JP2004300022A - Coated granular fertilizer and production method thereof - Google Patents

Abstract

【Task】
Provided is a coated granular fertilizer in which a shell of a coating material after elution of a fertilizer component hardly floats on the water surface, and a method for producing the same.
[Solution]
A coated granular fertilizer having an inner core made of granular fertilizer, a first coating layer made of iron oxide, and a second coating layer made of a thermosetting resin adjacent to the outside of the first coating layer made of iron oxide; A step of adding finely powdered iron oxide to the granular fertilizer in a moving state, uniformly dispersing, maintaining a rolling state until a coated state is obtained, and obtaining an iron oxide coating of the granular fertilizer; and After adding the liquid uncured thermosetting resin to the iron oxide coating, the surface of the iron oxide coating is coated with the uncured thermosetting resin while maintaining the rolling state, and then the uncured thermosetting resin is applied. Obtaining a thermosetting resin coating by thermosetting the resin.
[Selection diagram] None

Description

  The present invention relates to a coated granular fertilizer in which the water buoyancy of a shell after elution of a fertilizer is suppressed, and a method for producing the same.

Coated granular fertilizers obtained by coating a granular fertilizer with a resin or the like are widely used from the viewpoint of labor saving of agricultural work and the like, but these coated granular fertilizers sometimes leave a shell of the coating material after the fertilizer component elutes. Then, there has been a case where a problem that the shell of the covering material floats on the water surface at the time of cultivation in the following year in a paddy field or the like occurs.
On the other hand, as a technique for suppressing the shell of the covering material from floating on the water surface, a technique described in Patent Literature 1 is known.

JP-A-2002-249392

  An object of the present invention is to provide a coated granular fertilizer in which the shell of the coating material after elution of the fertilizer component is unlikely to float on the water surface.

  The present inventor has conducted intensive studies in order to provide a coated granular fertilizer in which the shell of the coating material after elution of the fertilizer component is difficult to float on the water surface. And a coated granular fertilizer having a second coating layer made of a thermosetting resin adjacent to the outside of the first coating layer made of iron oxide, the shell of the coating agent remaining after elution of the fertilizer component is difficult to float on the water surface. Heading, the present invention has been completed.

That is, the present invention is as follows.
1. A coated granular fertilizer having an inner core made of a granular fertilizer, a first coating layer made of iron oxide, and a second coating layer made of a thermosetting resin adjacent to the outside of the first coating layer made of iron oxide.
2. 1. The granular fertilizer is granular urea. A coated granular fertilizer according to the above.
3. 1. The thermosetting resin is a urethane resin. Or 2. A coated granular fertilizer according to the above.
4. Rolling granular fertilizer, adding fine powdered iron oxide, uniformly dispersed, maintaining the rolling state until the coated state, to obtain an iron oxide coating of the granular fertilizer, and the rolling state After adding a liquid uncured thermosetting resin to the iron oxide coating, the surface of the iron oxide coating is coated with the uncured thermosetting resin while maintaining the rolling state, and then the uncured thermosetting resin is applied. Obtaining a thermosetting resin coating by thermosetting a thermosetting resin.

  In the coated granular fertilizer of the present invention, the shell of the coating agent remaining after elution of the fertilizer component is unlikely to float on the water surface.

  The coated granular fertilizer of the present invention comprises an inner core made of granular fertilizer, a first coating layer made of iron oxide, and a second coating layer made of a thermosetting resin adjacent to the outside of the first coating layer made of iron oxide. It has.

The granular fertilizer in the present invention is a granular material containing a fertilizer component. The fertilizer component is a component containing various elements such as nitrogen, phosphorus, potassium, silicon, magnesium, calcium, manganese, and boron, which are applied to soil to provide nutrients in plant cultivation such as paddy rice. Is urea, ammonium nitrate, ammonium nitrate, ammonium chloride, ammonium sulfate, ammonium phosphate, sodium nitrate, calcium nitrate, potassium nitrate, lime nitrogen, formaldehyde processed urea fertilizer (UF), acetaldehyde processed urea fertilizer (CDU), isobutyraldehyde processed Nitrogenous fertilizers such as urea fertilizer (IBDU) and guanyl urea (GU); lime superphosphate, lime heavy superphosphate, fused phosphorus fertilizer, humic acid phosphorus fertilizer, calcined phosphorus fertilizer, heavy phosphorus phosphatase, phosphorus over clay Acid, ammonium polyphosphate, potassium metaphosphate, calcium metaphosphate, Phosphate fertilizers such as soil phosphoric acid, ammonium phosphate, potassium phosphate nitrate, phosphorous ammonium salt; potassium fertilizers such as potassium chloride, potassium sulfate, potassium sulfate, potassium sulfate, potassium bicarbonate, potassium phosphate; silicic acid Silicic fertilizers such as calcium; magnesium fertilizers such as magnesium sulfate and magnesium chloride; calcium fertilizers such as quicklime, slaked lime and calcium carbonate; Examples of common fertilizers (including compound fertilizers) specified in the Fertilizer Control Law, such as boronic fertilizers such as acid salts, can be given. Among them, those containing at least one fertilizer component selected from nitrogen (N), phosphorus (P) and potassium (K), particularly those containing all three fertilizer components, are preferred. Specific examples, NPK-component _{(N-P 2 O 5 -K} 2 O) include fertilizers, as such fertilizers _{such, 5-5-7 (N-P 2 O} 5 -K 2 O in Weight ratio means the same hereafter), 1 type flat type such as 12-12-16, 2 type horizontal type such as 5-5-5 and 14-14-14, 6-6-5, 8- 3-5 flat type such as 8-5, 4 type upward type such as 4-7-9 and 6-8-11, 5 type upward flat type such as 4-7-7 and 10-20-20, 4- 6-type mountain type such as 7-4 and 6-9-6, 7-type valley type such as 6-4-5 and 14-10-13, and 8-type lowering such as 6-5-5 and 18-11-11 Flat type, 9 type down type such as 7-6-5, 14-12-9, etc., 10 type NP type such as 3-20-0, 18-35-0, 16-0-12, 18-0-16 11 type NK type, 0-3-14, 0-15-15 It includes 12-inch PK type is.

These fertilizer components can also contain pesticidally active compounds.
The particle diameter (equivalent circular diameter) of the granular fertilizer is usually in the range of 1 to 5 mm from the viewpoint of production.

In the present invention, a granular fertilizer coated with a hydrophobic compound can be used as the inner core, and a granular fertilizer coated with a thermosetting resin (for example, a urethane resin) can be used as the inner core. That is, the granular fertilizer in the present invention includes a granular fertilizer coated with a hydrophobic compound and a granular fertilizer coated with a thermosetting resin.
The hydrophobic compound in this case is usually a solid at ordinary temperature, and its melting point or softening point is usually 40 to 120 ° C, preferably 50 to 100 ° C, and more preferably 50 to 100 ° C in view of industrial production. Preferably it is 60-90 degreeC.

  Examples of the hydrophobic compound include a wax, a fatty acid, a fatty acid salt, a fatty acid ester, a higher alcohol, and a silicone. These may be a mixture of two or more kinds.

Examples of the wax include animal waxes such as beeswax; vegetable waxes such as carbana wax; mineral waxes such as montan wax; petroleum waxes such as microcrystalline wax, semicrystalline wax, and paraffin wax; Compound wax obtained by polymerizing at least two kinds of monomers such as ethylene, propylene and acrylic acid; and synthetic wax such as Fischer-Tropsch wax. Can be Examples of fatty acids include C12-18 aliphatic carboxylic acids such as lauric acid and stearic acid, and examples of fatty acid salts include alkali metal salts and alkaline earth metal salts of the fatty carboxylic acids.
Examples of the fatty acid ester include an ester of a C12-18 aliphatic carboxylic acid and glycerin, a hardened castor oil obtained by hydrogenating castor oil, and a hardened oil obtained by hydrogenating beef tallow. Higher alcohols include C16-20 alcohols such as stearyl alcohol.
Examples of the silicone include silicone grease such as polydimethylsiloxane, and silicone rubber.

The amount of the hydrophobic compound in the granular fertilizer coated with the hydrophobic compound is usually 0.03 to 0.30 parts by weight based on 100 parts by weight of the granular fertilizer.
The granular fertilizer coated with the hydrophobic compound is, for example, a granular fertilizer in a rolling state, a softening or melting temperature at which the hydrophobic compound can be uniformly coated, a hydrophobic compound is added, and the hydrophobic compound is uniformly dispersed and coated. The granular fertilizer can be manufactured by coating the surface of the granular fertilizer with the hydrophobic compound while maintaining the rolling state and the temperature condition until the state is reached.
In addition, the temperature condition at the time of the above production is higher than the softening or melting temperature of the hydrophobic compound, but is preferably lower than the temperature at which the granular fertilizer is liable to be decomposed or deteriorated.

Examples of the iron oxide in the present invention include diiron trioxide (brown iron oxide), ferric oxide (red iron oxide), triiron tetroxide (iron black) and yellow iron oxide, and these may be used alone or in combination of two or more. Can be used in combination.
In order to form a coating layer on the granular fertilizer or the hydrophobic compound-coated granular fertilizer, iron oxide is used in the form of fine powder (usually, particle size (biaxial average diameter) of 0.1 to 5.0 μm).
In the coated granular fertilizer of the present invention, the amount of iron oxide is usually 0.01 to 0.50 parts by weight based on 100 parts by weight of the granular fertilizer.

  Examples of the thermosetting resin in the present invention include urethane resin, epoxy resin, alkyd resin, unsaturated polyester resin, phenol resin, urea resin, melamine resin, urea resin, silicone resin and the like.

Epoxy resin, the reaction of phenols or alcohols and epichlorohydrin in the presence of a curing agent, the reaction of carboxylic acids and epichlorohydrin in the presence of a curing agent, amines in the presence of a curing agent, cyanuric acid or It is formed by the reaction of hydantoin with epichlorohydrin, the reaction of an aliphatic cyclic epoxy compound in the presence of a curing agent, and the like.

  Examples of the curing agent include diethylenetriamine, triethylenetetramine, metaxylylenediamine, isophoronediamine, 1,3-bisaminomethylcyclohexane, diaminodiphenylmethane, 1,3-bisaminomethylcyclohexane, diaminodiphenylmethane, m-phenylenediamine, Diaminodiphenylsulfone, disisisandiamide, organic acid dihydrazide, polyamide-modified polyamine, ketone-modified polyamine, epoxy-modified polyamine, thiourea-modified polyamine, Mannich-modified polyamine, Michael addition-modified polyamine, dodecenyl succinic anhydride, polyazeline anhydride, hexahydrophthalic anhydride Acid, methyltetrahydrophthalic anhydride, methylnadic anhydride, trimetic anhydride, pyromellitic anhydride, benzophenone Tracarboxylic acid, tetrabromophthalic anhydride, heptonic anhydride, novolak-type polyphenol, polymercaptan, polyisocyanate, carboxylic acid-containing polyester resin, benzyldimethylaniline, 2,4,6-trisdimethylaminomethylphenol, 2-methylimidazole, Examples thereof include 2-ethyl, 4-methyl-imidazole, 2-heptadecyl imidazole, aromatic sulfonium salts, aromatic diazonium salts, resole type phenol resins, methylol group-containing urea resins, and methylol group-containing melamine resins.

  Epoxy resins to be produced include bisphenol A type, bisphenol F type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol S type, bisphenol AF type, biphenyl type, naphthalene type, fluorin type, phenol novolak type, and ortho Glycidyl ether type epoxy resin such as cresol novolak type, DPP novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, tetraglycidyldiaminodiphenylmethane type, triglycidylisocyanurate type, hydantoin type, aminophenol type, aniline type, toluidine Glycidylamine type epoxy resin such as a mold, glycidylamine type epoxy resin, alicyclic type epoxy resin and the like.

  The alkyd resin is formed by a reaction between a polybasic acid and a polyhydric alcohol, if necessary, in the presence of a denaturing agent such as a natural vegetable oil or animal fat, a metal soap, or a skin tonic. Examples of the polybasic acid include phthalic anhydride and maleic anhydride, and examples of the polyhydric alcohol include pentaerythol and glycerin. Examples of the denaturing agent include soybean oil, linseed oil, tung oil, safflower oil, coconut oil, palm oil, dehydrated castor oil and the like, and the metal soap is usually manganese, cobalt, zirconium, nickel, Examples include naphthenes such as iron and lead or octylic acids such as zirconium octylate, manganese naphthenate, cobalt octylate, and the like, and mixtures thereof. Examples of the anti-skinning agent include dipentene, methoxyphenol, cyclohexanone oxime, methyl ethyl ketone oxime and the like, or a mixture thereof.

  The unsaturated polyester resin is formed by reacting an unsaturated dibasic acid and a dihydric alcohol in the presence of a vinyl monomer. Examples of the unsaturated dibasic acid include phthalic anhydride, isophthalic acid, terephthalic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrabromophthalic anhydride, tetrachlorophthalic anhydride. Acid, heptonic anhydride, endmethylenetetrahydrophthalic anhydride, and the like. Examples of the dihydric alcohol include ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,6-hexanediol, diethylene glycol, dipropylene glycol, Neopentyl glycol, triethylene glycol, hydrogenated bisphenol A, bisphenol dihydroxypropyl ether and the like can be mentioned. Examples of the vinyl monomer include styrene, vinyl toluene, chlorostyrene, diallyl phthalate, triallyl cyanurate, methyl methacrylate and the like.

  A phenol resin is formed by reacting a phenol with an aldehyde in the presence of a catalyst such as hydrochloric acid, oxalic acid, and hexamethylenetetramine. Examples of the phenols include phenol, o-cresol, m-cresol, p-cresol, xylenol, p-tert-butylphenol, resorcinol and the like. In this reaction, a novolak-type phenol resin is obtained under an acidic catalyst, and a resol-type phenol resin is obtained under a basic catalyst.

The urea resin is formed by a reaction between urea and formalin in the presence of a basic catalyst.
Melamine resin is formed by the reaction of melamine and formalin in the presence of a basic catalyst.
Silicone resin is formed by the reaction of silicone with a polyfunctional siloxane in the presence of a catalyst.

  The urethane resin is formed by three-dimensionally cross-linking by a reaction between a polyisocyanate compound and a polyol compound. Further, two or more kinds of polyisocyanate compounds and / or two or more kinds of polyol compounds may be mixed and used.

  Examples of the polyisocyanate compound include toluene diisocyanate (hereinafter sometimes abbreviated as TDI), diphenylmethane diisocyanate (sometimes abbreviated as MDI), naphthalene diisocyanate, tolidine isocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, and the like. And mixtures thereof can be used as necessary. Among them, MDI, TDI or oligomers derived therefrom (polymeric MDI, polymeric TDI, etc.) are preferably used.

  As the polyol compound, for example, an amino alcohol, an amine or the like is used as an initiator, and propylene glycol, a polyether polyol obtained by polyaddition of an ethylene oxide or propylene oxide with an aliphatic alcohol such as trimethylolpropane, and tetrahydrofuran are polymerized. Polyether polyols such as polytetramethylene ether glycol, natural oils and fats having hydroxyl groups such as isano oil and castor oil, and polyhydric alcohols, and reacting the polyether polyol with a carboxylic acid compound. And the like.

The equivalent ratio of the NCO group derived from the polyisocyanate compound used and the OH group derived from the polyol compound, that is, the so-called NCO / OH, is usually adjusted between 0.9 and 1.2.
In the present invention, the uncured urethane resin which is a urethane resin raw material is a mixture of the polyisocyanate compound and the polyol compound, not only those in which both have not reacted at all, but also a part in advance so as not to be three-dimensional. Also means those that have reacted. The form of the uncured urethane resin may be any of a solvent-free type substantially containing no solvent, a solution type in which a polyol compound and a polyisocyanate compound are dissolved in a solvent, and in particular, a solvent-free type, and a liquid at a processing temperature. Some are preferred.

  It is also a useful technique to add a catalyst to the thermosetting resin material for the purpose of accelerating the curing of the thermosetting resin material, and to perform curing in the presence of the catalyst. can do.

  For example, as the catalyst in the urethane resin, specifically, triethylenediamine, N-methylmorpholine, N, N-dimethylmorpholine, diazabicycloundecene, imidazole, ethylmethylimidazole, diazabicyclooctane, 2,4,4 Amine catalysts such as 6, -tris (dimethylaminomethyl) phenol; ammonia derivatives such as urea; alkaline compounds such as sodium hydroxide and potassium hydroxide; and organic tin compounds such as dibutyltin laurate and dibutyltin malate. Can be Among them, amine catalysts are preferably used. The catalyst is used as it is or as an aqueous solution or suspension. As for the solid catalyst, it is preferable to use one that is pulverized and pulverized.

  When a catalyst is used, the amount of the catalyst is usually about 0.05 to 5% by weight based on the total weight of the polyisocyanate compound and the polyol compound.

  In the coated granular fertilizer of the present invention, the amount of the thermosetting resin is usually 6 to 16 parts by weight based on 100 parts by weight of the granular fertilizer.

  In the coated granular fertilizer of the present invention, the first coating layer made of iron oxide and the second coating layer made of a thermosetting resin, which is adjacent to the outside of the first coating layer made of iron oxide, form a set. Or two or more sets may exist.

  In the coated granular fertilizer of the present invention, there is only one set of a first coating layer made of iron oxide and a second coating layer made of a thermosetting resin adjacent to the outside of the first coating layer made of iron oxide. In this case, the coated granular fertilizer of the present invention is a coated granular fertilizer in which the granular fertilizer is coated in this order from the inside with an iron oxide layer and a thermosetting resin layer.

The coated granular fertilizer of the present invention comprises, for example, (A) adding finely powdered iron oxide to the granular fertilizer in a rolling state, maintaining the rolling state until the fertilizer is uniformly dispersed and coated; Obtaining a coating,
(B) After adding a liquid uncured thermosetting resin to the iron oxide coating in a rolling state, coating the surface of the iron oxide coating with the uncured thermosetting resin while maintaining the rolling state. Then, a step of thermosetting the uncured thermosetting resin to obtain a thermosetting resin coating,
(C) Further, if necessary, using the thermosetting resin composition obtained in the step (B) instead of the granular fertilizer or the hydrophobic compound-coated granular fertilizer, the steps (A) and (B) Repeating one or more times,
Can be manufactured.

  As a specific method of the step of obtaining the iron oxide coating, for example, finely powdered iron oxide having an iron oxide layer thickness of 0.1 to 2.0 μm is added to a rolling fertilizer. A method of adding and mixing, maintaining the rolling state for a predetermined time, and coating the surface of the granular fertilizer or the hydrophobic compound-coated granular fertilizer with the finely powdered iron oxide.

The step of obtaining the thermosetting resin coating is performed by adding a liquid uncured thermosetting resin to the iron oxide coating in a rolling state in such an amount that the thickness of the thermosetting resin layer becomes 1 to 10 μm. A method in which the surface of the iron oxide coating is mixed with the uncured thermosetting resin while maintaining the rolling state for a predetermined time, and then thermosetting is performed.
Here, the curing in the thermosetting does not necessarily need to be a complete curing in general, but means a state in which the thermosetting resin material has passed the gel point and has lost spinnability.
Examples of the method for adding the thermosetting resin raw material include dropping and spraying. The temperature at which the thermosetting resin layer is formed is a temperature at which the gel time of the thermosetting resin material (measured according to JIS K 5909) is usually within 5 minutes, preferably within 3 minutes. When a catalyst is contained in the gel time, the gel time range can be maintained without changing the temperature by adjusting the amount of the catalyst.
When adding the thermosetting resin raw material, a thermosetting resin raw material containing a catalyst can be used, or the thermosetting resin raw material and the catalyst can be separately added. .

  In addition, in the step of obtaining a thermosetting resin coating, a series of steps can be performed once for addition, coating, and thermosetting of the uncured thermosetting resin. It is preferable to divide the series of steps of the addition, coating, and thermosetting into a plurality of times to obtain a desired thermosetting resin layer thickness in order to form a uniform thermosetting resin layer.

  The surface of the coated granular fertilizer of the present invention can further hold an inorganic fine powder and / or a surfactant.

  The coated granular fertilizer of the present invention can be used in paddy fields and also in fields. The application rate varies depending on the target plant, fertilization time, and the like, but is usually 10 to 60 kg per 10 ares. The application is performed by a method usually used when applying fertilizer to agricultural land or non-agricultural land, that is, a method in which the fertilizer is sprayed using an agricultural machine such as a granulator, or a method in which the fertilizer is directly sprayed by hand.

  Hereinafter, the present invention will be described in more detail with reference to Production Examples and Test Examples, but the present invention is not limited to these Examples.

Production Example 1
5 kg of granular urea (average particle size: 3.1 mm) was charged into a rolling type coating device capable of controlling the temperature. The rotating section of the coating apparatus was rotated at 20 to 30 rpm to bring the charged granular urea into a rolling state. After heating the temperature of the granular urea to 70 ° C., ferric oxide [manufactured by Toda Kogyo Co., Ltd., trade name: 120ED, specific gravity: 4.9 to 5.2, average particle size 0.1 to 2. 0 μm, 7.5 g] and tumbled for 3 minutes.
Subsequently, here, polymeric MDI [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumidur 44V10, weight percentage of NCO group in the molecule: 31%, 9.66 g] as a polyisocyanate compound, and a branched polyether as a polyol component Polyol [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen TM, hydroxyl value 372 mg / g, 8.34 g; Sumika Bayer Urethane Co., Ltd., trade name: Sumifen 1600 U, hydroxyl value 115 mg / g, 4.07 g] And castor oil [manufactured by Toyokuni Oil Co., Ltd., trade name: industrial No. 1 castor oil, hydroxyl value 161 mg / g, 2.5 g], and 0.43 g of 2,4,6-tris (dimethylaminomethyl) phenol as a catalyst component. Add the uncured urethane resin composition obtained by mixing, and roll for 3 minutes. It was.
Subsequently, an operation of adding an uncured urethane resin composition having the same composition as described above and rolling for 3 minutes was repeated 15 times, and an uncured urethane resin composition having the same composition as described above was added. Rolled for 3 minutes at ° C.
Here, cut clay [manufactured by Showa Mining Co., Ltd., trade name: special snow cut clay, 4.0 g] and finely powdered sodium lauryl sulfate [manufactured by Kao Corporation, trade name: emal 10 powder, 1.0 g] are added. And rolled for 3 minutes to obtain a coated granular fertilizer of the present invention.

Production Example 2
5 kg of granular urea (average particle size: 3.1 mm) was charged into a rolling type coating device capable of controlling the temperature. The rotating section of the coating apparatus was rotated at 20 to 30 rpm to bring the charged granular urea into a rolling state. After heating the temperature of the granular urea to 70 ° C., microcrystalline wax [manufactured by Nippon Seiro Co., Ltd., trade name: microcrystalline wax HI-MIC-1045, melting point 70 ° C., 5.0 g] was added. Rolled for 10 minutes.
Next, ferric oxide [manufactured by Toda Kogyo Co., Ltd., trade name: 120ED, specific gravity: 4.9 to 5.2, average particle size 0.1 to 2.0 µm, 7.5 g] was added thereto, and 3 g Rolled for minutes.
Subsequently, here, polymeric MDI [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumidur 44V10, weight percentage of NCO group in the molecule: 31%, 9.66 g] as a polyisocyanate compound, and a branched polyether as a polyol component Polyol [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen TM, hydroxyl value 372 mg / g, 8.34 g; Sumika Bayer Urethane Co., Ltd., trade name: Sumifen 1600 U, hydroxyl value 115 mg / g, 4.07 g] And castor oil [manufactured by Toyokuni Oil Co., Ltd., trade name: industrial No. 1 castor oil, hydroxyl value 161 mg / g, 2.5 g], and 0.43 g of 2,4,6-tris (dimethylaminomethyl) phenol as a catalyst component. Add the uncured urethane resin composition obtained by mixing, and roll for 3 minutes. It was.
Subsequently, an operation of adding an uncured urethane resin composition having the same composition as described above and rolling for 3 minutes was repeated 15 times, and an uncured urethane resin composition having the same composition as described above was added. Rolled for 3 minutes at ° C.
Here, cut clay [manufactured by Showa Mining Co., Ltd., trade name: special snow cut clay, 4.0 g] and finely powdered sodium lauryl sulfate [manufactured by Kao Corporation, trade name: emal 10 powder, 1.0 g] are added. And rolled for 3 minutes to obtain a coated granular fertilizer of the present invention.

Production Example 3
Coating of the present invention in the same manner as in Production Example 2 except that the amount of microcrystalline wax [manufactured by Nippon Seiro Co., Ltd., trade name: microcrystalline wax HI-MIC-1045, melting point 70 ° C] was changed to 7.5 g. A granular fertilizer was obtained.

Production Example 4
5 kg of granular urea (average particle size: 3.1 mm) was charged into a rolling type coating device capable of controlling the temperature. The rotating section of the coating apparatus was rotated at 20 to 30 rpm to bring the charged granular urea into a rolling state. After heating the temperature of the granular urea to 70 ° C., as a polyisocyanate compound, polymeric MDI [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumidur 44V10, weight percentage of NCO groups in the molecule: 31%, 9.66 g], a branched polyether polyol as a polyol component [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen TM, hydroxyl value 372 mg / g, 8.34 g, and Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen 1600U] , Hydroxyl value 115 mg / g, 4.07 g] and castor oil [manufactured by Toyokuni Oil Co., Ltd., trade name: industrial castor oil, hydroxyl value 161 mg / g, 2.5 g], and 2,4,6- as a catalyst component Uncured urethane obtained by mixing 0.43 g of tris (dimethylaminomethyl) phenol Was added fat composition was tumbled for 3 minutes.
Next, an operation of adding an uncured urethane resin composition having the same composition as described above and rolling for 3 minutes was repeated 13 times.
Subsequently, ferric oxide [produced by Toda Kogyo Co., Ltd., trade name: 120ED, specific gravity: 4.9 to 5.2, average particle size 0.1 to 2.0 µm, 2.5 g] was added and tumbled for 2 minutes. After that, the operation of adding the uncured urethane resin composition and rolling for 3 minutes was repeated twice.
Further, ferric oxide [manufactured by Toda Kogyo Co., Ltd., trade name: 120ED, specific gravity: 4.9 to 5.2, average particle size 0.1 to 2.0 μm, 2.5 g] was added and tumbled for 2 minutes. After that, the uncured urethane resin composition was added, and tumbled at 74 ° C. for 3 minutes.
Here, cut clay [manufactured by Showa Mining Co., Ltd., trade name: special snow cut clay, 4.0 g] and finely powdered sodium lauryl sulfate [manufactured by Kao Corporation, trade name: emal 10 powder, 1.0 g] are added. And rolled for 3 minutes to obtain a coated granular fertilizer of the present invention.

Production Example 5
5 kg of granular urea (average particle size: 3.1 mm) was charged into a rolling type coating device capable of controlling the temperature. The rotating section of the coating apparatus was rotated at 20 to 30 rpm to bring the charged granular urea into a rolling state. After heating the temperature of the granular urea to 70 ° C., as a polyisocyanate compound, polymeric MDI [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumidur 44V10, weight percentage of NCO groups in the molecule: 31%, 10.77 g], a branched polyether polyol as a polyol component [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen TM, hydroxyl value 372 mg / g, 10.63 g and Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen 1600U] , Hydroxyl value 115 mg / g, 0.69 g) and castor oil [manufactured by Toyokuni Oil Co., Ltd., trade name: industrial castor oil, hydroxyl value 161 mg / g, 2.49 g], and 2,4,6- as a catalyst component Uncured urea obtained by mixing 0.43 g of tris (dimethylaminomethyl) phenol The urethane resin composition was added and tumbled for 3 minutes. Next, an operation of adding an uncured urethane resin composition having the same composition as described above and rolling for 3 minutes was repeated 13 times.
Subsequently, ferric oxide [produced by Toda Kogyo Co., Ltd., trade name: 120ED, specific gravity: 4.9 to 5.2, average particle size 0.1 to 2.0 µm, 2.5 g] was added and tumbled for 2 minutes. After that, the operation of adding the uncured urethane resin composition and rolling for 3 minutes was repeated twice.
Further, ferric oxide [manufactured by Toda Kogyo Co., Ltd., trade name: 120ED, specific gravity: 4.9 to 5.2, average particle size 0.1 to 2.0 μm, 2.5 g] was added and tumbled for 2 minutes. After that, the uncured urethane resin composition was added, and tumbled at 74 ° C. for 3 minutes.
Here, cut clay [manufactured by Showa Mining Co., Ltd., trade name: special snow cut clay, 4.0 g] and finely powdered sodium lauryl sulfate [manufactured by Kao Corporation, trade name: emal 10 powder, 1.0 g] are added. And rolled for 3 minutes to obtain a coated granular fertilizer of the present invention.

Production Example 6
5 kg of granular urea (average particle size: 3.1 mm) was charged into a rolling type coating device capable of controlling the temperature. The rotating section of the coating apparatus was rotated at 20 to 30 rpm to bring the charged granular urea into a rolling state. After heating the temperature of the granular urea to 70 ° C., as a polyisocyanate compound, polymeric MDI [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumidur 44V10, weight percentage of NCO groups in the molecule: 31%, 9.66 g], as a polyol component, a branched polyether polyol [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen TM, hydroxyl value 372 mg / g, 7.46 g] and castor oil [manufactured by Toyokuni Oil Co., Ltd., trade name: industry] No. 1 castor oil, hydroxyl value 161 mg / g, 7.46 g], and 0.43 g of 2,4,6-tris (dimethylaminomethyl) phenol as a catalyst component, to obtain an uncured urethane resin composition. Added and tumbled for 3 minutes. Next, an operation of adding an uncured urethane resin composition having the same composition as described above and rolling for 3 minutes was repeated 13 times.
Subsequently, ferric oxide [produced by Toda Kogyo Co., Ltd., trade name: 120ED, specific gravity: 4.9 to 5.2, average particle size 0.1 to 2.0 µm, 2.5 g] was added and tumbled for 2 minutes. After that, the operation of adding the uncured urethane resin composition and rolling for 3 minutes was repeated twice.
Further, ferric oxide [trade name: 120ED, manufactured by Toda Kogyo Co., Ltd., specific gravity: 4.9 to 5.2, average particle size: 0.1 to 2.0 μm, 2.5 g] was added and tumbled for 2 minutes. After that, the uncured urethane resin composition was added and tumbled at 74 ° C. for 3 minutes.
Here, cut clay [manufactured by Showa Mining Co., Ltd., trade name: special snow cut clay, 4.0 g] and finely powdered sodium lauryl sulfate [manufactured by Kao Corporation, trade name: emal 10 powder, 1.0 g] are added. And rolled for 3 minutes to obtain a coated granular fertilizer of the present invention.

Production Example 7
5 kg of granular urea (average particle size: 3.1 mm) was charged into a rolling type coating device capable of controlling the temperature. The rotating section of the coating apparatus was rotated at 20 to 30 rpm to bring the charged granular urea into a rolling state. After heating the temperature of the granular urea to 70 ° C., microcrystalline wax [manufactured by Nippon Seiro Co., Ltd., trade name: microcrystalline wax HI-MIC-1045, melting point 70 ° C., 7.5 g] was added. Rolled for 10 minutes. Next, ferric oxide [manufactured by Toda Kogyo Co., Ltd., trade name: 120ED, specific gravity: 4.9 to 5.2, average particle size 0.1 to 2.0 µm, 7.5 g] was added thereto, and 3 g Rolled for minutes.
Subsequently, here, polymeric MDI [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumidur 44V10, weight percentage of NCO group in the molecule: 31%, 9.66 g] as a polyisocyanate compound, and a branched polyether as a polyol component Polyol [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen TM, hydroxyl value 372 mg / g, 7.46 g] and castor oil [manufactured by Toyokuni Oil Co., Ltd., trade name: industrial No. 1 castor oil, hydroxyl value 161 mg / g, 7.46 g], and an uncured urethane resin composition obtained by mixing 0.43 g of 2,4,6-tris (dimethylaminomethyl) phenol as a catalyst component, and tumbled for 3 minutes.
Subsequently, an operation of adding an uncured urethane resin composition having the same composition as described above and rolling for 3 minutes was repeated 15 times, and an uncured urethane resin composition having the same composition as described above was added. Rolled for 3 minutes at ° C.
Here, cut clay [manufactured by Showa Mining Co., Ltd., trade name: special snow cut clay, 4.0 g] and finely powdered sodium lauryl sulfate [manufactured by Kao Corporation, trade name: emal 10 powder, 1.0 g] are added. And rolled for 3 minutes to obtain a coated granular fertilizer of the present invention.

Production Example 8
1 kg of granular urea (average particle size: 3.1 mm) was charged into a rolling type coating device capable of controlling the temperature. The rotating section of the coating apparatus was rotated at 20 to 30 rpm to bring the charged granular urea into a rolling state. After heating the temperature of the granular urea to 70 ° C., as a polyisocyanate compound, polymeric MDI [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumidur 44V10, weight percentage of NCO groups in the molecule: 31%, 1.64 g], as a polyol component, a branched polyether polyol [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen TM, hydroxyl value 372 mg / g, 1.49 g] and castor oil [manufactured by Toyokuni Oil Co., Ltd., trade name: industry] No. 1 castor oil, hydroxyl value 161 mg / g, 1.49 g], and 0.09 g of 2,4,6-tris (dimethylaminomethyl) phenol as a catalyst component, to obtain an uncured urethane resin composition. The operation of adding and tumbling at 70 ° C. for 3 minutes (hereinafter referred to as a primary coating operation) was repeated nine times.
Subsequently, ferric oxide [manufactured by Toda Kogyo Co., Ltd., trade name: 120ED, specific gravity: 4.9 to 5.2, average particle size 0.1 to 2.0 μm, 0.5 g] was added, and the mixture was rolled for 3 minutes. Then, an operation of adding an uncured urethane resin composition having the same composition as described above and rolling for 3 minutes was repeated three times.
Here, polyoxyethylene alkyl ether [manufactured by Toho Chemical Co., Ltd., trade name: Pegnol C-18, 0.2 g] and cut clay [manufactured by Showa Mining Co., Ltd., trade name: special snow cut clay, 0.8 g] Added and tumbled for 3 minutes to obtain coated granular fertilizer of the present invention.

Production Example 9
A coated granular fertilizer of the present invention was obtained in the same manner as in Production Example 8 except that the primary coating operation was repeated 11 times.
Production Example 10
A coated granular fertilizer of the present invention was obtained in the same manner as in Production Example 8 except that the primary coating operation was repeated 14 times.
Production Example 11
A coated granular fertilizer of the present invention was obtained in the same manner as in Production Example 8 except that the primary coating operation was repeated 17 times.
Production Example 12
A coated granular fertilizer of the present invention was obtained in the same manner as in Production Example 8 except that the primary coating operation was repeated 21 times.
Production Example 13
A coated granular fertilizer of the present invention was obtained in the same manner as in Production Example 8 except that the primary coating operation was repeated 25 times.

Comparative Production Example 5 kg of granular urea (average particle size: 3.1 mm) was charged into a temperature-controllable rolling type coating apparatus. The rotating section of the coating apparatus was rotated at 20 to 30 rpm to bring the charged granular urea into a rolling state. After heating the temperature of the granular urea to 70 ° C., as a polyisocyanate compound, polymeric MDI [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumidur 44V10, weight percentage of NCO groups in the molecule: 31%, 9.66 g], a branched polyether polyol as a polyol component [manufactured by Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen TM, hydroxyl value 372 mg / g, 8.34 g, and Sumika Bayer Urethane Co., Ltd., trade name: Sumiphen 1600U] , Hydroxyl value 115 mg / g, 4.07 g] and castor oil [manufactured by Toyokuni Oil Co., Ltd., trade name: industrial castor oil, hydroxyl value 161 mg / g, 2.5 g], and 2,4,6- as a catalyst component Uncured urethane obtained by mixing 0.43 g of tris (dimethylaminomethyl) phenol Was added fat composition was tumbled for 3 minutes.
Subsequently, an operation of adding an uncured urethane resin composition having the same composition as described above and rolling for 3 minutes was repeated 15 times, and an uncured urethane resin composition having the same composition as described above was added. Rolled for 3 minutes at ° C.
Here, cut clay [manufactured by Showa Mining Co., Ltd., trade name: special snow cut clay, 4.0 g] and finely powdered sodium lauryl sulfate [manufactured by Kao Corporation, trade name: emal 10 powder, 1.0 g] are added. And rolled for 3 minutes to obtain a coated granular fertilizer.

Test example 1
7.5 g of the coated granular fertilizer for testing was placed in a sample bottle, 100 ml of water was added, and the mixture was allowed to stand at 25 ° C. After a predetermined time, 0.5 ml of water in the sample bottle was taken, and the urea concentration was measured. The urea elution rate was calculated from the measured urea concentration.
Table 1 shows the results.

Test example 2
The operation of putting the coated granular fertilizer for testing into water and eluting the fertilizer component was repeated by exchanging water until the fertilizer component was not eluted in the water. Thereafter, the shell of the coated granular fertilizer from which the fertilizer component was no longer eluted was left at 40 ° C. for 10 days and dried. 100 shells of the test coated granular fertilizer thus obtained were taken, added to 100 ml of water at 25 ° C., and stirred. After allowing this to stand for 1 hour, the state of the shell of the coated granular fertilizer for test was visually observed, and the number of shells of the coated granular fertilizer for test floating in water was counted.
Table 2 shows the results.

  INDUSTRIAL APPLICABILITY The coated granular fertilizer of the present invention is useful for fertilizing a paddy field since the shell of the coating material after elution of the fertilizer component is unlikely to float on the water surface.

Claims (4)

  A coated granular fertilizer having an inner core made of a granular fertilizer, a first coating layer made of iron oxide, and a second coating layer made of a thermosetting resin adjacent to the outside of the first coating layer made of iron oxide.   The coated granular fertilizer according to claim 1, wherein the granular fertilizer is granular urea.   The coated granular fertilizer according to claim 1 or 2, wherein the thermosetting resin is a urethane resin. Rolling granular fertilizer, adding fine powdered iron oxide, uniformly dispersed, maintaining the rolling state until the coated state, to obtain an iron oxide coating of the granular fertilizer, and the rolling state After adding a liquid uncured thermosetting resin to the iron oxide coating, the surface of the iron oxide coating is coated with the uncured thermosetting resin while maintaining the rolling state, and then the uncured thermosetting resin is applied. Obtaining a thermosetting resin coating by thermosetting a thermosetting resin.