JPH10231190A - Coated fertilizer and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coated fertilizer excellent in mechanical strength, elution controlling properties and environmental degradability. SOLUTION: The surface of a granular fertilizer is coated with a coating film comprising 10-90wt.% based on the total weight of the coating film of a polyolefin having 300-10,000 weight-average molecular weight and/or petroleum wax, 5-60wt.% of a polyolefin having >=10,000 weight-average molecular weight and 0.02-20×10<-6> mol/g of one or more organic metal complexes selected from among iron, cobalt, nickel, copper, manganese, palladium, molybdenum, chromium, tungsten and cerium. The total weight of the coating film is 1-50wt.% based on the granular 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 in which the surface of a fertilizer is coated with a resin or the like, and more particularly to a granular fertilizer coated with a film having excellent degradability in a natural environment. is there.

[0002]

2. Description of the Related Art Conventionally, the following techniques have been known for making fertilizer slow-release. First of all, chemical slow-release fertilizers. This is CDU Kasei or I
This is a technique for controlling elution of fertilizer components by a chemical reaction having a constant reaction rate, as represented by B chemical conversion. Secondly, the elution of fertilizer inside is controlled by coating the surface of the fertilizer with a fixed film.

[0003] Several types of coatings are known so far. That is, first, the granular fertilizer is coated with a film containing sulfur as a main component. However, sulfur has the disadvantage that its oxides cause acidification of the soil and the mechanical strength is extremely poor. The second is an alkyd resin. The alkyd resin also has poor mechanical strength, and particularly poor impact resistance and abrasion resistance, and as a result, it has not been possible to develop a satisfactory slow action, that is, dissolution controllability. Third is a urethane-based resin. Urethane-based resins have relatively high mechanical strength, but have problems such as manufacturing problems and high cost. Fourth is a polyolefin-based resin. Although this resin has excellent mechanical strength and excellent elution characteristics, the degradability of the film after elution in a natural environment is not always satisfactory.

Further, Japanese Patent Publication No. 54-3104 discloses that a polyolefin wax having a relatively small molecular weight can be used as a coating material by mixing a normal polyolefin with a polyolefin wax. However, it is described that the wax has low strength and cannot be used alone. Japanese Patent Publication No. 44-16330 discloses a method for improving fluidity, coating properties and the like by using a petroleum wax and a polyethylene wax having a molecular weight of 1,000 to 5,000 in combination.

Some attempts have been made to improve the decomposability of the film after the elution of the fertilizer components is completed. A typical one of these methods is an application of so-called photolysis or biodegradation. As a biodegradability application, for example, Japanese Patent Application Laid-Open No. 3-146492 discloses a technique using polycaprolactone.
Japanese Patent Application Laid-Open No. 7-33577 discloses a technique using an aliphatic polyester, and Japanese Patent Application Laid-Open No. 7-33577 discloses a technique using polylactic acid. On the other hand, as a technique to which photolysis is applied, for example, a technique using an organic metal as described in Japanese Patent Publication No. Hei 7-91143 is known.

[0006] However, none of these prior arts can sufficiently satisfy mechanical strength, dissolution controllability, film decomposability, productivity and the like at the same time.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a coated granular fertilizer which can sufficiently satisfy the above-mentioned mechanical strength, dissolution controllability, film decomposability, and productivity at the same time.

[0008]

Means for Solving the Problems As a result of intensive studies on the above problems, the present inventors have found that two kinds of polyolefin or petroleum wax having a specific molecular weight have a specific amount,
In addition, they have found that a coated fertilizer containing a specific amount of a specific organometallic complex solves the above problems, and have completed the present invention.

That is, the present invention is as follows. (1) The surface of the granular fertilizer is a polyolefin having a weight average molecular weight of 300 to 10,000 and / or a petroleum wax of 10 to 90% by weight, and a polyolefin having a weight average molecular weight of more than 10,000 based on the total weight of the film. 5-
60% by weight and iron, cobalt, nickel, copper,
Coated with a film containing at least one organometallic complex selected from manganese, silver, palladium, molybdenum, chromium, tungsten, and cerium in an amount of 0.02 to 20 × 10 ^-6 mol / g; A granular coated fertilizer, wherein the total weight of the coating is 1 to 50% by weight. (2) 10 to 90% by weight of a polyolefin and / or petroleum wax having a weight average molecular weight of 300 to 10,000 using a tumbling or jetting device, and a weight average molecular weight of 1
5 to 60% by weight of a polyolefin greater than 000, and one or more organometallic complexes selected from iron, cobalt, nickel, copper, manganese, silver, palladium, molybdenum, chromium, tungsten, and cerium are dispersed (dissolved). 2. The coating according to claim 1, wherein a film is formed on the surface of the granular fertilizer by a dispersion (solution) containing 0.02 to 20 * 10 < ^-6 > mol / g with respect to the total solid content of the liquid. Manufacture of fertilizer.

The term "dispersion (solution) liquid" means that each component used is in the form of a solution or dispersion, and is described in detail below. Hereinafter, the present invention will be described in detail. The polyolefin in the present invention is a so-called high-density or low-density polyethylene, and polypropylene, ethylene-propylene copolymer, polybutene, butene-ethylene copolymer, butene-propylene copolymer, and the like. Among them, polyethylene and polypropylene, and among them, polyethylene can be preferably used.

In addition to those obtained by ordinary polymerization reactions, polyolefins include those obtained by reducing the molecular weight of a high molecular weight substance by thermal decomposition or oxidative decomposition. Of course, these substances can also be used. Further, those modified with a small amount of a functional group such as a carboxyl group can also be used. The petroleum wax in the present invention refers to so-called paraffin wax, microcrystalline wax and petroleum wax called petrolatum.

In the present invention, among these, a polyolefin having a weight average molecular weight of 300 to 10,000 and / or a petroleum wax (hereinafter abbreviated as POA) and a polyolefin having a weight average molecular weight of more than 10,000 (hereinafter, referred to as POA). POB). POA is a polyolefin and / or petroleum wax having a weight average molecular weight of 300 to 10,000, preferably 500 to
It is 8,000, more preferably 500 to 5,000. Among the polyolefins, polyethylene, particularly polyethylene having a weight average molecular weight of 500 to 5,000 can be suitably used. These may be used alone or as a mixture. The weight average molecular weight of the polyolefin and / or petroleum wax is 300
If it is less than 10, the mechanical strength of the coated granular fertilizer will be greatly reduced, while if it exceeds 10,000, there will be a problem in the decomposability of the film. The molecular weight distribution may have a broad distribution or may have a so-called bimodal distribution. POA is 1 in the film
It is 0 to 90% by weight, preferably 10 to 50% by weight.

POB is a polyolefin having a weight average molecular weight greater than 10,000. Above all, 10,000
Polyolefins greater than 0, up to 100,000, more preferably 15,000 to 80,000 are suitably used. If the weight-average molecular weight is less than 10,000, a problem arises in mechanical strength including abrasion in practical use. When the molecular weight is larger than a certain value, attention must be paid to the solubility in a solvent. The POB may have a broad molecular weight distribution or may have a so-called bimodal distribution. In terms of the MI value used as a standard, POB is 0.1 to 10
It is possible to use about zero. POB is 5 to 60% by weight in the coating, preferably 5 to 3% by weight.
0% by weight. The weight ratio between POA and POB is preferably 1 or more, more preferably 3/2 or more.

In the present invention, the molecular weight of the polyolefin is determined by gel permeation chromatography (GPC).
Refers to the weight average molecular weight measured by
The coating of the coated fertilizer in the present invention contains an organometallic complex. The organometallic complex is at least one organometallic complex selected from iron, cobalt, nickel, copper, manganese, silver, palladium, molybdenum, chromium, tungsten, and cerium. Preferred complexing agents include acetylacetone. Β-diketones, β-ketoesters, and dialkyldithiocarbamates, dialkyldithiophosphates, alkylxanthates, and mercaptobenzothiazole. When two or more kinds of organometallic complexes are used in combination, a great effect may be obtained. In some cases, a combination of a transition metal complexed via oxygen and a transition metal complexed via sulfur is preferable, and the molar ratio thereof is 2
It is preferable that it is above. Among these organometallic complexes, iron and / or nickel are particularly preferred, and more specifically, nickel dibutyldithiocarbamate, nickel diethyldithiocarbamate, acetylacetone complex of iron, and the like.

The total amount of the organometallic complex is based on the weight of the coating layer.
It is preferably in the range of 0.02 to 20 × 10 ⁻⁶ mol / g, and particularly preferably in the range of 0.1 to 10 × 10 ⁻⁶ mol / g. The coating of the present invention can contain other resins, inorganic additives, organic additives, emulsifiers, other additives, and the like, in addition to the polyolefin, petroleum wax, and organometallic complex.

As the resin, polystyrene, polymethyl (meth) acrylate (characters in parentheses may or may not be read; the same applies hereinafter), ethylene
Vinyl acetate copolymer, ethylene / (meth) acrylic acid copolymer, ethylene / (meth) acrylic acid ester copolymer, ethylene / carbon monoxide copolymer, polyvinyl chloride,
Use diene (co) polymers such as polyvinylidene chloride, vinyl chloride / vinylidene chloride copolymer, polybutadiene, polyisoprene, polychlorobrene, butadiene / styrene copolymer, EPDM, and styrene / isoprene copolymer. be able to. In addition to these, natural resins such as petroleum resin, natural rubber and rosin, hardened oils, fats and oils such as solid fatty acids, and modified products thereof, waxes such as beeswax and wood wax can also be used. These resins can be used for the purpose of the present invention, but are usually up to 40% by weight, preferably up to 20% by weight.

As the inorganic additive, talc, clay, calcium carbonate, bentonite, silica, diatomaceous earth, metal oxides such as titanium oxide, sulfur powder and the like can be suitably used. The content of the inorganic additive such as talc is 80% by weight or less, preferably 70% by weight or less. As the organic additive, starch and powders such as modified starch, agar, xanthone and the like, and optionally cross-linked polystyrene or polymethyl methacrylate can be used. Organic additives such as starch are 30% by weight or less, preferably 15% by weight.
It is as follows. The type and amount of these additives affect the mechanical strength, dissolution, decomposability, etc. of the film, and the amount should be determined in consideration of this point. For example, talc and other inorganic additives do not inherently have a problem of decomposability, and from this point of view, it is possible to mix a large amount of them, and on the other hand, they also have the effect of increasing the specific gravity of the film. This results in a decrease in film strength. Further, since a hydrophilic polymer such as starch greatly affects dissolution controllability, the amount should be determined in consideration of this point of view.

There is no particular limitation on the emulsifier that can be used, and conventionally known emulsifiers such as anions, nonions and cations can be used. Among them, nonionic emulsifiers having a polymerization unit of ethylene oxide are preferred. . From the viewpoint of the production of the coated fertilizer of the present invention, the emulsifier is preferably determined in consideration of the solubility in a solvent described below. That is, when the emulsifier is insoluble in the solvent used at the time of production, defects such as poor reproducibility of elution are produced. The emulsifier is usually
The range is 10% by weight or less.

The coated fertilizer of the present invention is a coated fertilizer comprising the above-mentioned film formed on the surface of a granular fertilizer. There is no particular limitation on the granular fertilizer, and conventionally known ones can be used. To list preferred embodiments, urea, aldehyde condensed urea,
Nitrous organic compounds such as isobutyraldehyde condensed urea, formaldehyde condensed urea, guanyl urea oxamide, etc., ammonium compounds such as ammonium nitrate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, ammonium sulfate, ammonium chloride, potassium nitrate, potassium phosphate potassium sulfate, potassium chloride Potassium salts, calcium salts such as calcium phosphate, calcium sulfate, calcium nitrate, calcium chloride, etc., magnesium salts such as magnesium nitrate, magnesium chloride, magnesium phosphate, magnesium sulfate, ferrous nitrate, ferric nitrate, phosphoric acid Use iron salts such as iron, ferric phosphate, ferrous sulfate, ferric sulfate, ferrous chloride, and ferric chloride, and double salts thereof, or a complex of two or more thereof. Can be. These granular fertilizers may contain a conventionally known binder for the purpose of maintaining the form and mechanical strength of the granular fertilizer. Examples of the binder include molasses, ligninsulfonate, and modified products thereof.

The coated fertilizer of the present invention is a coated fertilizer in which the above-mentioned film is formed on the surface of a granular fertilizer. In addition, a second layer is formed at an arbitrary place so as not to impair the effects of the present invention. It may be. For example, a layer having an appropriate adhesive property can be interposed between the inner fertilizer and the film in order to improve the adhesive strength. Conventionally known adhesives can be used as these adhesives, but those having high mechanical strength and high decomposability are preferable in light of the object of the present invention. Further, the surface of the coating may be surface-treated. For example, it is possible to treat with an inorganic powder for the purpose of improving the blocking of fertilizer particles, or to coat with wax or the like for the purpose of improving the angle of repose.

The total weight of the coating layer relative to the granular fertilizer inside is 1 to 50% by weight, preferably 3 to 20% by weight, and more preferably 3 to 15% by weight. Exceeding this lower limit makes it difficult to control the eluted components as fertilizer. In addition, when the value exceeds the upper limit, there is a problem that the quality of the fertilizer deteriorates. The particle size of the coated fertilizer of the present invention is not particularly limited, but is usually 0.5 to 10
mm, preferably 1 to 5 mm.

Next, a method for producing the coated fertilizer of the present invention will be described. As the jet apparatus used in the production method of the present invention, various conventionally known apparatuses can be used. Regarding these devices, for example, Japanese Patent Publication No. 54-3104
No. 6,086,045. That is, it is a device in which a blower for sending hot air, a solution pump for sending a coating dispersion (solution) solution, a spray nozzle, a thermometer, and the like are attached to the jet tower body. A granular fertilizer to be coated is introduced into the spout tower, and a gas at a predetermined temperature is blown from a blower or the like to adjust so that a jet of the fertilizer occurs stably in the tower. When the temperature in the tower reaches a desired temperature, a predetermined dispersion (solution) solution is supplied from a spray nozzle to form a first layer film on the surface of the granular fertilizer. In this case, conditions such as the temperature and the amount of air can be appropriately changed depending on the liquid composition and the like.

The coated fertilizer of the present invention can be produced not only by a method using a spout tower but also by other devices such as a rolling coating device. There is no particular limitation on granular fertilizer,
Those described above can be used. The particle size of the granular fertilizer may be appropriately set in consideration of the target particle size of the final product and the weight of the film. The shape of the granular fertilizer can greatly affect the performance of the coated fertilizer, and is preferably spherical. If the deviation from a true sphere is large, the dissolution and mechanical strength may be adversely affected.

Next, dispersion (melting) for forming a film
The liquid will be described. The dispersion (solution) is a polyolefin having a weight average molecular weight of 300 to 10,000 and / or a petroleum wax of 10 to 90% by weight based on the solid content, and a polyolefin having a weight average molecular weight of more than 10,000
60% by weight, and one or more metal complexes selected from iron, cobalt, nickel, copper, manganese, silver, palladium, molybdenum, chromium, tungsten, and cerium. 0.02 to 20 ×
It is a dispersion (solution) solution containing 10 ^-6 mol / g.

As the preferred embodiments of the polyolefin or petroleum wax, those described above can be used. The dispersion (solution) liquid can contain other resins, inorganic and organic additives, emulsifiers, and other additives described above, in addition to the polyolefin, petroleum wax, and organometallic complex. Normally used ranges of inorganic additives, organic additives, organometallic complexes, emulsifiers, etc. are based on solid components,
The content of inorganic additives such as talc is 80% by weight or less, preferably 7% by weight.
0% by weight or less, and the amount of organic additives such as starch is 30%.
% By weight, preferably 15% by weight or less, and the emulsifier is usually used in a range of 10% by weight or less.

The dispersion (solution) comprises the above-mentioned polyolefin, other substances and a solvent. The solvent is determined in consideration of the solubility and boiling point of the polyolefin and other substances used. The solvent used in the present invention is not particularly limited, but preferred examples include aromatic solvents such as benzene, toluene, xylene and mesitylene, hexane, heptane, n-octane, 2-ethylhexane,
Paraffins such as -ethylcyclohexane; and chlorinated hydrocarbons such as dichloromethane, trichloromethane, tetrachloromethane, trichloroethylene and tetrachloroethylene. The substance mixed with these solvents may be either soluble or insoluble in the solvent. From such a viewpoint, these mixtures are described as "dispersion (solution) liquid" in this specification. It is preferable that the polyolefin and the other resin are dissolved in the above-mentioned solvent, but the inorganic and organic additives are not dissolved but are often used as a dispersion.

The solid portion refers to a portion other than the solvent in the entire dispersion (solution), and the solid portion concentration refers to the ratio of the weight of the non-solvent to the weight of the whole mixture expressed as a percentage. Say. The solid concentration is determined by adding the dispersion (solution) to 13
It is measured by drying at 0 ° C. for 24 hours and measuring the weight before and after the drying. The solid concentration of the dispersion (solution) in the present invention is preferably 1 to 20% by weight, more preferably 3 to 15% by weight.

In forming the film, the ambient temperature at which the dispersion (solution) liquid is supplied during the film formation is not particularly limited, but is usually 30 ° C. or higher and a temperature at which the particles do not adhere to each other. Is set. Specifically, 30 to 15
A range of about 0 ° C, more preferably a range of 30 to 100 ° C is selected. The hot air should be set to a temperature and an air volume necessary to stably jet the fertilizer particles and maintain the above temperature. For these techniques, conventionally known techniques can be applied.

In the production method of the present invention, a film is formed on the surface of the granular fertilizer by the above-described method. In addition, a second layer can be formed at an arbitrary position. These specific examples have already been described above. For example, it is possible to coat wax or the like between the film and the granular fertilizer or on the surface of the film using a conventionally known adhesive solution.

The present invention relates to a polyolefin or petroleum wax having a relatively low molecular weight and a specific amount, and a polyolefin having a specific molecular weight and a relatively high molecular weight having a specific amount.
And that a coated fertilizer having a coating containing a specific amount of a specific organometallic complex surprisingly shows a great effect on solving problems such as mechanical strength, dissolution controllability, and decomposition of the coating. is there. For example, compared to the case where only conventionally known general-purpose polyethylene resin is included,
The degradability of the film shows surprisingly good performance. On the other hand, as compared with the case containing only a relatively low-molecular-weight polyolefin, it shows excellent mechanical strength and elution controllability.

The coated fertilizer of the present invention has excellent mechanical strength, controllability of dissolution, and decomposability of the film, so that it can be widely used as a fertilizer having sustained release. Particularly, since the film is excellent in decomposability, the load on the environment is small.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention and comparative examples will be specifically described below. In addition, the test in an Example and a comparative example was based on the following method. (1) Dissolution test 10 g of the coated fertilizer was immersed in 200 ml of deionized water, and stored in a thermostat at 25 ° C. The fertilizer components eluted in water after a certain period of time were measured for the concentration of nitrogen, phosphoric acid, potash and the like using a total agricultural soil analyzer ZA-II. For urea, the liquid was quantified by ultraviolet absorption spectrophotometry. The elution rate is expressed as a percentage of the eluted component relative to the fertilizer component contained in the original coated fertilizer. (2) Abrasion resistance test 2 kg of coated fertilizer and 30 kg of silica sand Nikko No. 4 (manufactured by Kawairon Mining Co., Ltd.) were put into a concrete mixer and rotated for 6 hours. A dissolution test is performed on each of the coated fertilizers before and after the test, and the results are expressed as a difference in the dissolution rate on the third day. The higher the value, the lower the abrasion resistance. (3) Decomposition test 60 g of coated fertilizer was mixed with 300 g of field soil, spread thinly in a frame without a bottom, and left outdoors. Among the coated fertilizers after 3 years, the ratio of the total amount of the coated fertilizer that did not maintain the original film shape at all was shown.

[0033]

Example 1 A coated fertilizer was manufactured using the jet apparatus shown in FIG. That is, polyethylene having a weight average molecular weight of 750 (trademark; Neowax LS, Yashara Chemical Co., Ltd.)
25 parts by weight, iron acetylacetone complex 0.0177
Parts by weight (0.5 × 1 based on the solid content of the dispersion (solution) liquid described below)
0 ^-6 mol / g) and nickel dibutyldithiocarbamate 0.0071 parts by weight (below dispersion (solvent) solution having a weight average molecular weight containing 0.2 × 10 ^-6 mol / g) by solid content criteria polyethylene 74000 (Trademark: Suntech M227
1, 900 parts by weight of tetrachloroethylene were added to 25 parts by weight of Asahi Kasei Kogyo Co., Ltd., and the mixture was heated and refluxed to the boiling point of the solvent to dissolve them. Further, 48 parts by weight of talc and 2 parts by weight of polyoxyethylene nonylphenyl ether (HLB value: 19.5) were added to this solution, and the mixture was sufficiently stirred to prepare a dispersion. Granular potassium phosphate nitrate (N, P ₂ O ₅ , K ₂₎ having an average particle size of 3.0 mm sieved at 2 to 4 mm
100 parts by weight of the O component (15% each) were charged into the jetting device, and hot air was blown to cause a stable jetting condition at a temperature of 70 ° C in the device. Next, of the above dispersion (solution) liquids, 1
00 parts by weight was supplied from the play nozzle to the jet apparatus by the liquid feed pump in 10 minutes. During this time, 7
The temperature of the hot air was adjusted to be 0 ± 2 ° C. After the supply of the liquid was completed, the hot air was switched to cold air, and when the temperature became 35 ° C. or less, the contents were taken out from the jet apparatus.

The produced coated fertilizer was 105 parts by weight, and it was found that almost all of the supplied solid matter was coated. Further, when the coated particles were cut and observed under a microscope, it was observed that a film was formed around the granular potassium phosphate nitrate. When only the film was separated and the amount and molecular weight of the polyethylene contained were measured by GPC, 25% by weight of polyethylene having a molecular weight of 74,000 and 25% by weight of polyethylene having a molecular weight of 750
% By weight. When iron and nickel in the film were measured by atomic absorption method, iron was 0.5 ×
It was found that 10 ⁻⁶ mol / g and nickel were contained at 0.2 × 10 ⁻⁶ mol / g.

Each physical property of the obtained coated fertilizer was evaluated, and the results are shown in Table 1. The obtained coated fertilizer is controlled in elution of the fertilizing component, is excellent in abrasion resistance, and is excellent in the decomposability of the film after use.

[0036]

Example 2 60 parts by weight of polyethylene having a weight average molecular weight of 1200 (trade name; High Wax 110P, manufactured by Mitsui Petrochemical Industries, Ltd.), iron acetylacetone complex 0.0
177 parts by weight (0.1% based on the solid content of the dispersion (solution) liquid described below).
5 × 10 ⁻⁶ mol / g) and 0.0071 parts by weight of nickel dibutyl dithiocarbamate (0.2 × 10 ⁻⁶ mol / g based on the solid content of the following dispersion (solution) liquid). 20 parts by weight of 74000 polyethylene (trade name; Suntech M2270, manufactured by Asahi Kasei Corporation) and 1900 parts by weight of tetrachloroethylene are added to 10 parts by weight of an ethylene / vinyl acetate copolymer, and the mixture is heated and refluxed to the boiling point of the solvent. These were dissolved. Further, 7 parts by weight of talc and 3 parts by weight of polyoxyethylene nonylphenyl ether (HLB value: 19.5) were added to the solution, and the mixture was sufficiently stirred to prepare a dispersion. 100 parts by weight of granular potassium nitrate potassium (N, P ₂ O ₅ , and K ₂ O components are each 15%) having an average particle diameter of 3.0 mm sieved at 2 to 4 mm are put into a jet apparatus, and hot air is blown. When the temperature inside the apparatus was 70 ° C., a stable jet state was generated. Next, 200 parts by weight of the dispersion (solution) was supplied to the jet device from the play nozzle by the liquid feed pump in 20 minutes. During this time, 70 ± 2
The temperature of the hot air was adjusted to be ℃. After the liquid supply,
The hot air was switched to cold air, and when the temperature became 35 ° C. or less, the contents were taken out of the jet device.

The amount of the coated fertilizer produced was 110 parts by weight, and it was found that almost all of the supplied solid matter was covered. Further, when the coated particles were cut and observed under a microscope, it was observed that a film was formed around the granular potassium phosphate nitrate. When only the film was fractionated and the amount and molecular weight of the polyethylene contained were measured by GPC, 20% by weight of polyethylene having a molecular weight of 74,000 and 6% of polyethylene having a molecular weight of 1200 were measured per film weight.
It was found to contain 0% by weight. When iron and nickel in the film were measured by the atomic absorption method, iron was 0.5%.
× 10 ^-6 mol / g, nickel is 0.2 × 10 ^-6 mol / g
Turned out to be included.

Each physical property of the obtained coated fertilizer was evaluated, and the results are shown in Table 1. The obtained coated fertilizer is controlled in elution of the fertilizing component, is excellent in abrasion resistance, and is excellent in the decomposability of the film after use.

[0039]

Example 3 Polyethylene having a weight average molecular weight of 3350
(Trademark: High Wax 210P, Mitsui Petrochemical Industries
25 parts by weight, iron acetylacetone complex 0.3
5 parts by weight (1.0 × based on the solid content of the dispersion (solution) liquid described below)
10^-6Mol / g) and nickel dibutyl dithiocarba
0.0071 parts by weight (solid form of the following dispersion (solution) liquid
0.2 × 10 on a minute basis^-6Mol / g)
Polyethylene with an amount of 50,000 (trademark; Suntech M6)
555, manufactured by Asahi Kasei Corporation) 20 parts by weight, ethylene
1900 parts by weight of tet for 10 parts by weight of vinyl acetate copolymer
Add lachloroethylene and heat reflux to the boiling point of the solvent.
To dissolve them. In addition, add
56 parts by weight, starch 5 parts by weight, polyoxyethylene noni
Phenyl ether (HLB value 19.5) 4 parts by weight
Then, the mixture was sufficiently stirred to prepare a dispersion. Sieve at 2-4mm
Granular ammonium phosphate potassium (N, P) having an average particle diameter of 3.0 mm_Two
O_Five, K _TwoO component is 15% each) 100 parts by weight
And the hot air is blown, and the temperature inside the device is stable at 70 ° C
A jet state. Next, the dispersion (solution) solution
160 parts by weight from the play nozzle by the liquid feed pump
It took 15 minutes to feed the jet device. During this time, the jet device
The temperature of the hot air was adjusted so as to be 70 ± 2 ° C. Liquid
After the supply is completed, the hot air is switched to the cool air, and the temperature becomes 35 ° C or less.
At this point, the contents were removed from the jet device.

The amount of the coated fertilizer produced was 108 parts by weight, and it was found that almost all of the supplied solid matter was covered. Further, when the coated particles were cut and observed under a microscope, it was observed that a film was formed around the granular potassium phosphate nitrate. When only the film was separated and the amount and molecular weight of the polyethylene contained were measured by GPC, 10% by weight of polyethylene having a molecular weight of 50,000 and 2% of polyethylene having a molecular weight of 3350 were measured per film weight.
It was found to contain 5% by weight. When the iron and nickel in the film were measured by the atomic absorption method, the iron was 1.0%.
× 10 ^-6 mol / g, nickel is 0.2 × 10 ^-6 mol / g
Turned out to be included.

Each physical property of the obtained coated fertilizer was evaluated, and the results are shown in Table 1. The obtained coated fertilizer is controlled in elution of the fertilizing component, is excellent in abrasion resistance, and is excellent in the decomposability of the film after use.

[0042]

Example 4 15 parts by weight of polyethylene having a weight average molecular weight of 6400 (trade name; High Wax 410P, manufactured by Mitsui Petrochemical Industries, Ltd.), iron acetylacetone complex 0.3
5 parts by weight (1.0 × based on the solid content of the dispersion (solution) liquid described below)
10 ^-6 mol / g) and 0.0071 parts by weight of nickel dibutyldithiocarbamate (0.2 × 10 ^-6 mol / g based on the solid content of the following dispersion (solution) liquid) having a weight average molecular weight of 50,000. Polyethylene (trademark; Suntech M6)
To 555, 10 parts by weight of Asahi Kasei Kogyo Co., Ltd., 1900 parts by weight of tetrachloroethylene was added, and the mixture was heated and refluxed to the boiling point of the solvent to dissolve them. Further, 67 parts by weight of talc, 5 parts by weight of starch, and polyoxyethylene nonylphenyl ether (HLB value 19.5) 3 were added to this solution.
A part by weight was added and the mixture was sufficiently stirred to prepare a dispersion. 2-4
100 parts by weight of granular potassium nitrate potassium phosphate (N, P ₂ O ₅ , and K ₂ O components are each 15%) having an average particle diameter of 3.0 mm sieved in 0.1 mm are injected into the jetting device, and hot air is blown into the device. Temperature of 7
At 0 ° C., a stable jet state occurred. Next, 160 parts by weight of the dispersion (solution) was supplied from the play nozzle to the jet apparatus by the liquid feed pump in 15 minutes. During this time, the temperature of the hot air was adjusted to 70 ± 2 ° C. in the jet device. After the supply of the liquid is completed, the hot air is switched to the cold air,
When the temperature became lower than or equal to ° C, the contents were taken out of the jet apparatus.

The amount of the coated fertilizer produced was 108 parts by weight, and it was found that almost all of the supplied solid matter was coated. Further, when the coated particles were cut and observed under a microscope, it was observed that a film was formed around the granular potassium phosphate nitrate. When only the film was fractionated and the amount and molecular weight of the polyethylene contained were measured by GPC, 10% by weight of polyethylene having a molecular weight of 50,000 and 1% of polyethylene having a molecular weight of 6400 were measured per film weight.
It was found to contain 5% by weight. When the iron and nickel in the film were measured by the atomic absorption method, the iron was 1.0%.
× 10 ^-6 mol / g, nickel is 0.2 × 10 ^-6 mol / g
Turned out to be included.

Each physical property of the obtained coated fertilizer was evaluated, and the results are shown in Table 1. The obtained coated fertilizer is controlled in elution of the fertilizing component, is excellent in abrasion resistance, and is excellent in the decomposability of the film after use.

[0045]

Comparative Example 1 A coated granular fertilizer was obtained in the same manner as in Example 1 except that polyethylene having a weight average molecular weight of 74000 was not used and 50 parts by weight of polyethylene having a weight average molecular weight of 750 was used. The produced coated fertilizer was 105 parts by weight, and it was found that almost all of the supplied solid content was covered. When the amount and molecular weight of polyethylene contained in the film were measured by GPC, the molecular weight was 750.
Was found to contain 50% by weight of polyethylene. When the iron and nickel in the film were measured by the atomic absorption method, it was found that iron was contained at 0.5 × 10 ^-6 mol / g and nickel was contained at 0.2 × 10 ^-6 mol / g.

The properties of the obtained coated fertilizer were evaluated, and the results are shown in Table 1. The resulting coated fertilizer has poor abrasion resistance.

[0047]

Comparative Example 2 A coated granular fertilizer was obtained in the same manner as in Example 1 except that polyethylene having a weight average molecular weight of 750 was not used and 50 parts by weight of polyethylene having a weight average molecular weight of 74000 was used. The produced coated fertilizer was 105 parts by weight, and it was found that almost all of the supplied solid content was covered. Further, when the coated particles were cut and observed under a microscope, it was observed that a film was formed around the granular potassium phosphate nitrate. Sort only the film,
When the amount and molecular weight of the polyethylene contained were measured by GPC, it was found that the polyethylene contained 50% by weight of polyethylene having a molecular weight of 74,000 per film weight. When iron and nickel in the film were measured by the atomic absorption method, iron was 0.5 × 10 ⁻⁶ mol / g, and nickel was 0.2 × 10 ⁶ mol / g.
It was found that the content was 10 ^-6 mol / g.

Each physical property of the obtained coated fertilizer was evaluated, and the results are shown in Table 1. The obtained coated fertilizer is insufficiently degradable.

[0049]

Comparative Example 3 A coated granular fertilizer was obtained in the same manner as in Example 1 except that no iron acetylacetone complex and nickel dibutyldithiocarbamate were used. The produced coated fertilizer was 105 parts by weight, and it was found that almost all of the supplied solid content was covered. Further, when the coated particles were cut and observed under a microscope, it was observed that a film was formed around the granular potassium phosphate nitrate. When only the film was separated and the amount and molecular weight of the polyethylene contained were measured by GPC, it was found that the film contained 25% by weight of polyethylene having a molecular weight of 74000 and 25% by weight of polyethylene having a molecular weight of 750 per film weight. Was.

The physical properties of the obtained coated fertilizer were evaluated, and the results are shown in Table 1. The obtained coated fertilizer is insufficient in both abrasion resistance and degradability.

[0051]

[Table 1]

[0052]

The coated fertilizer of the present invention has excellent mechanical strength,
Since it has dissolution controllability and film decomposability, it can be widely used as a fertilizer having sustained release. One of the major features of the present invention is that the load on the environment is small because the film has excellent decomposability.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of an example of a jet apparatus used in the production method of the present invention.

[Description of Signs] 1 blower 2 orifice 3 heater 4 liquid feed pump 5 spray nozzle 6 fertilizer input port 7 discharge port 8 fertilizer T1 thermometer T2 thermometer

Claims (2)

[Claims] 1. The surface of a granular fertilizer has a polyolefin and / or petroleum wax having a weight-average molecular weight of 300 to 10,000 and a weight-average molecular weight of more than 10,000, based on the total weight of the film. 5 to 60% by weight of polyolefin, and iron, cobalt, nickel, copper, manganese, silver, palladium, molybdenum,
One or more organometallic complexes selected from chromium, tungsten and cerium in an amount of 0.02 to 20 × 10 ^-6 mol / g;
A granular coated fertilizer which is coated with a film containing the fertilizer, and wherein the total weight of the film relative to the granular fertilizer is 1 to 50% by weight. 2. Using a tumbling or jetting apparatus, 10 to 90% by weight of a polyolefin having a weight average molecular weight of 300 to 10,000 and / or petroleum wax, and 5 to 50% of a polyolefin having a weight average molecular weight of more than 10,000. 6
0% by weight, iron, cobalt, nickel, copper, manganese,
Silver, palladium, molybdenum, chromium, tungsten,
One or more organometallic complexes selected from cerium,
0.02 to 20 × 10 ^-6 based on the total solid content of the dispersion (solution) liquid
The method for producing a coated fertilizer according to claim 1, wherein a film is formed on the surface of the granular fertilizer by a dispersion (solution) solution containing mol / g.