JP2003252913A - Method for manufacturing polymer particle - Google Patents
Method for manufacturing polymer particleInfo
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- JP2003252913A JP2003252913A JP2002057583A JP2002057583A JP2003252913A JP 2003252913 A JP2003252913 A JP 2003252913A JP 2002057583 A JP2002057583 A JP 2002057583A JP 2002057583 A JP2002057583 A JP 2002057583A JP 2003252913 A JP2003252913 A JP 2003252913A
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- suspension
- average particle
- volume average
- particle diameter
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- Polymerisation Methods In General (AREA)
Abstract
Description
【発明の詳細な説明】
【０００１】
【発明の属する技術分野】本発明は、重合体粒子の製造
方法に関する。更に詳しくは、本発明は、所望範囲の体
積平均粒子径の重合体粒子の製造方法に関する。本発明
の製造方法により得られた重合体粒子は、スペーサー、
光拡散剤、滑り性付与剤、トナー、塗料のつや消し剤、
機能性担体等として使用できる。
【０００２】
【従来の技術】微細な重合体粒子は様々な方面で必要と
されている。特に、粒子の大きさが１〜３μｍであり、
粒度分布が均一な重合体粒子は、スペーサー、光拡散
剤、滑り性付与剤、トナー等に適しており、これらの分
野で広く要望されている。ところが、この要望を満たす
粒子を提供するには困難があった。
【０００３】例えば、微細な重合体粒子を得るためには
通常乳化重合法によればよいと考えるであろう。ところ
が、乳化重合法によったのでは、粒子の大きさが通常１
μｍ以下の微細なものとなってしまう。また、通常の懸
濁重合法によっても１〜３μｍの粒子を得ることは難し
く、粒度分布を均一にすることも難しい。
【０００４】他方、乳化液、懸濁液等を作る装置とし
て、高い圧力の下にある液体を流して、液流を互いに衝
突あるいは所定の平面部に衝突させてその衝撃によりそ
の中に含まれている懸濁粒子を粉砕して微細化し、これ
によって大きさの揃った微細粒子の懸濁液を作ることを
原理とするナノマイザー、ハーモナイザー又はマイクロ
フルイダイザー等の装置がある。
【０００５】特開平４−１５６５５５号公報は、上記の
液流同士の衝突によって懸濁粒子を微細化して懸濁液を
作り、この懸濁液を懸濁重合させて静電現像用のトナー
を作る方法を開示している。この公報によれば、エチレ
ン系単量体と、この単量体に可溶な重合開始剤と、界面
活性剤と、分散安定剤とを水性媒体中に加え、撹拌して
体積平均粒子径が３０〜４０μｍの単量体液滴の１次懸
濁液を作り、この１次懸濁液を加圧下に複数の流れに分
けて流し、こうして得た液流同士を衝突させて単量体粒
子を更に微細化して２次懸濁液を作り、その後２次懸濁
液を懸濁重合させて微細な重合体粒子を得ている。
【０００６】上記公報が開示する技術は、界面活性剤を
臨界ミセル濃度の０．５〜２．０倍という程の大量に使
用することを必要としている。ところが、このような大
量の界面活性剤を用いて２次懸濁液を作ったのでは、懸
濁粒子の大きさがなお不揃いとなり、従って狭い粒度分
布を持ち、大きさの揃った微細な重合体粒子が得られな
いことが判明した。そこで、大きさの揃った微細な重合
体を作るには、更に別な製造方法を開発することが必要
となり、その改良法として特開平７−２９２０２５号公
報に記載の技術が生まれた。
【０００７】この技術は、大量の界面活性剤を使用せず
に、界面活性剤の使用量を臨界ミセル濃度の０．５倍以
下とし、高速回転撹拌装置によって単量体を重量平均粒
子径が３〜１０μｍの油滴として１次懸濁液を作り、次
いでこれを加圧下液体同士を衝突させると微細化とは逆
に粒子の合着が起り、これによって粒子が逆に大きくな
り、その結果粒径が４〜１００μｍの大きさの範囲内で
あって、かつ所望の狭い領域内に局限された粒子が得ら
れるものであり、その合着の程度、すなわち得られる粒
径は１次懸濁液に加える圧力の加減により容易に調節で
きるという方法である。
【０００８】
【発明が解決しようとする課題】しかしながら上記公報
で示される方法では、重合体粒子の粒度分布を均一にす
ることはできても、体積平均粒子径を１〜３μｍ程度の
大きさにすることは難しかった。
【０００９】
【課題を解決するための手段】かくして本発明によれ
ば、スチレン系単量体又はスチレン系単量体と他の共重
合性単量体との単量体混合物、該単量体又は単量体混合
物に可溶な重合開始剤、両性界面活性剤及び無機系分散
安定剤を水性媒体中に加えて体積平均粒子径が３〜２０
μｍの単量体の１次懸濁液を作り、該１次懸濁液を加圧
下、ノズルから噴出させて２次懸濁液を作り、該２次懸
濁液を重合させて体積平均粒子径が１〜３μｍで、変動
係数が２５％以下である樹脂粒子を得ることを特徴とす
る重合体粒子の製造方法が提供される。
【００１０】
【発明の実施の形態】本発明では単量体として、スチレ
ン系単量体又はスチレン系単量体と他の共重合性単量体
との単量体混合物を使用する。ここで、スチレン系単量
体は、単量体全量に対して５０重量％以上であることが
好ましい。また、本発明におけるスチレン系単量体とし
ては、スチレン、ｐ−メチルスチレン、ｐ−クロロスチ
レン等が挙げられる。他の共重合性単量体としては、例
えば、アクリル酸エチル、アクリル酸ブチル、アクリル
酸２−エチルヘキシル等のアクリル酸エステル系単量
体；メタクリル酸メチル、メタクリル酸エチル、メタク
リル酸ブチル等のメタクリル酸エステル系単量体；ポリ
エチレングリコールモノ（メタ）アクリレート、メチル
ビニルエーテル等のアルキルビニルエーテル；酢酸ビニ
ル、酪酸ビニル等のビニルエステル系単量体；Ｎ−メチ
ルアクリルアミド、Ｎ−エチルアクリルアミド等のＮ−
アルキル置換アクリルアミド；アクリロニトリル、メタ
アクリロニトリル等のニトリル系単量体；ジビニルベン
ゼン、エチレングリコール（メタ）アクリレート、トリ
メチロールプロパントリ（メタ）アクリレート等の多官
能性単量体等が挙げられる。これらの単量体は必要に応
じて、単独又は２種類以上を混合して用いることができ
る。また、この単量体中に分散あるいは溶解可能な染料
及び顔料等の添加物を添加することも可能である。な
お、上記単量体において、（メタ）アクリレートとは、
アクリレート又はメタクリレートを意味する。
【００１１】懸濁重合時の単量体と水性媒体との比率
（重量比）は、１／１０〜１／２の範囲であることが好
ましい。１／１０より単量体が少なくなると、生産性が
悪くなるため好ましくない。また、１／２より単量体が
多くなると、体積平均粒子径を３μｍ以下に維持するこ
とが困難となるため好ましくない。
【００１２】ここで、水性媒体としては、水、水と水溶
性有機化合物（例えば、低級アルコール）との混合物が
挙げられる。
【００１３】本発明における重合開始剤は、上記単量体
に可溶な一般に用いられる油溶性重合触媒であれば特に
限定されることなく使用でき、例えば過酸化ベンゾイ
ル、過酸化ラウロイル、ｔ−ブチルペルオキシオクトエ
ート等の過酸化物系触媒、アゾビスイソブチロニトリ
ル、アゾビスイソバレロニトリル等のアゾ系触媒が使用
できる。
【００１４】上記単量体にこれら重合開始剤を溶解し、
無機系分散安定剤と両性界面活性剤又は必要に応じて添
加される分散安定補助剤等を含む水性媒体に添加した
後、１次懸濁液が作成される。
【００１５】無機系分散安定剤としては、硫酸バリウ
ム、硫酸カルシウム、炭酸マグネシウム、リン酸カルシ
ウム、ピロリン酸マグネシウム等の難水溶性無機塩及
び、酸化ケイ素、酸化チタン等の金属酸化物等が挙げら
れる。この内、リン酸カルシウム、ピロリン酸マグネシ
ウム等の難水溶性無機塩が好ましい。
【００１６】両性界面活性剤としては、例えば、ラウリ
ルベタイン、ステアリルベタイン、ジメチルアルキルラ
ウリルベタイン、ジメチルアルキルヤシベタイン、ヤシ
油脂肪酸アミドプロピルジメチルアミノ酢酸ベタイン等
のベタイン型両性界面活性剤、Ｎ−ヤシ油脂肪酸アシル
−Ｎ−カルボキシメチル−Ｎ−ヒドロキシエチルエチレ
ンジアミンナトリウム等のイミダゾリン型両性界面活性
剤が挙げられる。この内、ベタイン型両性界面活性剤が
好ましい。
【００１７】更に、アニオン系界面活性剤を併用しても
よい。アニオン系界面活性剤を使用することで、１次及
び２次懸濁液の懸濁状態をより安定化することができ
る。アニオン系界面活性剤の使用量は、使用する界面活
性剤の種類に応じて適宜調整され、例えば、両性界面活
性剤／アニオン系界面活性剤＝１００／０〜５０／５０
（重量比）の範囲が挙げられる。
【００１８】アニオン系界面活性剤としては、例えばラ
ウリル硫酸ナトリウム、ドデシルベンゼンスルホン酸ナ
トリウム、ポリオキシエチレンラウリルエーテル硫酸ナ
トリウム、ジオクチルスルホコハク酸ナトリウムが挙げ
られる。
【００１９】両性界面活性剤は、その種類にもよるが、
臨界ミセル濃度を超えない範囲で使用することが好まし
い。臨界ミセル濃度を超えて使用した場合、懸濁重合時
に乳化重合が生じやすくなり、所望の粒径以外の粒子が
生じることがある。両性界面活性剤は、臨界ミセル濃度
の０．５倍以下で使用することが好ましく、０．０２〜
０．３倍の範囲で使用することが特に好ましい。臨界ミ
セル濃度とは、界面活性剤の分子が集合して水溶液中で
ミセルと呼ばれるコロイド大の会合体を形成するに至る
濃度で、界面活性剤に固有な値である。
【００２０】本発明において、１次懸濁液を作るには、
剪断力によって単量体を分散させる機構の装置が使用で
きる。装置としては、通常の撹拌装置あるいはホモミキ
サー等の高速回転式撹拌機を使用し、この装置を所定の
撹拌速度で所定時間撹拌する。１次懸濁液では、単量体
を体積平均粒子径が３〜２０μｍの液滴とすることが必
要とされる。体積平均粒子径を３μｍ未満としても２次
懸濁液中の液滴の体積平均粒子径を１μｍ以下とするこ
とはできないので、１次懸濁液で３μｍ以下にする必要
はない。一方、２０μｍより大きい場合、２次懸濁液中
の液滴の体積平均粒子径を１〜３μｍとすることが困難
である。
【００２１】本発明では、体積平均粒子径が３〜２０μ
ｍの液滴とした１次懸濁液を、加圧噴射することにより
体積平均粒子径が１〜３μｍの液滴を含む２次懸濁液を
得る。加圧噴射するために使用される装置としては、例
えばノズルから懸濁液を噴射するタイプのプロセッサー
を接続した装置、懸濁液を加圧下で液同士あるいは液を
所定の平面に衝突させるタイプの装置を使用することが
できる。具体的な装置としては、ナノマイザー、ハーモ
ナイザー、マイクロフルイダイザー、アルティマイザー
等が挙げられる。
【００２２】こうして得られた２次懸濁液を懸濁重合さ
せる。このとき、２次懸濁液は既に重合開始剤を含んで
いるので、例えばこの懸濁液を加熱するだけで重合を開
始させることができる。加熱条件は重合開始剤、単量体
の種類に応じて適当な温度にするが、通常は４０〜１０
０℃、０．５〜１０時間の範囲内であり、好ましくは５
０〜９０℃、１〜８時間の範囲内である。重合させる
と、単量体は２次懸濁液中の体積平均粒子径そのままで
重合体となるので、大きさのよく揃った重合体粒子が得
られる。
【００２３】重合後は、濾過、遠心分離等によって重合
体粒子を水性媒体から分離し、水洗又は溶剤で洗浄後、
乾燥して粉体として使用することが好ましい。上記本発
明の製造方法により得られた重合体粒子は、体積平均粒
子径が１〜３μｍでかつ変動係数が１０〜２５％である
領域内に粒子径を有しており、所望の範囲内に体積平均
粒子径の揃った重合体粒子を得ることができる。なお、
本発明において体積平均粒子径は、実施例に記載の方法
により測定した平均粒子径を意味する。
【００２４】本発明の製造方法により得られた重合体粒
子は、スペーサー、光拡散剤、滑り性付与剤、トナー、
塗料のつや消し剤、機能性担体等の原料として又はその
まま使用することができる。
【００２５】
【実施例】次に、実施例により本発明を具体的に説明す
るが、本発明は以下の実施例には限定されない。
【００２６】体積平均粒子径及び変動係数は、レーザー
散乱・回折式粒度分布測定装置ＬＳ２３０（ベックマン
コールター社製）により測定した。サンプルの分散媒と
して水を用い、サンプルの屈折率は重合体の屈折率を用
いた。ここでいう体積平均粒子径は、算術平均により求
められた数値である。また、変動係数とは次式から求め
られる数値であり、データの分布幅を表すものである。
変動係数（％）＝標準偏差×１００／体積平均粒子径
【００２７】実施例１
アゾビス−Ｎ，Ｎ−ジメチルバレロニトリル１ｇを、ス
チレン９０ｇとジビニルベンゼン１０ｇ（純度８２％）
との混合液に溶解し、ラウリル硫酸ナトリウム０．１５
ｇ、ジメチルアルキルラウリルベタイン水溶液（有効成
分３５％）１．３ｇ、複分解ピロリン酸マグネシウム１
５ｇを含む水５００ｇに加え、ＴＫホモミキサー（特殊
機化社製）にて、液滴の体積平均粒子径が８μｍ程度と
なるよう１次懸濁液を調製した。
【００２８】次いで、ナノマイザーＬＡ−３３（ナノマ
イザー社製）にノズル型プロセッサー（ＬＮＰ−２０／
３００）を接続して、１次懸濁液を３００ｋｇ／ｃｍ2
の圧力下に１回通して２次懸濁液を作った。
【００２９】この２次懸濁液を撹拌機及び温度計を備え
た重合器に入れ、緩やかな撹拌下で６０℃で８時間懸濁
重合させて重合体粒子を得た。得られた重合体粒子の体
積平均粒子径は２．２μｍで、変動係数は１８．９％で
あり、粒度分布が狭い領域内に局限されていて、粒子の
大きさがよく揃ったものであった。
【００３０】実施例２
アゾビス−Ｎ，Ｎ−ジメチルバレロニトリル１ｇを、ス
チレン６０ｇ、メタクリル酸メチル３４ｇとジビニルベ
ンゼン６ｇ（純度８２％）との混合液に溶解し、ドデシ
ルベンゼンスルホン酸ナトリウム０．５ｇ、Ｎ−ヤシ油
脂肪酸アシル−Ｎ−カルボキシメチル−Ｎ−ヒドロキシ
エチルエチレンジアミンナトリウム水溶液（有効成分４
０％）０．７５ｇ、複分解ピロリン酸マグネシウム１５
ｇを含む水５００ｇに加え、ＴＫホモミキサー（特殊機
化社製）にて、液滴の体積平均粒子径が１５μｍ程度と
なるよう１次懸濁液を調製した。
【００３１】次いで、ナノマイザーＬＡ−３３（ナノマ
イザー社製）に衝突型プロセッサー（ＬＤ−５００）を
接続して、１次懸濁液を７００ｋｇ／ｃｍ2の圧力下に
１回通して２次懸濁液を作った。
【００３２】この２次懸濁液を撹拌機及び温度計を備え
た重合器に入れ、緩やかな撹拌下で５０℃で８時間懸濁
重合させて重合体粒子を得た。得られた重合体粒子の体
積平均粒子径は２．３μｍで、変動係数は２１．８％で
あり、粒度分布が狭い領域内に局限されていて、粒子の
大きさがよく揃ったものであった。
【００３３】実施例３
アゾビスイソブチロニトリル１ｇを、スチレン６３ｇと
ジビニルベンゼン３７ｇ（純度８２％）との混合液に溶
解し、ラウリル硫酸ナトリウム０．３５ｇ、ヤシ油脂肪
酸アミドプロピルジメチルアミノ酢酸ベタイン水溶液
（有効成分３０％）１．２ｇ、複分解ピロリン酸マグネ
シウム２５ｇを含む水７００ｇに加え、ＴＫホモミキサ
ー（特殊機化社製）にて、液滴の体積平均粒子径が５μ
ｍ程度となるよう１次懸濁液を調製した。
【００３４】次いで、マイクロフルイダイザーＭ１１０
Ｅ／Ｈ−Ｓ（みずほ工業社製）に、１次懸濁液を１００
ｋｇ／ｃｍ2の圧力下に１回通して２次懸濁液を作っ
た。
【００３５】この２次懸濁液を撹拌機及び温度計を備え
た重合器に入れ、緩やかな撹拌下で７０℃で８時間懸濁
重合させて重合体粒子を得た。得られた重合体粒子の体
積平均粒子径は１．９μｍで、変動係数は１７．５％で
あり、粒度分布が狭い領域内に局限されていて、粒子の
大きさがよく揃ったものであった。
【００３６】比較例１
ジメチルアルキルラウリルベタイン水溶液を加えなかっ
たこと以外は実施例１と同様にして重合体粒子を得た。
得られた重合体粒子の体積平均粒子径は６．３μｍで、
変動係数は２３．５％であり、体積平均粒子径が大きか
った。
【００３７】比較例２
１次懸濁液の液滴の体積平均粒子径を約３０μｍとした
こと以外は実施例１と同様にして２次懸濁液を得た。
【００３８】この２次懸濁液を撹拌機及び温度計を備え
た重合器に入れ、緩やかな撹拌下で６０℃で５時間懸濁
重合させて重合体粒子を得た。得られた重合体粒子の体
積平均粒子径は５．６μｍで、変動係数は２０．５％で
あり、体積平均粒子径が大きかった。
【００３９】比較例３
実施例１と同様にして得られた１次懸濁液を、更にＴＫ
ホモミキサーにて１２０００ｒｐｍで１０分間処理し、
得られた懸濁液を撹拌機及び温度計を備えた重合器に入
れ、緩やかな撹拌下で６０℃で５時間懸濁重合させて重
合体粒子を得た。得られた重合体粒子の体積平均粒子径
は４．２μｍで、変動係数は３５．８％であり、体積平
均粒子径が大きいと共に粒子の大きさが不揃いであっ
た。
【００４０】
【発明の効果】本発明の製造方法によれば、懸濁重合で
粒度分布が均一な１〜３μｍの体積平均粒子径の重合体
粒子を得ることができる。この粒子は大きさが揃ってい
るために、スペーサー、滑り性付与剤、トナー、光拡散
剤、塗料のつや消し剤、機能性担体等として使用するに
好適なものとなる。Description: TECHNICAL FIELD The present invention relates to a method for producing polymer particles. More specifically, the present invention relates to a method for producing polymer particles having a volume average particle diameter in a desired range. Polymer particles obtained by the production method of the present invention, a spacer,
Light diffusers, slippers, toners, paint matting agents,
It can be used as a functional carrier or the like. [0002] Fine polymer particles are required in various fields. In particular, the size of the particles is 1-3 μm,
Polymer particles having a uniform particle size distribution are suitable for spacers, light diffusing agents, slipperiness imparting agents, toners, and the like, and are widely demanded in these fields. However, it has been difficult to provide particles satisfying this demand. For example, in order to obtain fine polymer particles, it may be considered that an emulsion polymerization method is usually used. However, according to the emulsion polymerization method, the particle size is usually 1
It will be finer than μm. Also, it is difficult to obtain particles having a size of 1 to 3 μm by a usual suspension polymerization method, and it is also difficult to make the particle size distribution uniform. On the other hand, as an apparatus for producing an emulsion, a suspension or the like, liquids under high pressure are caused to flow, and the liquid streams collide with each other or collide with a predetermined flat portion, and are contained therein by the impact. There is a device such as a nanomizer, a harmonizer, or a microfluidizer which is based on the principle of pulverizing and suspending the suspended particles to form a suspension of fine particles having a uniform size. Japanese Patent Application Laid-Open No. 4-156555 discloses that a suspension is formed by making suspended particles fine by collision of the liquid streams described above, and the suspension is subjected to suspension polymerization to prepare a toner for electrostatic development. It discloses how to make it. According to this publication, an ethylene-based monomer, a polymerization initiator soluble in this monomer, a surfactant, and a dispersion stabilizer are added to an aqueous medium, and the volume average particle diameter is stirred by stirring. A primary suspension of monomer droplets having a size of 30 to 40 μm is prepared, and this primary suspension is divided into a plurality of streams under pressure, and the thus obtained streams are caused to collide with each other to form monomer particles. The suspension is further refined to form a secondary suspension, and then the secondary suspension is subjected to suspension polymerization to obtain fine polymer particles. The technique disclosed in the above publication requires the use of a surfactant in a large amount of 0.5 to 2.0 times the critical micelle concentration. However, when a secondary suspension is prepared using such a large amount of surfactant, the size of the suspended particles is still uneven, and therefore, the fine particles have a narrow particle size distribution and uniform size. It was found that no coalesced particles could be obtained. Therefore, in order to produce a fine polymer having a uniform size, it is necessary to develop still another production method, and the technique described in Japanese Patent Application Laid-Open No. 7-292025 has been developed as an improved method. In this technique, the amount of the surfactant is reduced to 0.5 times or less of the critical micelle concentration without using a large amount of the surfactant, and the monomer is used to reduce the weight-average particle diameter by a high-speed rotation stirrer. When a primary suspension is formed as an oil droplet of 3 to 10 μm, and the liquid is then crushed with liquid under pressure, coalescence of the particles occurs, contrary to the miniaturization. Particles having a particle size in the range of 4 to 100 μm and localized within a desired narrow area are obtained, and the degree of coalescence, that is, the obtained particle size is determined by primary suspension. This is a method that can be easily adjusted by adjusting the pressure applied to the liquid. [0008] However, according to the method disclosed in the above publication, even though the particle size distribution of the polymer particles can be made uniform, the volume average particle diameter is reduced to about 1 to 3 μm. It was difficult to do. According to the present invention, there is provided a styrene-based monomer or a monomer mixture of a styrene-based monomer and another copolymerizable monomer, Alternatively, a polymerization initiator soluble in a monomer mixture, an amphoteric surfactant and an inorganic dispersion stabilizer are added to an aqueous medium to give a volume average particle diameter of 3 to 20.
A primary suspension of a monomer having a size of μm is prepared, and the primary suspension is ejected from a nozzle under pressure to form a secondary suspension, and the secondary suspension is polymerized to obtain a volume average particle. A method for producing polymer particles is provided, wherein resin particles having a diameter of 1 to 3 μm and a coefficient of variation of 25% or less are obtained. DETAILED DESCRIPTION OF THE INVENTION In the present invention, a styrene monomer or a monomer mixture of a styrene monomer and another copolymerizable monomer is used as a monomer. Here, the styrene-based monomer is preferably 50% by weight or more based on the total amount of the monomer. The styrene monomer in the present invention includes styrene, p-methylstyrene, p-chlorostyrene and the like. Other copolymerizable monomers include, for example, acrylate monomers such as ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate; methacryl such as methyl methacrylate, ethyl methacrylate, and butyl methacrylate; Acid ester monomers; alkyl vinyl ethers such as polyethylene glycol mono (meth) acrylate and methyl vinyl ether; vinyl ester monomers such as vinyl acetate and vinyl butyrate; N-methyl amides such as N-methylacrylamide and N-ethylacrylamide
Alkyl-substituted acrylamide; nitrile monomers such as acrylonitrile and methacrylonitrile; and polyfunctional monomers such as divinylbenzene, ethylene glycol (meth) acrylate, and trimethylolpropane tri (meth) acrylate. These monomers can be used alone or as a mixture of two or more, if necessary. It is also possible to add additives such as dyes and pigments which can be dispersed or dissolved in the monomer. In the above monomer, (meth) acrylate is
Means acrylate or methacrylate. The ratio (weight ratio) of the monomer to the aqueous medium during suspension polymerization is preferably in the range of 1/10 to 1/2. If the amount of the monomer is less than 1/10, the productivity is deteriorated, which is not preferable. On the other hand, when the amount of the monomer is more than 1/2, it is difficult to maintain the volume average particle diameter at 3 μm or less, which is not preferable. Here, examples of the aqueous medium include water and a mixture of water and a water-soluble organic compound (for example, lower alcohol). The polymerization initiator used in the present invention can be used without any particular limitation as long as it is a generally used oil-soluble polymerization catalyst soluble in the above-mentioned monomers. For example, benzoyl peroxide, lauroyl peroxide, t-butyl A peroxide catalyst such as peroxyoctoate and an azo catalyst such as azobisisobutyronitrile and azobisisovaleronitrile can be used. These polymerization initiators are dissolved in the above monomer,
After being added to the aqueous medium containing the inorganic dispersion stabilizer and the amphoteric surfactant or the dispersion stabilizing aid optionally added, a primary suspension is prepared. Examples of the inorganic dispersion stabilizer include poorly water-soluble inorganic salts such as barium sulfate, calcium sulfate, magnesium carbonate, calcium phosphate and magnesium pyrophosphate, and metal oxides such as silicon oxide and titanium oxide. Of these, poorly water-soluble inorganic salts such as calcium phosphate and magnesium pyrophosphate are preferred. Examples of the amphoteric surfactant include betaine-type amphoteric surfactants such as lauryl betaine, stearyl betaine, dimethyl alkyl lauryl betaine, dimethyl alkyl coco betaine, and coconut fatty acid amidopropyl dimethylamino acetate betaine, and N-coconut oil. Examples include imidazoline-type amphoteric surfactants such as fatty acid acyl-N-carboxymethyl-N-hydroxyethylethylenediamine sodium. Of these, betaine-type amphoteric surfactants are preferred. Further, an anionic surfactant may be used in combination. By using an anionic surfactant, the suspension state of the primary and secondary suspensions can be further stabilized. The amount of the anionic surfactant used is appropriately adjusted depending on the type of the surfactant used. For example, amphoteric surfactant / anionic surfactant = 100/0 to 50/50
(Weight ratio). Examples of the anionic surfactant include sodium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium polyoxyethylene lauryl ether sulfate, and sodium dioctyl sulfosuccinate. The amphoteric surfactant depends on its type,
It is preferable to use it within a range not exceeding the critical micelle concentration. When used above the critical micelle concentration, emulsion polymerization tends to occur during suspension polymerization, and particles other than the desired particle size may be generated. The amphoteric surfactant is preferably used at 0.5 times or less the critical micelle concentration,
It is particularly preferable to use it in a range of 0.3 times. The critical micelle concentration is a concentration at which surfactant molecules are assembled to form a colloid-sized aggregate called a micelle in an aqueous solution, and is a value specific to the surfactant. In the present invention, to make a primary suspension,
An apparatus having a mechanism for dispersing a monomer by shearing force can be used. As a device, a normal stirring device or a high-speed rotary stirrer such as a homomixer is used, and the device is stirred at a predetermined stirring speed for a predetermined time. In the primary suspension, it is necessary that the monomer be formed into droplets having a volume average particle diameter of 3 to 20 μm. Even if the volume average particle size is less than 3 μm, the volume average particle size of the droplets in the secondary suspension cannot be reduced to 1 μm or less, so that the primary suspension need not be 3 μm or less. On the other hand, if it is larger than 20 μm, it is difficult to make the volume average particle diameter of the droplets in the secondary suspension 1 to 3 μm. In the present invention, the volume average particle diameter is 3 to 20 μm.
The secondary suspension containing droplets having a volume average particle diameter of 1 to 3 μm is obtained by injecting the primary suspension in the form of m droplets under pressure. Examples of the device used for pressurized jetting include a device connected to a processor of a type for jetting a suspension from a nozzle, and a type of a device for colliding a suspension with liquids or a liquid against a predetermined plane under pressure. The device can be used. Specific examples of the apparatus include a nanomizer, a harmonizer, a microfluidizer, and an optimizer. The secondary suspension thus obtained is subjected to suspension polymerization. At this time, since the secondary suspension already contains a polymerization initiator, for example, polymerization can be started only by heating this suspension. The heating condition is set to an appropriate temperature depending on the type of the polymerization initiator and the type of the monomer.
0 ° C., in the range of 0.5 to 10 hours, preferably 5
0-90 ° C, 1-8 hours. When polymerized, the monomer becomes a polymer with the volume average particle diameter in the secondary suspension as it is, so that polymer particles having a uniform size can be obtained. After polymerization, the polymer particles are separated from the aqueous medium by filtration, centrifugation, etc., washed with water or washed with a solvent,
It is preferable to dry and use it as a powder. The polymer particles obtained by the production method of the present invention have a volume average particle diameter of 1 to 3 μm and a variation coefficient of 10 to 25%. Polymer particles having a uniform volume average particle diameter can be obtained. In addition,
In the present invention, the volume average particle diameter means an average particle diameter measured by the method described in Examples. The polymer particles obtained by the production method of the present invention include a spacer, a light diffusing agent, a slipping agent, a toner,
It can be used as a raw material for a matting agent, a functional carrier or the like of a paint or as it is. Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples. The volume average particle diameter and the coefficient of variation were measured with a laser scattering / diffraction type particle size distribution analyzer LS230 (manufactured by Beckman Coulter). Water was used as the dispersion medium of the sample, and the refractive index of the sample was the refractive index of the polymer. Here, the volume average particle diameter is a numerical value obtained by arithmetic mean. The variation coefficient is a numerical value obtained from the following equation, and represents the distribution width of data. Coefficient of variation (%) = standard deviation × 100 / volume average particle size Example 1 1 g of azobis-N, N-dimethylvaleronitrile was mixed with 90 g of styrene and 10 g of divinylbenzene (purity 82%).
Dissolved in a mixture with 0.15 g of sodium lauryl sulfate
g, aqueous solution of dimethyl alkyl lauryl betaine (35% of active ingredient) 1.3 g, metathesized magnesium pyrophosphate 1
In addition to 500 g of water containing 5 g, a primary suspension was prepared using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.) so that the volume average particle diameter of the droplets was about 8 μm. Next, a nozzle type processor (LNP-20 / Nanomizer LA-33, manufactured by Nanomizer Co., Ltd.) was used.
300) and connect the primary suspension to 300 kg / cm 2
A second suspension was made under a pressure of 1 to make a second suspension. This secondary suspension was put into a polymerization vessel equipped with a stirrer and a thermometer, and subjected to suspension polymerization at 60 ° C. for 8 hours under gentle stirring to obtain polymer particles. The volume average particle diameter of the obtained polymer particles was 2.2 μm, the coefficient of variation was 18.9%, the particle size distribution was confined within a narrow region, and the particle sizes were well-aligned. Was. Example 2 1 g of azobis-N, N-dimethylvaleronitrile was dissolved in a mixture of 60 g of styrene, 34 g of methyl methacrylate and 6 g of divinylbenzene (purity 82%), and 0.5 g of sodium dodecylbenzenesulfonate was dissolved. , N-coconut fatty acid acyl-N-carboxymethyl-N-hydroxyethylethylenediamine sodium aqueous solution (active ingredient 4
0%) 0.75 g, metathesized magnesium pyrophosphate 15
g of water containing 500 g, and a TK homomixer (manufactured by Tokushu Kika Co., Ltd.) was used to prepare a primary suspension so that the volume average particle diameter of the droplets was about 15 μm. Next, a collision type processor (LD-500) was connected to the Nanomizer LA-33 (manufactured by Nanomizer), and the primary suspension was passed once under a pressure of 700 kg / cm 2 to perform secondary suspension. I made a liquid. This secondary suspension was put into a polymerization vessel equipped with a stirrer and a thermometer, and subjected to suspension polymerization at 50 ° C. for 8 hours under gentle stirring to obtain polymer particles. The volume average particle diameter of the obtained polymer particles was 2.3 μm, the coefficient of variation was 21.8%, and the particle size distribution was confined within a narrow region, and the particle sizes were well uniform. Was. Example 3 1 g of azobisisobutyronitrile was dissolved in a mixture of 63 g of styrene and 37 g of divinylbenzene (purity: 82%), 0.35 g of sodium lauryl sulfate, coconut oil fatty acid amidopropyldimethylaminoacetic acid betaine In addition to 1.2 g of an aqueous solution (active ingredient 30%) and 700 g of water containing 25 g of double-decomposed magnesium pyrophosphate, the volume average particle diameter of the droplets was 5 μm using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.).
A primary suspension was prepared so as to be about m. Next, the microfluidizer M110
E / HS (manufactured by Mizuho Industry Co., Ltd.),
A second suspension was made under a pressure of kg / cm 2 once. This secondary suspension was put into a polymerization vessel equipped with a stirrer and a thermometer, and subjected to suspension polymerization at 70 ° C. for 8 hours under gentle stirring to obtain polymer particles. The volume average particle diameter of the obtained polymer particles was 1.9 μm, the coefficient of variation was 17.5%, the particle size distribution was confined within a narrow region, and the particle sizes were well-uniform. Was. Comparative Example 1 Polymer particles were obtained in the same manner as in Example 1 except that no aqueous dimethylalkyllaurylbetaine solution was added.
The volume average particle diameter of the obtained polymer particles is 6.3 μm,
The coefficient of variation was 23.5%, and the volume average particle size was large. Comparative Example 2 A secondary suspension was obtained in the same manner as in Example 1 except that the volume average particle diameter of the droplets of the primary suspension was about 30 μm. This secondary suspension was put into a polymerization vessel equipped with a stirrer and a thermometer, and subjected to suspension polymerization at 60 ° C. for 5 hours under gentle stirring to obtain polymer particles. The volume average particle diameter of the obtained polymer particles was 5.6 μm, the coefficient of variation was 20.5%, and the volume average particle diameter was large. Comparative Example 3 The primary suspension obtained in the same manner as in Example 1 was further treated with TK
Treated at 12000 rpm for 10 minutes with a homomixer,
The obtained suspension was placed in a polymerization vessel equipped with a stirrer and a thermometer, and subjected to suspension polymerization at 60 ° C. for 5 hours under gentle stirring to obtain polymer particles. The volume average particle diameter of the obtained polymer particles was 4.2 μm, the coefficient of variation was 35.8%, and the volume average particle diameter was large and the particle sizes were not uniform. According to the production method of the present invention, polymer particles having a volume average particle diameter of 1 to 3 μm having a uniform particle size distribution can be obtained by suspension polymerization. Since the particles have a uniform size, they are suitable for use as a spacer, a slip imparting agent, a toner, a light diffusing agent, a matting agent for paint, a functional carrier, and the like.
Claims (1)
と他の共重合性単量体との単量体混合物、該単量体又は
単量体混合物に可溶な重合開始剤、両性界面活性剤及び
無機系分散安定剤を水性媒体中に加えて体積平均粒子径
が３〜２０μｍの単量体の１次懸濁液を作り、該１次懸
濁液を加圧下、ノズルから噴出させて２次懸濁液を作
り、該２次懸濁液を重合させて体積平均粒子径が１〜３
μｍで、変動係数が２５％以下である樹脂粒子を得るこ
とを特徴とする重合体粒子の製造方法。Claims: 1. A monomer mixture of a styrene monomer or a styrene monomer and another copolymerizable monomer, and soluble in the monomer or the monomer mixture. A polymerization initiator, an amphoteric surfactant and an inorganic dispersion stabilizer are added to an aqueous medium to prepare a primary suspension of a monomer having a volume average particle diameter of 3 to 20 μm. The secondary suspension is ejected from the nozzle under pressure to form a secondary suspension, and the secondary suspension is polymerized to have a volume average particle diameter of 1 to 3.
A method for producing polymer particles, wherein resin particles having a μm and a coefficient of variation of 25% or less are obtained.
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| JP2002057583A JP3784336B2 (en) | 2002-03-04 | 2002-03-04 | Method for producing polymer particles |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007197573A (en) * | 2006-01-26 | 2007-08-09 | Sekisui Plastics Co Ltd | Light diffusion resin particle |
| WO2011048678A1 (en) * | 2009-10-21 | 2011-04-28 | ナノマイザー・プライベート・リミテッド | Refined oil production method and refined oil agitation device |
| KR101203222B1 (en) | 2012-03-20 | 2012-11-21 | 전남대학교산학협력단 | Preparation method of artificial dust |
| KR20140080484A (en) * | 2011-09-29 | 2014-06-30 | 가부시기가이샤 닛뽕쇼꾸바이 | Vinyl polymer microparticles, method for producing same, resin composition, and optical material |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07292003A (en) * | 1994-04-25 | 1995-11-07 | Sekisui Plastics Co Ltd | Production of fine polymer particle uniform in size |
| JPH0892524A (en) * | 1994-09-19 | 1996-04-09 | Nippon Shokubai Co Ltd | Aqueous composite resin dispersion and its production |
| JPH10152506A (en) * | 1996-09-24 | 1998-06-09 | Sekisui Plastics Co Ltd | Production of polymeric particle |
| JP2002055487A (en) * | 2000-08-10 | 2002-02-20 | Nippon Zeon Co Ltd | Method for manufacturing toner |
-
2002
- 2002-03-04 JP JP2002057583A patent/JP3784336B2/en not_active Expired - Lifetime
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07292003A (en) * | 1994-04-25 | 1995-11-07 | Sekisui Plastics Co Ltd | Production of fine polymer particle uniform in size |
| JPH0892524A (en) * | 1994-09-19 | 1996-04-09 | Nippon Shokubai Co Ltd | Aqueous composite resin dispersion and its production |
| JPH10152506A (en) * | 1996-09-24 | 1998-06-09 | Sekisui Plastics Co Ltd | Production of polymeric particle |
| JP2002055487A (en) * | 2000-08-10 | 2002-02-20 | Nippon Zeon Co Ltd | Method for manufacturing toner |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007197573A (en) * | 2006-01-26 | 2007-08-09 | Sekisui Plastics Co Ltd | Light diffusion resin particle |
| WO2011048678A1 (en) * | 2009-10-21 | 2011-04-28 | ナノマイザー・プライベート・リミテッド | Refined oil production method and refined oil agitation device |
| KR20140080484A (en) * | 2011-09-29 | 2014-06-30 | 가부시기가이샤 닛뽕쇼꾸바이 | Vinyl polymer microparticles, method for producing same, resin composition, and optical material |
| JPWO2013047687A1 (en) * | 2011-09-29 | 2015-03-26 | 株式会社日本触媒 | Vinyl polymer fine particles, process for producing the same, resin composition and optical material |
| KR102141982B1 (en) | 2011-09-29 | 2020-08-06 | 가부시기가이샤 닛뽕쇼꾸바이 | Vinyl polymer microparticles, method for producing same, resin composition, and optical material |
| KR101203222B1 (en) | 2012-03-20 | 2012-11-21 | 전남대학교산학협력단 | Preparation method of artificial dust |
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