JP3319114B2 - Hydrophobic silica powder, its production method and electrophotographic developer containing it - Google Patents
Hydrophobic silica powder, its production method and electrophotographic developer containing itInfo
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- JP3319114B2 JP3319114B2 JP33679093A JP33679093A JP3319114B2 JP 3319114 B2 JP3319114 B2 JP 3319114B2 JP 33679093 A JP33679093 A JP 33679093A JP 33679093 A JP33679093 A JP 33679093A JP 3319114 B2 JP3319114 B2 JP 3319114B2
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- Japan
- Prior art keywords
- silica powder
- hydrophobic
- silane compound
- amino
- toner
- Prior art date
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Description
【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION
【０００１】[0001]
【産業上の利用分野】本発明はトナー添加剤として有用
な疎水性シリカ粉体、その製造方法およびこれを含有す
る電子写真用現像剤に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrophobic silica powder useful as a toner additive, a method for producing the same, and an electrophotographic developer containing the same.
【０００２】[0002]
【従来の技術】微細なシリカ (SiO2) 粉体の表面に有機
物を付着させて疎水化処理した、いわゆる疎水性シリカ
粉体 (以下、単に疎水性シリカという) は、複写機、レ
ーザープリンタ、普通紙ファクシミリなどを含む電子写
真において、トナーの流動性改善剤として広く用いられ
ている。このような用途においては、キャリアである鉄
あるいは酸化鉄に対する摩擦帯電性が重要な性質の一つ
となっている。 2. Description of the Related Art A so-called hydrophobic silica powder (hereinafter referred to simply as "hydrophobic silica") obtained by attaching an organic substance to the surface of fine silica (SiO 2 ) powder to make it hydrophobic is used in copiers, laser printers, and the like. In electrophotography including plain paper facsimile, etc., it is widely used as a toner fluidity improver. In such applications, triboelectricity with respect to iron or iron oxide as a carrier is one of important properties.
【０００３】トナーは、静電潜像の形成に使用された感
光体の電荷に応じて、その逆極性のものを使用する。そ
のため、トナーの帯電性を阻害したり、大きく変更させ
ないように、疎水性シリカに対してもトナーと同じ極性
のものを使用し、この帯電性が安定していることが望ま
れる。感光体として従来主に使用されてきたセレンなど
のカルコゲン系材料は正極性を有するので、負に帯電し
たトナーが現像に使用され、そのため疎水性シリカとし
ても負帯電型のものが使用されてきた。これに対し、最
近開発された有機半導体からなる感光体は一般に負極性
型であるので、正に帯電したトナーが使用され、正帯電
量の大きいシリカが求められている。[0003] The toner having the opposite polarity to the charge of the photoreceptor used to form the electrostatic latent image is used. Therefore, it is desirable that hydrophobic silica having the same polarity as that of the toner be used and that the chargeability be stable so that the chargeability of the toner is not hindered or largely changed. Since chalcogen-based materials such as selenium which have been mainly used as photoreceptors in the past have a positive polarity, negatively charged toner is used for development, and therefore, negatively charged hydrophobic silica has been used as a hydrophobic silica. . On the other hand, recently developed photoconductors made of an organic semiconductor are generally of a negative polarity type. Therefore, a positively charged toner is used, and silica having a large positive charge is required.
【０００４】疎水性シリカの鉄に対する摩擦帯電量は、
その疎水化処理に用いた有機物の種類によって正あるい
は負の値を示す。正帯電性を示すシリカ粉体を得る方法
の一つとして、アミノ置換シラン化合物でシリカ粉体の
表面を処理する方法が知られている (特開昭53−22447
号) 。このアミノ置換シラン化合物で処理したシリカ粉
体は、そのままでは親水性であるため、疎水性とするた
めに疎水性シラン化合物であるヘキサメチルジシラザン
で二重処理したものが一般に用いられている。しかし、
アミノ置換シラン化合物とヘキサメチルジシラザンとで
二重処理しても、得られる疎水性シリカの疎水性はなお
不十分で、環境、特に湿気の影響を受けやすく、帯電量
が一定しない、現像剤の寿命が短いなどの問題点が指摘
されていた。またその帯電量も十分ではなかった。[0004] The amount of triboelectric charging of hydrophobic silica to iron is
It shows a positive or negative value depending on the type of the organic substance used for the hydrophobic treatment. As one method of obtaining silica powder exhibiting positive chargeability, a method of treating the surface of silica powder with an amino-substituted silane compound is known (Japanese Patent Application Laid-Open No. 53-22447).
No.) Since the silica powder treated with the amino-substituted silane compound is hydrophilic as it is, a silica powder that is double-treated with hexamethyldisilazane, which is a hydrophobic silane compound, is generally used to make the silica powder hydrophobic. But,
Even if the amino-substituted silane compound and hexamethyldisilazane are double-treated, the resulting hydrophobic silica still has insufficient hydrophobicity, is easily affected by the environment, particularly moisture, and has a variable charge amount. Problems, such as the short lifespan, were pointed out. Also, the charge amount was not sufficient.
【０００５】また、ヘキサメチルジシラザンの代わりに
ジメチルシリコーン (別名：ジメチルポリシロキサン)
を用い、アミノ置換シラン化合物との二重処理を行っ
て、十分な帯電量を保持したまま、高い疎水性をもった
疎水性シリカを得る方法も提案されている (特開平５−
97423 号) 。しかしこの方法によって得られるシリカ粉
体はヘキサメチルジシラザンを用いたシリカ粉体に比べ
て流動性が低下するという欠点を有する。Also, dimethyl silicone (also known as dimethyl polysiloxane) is used instead of hexamethyldisilazane.
A method of performing a double treatment with an amino-substituted silane compound to obtain a hydrophobic silica having high hydrophobicity while maintaining a sufficient charge amount (Japanese Patent Laid-Open No. Hei 5-
97423). However, the silica powder obtained by this method has a disadvantage that the fluidity is lower than that of silica powder using hexamethyldisilazane.
【０００６】[0006]
【発明が解決しようとする課題】本発明の目的は、十分
な疎水性と鉄に対する正の摩擦帯電性とを併せ持ち、か
つ十分なトナー流動性の改善効果を安定して示す疎水性
シリカとその製造方法を提供することにある。本発明の
別の目的は、上記のシリカ粉体をトナーに添加すること
により、安定した帯電性を持ち、流動性に優れた電子写
真用現像剤を提供することである。SUMMARY OF THE INVENTION An object of the present invention is to provide a hydrophobic silica having both sufficient hydrophobicity and a positive triboelectric charging property with respect to iron and exhibiting a sufficient toner fluidity improving effect stably. It is to provide a manufacturing method. Another object of the present invention is to provide an electrophotographic developer having stable charging properties and excellent fluidity by adding the above silica powder to a toner.
【０００７】[0007]
【発明の構成】発明者らは、上記の目的を達成すべく鋭
意研究を行った結果、少なくとも一つの置換基が炭素数
３以上のアルキル基である疎水性シラン化合物とアミノ
置換シラン化合物とを組み合わせて用いたシリカ粉体の
表面処理によって、上記目的が達成されることを見出し
た。The present inventors have conducted intensive studies to achieve the above object, and as a result, have found that a hydrophobic silane compound and an amino-substituted silane compound in which at least one substituent is an alkyl group having 3 or more carbon atoms are used. It has been found that the above object is achieved by the surface treatment of the silica powder used in combination.
【０００８】本発明の要旨は、触媒としての有機アミン
の存在下もしくはアンモニアの存在下で、一般式(1) ま
たは(2) で示される疎水性有機ケイ素化合物と、一般式
(3)で示されるアミノ置換シラン化合物とで表面処理さ
れた、透過率法で測定した疎水化率が60％以上で、鉄に
対して正の帯電性を持った疎水性シリカにある。The gist of the present invention is to provide an organic amine as a catalyst.
In the presence of or in the presence of ammonia, a hydrophobic organosilicon compound represented by the general formula (1) or (2),
Hydrophobic silica which is surface-treated with the amino-substituted silane compound represented by (3), has a hydrophobicity of 60% or more as measured by a transmittance method, and has a positive chargeability with respect to iron.
【０００９】一般式(1) ： R1 Si (R2)n (R3)3-n 一般式(2) ： R1 (R2)2 Si NH Si R1 (R2)2 一般式(3) ： (R4)x (R5)y Si (R6)z 式中、R1：炭素数３〜20のアルキル基、 R2：炭素数１〜20のアルキル基、 R3：Ｉ、Cl、Br、またはアルコキシル基、 R4：アミノ基を含有するアルキル基、 R5：炭素数１〜20のアルキル基、 R6：Ｉ、Cl、Br、またはアルコキシル基、 ｎ：０、１、または２、 ｘ：１〜３の整数、 ｙ：０、１、または２、 ｚ：１〜３の整数、 ｘ＋ｙ＋ｚ＝４。General formula (1): R 1 Si (R 2 ) n (R 3 ) 3-n General formula (2): R 1 (R 2 ) 2 Si NHSi R 1 (R 2 ) 2 General formula ( 3): (R 4 ) x (R 5 ) y Si (R 6 ) z In the formula, R 1 : an alkyl group having 3 to 20 carbon atoms, R 2 : an alkyl group having 1 to 20 carbon atoms, R 3 : I , Cl, Br or an alkoxyl group, R 4 : an alkyl group containing an amino group, R 5 : an alkyl group having 1 to 20 carbon atoms, R 6 : I, Cl, Br or an alkoxyl group, n: 0, 1 Or 2, x: an integer of 1 to 3, y: 0, 1, or 2, z: an integer of 1 to 3, x + y + z = 4.
【００１０】本発明によれば、触媒としての有機アミン
の存在下もしくはアンモニアの存在下で、浮遊状態にあ
るシリカ粉体を上記一般式(1) または(2) で示される疎
水性有機ケイ素化合物および上記一般式(3) で示される
アミノ置換シラン化合物と接触させることからなる疎水
性シリカの製造方法、およびこの疎水性シリカを含有す
ることを特徴とする静電写真用現像剤も提供される。According to the present invention, an organic amine as a catalyst
In the presence of or in the presence of ammonia , the silica powder in a suspended state is converted into a hydrophobic organosilicon compound represented by the general formula (1) or (2) and an amino-substituted silane compound represented by the general formula (3). And a method for producing hydrophobic silica, which comprises contacting the hydrophobic silica, and a developer for electrostatography comprising the hydrophobic silica.
【００１１】本発明で用いる前記一般式(1) および(2)
で示される疎水性有機ケイ素化合物は、いずれも炭素数
３以上の長鎖アルキル基（R1基）を少なくとも１つ有す
ることを共通の特徴とする、それぞれシランおよびジシ
ラザン化合物であり、この長鎖アルキル基の存在により
化合物が疎水性を示す。以下、この一般式(1) および
(2) で示される化合物を、疎水性シラン化合物と総称す
る。この長鎖アルキル基を有する疎水性シラン化合物を
用いてシリカ粉体を表面処理すると、この化合物が粉体
表面と反応して、シリカ粉体に十分な疎水性と流動性と
が付与される。この長鎖アルキル基の炭素数は３以上、
20以下であればよいが、さらに高い疎水性と流動性を付
与するには６〜12の範囲内が望ましい。R2基は好ましく
は炭素数１〜３のアルキル基である。一般式(1) または
(2) で示される化合物の代表例として次の化合物が例示
されるが、これら以外のものも使用可能である（Me＝CH
3 、Et＝C2H5) 。The general formulas (1) and (2) used in the present invention
Are silane and disilazane compounds, each having at least one long-chain alkyl group (R 1 group) having 3 or more carbon atoms. The compound exhibits hydrophobicity due to the presence of the alkyl group. Hereinafter, this general formula (1) and
The compound represented by (2) is generically referred to as a hydrophobic silane compound. When the silica powder is subjected to surface treatment using the hydrophobic silane compound having a long-chain alkyl group, the compound reacts with the powder surface to impart sufficient hydrophobicity and fluidity to the silica powder. This long-chain alkyl group has 3 or more carbon atoms,
It may be 20 or less, but is preferably in the range of 6 to 12 to impart higher hydrophobicity and fluidity. The R 2 group is preferably an alkyl group having 1 to 3 carbon atoms. General formula (1) or
The following compounds are exemplified as typical examples of the compound represented by (2), but other compounds can also be used (Me = CH
3, Et = C 2 H 5 ).
【００１２】C3H7Si(OMe)3、 C6H13Si(OEt)3 、C6
H13SiCl3、 C8H17SiMe(OMe)2 、C8H17SiMeCl2、
C10H21Si(OMe)3、C12H25Si(OEt)3、 C4H9SiMe
2NHSiMe2C4H9。C 3 H 7 Si (OMe) 3 , C 6 H 13 Si (OEt) 3 , C 6
H 13 SiCl 3, C 8 H 17 SiMe (OMe) 2, C 8 H 17 SiMeCl 2,
C 10 H 21 Si (OMe) 3 , C 12 H 25 Si (OEt) 3 , C 4 H 9 SiMe
2 NHSiMe 2 C 4 H 9 .
【００１３】本発明で用いる一般式(3) で示されるアミ
ノ置換シラン化合物は、シリカ粉体の表面と反応するこ
とにより、シリカ粉体に鉄に対する正の帯電性を付与す
る。一般式(3) において、R4基に含まれるアミノ基は第
一、第二、第三アミノ基のいずれでもよく、アミノ置換
基の数は１または２以上でよい。R4基の炭素数は特に制
限されないが、通常は１〜20の範囲内である。好ましい
R4基は、アミノアルキル基、アミノアルキルアミノアル
キル基、フェニルアミノアルキル基などである。R5基は
好ましくは炭素数１〜３のアルキル基である。アミノ置
換シラン化合物の代表例としては次の化合物が例示され
るが、これら以外のものも使用可能である。The amino-substituted silane compound represented by the general formula (3) used in the present invention gives the silica powder a positive chargeability to iron by reacting with the surface of the silica powder. In the general formula (3), the amino group contained in the R 4 group may be any of primary, secondary and tertiary amino groups, and the number of amino substituents may be one or two or more. The number of carbon atoms of the R 4 group is not particularly limited, but is usually in the range of 1 to 20. preferable
The R 4 group is an aminoalkyl group, an aminoalkylaminoalkyl group, a phenylaminoalkyl group, or the like. The R 5 group is preferably an alkyl group having 1 to 3 carbon atoms. The following compounds are exemplified as typical examples of the amino-substituted silane compound, but other compounds can also be used.
【００１４】H2N(CH2)3Si(OEt)3 、H2N(CH2)2NH(CH2)3S
i(OMe)3 、H2N(CH2)2NH(CH2)3SiMe(OMe)3 、C6H5HN(C
H2)3Si(OMe)3、H2N(CH2)2NH(CH2)3SiCl3。H 2 N (CH 2 ) 3 Si (OEt) 3 , H 2 N (CH 2 ) 2 NH (CH 2 ) 3 S
i (OMe) 3 , H 2 N (CH 2 ) 2 NH (CH 2 ) 3 SiMe (OMe) 3 , C 6 H 5 HN (C
H 2) 3 Si (OMe) 3, H 2 N (CH 2) 2 NH (CH 2) 3 SiCl 3.
【００１５】本発明で用いるシリカ粉体は、コロイダル
シリカと呼ばれる微細粒子からなるシリカである。シリ
カ粉体の粒径は、その帯電特性が要求される用途に適し
たものであればよく、特に制限されないが、通常は比表
面積が50 m2/g 以上のものが好ましい。好適なシリカ粉
体の平均一次粒径は、一般に数nmから数百nm程度であ
る。The silica powder used in the present invention is silica composed of fine particles called colloidal silica. The particle size of the silica powder is not particularly limited as long as it is suitable for applications requiring its charging characteristics, and is usually preferably 50 m 2 / g or more in specific surface area. The average primary particle size of a suitable silica powder is generally about several nm to several hundred nm.
【００１６】鉄に対する摩擦帯電量の測定方法は、文献
(例、色材, 55[9] 630-636, 1982)に記載の方法に準じ
て行えばよい。この摩擦帯電量はアミノ置換シラン化合
物の使用量に依存して変化するので、その使用量を調整
することにより所望の帯電量を得ることができる。正帯
電型のトナーに使用する場合、一般には、鉄に対する摩
擦帯電量が＋20μC/ｇから＋700 μC/ｇの範囲、特に＋
100 μC/ｇから＋300μC/ｇの範囲にあることが望まし
い。A method for measuring the triboelectric charge amount on iron is described in the literature.
(Eg, coloring materials, 55 [9] 630-636, 1982). Since the triboelectric charge varies depending on the amount of the amino-substituted silane compound used, a desired amount of charge can be obtained by adjusting the amount of the trisubstituted silane compound. When used for a positively charged toner, the triboelectric charge amount to iron is generally in the range of +20 μC / g to +700 μC / g,
It is desirable to be in the range of 100 μC / g to +300 μC / g.
【００１７】本発明では、疎水性シリカの疎水化率を透
過率法により実験的に求める。透過率法による疎水化率
の測定は以下の手順によって行われる。測定する疎水性
シリカの粉体試料1.0 ｇを水100 mLと共に抽出用フラス
コに入れ、５分間はげしく振盪攪拌する。その後１分間
静置し、フラスコの底から少量の懸濁液を抜き出す。こ
の液の550 nmの光に対する透過率を、純水の透過率を10
0 ％として表した値を、そのシリカの疎水化率とする。In the present invention, the hydrophobicity of the hydrophobic silica is experimentally determined by a transmittance method. The measurement of the hydrophobicity by the transmittance method is performed by the following procedure. 1.0 g of a hydrophobic silica powder sample to be measured is put into an extraction flask together with 100 mL of water, and vigorously shaken and stirred for 5 minutes. After that, it is left still for 1 minute, and a small amount of the suspension is withdrawn from the bottom of the flask. The transmittance of this solution for light at 550 nm is 10%.
The value expressed as 0% is defined as the hydrophobicity of the silica.
【００１８】このようにして測定された疎水化率の値が
高いほど、そのシリカ粉体は吸湿性が低く、トナーに添
加した場合に湿度に対するトナーの帯電量の変化を小さ
くし、かつ凝集を防ぐ効果が高まるので、利用価値が高
い。実用上は、こうして求めた疎水化率が60％以上であ
れば、トナーの流動性改善効果が十分であるので、本発
明においては疎水性シリカの疎水化率を60％以上とす
る。望ましくは、疎水化率が70％以上であると、さらに
良好な結果が得られる。The higher the value of the hydrophobization ratio thus measured, the lower the hygroscopicity of the silica powder, the smaller the change in the charge amount of the toner with respect to humidity when added to the toner, and the less the aggregation. As the effect of prevention increases, the utility value is high. In practical use, if the hydrophobicity ratio thus obtained is 60% or more, the effect of improving the fluidity of the toner is sufficient, so that the hydrophobicity ratio of the hydrophobic silica is set to 60% or more in the present invention. Desirably, a better result is obtained when the hydrophobicity ratio is 70% or more.
【００１９】本発明の疎水性シリカ粉体は、適当な粒径
(または比表面積) のシリカ粉体を、上記一般式(1) ま
たは(2) で示される少なくとも１種の疎水性シラン化合
物と上記一般式(3) で示される少なくとも１種のアミノ
置換シラン化合物とで表面処理することにより製造され
る。この表面処理は従来より公知の種々の方法で実施す
ることができるが、シリカ粉体を浮遊状態にして、上記
の２種類のシラン化合物をこの粉体と接触させる処理方
法が、凝集がなく均一に処理された疎水性シリカが得ら
れることから好ましい方法である。The hydrophobic silica powder of the present invention has an appropriate particle size.
(Or specific surface area) of the silica powder is obtained by mixing at least one hydrophobic silane compound represented by the above general formula (1) or (2) and at least one amino-substituted silane compound represented by the above general formula (3) It is manufactured by surface treatment with This surface treatment can be carried out by various conventionally known methods. However, the treatment method in which the silica powder is brought into a suspended state and the above-mentioned two kinds of silane compounds are brought into contact with the powder is performed without aggregation. This is a preferred method, since a hydrophobic silica treated with the above method can be obtained.
【００２０】シリカ粉体は非常に微細な粒子であるの
で、機械的な攪拌のみで浮遊状態とすることができる。
従って、被処理シリカ粉体を機械的に十分攪拌して浮遊
状態とし、この状態で疎水性シラン化合物とアミノ置換
シラン化合物とを、必要であれば溶剤に溶解するか、溶
剤で希釈して、同時にあるいは順次 (いずれが先でもよ
い) 、滴下あるいは噴霧して加えることにより処理を行
うことができる。この処理によりシリカ粉体の表面は、
疎水性シラン化合物およびアミノ置換シラン化合物と反
応 (シリカ表面の水酸基とこれらのシラン化合物中のア
ルコキシル基もしくはハロゲン基およびアミノ基とが反
応) する。同時に、粉体の表面に結合した疎水性シラン
化合物およびアミノ置換シラン化合物は、これらに含ま
れるアルコキシル基またはハロゲンが周囲の微量の水分
と反応して加水分解を受けることによって、シロキサン
(Si−Ｏ) 結合により架橋して被膜を形成することがで
きるため、シリカ粉体の表面は、表面に強固に結合した
これらのシラン化合物から形成された被膜で部分的また
は完全に被覆されることになる。それにより、これらの
各シラン化合物にそれぞれ固有の表面特性がシリカ粉体
の表面に付与され、鉄に対して十分な正の帯電量を示す
と同時に、表面が疎水化されたシリカ粉体、即ち、疎水
性シリカが得られる。そして、被膜がシリカ粉体の表面
と強固に結合していることにより、疎水性や帯電性が高
温多湿といった苛酷な環境下でも安定して持続する。Since the silica powder is very fine particles, it can be brought into a floating state only by mechanical stirring.
Therefore, the silica powder to be treated is mechanically sufficiently stirred to be in a floating state, and in this state, the hydrophobic silane compound and the amino-substituted silane compound are dissolved or diluted with a solvent if necessary. The treatment can be carried out by dropping or spraying simultaneously or sequentially (whichever may be the first). By this treatment, the surface of the silica powder becomes
Reacts with a hydrophobic silane compound and an amino-substituted silane compound (a hydroxyl group on the silica surface reacts with an alkoxyl group or a halogen group and an amino group in these silane compounds). At the same time, the hydrophobic silane compound and the amino-substituted silane compound bonded to the surface of the powder are hydrolyzed by the alkoxyl group or halogen contained therein reacting with a small amount of surrounding water to undergo hydrolysis.
The surface of the silica powder is partially or completely covered with a film formed from these silane compounds firmly bonded to the surface because the film can be formed by crosslinking by (Si-O) bonds. Will be. Thereby, each of these silane compounds is given a unique surface property to the surface of the silica powder, and shows a sufficient positive charge amount with respect to iron, and at the same time, a silica powder whose surface is hydrophobized, that is, , A hydrophobic silica is obtained. And, since the film is firmly bonded to the surface of the silica powder, the hydrophobicity and the chargeability are stably maintained even in a severe environment such as high temperature and high humidity.
【００２１】滴下または噴霧に適した粘度の液状の処理
液とするために、用いる疎水性シラン化合物およびアミ
ノ置換シラン化合物の性状に応じて、アルコール、ケト
ンまたは炭化水素等の適当な有機溶剤を溶媒または希釈
剤として用いることができる。また、得られた処理液に
は、シリカ粉体表面と疎水性シラン化合物およびアミノ
置換シラン化合物との反応性を高める触媒として、ジエ
チルアミンなどの有機アミン類を加えるか、あるいはア
ミンの添加の代わりに、アンモニアガスを被処理シリカ
粉体中に吹き込むことも可能である。処理液添加後、10
0 ℃から250 ℃の範囲の温度で加熱して反応を完結させ
ると共に、溶剤を除去することが好ましい。この場合の
加熱時間は温度にもよるが、通常は昇温時間を含めて１
〜５時間である。以上の処理は、処理剤である上記２種
類のシラン化合物の酸化を防止するために、窒素などの
不活性ガス雰囲気中で行うことが好ましい。In order to obtain a liquid treatment liquid having a viscosity suitable for dropping or spraying, an appropriate organic solvent such as alcohol, ketone or hydrocarbon is used depending on the properties of the hydrophobic silane compound and the amino-substituted silane compound to be used. Alternatively, it can be used as a diluent. In addition, an organic amine such as diethylamine is added to the obtained treatment solution as a catalyst for increasing the reactivity between the silica powder surface and the hydrophobic silane compound and the amino-substituted silane compound, or instead of adding the amine, It is also possible to blow ammonia gas into the silica powder to be treated. After adding the processing solution, 10
It is preferred to heat at a temperature in the range of 0 ° C. to 250 ° C. to complete the reaction and to remove the solvent. In this case, the heating time depends on the temperature.
~ 5 hours. The above treatment is preferably performed in an atmosphere of an inert gas such as nitrogen in order to prevent oxidation of the above two types of silane compounds as treatment agents.
【００２２】上記の処理によって本発明の疎水性シリカ
(即ち、透過率法により測定された疎水化率が60％以上
であり、かつ正の帯電性を持ったシリカ粉体) を得るの
に必要な上記２種類の処理剤の使用量は、求める正帯電
量および被処理シリカ粉体の比表面積や処理剤の種類な
どの条件に依存して変動する。必要な処理剤の使用量
は、実験により容易に求めることができる。比表面積13
0 m2/gのシリカ粉体を処理する場合を例にとると、シリ
カ粉体の重量に対して、疎水性シラン化合物の使用量が
2.0〜15.0重量％、好ましくは 4.0〜10.0重量％程度、
アミノ置換シラン化合物の使用量が 1.0〜15.0重量％、
好ましくは2.0 〜10.0重量％程度の範囲内で透過率法に
より測定された疎水化率が60％以上であり、かつ正の帯
電性を持ったシリカ粉体を得ることができる。By the above treatment, the hydrophobic silica of the present invention is obtained.
(That is, a silica powder having a hydrophobicity of 60% or more as measured by the transmittance method and having a positive chargeability), the amounts of the above two types of processing agents required to obtain the powder are determined. It varies depending on conditions such as the amount of positive charge, the specific surface area of the silica powder to be treated, and the type of treatment agent. The necessary amount of the treatment agent can be easily determined by an experiment. Specific surface area 13
Taking silica powder of 0 m 2 / g as an example, the amount of hydrophobic silane compound used is
2.0 to 15.0% by weight, preferably about 4.0 to 10.0% by weight,
The amount of the amino-substituted silane compound is 1.0 to 15.0% by weight,
Preferably, within a range of about 2.0 to 10.0% by weight, a silica powder having a hydrophobicity of at least 60% as measured by a transmittance method and having a positive chargeability can be obtained.
【００２３】２種類の処理剤の使用割合も、処理により
上記特性の疎水性シリカが得られる限り、特に制限され
ないが、通常はアミノ置換シラン化合物：疎水性シラン
化合物の重量比で10：３〜３：10の範囲であろう。The proportion of the two types of treating agents is not particularly limited as long as the hydrophobic silica having the above properties can be obtained by the treatment. However, usually, the weight ratio of the amino-substituted silane compound to the hydrophobic silane compound is from 10: 3 to 10: 3. It will be in the range of 3:10.
【００２４】上記のように疎水性シラン化合物とアミノ
置換シラン化合物とで処理された本発明の疎水性シリカ
粉体は、通常の方法でトナーに添加できる。トナーは一
般に熱可塑性樹脂の他に少量の顔料および電荷制御剤を
含有する。このトナーをキャリア (通常は鉄粉または酸
化鉄粉) およびその他の添加剤と混合すると、本発明の
電子写真用現像剤が得られる。この現像剤は、トナーに
本発明の疎水性シリカが配合されていれば、他の成分は
従来と同様でよく、また一成分系と二成分系のいずれで
もよい。The hydrophobic silica powder of the present invention treated with the hydrophobic silane compound and the amino-substituted silane compound as described above can be added to a toner by a usual method. Toners generally contain small amounts of pigments and charge control agents in addition to the thermoplastic resin. When this toner is mixed with a carrier (usually iron powder or iron oxide powder) and other additives, the electrophotographic developer of the present invention is obtained. As long as the toner contains the hydrophobic silica of the present invention, the other components of this developer may be the same as those of the related art, and may be either a one-component system or a two-component system.
【００２５】本発明の疎水性シリカ粉体は、トナー中に
比較的多量に含有させてもトナーの特性を損なうことが
なく、トナーの流動性を十分に高めることができる。ま
た、得られた現像剤が湿度や温度の影響を受けにくくな
り、カブリや画像の低下も起こしにくくなることも確認
された。The hydrophobic silica powder of the present invention can sufficiently increase the fluidity of the toner without impairing the properties of the toner even if it is contained in the toner in a relatively large amount. In addition, it was also confirmed that the obtained developer was hardly affected by humidity and temperature, and fog and image deterioration were hardly caused.
【００２６】本発明の疎水性シリカのトナーへの添加量
は、得られる現像剤が上記の特性向上を示すような量で
あればよく、特に制限されないが、通常はトナーの全重
量に基づいて0.05〜5.0 重量％、好ましくは 0.1〜10重
量％程度である。The amount of the hydrophobic silica of the present invention to be added to the toner is not particularly limited as long as the obtained developer exhibits the above-mentioned property improvement, and is not particularly limited, but is usually based on the total weight of the toner. It is about 0.05 to 5.0% by weight, preferably about 0.1 to 10% by weight.
【００２７】[0027]
【実施例】本発明に対する理解を助ける目的で以下に実
施例および比較例を示すが、これらは本発明をなんら限
定するものではない。実施例において、透過率法による
疎水化率の測定は上記手順により行い、鉄に対する摩擦
帯電量の測定は、色材, 55[9] 630-636, 1982 に記載の
方法に準じて行った。EXAMPLES Examples and comparative examples are shown below for the purpose of assisting the understanding of the present invention, but they do not limit the present invention in any way. In the examples, the measurement of the hydrophobization rate by the transmittance method was performed according to the above procedure, and the measurement of the triboelectric charge amount with respect to iron was performed according to the method described in Coloring Materials, 55 [9] 630-636, 1982.
【００２８】(実施例１)加熱乾燥させたシリカ粉体 (比
表面積130 m2/g) 20ｇをステンレス製の容器に仕込み、
窒素雰囲気下でシリカ粉体が浮遊するように機械的に攪
拌しながら、下記組成の処理剤Ａ、Ｂを室温で順に噴霧
して、シリカ粉体の処理を行った。Example 1 20 g of heat-dried silica powder (specific surface area: 130 m 2 / g) was charged into a stainless steel container,
Under a nitrogen atmosphere, treating agents A and B having the following composition were sprayed in order at room temperature while mechanically stirring the silica powder so that the silica powder floated, thereby treating the silica powder.
【００２９】処理剤組成 Ａ：疎水性シラン化合物 [C6H13Si(OMe)3] 1.0 ｇ ジエチルアミン 数滴 メタノール 4.0 mL Ｂ：アミノ置換シラン化合物 [H2N(CH2)3Si(OEt)3] 0.5 ｇ ジエチルアミン 数滴 ｉ−プロパノール 4.0 mL 噴霧終了後、シリカ粉体の攪拌を続けながら、窒素気流
下で外部加熱を行った。50分かけて220 ℃まで昇温さ
せ、この温度で４時間保持したのち、室温まで放冷し
た。得られた疎水性シリカの透過率法による疎水化率お
よび鉄に対する摩擦帯電量は、それぞれ85％と＋63μC/
ｇであった。 Treatment agent composition A: Hydrophobic silane compound [C 6 H 13 Si (OMe) 3 ] 1.0 g A few drops of diethylamine Methanol 4.0 mL B: Amino-substituted silane compound [H 2 N (CH 2 ) 3 Si (OEt) 3 ] 0.5 g A few drops of diethylamine 4.0 mL of i-propanol After the completion of spraying, external heating was performed under a nitrogen stream while stirring the silica powder. The temperature was raised to 220 ° C. over 50 minutes, kept at this temperature for 4 hours, and allowed to cool to room temperature. The hydrophobicity of the obtained hydrophobic silica by the transmittance method and the triboelectric charge against iron were 85% and +63 μC /
g.
【００３０】次に、スチレン−アクリル酸共重合樹脂中
に、この樹脂量に対して18重量％のカーボン (顔料) お
よび３重量％のニグロシン (電荷制御剤) を分散させ、
粉砕後、５〜10μｍ (平均粒径７μｍ) と 7.5〜20μｍ
(平均粒径10μｍ) とに分級して、粒度の異なる２種類
の着色樹脂粉末からなるトナーを用意した (これらを、
以下ではそれぞれ７μｍのトナーおよび10μｍのトナー
という) 。この２種類のトナー各 100ｇ中に、上記疎水
性シリカを７μｍのトナーには 0.3ｇ、10μｍのトナー
には 0.5ｇを混合し、この疎水性シリカを添加したトナ
ーを用いて流動性試験を行った。Next, 18% by weight of carbon (pigment) and 3% by weight of nigrosine (charge controlling agent) are dispersed in the styrene-acrylic acid copolymer resin based on the amount of the resin.
After grinding, 5-10μm (average particle size 7μm) and 7.5-20μm
(Average particle size of 10 μm) to prepare a toner composed of two kinds of colored resin powders having different particle sizes.
Hereinafter, they are referred to as 7 μm toner and 10 μm toner, respectively). To 100 g of each of the two types of toner, 0.3 g of the above-mentioned hydrophobic silica was mixed with a 7 μm toner and 0.5 g of a 10 μm toner, and a fluidity test was performed using the toner to which the hydrophobic silica was added. Was.
【００３１】流動性試験は、試験するトナーの試料10ｇ
を48メッシュ (上) と100 メッシュ(下) の２つの篩を
重ねた上に置き、電磁式実験用篩振盪機 (フリッチュ
社) を用いて、強度３で１分間の篩分けを行い、100 メ
ッシュの篩を通過したトナーの割合で評価した。この場
合、７μｍのトナーでは77％、10μｍのトナーでは69％
という流動性の結果が得られた。In the fluidity test, a 10 g sample of the toner to be tested was used.
Was placed on top of two sieves of 48 mesh (top) and 100 mesh (bottom), and sieved for 1 minute at a strength of 3 using an electromagnetic laboratory sieve shaker (Fritsch). The evaluation was made based on the percentage of the toner that passed through the mesh sieve. In this case, 77% for 7 μm toner and 69% for 10 μm toner
Was obtained.
【００３２】さらに、この疎水性シリカを含有する２種
類のトナー30ｇをそれぞれ酸化鉄粉1000ｇと混合して、
電子写真用現像剤を調製した。この現像剤の摩擦帯電量
は、どちらのトナーの場合も＋15μC/ｇであった。Further, 30 g of the two kinds of toners containing the hydrophobic silica were mixed with 1000 g of iron oxide powder, respectively.
An electrophotographic developer was prepared. The triboelectric charge of this developer was +15 μC / g for both toners.
【００３３】本現像剤を市販の複写機に入れ、寿命テス
トを行ったところ、約25,000枚以上のコピーにおいても
画像にカブリを生じなかった。さらに高温多湿 (28℃、
85％RH) の環境下においても同じテストを行ったとこ
ろ、同様にカブリがなく、コントラストの高い良好な画
像がほぼ同じ枚数まで得られた。The developer was placed in a commercially available copying machine and subjected to a life test. As a result, no fog occurred on the image even with about 25,000 or more copies. More hot and humid (28 ℃,
(85% RH), the same test was conducted. As a result, a good image having no fog and high contrast was obtained up to almost the same number of images.
【００３４】(実施例２)加熱乾燥させたシリカ粉体 (比
表面積130 m2/g) 20ｇに、実施例１と同様に下記組成の
処理剤を室温で噴霧した。Example 2 A treatment agent having the following composition was sprayed at room temperature on 20 g of silica powder (specific surface area: 130 m 2 / g) dried by heating in the same manner as in Example 1.
【００３５】処理剤組成 疎水性シラン化合物 [C6H13Si(OMe)3] 1.0 ｇ アミノ置換シラン化合物 [H2N(CH2)3Si(OEt)3] 1.5 ｇ ジエチルアミン 数滴 ｉ−プロパノール 8.0 mL 滴下終了後、実施例１と同様に外部加熱を行った。処理
後の疎水化率および鉄に対する摩擦帯電量は、それぞれ
69％と＋277 μC/ｇであった。The treatment agent sets forming a hydrophobic silane compound [C 6 H 13 Si (OMe ) 3] 1.0 g amino-substituted silane compound [H 2 N (CH 2) 3 Si (OEt) 3] 1.5 g of diethylamine few drops i- After the addition of 8.0 mL of propanol, external heating was performed in the same manner as in Example 1. Hydrophobicity after treatment and triboelectric charge against iron
It was 69% and +277 μC / g.
【００３６】次に、この処理で得た疎水性シリカを用い
て実施例１と同様に粒度の異なる２種類のトナーを調製
し、流動性試験を行ったところ、７μｍのトナーでは55
％、10μｍのトナーでは71％であった。さらに、これら
のトナー30ｇをそれぞれ酸化鉄粉1000ｇと混合して電子
写真用現像剤とした。この現像剤の摩擦帯電量はどちら
も＋17μC/ｇであった。本現像剤を市販の複写機に入
れ、寿命テストを行ったところ、約22,000枚以上のコピ
ーにおいても画像にカブリを生じなかった。さらに高温
多湿 (28℃、85％RH) の環境下においても同じテストを
行ったところ、同様に良好な画像がほぼ同じ枚数まで得
られた。Next, two kinds of toners having different particle sizes were prepared using the hydrophobic silica obtained by this treatment in the same manner as in Example 1, and a fluidity test was carried out.
%, And 71% for the 10 μm toner. Further, 30 g of each of the toners was mixed with 1000 g of iron oxide powder to prepare an electrophotographic developer. The triboelectric charge of each developer was +17 μC / g. The developer was placed in a commercially available copying machine and subjected to a life test. As a result, no fog occurred on the image even with about 22,000 or more copies. Further, the same test was conducted in a high-temperature and high-humidity environment (28 ° C., 85% RH).
【００３７】(実施例３)加熱乾燥させたシリカ粉体 (比
表面積130 m2/g) 20ｇに、実施例１と同様に下記組成の
処理剤Ａ、Ｂを順に室温で噴霧した。Example 3 Treatment agents A and B having the following composition were sprayed at room temperature in the same manner as in Example 1 onto 20 g of the dried silica powder (specific surface area: 130 m 2 / g).
【００３８】処理剤組成 Ａ：疎水性シラン化合物 [C10H21Si(OMe)3] 1.0 ｇ ジエチルアミン 数滴 メタノール 4.0 mL Ｂ：アミノ置換シラン化合物 [H2N(CH2)3Si(OEt)3] 0.5 ｇ ジエチルアミン 数滴 ｉ−プロパノール 8.0 mL 滴下終了後、実施例１と同様に外部加熱を行った。処理
後の疎水化率および鉄に対する摩擦帯電量は、それぞれ
84％と＋101 μC/ｇであった。The treatment agent of sets formed A: hydrophobic silane compound [C 10 H 21 Si (OMe ) 3] 1.0 g of diethylamine few drops of methanol 4.0 mL B: Amino-substituted silane compound [H 2 N (CH 2) 3 Si (OEt 3 ) 0.5 g Several drops of diethylamine 8.0 mL of i-propanol After completion of the dropwise addition, external heating was performed in the same manner as in Example 1. Hydrophobicity after treatment and triboelectric charge against iron
It was 84% and +101 μC / g.
【００３９】次に、得られた疎水性シリカを用いて実施
例１と同様に粒度の異なる２種類のトナーを調製し、流
動性試験を行ったところ、７μｍのトナーでは75％、10
μｍのトナーでは67％であった。さらに、これらのトナ
ー30ｇをそれぞれ酸化鉄粉1000ｇと混合して電子写真用
現像剤とした。この現像剤の摩擦帯電量はどちらも＋16
μC/ｇであった。本現像剤を市販の複写機に入れ、寿命
テストを行ったところ、約24,000枚以上のコピーにおい
ても画像にカブリを生じなかった。さらに高温多湿 (28
℃、85％RH) の環境下においてもおいても同じテストを
行ったところ、同様に良好な画像がほぼ同じ枚数まで得
られた。Next, two kinds of toners having different particle sizes were prepared by using the obtained hydrophobic silica in the same manner as in Example 1, and a fluidity test was carried out.
It was 67% with the μm toner. Further, 30 g of each of the toners was mixed with 1000 g of iron oxide powder to prepare an electrophotographic developer. Both triboelectric charges of this developer are +16
μC / g. When this developer was placed in a commercially available copying machine and subjected to a life test, no fog occurred on the image even with about 24,000 copies or more. More hot and humid (28
(85 ° C., 85% RH), the same test was carried out, and similarly good images were obtained up to almost the same number of images.
【００４０】(実施例４)加熱乾燥させたシリカ粉体 (比
表面積200 m2/g) 20ｇに、実施例１と同様に下記組成の
処理剤Ａ、Ｂを順に室温で噴霧した。Example 4 Treatment agents A and B having the following composition were sprayed at room temperature in the same manner as in Example 1 on 20 g of heat-dried silica powder (specific surface area: 200 m 2 / g).
【００４１】処理剤組成 Ａ：疎水性シラン化合物 [C6H13SiMe(OMe)2] 2.0 ｇ ジエチルアミン 数滴 メタノール 4.0 mL Ｂ：アミノ置換シラン化合物 [H2N(CH2)2NH(CH2)3Si(OMe)3] 1.0 ｇ ジエチルアミン 数滴 アセトン 4.0 mL 滴下終了後、実施例１と同様に外部加熱を行った。処理
後の疎水化率および鉄に対する摩擦帯電量は、それぞれ
89％と＋335 μC/ｇであった。The treatment agent of sets formed A: hydrophobic silane compound [C 6 H 13 SiMe (OMe ) 2] 2.0 g of diethylamine few drops of methanol 4.0 mL B: Amino-substituted silane compound [H 2 N (CH 2) 2 NH (CH 2 ) 3 Si (OMe) 3 ] 1.0 g A few drops of diethylamine 4.0 mL of acetone After the completion of the dropping, external heating was performed in the same manner as in Example 1. Hydrophobicity after treatment and triboelectric charge against iron
89% and +335 μC / g.
【００４２】次に、この処理で得た疎水性シリカを用い
て実施例１と同様に粒度の異なる２種類のトナーを調製
し、流動性試験を行ったところ、７μｍのトナーでは51
％、10μｍのトナーでは67％であった。さらに、これら
のトナー30ｇをそれぞれ酸化鉄粉1000ｇと混合して電子
写真用現像剤とした。この現像剤の摩擦帯電量はどちら
も＋17μC/ｇであった。本現像剤を市販の複写機に入
れ、寿命テストを行ったところ、約22,000枚以上のコピ
ーにおいても画像にカブリを生じなかった。さらに高温
多湿 (28℃、85％RH) の環境下においてもおいても同じ
テストを行ったところ、同様に良好な画像がほぼ同じ枚
数まで得られた。Next, two kinds of toners having different particle sizes were prepared using the hydrophobic silica obtained by this treatment in the same manner as in Example 1, and a fluidity test was carried out.
%, And 67% with a 10 μm toner. Further, 30 g of each of the toners was mixed with 1000 g of iron oxide powder to prepare an electrophotographic developer. The triboelectric charge of each developer was +17 μC / g. The developer was placed in a commercially available copying machine and subjected to a life test. As a result, no fog occurred on the image even with about 22,000 or more copies. Further, the same test was carried out in a high-temperature and high-humidity environment (28 ° C., 85% RH).
【００４３】(実施例５)加熱乾燥させたシリカ粉体 (比
表面積130 m2/g) 20ｇに、実施例１と同様に下記組成の
処理剤Ａ、Ｂを順に室温で噴霧した。(Example 5) Treatment agents A and B having the following composition were sprayed at room temperature in the same manner as in Example 1 on 20 g of heat-dried silica powder (specific surface area: 130 m 2 / g).
【００４４】処理剤組成 Ａ：疎水性シラン化合物 [C12H25Si(OEt)3] 1.0 ｇ ジエチルアミン 数滴 エタノール 4.0 mL Ｂ：アミノ置換シラン化合物 [H2N(CH2)3Si(OEt)3] 1.0 ｇ ジエチルアミン 数滴 ｉ−プロパノール 4.0 mL 滴下終了後、実施例１と同様に外部加熱を行った。処理
後の疎水化率および鉄に対する摩擦帯電量は、それぞれ
92％と＋132 μC/ｇであった。The treatment agent of sets formed A: hydrophobic silane compound [C 12 H 25 Si (OEt ) 3] 1.0 g of diethylamine few drops of ethanol 4.0 mL B: Amino-substituted silane compound [H 2 N (CH 2) 3 Si (OEt 3 ) 1.0 g Several drops of diethylamine 4.0 mL of i-propanol After completion of the dropwise addition, external heating was performed in the same manner as in Example 1. Hydrophobicity after treatment and triboelectric charge against iron
92% and +132 μC / g.
【００４５】次に、この処理で得た疎水性シリカを用い
て実施例１と同様に粒度の異なる２種類のトナーを調製
し、流動性試験を行ったところ、７μｍのトナーでは76
％、10μｍのトナーでは68％であった。さらに、これら
のトナー30ｇをそれぞれ酸化鉄粉1000ｇと混合して電子
写真用現像剤とした。この現像剤の摩擦帯電量はどちら
も＋16μC/ｇであった。本現像剤を市販の複写機に入
れ、寿命テストを行ったところ、約26,000枚以上のコピ
ーにおいても画像にカブリを生じなかった。さらに高温
多湿 (28℃、85％RH) の環境下においてもおいても同じ
テストを行ったところ、同様に良好な画像がほぼ同じ枚
数まで得られた。Next, two types of toners having different particle sizes were prepared in the same manner as in Example 1 using the hydrophobic silica obtained by this treatment, and a fluidity test was carried out.
%, And 68% with a 10 μm toner. Further, 30 g of each of the toners was mixed with 1000 g of iron oxide powder to prepare an electrophotographic developer. The triboelectric charge of each developer was +16 μC / g. The developer was placed in a commercially available copying machine and subjected to a life test. As a result, no fog occurred on the image even with about 26,000 or more copies. Further, the same test was carried out in a high-temperature and high-humidity environment (28 ° C., 85% RH).
【００４６】(実施例６)加熱乾燥させたシリカ粉体 (比
表面積130 m2/g) 20ｇに、実施例１と同様に下記組成の
処理剤Ａ、Ｂを順に室温で噴霧した。Example 6 Treatment agents A and B having the following composition were sprayed at room temperature in the same manner as in Example 1 on 20 g of the heat-dried silica powder (specific surface area 130 m 2 / g).
【００４７】処理剤組成 Ａ：疎水性シラン化合物 [C3H7Si(OEt)3] 1.0 ｇ ジエチルアミン 数滴 エタノール 4.0 mL Ｂ：アミノ置換シラン化合物 [H2N(CH2)3Si(OEt)3] 1.0 ｇ ジエチルアミン 数滴 ｉ−プロパノール 4.0 mL 滴下終了後、実施例１と同様に外部加熱を行った。処理
後の疎水化率および鉄に対する摩擦帯電量は、それぞれ
75％と＋248 μC/ｇであった。The treatment agent of sets formed A: hydrophobic silane compound [C 3 H 7 Si (OEt ) 3] 1.0 g of diethylamine few drops of ethanol 4.0 mL B: Amino-substituted silane compound [H 2 N (CH 2) 3 Si (OEt 3 ) 1.0 g Several drops of diethylamine 4.0 mL of i-propanol After completion of the dropwise addition, external heating was performed in the same manner as in Example 1. Hydrophobicity after treatment and triboelectric charge against iron
75% and +248 μC / g.
【００４８】次に、この処理で得た疎水性シリカを用い
て実施例１と同様に粒度の異なる２種類のトナーを調製
し、流動性試験を行ったところ、７μｍのトナーでは64
％、10μｍのトナーでは65％であった。さらに、これら
のトナー30ｇをそれぞれ酸化鉄粉1000ｇと混合して電子
写真用現像剤とした。この現像剤の摩擦帯電量はどちら
も＋17μC/ｇであった。本現像剤を市販の複写機に入
れ、寿命テストを行ったところ、約23,000枚以上のコピ
ーにおいても画像にカブリを生じなかった。さらに高温
多湿 (28℃、85％RH) の環境下においてもおいても同じ
テストを行ったところ、同様に良好な画像がほぼ同じ枚
数まで得られた。Next, two kinds of toners having different particle sizes were prepared using the hydrophobic silica obtained by this treatment in the same manner as in Example 1, and a fluidity test was carried out.
%, And 65% for a 10 μm toner. Further, 30 g of each of the toners was mixed with 1000 g of iron oxide powder to prepare an electrophotographic developer. The triboelectric charge of each developer was +17 μC / g. The developer was placed in a commercial copying machine and subjected to a life test. As a result, no fog occurred on the image even with about 23,000 or more copies. Further, the same test was carried out in a high-temperature and high-humidity environment (28 ° C., 85% RH).
【００４９】(実施例７)加熱乾燥させたシリカ粉体 (比
表面積130 m2/g) 20ｇに、実施例１と同様に下記組成の
処理剤を室温で噴霧した。Example 7 A treatment agent having the following composition was sprayed at room temperature on 20 g of silica powder (specific surface area: 130 m 2 / g) which had been dried by heating in the same manner as in Example 1.
【００５０】処理剤組成 疎水性シラン化合物 [(C6H13SiMe2)2NH] 2.0 ｇ アミノ置換シラン化合物 [H2N(CH2)3Si(OEt)3] 1.4 ｇ ジエチルアミン 数滴 ｉ−プロパノール 8.0 mL 滴下終了後、実施例１と同様に外部加熱を行った。処理
後の疎水化率および鉄に対する摩擦帯電量は、それぞれ
74％と＋256 μC/ｇであった。The treatment agent sets forming a hydrophobic silane compound [(C 6 H 13 SiMe 2 ) 2 NH] 2.0 g amino-substituted silane compound [H 2 N (CH 2) 3 Si (OEt) 3] 1.4 g of diethylamine few drops i After the addition of 8.0 mL of propanol, external heating was performed in the same manner as in Example 1. Hydrophobicity after treatment and triboelectric charge against iron
74% and +256 μC / g.
【００５１】次に、この処理で得た疎水性シリカを用い
て実施例１と同様に粒度の異なる２種類のトナーを調製
し、流動性試験を行ったところ、７μｍのトナーでは65
％、10μｍのトナーでは72％であった。さらに、これら
のトナー30ｇをそれぞれ酸化鉄粉1000ｇと混合して電子
写真用現像剤とした。この現像剤の摩擦帯電量はどちら
も＋17μC/ｇであった。本現像剤を市販の複写機に入
れ、寿命テストを行ったところ、約23,000枚以上のコピ
ーにおいても画像にカブリを生じなかった。さらに高温
多湿 (28℃、85％RH) の環境下においても同じテストを
行ったところ、同様に良好な画像がほぼ同じ枚数まで得
られた。Next, two kinds of toners having different particle sizes were prepared using the hydrophobic silica obtained by this treatment in the same manner as in Example 1, and a fluidity test was carried out.
%, And 72% for a 10 μm toner. Further, 30 g of each of the toners was mixed with 1000 g of iron oxide powder to prepare an electrophotographic developer. The triboelectric charge of each developer was +17 μC / g. The developer was placed in a commercial copying machine and subjected to a life test. As a result, no fog occurred on the image even with about 23,000 or more copies. Further, the same test was conducted in a high-temperature and high-humidity environment (28 ° C., 85% RH).
【００５２】(比較例１)加熱乾燥させたシリカ粉体 (比
表面積130 m2/g) 20ｇに、実施例１と同様に下記組成の
処理剤室温で噴霧した。Comparative Example 1 A treatment agent having the following composition was sprayed onto 20 g of the heat-dried silica powder (specific surface area: 130 m 2 / g) at room temperature in the same manner as in Example 1.
【００５３】処理剤組成 アミノ置換シラン化合物 [H2N(CH2)3Si(OEt)3] 1.0 ｇ ジエチルアミン 数滴 ｎ−プロパノール 5.0 mL 滴下終了後、実施例１と同様に外部加熱を行った。処理
後の疎水化率および鉄に対する摩擦帯電量は、それぞれ
18％と＋285 μC/ｇであった。次に、この処理で得た疎
水性シリカを用いて実施例１と同様に粒度の異なる２種
類のトナーを調製し、流動性試験を行ったところ、７μ
ｍのトナーでは26％、10μｍのトナーでは32％であっ
た。さらに、これらのトナー30ｇをそれぞれ酸化鉄粉10
00ｇと混合して電子写真用現像剤とした。この現像剤の
摩擦帯電量はどちらも＋18μC/ｇであった。[0053] processing Additives formed amino-substituted silane compound [H 2 N (CH 2) 3 Si (OEt) 3] 1.0 g of diethylamine few drops n- propanol 5.0 mL After the completion of dropwise addition, similarly to the external heating as in Example 1 performed Was. Hydrophobicity after treatment and triboelectric charge against iron
18% and +285 μC / g. Next, two kinds of toners having different particle sizes were prepared in the same manner as in Example 1 using the hydrophobic silica obtained by this treatment, and a fluidity test was performed.
The ratio was 26% for the m toner and 32% for the 10 μm toner. Further, 30 g of each of these toners was
This was mixed with 00 g to obtain an electrophotographic developer. The triboelectric charge of each developer was +18 μC / g.
【００５４】処理剤が疎水性シラン化合物を含んでいな
かったため、処理後のシリカ粉体の疎水性、トナー流動
性とも著しく低下した。本現像剤を市販の複写機に入
れ、寿命テストを行ったところ、約5,000 枚のコピーで
画像カブリを生じた。高温多湿 (28℃、85％RH) の環境
下ではさらに低下して、約4,000 枚のコピーで画像にカ
ブリを生じた。Since the treating agent did not contain a hydrophobic silane compound, the hydrophobicity of the treated silica powder and the fluidity of the toner were significantly reduced. When this developer was placed in a commercially available copying machine and subjected to a life test, image fogging occurred on about 5,000 copies. In a hot and humid environment (28 ° C, 85% RH), the temperature was further reduced, and the image was fogged after about 4,000 copies.
【００５５】(比較例２)加熱乾燥させたシリカ粉体 (比
表面積130 m2/g) 20ｇに、実施例１と同様に下記組成の
処理剤室温で噴霧した。Comparative Example 2 A treatment agent having the following composition was sprayed onto 20 g of the heat-dried silica powder (specific surface area: 130 m 2 / g) at room temperature in the same manner as in Example 1.
【００５６】処理剤組成 アミノ置換シラン化合物 [H2N(CH2)3Si(OEt)3] 1.0 ｇ ヘキサメチルジシラザン 1.0 ｇ ジエチルアミン 数滴 ｎ−プロパノール 5.0 mL 滴下終了後、実施例１と同様に外部加熱を行った。処理
後の疎水化率および鉄に対する摩擦帯電量は、それぞれ
44％と＋348 μC/ｇであった。次に、この処理で得た疎
水性シリカを用いて実施例１と同様に粒度の異なる２種
類のトナーを調製し、流動性試験を行ったところ、７μ
ｍのトナーでは62％、10μｍのトナーでは58％であっ
た。さらに、これらのトナー30ｇをそれぞれ酸化鉄粉10
00ｇと混合して電子写真用現像剤とした。この現像剤の
摩擦帯電量はどちらも＋18μC/ｇであった。[0056] processing Additives formed amino-substituted silane compound [H 2 N (CH 2) 3 Si (OEt) 3] 1.0 g of hexamethyldisilazane 1.0 g Diethylamine a few drops n- propanol 5.0 mL After the completion of dropwise addition, as in Example 1 Similarly, external heating was performed. Hydrophobicity after treatment and triboelectric charge against iron
44% and +348 μC / g. Next, two kinds of toners having different particle sizes were prepared in the same manner as in Example 1 using the hydrophobic silica obtained by this treatment, and a fluidity test was performed.
m was 62%, and 10% was 58%. Further, 30 g of each of these toners was
This was mixed with 00 g to obtain an electrophotographic developer. The triboelectric charge of each developer was +18 μC / g.
【００５７】本発明で用いる疎水性シラン化合物に代え
て、従来技術に従ってヘキサメチルジシラザンを使用し
た場合、流動性は本発明とあまり変化はないが、疎水化
率が60％よりかなり低く、疎水性は不十分であった。本
現像剤を市販の複写機に入れ、寿命テストを行ったとこ
ろ、約10,000枚のコピーで画像カブリを生じた。高温多
湿 (28℃、85％RH) の環境下ではさらに大きく低下し
て、約5,500 枚のコピーで画像にカブリを生じた。疎水
化剤がヘキサメチルジシラザンであると、疎水性が不安
定なため、高温多湿環境下での流動性の低下が著しいこ
とがわかる。When hexamethyldisilazane is used according to the prior art instead of the hydrophobic silane compound used in the present invention, the fluidity is not much different from that of the present invention, but the hydrophobicity is much lower than 60%, Sex was inadequate. The developer was placed in a commercially available copying machine and subjected to a life test. As a result, image fog occurred on about 10,000 copies. In a hot and humid environment (28 ° C, 85% RH), the fog was further reduced, and the image was fogged after approximately 5,500 copies. It can be seen that when the hydrophobizing agent is hexamethyldisilazane, the hydrophobicity is unstable, and the fluidity under a high-temperature and high-humidity environment is significantly reduced.
【００５８】(比較例３)加熱乾燥させたシリカ粉体 (比
表面積130 m2/g) 20ｇに、実施例１と同様に下記組成の
処理剤室温で噴霧した。Comparative Example 3 A treatment agent having the following composition was sprayed onto 20 g of the heat-dried silica powder (specific surface area: 130 m 2 / g) at room temperature in the same manner as in Example 1.
【００５９】処理剤組成 アミノ置換シラン化合物 [H2N(CH2)3Si(OEt)3] 1.0 ｇ ジメチルポリシロキサン [信越化学社製 KF-96 (50 cs)] 1.0 ｇ ジエチルアミン 数滴 ｎ−プロパノール 5.0 mL 滴下終了後、実施例１と同様に外部加熱を行った。処理
後の疎水化率および鉄に対する摩擦帯電量は、それぞれ
87％と＋385 μC/ｇであった。次に、この処理で得た疎
水性シリカを用いて実施例１と同様に粒度の異なる２種
類のトナーを調製し、流動性試験を行ったところ、７μ
ｍのトナーでは50％、10μｍのトナーでは54％であっ
た。さらに、これらのトナー30ｇをそれぞれ酸化鉄粉10
00ｇと混合して電子写真用現像剤とした。この現像剤の
摩擦帯電量はどちらも＋16μC/ｇであった。[0059] processing Additives formed amino-substituted silane compound [H 2 N (CH 2) 3 Si (OEt) 3] 1.0 g of dimethyl polysiloxane [Shin-Etsu Chemical Co., Ltd. KF-96 (50 cs)] 1.0 g of diethylamine few drops n After the addition of 5.0 mL of propanol, external heating was performed in the same manner as in Example 1. Hydrophobicity after treatment and triboelectric charge against iron
87% and +385 μC / g. Next, two kinds of toners having different particle sizes were prepared in the same manner as in Example 1 using the hydrophobic silica obtained by this treatment, and a fluidity test was performed.
m, 50%, and 10 μm, 54%. Further, 30 g of each of these toners was
This was mixed with 00 g to obtain an electrophotographic developer. The triboelectric charge of each developer was +16 μC / g.
【００６０】本発明で用いる疎水性シラン化合物に代え
て、別の従来技術に従って、シリコーン油の１種である
ジメチルポリシロキサンを使用した場合には、疎水性は
良好であるが、流動性が不十分であった。その理由はポ
リシロキサンがシリカ粉体の凝集を強めているためと推
測される。本現像剤を市販の複写機に入れ、寿命テスト
を行ったところ、約8,000 枚のコピーで画像にカブリを
生じた。高温多湿 (28℃、85％RH) の環境下ではさらに
低下して、約7,000 枚のコピーで画像にカブリを生じ
た。When dimethylpolysiloxane, which is a kind of silicone oil, is used according to another conventional technique in place of the hydrophobic silane compound used in the present invention, the hydrophobicity is good, but the fluidity is poor. Was enough. The reason is presumed to be that polysiloxane strengthens the aggregation of the silica powder. The developer was placed in a commercial copying machine and subjected to a life test. As a result, images were fogged after approximately 8,000 copies. In a hot and humid environment (28 ° C, 85% RH), the fog was further reduced, and the image was fogged after about 7,000 copies.
【００６１】[0061]
【発明の効果】以上の結果から明らかなように、本発明
に従って、疎水性シラン化合物とアミノ置換シラン化合
物との併用によるシリカ粉体の処理によって、鉄に対す
る適当な正の摩擦帯電量を持ち、透過率法により測定さ
れた疎水化率が60％以上である疎水性シリカを得ること
ができる。この処理を、シリカ粉体を浮遊状態にして行
うと、凝集がなく均一に処理された疎水性シリカを得る
ことができる。この疎水性シリカは、湿気のある環境で
も安定した疎水性を示し、トナーの流動性の改善効果が
高い。この疎水性シリカを流動性改善剤として電子写真
用のトナーに添加し、電子写真現像剤を作製すると、静
電荷像をカブリなく高いコントラストで鮮明に現像で
き、しかも、我が国の夏のように高温多湿の環境下にお
いても安定した長寿命の現像特性を持つ電子写真現像剤
が得られる。As is evident from the above results, according to the present invention, by treating silica powder with a combination of a hydrophobic silane compound and an amino-substituted silane compound, the silica powder has an appropriate positive triboelectric charge on iron, Hydrophobic silica having a hydrophobization rate of 60% or more measured by a transmittance method can be obtained. If this treatment is performed while the silica powder is in a floating state, it is possible to obtain a uniformly treated hydrophobic silica without aggregation. This hydrophobic silica shows stable hydrophobicity even in a humid environment, and has a high effect of improving the fluidity of the toner. When this hydrophobic silica is added to a toner for electrophotography as a fluidity improver to prepare an electrophotographic developer, an electrostatic image can be developed clearly with high contrast without fogging, and at a high temperature as in summer in Japan. An electrophotographic developer having stable and long life developing characteristics even in a humid environment can be obtained.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 加藤 由美 埼玉県大宮市北袋町１丁目297番地 三 菱マテリアル株式会社 中央研究所内 (56)参考文献 特開 平１−203478（ＪＰ，Ａ) 特開 平２−55206（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) C01B 33/113 - 33/193 G03G 9/08 ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yumi Kato 1-297 Kitabukuro-cho, Omiya-shi, Saitama Mitsui Materials Co., Ltd. Central Research Laboratory (56) References JP-A-1-203478 (JP, A) Hei 2-55206 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) C01B 33/113-33/193 G03G 9/08
Claims (3)
はアンモニアの存在下で、一般式(1) または(2) で示さ
れる疎水性有機ケイ素化合物と、一般式(3)で示される
アミノ置換シラン化合物とで表面処理された、透過率法
で測定した疎水化率が60％以上で、鉄に対して正の帯電
性を持った疎水性シリカ粉体。 一般式(1) ： R1 Si (R2)n (R3)3-n 一般式(2) ： R1 (R2)2 Si NH Si R1 (R2)2 一般式(3) ： (R4)x (R5)y Si (R6)z 式中、R1：炭素数３〜20のアルキル基、 R2：炭素数１〜20のアルキル基、 R3：Ｉ、Cl、Br、またはアルコキシル基、 R4：アミノ基を含有するアルキル基、 R5：炭素数１〜20のアルキル基、 R6：Ｉ、Cl、Br、またはアルコキシル基、 ｎ：０、１、または２、 ｘ：１〜３の整数、 ｙ：０、１、または２、 ｚ：１〜３の整数、 ｘ＋ｙ＋ｚ＝４。(1) in the presence of an organic amine as a catalyst or
Is surface-treated with a hydrophobic organosilicon compound represented by the general formula (1) or (2) and an amino-substituted silane compound represented by the general formula (3) in the presence of ammonia, and is measured by a transmittance method. Hydrophobic silica powder with a positive hydrophobicity to iron with a hydrophobicity of 60% or more. General formula (1): R 1 Si (R 2 ) n (R 3 ) 3-n General formula (2): R 1 (R 2 ) 2 Si NHSi R 1 (R 2 ) 2 General formula (3): (R 4 ) x (R 5 ) y Si (R 6 ) z wherein R 1 : an alkyl group having 3 to 20 carbon atoms, R 2 : an alkyl group having 1 to 20 carbon atoms, R 3 : I, Cl, Br or alkoxyl group, R 4 : amino group-containing alkyl group, R 5 : alkyl group having 1 to 20 carbon atoms, R 6 : I, Cl, Br or alkoxyl group, n: 0, 1, or 2 X: an integer of 1 to 3, y: 0, 1, or 2, z: an integer of 1 to 3, x + y + z = 4.
はアンモニアの存在下で、浮遊状態にあるシリカ粉体
を、請求項１記載の一般式(1) または(2) で示される疎
水性有機ケイ素化合物と、請求項１記載の一般式(3) で
示されるアミノ置換シラン化合物と接触させることから
なる、疎水性シリカ粉体の製造方法。2. A method according to claim 1, wherein said catalyst is an organic amine.
Is a method for preparing a silica powder in a suspended state in the presence of ammonia by mixing a hydrophobic organosilicon compound represented by the general formula (1) or (2) according to claim 1 with the water-soluble organosilicon compound represented by claim 1. In equation (3)
Comprising contacting an amino-substituted silane compound represented method of hydrophobicity silica powder.
することを特徴とする静電写真用現像剤。3. An electrophotographic developer comprising the hydrophobic silica powder according to claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP33679093A JP3319114B2 (en) | 1993-12-28 | 1993-12-28 | Hydrophobic silica powder, its production method and electrophotographic developer containing it |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP33679093A JP3319114B2 (en) | 1993-12-28 | 1993-12-28 | Hydrophobic silica powder, its production method and electrophotographic developer containing it |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07187647A JPH07187647A (en) | 1995-07-25 |
| JP3319114B2 true JP3319114B2 (en) | 2002-08-26 |
Family
ID=18302716
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP33679093A Expired - Lifetime JP3319114B2 (en) | 1993-12-28 | 1993-12-28 | Hydrophobic silica powder, its production method and electrophotographic developer containing it |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3319114B2 (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4704317B2 (en) * | 1996-12-26 | 2011-06-15 | 株式会社日本触媒 | Method for producing resin particles |
| US6190815B1 (en) * | 1998-08-11 | 2001-02-20 | Xerox Corporation | Toner compositions |
| TW396183B (en) * | 1998-11-20 | 2000-07-01 | Bayer Inc | Process for hydrophobicizing particles, and their use in dispersions |
| US6203960B1 (en) * | 2000-08-22 | 2001-03-20 | Xerox Corporation | Toner compositions |
| JP4743845B2 (en) * | 2005-04-15 | 2011-08-10 | テイカ株式会社 | Hydrophobic positively charged silica fine powder, method for producing the same, and toner for developing electrostatic latent image to which it is added as an external additive |
| US20070090052A1 (en) * | 2005-10-20 | 2007-04-26 | Broske Alan D | Chromatographic stationary phase |
| US20080070146A1 (en) | 2006-09-15 | 2008-03-20 | Cabot Corporation | Hydrophobic-treated metal oxide |
| CN102203678B (en) | 2008-10-29 | 2013-04-17 | 花王株式会社 | Electrophotographic toner |
| WO2010123099A1 (en) | 2009-04-23 | 2010-10-28 | 花王株式会社 | Electrophotographic toner |
| DE112010003903T5 (en) | 2009-10-01 | 2012-11-15 | Kao Corp. | Polyester for toner |
-
1993
- 1993-12-28 JP JP33679093A patent/JP3319114B2/en not_active Expired - Lifetime
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| Publication number | Publication date |
|---|---|
| JPH07187647A (en) | 1995-07-25 |
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