WO2019117650A1 - Controlled release fertilizer - Google Patents

Abstract

The present invention relates to a controlled release fertilizer comprising: a photodegradable capsule comprising a binder resin inclusive of polyolefin and ethylene vinyl acetate copolymer; and a photocatalyst composite in which a (co)polymer including at least one repeat unit selected from an ethylenic repeat unit and a vinyl acetate repeat unit is coupled to the surface or inside of an aggregate of inorganic microparticles; and a fertilizer contained within a space surrounded by the photodegradable capsule.

Description

 Title of the Invention

 Controlled release fertilizer

 TECHNICAL FIELD

 Cross-reference with related application (s)

 This application claims the benefit of priority based on Korean Patent Application No. 10-2017-0172272, dated December 14, 2017, and Korean Patent Application No. 10-2018-0160288, dated December 12, 2018, The entire contents of which are incorporated herein by reference.

 The present invention relates to a dissolution-controlled fertilizer, and more particularly, to a dissolution-control-type fertilizer having a high stability against moisture, a solid structure, and an easily controlling dissolution period of a fertilizer and realizing excellent photodissociation efficiency.

 TECHNICAL BACKGROUND OF THE INVENTION

 Various leaching control type fertilizers have been developed for the purpose of harvesting fertilizer (SESE) or manifesting the effect of fertilizer according to the growth of plants.

 Controlled release fertilizers (CRFs), such as nitrogen, phosphorus and potassium, are slowly supplied to crops for a long time. Conventional fertilizers that are sprayed in water or sprayed in powder form usually do not last for more than 20 days once sprayed. This is due to the fact that the crops are not able to sustain the fertilizer composition because they are washed away in the rain or deeply penetrated into the soil.

In order to compensate for these disadvantages of general fertilizer, the controlled release type fertilizer lowers the release rate of the fertilizer component with the polymer capsules so that it is released over a long period of time. The polymer capsules are made of olefin resin, urethane resin, latex, acrylic resin, etc. After the water vapor penetrates through the capsules, the fertilizer components are melted, and the capsules are permeated and released by the osmotic principle. The penetration rate of water and fertilizer components varies depending on the ingredients and the thickness of the capsules. This can be used to control the rate at which the fertilizer component is released. The period of release of the fertilizer component from the capsule can be adjusted from a minimum of 30 days to a maximum of 2 years. However, after release of the fertilizer, 2019/117650 1 ^» (: 1 ^ 1 {2018/015866

There is a problem that remains in the river.

In order to solve this problem, attempts have been made to use a biodegradable polymer as a capsule material. Since the biodegradable polymer is rapidly permeated by water and decomposed by microorganisms within ₁ month to ₆ months, It was not suitable for use in controlled-release fertilizers that had to be released over _two years.

 DISCLOSURE OF THE INVENTION

 [Problem to be solved]

The present invention provides a controlled-release fertilizer having a high stability against water and a solid structure, capable of easily controlling the dissolution period of ₁₀ of the fertilizer, and capable of realizing excellent photodegradation efficiency.

 MEANS FOR SOLVING THE PROBLEMS

In the present specification, polyolefin and ethylene vinyl acetate binder resin containing the copolymer, and (co) including a repeating unit selected at least _one from the ₁₅ group consisting of ethylene repeating units and vinyl acetate repeating units of the polymer, the surface of the agglomerates of the inorganic fine particles Or a photocatalytic composite comprising a photocatalyst composite and a photocatalytic composite, the photocatalytic composite comprising a photocatalytic composite and a photocatalytic composite, the photocatalytic composite comprising:

About dissolution-controlled fertilizer according to the specific implementation of the invention will be hereinafter described in detail than _20. In the present specification, the (co) polymer is meant to include both a polymer and a copolymer.

According to one embodiment of the ₂₅ invention, the polyolefin and ethylene vinyl acetate binder resin, including co-polymer; of and ethylene repeating units and vinyl including repeating units of at least _one member selected from the group consisting of acetate repeating units (co) polymer, the inorganic fine particles the photocatalyst composite material bonded to the surface or interior of the aggregates; a dissolution-controlled fertilizer comprising the fertilizer contained in the space ₃₀ surrounded by the photodegradable capsules and the capsules containing photodegradable can be provided. 2019/117650 1 »(: 1 ^ 1 {2018/015866

The present inventors have found that a release-controlled fertilizer having a photocatalytic capsule containing the above-described photocatalytic composite together with a binder resin containing a polyolefin and an ethylene vinyl acetate copolymer has a high stability against moisture and a rigid structure and can easily control the duration of a fertilizer And it is possible to realize excellent photodecomposition efficiency.

 The above-mentioned dissolution-controlled fertilizer is also characterized in that the photocatalytic composite is uniformly dispersed in the above-mentioned binder resin. Specifically, as the (co) polymer containing at least one repeating unit selected from the group consisting of the ethylene repeating unit and the vinyl acetate repeating unit is bound to the surface or inside of the agglomerate of the inorganic fine particles, Or the inorganic fine particles can be uniformly dispersed in the leaching control type fertilizer, so that the agglomerate of the inorganic fine particles can have a large particle size.

 The agglomerates of the inorganic fine particles are uniformly dispersed in the binder resin while having a small particle size, so that photodegradation reaction is locally caused when the photodegradable capsules are exposed to light, thereby preventing degradation of photodecomposition efficiency So that the photodegradable capsules do not remain in the soil.

 This may be due to the incorporation of a (co) polymer containing one or more repeating units selected from the group consisting of ethylene repeating units and vinyl acetate repeating units on the surface or inside of the aggregate of the inorganic fine particles. That is, as the (co) polymer is bonded to the surface or inside of the agglomerate of the inorganic fine particles, the growth of agglomerates of the inorganic fine grains can be controlled, and the compatibility of the inorganic fine particles with the binder resin So that the photocatalytic composite can be uniformly distributed in the binder resin.

As described above, the lanyard-controlled fertilizer can realize excellent photodegradation efficiency. More specifically, when light of a wavelength of 300 ₁₁₁₁₁ to 800 is irradiated at a strength of 400 for 224 hours, the weight of the photodegradable capsule The decomposition ratio of the binder resin to be derived may be _40% or more, or _50% or more. The inorganic fine particles may serve as a photocatalyst. The lance-controlled fertilizer of the embodiment is characterized in that the photocatalytic composite is uniformly dispersed in the binder resin in order to solve the problem that the photodegradable capsule remains in the soil. Since the photocatalytic complex acts as a catalyst only during the light receiving period, the photocatalytic capsule is slowly decomposed while the photocatalytic capsule is not decomposed while the fertilizer is released in the soil where the light is blocked. When the leaching control type fertilizer is exposed to the topsoil by plowing or the like, the photodegradable capsule may be decomposed by light.

_10, the inorganic fine particle may comprise primary particles having a cross-sectional diameter of ₅ to _{50 nm.} Cross-sectional diameter of the primary particles of said inorganic fine particles are conventionally known method, for example, verification by the _TEM image and, _BET Measurement and so on.

If the cross-sectional diameter of the primary particles is too ₁₅ less contained in the inorganic fine particle, the degree of crystallization can be the photocatalytic efficiency is lowered away. Further, the cross-sectional diameter of the primary particles is too large, the photocatalytic particles contained in the inorganic fine particle The specific surface area is lowered and the photocatalytic efficiency may be lowered.

On the other hand, the agglomerates of the inorganic fine particles contained in the dissolution-controlled fertilizer of the above embodiment may have a particle size not so large. Specifically,

The cross-sectional diameter and the diameter of the agglomerate of the inorganic fine particles can be confirmed by a commonly known method, for example, _SEM or _TEM microtome.

The cross-sectional diameter or overall size of the aggregates of the inorganic fine particles ₂₅ is too large, there is a localized photolytic reaction in the photodegradable capsule can be up or decrease the efficiency of photolysis reaction, due to the inefficient photolysis reaction entire photodegradable capsule It may not be decomposed and residues may remain.

Specific examples of the inorganic fine particles include titanium dioxide ( _TiO2), zinc oxide ( _ZnO), and mixtures thereof.

30 \ ¥ 0 2019/117650 1 »<171012018/015866

Meanwhile, the binder resin may be a main material forming the outer structure of the photodegradable capsule, and as described above, the binder resin may include a polyolefin and an ethylene vinyl acetate copolymer.

 Examples of the polyolefin include, but are not limited to, high density or low density polyethylene, linear low density polyethylene, polypropylene, ethylene-propylene copolymer, polybutene, butene-ethylene copolymer, butene- Mixtures thereof, or copolymers of two or more thereof.

The ethylene vinyl acetate copolymer contained in the binder resin is not particularly limited. For example, an ethylene vinyl acetate copolymer containing 1 to 45% by weight of vinyl acetate repeating units may be used. The ethylene vinyl acetate copolymer has a melt index of 0.5 / 10 ₁₁ to 5.0 / 10 ₁₁ or 1.0 / 10 ₁₁ to 3.0 _§ measured at 190 and 2.161 하 load, / 10 ₁ can be ₁₁ days.

 Although the weight ratio between the polyolefin and the ethylene vinyl acetate copolymer contained in the binder resin is not particularly limited, for example, the binder resin may include a polyolefin: ethylene vinyl acetate copolymer in a weight ratio of 1: 1 to 6: 1 have. As described above, the dissolution rate of the fertilizer can be more easily controlled as the binder resin contains the polyolefin resin equal to or more than the ethylene vinyl acetate copolymer. On the other hand, the photocatalytic composite may have a structure in which a (co) polymer containing at least one repeating unit selected from the group consisting of ethylene repeating units and vinyl acetate repeating units is bonded to the surface or inside of aggregates of inorganic fine particles.

 As described above, the agglomerate of the inorganic fine particles can act as a photocatalyst, and when the dissolution-controlled fertilizer is exposed to the surface of the soil or the like, the photolytic reaction can be started in the photodegradable capsule.

The (co) polymer containing at least one repeating unit selected from the group consisting of the ethylene repeating unit and the vinyl acetate repeating unit is preferably a 2019/117650 1 ^» (: 1 ^ 1 {2018/015866

The inorganic fine particles are prevented from excessively growing in size and have higher compatibility with the binder resin so that the photocatalytic composite is uniformly dispersed in the binder resin, .

_5, including the ethylene repeating units and vinyl acetate repeating units _one or more kinds selected from the group consisting of repeating units of the (co) polymer can contain both an ethylene vinyl acetate repeating units, or repeating units thereof. Examples of the above ethylene repeating units and vinyl acetate (co) including a repeating unit selected at least _one from the group consisting of repeating units of the polymer is ₁₀ and the number of the ethylene vinyl acetate copolymers, and vinyl acetate repeating units _{from 1%} to by weight ₄₅ may be used an ethylene-vinyl acetate copolymer containing by _weight%. In addition, the ethylene-vinyl acetate copolymer shows況1) on by _{1901 1238:} and _{2.16} ¾} load a melt index of _0.5 for a / ₁₀ to _5.0 for a / _{10 1 or} / _{101 11} - / ₁₀ per _{3.0 1.0} measured at ^ Can be.

 15

The photocatalyst composite may be prepared through the step of dispersing (co) polymer containing a repeating unit at least _one selected from the group consisting of the inorganic fine particles and the ethylene repeating units and vinyl acetate repeating units in the organic solvent.

_20. The photocatalytic composite of claim 1,

The weight ratio of the inorganic fine particles (co) polymer is not limited to a great extent, and the weight ratio can be controlled by controlling the amount of the organic fine particles dispersed in the organic solvent according to the characteristics of the dissolution control type fertilizer. It can be contained in ₁₀₀ parts by weight of the aggregate compared to the ethylene repeating units and ₂₅ vinyl (co) polymer, from ₁ to ₅₀₀ parts by weight of a repeating unit including at least _one selected from the group consisting of acetate repeating units, or _{from 20} to ₂₀₀ parts by weight. On the other hand, _0.1 to ₈ parts by weight of ₃₀ aggregates of the inorganic fine particles may be included relative to ₁₀₀ parts by weight of the binder resin. 2019/117650 1 ^» (: 1 ^ 1 {2018/015866

If the content of the aggregate of the inorganic fine particles relative to the binder resin in the photodegradable capsule is too low, the photolysis reaction efficiency may be lowered, and the entire photodegradable capsule may not be decomposed due to insufficient photolysis reaction, . Also, in the photodegradable capsule, if the content of the aggregate of the inorganic fine particles relative to the 5-binder resin is too large, the agglomerate of the inorganic fine particles may grow to a large extent, thereby causing a local photodegradation reaction in the photodegradable capsule, The efficiency of the photolysis reaction is lowered, so that the entire photodegradable capsule is not decomposed and the residue may remain.

₁₀ On the other hand, the release-controlled fertilizer may further comprise a filler to be dispersed in the binder resin but are not the kind of the filler largely limited, and for example the filler is talc, bentonite, yellow earth, diatomaceous earth, silica-alumina Silicate, kaolite, starch, carbon, or a mixture of _two or more thereof.

₁₅ The content of the filler is not limited, but the lumber-controlling type fertilizer may contain ₂₅ to _{75 %} by weight of the filler in relation to the total weight of the photodegradable capsule in consideration of the mechanical properties and structural stability of the photodegradable capsule

₂₀ The fertilizer may be any of a variety of known fertilizers, such as urea or compound fertilizer. In a preferred embodiment, the fertilizer may be a granular core fertilizer having a granular form in order to be easily contained in the photodegradable capsule.

 The specific kind of the above-mentioned fertilizer is not limited, and conventionally known fertilizers can be used. Preferred examples are urea, aldehyde condensation element

₂₅ isobutylaldehyde condensation element, formaldehyde condensation element guanyl ureasulfate, and nitrogen containing organic compounds such as oxamide, ammonium nitrate, ammonium dihydrogenphosphate, ammonium dihydrogenphosphate, ammonium sulfate ammonium chloride, and ammonium nitrate such as sodium nitrate And potassium salts such as potassium nitrate, potassium nitrate, potassium phosphate, potassium sulfate, and potassium chloride, calcium phosphate, calcium sulfate, calcium nitrate,

₃₀ calcium salts, magnesium nitrate, magnesium chloride, magnesium phosphate, and Iron salts such as ferric chloride, ferric nitrate, ferric phosphate, ferric phosphate, ferrous sulfate, ferric sulfate, ferrous chloride and ferric chloride, and their double salts or a mixture of two or more thereof.

 The content of the fertilizer in the leaching control type fertilizer is not limited to a great extent. For example, 100 parts by weight of the photodegradable capsule may contain 200 to 3000 parts by weight of the fertilizer. The photocatalytic composite may have a specific degree of dispersion in the photodegradable capsule. More specifically, the photocatalytic composite can be produced by dispersing (co) polymer containing the inorganic fine particles and one or more repeating units selected from the group consisting of ethylene repeating units and vinyl acetate repeating units in an organic solvent ,

 A high-shear mixer or a bead mill may be used to disperse the inorganic fine particles and the (co) polymer in an organic solvent to transfer strong energy to the (co) polymer May be bonded to the surface or inside of the aggregate of the inorganic fine particles. The photocatalytic composite thus produced can be dispersed very uniformly in the binder resin, and the decomposition efficiency of the photocatalyst can be remarkably increased.

 The lanyard-controlled fertilizer may further comprise a component included in a known line-controlled fertilizer. For example, such components include, but are not limited to, amphipathic polymers. The leaching control type fertilizer can be provided through various manufacturing methods. For example, the dispersion of inorganic fine particles is dispersed in an organic solvent to which an ethylene vinyl acetate copolymer is added to prepare a dispersion of the photocatalytic composite. Preparing a coating composition by mixing a polyolefin, an ethylene vinyl acetate copolymer, a dispersion of the photocatalytic composite, and optionally a filler; And coating the surface of the granular fertilizer core with the coating composition.

Although specific examples of the organic solvent are not limited, 2019/117650 1 ^» (: 1 ^ 1 {2018/015866

Tetrachlorethylene 0, cyclone nucleus ((:), dichloromethane 0X1), or 1,2,4 _- trichlorobenzene 01 _¾ ).

In the step of dispersing the inorganic fine particles in the organic solvent to which the ethylene vinyl acetate copolymer is added to prepare the dispersion of the photocatalytic composite, a dispersion can be prepared by using a strong energy such as a 5-ultrasonic wave ( ₁₁ ratio 1 ₀₁₁ ) or a bead mill For example, ultrasonic waves ( ₃₀₁₁ ratio ₃₁ ; 1 is ₁ ), etc.

 Can be prepared.

 【Effects of the Invention】

₁₀ According to the present invention, it is possible to provide a controlled-release fertilizer having a high stability against moisture, a solid structure, and a controllability of a dissolution period of the fertilizer and an excellent photodegradation efficiency.

 The dissolution-controlled fertilizer prevents the photodegradable capsule or the hydrophilic polymer from remaining in the soil, thereby preventing soil contamination.

₁₅ [Brief Description of Drawings]

Fig. ₁ is a table photograph of each of the agglomerates of inorganic fine particles and the agglomerates of fine particles contained in the coated fertilizer of Comparative Example ₂ in Example ₁ and the photocatalytic composite contained in the dissolution-controlled fertilizer.

Figure ₂ schematically depicts the photodegradation mechanism of a dissolution-controlled fertilizer

₂₀ .

 DETAILED DESCRIPTION OF THE INVENTION

 The invention will be described in more detail in the following examples. However, the following examples are illustrative of the present invention, and the present invention is not limited by the following examples.

 25

 [Example: Preparation of dissolution-controlled fertilizer]

 Examples 1 to 3

( ₁ ) Production of photocatalytic composite

Ethylene Vinyl Acetate Copolymer [ū 0 (Melt Index, 1901: 2.161 _¾ load, 2019/117650 1 ^» (: 1 ^ 1 {2018/015866

 Ultrasonic waves were applied to prepare 5 dispersions of the photocatalytic composite coated with ethylene vinyl acetate copolymer.

 (2) Production of dissolution-controlled fertilizer

Dispersion of the above-prepared photocatalyst composite, polyethylene比^ ¾, (melt index, 190, 2.161 _¾ load, shows況1) 1238): about 8 _{§ / 10111111, 1)} (density): 0.925 / 0 ₁₁ ^3] for, Ethylene vinyl acetate copolymer [(Melt Index, 19010,

To 0.94 Melting /刷^3, about 20% by weight vinyl acetate content, a melting point 85 ° 0], and talc: ₁₀ 2.161 _¾ load, shows況1) 1238): about 1.8 / 10 mi, 1) for the (density) Using the contents as shown in Table 1, the mixture was homogeneously mixed with tetrachlorethylene at a mixing ratio of 100: 1 in terms of composition and mixing ratio to prepare a coating solution having a solid concentration of 5% by weight.

₁₅ Then, the coating solution was applied to the nitrogen fertilizer particles using a fluidized bed dryer to prepare dissolution-controlled coated fertilizers (Examples ₁ to ₅ ).

[Comparative Examples 1 and 2: Preparation of coated fertilizer]

 Comparative Example 1

₂₀ polyethylene比^ ¾, (melt index, 1901 :, 2.161 _¾ load, shows況¾1 1) 1238): about 8/10 _{1 11,} IX for density): 0.925 I / 0 ₁₁ ^3], ethylene vinyl acetate copolymer [(Melt index, 190, 2.16, 1) 1238): about 1.8 is /!,

1) (density): 0.94 _§八:, vinyl acetate content about 20 wt%, a melting point of 85 yae], and to the talc by using a content according to Table 1 ₂₅ tetrachlorethylene and 100 ° to the mixing ratio of composition (: , And a coating solution was prepared so that the solid content concentration became 5% by weight.

Then, the coating liquid was applied to the nitrogen fertilizer particles using a fluidized bed dryer to prepare coated fertilizer (Comparative Example ₁ ).

30 Comparative Example 2 (Average particle diameter of primary particles: 21 ■) of 2019/117650 1 (: 1 ^ {2018/015866 0 ₂ ), polyethylene

(Density): 0.925 dl), Ethylene Vinyl Acetate Copolymer 1 (Melt Index, Melt Index, Melt Index, 190 ^° 0, 1901], 2. 161¾ load, shows況1) 1238): about 1.8 I / 10 _{1 11,} I) (density): 0.94 _§ / ₀₁₁ ³⁾ about 20% by weight vinyl acetate content, a melting point 85 ^° 0], And talc were mixed with tetrachlorethylene at a mixing ratio of 100: 1 at a mixing ratio of 100: 1 by using the ingredients as shown in Table 1, and a coating liquid was prepared so that the solid concentration was 5% by weight.

 Then, the coating liquid was applied to the nitrogen fertilizer particles using a fluidized bed dryer to prepare coated fertilizer (Comparative Example 1).

[Experimental Example]

 Experimental Example 1: Comparison test of photodegradation characteristics

 After taking out the pinholes with one needle each, the internal fertilizer was completely eluted and the degradation evaluation was carried out with the remaining coating film.

Equipment at temperatures of 50 ° C to 300 ° C

The coating film was irradiated with light having a wavelength of 800 ₁ L at an intensity of 40 (½ / ₁₁₁ ² ).

 The degradation rate of the binder resin, which is also reduced by the weight change of the coating film upon irradiation with light for 224 hours under the above conditions, was determined by the following general formula 1, and the results are shown in Table 1 below.

 [Formula 1]

 Cool down the binder resin

X: 100 candles

[Table 1]

2019/117650 1 ^» (: 1 ^ 1 {2018/015866

Wherein, as shown in Table _{1, the} embodiment of dissolution-controlled fertilizer to about _300, to the light having a wavelength of _{800 ™} to a ₄₀₀ / strength than the _40% decomposition of the binder resin when irradiated with light for ₂₂₄ hours, and _55% , Whereas the coated fertilizer of the comparative example showed a decomposition rate of the binder resin of _35% or less. EXPERIMENTAL EXAMPLE ₂ Evaluation of Dissolution Characteristics of Fertilizer

The release-controlled fertilizer of the above-mentioned example and the coated fertilizer of the comparative example

[Table 2]

As shown in Table ₂ , it was confirmed that the dissolution-controlled type fertilizer of the Example exhibited a dissolution rate of _50% or more after ₂₀ days and showed a dissolution rate of _90% or more after ₅₀ days, whereas the coated fertilizer of Comparative Example showed that after ₂₀ days _It showed a dissolution rate of _40% or less and showed a dissolution rate of _70% or less even at ₅₀ days. Experimental Example 3: Measurement of z-average dispersion particle size of Ti

The z-average dispersion particle size of the TiO ₂ of the dispersion containing the photocatalytic composite of Example ₁ and the Ti¾ of Comparative Example ₂ was measured using _{Dynamic Light} Scatterin _g (M _arvern Ze _tasizer Nano ZS ₉₀ ). The results are shown in Table ₃ below.

[Table 3] 0 ₂ _ Average dispersed particle size

As shown in Table ₂ , the photocatalytic composite of Example ₁

It is dispersed homogeneously, and that the check point is relatively formed with a agglomerates of the inorganic fine particles having a small average particle diameter, which況_¾1 control _3: the embodiment in Figure ₁ observed in the photocatalytic composite ₁ using _(3-4800)況is confirmed by _¾伴photos.

On the other hand, Comparative Example ₂ 0 ₂ 0 ₂ of the saturable also the dispersion is at least about _{10,000 ^ 2 -} is confirmed that that form aggregates of the inorganic fine particles having an average particle diameter of relatively large gajyeoseo the average dispersed particle size, which is the comparative example ₂ of

 Is confirmed.

Claims

2019/117650 1 ^» (: 1 ^ 1 {2018/015866

Claims:

 [Claim 1]

A polyolefin, and (co) polymers, including ethylene vinyl acetate binder resin, and ethylene repeating units and vinyl acetate repeating unit repeating unit at least _one selected from the 5 group consisting of containing a copolymer bonded to the surface or inside of the agglomerates of the inorganic fine particles Photodegradable capsules comprising a photocatalytic composite and

 And a fertilizer contained in a space surrounded by the photodegradable capsule.

₁₀

 [Claim 2]

 The method according to claim 1,

Wherein the decomposition rate of the binder ₁₅ resin derived from the weight change of the photodegradable capsule is _40% or more upon irradiation with light having a wavelength of 300 to 800 占 at an intensity of 400/224 hours.

[Claim ₃ ]

 The method according to claim 1,

_Wherein said inorganic microparticles comprise primary ₂₀ particles having a cross-sectional diameter of from 5 to 50 &lt; RTI ID = 0.0 &gt; _11111. &lt; / RTI &gt;

[4]

 The method according to claim 1,

The aggregate of the inorganic fine particles having the cross-sectional diameter of less than _1, the elution _{of 25-regulating} fertilizer.

[Claim ₅ ]

 The method according to claim 1,

Wherein the agglomerates of the inorganic fine particles have a cross section ₃₀ diameter of from _0.05 m to _0.5 mu m. 2019/117650 1 »(: 1 ^ 1 {2018/015866

[Claim 6]

 The method according to claim 1,

Wherein the inorganic fine particles are titanium dioxide: (0 ₂ ), zinc oxide (), or a mixture thereof.

[7]

 The method according to claim 1,

 Wherein the photocatalytic composite comprises 1 to 500 parts by weight of a (co) polymer containing at least one repeating unit selected from the group consisting of ethylene repeating units and vinyl acetate repeating units, with respect to 100 parts by weight of aggregates of the inorganic fine particles. .

8.

 The method according to claim 1,

 And 0.1 to 8 parts by weight of aggregates of inorganic fine particles relative to 100 parts by weight of the binder resin.

9]

 The method according to claim 1,

 Wherein the weight ratio of the polyolefin: ethylene vinyl acetate copolymer in the binder resin is 1: 1 to 6: 1.

Claim 10

 The method according to claim 1,

Wherein the polyolefin is at least one selected from the group consisting of high density or low density polyethylene, linear low density polyethylene, polypropylene, ethylene-propylene copolymer, polybutene, butene-ethylene copolymer and butene-propylene copolymer. 2019/117650 1 ^» (: 1 ^ 1 {2018/015866

Claim ₁₁

 In the provision of

Wherein said ethylene vinyl acetate copolymer comprises from 1 _% to _{45 %} by weight of vinyl acetate repeat units.

₅

Claim ₁₂

 The method according to claim 1,

Wherein the (co) polymer comprising at least one repeating unit selected from the group consisting of ethylene repeat units and vinyl acetate repeat units comprises ₁₀ ethylene vinyl acetate copolymers.

Claim ₁₃

 The method according to claim 1,

And a filler dispersed in the binder resin. ₁₅

 (Ii)

 14. The method of claim 13,

Wherein the filler is at least ₂₀ selected from the group consisting of talc, bentonite, loess, diatomaceous earth, silica, aluminosilicate, kaolite, starch and carbon.

_15.

14. The method of claim ₁₃ ,

Photodegradable additive, based on the weight of the entire capsule, dissolution-controlled fertilizer to ₂₅ containing the filler ₂₅ to _75% by weight.

Claim ₁₆

 2. The leaching control type fertilizer according to claim 1, wherein the fertilizer is a granular fertilizer.

₃₀ [Claim ₁₇ ] 0 2019/117650 1> (/ 1 technique 018/015866

The method according to claim 1,

 And 200 to 3000 parts by weight of the above-mentioned fertilizer with respect to 100 parts by weight of the photodegradable capsule.