JP2000351686A - Granular agricultural/horticultural composition from biodegradable coating film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition by coating a granular fertilizer with coating film material(s) at low cost in a simple operation in terms of solvent used so as to enable fertilizer effect duration to be regulated and, after eluting fertilizer ingredient(s), allow the coating film(s) not to be persistent in soil through being disintegrated and decomposed by soil microorganisms, namely, allow the coating film(s) to vanish after crop cultivation period. SOLUTION: This composition is obtained by coating a granular fertilizer with a coating film material A singly or a mixture of the coating film material A and another coating film material B; wherein the coating film material A comprises a cyclic ester-modified cellulose ester, and the coating film material B comprises at least one kind selected from the group consisting of olefin polymers, olefin-contg. copolymers, polyvinylidene chloride, vinylidene chloride- contg. copolymers, diene-based polymers, waxes, petroleum resins, natural resins, cellulose acetate resins, polycaprolactone, and fat-and-oil and modified products thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a granular fertilizer coated with a degradable coating composed of a biodegradable cyclic ester-modified cellulose ester. The coating of the granular fertilizer used in the present invention is decomposed by soil microorganisms and does not ultimately remain in the soil. In addition, various auxiliaries or chemicals can be added to the coating to adjust the dissolution of the granular fertilizer.

[0002]

2. Description of the Related Art Conventionally, various fertilizers of the fertilizer-control type have been developed for the purpose of exerting a fertilizer effect according to the growth of a crop. In particular, many granular fertilizers in which the surface of the granular fertilizer is covered with a coating material are disclosed and commercially available. Tokuho 7
For example, as described in U.S. Pat. No. 3,505,505, US Pat. No. 3,295,950, Japanese Patent Publication No. 40-2892.
No. 7, Japanese Patent Publication No. 44-28457, British Patent No. 815829, Japanese Patent Publication No. 37-15832, Japanese Patent Publication No. 42-13681, etc., have proposed various fertilizers of the fertilizer-control type. . However, it is taught that it is difficult to control the dissolution rate of the fertilizer component in any of these fertilizers of the fertilizer effect-control type.

On the other hand, in Japanese Patent Publication Nos. 60-1952 and 60-3040, a coating material containing a polyolefin as a main component is used. When coating the surface of the granular fertilizer, the coating material is applied to the granular fertilizer. A method for forming a film by spraying a solution of the above and simultaneously drying with a hot air stream is disclosed. As a feature of this technology, it is taught that it is possible to adjust the dissolution rate of the granular fertilizer,
And the above-mentioned method of forming a film on the surface of granular fertilizer is widely used in practice. Further, in JP-B-60-3040 and JP-A-55-1672, etc., the dissolution control function is maintained by dispersing an inorganic powder such as talc and sulfur in a coating film of a polyolefin resin, etc. In addition, it is shown that the disintegration and decomposition of the residual film after elution are promoted.

[0004] In these particulate fertilizers that have been conventionally proposed, the coating does not disintegrate or decompose, and remains in the soil without decomposing even when disintegrated, and the growth of crops, the soil environment and the water used in the surroundings of the fields.・ There is a danger of causing pollution in rivers. For these reasons, there is a strong demand for granular fertilizers in which the coating has degradability and the fertilization period can be adjusted. In such a degradable coating, degradability means that it is decomposed by light, oxygen, microorganisms, etc., and it is difficult to control the elution rate of the fertilizer component, especially in the conventional coated granular fertilizer. There was a drawback that the fertilization period was easily affected by the environment such as weather and soil. It has also been pointed out that the film after elution of the fertilizer component remains in the soil for a long time without being decomposed. Also, many attempts have been made to apply biodegradable resins. For example, JP-A-7-33576 discloses a combination of polycaprolactone, polylactic acid, or a combination of an aliphatic polyester compound with a cellulose derivative, low-molecular-weight polyethylene, paraffin, or the like. Has been described. However, in this case, the melting point of the polycaprolactone used is 60 ° C., which may cause blocking during transportation or storage of the product. Further, polylactic acid and aliphatic polyester have a low solubility in a solvent, so that practically difficult ones have not yet been found. Japanese Patent Publication No. 7-505 also discloses a granular fertilizer coated with polycaprolactone. Further, in Japanese Patent Application Laid-Open No. 11-116371, since low-substituted cellulose acetate having low solubility is used, trichlene or tetrahydrofuran (THF) is used as a solvent used for coating the granular fertilizer. Therefore, there was a problem in operability and cost with respect to the solvent.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a fertilizer which can be easily operated at a low cost with respect to a solvent when coated on a granular fertilizer. After elution, the coating is disintegrated and decomposed by soil microorganisms and does not remain in the soil, and the residual component amount after the cultivation period of the crop is reduced. It is to be.

[0006]

In order to produce a granular fertilizer coated with a degradable film whose decomposability is adjustable and the fertilization time is adjustable, the present inventors have proposed a method for dissolving a solvent in a coating. The present inventors have made intensive studies on the selection of a coating material in consideration of the price of the solvent and the solvent, and have reached the present invention.

That is, a first aspect of the present invention is that the surface of a granular fertilizer is coated with the coating material A alone or a mixture of the coating material A and the coating material B, and the coating material A is made of a cyclic ester-modified cellulose ester, The coating material B is an olefin polymer,
From the group consisting of copolymers containing olefins, vinylidene chloride polymers, copolymers containing vinylidene chloride, diene polymers, waxes, petroleum resins, natural resins, cellulose acetate resins, polycaprolactone, oils and fats and modified products thereof A granular agricultural and horticultural composition comprising at least one selected from the group consisting of: A second aspect of the first aspect of the invention is characterized in that the cyclic ester-modified cellulose ester comprises a cellulose ester derivative obtained by subjecting a cyclic ester to ring-opening graft polymerization on a cellulose ester having a hydroxyl group. A particulate agricultural horticultural composition is provided. A third aspect of the present invention is characterized in that the cellulose ester having a hydroxyl group is cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, or a mixture thereof.
2. A granular agricultural and horticultural composition according to item 1. A fourth aspect of the present invention provides the granular agricultural and horticultural composition according to the second aspect, wherein the cyclic ester is ε-caprolactone. A fifth aspect of the present invention provides the granular agricultural and horticultural composition according to the first aspect of the present invention, wherein the coating material B is polycaprolactone, cellulose acetate, or a mixture thereof. A sixth aspect of the present invention provides the granular agricultural and horticultural composition according to claim 1, further comprising an inorganic filler and / or a resin additive. Seventh of the present invention
Provides the granular agricultural and horticultural composition according to the sixth aspect of the present invention, wherein the inorganic filler is talc, calcium carbonate, or a mixture thereof.

[0008] The granular agricultural and horticultural composition of the present invention is obtained by spraying a solution comprising the above-mentioned coating material onto granular fertilizer, and simultaneously applying a high-speed hot air stream to the position to instantaneously dry and coat the composition. A granular fertilizer characterized in that the coating has degradability and the fertilization period can be adjusted.

First, the cyclic ester-modified cellulose ester used for the coating material A of the present invention will be described.
Cyclic ester modified cellulose ester according to the present invention,
It is obtained by graft-modifying a cellulose ester having a hydroxyl group by ring-opening polymerization of a cyclic ester. The cellulose ester having a hydroxyl group is obtained by leaving a part of the hydroxyl group of the cellulose esterified with a fatty acid or an inorganic acid, for example, cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, or cellulose acetate phthalate. And hybrid esters such as cellulose nitrate and cellulose nitrate acetate. These cellulose esters can be used alone or in combination of two or more. Of these, cellulose acetate, cellulose acetate propionate,
Esters with fatty acids such as cellulose acetate butyrate are preferred, and cellulose acetate is particularly useful. In the following, description will be made mainly with esters of fatty acids (fatty acid cellulose esters) as typical examples.

The average ester bond composed of the fatty acid and the hydroxyl group of the glucose unit of cellulose is 1 to 2.9.
, That is, the degree of substitution is preferably from 1 to 2.9, and thus the residual hydroxyl group is preferably from 0.1 to 2 on average, and particularly preferably from 0.2 to 2 on average.
0.9 is preferred. When the substitution degree is less than the above range,
When coated with the obtained cyclic ester-modified cellulose ester, the water resistance of the surface of the granular fertilizer decreases, and if it exceeds the above range, not only compatibility with other components, melt fluidity, but also biodegradability significantly decreases. I do. The degree of substitution DS of the cellulose ester is described by taking cellulose acetate as an example, and the bound acetic acid% (degree of acetylation) is represented by X, Y = X / 10
When it is set to 0, it can be calculated by the following equation. Degree of substitution DS = (162 × Y) / (60−42 × Y)

The cyclic ester used for reacting with the hydroxyl group of the above-mentioned cellulose ester is not particularly limited as long as it can undergo ring-opening polymerization. For example, β-propiolactone, δ-valerolactone , Ε-
Caprolactone, α, α-dimethyl-β-propiolactone, β-ethyl-δ-valerolactone, α-methyllactone, β-methyl-ε-caprolactone, γ-methyl-ε-caprolactone, 3,3,5- Trimethyl-ε-
Examples include lactones such as caprolactone, 3,5,5-trimethyl-ε-caprolactone, and enantholactone, and cyclic esters such as glycolide and lactide. The cyclic ester according to the present invention is not limited to a single type, but may be a combination of a plurality of the above various types. As the cyclic ester, ε-caprolactone, which is particularly easily available industrially, is relatively inexpensive, and has excellent compatibility with the fatty acid cellulose ester according to the present invention, such as cellulose acetate, is particularly suitable.

There are no particular restrictions on the charge ratio between the fatty acid cellulose ester having a hydroxyl group and the cyclic ester for obtaining the cyclic ester-modified fatty acid cellulose ester,
Fatty acid cellulose ester having hydroxyl group 1-85wt
%, The ratio of the cyclic ester is preferably 99 to 15 wt% (the total of both is 100 wt%). If the charged ratio of the fatty acid cellulose ester having a hydroxyl group exceeds 85% by weight, the viscosity of the reaction system becomes extremely high, making it difficult to handle. Conversely, if it is less than 1 wt%, the productivity will decrease. When flexibility is required, it is preferable to increase the charging ratio of the cyclic ester. When the viscosity is too high to handle easily, an organic solvent having no active hydrogen having good compatibility with fatty acid cellulose ester and cyclic ester or a reactive polyhydric alcohol is added as a third component. Can be reduced to facilitate the reaction.

As the catalyst used for the reaction of graft-polymerizing a cyclic ester, particularly a lactone, to a fatty acid cellulose ester having a hydroxyl group, a catalyst usually used for a ring-opening reaction of a cyclic ester, for example, an alkali metal such as sodium, potassium or the like, Derivatives such as alkoxides, alkylaluminums and derivatives thereof represented by triethylaluminum, alkoxytitanium compounds represented by tetrabutyl titanate, organic metals or metal complexes such as tin octylate, dibutyltin laurylate, and metal halides such as organic tin Is mentioned. The preferred catalyst used for producing the cyclic ester-modified fatty acid cellulose ester according to the present invention is tin octylate.

In order to obtain the above-mentioned cyclic ester-modified fatty acid cellulose ester, which is the graft polymer according to the present invention, a conventional reactor equipped with a stirrer and a reflux condenser (with a drying tube) is used. A machine is preferably used as the reactor. The polymerization temperature for obtaining the graft polymer according to the present invention is usually preferably the temperature applied to ring-opening polymerization of a cyclic ester, and is preferably 100 to 210 ° C.
Is preferred. Further, the polymerization reaction time, the type of each of the fatty acid cellulose ester having a hydroxyl group and the cyclic ester, the charging ratio, the type and amount of the catalyst, the reaction temperature, further varies depending on the reaction apparatus, is not particularly limited, Preferably, it is 1 to 8 hours.

In obtaining the above graft polymer,
It is desirable that each raw material, nitrogen, reactor, and the like used in the polymerization reaction be sufficiently dried. Further, the water content of the reaction system is 0.1 wt% or less, preferably 0.01 wt%.
Or less, more preferably 0.001 wt% or less.

The graft polymer thus obtained,
That is, the molecular weight of the cyclic ester-modified fatty acid cellulose ester depends on the molecular weight of the raw material hydroxyl group-containing fatty acid cellulose ester and the type of the cyclic ester to be grafted, but the weight average molecular weight is preferably in the range of 200,000 to 2,000,000. Preferably, 300,000 to 1,000,000 is more preferable. When the weight average molecular weight of the graft polymer is less than 200,000, when the weight average molecular weight of the original fatty acid cellulose ester is, for example, 1570,000 of cellulose acetate, the amount of the added cyclic ester is small, and The flexibility of the coating material A obtained from the polymer tends to be insufficient. On the other hand, if it exceeds 2,000,000, the viscosity of the graft polymer is too high, and a coating problem is likely to occur.

The average graft polymer obtained by the polymerization reaction at the charged ratio of the fatty acid cellulose ester having a hydroxyl group and the cyclic ester has a cyclic ester such as ε-caprolactone of 2 to 50 mol per residual hydroxyl group in the glucose unit. Is preferably 3 to 30 mol, and most preferably a compound having a structure formed by addition polymerization of 5 to 20 mol.

The internal plasticizing effect of the fatty acid cellulose ester by adding a cyclic ester can lower the melting temperature of the product and increase the thermal decomposition temperature.
In this way, it is possible to coat with a device used for ordinary thermoplastic resin coating without adding a large amount of plasticizer. Further, since the coating internally plasticized with the cyclic ester according to the present invention has no migration property, even if it is left under high temperature and high humidity while being in contact with other molded products, there is no danger of corroding other components.

The cyclic ester-modified fatty acid cellulose ester used in the present invention may be used alone, provided that it contains the cyclic ester-modified fatty acid cellulose ester.
Composition containing a plurality of cyclic ester modified fatty acid cellulose esters having different degrees of substitution (manufactured from a mixture of a plurality of fatty acid cellulose esters having different degrees of substitution)
It may be constituted as. Such a composition may contain another cellulose ester such as a highly substituted cellulose ester as a coating material B described later. The degree of substitution of the highly substituted cellulose ester includes a highly substituted cellulose ester having poor biodegradability (for example, a cellulose ester having a degree of substitution of 2.2 or more, more preferably 2.4 or more). In addition, the preferred highly substituted cellulose ester often has the same or similar substituent, particularly the same substituent, as the above-mentioned fatty acid cellulose ester having a hydroxyl group. The same or similar substituent, when the fatty acid cellulose ester is cellulose acetate,
Organic acid ester residues having about 1 to 4 carbon atoms are included. A feature of the composition containing a plurality of cyclic ester-modified fatty acid cellulose esters having different degrees of substitution is that even if the content of the cyclic ester-modified fatty acid cellulose ester is small, the biodegradability of the coating material can be enhanced. . The content of the cyclic ester-modified fatty acid cellulose ester is 10% by weight or more, preferably 10 to 90% by weight, more preferably 10 to 75% by weight of the whole fatty acid cellulose ester and its cyclic ester modified product (graft polymer).
% By weight (for example, 10 to 50% by weight). When the content of the cyclic ester-modified fatty acid cellulose ester is 10
When the content is not less than% by weight, the biodegradability of cellulose ester having poor biodegradability can be dramatically improved. In addition, as the graft polymer content of the low-substituted cellulose ester increases, the cellulose ester composition can be biodegraded in a short time. The mechanism of biodegradation in such a composition is not clear, but by adding a small amount of the cyclic ester-modified fatty acid cellulose ester, a microorganism that originally does not have degradability to a highly substituted cellulose ester is acclimated, and As a result, it is assumed that the cellulose ester having a high degree of substitution is also decomposed. In addition, the cellulose ester as a raw material can be produced by a conventional method regardless of the degree of substitution. Also, the degree of substitution of the cellulose ester,
In the reaction of cellulose with an organic acid or acid anhydride,
The degree of substitution may be adjusted in a single-stage reaction, or after a cellulose ester having a high degree of substitution (for example, trisubstituted product) is once produced, the degree of substitution may be adjusted by hydrolysis.

The substance used as the coating material B in the present invention includes olefin polymers, copolymers containing olefins, vinylidene chloride polymers, copolymers containing vinylidene chloride, diene polymers, waxes, petroleum resins, One or more substances selected from the group consisting of natural resins, cellulose acetate resins, polycaprolactone, fats and oils, and modified products thereof.

The above-mentioned olefin polymer includes polyethylene, polypropylene, ethylene-propylene copolymer,
Polybutene, butene-ethylene copolymer, butene-propylene copolymer, polystyrene, etc., and copolymers containing olefins include ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid Ester copolymer, ethylene / methacrylic acid copolymer,
Ethylene / methacrylic acid ester copolymer, ethylene / carbon monoxide copolymer, ethylene / vinyl acetate / carbon monoxide copolymer and the like. The copolymer containing vinylidene chloride is a vinylidene chloride-vinyl chloride copolymer,
The diene polymer includes butadiene polymer, isoprene polymer, chloroprene polymer, butadiene / styrene copolymer, EPDM polymer, styrene / isoprene copolymer, and the like. The waxes are beeswax, wood wax, paraffin and the like, and the natural resins are natural rubber, rosin and the like. The cellulose acetate resin is a diacetate having an average degree of substitution of 2.5 and a triacetate having an average degree of substitution of 2.9. Polycaprolactone is a polyester formed by ring-opening addition polymerization of ε-caprolactone, and has a molecular weight of 10,000 or more, preferably 50,000 to 100,000. Fats and oils and modified products thereof include hardened oils and solid fatty acids. And metal salts.

The weight percentage of the coating material of the present invention with respect to the coated granular material, that is, the coating ratio is preferably 2 to 20%. The coating material A is 10 to 100%, preferably 5 to 100% (weight) in total of the coating material A and the coating material B.
It is used in the range of 0 to 100%, and the coating B is also 0 to 9%.
0% (weight), preferably in the range of 0 to 50%.

The coating material of the present invention uses a third coating material component which can be mixed if necessary. Third such
The coating material components (represented as coating material C in Table 1 of Examples) include resin additives such as plasticizers, surfactants as dissolution regulators, talc as an insoluble filler, calcium carbonate, and metal oxides. And the like. These third coating material components need to be uniformly dispersed.
If it is not uniform, some of the fine particles will be offset and the continuous phase of the coating material will be impaired, and the effect of the coating will be lost. The addition amount of talc, calcium carbonate, metal oxide, or a mixture thereof as a filler to 100 parts by weight of the coating material A alone or 100 parts by weight of the mixture of the coating material A and the coating material B is 0 to 2
00 parts by weight, preferably 10 to 150 parts by weight, more preferably 20 to 100 parts by weight. If the amount is more than the above range, pores tend to be formed in the coating, and the elution of fertilizer cannot be controlled.

In the present invention, a fourth coating material component is further used as necessary. Examples of such a fourth coating material component include a photodegradation accelerator and a biodegradation accelerator, an elution regulator, a cellulose powder, and the like. These components can be uniformly dispersed and used.

Examples of the photolysis accelerator include benzophenones such as benzoins, benzoin alkyl ethers, benzophenone, and 4,4'-bis (dimethylamino) benzophenone and derivatives thereof; acetophenone,
Acetophenones such as α, α-diethoxyacetophenone and derivatives thereof; quinones; thioxanthones; photoexciting materials such as phthalocyanine, anatase-type titanium oxide, ethylene-carbon monoxide copolymer, sensitization of aromatic ketones with metal salts And the like. One or more of these photolysis accelerators can be used. When a photodegradation accelerator is used, the cellulose ester can be photodecomposed. Therefore, biodegradability can be enhanced in combination with photodegradability.

Examples of the biodegradation accelerator include oxo acids (for example, oxo acids having about 2 to 6 carbon atoms such as glycolic acid, lactic acid, citric acid, tartaric acid, and malic acid), saturated dicarboxylic acids (for example, oxalic acid). Organic acids such as malonic acid, succinic acid, succinic anhydride, glutaric acid, etc. and low saturated dicarboxylic acids having about 2 to 6 carbon atoms); these organic acids and 1 to 4 carbon atoms
Lower alkyl esters with alcohols are included. Preferred biodegradation accelerators include organic acids having about 2 to 6 carbon atoms, such as citric acid, tartaric acid, and malic acid. One or more of these biodegradation accelerators can be used.

As the biodegradation promoter, biodegradation enzymes,
For example, hydrolytic enzymes such as lipase, cellulase, and esterase are also included. The biodegradable enzyme can be used by suspending or dispersing it in a solvent. The photodegradation promoter and the biodegradation promoter can be used in combination.
It is also possible to mix a cellulose powder to prevent aggregation of the coated granules.

In the present invention, the coating material is dissolved or dispersed in a solvent, kept at a high temperature, added to the surface of the granular fertilizer in the form of a spray, and simultaneously dried by applying a high-speed hot air stream to the position. By doing so, a granular fertilizer is obtained.
As the solvent, cyclohexanone, methyl formate, methyl acetate, THF, dioxane, acetone and the like can be used because low-substituted cellulose acetate disclosed in JP-A-11-116371 has poor solvent solubility. However, none of them has a moderate boiling point (70 to 90 ° C.) with good operability. For example, THF
Has a slightly lower boiling point of 65 ° C. and is expensive. On the other hand, cyclic ester-modified cellulose esters such as lactone-modified cellulose esters are dissolved in ethyl acetate and 2-butanone (MEK) as well as the above-mentioned solvents. Ethyl acetate and 2-butanone have a boiling point of around 80 ° C. and are less expensive than THF.

[0029]

The present invention will be specifically described below with reference to examples and comparative examples. Parts and% indicate parts by weight and% by weight, respectively, unless otherwise specified. (1) Synthesis of Cyclic Ester-Modified Cellulose Ester Cellulose acetate which had been sufficiently dried in advance in a sufficiently dried reactor equipped with a stirrer, a thermometer and a reflux condenser under a dry nitrogen atmosphere and 50 parts of ε-caprolactone. (Manufactured by Daicel Chemical, degree of acetylation 55.2%, degree of substitution 2.43) 100
Then, 0.12 parts of tin octylate was charged, and the reaction was continued for 3 hours. Thus, a slightly yellow transparent caprolactone-modified cellulose acetate [I] was obtained. The intrinsic viscosity of the graft polymer at 50 ° C. was determined using acetone [η].
= 0.75 l / g. The obtained caprolactone-modified cellulose acetate [I] was used as coating material A.

(2) Method and Apparatus for Producing Granular Agricultural and Horticultural Composition FIG. 1 shows a preferred example of the apparatus of the present invention. Spout tower 1
Has a tower diameter of 200 mm, a height of 180 mm, and an air ejection diameter of 42 mm
And has a fertilizer input port 2 and an exhaust gas outlet 3. The jet air is sent from the blower 10 and reaches the jet tower via the orifice flow meter 9 and the heat exchanger 8. The flow rate is controlled by a flow meter 9, the temperature is controlled by a heat exchanger 8, and the exhaust gas is guided from the exhaust gas outlet 3 to the outside of the tower. The granular fertilizer to be subjected to the coating treatment is injected from the fertilizer input port 2 while passing through a predetermined hot air to form a jet. In the coating treatment, the coating liquid containing the fatty acid cellulose ester derivative is sprayed through the liquid nozzle 4 toward the jet after the coating particle temperature reaches a predetermined temperature. The coating liquid is prepared by putting a predetermined amount of the coating material and the solvent in the liquid tank 11 and stirring the mixture near the boiling point of the solvent. The supply of the coating liquid is sent to the nozzle 4 by the pump 5, and the system is kept sufficiently warm to maintain the temperature. When a predetermined coating liquid is supplied, the pump 5 is stopped, and then the blower 10 is stopped. The coated fertilizer is removed from the outlet 7. 6 is a valp. In FIG. 1, T ₁ , T ₂ and T ₃ are thermometers, and SL is steam. In each of the examples and comparative examples, the granular fertilizer was coated while maintaining the following basic conditions.

Liquid nozzle: 0.8 mm opening, full-con type Hot air volume: 4 m ³ / min Hot air temperature: 100 ° C. Type of fertilizer: Phosphorus ammonium nitrate with 5-7 mesh Fertilizer input amount: 5 kg Coating solution concentration: 5% by weight of solid content Liquid supply amount: 0.5 kg / min Coating time: 10 minutes Coverage (to fertilizer): 5.5% by weight (including surfactant) Solvent: ethyl acetate or 2-butanone Coating material B PCL: Daicel Polycaprolactone [PCL-H7] diacetate manufactured by Chemical Industry Co., Ltd .: Daicel Chemical Industry Co., Ltd. [degree of acetylation 55.0, viscosity of 6% acetone solution 1
00cps] Coating material C (filler added to coating material A and coating material B):
talc

(3) Coating Composition and Biodegradation Test Coated phosphoric acid nitrates having various coating compositions shown in Table 1 were manufactured by the above-described manufacturing method. Thereafter, 50 coated samples of the present example were cut on two sides one by one, left in water to remove the fertilizer therein, dried and finely pulverized, and then subjected to JIS K6950 (activated sludge). Degradation rate was determined by aerobic biodegradation test method). The activated sludge used was the sludge returned from the Himeji Sewage Treatment Plant. Examples 1 to 6
Table 1 shows the results.

[0033]

[Table 1]

[0034]

EFFECT OF THE INVENTION The granular agricultural horticultural composition of the present invention has good solvent operability at the time of forming a film, and the obtained granular agricultural horticultural composition can control the duration of fertilizing effect. Is decomposed and decomposed by soil microorganisms and does not remain in the soil. Furthermore, the amount of residual components after the cultivation period of the crop disappears due to the disintegration and decomposition of the film, which has the effect of facilitating fertilizer management.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of an apparatus suitable for manufacturing an invention.

[Brief description of reference numerals]

1 jet column, 2 fertilizer inlet, 3 gas ejection port, 4-fluid nozzle, 5 pump, 6 valves, 7 extraction port, 8 heat exchanger, 9 orifice meter, 10 a blower, 11 tank, T _1, T ₂ , T ₃ thermometer, SL steam

Claims (7)

[Claims] The surface of a granular fertilizer is coated with a coating material A alone or a mixture of a coating material A and a coating material B.
Is composed of a cyclic ester modified cellulose ester, the coating material B is an olefin polymer, a copolymer containing olefin,
Vinylidene chloride polymer, copolymer containing vinylidene chloride, diene polymer, waxes, petroleum resin, natural resin, cellulose acetate resin, polycaprolactone, oil and fats and modified products thereof. A granular agricultural and horticultural composition, comprising: 2. The granular agricultural and horticultural product according to claim 1, wherein the cyclic ester-modified cellulose ester comprises a cellulose ester derivative obtained by ring-opening graft polymerization of a cyclic ester with a hydroxyl group-containing cellulose ester. Composition. 3. A cellulose ester having a hydroxyl group,
The granular agricultural and horticultural composition according to claim 2, wherein the composition is cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, or a mixture thereof. 4. The granular agricultural and horticultural composition according to claim 2, wherein the cyclic ester is ε-caprolactone. 5. The granular agricultural and horticultural composition according to claim 1, wherein the coating material B is polycaprolactone, cellulose acetate, or a mixture thereof. 6. The granular agricultural and horticultural composition according to claim 1, further comprising an inorganic filler and / or a resin additive. 7. The granular agricultural and horticultural composition according to claim 6, wherein the inorganic filler is talc, calcium carbonate or a mixture thereof.