JPS6037074B2 - Coated fertilizer and its manufacturing method - Google Patents

Coated fertilizer and its manufacturing method

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Publication number
JPS6037074B2
JPS6037074B2 JP53160192A JP16019278A JPS6037074B2 JP S6037074 B2 JPS6037074 B2 JP S6037074B2 JP 53160192 A JP53160192 A JP 53160192A JP 16019278 A JP16019278 A JP 16019278A JP S6037074 B2 JPS6037074 B2 JP S6037074B2
Authority
JP
Japan
Prior art keywords
vinyl acetate
weight
resin
fertilizer
ethylene
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
JP53160192A
Other languages
Japanese (ja)
Other versions
JPS5590495A (en
Inventor
利雄 藤田
知剛 高橋
重光 吉田
秀秋 中谷
光男 徳永
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Chisso Asahi Fertilizer Co Ltd
Original Assignee
Chisso Asahi Fertilizer Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Chisso Asahi Fertilizer Co Ltd filed Critical Chisso Asahi Fertilizer Co Ltd
Priority to JP53160192A priority Critical patent/JPS6037074B2/en
Publication of JPS5590495A publication Critical patent/JPS5590495A/en
Publication of JPS6037074B2 publication Critical patent/JPS6037074B2/en
Expired legal-status Critical Current

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Description

【発明の詳細な説明】 従来から植物の要求に合うように人為的に肥料成分の供
給を調節するため、あるいは肥料粒子の吸温や固結を防
止するため肥料成分を高分子重合体で被覆した被覆粒状
肥料に関する研究開発がなされてきた。
[Detailed Description of the Invention] Conventionally, fertilizer components have been coated with high molecular weight polymers in order to artificially adjust the supply of fertilizer components to meet the needs of plants, or to prevent fertilizer particles from absorbing heat or solidifying. Research and development has been conducted on coated granular fertilizers.

高分子重合体は熱硬化性のものと熱可塑性のものに大別
されるが、上記目的には何れの重合体も使用される。例
えば英国特許954555にはスチレン化アルキッド樹
脂とフェノール樹脂、特公昭40−28927には脂肪
油変性アルキッド樹脂、脂肪油ジシクロベンタジェン共
重合体、ジイソシァネート変性脂肪油重合体、特公昭4
4−28457にはフェノール樹脂等の熱硬化性樹脂が
使用できることが示されている。また英国特許8158
29には被覆材としてスチレン、塩化ビニル、塩化ビニ
リデン、アクリルニトリルェチレン及びフッ化ァルカン
の重合体あるいは共重合体等の熱可ソ性樹脂を用いるこ
とが示されている。更に特公昭37−15832では被
覆材として酢酸ビニール乳化重合液を用いることが示さ
れている。高分子重合体特に熱可ソ性樹脂溶液或はその
乳化重合液等を被覆材として用いた時の問題点として特
公昭42一13681には粒状物質表面に液状樹脂また
は曳糸性樹脂を被覆させると樹脂の曳糸性のためわずか
数%の樹脂が被覆される丈で粒子は粘着し合ってブロッ
クを作ってしまい個々の粒状物とはならず均一に厚く被
覆することは不可能であり肥料成分の熔出速度を遅くす
ることは困難であることが示されている。
High molecular weight polymers are broadly classified into thermosetting ones and thermoplastic ones, and either type of polymer can be used for the above purpose. For example, British Patent No. 954555 describes styrenated alkyd resins and phenolic resins, Japanese Patent Publication No. 40-28927 discloses fatty oil-modified alkyd resins, fatty oil dicyclobentadiene copolymers, diisocyanate-modified fatty oil polymers,
No. 4-28457 indicates that thermosetting resins such as phenolic resins can be used. Also British patent 8158
No. 29 discloses the use of thermoplastic resins such as polymers or copolymers of styrene, vinyl chloride, vinylidene chloride, acrylonitrileethylene, and fluorinated alkanes as coating materials. Furthermore, Japanese Patent Publication No. 37-15832 discloses the use of a vinyl acetate emulsion polymerization solution as a coating material. As a problem when using high-molecular polymers, especially thermoplastic resin solutions or their emulsions as coating materials, Japanese Patent Publication No. 42-13681 describes coating the surface of granular materials with liquid resin or stringable resin. Due to the stringiness of the resin, the particles adhere to each other and form blocks when only a few percent of the resin is coated, making it impossible to coat them uniformly and thickly, making it difficult to coat the fertilizer with a uniform thickness. It has been shown that it is difficult to slow down the elution rate of the components.

特開昭50−99858、特開昭51−75674、特
関昭53−98265は本願発明者らによって発明され
た粒状肥料の被覆方法に関する出願に係るものであるが
、これらの公報には樹脂溶液の性質と乾燥条件の選択に
よって被覆工程でブロッキングを起すことなく一工程で
能率よく被覆できる方法が示されている。
JP-A-50-99858, JP-A-51-75674, and JP-A-53-98265 are related to applications for coating methods for granular fertilizers invented by the inventors of the present application. A method has been shown in which coating can be efficiently performed in one step without causing blocking during the coating process by selecting the properties of and drying conditions.

侍開昭50−99858はポリオレフインを主成分とす
る被覆材料で粒状肥料を被覆する際に粒状肥料に被覆材
料の溶液を靖露し、被覆すると同時に好ましくは15m
/秒以上の熱風で乾燥し粒状肥料を被覆する方法が示さ
れている。この技術の特徴は■極めて薄い被膜で完全に
被覆することができる点と■被膜内に界面活性剤等の溶
出調整剤を適宜分散し溶出速度を調節することができる
点にある。また特関昭51−75674はポリ塩化ビニ
リデン系の樹脂と酢酸ビニール部分が5重量%以下のエ
チレン一驚酸ビニール共重合体がポリオレフィン樹脂と
同様に極めて薄い被膜で粒状肥料を完全に被覆できるこ
とを開示している。ポリオレフィンを主成分とする被膜
内に界面活性剤を均一に分散して溶解速度を調節する上
記の公知技術によって作られた被覆粒状肥料では界面活
性剤の効果が不安定であり、基材となるポリオレフィン
は比較的柔軟性が乏しく肥料粒子との接着性が弱いため
製品を急冷したり、温度変化の激しい屋外等に保管した
場合に凹部に付着している被膜が剥離し、輸送中に機械
的衝撃が与えられると被膜が被れ、被覆の効果が一部損
なわれる場合がある。
Samurai Kaisho 50-99858 discloses that when coating granular fertilizer with a coating material mainly composed of polyolefin, a solution of the coating material is applied to the granular fertilizer, and at the same time as coating, preferably 15 m.
A method of coating the granular fertilizer by drying it with hot air at a speed of 1/sec or more is shown. The features of this technology are: (1) it is possible to completely cover the product with an extremely thin film, and (2) the elution rate can be adjusted by appropriately dispersing an elution regulator such as a surfactant within the film. In addition, Tokusei Sho 51-75674 reported that polyvinylidene chloride resin and ethylene monomonovinyl acid copolymer containing less than 5% by weight of vinyl acetate can completely cover granular fertilizer with an extremely thin film, similar to polyolefin resin. Disclosed. The effect of the surfactant is unstable in coated granular fertilizers made by the above-mentioned known technology, in which the dissolution rate is adjusted by uniformly dispersing the surfactant in a film containing polyolefin as the main component, and the surfactant becomes a base material. Polyolefin is relatively inflexible and has weak adhesion to fertilizer particles, so if the product is rapidly cooled or stored outdoors with rapid temperature changes, the film adhering to the recesses may peel off, causing mechanical damage during transportation. If an impact is applied, the coating may wear off and some of the effectiveness of the coating may be lost.

また溶出速度をより速めるために界面活性剤を多量用い
た場合とか少くとも2年以上の長期保存試験結果によれ
ば長期保管する場合に機械的衝撃がなくても被覆にクラ
ックが生成する等の欠点が認められた。この原因は明確
ではないが、■被覆工程では粒子は50〜9000に保
持されつ)被覆されるが通常の取扱は常温であるため、
被膜が若干収縮して引張られた状態にあること。■界面
活性剤による港出促進の主原因は微細な亀裂生成による
もので、ポリオレフィン樹脂の性質のわずかな違いによ
って溶出速度が影響を受ける等の理由が考えられる。ま
たポリ塩化ビーニリデン系樹脂を用いる肥料粒子を被覆
する場合、わずかな温度変化で樹脂溶液がゲル化するの
で他の樹脂、例えばポリスチレン等と併用する場合それ
らの樹脂と熔解特性が違うので使用しにくい欠点がある
。本発明者らは上言己の欠点をなくし、被覆粒状肥料の
熔出特性の保管・輸送性をさらに安定化するために鋭意
研究を重ねた結果、公知方法に用いられている高分子樹
脂の中より特定の樹脂組成物を選択し、これに必須の第
3成分を混合することによって上記した初期の目的を達
成することができ本発明を完成するに至った。
In addition, when a large amount of surfactant is used to increase the elution rate, the results of long-term storage tests of at least two years have shown that cracks may form in the coating even without mechanical impact during long-term storage. Defects were recognized. The reason for this is not clear, but (1) During the coating process, the particles are maintained at a particle size of 50 to 9,000 and are usually handled at room temperature.
The film should be slightly contracted and stretched. ■The main reason for the promotion of ejection by surfactants is the formation of fine cracks, and one possible reason is that the elution rate is affected by slight differences in the properties of the polyolefin resin. In addition, when coating fertilizer particles using polyvinylidene chloride resin, the resin solution turns into a gel with a slight temperature change, making it difficult to use in combination with other resins, such as polystyrene, as the melting characteristics are different from those resins. There are drawbacks. The inventors of the present invention have conducted intensive research to eliminate the above-mentioned drawbacks and further stabilize the storage and transportation properties of coated granular fertilizers. By selecting a specific resin composition from among them and mixing it with an essential third component, the above-mentioned initial objective could be achieved and the present invention was completed.

即ちポリオレフィン系樹脂を第1樹脂成分とし、これに
酢酸ビニールが20−4の重量%含まれるエチレン−酢
酸ビニール共重合体を第二樹脂成分として分散させた樹
脂組成物に更に界面活性剤を必須の第3成分として分散
させた被膜で被覆するとこれらの樹脂成分並びに界面活
性剤成分の混合割合によって、保存安定性が優れた種々
の溶出速度のものが得られることがわかり本発明が完成
された。本発明はポリオレフィン系樹脂に酢酸ビニール
を20−4の重量%含むエチレン−酢酸ビニール共重合
体を樹脂組成物に対して10一5の重量%の範囲で均一
に混合した樹脂組成物を主成分としこれに必須の第3成
分としてHLB価が6−20、好ましくは9−16の界
面活性剤を上記樹脂組成物の0.01〜1の重量%の範
囲に分散した被膜で被覆した粒状肥料とその製造方法に
関するものである。
That is, a surfactant is essential to a resin composition in which a polyolefin resin is used as a first resin component and an ethylene-vinyl acetate copolymer containing 20-4% by weight of vinyl acetate is dispersed as a second resin component. It was found that by coating with a film dispersed as the third component of the resin component, it was possible to obtain various dissolution rates with excellent storage stability depending on the mixing ratio of these resin components and surfactant components, and the present invention was completed. . The main component of the present invention is a resin composition in which an ethylene-vinyl acetate copolymer containing 20-4% by weight of vinyl acetate is uniformly mixed with a polyolefin resin in a range of 10-5% by weight based on the resin composition. A granular fertilizer coated with a film in which a surfactant having an HLB value of 6-20, preferably 9-16 is dispersed as an essential third component in a range of 0.01 to 1% by weight of the resin composition. and its manufacturing method.

本発明のポリオレフィン系樹脂はオレフィン重合体の総
称であって重合法や重合度に制約されることなく、エチ
レン重合体、ブロピレン重合体、エチレンープロピレン
共重合体等が好ましい樹脂としてあげられるが、最も好
ましいものは低密度ポリエチレンである。
The polyolefin resin of the present invention is a general term for olefin polymers, and preferred resins include ethylene polymer, propylene polymer, ethylene-propylene copolymer, etc. without being restricted by the polymerization method or degree of polymerization. Most preferred is low density polyethylene.

本発明に使用されるエチレン−酢酸ビニール共重合体は
エチレンと酢酸ビニールの共重合体であり重合法、重合
度に特に制約はなく、市販のものを適宜使用することが
できるが、好ましいものは高圧重合法によって得られた
ものである。
The ethylene-vinyl acetate copolymer used in the present invention is a copolymer of ethylene and vinyl acetate, and there are no particular restrictions on the polymerization method or degree of polymerization, and commercially available products can be used as appropriate, but preferred ones are It was obtained by high pressure polymerization method.

本発明の効果である被膜を通しての肥料の溶出速度調節
の機構は不明であるが、ポリオレフィン系樹脂とエチレ
ン−酢酸ビニール共重合体は化学構造上比較的類似のも
のであり、溶剤に対する親手01性も類似点が多い。例
えば酢酸ビニール単位含量の少し、エチレン−酢酸ビニ
ール共重合体はエチレン共重合体と同種の扱いを受ける
。従って溶剤等に両者を熔解すれば分子レベルで均一に
分散した混合溶液が作られる。しかし特開昭50−99
858等の方法によって粒状肥料等に塗布すると、酢酸
ビニール分の少し、エチレン−酢酸ビニール共重合体と
ポリオレフィン樹脂からなる組合せと酢酸ビニール分の
多いものからなる組合せとでは構造上の相異が生ずる、
即ち、酢酸ビニール分の少いエチレンとの共重合体とポ
リオレフィソは樹脂同志の相溶性がよく分子状の均一混
合状態を保持しているのに反し、酢酸ビニール分の多い
共重合体とポリオレフィンからなる被膜では相溶性が若
干劣るため相互の分子は適当に反発し合って同種の樹脂
同志が集合し合い結果的に“海−島”の関係が生ずる。
本発明では海に相当する部分がポリオレフィン系樹脂で
あり、島に相当する位置にエチレン−酢酸ビニール共重
合体があると考えられるが、鯵透圧等のわずかな内部応
力によって海−島間の接触面にずれが起り、イオンが通
過できる間隙が生成する。しかし乍ら、ポリオレフィン
等の樹脂は疎水性がつよいため肥料成分の自由な通過を
防げる傾向がある。本発明に於いて用いる界面活性剤の
作用は上言己の疎水孔を肥料成分が通過するに際し、相
互の親和性を高め通過し易くする潤滑剤の作用をするも
のと想定される。本発明に用いられる界面活性剤を一日
LB価で表わせばその目安は6〜20であり、好ましい
範囲は9−16である。
Although the mechanism of controlling the elution rate of fertilizer through the film, which is an effect of the present invention, is unknown, polyolefin resins and ethylene-vinyl acetate copolymers are relatively similar in chemical structure, and their compatibility with solvents. There are also many similarities. For example, an ethylene-vinyl acetate copolymer with a low vinyl acetate unit content is treated in the same way as an ethylene copolymer. Therefore, by dissolving both in a solvent or the like, a mixed solution in which they are uniformly dispersed at the molecular level can be created. However, JP-A-50-99
When applied to granular fertilizer etc. using a method such as 858, structural differences occur between a combination consisting of a small vinyl acetate content, ethylene-vinyl acetate copolymer and polyolefin resin, and a combination consisting of a large vinyl acetate content. ,
In other words, copolymers with ethylene that have a low vinyl acetate content and polyolefin have good compatibility between resins and maintain a homogeneous molecular mixture, whereas copolymers with a high vinyl acetate content and polyolefin Since the compatibility of these films is slightly inferior, the molecules repel each other appropriately, and resins of the same type gather together, resulting in a "sea-island" relationship.
In the present invention, the part corresponding to the sea is made of polyolefin resin, and it is thought that the ethylene-vinyl acetate copolymer is located in the position corresponding to the island. A shift occurs in the plane, creating a gap through which ions can pass. However, resins such as polyolefins tend to prevent the free passage of fertilizer components due to their strong hydrophobicity. The surfactant used in the present invention is assumed to act as a lubricant to enhance mutual affinity and facilitate passage of fertilizer components when they pass through the hydrophobic pores of the fertilizer component. The daily LB value of the surfactant used in the present invention is approximately 6 to 20, and the preferred range is 9 to 16.

一般にHLB価が高すぎると樹脂との親和性が劣り、界
面活性剤を被膜内に均一に分散させることができないの
で効果が期待できない。またHLB価が低すぎる場合に
は肥料水溶液との親和性がなくなり被膜内に均一に分散
させても潤滑剤としての作用がない。これらの界面活性
剤は単独であっても混合物であっても用いることができ
るが、その使用量は樹脂組成物重量に対して0.01〜
1の重量%の範囲が実用的であり、その範囲以下では潤
滑作用が期待できない。またそれ以上添加しても効果が
平衡に達して追加効果は明確でない。本発明に用いられ
界面活性剤としては (1} 非イオン性界面活性剤に属するものにM ポリ
オキシェチレンアルキルェーテル類、例えばポリオキシ
ェチレンラウリルェーテル(このポリオキシエチレンラ
ウリルエーテルのオキシェチレンのモル数が4〜15の
ものが好ましい)。
Generally, if the HLB value is too high, the affinity with the resin will be poor, and the surfactant cannot be uniformly dispersed in the coating, so no effect can be expected. Furthermore, if the HLB value is too low, it will have no affinity with the fertilizer aqueous solution and will not function as a lubricant even if it is uniformly dispersed within the coating. These surfactants can be used alone or in a mixture, but the amount used is 0.01 to 100% based on the weight of the resin composition.
A range of 1% by weight is practical, and below that range no lubricating effect can be expected. Moreover, even if more than that is added, the effect reaches an equilibrium and the additional effect is not clear. Surfactants used in the present invention include (1) Those belonging to nonionic surfactants include M polyoxyethylene alkyl ethers, such as polyoxyethylene lauryl ether (this polyoxyethylene lauryl ether); The number of moles of oxyethylene is preferably 4 to 15).

(ロ)ポリオキシエチレンアルキルフエニルエーテル類
、例えばポリオキシェチレンオクチルフェニルェーテル
(このモル数が4〜20のものが好ましい)。
(b) Polyoxyethylene alkyl phenyl ethers, such as polyoxyethylene octylphenyl ether (preferably, the number of moles thereof is 4 to 20).

し一 ポリエチレングラィコールと脂肪酸とのェステル
類、例えばラウリル酸モノェステル(このラウリン酸モ
ノェステルのポリエチレングライコールの分子量が20
0〜1000のものが好ましい)。
Esters of polyethylene glycol and fatty acids, such as lauric acid monoester (the polyethylene glycol of this lauric acid monoester has a molecular weight of 20
0 to 1000 is preferred).

8 ポリオキシェチレンソルビタン脂肪酸モノェステル
類、例えばポリオキシェチレンソルビタンステアリン酸
ェステル(このポリオキシェチレンソルビタンステアリ
ン酸ェステルのオキシェチレンのモル数が2〜30のも
のが好ましい)。■ ポリオキシェチレンアミン類また
はアマィド等がある。
8. Polyoxyethylene sorbitan fatty acid monoesters, such as polyoxyethylene sorbitan stearate (the polyoxyethylene sorbitan stearate preferably has 2 to 30 moles of oxyethylene). ■ Contains polyoxyethylene amines or amides.

{2)イオン性界面活性剤に属するものに【ィ} 脂肪
酸塩類、例えばオレィン酸トリェタノールアミン。
{2) Ionic surfactants include fatty acid salts, such as triethanolamine oleate.

【o} 高級アルコールサルフェート類、例えばパルミ
チルサルフェートナトリウム塩。
[o} Higher alcohol sulfates, such as palmityl sulfate sodium salt.

し一 ジアルキルスルフオサクシネート類、例えばジエ
チルヘキシルスルフオサクシネートナトリウム塩。
1. Dialkyl sulfosuccinates, such as diethylhexyl sulfosuccinate sodium salt.

〇 アルキルベンゼンスルフオン酸塩類、アルキルナフ
タリンスルフオン酸塩類、アルキル燐酸塩類、アルキル
アミン、アルキルオキシメチルピリジニウムクロラィド
等がある。
〇 Alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl phosphates, alkyl amines, alkyloxymethylpyridinium chloride, etc.

これらのうちポリオキシエチレンアルキルェーテル類、
ポリオキシェチレンアルキルフェニルェーテル類、ポリ
エチレングライコールと脂肪酸のェステル類級びポリオ
キシェチレンソルビタン脂肪酸モノェステル類が本発明
のために好ましい。本発明の溶出特性の具体例を示すと
次の通りである。
Among these, polyoxyethylene alkyl ethers,
Polyoxyethylene alkyl phenyl ethers, ester classes of polyethylene glycol and fatty acids, and polyoxyethylene sorbitan fatty acid monoesters are preferred for the present invention. Specific examples of the elution characteristics of the present invention are as follows.

ポIJオレフィン樹脂として低密度ポリエチレンを用い
た場合、例えば酢酸ビニールを3の重量%含むエチレン
−酢酸ビニール共重合体をポリエチレンと等量混合し、
これに界面活性剤を樹脂全量の0.01重量%加えた被
覆材で直径3側程度の粒状尿素を平均厚み25叫こ被覆
した場合の25qo水中熔出率が80%に至る日数はお
よそ100日間である。また酢酸ビニール4の重量%含
むものを同様に用いた場合の溶出速度は約2割程度遠く
なり、酢酸ビニール2の重量%含むものを同様に用いた
場合は3割程度遅くなる。本発明に於いて用いる界面活
性剤は溶出速度調節作用を有するがその効果の大略の目
安は樹脂組成物に対して1%添加すると溶出速度は約5
〜10%遠くなる。
When low-density polyethylene is used as the PoIJ olefin resin, for example, an ethylene-vinyl acetate copolymer containing 3% by weight of vinyl acetate is mixed with polyethylene in an equal amount,
When granular urea with a diameter of about 3 sides is coated with a coating material containing 0.01% by weight of the total amount of resin, the average thickness of the urea is 25 cm, the time it takes for the dissolution rate in 25 qo water to reach 80% is approximately 100 days. It is days. Further, when a solution containing 4% by weight of vinyl acetate is similarly used, the elution rate is about 20% slower, and when a solution containing 2% by weight of vinyl acetate is similarly used, the elution rate is about 30% slower. The surfactant used in the present invention has an effect of regulating the elution rate, but a rough guide to its effect is that when it is added at 1% to the resin composition, the elution rate is approximately 5%.
~10% farther away.

この界面活性剤の溶出速度に及ぼす効果はポリオレフィ
ン樹脂単独に界面活性剤を添加した場合よりも小さいが
多量使用しても保存中にクラツクが生ずる欠点はない。
この理由はポリオレフィン系樹脂単独の場合の界面活性
剤の熔出促進効果は微細なクラック生成に起因するが、
本発明の場合は前述の如く、微細な疎水孔を水溶液が通
過するに際し、潤滑剤の役割をするだけでクラック生成
がないためであると考えられる。本発明の被膜はポリオ
レフィン樹脂単独の場合とは異り、比較的柔軟性があり
、急激な温度変化や屋外保管等によって粒状肥料凹部の
剥離はなく、機械的衝撃につよく、長期保存性も良好で
ある。本発明の応用としてポリオレフィン類とエチレン
−酢酸ビニール共重合体の外にワックス類や本発明の粒
状肥料を製造する際に用いる溶剤に可溶な他の高分子重
合体やタルク、炭酸カルシウム、ケイ酸塩等の無機のフ
ィラーを本発明の目的が損なわれない範囲で用いること
ができる。本発明粒状肥料の製造方法は特開昭50−9
9858に準じた方法で行うことができる。
Although the effect of this surfactant on the elution rate is smaller than when the surfactant is added to the polyolefin resin alone, there is no problem of cracks occurring during storage even if a large amount is used.
The reason for this is that when polyolefin resin is used alone, the dissolution promoting effect of the surfactant is due to the formation of fine cracks.
In the case of the present invention, as described above, this is thought to be because when the aqueous solution passes through the fine hydrophobic pores, it only acts as a lubricant and no cracks are generated. Unlike the case of polyolefin resin alone, the coating of the present invention is relatively flexible, does not peel off in the recessed parts of granular fertilizer due to sudden temperature changes or outdoor storage, is strong against mechanical shock, and has good long-term storage stability. It is. In addition to polyolefins and ethylene-vinyl acetate copolymers, the present invention may be applied to waxes, other polymers soluble in the solvent used in producing the granular fertilizer of the present invention, talc, calcium carbonate, silica, etc. Inorganic fillers such as acid salts can be used as long as the purpose of the present invention is not impaired. The method for producing the granular fertilizer of the present invention is disclosed in Japanese Patent Application Laid-Open No. 50-9
This can be done by a method similar to 9858.

即ち、使用する被覆材を炭化水素類または塩素化炭化水
素類の熱溶剤に溶解した溶液を粒状肥料に噴霧すると同
時に溶液がゼリー状にゲル化する時間的余裕を与えず瞬
間乾燥することにより得られる。瞬時乾燥の条件は粒子
温度30oo以上好ましくは50qo以上の乾燥熱風流
中で、好ましくは風速15m/秒以上で、樹脂溶液を肥
料粒子上に噴霧添加することである。また被覆用樹脂溶
液の粘度は4比p以下好ましくは2比p以下がよい。も
しタルク等のフイラ−を入れる場合は高分子重合体の連
続相を損なわない様に均一に添加する必要がある。これ
らのフィラーを被覆液に入れて用いる場合は均一性を損
なわない様に損拝する必要がある。また特関昭53−9
8265に示された様に特殊な装置を用いて乾燥用熱風
にフィラーを均一に分散することによっても可能である
。実施例 1 本実施例では各種の被覆粒状肥料の綾出特性および保存
性を比較するためのサンプルの製造法を示す。
In other words, the solution obtained by dissolving the coating material in a hot solvent of hydrocarbons or chlorinated hydrocarbons is sprayed onto granular fertilizers, and at the same time instant drying is performed without allowing time for the solution to gel. It will be done. The conditions for instant drying are that the resin solution is sprayed onto the fertilizer particles in a stream of dry hot air at a particle temperature of 30 oo or more, preferably 50 qo or more, preferably at a wind speed of 15 m/sec or more. The viscosity of the coating resin solution is preferably 4 ratio p or less, preferably 2 ratio p or less. If a filler such as talc is added, it must be added uniformly so as not to damage the continuous phase of the high molecular weight polymer. When these fillers are used in a coating solution, it is necessary to take care not to impair uniformity. Also, Tokuseki Showa 53-9
It is also possible to uniformly disperse the filler in hot air for drying using a special device as shown in No. 8265. Example 1 This example shows a method for producing samples for comparing the rolling characteristics and storage stability of various coated granular fertilizers.

本発明を実施するための装置としては瞬間乾燥の条件を
得るために噴流被覆装置を用いた。第1図は本実施例に
於いて用いた噴流被覆装置を示す。1は噴流塔で塔径2
5仇松、高さ200仇岬、空気噴出口径は5仇舷、で肥
料投入口2、排ガス噴出口3を有する。
As an apparatus for carrying out the present invention, a jet coating apparatus was used in order to obtain instant drying conditions. FIG. 1 shows the jet coating apparatus used in this example. 1 is a jet tower with a tower diameter of 2
It is 5 meters tall, 200 meters high, has an air outlet diameter of 5 meters, and has 2 fertilizer inlets and 3 exhaust gas outlets.

噴流用空気はプロアー10から送られ、オリフィス流量
計9、熱交換器8を経て噴流塔に至るが、流量は流量計
、温度は熱交換器で管理され、排ガスは排出口から搭外
に導かれる。被覆処理に供する粒状肥料は肥料投入口か
ら所定の熱風を通し乍ら投入し、噴流を形成させる。熱
風温度はT,、被覆覆粒子温度はT2、排ガス温度はT
3で検出される。被覆処理はT2が所定の温度になって
から被覆液を流体ノズル4を通して噂霧状で噴流に向っ
て吹き付ける。被覆液調製は液タンク11に所定量の被
覆材と溶材を入れ、溶剤の沸点近くで蝿拝しながら行い
、被覆操作中温度、凝梓を保持する。被覆液はポンプ5
によってノズルに供給されるが、この系は温度を保持す
るための充分な保温をしておく。所定の被覆液を供給し
たらポンプを止めた後ブロアーをとめる。被覆された肥
料は抜出口7から取り出される。なお本実施例では何れ
も下記の基本条件を保持して粒状肥料の被覆を行った。
流体ノズル:−流体用、フルコーン型関口0.8肌熱風
量:4あ′min熱風温度:10000 肥料の種類:5−7meshの粒状尿素 肥料投入量:10k9 被覆液濃度:固形分5重量% 〃 供給量:0.5k9/min 被覆時間:2の分 被覆率(対肥料):5.の重量%(但し界面活性剤分は
上乗せ)溶剤:テトラクロルェチレン 施例 2 本実施例では肥料の被覆材にポリエチレンとェチレン酢
酸ビニール共重合体の混合物を用い、その混合率を種々
変化して渚出遊度が調節できることを示す。
The jet air is sent from the blower 10, passes through the orifice flow meter 9 and the heat exchanger 8, and reaches the jet tower.The flow rate is controlled by the flow meter, the temperature is controlled by the heat exchanger, and the exhaust gas is guided outside the tower from the exhaust port. It will be destroyed. The granular fertilizer to be subjected to the coating treatment is introduced from the fertilizer input port while passing a predetermined amount of hot air to form a jet stream. The hot air temperature is T, the coating particle temperature is T2, and the exhaust gas temperature is T.
Detected at 3. In the coating process, after T2 reaches a predetermined temperature, the coating liquid is sprayed in the form of mist through the fluid nozzle 4 toward the jet stream. The coating liquid is prepared by putting a predetermined amount of the coating material and solvent into the liquid tank 11, and stirring the mixture near the boiling point of the solvent to maintain the temperature and coagulation during the coating operation. Coating liquid is pump 5
The system is supplied to the nozzle by a system that is sufficiently insulated to maintain its temperature. After supplying the specified coating liquid, stop the pump and then turn off the blower. The coated fertilizer is taken out from the outlet 7. In this example, coating with granular fertilizer was carried out while maintaining the following basic conditions.
Fluid nozzle: - For fluid, full cone type Sekiguchi 0.8 Skin hot air volume: 4 min Hot air temperature: 10000 Fertilizer type: 5-7 mesh granular urea fertilizer Input amount: 10k9 Coating liquid concentration: Solid content 5% by weight Supply rate: 0.5k9/min Covering time: 2 minutes Coverage rate (relative to fertilizer): 5. (however, the surfactant content is added) Solvent: Tetrachloroethylene Example 2 In this example, a mixture of polyethylene and ethylene vinyl acetate copolymer was used as the fertilizer coating material, and the mixing ratio was varied. This shows that the degree of beach exit can be adjusted.

第1表は実施例1に示す方法によって調製したポリエチ
レンと酢酸ビニール3の重量%含むエチレン酢酸ビニー
ル共重合体の種々の混合割合からなる樹脂組成に対し0
.01重量%の非イオン系界面活性剤(ヘキサオキシェ
チレン−nーノニルフェニルェーテル)を分散した被膜
で被覆した尿素の被膜組成と尿素80%溶出するに要し
た日数を示したものである。
Table 1 shows the results for resin compositions consisting of various mixing ratios of polyethylene and ethylene vinyl acetate copolymers containing 3% by weight of vinyl acetate prepared by the method shown in Example 1.
.. This shows the film composition of urea coated with a film in which 0.1% by weight of nonionic surfactant (hexaoxyethylene-nnonylphenyl ether) is dispersed and the number of days required for urea to elute 80%. be.

1表 なお尿素80%熔出するに要する日数は次の様にして求
めた。
Table 1 The number of days required to dissolve 80% of urea was determined as follows.

被覆品10夕を200の‘の水中に浸潰し25ooの恒
温室に静暦し10日毎に全量の水を更新する。取替えた
水中に含まれる尿素を分析し10日間の熔出率を求める
。このデータを使い、機軸に日数、縦軸に累計熔出率を
取り、曲線(溶出速度曲線)を作成し累計港出率が80
%に相当する日数を求めた。この実施例からエチレン−
酢酸ビニール共重合体を混合して広範囲に溶出日数の異
るものが得られることがわかる。
The coated product was soaked in 200 ml of water for 10 days, kept in a constant temperature room of 25 ml, and the entire amount of water was refreshed every 10 days. Analyze the urea contained in the replaced water and determine the dissolution rate for 10 days. Using this data, we created a curve (dissolution rate curve) with the number of days on the axis and the cumulative elution rate on the vertical axis, and the cumulative elution rate was 80.
The number of days corresponding to % was calculated. From this example, ethylene-
It can be seen that by mixing vinyl acetate copolymers, products with a wide range of elution days can be obtained.

更に追加説明をすると本実施例で調製したサンプルの1
0日目の水中熔出率は何れも2%以下であったが、参考
例として行ったポリエチレン40エチレン酢酸ビニール
共重合体60の混合率のものは10日目ですでに20%
も溶出した。
For additional explanation, one of the samples prepared in this example
The dissolution rate in water on the 0th day was 2% or less in all cases, but the mixture ratio of polyethylene 40 ethylene vinyl acetate copolymer 60% as a reference example was already 20% on the 10th day.
was also eluted.

このことはエチレン−酢酸ビニール共重合体が6の重量
%を越えると完全に被覆いこくいことを示している。実
施例 3 本実施例では一定比率のポリエチレンとェチレン酢酸ビ
ニール共重合体の樹脂組成に対し、実施例2と同一の界
面活性剤を0.01重量%分散して被覆するに際し、エ
チレン酢酸ビニール中の酢酸ビニール舎量をかえた場合
の尿素の綾出速度の変化を示す。
This indicates that complete coverage is not achieved when the ethylene-vinyl acetate copolymer exceeds 6% by weight. Example 3 In this example, 0.01% by weight of the same surfactant as in Example 2 was dispersed and coated in a resin composition of a fixed ratio of polyethylene and ethylene vinyl acetate copolymer. This figure shows the change in the urea deposition rate when the amount of vinyl acetate in the storage is changed.

第2表に結果を示す。第2表この結果よりエチレン酢酸
ビニールの酢酸ビニール舎量を3の重量%より4の重量
%にすると溶出所要日数は約80%に、20重量%にす
ると約130%になることがわかる。
Table 2 shows the results. Table 2 From the results, it can be seen that when the amount of vinyl acetate stored in ethylene vinyl acetate is increased from 3% by weight to 4% by weight, the number of days required for elution becomes approximately 80%, and when it is increased to 20% by weight, it becomes approximately 130%.

酢酸ビニール含量15重量%以下では溶出速度調製のた
めには効果が大きすぎるようである。(酢酸ビニール舎
量は多すぎると粘着性が増大する)実施例 4 本実施例では一定比率及び組成のポリエチレンーェチレ
ン酢酸ビニールの樹脂組成に対し、実施例2と同一の界
面活性剤を0.2〜10重量%分散した樹脂溶液で尿素
を被覆した場合の溶出速度の変化を示す。
It seems that a vinyl acetate content of 15% by weight or less is too effective for controlling the elution rate. (If the amount of vinyl acetate is too large, the adhesiveness will increase) Example 4 In this example, the same surfactant as in Example 2 was added to the resin composition of polyethylene-ethylene vinyl acetate with a fixed ratio and composition. 2 shows the change in elution rate when urea is coated with a resin solution dispersed in 2 to 10% by weight.

第3表に結果を示す。第3表 この結果より界面活性剤を樹脂に対し1重量%添加する
と、5〜10%程度の溶出期間の短縮が認められた。
Table 3 shows the results. Table 3 From the results, it was found that when 1% by weight of surfactant was added to the resin, the elution period was shortened by about 5 to 10%.

(界面活性剤は多すぎると貯蔵安定性が悪くなる。(If there is too much surfactant, storage stability will deteriorate.

)実施例 5 本実施例では保存性良否の確認例を示す。) Example 5 This example shows an example of checking whether the storage quality is good or not.

第4表は実施例1の方法によって調製した被覆粒状尿素
の製造直後と2年間500タ入の瓶に密封保存したサン
プルの25oo水中3日間の溶出率を示したものである
。第4表 水中溶出試験:サンプル10夕を200汎‘水中、5回
線返しの平均値PE:低密度ポリエチレンM120 EVA:エチレン−酢酸ビニール共重合体、(酢酸ビニ
ール33重量%)SA:界面活性剤オクタオキシェチレ
ン−n−ノニルフエニルエーテル被膜組成:樹脂組成は
PEとEVA、SAは樹脂に対する%で樹脂に上乗せし
た数字を示す。
Table 4 shows the dissolution rate of the coated granular urea prepared by the method of Example 1 immediately after production and for 3 days in 25 oo water of a sample stored sealed in a 500 ta bottle for 2 years. Table 4: Dissolution test in water: Sample 10 was placed in 200% water, average value of 5 cycles PE: Low density polyethylene M120 EVA: Ethylene-vinyl acetate copolymer, (vinyl acetate 33% by weight) SA: Surfactant Octaoxyethylene-n-nonyl phenyl ether coating composition: The resin composition is PE and EVA, and SA is a percentage of the resin and a number added to the resin.

第4表のNo.1、2は3日後の水中溶出率が2年間保
存したことにより著しく増加しており被膜に欠陥部が生
じたことを示している。
No. of Table 4 Nos. 1 and 2 showed a remarkable increase in the dissolution rate in water after 3 days after being stored for 2 years, indicating that defects were formed in the film.

NO.3〜6は熔出率の変化がなく経時変化がないこと
を示している。欠陥部がどの様なものであるかを確認す
るために、10雌泣の肥料を発色液に1び分間浸潰して
からアルコールを用いて表面に付着した発色液を洗って
1粒づっ拡大鏡を用いて観察たところ被膜欠陥部は何れ
も内部に浸透した発色液で着色しており容易にその位置
が判別でき、欠陥の形は何れも1〜2側程度のヘアクラ
ツクであった。No.1は1勝泣、NO.2は1鎌雛こ
ヘアクラックが認められたがそれ以外の粒子には認めら
れなかった。No.3〜6ではこの様な亀裂は認められ
なかった。なお発色液はpージメチルアミノベンズアル
デヒド20夕、濃塩酸100の‘をアルコールに溶かし
1夕としたもので尿素と反応して黄色に着色するもので
ある。
NO. 3 to 6 indicate that there is no change in the dissolution rate and no change over time. In order to confirm what kind of defects there are, soak 10 drops of fertilizer in a coloring solution for 1 minute, wash off the coloring solution adhering to the surface with alcohol, and place each grain under a magnifying glass. As a result of observation using a microprocessor, all film defects were colored by the coloring liquid that had penetrated into the film, and their positions could be easily identified, and the defects were all hair cracks on one or two sides. No. 1 is 1 win, no. In No. 2, hair cracks were observed in one sickle, but no hair cracks were observed in other particles. No. No such cracks were observed in samples 3 to 6. The coloring solution is prepared by dissolving 20 parts of p-dimethylaminobenzaldehyde and 100 parts of concentrated hydrochloric acid in alcohol and leaving it for one night to react with urea to produce a yellow color.

以上初期溶出率と拡大鏡による観察の結果No.1、2
は保存中に亀裂が生成したがNo.3〜6は生成しない
ものであると判定した。
The results of the initial elution rate and observation using a magnifying glass are No. 1, 2
Although cracks formed during storage in No. Samples 3 to 6 were determined not to be produced.

実施例 6 本実施例はさらに広範囲の被覆組成の保存安定性の試験
結果を示す。
Example 6 This example further presents the results of testing the storage stability of a wider range of coating compositions.

第2図は実施例5の手法で2年間室温放置した場合の保
存安定性の試験結果である。図から明らかな様にエチレ
ン−酢酸ビニール共重合体の量が増加すると一般に保存
安定性が改善されることがわかる。ここで被膜組成:P
E十EVA十SA被覆率:PE+EVAが5重量%に設
定 EVA%:(EVA/PE+EVA)xloo(重量基
準)SA%:(SA/PE十EVA)xloo(重量基
準)PE:低密度ポリエチレン(M120)EVA:エ
チレン酢酸ビニール共重合体(M128、酢酸ビニール
33重量%)である。
FIG. 2 shows the storage stability test results when the sample was left at room temperature for two years using the method of Example 5. As is clear from the figure, it can be seen that as the amount of ethylene-vinyl acetate copolymer increases, storage stability generally improves. Here, film composition: P
E1EVA1SA Coverage rate: PE+EVA set to 5% by weight EVA%: (EVA/PE+EVA) xloo (weight basis) SA%: (SA/PE1EVA) xloo (weight basis) PE: Low density polyethylene (M120 ) EVA: Ethylene vinyl acetate copolymer (M128, vinyl acetate 33% by weight).

【図面の簡単な説明】[Brief explanation of the drawing]

第1図は、本発明に用いられる製造装置の一態様を示し
、第2図は、実施例4の試験結果を示す図である。 1・・・・・・噴流塔、2・・・・・・肥料投入口、3
・…・・排ガス噴出口、4・・・…流体ノズル、5…・
・・(被覆液供給用)ポンプ、7・・・・・・(被覆肥
料)抜出口、8・・・・・・熱交換器、9・・・・・・
オリフィス流量計、10・・・・・・ブロアー、11・
・・・・・(被覆液調製用)液タンク、T.・…・・熱
風温度計、T2・・・・・・被覆粒子用温度計、T3・
・・・・・排ガス温度計。 ÷ヒノ 鞠 矛之図
FIG. 1 shows one embodiment of the manufacturing apparatus used in the present invention, and FIG. 2 is a diagram showing the test results of Example 4. 1... Jet tower, 2... Fertilizer input port, 3
...Exhaust gas outlet, 4...Fluid nozzle, 5...
... (for coating liquid supply) pump, 7 ... (coated fertilizer) outlet, 8 ... heat exchanger, 9 ...
Orifice flow meter, 10...Blower, 11.
...Liquid tank (for coating liquid preparation), T. ...Hot air thermometer, T2...Thermometer for coated particles, T3.
...Exhaust gas thermometer. ÷Hino's picture of a spear

Claims (1)

【特許請求の範囲】 1 ポリオレフイン系樹脂と酢酸ビニール含有量20〜
40重量%のエチレン−酢酸ビニール共重合体との混合
物よりなり、且つ該混合物中のエチレン−酢酸ビニール
共重合体の含有量が少くとも10重量%である樹脂混合
物を主成分とし、該主成分に、更に、該主成分の0.0
1〜10重量%の界面活性剤を添加分散せしめた被覆材
料で完全に被覆された粒状肥料。 2 ポリオレフイン系樹脂と酢酸ビニール含有量20〜
40重量%のエチレン−酢酸ビニール共重合体との混合
物よりなり、且つ該混合物中のエチレン−酢酸ビニール
共重合体の含有量が少くとも10重量%である樹脂混合
物を主成分とし、該主成分に、更に、該主成分の0.0
1〜10重量%の界面活性剤を添加分散せしめた被覆材
料を溶剤に加えて得られた溶液を30℃以上で、且つ被
覆された肥料粒子が融着しない温度範囲に保持された肥
料粒子に噴霧すると同時に、上記樹脂溶液が噴霧された
肥料粒子に対して15m/sec以上の高速熱風流を当
て、上記溶液がゼリー状にゲル化する時間的余裕を与え
ずに瞬時に乾燥することを特徴とする上記樹脂被覆材で
被覆された肥料の製造方法。
[Claims] 1. Polyolefin resin and vinyl acetate content 20~
The main component is a resin mixture consisting of a mixture with 40% by weight of an ethylene-vinyl acetate copolymer, and the content of the ethylene-vinyl acetate copolymer in the mixture is at least 10% by weight; Furthermore, 0.0 of the main component
A granular fertilizer completely coated with a coating material in which 1 to 10% by weight of a surfactant is added and dispersed. 2 Polyolefin resin and vinyl acetate content 20~
The main component is a resin mixture consisting of a mixture with 40% by weight of an ethylene-vinyl acetate copolymer, and the content of the ethylene-vinyl acetate copolymer in the mixture is at least 10% by weight; Furthermore, 0.0 of the main component
A coating material in which 1 to 10% by weight of a surfactant is added and dispersed is added to a solvent, and the resulting solution is applied to fertilizer particles kept at 30°C or higher and within a temperature range where the coated fertilizer particles do not fuse. At the same time as the spraying, a high-speed hot air flow of 15 m/sec or more is applied to the fertilizer particles on which the resin solution has been sprayed, and the fertilizer particles are instantly dried without giving time for the solution to gel into a jelly. A method for producing a fertilizer coated with the above resin coating material.
JP53160192A 1978-12-27 1978-12-27 Coated fertilizer and its manufacturing method Expired JPS6037074B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP53160192A JPS6037074B2 (en) 1978-12-27 1978-12-27 Coated fertilizer and its manufacturing method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP53160192A JPS6037074B2 (en) 1978-12-27 1978-12-27 Coated fertilizer and its manufacturing method

Publications (2)

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JPS5590495A JPS5590495A (en) 1980-07-09
JPS6037074B2 true JPS6037074B2 (en) 1985-08-23

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JP53160192A Expired JPS6037074B2 (en) 1978-12-27 1978-12-27 Coated fertilizer and its manufacturing method

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006265061A (en) * 2005-03-25 2006-10-05 Sumitomo Chemical Co Ltd Granulated fertilizer composition
US11001539B2 (en) 2015-09-11 2021-05-11 Sumitomo Chemical Company, Limited Coated granular fertilizer, method for producing coated granular fertilizer, and fertilizer compostion

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0692275B2 (en) * 1986-04-01 1994-11-16 旭化成工業株式会社 Coated granular fertilizer
JPH01215783A (en) * 1988-02-23 1989-08-29 Chisso Corp Coated granular fertilizer
EP0337298B1 (en) * 1988-04-06 1993-07-07 Sumitomo Chemical Company, Limited Coated granular fertilizer composition and its production
EP0976699A4 (en) 1997-02-19 2009-06-03 Chisso Asahi Fertilizer Granular fertilizer coated with decomposable coating film and process for producing the same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006265061A (en) * 2005-03-25 2006-10-05 Sumitomo Chemical Co Ltd Granulated fertilizer composition
US11001539B2 (en) 2015-09-11 2021-05-11 Sumitomo Chemical Company, Limited Coated granular fertilizer, method for producing coated granular fertilizer, and fertilizer compostion

Also Published As

Publication number Publication date
JPS5590495A (en) 1980-07-09

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