JPH0881292A - Coated fertilizer - Google Patents

Abstract

PURPOSE: To obtain a delayed release highly coated fertilizer having a water- repelling property and a microorganismic decomposition-inhibiting ability by coating a fertilizer with a melted mixture liquid comprising a coumarone resin and a wax. CONSTITUTION: A coumarone resin having a melting point of approximately 70-160 deg.C in an amount of 5-95wt.% and 5-95wt.% of a wax having a melting point of approximately 50-100 deg.C are thermally melted to obtain a perfectly compatibilized mixture melted liquid for coating. A fertilizer having a particle diameter of 1-4mm are heated under stirring, and simultaneously sprayed with the obtained mixture melted liquid for the coating to obtain the coated fertilizer. Or, the mixture melted liquid for the coating is cooled, ground into the ground product having particle diameters of <=0.5mm, and subsequently mixed with a fertilizer having the particle diameter of 1-4mm. The mixture is stirred and simultaneously heated to obtain the coated fertilizer wherein the coating material is melted and coated. The coating amount of the coating layer is preferably 5-30wt.% based on the particulate fertilizer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coated fertilizer having a high slow release effect, which has a coating layer composed of a homogenous molten mixture of coumarone resin and waxes.

[0002]

[Description of the Prior Art] As a method for slowing down fertilizer, a slow-moving fertilizer such as oxamide which is not immediately used by plants is used, and contact between fertilizer and soil or water is blocked. Therefore, there are a method of using a coated fertilizer, a method of using a fungicide-containing fertilizer for suppressing mineralization by soil microorganisms, a method of combining these methods, and the like. Among these methods, a waterproof coating material is used in the production of a coated fertilizer in which the contact between the fertilizer and soil or moisture is blocked.

Examples of such coating materials include waxes (wax, paraffin, etc.), diene polymer (butadiene polymer, isoprene polymer, butadiene / styrene copolymer, styrene / isoprene copolymer, etc.), olefin. Polymers (polyethylene, etc.), Copolymers containing olefin polymers (ethylene, vinyl acetate copolymers, etc.),
Vinylidene chloride polymers, copolymers containing vinylidene chloride (vinylidene chloride / vinyl chloride copolymers, etc.), petroleum resins, natural resins (natural rubber, rosin, etc.), solid fatty acids, etc. are known.

In the coating step, these polymers are dissolved in an organic solvent (hydrocarbons such as toluene, xylene, tetrachloroethylene, and trichloroethylene that are not chlorinated or are not dissolved) in an amount of 1 to 10%. After coating the fertilizer with the coating material solution, the step of recovering the organic solvent by heating was essential.

[0005]

The object of the present invention is to eliminate the need for using an organic solvent to dissolve the coating material, and to provide the coating layer with excellent water-repellent waterproof property, thereby achieving a high slowing effect. The purpose of the present invention is to provide a coated fertilizer having a very slow release effect, which is imparted with the property and further has the ability of the coating material to suppress microbial decomposition.

[0006]

The above object of the present invention is to use a molten mixed solution of coumarone resin, which is a spreading coating material, and waxes to remove a part or all of the fertilizer surface or / and voids. This is achieved by controlling the thickness and coating of layers or layers. Hereinafter, the present invention will be described in detail.

The coumarone resin is a solvent naphtha (boiling point of 150 to 200) contained in light oil in coke oven gas.
° C. Is a raw material and is a thermoplastic resin obtained by copolymerizing coumarone, indene, styrene, etc. contained in the raw material. The coumarone resin is not particularly limited as long as the object of the present invention can be achieved, and examples thereof include those having a melting point of 70 to 160 ° C. And, as such, G-90 (melting point 90 ° C.) of Esclone, N-1
Examples include coumarone of grades such as 00 (melting point 100 ° C.) and V-120 (melting point 120 ° C.) (all manufactured by Nippon Steel Chemical Co., Ltd.).

The waxes are not particularly limited as long as the object of the present invention can be achieved. , Microcrystalline wax, petrolactam); preferably having a melting point of 5
0 to 100 ° C .; more preferably 60 to 8
It is 0 ° C. [rice bran wax [A wax and / or B wax manufactured by Kaneko Warehouse Co., Ltd. (the melting point of each wax is 60 ° C.)]. The difference in melting point between the coumarone resin and the waxes is not particularly limited as long as the object of the present invention can be achieved, and in consideration of the temperature rising process for melting in the same mixing tank, the coumarone resin having a high melting point is used. It is preferably the same temperature as the melting temperature.

As the fertilizer, urea, sodium nitrate, acetaldehyde condensed urea, isobutyraldehyde condensed urea,
Nitrogen fertilizers such as oxamide; Phosphate fertilizers such as fertilizer, calcined phosphate fertilizer, processed phosphate fertilizer, mixed phosphate fertilizer, and humic acid phosphate fertilizer; sulfate potassium, chloride chloride, potassium sulfate magnesia, heavy Examples of the fertilizer include potassium fertilizer such as carbonate and silicate; chemical fertilizer such as phosphoric acid and nitrate; organic fertilizer; and a mixture of these fertilizers.

The type of fertilizer is not particularly limited as long as the object of the present invention can be achieved, but since controlling the nitrogen supply amount is important in crop cultivation, in order to obtain a fertilizer having a very slow release rate, In addition to spread coating, it is preferable that the fertilizer used is a slow-release fertilizer such as oxamide. The shape of the fertilizer is not particularly limited as long as the object of the present invention can be achieved, but granules are preferable in view of efficiency in the spread coating step of production. The particle size of such granular fertilizer is not particularly limited, but is preferably 1 to 4 mm from the conventional practice of fertilization.

Uniform mixing of the coumarone resin and the waxes is usually carried out by mixing the necessary amounts of the coumarone resin and the waxes and then completely melt-liquefying and mixing sufficiently uniformly (method of melting after mixing), Alternatively, it can be carried out by separately melting and liquefying the required amounts of both and then mixing them sufficiently uniformly (method of mixing after melting); the method of melting after mixing is preferred. In the method of melting after mixing, if the particle size of the obtained coumarone resin or wax is 1 mm or more, the particles can be collectively melted at 1 mm or less, preferably 0 It is preferable to pulverize it to 1 mm or less.

The amount of coumarone resin used is 5 to 95%; preferably 10 to 80%; more preferably 25 to 50%. If the amount of coumarone resin used is less than the above range, the characteristics of waxes are too strong, and for example, the fertilizer having a gap (for example, particle size) because the solution viscosity becomes too low in the spreading coating process of fertilizer. 2m
(granular fertilizers such as oxamide having a size of m or more) have higher impregnating properties, the proportion of fertilizer components such as nitrogen component in the obtained coated fertilizer is low, the hardness becomes too small, and the coating layer becomes thin to shield. This is because the effect is poor and the effect of blocking contact between fertilizer and soil or water is reduced.

On the other hand, even if the amount of coumarone resin used is more than the above range, the characteristic of coumarone resin is too strong, and for example, the solution viscosity becomes too high in the spreading coating process of fertilizer, resulting in poor dispersibility. This is because a fertilizer having a gap has poor impregnation property, hardness increases, cracks occur, and the effect of blocking contact between the fertilizer and soil or moisture decreases. The melting temperature of the coumarone resin and waxes does not decompose from the melting point of the coumarone resin of each of the above grades in order to obtain a uniform coating of fertilizer using the molten mixture of both and a large densification of the coating. Within the melting temperature range;
It is preferably 80 to 160 ° C .; more preferably 9
It is 0 to 130 ° C.

The coating amount of the coating layer and the number of coating layers can be arbitrarily changed according to the desired release rate of the fertilizer component. The coating amount is preferably 5 to 30%, and more preferably 8 to 16% of the amount of granular fertilizer. If the coating amount of the coating layer is less than the above range, it is difficult to control the coating amount of the coating layer according to the design value during the production of coated fertilizer (the smaller the coating amount of the coating layer, the more error The allowable range becomes narrower), and the mechanical strength of the coating layer is reduced, and the coating layer may be damaged during transportation and storage, which may cause the above problems.

On the other hand, even if the spread coating amount of the coating layer is more than the above range, the release control effect of the fertilizer is not further enhanced, and the spread coating material is made oily so that the coating material and the coated fertilizer are integrated into granular particles. This is because the tendency of the fertilizer component to increase, the content rate of the fertilizer component relatively decreases, and the amount of the spread coating material remaining in the soil after the fertilizer is released increases. And
If it is attempted to obtain a granular fertilizer having a desired shape by dispersing the formed aggregated granules, the coating layer of the contact portion of the granules forming the aggregated granules will peel off,
The content of defective coated granular fertilizer will increase.

As the multi-layered coated fertilizer, a coating layer consisting only of coumarone resin and waxes, another coating layer (for example, a layer consisting of an alkaline substance described in JP-A-4-202078), and an olefin polymer. And a coating layer having a layer composed of an alkali water-soluble polymer) in an appropriate combination. The formation of a multi-layer coating layer using only a mixed solution of coumarone resin and waxes is better than that of the coumarone resin and waxes used in the formation of the first coating layer (the layer coated so as to directly contact the fertilizer surface). A second coating layer is formed on the solidified outer surface of the first coating layer by using a material having a low melting point, and this process is repeated in the same manner, whereby the third coating layer,
The coating can be carried out as a fourth coating layer, a fifth coating layer, ... (The grade of coumarone resin used is a high temperature grade to a low temperature grade).

The total amount of the coumarone resin and waxes used is 5 to 30%, preferably 10 to 20, relative to the fertilizer.
%, And more preferably 8 to 16%. If the total amount of both used is less than the above range, it tends to be difficult to completely cover the entire fertilizer surface even if the spread coating state has some unevenness, and the fertilizer to be used has impregnability. This is because there is an increasing tendency for the amount required for spread coating to become insufficient. On the other hand, even if the total amount of use of both is larger than the above range, the release control effect of fertilizer is not further enhanced,
This is because the oil content of the spread coating material increases the tendency of the coating material and the coated fertilizer to form a united granular body, and the content rate of the fertilizer component relatively decreases.

At this time, the fertilizer is preheated at 90 to 150 ° C.
It is preferably heated to 100 to 120 ° C. The coated fertilizer of the present invention is crushed, crushed, melted, uniformly mixed, coated with fertilizer, cooled and solidified with coated fertilizer, and prevents coalescence of coated fertilizer under temperature control (40 to 150 ° C.). It can be produced by using a commonly used apparatus capable of performing the production process of [for example, Nauta mixer (midget machine, NX type) manufactured by Hosokawa Micron Co., Ltd.].

The particle size of the coated fertilizer thus obtained is not particularly limited, but is 2-5 mm according to the practice of fertilization.
Is preferred. When the fertilizer to be used is granular and has gaps, the coated fertilizer is 120-
A portion of the gap is impregnated with the molten mixture of the spread coating material at a high temperature of 140 ° C., and further impregnated with the same mixture of the spread coating material at a low temperature of 90 to 110 ° C. to further spread the surface of the granular fertilizer. By applying and coating the product, it is possible to prevent the product from losing its shape and to further enhance its slow-release effect.

The coated fertilizer of the present invention is the one on which this coated fertilizer serves as a base for crop cultivation; in order to achieve good growth of the fertilizer, pesticides (herbicides, insecticides) further required. , Fungicides, etc., plant regulators, micronutrients, etc., inside the first coating layer and / or between the coating layers,
It can be additionally mixed with fertilizer. When it is necessary to additionally mix these, the above-mentioned respective components serving as a base for crop cultivation and a fertilizer are mixed.

The coated fertilizer thus obtained is considered to exhibit fertilizing effect in soil as described below. First, it is considered that water containing microorganisms (environmental water) and air penetrate into the fertilizer from the porous portion of the thin spreading coating layer, dissolve the fertilizer component, and release this fertilizer component to the outside of the fertilizer. To be At this time, the microorganisms cause the coating layer to become porous; a larger amount of water passes through the coating passage from the outside into the fertilizer inside to dissolve and disperse the fertilizer components. It is considered that they pass through and are released to the outside. At this time, when the fertilizer used is a slow-release fertilizer such as oxamide, in parallel with the slow-release fertilizer being mineralized by soil microorganisms,
In some cases, the mineralized substance is taken up by the microorganism and becomes a constituent component of the microbial cell, so that it is slowly re-activated.

Therefore, in the coated fertilizer of the present invention, by selecting the mixing ratio of the components of the coating layer and the spread coating amount (film thickness) of the coating layer, coating based on the amount of permeated water of the coating layer and the action of soil microorganisms can be performed. It is possible to control the start time of water permeation of the layer. As described above, the coated fertilizer can start the release of the fertilizer component at any necessary time during the growth of the crop. For cultivation, a combination of coated fertilizers having different start times of release of fertilizer components can be used.

[0023]

EXAMPLES The present invention will be specifically described below with reference to examples. It should be noted that these examples do not limit the scope of the present invention. Example 1 [Production of one-layer coated fertilizer] Coumaron resin (80 g) (ESCLON G manufactured by Nippon Steel Chemical Co., Ltd.
-90. Melting point 90 [deg.] C. ) And wax (160 g) (B wax manufactured by Kanemi Warehouse Co., Ltd., melting point 60 ° C.).
It was placed in a 500 ml stainless steel cylindrical container that had been heated to 20 ° C., heated at the same temperature to melt, and mixed with a blade stirrer at 200 rpm for 10 minutes to obtain a completely compatible mixed melt. . Oxamide (60 g) [Oxamide grain / GO (particle size 2 to 4 mm, hardness 1.6 to 2.0 kg) manufactured by Ube Industries, Ltd.] was placed in a 500 ml stainless steel cylindrical container and stirred using an anchor stirrer. (50 rp
m) while raising the temperature to 80 ° C., and spray-adding the above-mentioned completely compatible mixed melt (9 ml), and further adding 1
Stirred at 20 rpm for 10 minutes. This is further heated to 120 and further mixed at 100 rpm for 5 minutes, and then 4
By cooling to 0 ℃, 66 g of the target coated fertilizer
Obtained.

Example 2 [Production of a layer of coated fertilizer sufficiently impregnated with coating agent] Coumaron resin (80 g) (ESCLON G manufactured by Nippon Steel Chemical Co., Ltd.)
-90. Melting point 90 [deg.] C. ) And wax (120 g) (B wax manufactured by Kanemi Warehouse Co., Ltd., melting point 60 ° C.).
The mixture was placed in a 500-ml stainless steel cylindrical container that had been heated to 20 ° C., heated at the same temperature to melt, and mixed with a blade stirrer at 200 rpm for 10 minutes to be completely compatible. After cooling to -10 ° C, a stirrer (National MX-1
51S) and crushed at 11,000 rpm for 5 minutes,
By sieving, a pulverized product having a particle size of 0.5 mm or less was obtained. The obtained crushed material (0.5 mm or less) (8.2 g)
And oxamide (60g) [Oxamide granules / GO (particle size 2-4mm, hardness 1.6-2.0k manufactured by Ube Industries, Ltd.
g)] was put in a 500 ml stainless steel cylindrical container, and mixed and dispersed at room temperature for 2 minutes at 50 rpm using an anchor type stirrer.

This mixture is put in the same container for 120-150.
While stirring at rpm, the temperature was raised to 120 ° C., and further stirred at 100 to 120 rpm for 10 minutes to prevent the spreadable coating material from becoming oily and to spread the coating uniformly so as not to form aggregated particles. 4 with hot blaster cold air
Bubbling cool to 0-45 ℃, the target coated fertilizer 67
g was obtained. The shielding effect of this coated fertilizer was evaluated by obtaining the decomposition rate of the coated fertilizer measured as follows. The coated fertilizer (10 g) was placed in a mesh bag of 0.5 mm and the total organic acid content (TDO) was 5,000.
It was immersed in a 20 L container containing sludge having an oxamide-decomposing ability of ~ 7,000 ppm, pH 2.5-3.0, and SS concentration of 4,000-5,000 ppm. Dissolved oxygen (D
The water-soluble substance is removed by removing the bag on the 7th, 14th, 21st, and 27th days while watering the air so that the (O value) becomes 1.5 to 1.8 ppm. Removed,
After drying, the residual weight (%) was measured to determine the decomposition rate (%) of the coated fertilizer. The results are shown in FIGS. 1 and 2.

Example 3 [Production of two-layer coated fertilizer] Coumaron resin (80 g) (ESCLON V manufactured by Nippon Steel Chemical Co., Ltd.)
-120. Melting point 120 [deg.] C. ) And wax (120 g)
(B wax manufactured by Kanemi Warehouse Co., Ltd., melting point 60 ° C.)
And were placed in a 500 ml stainless steel cylindrical container heated to 120 ° C., heated at the same temperature to melt, and mixed with each other at 200 rpm for 10 minutes using a blade stirrer to completely dissolve each other. After cooling to -10 ° C, stirrer (National MX
-151S), pulverized at 11,000 rpm for 5 minutes, and sieved to obtain a pulverized product having a particle size of 0.5 mm or less. The obtained crushed material (0.5 mm or less) (8.2
g) and oxamide (60 g) [Oxamide particles / GO (particle size 2 to 4 mm, hardness 1.6 to 2.
0 kg)] was put in a 500 ml stainless steel cylindrical container and mixed and dispersed at room temperature for 2 minutes at 50 rpm using an anchor stirrer. This mixture is put in the same container at 120-
While stirring at 150 rpm, the temperature was raised to 120 ° C., and then the mixture was further stirred at 100 to 120 rpm for 10 minutes to prevent the spreadable coating material from becoming oily and uniformly spread-coated so as not to form aggregated particles. Bubbling cooling was performed to 50 ° C. with a hot blaster cold air to obtain a further impregnated coated fertilizer.

The crushed product obtained in Example 2 (1.2 g)
Was added with stirring at 100 rpm, then the temperature was raised to 100 ° C. and 80 rpm was added so as not to form a united body due to oilification.
A uniform dispersion spread coating was performed by stirring at. Bubbling cooling was performed at 40 to 45 ° C. with a hot blaster cold air to obtain 65 g of a two-layer coated fertilizer. The shielding effect of the produced two-layer coated fertilizer was measured using the above-mentioned two-layer coated fertilizer in the same manner as in Example 2. The result is shown in FIG. In addition, as a control for these, the result of obtaining the decomposition rate of the fertilizer in the same manner as in Example 2 using the granular fertilizer (uncoated granular fertilizer) which is not covered with oxamide grains and GO manufactured by Ube Industries, Ltd. Shown in 1.

Comparative Example 1 [Production of Coated Fertilizer Consisting Only of Wax] (1) Production of Coated Fertilizer with Less Wax Impregnation Wax (160 g) (B wax manufactured by Kanemi Warehouse Co., melting point 60 ° C.). ) Was cooled to −10 ° C. and then put in a stirrer (National MX-151S) to obtain 11,000 rp.
Grinding for 5 minutes at a diameter of 1 mm by sieving
The following ground product was obtained. Oxamide (60 g) [oxamide granules / GO (particle size 2-4 mm, hardness 1.6-2.0 kg) manufactured by Ube Industries, Ltd.] was placed in a 500 ml stainless steel cylindrical container and heated to 60 ° C., The above-mentioned pulverized product of wax (6 g) was added at 80 rpm, the temperature was raised to 75 ° C. with stirring, and the mixture was further dispersed and spread by stirring at 60 rpm for 10 minutes, and then hot blaster cold air with stirring at 60 rpm. 63 g of wax-coated fertilizer was obtained by bubbling cooling to 40-45 ° C. The shielding effect of this coated fertilizer was measured in the same manner as in Example 2, and as a result, the decomposition rate was 22.5%.

(2) Manufacture of coated fertilizer sufficiently impregnated with wax Oxamide (60 g) [Oxamide granules / GO manufactured by Ube Industries, Ltd. (particle diameter 2-4 mm, hardness 1.6-2.0 k
g)] was placed in a 500 ml stainless steel cylindrical container and heated to 60 ° C., and the pulverized product of wax (1) (8.2 g) was added thereto at 120 rpm and stirred at 90 ° C.
66 g of fertilizer impregnated with wax by bubbling to 40-45 ° C. with hot blaster cold air while stirring at 60 rpm to uniformly disperse and spread by further raising the temperature to 120 rpm and stirring at 120 rpm for 10 minutes. It was The shielding effect of this coated fertilizer was measured in the same manner as in Example 2. The result is shown in FIG.

Comparative Example 2 [Manufacture of Coated Fertilizer Consisting Only of Coumaron Resin] Coumaron Resin (80 g) (ESCLON G manufactured by Nippon Steel Chemical Co., Ltd.
-90. Melting point 90 [deg.] C. ) Was cooled to −10 ° C. and then put in a stirrer (National MX-151S) to obtain 11,000
Grind for 5 minutes at rpm and sieve to obtain a particle size of 1
A pulverized product having a size of mm or less was obtained. Obtained pulverized product (8.2 g)
And oxamide (60g) [Oxamide granules / GO (particle size 2-4mm, hardness 1.6-2.0k manufactured by Ube Industries, Ltd.
g)] and 500 ml of a stainless steel cylindrical container, and stirred at room temperature at 120 to 150 rpm for 5 minutes, and then at 100 to 130 ° C. using an anchor type stirrer for 100 to 1
66 g of fertilizer coated with coumarone resin was obtained by stirring at 20 rpm for 10 minutes. The shielding effect of this coated fertilizer was measured in the same manner as in Example 2. The result is shown in Figure 2.
Shown in In addition, as a control, the result of obtaining the decomposition rate of the fertilizer in the same manner as in Example 2 using granular fertilizer (uncoated granular fertilizer) which is not coated with oxamide grains / GO manufactured by Ube Industries, Ltd. is shown in FIG. Show.

[0031]

INDUSTRIAL APPLICABILITY The coated fertilizer of the present invention does not require the use of a solvent in the production process, and has a slower release effect than that when only one of coumarone resin and wax is used as a coating material. .

[Brief description of drawings]

FIG. 1 shows “each coated granular fertilizer obtained by further coating oxamide with a uniform mixture of coumarone resin and waxes” shown in Example 2 (denoted by Δ), Example Three
“Coated granular fertilizer obtained by coating oxamide with a uniform mixture of coumarone resin and waxes in two layers” (marked with ○) and “uncoated granular fertilizer” (marked with ×) It is a figure which shows the decomposition rate (%) when immersed in the activated sludge tank.

FIG. 2 shows “coated granular fertilizer obtained by further coating oxamide with a uniform mixture of coumarone resin and waxes” shown in Example 2 (denoted by Δ), Comparative Example 1 of
"Coated granular fertilizer obtained by coating only one layer with waxes" (denoted by ●) shown in (2), and "Coating obtained by coating only one layer with coumarone resin" shown in Comparative Example 2 It is a figure which shows the decomposition rate (%) when immersed in the activated sludge tank of "granular fertilizer" (represented by *) and "uncoated granular fertilizer" (represented by x).

Claims (1)

[Claims] 1. A coumarone resin 5 to 95% and a wax 5
Coated fertilizer having a coating layer formed of a homogeneous melt mixture with ~ 95%.