Elution control type granule

Abstract

To provide a new agricultural granule which suppresses elution of an agricultural component in water over a long period, and is usable for simultaneous dissemination treatment, and a method capable of efficiently producing the agricultural granule.SOLUTION: A method for producing an elution control type granule includes a first step of mixing (A) saccharin or its salt, and (B) solid paraffin, and obtaining a mixture, and a second step of granulating the mixture, and obtaining a granulated matter, wherein (B) the solid paraffin has a penetration degree according to JIS K 2235-1991 at 25°C of 3 or more and 29 or less.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an elution-controlled granule.

Background Art

[0002] In recent years, with the decrease in the farming population and the aging of the population, there has been an increasing demand for labor-saving in farming operations in crop cultivation management. Conventionally, as a granule treatment technology in the paddy rice field, a large number of insecticides or fungicides and their mixed granules have been commercialized and popularized, mainly by the method of applying them by agricultural workers themselves from 3 days before transplantation to the transplantation day. However, the granule application period in these technologies overlaps with the busy period just before rice transplanting, and the granule application work is a considerable labor burden for agricultural workers, especially those engaged in medium-scale or large-scale farming operations. Therefore, further labor-saving technologies have been eagerly desired.

[0003] Under such circumstances, a rapidly spreading treatment technology in recent years is the simultaneous treatment technology of nursery box granules at the time of sowing. This technology is positioned as a revolutionary control means because the nursery box granules are treated simultaneously during a series of sowing processes.

[0004] On the other hand, in general agricultural granules, the pesticide compound, which is the active ingredient, often elutes from the formulation in a short period, so it is difficult to use them for simultaneous sowing treatment. For simultaneous sowing treatment, elution control of the pesticide component for 30 days or more is required.

[0005] Therefore, methods for manufacturing various agricultural granules with suppressed elution of pesticide active ingredients have been proposed (for example, Patent Documents 1, 2, and 3). Patent Document 1 describes a method for producing an agrochemical granule comprising an agrochemical active ingredient, one type of thermoplastic material, and an inorganic diluent carrier, through (i) a mixing step, (ii) a kneading step, and (iii) an extrusion step, wherein (i) the mixing step and (ii) the kneading step are carried out "under heating conditions", and (iii) the extrusion granulation is carried out at a temperature equal to or higher than the solidification point and lower than the melting point of the thermoplastic material. Specifically, in the examples of this Patent Document 1, it is shown that the kneading step is carried out at a temperature of 76 to 80°C. Further, Patent Document 2 describes a method for producing a coated granular agrochemical composition by solidifying and coating a powdery agrochemical composition with a thermosetting resin. Specifically, in the production example of this Patent Document 2, it is shown that granules are obtained by maintaining the product temperature at 75 ± 5°C. And Patent Document 3 describes a method for producing an agrochemical granule by "heating and kneading" an agrochemical active ingredient, a thermoplastic material, and an inorganic diluent carrier at a temperature equal to or higher than the melting point of the thermoplastic material, cooling, and extruding and granulating the obtained kneaded product at a temperature lower than the melting point of the thermoplastic material. Specifically, in the examples of this Patent Document 3, it is shown that an agrochemical granule is obtained by charging into a Banbury mixer heated to 110°C by a heating device, kneading, and extruding.

[0006] As described above, in the production methods described in these Patent Documents 1 to 3, heating was essential to melt the thermoplastic material or cure the thermosetting resin. For this purpose, a device for maintaining heating at a high temperature, a heating device of a granulator, etc. were required, which was inefficient. Conventionally, when producing an elution control type granule using solid paraffin, there was only a method of producing the granule by heating and melting solid paraffin for coating. And these patent documents do not disclose at all granules that control the elution of an agrochemical component, which is a water-soluble compound having a penetration value of paraffin used as a raw material (Japanese Industrial Standard JIS K2235 - 1991) and exceeding 10 g / 100 g of water solubility.

[0007] And, as a further problem, in recent years, with global warming, abnormal weather, etc., there has been a problem that the water temperature in paddy fields may reach about 40°C. None of Patent Documents 1 to 3 described or suggested anything about the control of elution in water over a long period at a water temperature of 40°C.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0009] An object of the present invention is to provide a novel agrochemical granule in which the elution of an agrochemical component in water is suppressed over a long period and which can be used for simultaneous seeding treatment, and a method capable of efficiently producing the agrochemical granule.

Means for Solving the Problems

[0010] As a result of intensive studies to achieve the above object, the present invention has found that if saccharin or its salt and solid paraffin having a specific penetration are used, mixing and granulation can be carried out without heating, and the obtained granule suppresses the elution of saccharin or its salt, which is an agrochemical component, in water over a long period and can be used for simultaneous seeding treatment. The present invention has been completed based on such findings.

[0011] That is, the present invention is as follows. Item 1. (A) A first step of mixing saccharin or its salt and (B) solid paraffin to obtain a mixture, and A second step of granulating the mixture to obtain granules A method for producing an elution-controlled granule, comprising: The method for producing an elution-controlled granule, wherein the solid paraffin (B) has a penetration of 3 or more and 29 or less according to Japanese Industrial Standard JIS K2235-1991 at 25°C. Item 2. The method for producing an elution-controlled granule according to Item 1, wherein in the first step and the second step, the saccharin (A) or a salt thereof and the solid paraffin (B) are not heated. Item 3. The method for producing an elution-controlled granule according to Item 1, wherein in the first step and the second step, the saccharin (A) or a salt thereof and the solid paraffin (B) are not melted. Item 4. An elution-controlled granule containing (A) saccharin or a salt thereof and (B) solid paraffin, The elution-controlled granule, wherein the solid paraffin (B) has a penetration of 3 or more and 29 or less according to Japanese Industrial Standard JIS K2235-1991 at 25°C. Item 5. The elution-controlled granule according to Item 4, wherein the solid paraffin (B) is contained in an amount of 30 to 50% by mass based on the total mass of the elution-controlled granule. Item 6. The elution-controlled granule according to Item 4, wherein the solid paraffin (B) has a melting point in the range of 48°C to 90°C. Item 7. The elution-controlled granule according to Item 4, wherein the saccharin (A) or a salt thereof is contained in an amount of 4 to 24% by mass based on the total mass of the elution-controlled granule. Item 8. The elution-controlled granule according to Item 4, containing two or more kinds of the solid paraffin (B). Item 9. The elution-controlled granule according to Item 4, wherein the solid paraffin (B) contains a solid paraffin having a melting point of less than 67°C and a solid paraffin having a melting point of 67°C or more. Item 10. The elution-controlled granule according to Item 4, capable of controlling the elution of saccharin or a salt thereof at a water temperature of 40°C.

[0012] In the present invention, for the invention of an article defined in the manufacturing process, since it is impossible or extremely difficult in practice to specify all of what components are included or what its structure is at the present time, it is described by a product-by-process claim.

Advantages of the Invention

[0013] According to the present invention, it is possible to provide a novel elution control type granule in which the elution of saccharin or its salt in water is suppressed over a long period and which can be used for simultaneous seeding treatment. Furthermore, according to the present invention, since solid paraffin having biodegradability is used and a heating step is not required during production, it is possible to provide granules that take environmental considerations into account at low cost. Also, according to the present invention, it is possible to provide a simultaneous seeding treatment granule in which elution into water does not accelerate even when the water temperature rises in summer in paddy fields or the like, and furthermore, the elution rate can be controlled by adding auxiliaries or the like.

Embodiments for Carrying Out the Invention

[0014] <Elution control type granule> The elution control type granule of the present invention is a composition containing saccharin or its salt and solid paraffin (hereinafter sometimes referred to as "the agricultural chemical granule of the present invention" or "the composition of the present invention"). The elution control type granule of the present invention is a granule in which the elution property of the agricultural chemical component is controlled. By forming a matrix with saccharin or its salt and solid paraffin, a granule having sustained release of saccharin or its salt as the agricultural chemical component is obtained. Here, the "matrix" generally refers to a state in which a pesticidal active ingredient is dispersed in a sparingly water-soluble component (base) that is not discontinuous (is a continuous phase). In the elution control type granule of the present invention, solid paraffin forms a continuous phase, and saccharin or a salt thereof is dispersed therein. The elution control type granule of the present invention can control the elution of the pesticidal component (sustained release of the pesticidal component) by forming a matrix. The elution control type granule can also be referred to as a sustained release preparation, an elution control preparation, a matrix type pesticide granule, a matrix pesticide granule, a matrix type pesticide composition, etc.

[0015] Saccharin or its salt Saccharin (1,1-dioxo-1,2-benzothiazol-3-one) is a compound represented by the following formula (1).

[0016]

Chemical formula

[0017] Saccharin or a salt of saccharin is generally used as an artificial sweetener. These are colorless, easily soluble in water, and have a very strong sweet taste. For example, sodium saccharin is a sodium salt of saccharin, and its stability or solubility is improved compared to saccharin. In addition, saccharin or a salt of saccharin is known to have plant resistance induction activity (for example, Japanese Patent Publication No. 2021-523932). The plant resistance induction activity means exerting a disease suppression effect by inducing the resistance of the host plant to diseases (activating the disease control system). For example, the typical disease resistance inducer probenazole (trade name: Orimect (registered trademark)) still plays a very important role in the control of rice blast without causing a resistant bacterium problem even today, more than 30 years after its start of use. A disease resistance inducer usually does not act directly on pathogens, but expresses disease resistance in plants by activating the defense response function. It is considered that there is almost no risk of generating resistant bacteria from its unique mechanism of action. In addition, resistance inducers are attracting attention as next-generation disease control agents with low environmental impact.

[0018] As salts of saccharin, there is no particular limitation as long as they are agriculturally acceptable salts. For example, inorganic acids (e.g., hydrochloride, sulfate, nitrate, etc.), organic acids (e.g., acetate, methanesulfonate, etc.), alkali metal salts (e.g., sodium salt, potassium salt, etc.), alkaline earth metal salts (e.g., calcium salt, etc.), quaternary ammonium salts (e.g., tetramethylammonium salt, tetraethylammonium salt, etc.) and the like can be mentioned. Among them, as salts of saccharin, alkali metal salts are preferred, and sodium salts are more preferred. The saccharin or its salt used in the present invention may be a hydrate or an anhydride. Among them, saccharin or its salt is preferably sodium saccharin and calcium saccharin, and more preferably sodium saccharin. Note that anhydrous means anhydride.

[0019] The content of saccharin or its salt in the elution control type granule is not particularly limited and can be appropriately determined according to the dosage form, application mode, etc. described later. The content of saccharin or its salt is usually 0.01 to 50% by mass, preferably 1 to 40% by mass, more preferably 4 to 24% by mass with respect to 100% by mass of the elution control type granule of the present invention.

[0020] Saccharin or its salt can be said to be a pesticide component with high water solubility. Specifically, the solubility of saccharin or its salt per 100 g of water at 20°C is about 0.2 to 100 g. For example, the water solubility of saccharin at 20°C is 0.2 g / 100 g of water. The water solubility of sodium saccharin at 20°C is 80 g / 100 g of water. The water solubility of sodium saccharin dihydrate at 20°C is 100 g / 100 g of water. The water solubility of calcium saccharinate at 20 °C is 32 g per 100 g of water. The water solubility of calcium saccharinate trihydrate at 20 °C is 37 g per 100 g of water.

[0021] The pesticide (active ingredient) used in the present invention is saccharin or its salt. In addition, known pesticide components, fertilizer components, etc. other than the above saccharin or its salt can be blended in the elution control type granules of the present invention. Details of the pesticide components or fertilizer components will be described later. When a pesticide component or a fertilizer component is blended in the elution control type granules of the present invention, a pesticide component or a fertilizer component having a water solubility at 20 °C lower than 100 g per 100 g of water is considered to be usable.

[0022] Solid paraffin Paraffin is a kind of hydrocarbon compound (organic compound) and is a general term for alkanes (chain saturated hydrocarbons with 20 or more carbon atoms, general formula C n H 2n+2 ). Sometimes it is also called Sekiro in Japanese.

[0023] Paraffin can be roughly classified into two types: solid paraffin and liquid paraffin. Liquid paraffin has many names, such as Nujol, white oil, white mineral oil, water paraffin, mineral oil, mineral oil white, etc. Among them, the most familiar liquid paraffin is baby oil. Liquid paraffin is insoluble in water, colorless liquid at room temperature, and non-volatile liquid. In the UK and South Africa, paraffin oil or simply paraffin may be used to refer to kerosene lamp oil. Note that kerosene is one of the fractional distillation components of petroleum, the main component of lamp oil, etc., with a boiling point of about 150 - 280 °C, 10 - 15 carbon atoms, and a density of 0.79 - 0.83. Kerosene is heavier than naphtha (raw material for gasoline) and lighter than gas oil.

[0024] On the one hand, solid paraffin is a translucent to white, soft solid (wax-like) at room temperature, insoluble in water, and a chemically stable substance. The solid paraffin component is mainly a mixture of normal paraffins with 20 or more carbon atoms, and the melting point varies depending on the application. In Japan, it is often simply called paraffin, but to avoid confusion with kerosene, it is sometimes also called paraffin wax. Solid paraffin is commonly used in, for example, candles, crayons, etc., and is often treated as wax in daily life. Note that chemically, Japanese wax is completely different from Western wax, so it is necessary to pay attention.

[0025] The solid paraffin used in the present invention is not particularly limited. From the perspective of the granulation property of the elution control type granules, the penetration at 25 °C is preferably 3 or more, more preferably 3 - 30, even more preferably 3 - 29, and particularly preferably 10 - 15.

[0026] Penetration is generally a measurement method for determining the hardness of petroleum wax. The measurement method is described in JIS K2235-1991. Specifically, the sample is heated and melted, taken into a container, cooled, and then kept at a constant temperature in a thermostatic bath. A load of 100 g is applied, and it is determined how many millimeters the needle (tip size 0.14 - 0.16 mm) penetrates into the sample in 5 seconds, and the value is represented by 10 times this number.

[0027] The solid paraffin used in the present invention preferably has a melting point in the range of 48 °C to 90 °C. There are no particular limitations on the types of solid paraffin that can be used in the present invention. For example, paraffin wax - 115 (manufactured by Nippon Seiro Co., Ltd., melting point: 48°C, penetration (25°C): 29, molecular weight: about 300 - 550), paraffin wax - 120 (manufactured by Nippon Seiro Co., Ltd., melting point: 50°C, penetration (25°C): 22, molecular weight: about 300 - 550), paraffin wax - 125 (manufactured by Nippon Seiro Co., Ltd., melting point: 53°C, penetration (25°C): 15, molecular weight: about 300 - 550), paraffin wax - 130 (manufactured by Nippon Seiro Co., Ltd., melting point: 56°C, penetration (25°C): 13, molecular weight: about 300 - 550), paraffin wax - 135 (manufactured by Nippon Seiro Co., Ltd., melting point: 59°C, penetration (25°C): 11, molecular weight: about 300 - 550), paraffin wax - 140 (manufactured by Nippon Seiro Co., Ltd., melting point: 61°C, penetration (25°C): 10, molecular weight: about 300 - 550), paraffin wax - 145 (manufactured by Nippon Seiro Co., Ltd., melting point: 63°C, penetration (25°C): 12, molecular weight about 300 - 550), paraffin wax - 150 (manufactured by Nippon Seiro Co., Ltd., melting point: 66°C, penetration (25°C): 12, molecular weight: about 300 - 550), paraffin wax - 155 (manufactured by Nippon Seiro Co., Ltd., melting point: 69°C, penetration (25°C): 12, molecular weight about 300 - 550), microcrystalline wax LUVAX2191 (manufactured by Nippon Seiro Co., Ltd., melting point: 85°C, penetration (25°C): 13, molecular weight: about 500 - 800), FT wax FNP - 0090 (manufactured by Nippon Seiro Co., Ltd., freezing point: 90°C, penetration (25°C): 3, molecular weight about 600 - 1000), etc. can be mentioned.

[0028] The solid paraffin may be used alone or two or more kinds may be appropriately mixed and used. The elution - controlled granules of the present invention preferably contain two or more kinds of solid paraffin. When containing two or more kinds of solid paraffin, it is preferable to contain a solid paraffin with a melting point of less than 67°C and a solid paraffin with a melting point of 67°C or higher. The blending amount of the solid paraffin is not particularly limited. For example, with respect to 100% by mass of the total mass of the elution - controlled granules, it is usually 20 - 80% by mass, preferably 30 - 70% by mass, and more preferably 30 - 50% by mass.

[0029] The elution-controlled granule of the present invention may consist only of saccharin or its salt, which is the above-described active ingredient, and solid paraffin. However, in addition to saccharin or its salt and solid paraffin, various fertilizer components, additives, etc. can be included according to the dosage form, application mode, etc. described later.

[0030] The shape of the elution-controlled granule of the present invention is not particularly limited. Examples of the shape include columnar, spherical, granular, etc., and a columnar shape is preferred. The elution-controlled granule of the present invention preferably has an average particle size of 3.0 mm or less, more preferably 0.5 mm or more and 2.0 mm or less.

[0031] The dosage form of the elution-controlled granule of the present invention is not particularly limited as long as it is an agriculturally acceptable dosage form. Examples include solid agents, tablets, granules, pellets, fine granules, powder granules, jumbo agents, etc. The application rate or application concentration of the elution-controlled granule of the present invention can be changed according to weather conditions, application time, application location, application method, etc. Usually, it is about 0.1 to 300 g / a, preferably about 0.5 to 100 g / a, more preferably about 1 to 50 g / a.

[0032] The present invention includes an elution-controlled granule composition further containing a pesticide component and / or a fertilizer component other than saccharin or its salt in addition to the above elution-controlled granule.

[0033] The pesticide component other than saccharin or its salt is not particularly limited. For example, it can be further mixed or used in combination with one or more selected from other fungicides, insecticides, acaricides, nematicides, herbicides, plant growth regulators, microbial materials, molluscicides, and bird damage inhibitors. The microbial material referred to here is a microorganism having a control effect on pests (e.g., insecticidal activity, acaricidal activity, nematicidal activity, fungicidal activity, herbicidal activity, etc.) and a plant growth regulation effect such as rhizobia and mycorrhizal fungi.

[0034] Insecticides that can be used in the present invention are not particularly limited. For example, BPMC, MEP, PAP, isocycloseram, imidacloprid, ethiprole, etofenprox, oxathiazulf, cartap, carbosulfan, clothianidin, chlorantraniliprole, cyantraniliprole, cycloprothrin, dichloromethothiaz, dinotefuran, silafluofen, spinetoram, spinosad, sulfoxaflor, thiacloprid, thiamethoxam, thiocyclam, tetraniliprole, tebufenozide, triflumizopyrim, pymetrozine, fipronil, buprofezin, flupyradifurone, flupyrimin, benzpyramoxan, bensultap, benfuracarb, fosthiazate, methoxyphenozide, etc. can be mentioned.

[0035] Moreover, fungicides that can be used in the present invention are not particularly limited. For example, IBP, TPN, azoxystrobin, amisulbrom, isopyrazam, isoprothiolane, ipconazole, ipfencarbazone, iminoctadine acetate, impflutrexim, oxolinic acid, kasugamycin, quinoxyfen, cyazofamid, triticonazole, triflumizole, tolprocarb, validamycin, picarbutrazox, hydroxyisoxazole, pyroquilon, ferimzone, fthalide, flutolanil, procymidone, probenazole, benomyl, penthiopyrad, penflufen, metalaxyl-M, metominostrobin, mepronil, copper, etc. can be mentioned.

[0036] In addition, the herbicides that can be used in the present invention are not particularly limited. For example, 2,4-dichlorophenoxyacetate, DCMU, MCPB-E, azimsulfuron, asulam, acetochlor, atrazine, anilophos, amicarbazone, isouron, isoxachlortol, isoxaben, ipfencarbazone, imazakine, imazosulfuron, indanofan, esprocarb, ethoxysulfuron, etobenzanid, oxadiazon, oxadiargyl, oxadiquone, oxyfluorfen, oryzalin, cafenstrole, quizalofop-ethyl, cumyluron, glyphosate salt, glufosinate salt, chlormepropt, cyanazine, cyanamide, diuron, cyclosulfamuron, cyclopyranil, cyclopyrimorate, diquat, cyhalofop-butyl, diphenamid, diflufenican, simazine, dimetamethrin, simetryn, setoxydim, dimefuron, thiobencarb, thifensulfuron-methyl, tenylchlor, tebuthiuron, tefuryltrione, topramezone, triafamone, trifluralin, napropamide, halosulfuron-methyl, biphenox, pyraclonil, pyrazoxyfen, pyrazosulfuron-ethyl, pyrazolate, pyriftalid, pyributicarb, pyrimisulfan, pyriminobac-methyl, pyroxasulfone, fenoxasulfone, fentrazamide, fenquinotrione, fenmedifam, butachlor, butamifos, flazasulfuron, fluazifop-P, flucetosulfuron, flufenacet, flupoxam, flumioxazin, pretilachlor, prosulfocarb, propanil, propyzamide, propyrisulfuron, bromacil, prometryn, bromobutide, hexazinone, penoxsulam, bensulfuron-methyl, benzobicyclone, benzofenap, bentazone, pentachlor, pentoxazone, benfuresate, mecoprop-P potassium salt, mesotrione, metazachlor, metamifop, metribuzin, mefenacet, molinate, linuron, lenacil, etc. can be mentioned.

[0037] The content ratio of the pesticide component other than saccharin or its salt in the elution-controlled granule can be appropriately determined according to the dosage form, application mode, etc. described later. For example, it can be used in an amount of usually 0.1 to 50% by mass, preferably 1 to 40% by mass, more preferably 5 to 30% by mass, based on the elution-controlled granule.

[0038] The fertilizer component is not particularly limited as long as it is an agriculturally acceptable fertilizer component. For example, N, P, K, Ca, Mg, S, B, Fe, Mn, Cu, Zn, Mo, Si, etc., and further inorganic substances (inorganic fertilizers) and organic substances (organic fertilizers) that are sources thereof can be mentioned. Such inorganic substances include ammonium nitrate, potassium nitrate, ammonium sulfate, ammonium chloride, ammonium phosphate, urea, ammonium carbonate, potassium phosphate, potassium phosphite, calcium phosphite, superphosphate of lime, potassium sulfate, potassium chloride, calcium nitrate, slaked lime, calcium carbonate, magnesium sulfate, magnesium hydroxide, magnesium carbonate, magnesium chloride, boric acid, manganese sulfate, manganese chloride, chelated iron, ferric chloride, chelated copper, chelated zinc, ammonium molybdate, etc. In addition, examples of the organic substances include chicken manure, cow manure, bark compost, seaweed, plant extract components, vitamins (vitamin B1, vitamin C, etc.), amino acids (glycine, glutamic acid, sodium glutamate, etc.) and salts thereof.

[0039] The content ratio of the fertilizer component in the elution-controlled granule can be appropriately determined according to the dosage form, application mode, etc. described later. For example, it can be used in an amount of usually 0.1 to 40% by mass, preferably 1 to 30% by mass, more preferably 5 to 20% by mass, based on the elution-controlled granule.

[0040] In addition, additives may be further incorporated into the elution-controlled granule of the present invention. Therefore, the present invention includes an elution-controlled granule composition containing a fertilizer component in addition to the elution-controlled granule. The present invention also includes an elution-controlled granule composition containing a fertilizer component and an additive in addition to the elution-controlled granule.

[0041] The additive is not particularly limited as long as it is an agriculturally acceptable additive. Examples thereof include antioxidants, carriers, surfactants, thickeners, extenders, binders, preservatives, pH adjusters, volatilization inhibitors, precipitation inhibitors, and the like.

[0042] When the elution-controlled granule of the present invention contains the additive, the blending amount can be appropriately adjusted within a range that does not lose the effectiveness of saccharin or its salt.

[0043] It is preferable to blend an extender as an additive in the elution-controlled granule of the present invention. As the extender, any extender or carrier usually used in agricultural chemical granules or granules can be used without particular limitation. Examples of the extender include clay, silica, talc, bentonite, barium sulfate, calcium carbonate, pumice, diatomaceous earth, vermiculite, perlite, attapulgite, amorphous silicon dioxide (commonly known as white carbon), synthetic amorphous silica, and the like. These can be used alone or in combination of two or more.

[0044] Further, a surfactant may be blended as an additive in the elution-controlled granule of the present invention. By using a surfactant together with saccharin or its salt, the sustained-release rate of saccharin or its salt contained in the elution-controlled granule can be finely adjusted.

[0045] As the surfactant, those that are soluble in water, such as nonionic surfactants, cationic surfactants, amphoteric surfactants, and anionic surfactants, can be used.

[0046] Examples of the nonionic surfactant include sorbitan fatty acid esters, polyoxyalkylene sorbitan fatty acid esters, polyoxyalkylene fatty acid esters, glycerin fatty acid esters, polyoxyalkylene glycerin fatty acid esters, polyglycerin fatty acid esters, polyoxyalkylene polyglycerin fatty acid esters, sucrose fatty acid esters, resin acid esters, polyoxyalkylene resin acid esters, polyoxyalkylene alkyl ethers, polyoxyalkylene alkyl phenyl ethers, alkyl(poly)glycosides, polyoxyalkylene alkyl(poly)glycosides, and the like. Preferred examples of the nonionic surfactant include an ether group-containing nonionic surfactant not containing a nitrogen atom and an ester group-containing nonionic surfactant. Particularly preferred examples of the nonionic surfactant include ester group-containing nonionic surfactants containing an oxyalkylene group such as polyoxyalkylene sorbitan fatty acid esters, polyoxyalkylene fatty acid esters, polyoxyalkylene glycerin fatty acid esters, polyoxyalkylene polyglycerin fatty acid esters; ether group-containing nonionic surfactants not containing a nitrogen atom having a sugar skeleton such as alkyl(poly)glycosides, and the like.

[0047] Examples of the anionic surfactant include carboxylic acid surfactants, sulfonic acid surfactants, sulfuric acid ester surfactants, and phosphoric acid ester surfactants. Examples of the carboxylic acid surfactant include fatty acids having 6 to 30 carbon atoms or their salts, polyvalent carboxylate salts, polyoxyalkylene alkyl ether carboxylate salts, polyoxyalkylene alkyl amide ether carboxylate salts, rosin acid salts, dimer acid salts, polymer acid salts, tall oil fatty acid salts, etc. Examples of the sulfonic acid surfactant include alkylbenzene sulfonate salts, alkyl sulfonate salts, alkyl naphthalene sulfonate salts, naphthalene sulfonate salts, diphenyl ether sulfonate salts, condensate salts of alkyl naphthalene sulfonic acid, condensate salts of naphthalene sulfonic acid, etc. Examples of the sulfuric acid ester surfactant include alkyl sulfate ester salts, polyoxyalkylene alkyl sulfate ester salts, polyoxyalkylene alkyl phenyl ether sulfate ester salts, tristyrylphenol sulfate ester salts, polyoxyalkylene distyrylphenol sulfate ester salts, alkyl polyglycoside sulfates, etc. Examples of the phosphoric acid ester surfactant include alkyl phosphoric acid ester salts, alkyl phenyl phosphoric acid ester salts, polyoxyalkylene alkyl phosphoric acid ester salts, polyoxyalkylene alkyl phenyl phosphoric acid ester salts, etc. Examples of the salt include metal salts (such as Na, K, Ca, Mg, Zn, etc.), ammonium salts, alkanolamine salts, aliphatic amine salts, etc. The anionic surfactant is preferably a carboxylic acid surfactant and a phosphoric acid ester surfactant.

[0048] Examples of amphoteric surfactants include amino acid-based surfactants, betaine-based surfactants, imidazoline-based surfactants, amine oxide-based surfactants, etc. Examples of amino acid-based surfactants include acyl amino acid salts, acyl sarcosine salts, acyloyl methyl aminopropionate salts, alkyl aminopropionate salts, acyl amide ethyl hydroxyethyl methyl carboxylate salts, etc. Examples of betaine-based surfactants include alkyl dimethyl betaine, alkyl hydroxyethyl betaine, acyl amide propyl hydroxypropyl ammonium sulfobetaine, acyl amide propyl hydroxypropyl ammonium sulfobetaine, ricinoleic acid amide propyl dimethyl carboxymethyl ammonium betaine, etc. Examples of imidazoline-based surfactants include alkyl carboxymethyl hydroxyethyl imidazolinium betaine, alkyl ethoxy carboxymethyl imidazolinium betaine, etc. Examples of amine oxide-based surfactants include alkyl dimethyl amine oxide, alkyl diethanol amine oxide, alkyl amide propyl amine oxide, etc. The above surfactants may be used alone or in combination of two or more.

[0049] The content ratio of the surfactant in the elution-controlled granules is, for example, usually 0.01 to 10% by mass, preferably 0.1 to 10% by mass, more preferably 0.5 to 5% by mass based on the elution-controlled granules.

[0050] Also, from the viewpoint of sustained release, the mass ratio of saccharin or its salt to the surfactant is preferably 1:0.001 to 1000, more preferably 1:0.01 to 100, and even more preferably 1:0.1 to 10 for saccharin or its salt:surfactant.

[0051] The elution-controlled granules containing saccharin or a salt thereof and solid paraffin of the present invention can be used for treating farmland and non-farmland for sending. As a seed treatment agent, spraying treatment, film coating treatment, spraying and coating, dipping treatment, etc. on seed tubers, etc.; as a foliage treatment agent, spraying treatment, top dressing treatment, etc.; as a soil treatment agent, surface spraying treatment, mixing treatment, perfusion treatment, fumigation treatment, planting hole treatment, stock base treatment, ridging treatment, sowing furrow treatment, seedling box treatment, seedling pot treatment, etc.; as a paddy field treatment agent, granule treatment, jumbo agent treatment, flowable agent treatment, etc.; as other treatment agents, it can be used for fumigation treatment, lawn treatment, etc. Among these treatments, it can be preferably used as a seed treatment agent or a soil treatment agent.

[0052] The target plants of the elution-controlled granules of the present invention are not particularly limited. There is no particular limitation on the useful plants for which the elution-controlled granules of the present invention can be used. For example, Solanaceae such as tomato, eggplant, pepper, capsicum, potato, etc.; Gramineae such as rice, barley, wheat, rye, corn, sugarcane, etc.; Leguminosae such as soybean, adzuki bean, broad bean, pea, kidney bean, peanut, etc.; Rosaceae such as apple, pear, peach, plum, apricot, strawberry, rose, etc.; Brassicaceae such as cabbage, broccoli, Chinese cabbage, radish, turnip, komatsuna, etc.; Cucurbitaceae such as pumpkin, cucumber, wax gourd, watermelon, melon, etc.; Alliaceae such as onion, leek, garlic, chives, etc.; Lamiaceae such as perilla, basil, thyme, lavender, etc.; Chenopodiaceae such as spinach, sugar beet, etc.; Apiaceae such as carrot, parsley, etc.; Asteraceae such as lettuce, burdock, chrysanthemum, etc.; Convolvulaceae such as sweet potato, etc.; in addition, fruit trees such as citrus fruits, grape, chestnut, almond, banana, etc.; root vegetables such as taro, lotus root, etc.; industrial crops such as cotton, hemp, hop, olive, rubber, coffee, tea, etc.; forage grasses such as orchardgrass, sorghum, timothy, clover, alfalfa, etc.; lawn grasses such as Korean lawn grass, bentgrass, etc.; spice ornamental crops such as pepper, ginger, etc.; flower crops such as carnation, orchid, etc.; garden trees such as ginkgo, cherry blossoms, aoki, etc.; forest trees such as firs, Siberian firs, pines, hiba, cedar, cypress, etc.

[0053] Further, the object is not limited to the whole of the above-described plant body, and may be at least one of plant organs such as flowers, leaves, fruits, stems, and roots.

[0054] The application mode of the elution control type granule or the elution control type granule composition of the present invention is not particularly limited as long as it is a mode known (or a mode to be developed in the future) as the use mode of agricultural chemicals or fertilizers. For example, spraying, dripping, coating, mixing or dissolving in the plant growth environment (in soil, water, solid medium, liquid medium, culture solution, etc.) can be mentioned.

[0055] The present invention includes a method for imparting environmental stress tolerance to plants, which uses the above-described elution control type granule or elution control type granule composition for plants or the soil or culture solution in which the plants grow. By using this method, the growth of plants under normal conditions can be promoted inexpensively and simply, and the environmental stress tolerance of plants can be enhanced. Further, the present invention includes the use of saccharin or a salt thereof for imparting plant stress tolerance.

[0056] The auxiliary agent added to achieve the same elution in water at water temperatures of 20°C and 40°C is formulated in an amount of 0.1 to 10% by mass, preferably 1 to 5% by mass, based on the total mass of the agricultural chemical granule. Examples include, but are not limited to, diatomaceous earth (manufactured by Showa Chemical Industry Co., Ltd., trade names: Radiolite 200, Radiolite 500, Radiolite F), bentonite (manufactured by Kunimine Industries Co., Ltd., trade names: Kunigel V1, Kunibis 110, Moistnite WO, Smeton SA), organic bentonite (manufactured by Hoejun Co., Ltd., trade names: Esven, Esven W, Esven N400), synthetic amorphous silica (manufactured by Nippon Aerosil Co., Ltd., trade names: Aerosil 200, Aerosil R805, Aerosil R972).

[0057] Examples of the bulking agent used in the present invention include inorganic clays, calcium stearate, talc, calcium carbonate, iron (II, III) oxide powder, barium sulfate, etc. Among them, barium sulfate with a high specific gravity is particularly preferred. The amount of the bulking agent used in the present invention is such that when saccharin or its salt, a hydrophobic substance, an oil-absorbing material, and the bulking agent are added, the total amount is 100% by mass.

[0058] The elution-controlled granule of the present invention can control the elution of saccharin or its salt having high water solubility. In addition, the elution-controlled granule of the present invention uses biodegradable solid paraffin and does not require a heating step during production, so that granules considering the environment can be provided at low cost. In addition, the elution-controlled granule of the present invention can control the elution of saccharin or its salt at a water temperature of 40°C. Therefore, even when the water temperature rises in summer in paddy fields or the like, the elution of saccharin or its salt into water does not accelerate, and furthermore, it is possible to provide a simultaneous seeding treatment granule capable of controlling the elution rate even at different water temperatures by adding auxiliaries or the like.

[0059] Method for producing elution-controlled granules The method for producing the elution-controlled granule of the present invention is not particularly limited. For example, in the first step, (A) saccharin or its salt and (B) solid paraffin are mixed to obtain a mixture, and a method for producing an elution-controlled granule, comprising a second step of granulating the mixture to obtain a granulated product, wherein the (B) solid paraffin has a penetration according to Japanese Industrial Standard JIS K2235-1991 at 25°C of 3 or more and 29 or less.

[0060] First step (mixing step) The first step is a mixing step of mixing (A) saccharin or a salt thereof and (B) solid paraffin to obtain a mixture. Since it is only necessary to mix the (A) saccharin or a salt thereof and the (B) solid paraffin to obtain a powdery or granular mixture, there is no need to heat. Therefore, in the first step, it is preferable to mix (A) saccharin or a salt thereof and (B) solid paraffin without heating. Since the first step is carried out without heating, the (A) saccharin or a salt thereof and the (B) solid paraffin are not melted.

[0061] Second step (granulation step) The second step is a granulation step of granulating the mixture obtained in the first step to obtain granules. The powdery or granular mixture obtained in the first step is put into a granulator and extrusion granulated. The granulator used in the present invention is not particularly limited, but a screw type forward extrusion granulator or a screw type lateral extrusion granulator that is more likely to generate heat during granulation is preferable to a basket type granulator.

[0062] Also in this granulation step, it is preferably not intentionally heated. Even without heating, in the extrusion granulator, heat is generated by frictional heat to soften the solid paraffin, and a kneaded product can be formed with saccharin or a salt thereof, and it is extrusion granulated. Therefore, at this stage, it is not necessary to add water like a normal kneaded granule. Also, since the second step is carried out without heating, the (A) saccharin or a salt thereof and the (B) solid paraffin are not melted. By granulating using a die having a predetermined pore diameter in advance, it is formed into granules having a predetermined particle size.

[0063] The extruded granules are then, if necessary, subjected to a cooling process, a granulation process, etc., to obtain the elution-controlled granules. In the production method of the present invention, since no water is added in the extrusion granulation process, the obtained granules do not require a drying process. The cooling process is not particularly limited as long as the obtained granules are cooled to about room temperature. Examples of the cooling method include natural cooling. The granulation process is, for example, a process of crushing with a crusher equipped with a screen corresponding to the desired particle size, and may include a screening process if necessary.

[0064] In the production method of the elution-controlled granules of the present invention, in the first step and the second step, it is preferable not to heat the (A) saccharin or its salt and the (B) solid paraffin. Further, in the production method of the elution-controlled granules of the present invention, in the first step and the second step, it is preferable that the (A) saccharin or its salt and the (B) solid paraffin are not melted.

Examples

[0065] Hereinafter, the elution-controlled granules of the present invention will be specifically described, but the technical scope of the present invention is not limited to these examples.

[0066] Example 1 10% by mass of anhydrous sodium saccharin (manufactured by Daiwa Kasei Co., Ltd., melting point about 230°C), 30% by mass of solid paraffin (trade name: Paraffin Wax - 155, penetration 12, melting point 69°C, manufactured by Nippon Seiro Co., Ltd.), and 56% by mass of barium sulfate (trade name: Barite, manufactured by Takehara Chemical Industry Co., Ltd.) were mixed. This mixture was granulated with an extrusion granulator (Dome Gran DG-L1 type, extrusion particle diameter 1.2 mm, manufactured by Dalton Co., Ltd.), sieved with a sieve (JIS Z8801-1-2019; mesh opening 2000 μm, wire diameter 760 μm) to obtain elution-controlled granules. Then, 4% by mass of barium sulfate was coated on the surface of the obtained elution-controlled granules to prevent caking. Although not intentionally heated in the mixing and granulation processes, the granules were warm during granulation. When the temperature of the granules was measured using a non-contact thermometer (manufactured by Custom Co., Ltd., product name: Radiation Thermometer IR-210) during granulation, it was 47°C. Despite not being actively heated, the temperature of the granules increased because the mixture generated heat due to friction with the extrusion granulator during granulation. Since the temperature of the granules was below the melting points of sodium saccharin anhydrous and solid paraffin, sodium saccharin anhydrous and solid paraffin were not melted.

[0067] Example 2 Granulation and sieving were carried out in the same manner as in Example 1, except that 56% by mass of barium sulfate in Example 1 was replaced with 51% by mass of barium sulfate and 5% by mass of diatomaceous earth (trade name: Radiolite 200, manufactured by Showa Chemical Industry Co., Ltd.) to obtain elution-controlled granules. Similar to Example 1, when the temperature of the granules was measured using a non-contact thermometer (manufactured by Custom Co., Ltd., product name: IR-210) during granulation, it was 52°C. Example 2 is described as an example in which the elution amounts of the agrochemical active ingredient into water at a water temperature of 20°C and a water temperature of 40°C can be adjusted to be approximately the same.

[0068] Example 3 4% by mass of sodium saccharin anhydrous (manufactured by Daiwa Kasei Co., Ltd.), 40% by mass of solid paraffin (trade name: Paraffin Wax-115, penetration 29, melting point 48°C, manufactured by Nippon Seiro Co., Ltd.), and 52% by mass of barium sulfate (trade name: Barite, manufactured by Takehara Chemical Industry Co., Ltd.) were mixed. This mixture was granulated and sieved in the same manner as in Example 1 to obtain elution-controlled granules. Then, 4% by mass of barium sulfate was used to coat the surface of the obtained elution-controlled granules. Similar to Example 1, when the temperature of the granules was measured using a non-contact thermometer (manufactured by Custom Co., Ltd., product name: IR-210) during granulation, it was 44°C.

[0069] Example 4 24% by mass of anhydrous sodium saccharin (manufactured by Yamato Kasei Co., Ltd.), 35% by mass of solid paraffin (trade name: Paraffin Wax - 140, penetration 10, melting point 61°C, manufactured by Nippon Seiro Co., Ltd.), 5% by mass of synthetic amorphous silica (trade name: AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.), and 32% by mass of barium sulfate (trade name: Barite, manufactured by Takehara Chemical Industry Co., Ltd.) were mixed. This mixture was granulated and sieved in the same manner as in Example 1 to obtain an elution - controlled granule. Then, 4% by mass of barium sulfate was used for film - coating on the surface of the obtained elution - controlled granule. Note that, in the same manner as in Example 1, when the temperature of the granule was measured using a non - contact thermometer (manufactured by Custom Co., Ltd., product name: IR - 210) during granulation, it was 50°C.

[0070] Example 5 24% by mass of anhydrous sodium saccharin (manufactured by Yamato Kasei Co., Ltd.), 30% by mass of solid paraffin (trade name: FNP - 0900, penetration 3, melting point 90°C, manufactured by Nippon Seiro Co., Ltd.), 20% by mass of solid paraffin (trade name: Paraffin Wax 140, penetration 10, melting point 61°C, manufactured by Nippon Seiro Co., Ltd.), and 22% by mass of barium sulfate (trade name: Barite, manufactured by Takehara Chemical Industry Co., Ltd.) were mixed. This mixture was granulated and sieved in the same manner as in Example 1 to obtain an elution - controlled granule. Then, 4% by mass of barium sulfate was used for film - coating on the surface of the obtained elution - controlled granule. Note that, in the same manner as in Example 1, when the temperature of the granule was measured using a non - contact thermometer (manufactured by Custom Co., Ltd., product name: IR - 210) during granulation, it was 53°C.

[0071] Example 6 10% by mass of saccharin (manufactured by Tokyo Chemical Industry Co., Ltd.), 30% by mass of solid paraffin (trade name: Paraffin Wax - 155, penetration 12, melting point 69°C, manufactured by Nippon Seiro Co., Ltd.), and 56% by mass of barium sulfate (trade name: Barite, manufactured by Takehara Chemical Industry Co., Ltd.) were mixed. This mixture was granulated and sieved in the same manner as in Example 1 to obtain an elution - controlled granule. Then, 4% by mass of barium sulfate was used for film - coating on the surface of the obtained elution - controlled granule. Note that, in the same manner as in Example 1, when the temperature of the granule was measured using a non - contact thermometer (manufactured by Custom Co., Ltd., product name: IR - 210) during granulation, it was 48°C.

[0072] Example 7 12% by mass of sodium saccharin dihydrate (manufactured by Tokyo Chemical Industry Co., Ltd.), 40% by mass of solid paraffin (trade name: Paraffin Wax - 155, penetration 12, melting point 69°C, manufactured by Nippon Seiro Co., Ltd.), and 44% by mass of barium sulfate (trade name: Barite, manufactured by Takehara Chemical Industry Co., Ltd.) were mixed. This mixture was granulated and sieved in the same manner as in Example 1 to obtain an elution - controlled granule. Then, 4% by mass of barium sulfate was coated on the surface of the obtained elution - controlled granule. Note that, as in Example 1, when the temperature of the granule was measured using a non - contact thermometer (manufactured by Custom Co., Ltd., product name: IR - 210) during granulation, it was 48°C.

[0073] Comparative Example 1 24% by mass of anhydrous sodium saccharin, 0.2% by mass of sodium lauryl sulfate (New Calgen LX - C, manufactured by Takemoto Yushi Co., Ltd.), 5% by mass of polyvinyl alcohol (trade name: JP - 05S, manufactured by Nippon Vinyl Acetate - Poval Co., Ltd.), and 70.8% by mass of barium sulfate (trade name: Barite, manufactured by Takehara Chemical Industry Co., Ltd.) were mixed, and then an appropriate amount of water was added and kneaded. The obtained kneaded product was granulated using an extrusion granulator (Dome Gran DG - L1 type, extrusion particle diameter 1.2 mm, manufactured by Dalton Co., Ltd.), dried using a fluidized - bed dryer, and then the dried product was sieved with a sieve (JIS Z8801 - 1 - 2019; aperture 2000 μm, wire diameter 760 μm) to obtain Comparative Granule 1.

[0074] Comparative Example 2 25% by mass (8% by mass as solid content) of an aqueous synthetic polyurethane resin emulsion (trade name: Superflex 420, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., 32%) was sprayed onto 92% by mass of the granules obtained in Comparative Example 1, and then dried using a fluidized - bed dryer. The obtained dried product was sieved with a sieve (JIS Z8801 - 1 - 2019; aperture 2000 μm, wire diameter 760 μm) to obtain Comparative Granule 2 (coated preparation).

[0075] Comparative Example 3 After heating 90% by mass of the granules obtained in Comparative Example 1 to 70°C, 10% by mass of separately heated and melted solid paraffin (trade name: Paraffin Wax - 155, penetration 12, melting point 69°C, manufactured by Nippon Seiro Co., Ltd.) was applied to the surface of the granules and cooled. The obtained dried product was sieved with a sieve (JIS Z8801 - 1 - 2019; aperture 2000 μm, wire diameter 760 μm) to obtain Comparative Granule 3.

[0076] Comparative Example 4 After heating 80% by mass of the granules obtained in Comparative Example 1 to 70°C, 20% by mass of separately heated and melted solid paraffin (trade name: Paraffin Wax - 155, penetration 12, melting point 69°C, manufactured by Nippon Seiro Co., Ltd.) was applied to the surface of the granules and cooled. The obtained dried product was sieved with a sieve (JIS Z8801 - 1 - 2019; aperture 2000 μm, wire diameter 760 μm) to obtain Comparative Granule 4.

[0077] Comparative Example 5 10% by mass of sodium saccharin anhydrous and 30% by mass of solid paraffin (trade name: Paraffin Wax - 155, penetration 12, melting point 69°C, manufactured by Nippon Seiro Co., Ltd.) were heated and melted at 80°C. Separately, 60% by mass of a porous granular carrier (trade name: Isolite CG - 1, manufactured by Isolite Kogyo Co., Ltd.) heated to 80°C was impregnated with the melted liquid while stirring to form a mixture, and then the mixture was cooled. The obtained dried product was sieved with a sieve (JIS Z8801 - 1 - 2019; aperture 2000 μm, wire diameter 760 μm) to obtain Comparative Granule 5.

[0078] Comparative Example 6 As component (A), sucrose was used instead of sodium saccharin anhydrous. Sucrose (Tokyo Chemical Industry Co., Ltd., water solubility 212 g / 100 g of water) 20% by mass, solid paraffin (trade name: Paraffin Wax - 155, penetration 12, melting point 69 °C, manufactured by Nippon Seiro Co., Ltd.) 30% by mass, and barium sulfate (trade name: Barite, manufactured by Takehara Chemical Industry Co., Ltd.) 46% by mass were mixed. The obtained mixture was granulated using an extrusion granulator (Dome Gran DG - L1 type, extrusion particle diameter 1.2 mm, manufactured by Dalton Co., Ltd.). After the granulated product was roughly crushed, it was sieved using a sieve (JIS Z8801 - 1 - 2019; mesh opening 2000 μm, wire diameter 760 μm) to obtain Comparative Granule 6. Then, 4% by mass of barium sulfate was coated on the surface of the obtained Comparative Granule 6. Note that, similar to Example 1, when the temperature of the granules was measured using a non - contact thermometer (manufactured by Custom Co., Ltd., product name: IR - 210) during granulation, it was 48 °C.

[0079] Comparative Example 7 (A) As the component, L - proline was used instead of sodium saccharin anhydride. L - proline (Tokyo Chemical Industry Co., Ltd., water solubility 150 g / 100 g of water) 10% by mass, solid paraffin (trade name: Paraffin Wax - 155, penetration 12, melting point 69 °C, manufactured by Nippon Seiro Co., Ltd.) 30% by mass, and barium sulfate (trade name: Barite, manufactured by Takehara Chemical Industry Co., Ltd.) 56% by mass were mixed. The obtained mixture was granulated using an extrusion granulator (Dome Gran DG - L1 type, extrusion particle diameter 1.2 mm, manufactured by Dalton Co., Ltd.). It was sieved using a sieve (JIS Z8801 - 1 - 2019; mesh opening 2000 μm, wire diameter 760 μm) to obtain Comparative Granule 7. Then, 4% by mass of barium sulfate was coated on the surface of the obtained Comparative Granule 7. Note that, similar to Example 1, when the temperature of the granules was measured using a non - contact thermometer (manufactured by Custom Co., Ltd., product name: IR - 210) during granulation, it was 49 °C.

[0080] Comparative Example 8 (B) As the component, a solid paraffin with a penetration of less than 3 was used. 10% by mass of sodium saccharin anhydride (manufactured by Yamato Kasei Co., Ltd.), 50% by mass of solid paraffin (trade name: FT115, melting point 115°C, penetration (25°C): 1, manufactured by Nippon Seiro Co., Ltd.), and 40% by mass of barium sulfate (trade name: barite, manufactured by Takehara Chemical Industry Co., Ltd.) were mixed. The obtained mixture was granulated using an extrusion granulator (Dome Gran DG-L1 type, extrusion particle diameter 1.2 mm, manufactured by Dalton Co., Ltd.), but no particles were obtained.

[0081] Using the granules obtained in Examples 1 to 7 and Comparative Examples 1 to 7, the following dissolution test was carried out. <Dissolution test of active ingredient> 800 mL of tap water was measured into a 1 L beaker, 160 mg of the granules obtained in Examples 1 to 7 and Comparative Examples 1 to 7 were added respectively, then covered with plastic wrap and sealed, and left standing in a thermostat (model name MIR-553, manufactured by Sanyo Electric Co., Ltd.) at 20°C and 40°C. The concentration of the active ingredient in water was measured over time using high performance liquid chromatography (Alliance HPLC system, manufactured by Waters Japan K.K.), and the dissolution rate was calculated by the following calculation formula (1). The results are shown in Table 1.

[0082] <Significance of measurement at water temperature of 40°C> The temperature of paddy fields usually ranges from about 10°C to 30°C, but when the water depth is shallow, the water temperature of paddy fields may rise to about 40°C due to the intense heat in summer, the rise in air temperature due to the Foehn phenomenon, etc. Therefore, it is necessary to suppress the dissolution of the active ingredient even when the water temperature is high.

[0083]

Number

[0084]

Table 1

[0085] <Results> In the elution-controlled granules of Examples 1 to 7 of the present invention, the elution of saccharin or its salt, which is an agrochemical active ingredient, in water was suppressed over a long period (up to 56 days). Therefore, the elution-controlled granules of the present invention could be used for simultaneous seeding treatment. On the other hand, the formulations of Comparative Examples 1 to 7 had insufficient elution control.

[0086] The present invention can provide an elution-controlled granule capable of controlling the elution of saccharin or its salt having high water solubility. In addition, the elution-controlled granule of the present invention uses biodegradable solid paraffin and does not require a heating step during production, so that an environmentally considerate granule can be provided at low cost. Moreover, even when the water temperature rises in summer in paddy fields or the like, the elution of saccharin or its salt into water does not accelerate, and further, a simultaneous seeding treatment granule capable of controlling the elution rate at different water temperatures can be provided by adding an auxiliary agent or the like.

Claims

1. A first step of mixing (A) saccharin or a salt thereof and (B) solid paraffin to obtain a mixture, and A second step of granulating the mixture to obtain granules A method for producing an elution-controlled granule, comprising: The method for producing an elution-controlled granule, wherein the (B) solid paraffin has a penetration value of 3 or more and 29 or less according to Japanese Industrial Standard JIS K2235-1991 at 25°C.

2. The method for producing an elution-controlled granule according to claim 1, wherein in the first step and the second step, the (A) saccharin or a salt thereof and the (B) solid paraffin are not heated.

3. The method for producing an elution-controlled granule according to claim 1, wherein in the first step and the second step, the (A) saccharin or a salt thereof and the (B) solid paraffin are not melted.

4. An elution-controlled granule containing (A) saccharin or a salt thereof and (B) solid paraffin, The elution-controlled granule, wherein the (B) solid paraffin has a penetration value of 3 or more and 29 or less according to Japanese Industrial Standard JIS K2235-1991 at 25°C.

5. The elution-controlled granule according to claim 4, wherein the (B) solid paraffin is contained in an amount of 30 to 50% by mass based on the total mass of the elution-controlled granule.

6. The elution-controlled granule according to claim 4, wherein the (B) solid paraffin has a melting point in the range of 48°C to 90°C.

7. The elution-controlled granule according to claim 4, wherein the (A) saccharin or a salt thereof is contained in an amount of 4 to 24% by mass based on the total mass of the elution-controlled granule.

8. The elution-controlled granule according to claim 4, containing two or more kinds of the (B) solid paraffin.

9. The elution-controlled granule according to claim 4, wherein the (B) solid paraffin contains a solid paraffin having a melting point of less than 67°C and a solid paraffin having a melting point of 67°C or more.

10. The elution-controlled granule according to claim 4, capable of controlling the elution of saccharin or a salt thereof at a water temperature of 40°C.

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