5 shown in Table 1.

Coating operation conditions One-fluid nozzle: outlet diameter 0.8 mm, full-corn type granular fertilizer: 10 kg Hot air temperature: 100 to 110 ° C. Hot air flow rate: 240 m ³ / hr Spray flow rate: 0.5 kg / min

Examples 6 to 10 Examples 1 to 10 except that 20 liters, which is a part of tetrachloroethylene, which is a solvent, was used as a major component, and the entire amount of iron stearate, which is a minor component, was dissolved in advance to form a mixture.
According to 5, the coated granular bioactive substances of Examples 6 to 10 shown in Table 1 were obtained.

Comparative Examples 1 to 5 Coated granular bioactive substances were prepared according to Examples 1 to 5 except that iron stearate was not charged and was directly charged into a dissolution tank.

Method for calculating theoretical value of iron content Iron content determined from the coating material composition ratio in 5 g of coated granular bioactive substances of Examples 1 to 10 and Comparative Examples 1 to 5. Iron stearate [CH ₃ (CH ₂ ) ₁₆ COO] ₃ Fe:
Molecular weight 906.25 Atomic weight of iron: 55.85 Iron content theoretical value = (5.0 × 0.085 × 0.1 × 55.85 / 906.25) /5.0×10 ⁶ = 523.8 [ppm]

Method of Analyzing Measured Iron Content in Coating Film 5 g of each of the coated granular bioactive substances prepared in Examples 1 to 5 and Comparative Examples 1 to 5 was dissolved in 100 ml of toluene, and the dissolved solution was contained by flame photometry. The iron content was measured and listed in Table 1.

[0085]

[Table 1]

As is clear from the results in Table 1, in Examples 1 to 10 in which a small amount of coating material component was kneaded into the resin component, Comparative Examples 1 to 5 in which the small amount coating material component was not kneaded.
It was confirmed that it was possible to manufacture a product with less variation in the measured iron content in the coating film and a smaller difference from the theoretical iron content compared to.

[0087]

According to the production method of the present invention, a coating material containing a minor component and a resin component is used to coat a granular bioactive substance with a coating material. Since the resin component kneaded into the resin component is dissolved and mixed in a solvent together with other coating material components, it is possible to reduce the variation in the content of the minor component in the coating film of the obtained coated granular bioactive substance. ,And,
It is possible to obtain a coated granular bioactive substance having a content with a small difference from the theoretical value.

[Brief description of drawings]

FIG. 1 Diagram of a spouted bed flow sheet

[Explanation of symbols]

1. Spout tower 2. Granule input port 3. Exhaust gas outlet 4. spray nozzle 5. Granular bioactive substance 6. pump 7. Outlet 8. Heat exchanger 9. Orifice flow meter 10. Blower 11. Melting vessel 12. Dissolution mixture of coating material T1. Hot air thermometer T2. Granule thermometer T3. Exhaust thermometer SL. steam

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) A61K 47/30 A61K 47/30 47/32 47/32

Claims (6)

[Claims] 1. A method of producing a coated granular bioactive substance, which comprises coating a granular bioactive substance with a coating material containing a minor component and a resin component. A method for producing a coated granular bioactive substance, characterized by using as a coating material. 2. The method for producing a coated granular bioactive substance according to claim 1, wherein the resin component is a material containing a thermoplastic resin. 3. The method for producing a coated granular bioactive substance according to claim 2, wherein the thermoplastic resin is polyolefin. 4. The method for producing a coated granular bioactive substance according to claim 3, wherein the polyolefin is low density polyethylene. 5. The method for producing a coated granular bioactive substance according to claim 1, wherein the minor component is a component that accelerates photolysis or thermal decomposition of the resin component. 6. The method for producing a coated granular bioactive substance according to claim 1, wherein the minor component is a metal compound.