JP3686357B2 - Toner production method - Google Patents

Description

【００１５】
（式中、Ｒは炭素数２又は３のアルキレン基、ｘ及びｙは正の数を示し、ｘとｙの和は１〜１６、好ましくは１．５〜５．０である）で表される化合物が含有されていることが好ましい。
【００１６】
式（Ｉ）で表される化合物としては、ポリオキシプロピレン（２．２）−２，２−ビス（４−ヒドロキシフェニル）プロパン、ポリオキシエチレン（２．２）−２，２−ビス（４−ヒドロキシフェニル）プロパン等のビスフェノールＡのアルキレン（炭素数２〜３）オキサイド（平均付加モル数１〜１６）付加物等が挙げられる。また、他のアルコール成分としては、エチレングリコール、プロピレングリコール、グリセリン、ペンタエリスリトール、トリメチログリコールプロパン、水素添加ビスフェノールＡ、ソルビトール、又はそれらのアルキレン（炭素数２〜４）オキサイド（平均付加モル数１〜１６）付加物等が挙げられ、これらの１種以上を含有することが好ましい。
【００１７】
式（Ｉ）で表される化合物のアルコール成分中の含有量は、５モル％以上、好ましくは５０モル％以上、より好ましくは１００モル％が望ましい。
【００１８】
また、カルボン酸成分としては、フタル酸、イソフタル酸、テレフタル酸、フマル酸、マレイン酸等のジカルボン酸、ドデセニルコハク酸、オクチルコハク酸等の炭素数１〜２０のアルキル基又は炭素数２〜２０のアルケニル基で置換されたコハク酸、トリメリット酸、ピロメリット酸、それらの酸の無水物及びそれらの酸のアルキル（炭素数１〜３）エステル等が挙げられ、これらの１種以上を含有するものが好ましい。
【００１９】
ポリエステルは、例えば、アルコール成分、カルボン酸成分等を不活性ガス雰囲気中にて、要すればエステル化触媒を用いて、１８０〜２５０℃の温度で縮重合することにより製造することができる。
【００２０】
ポリエステルの酸価は１〜４０ｍｇＫＯＨ／ｇ、水酸基価は３〜６０ｍｇＫＯＨ／ｇ、溶融温度は９５〜１４０℃、ガラス転移点は５２〜７５℃であることが、それぞれ好ましい。
【００２１】
着色剤としては、トナー用着色剤として用いられている染料、顔料等のすべてを使用することができ、カーボンブラック、フタロシアニンブルー、パーマネントブラウンFG、プリリアントファーストスカーレット、ピグメントグリーンB 、ローダミン−B ベース、ソルベントレッド49、ソルベントレッド146 、ソルベントブルー35、キナクリドン、カーミン6B、ジスアゾエロー等が挙げられ、これらは単独で又は２種以上を混合して用いることができ、本発明において、トナーは黒トナー、カラートナー、フルカラートナーのいずれであってもよい。着色剤の含有量は、結着樹脂１００重量部に対して、１〜４０重量部が好ましく、３〜１０重量部がより好ましい。
【００２２】
さらに、組成物には、荷電制御剤、離型剤、流動性向上剤、導電性調整剤、体質顔料、繊維状物質等の補強充填剤、酸化防止剤、老化防止剤、クリーニング性向上剤等の添加剤が適宜含有されていてもよい。
【００２３】
結着樹脂、着色剤及びワックスを含有した組成物は、ヘンシェルミキサー等で予備混合した後に、溶融混練に供するのが好ましい。
【００２４】
組成物の溶融混練には、密閉式ニーダー、１軸又は２軸の押出機等を用いることができるが、本発明では、加熱機能及び冷却機能を有するオープンロール型連続混練機を用いるのが好ましい。オープンロール型連続混練機は、２本のロールが並行に近接して配設された混練機であり、各ロールは、熱媒体を通すことにより加熱又は冷却を行うことができる。かかるオープンロール型連続混練機は、加熱ロールと冷却ロールを備えていることから、また、溶融混練する部分がオープン型であることから、溶融混練の際に発生する混練熱を容易に放熱することができる。
【００２５】
溶融混練は、混練物の温度が、Ｔｍ−２０℃〜Ｔｍ＋２０℃、より好ましくはＴｍ−１０℃〜Ｔｍ＋１０℃となる条件で行うのが好ましい。なお、本発明において、混練物の温度とは、ロールに付着した混練物自体の温度を指し、非接触式レーザー型温度計で測定する。
【００２６】
溶融温度（Ｔｍ）は、高化式フローテスター（ＣＦＴ−５００、島津製作所（株）製）を用い、ダイスの細孔の径１ｍｍ、長さ１ｍｍ、荷重１９６Ｎ／ｃｍ² 、昇温速度６℃／ｍｉｎの条件下で１ｃｍ³ の試料を溶融流出させたときの流出開始点から流出終了点の高さの１／２に相当する温度とする。
【００２７】
２本のロールの間隙は、好ましくは０．１〜１０ｍｍ、更に好ましくは０．１〜３ｍｍである。また、各ロールの構造、大きさ、材料等について特に限定はなく、ロール表面は、平滑であってもよく、波型、凸凹型等であってもよい。
【００２８】
また、ロールの回転数は、周速度２〜１００ｍ／ｍｉｎであることが好ましい。また、２本のロールの回転数比は、１／１０〜９／１０（冷却ロール／加熱ロール）であることが好ましい。
【００２９】
溶融混練により得られた混練物を、前記圧延比となるように圧延し、冷却する。圧延、冷却の方法は特に限定されない。圧延手段としては、圧延ロールや圧延ドラム等が、冷却手段としては、空冷方式、水冷方式、スチール製の冷却ベルト方式等が、それぞれ挙げられるが、例えば、図１や図２に示すような圧延装置付き冷却機を用いてもよい。図１に示す装置では、圧延ロール１で混練物２を圧延した後、冷却ベルト３上で冷却、またはさらに冷風を送ることにより冷却することができ、また図２に示す装置では、圧延ドラム４で混練物２を圧延した後、冷却ベルト５、６に挟み込んで冷却することができるので、圧延ドラム通過直後、樹脂膨張が生じることなく、冷却での混練物の厚みを安定に調整することができる。圧延ロールや圧延ドラムの間隔を調整することにより、圧延後の厚みを調整することができる。
【００３０】
圧延後、冷却に供される混練物の厚みは、ワックスの分散粒径を維持するために、３ｍｍ以上が好ましく、４〜６ｍｍがより好ましい。
【００３１】
圧延冷却後の混練物中のワックスの平均粒径の増大率は、高い耐刷印字性能や印字光沢を得るために、２倍以下が好ましく、１〜１．５倍がより好ましい。なお、平均粒径の増大率とは、実施例に示すように、溶融混練後、得られた混練物を圧延せずに冷却した混練物中のワックスの平均粒径に対する圧延冷却後の混練物中のワックスの平均粒径の比をいう。
【００３２】
圧延し、冷却した混練物を、粉砕、分級等の公知の工程でさらに処理することにより、トナーを製造することができる。
【００３３】
粉砕に用いられる粉砕装置としては、例えば、ジェットミル、衝突板式ミル、回転型機械ミル等が挙げられる。
【００３４】
分級に用いられる分級装置としては、例えば、風力分級機、慣性式分級機、篩式分級機等が挙げられる。
【００３５】
トナーの重量平均粒径は、５〜１５μｍが好ましく、トナーの表面には、さらに疎水性シリカ等の流動性向上剤等が外添剤として添加されていてもよい。重量平均粒径は実施例に示す方法により求められる。
【００３６】
トナー中のワックスの平均粒径は、高い耐刷印字性能や印刷光沢を得るために、０．１〜１μｍが好ましく、０．１〜０．５μｍがより好ましい。本発明により得られるトナーは、ワックスが微細に分散しているため、印刷光沢に優れた画像が得られる。
【００３７】
本発明により得られるトナーは、磁性体微粉末を含有するときは単独で現像剤として、また磁性体微粉末を含有しないときは非磁性一成分系現像剤として、もしくはキャリアと混合して二成分系現像剤として使用することができる。
【００３８】
【実施例】
〔ガラス転移点〕
示差走査熱量計「ＤＳＣ２１０」（セイコー電子工業社製）を用いて昇温速度１０℃／分で測定する。
【００３９】
〔トナー中のワックスの平均粒径〕
トナー中のワックス粒子を透過型電子顕微鏡写真（２５００倍）にて２００個程度観察して、以下の式（１）に基づいて平均粒径を算出する。
【００４０】
【数１】

【００４１】
実施例１、比較例１、２
・ポリエステル樹脂（ガラス転移点：６１℃、Ｔｍ：１２４℃）
１００重量部
（酸成分：テレフタル酸４２重量部、トリメリット酸３４重量部、ドデセニルコハク酸２４重量部；アルコール成分：ポリオキシエチレン（２．０）−２，２−ビス（４−ヒドロキシフェニル）プロパン２８重量部、ポリオキシプロピレン（２．２）−２，２−ビス（４−ヒドロキシフェニル）プロパン７２重量部）
・銅フタロシアニン顔料（Ｃ．Ｉ．ピグメント・ブルー (C. I. Pigment Blue) １５：３） ３重量部
・カルナバワックス １０重量部
以上の原料からなる組成物１５ｋｇを、ヘンシェルミキサー（有効容量：７５リットル）を用い、羽根回転数を１２００回転／分にて３分間混合した後、テーブルフィーダーにて、オープンロール型連続混練機「ニーデックス」（三井鉱山（株）製）に供給して溶融混練した。
【００４２】
溶融混練にした使用したオープンロール型連続混練機は、ロール外径０．１４〔ｍ〕、有効ロール長０．８〔ｍ〕のものであり、運転条件は、高回転側ロール（前ロール）回転数７５回転／分、低回転側ロール（後ロール）回転数５０回転／分、ロール間隙０．０００１〔ｍ〕であった。ロール内の加熱及び冷却媒体温度は、高回転ロールの原料投入側温度１５０℃、混練物排出側温度１００℃、低回転ロールの温度３０℃に設定した。ロールに付着した混練物の温度は、原料投入側では１２６℃、混練物排出側では１１５℃であり、排出直後の混練物温度は１１１℃であった。また、原料混合物の供給速度は２０ｋｇ／時、平均滞留時間は約５分間であった。
【００４３】
次に、混練物を、表１に示す条件で圧延装置付き冷却機を用いて圧延し、冷却した。なお、圧延装置付き冷却機Ａ、Ｂの概略構造図はそれぞれ図１、２に相当する。具体的には、圧延装置付き冷却機Ａは、直径１８０ｍｍのジャケット付きの圧延ロール１と冷風噴き出し口を上部に配したゴム製の冷却ベルト３で構成されている。圧延ロール１のジャケットには６５℃の温水を通水した。冷却ベルト３は搬送速度２ｍ／ｍｉｎで運転し、圧延ロール１の回転速度は該圧延ロールの周端速度が冷却ベルト３の搬送速度と同一になるようにして運転した。一方、圧延装置付き冷却機Ｂは、冷却機構を有していない直径６００ｍｍの圧延ドラム４に厚さ１ｍｍのステンレススチール製の冷却ベルト５、６が巻かれている。下側の冷却ベルト５と上側の冷却ベルト６はそれぞれ１５℃の水で水冷されており、圧延ドラム４で圧延された混練物はそのまま冷却ベルト５、６に挟み込まれて冷却ベルトにより上下両側から冷却される。冷却ベルト５、６の搬送速度は１．９ｍ／ｍｉｎに設定して冷却を行なった。
【００４４】
冷却した混練物を粉砕、分級し、重量平均粒径が９μｍのトナーを得た。なお、トナーの重量平均粒径は、コールターカウンターにて測定した。得られたトナー１００重量部に対し、コロイダルシリカ２重量部を外添して、現像剤とした。
【００４５】
トナー中のワックスの平均粒径とその増大率を表１に示す。なお、圧延前つまり溶融混練後の混練物を、圧延せずに、常温で放置冷却した混練物中のワックスの平均粒径は０．１７μｍであった。
【００４６】
試験例１
実施例及び比較例で得られたトナーを、「ＬＳ−１５５０」（京セラ（株）製）に実装し、画像出しを行った。得られた画像の光沢度をグロスチェッカー「ＩＧ−３３０」（堀場製作所（株）製）を用いて、入射角度６０°で測定し、以下の評価基準により評価した。結果を表１に示す。
【００４７】
〔評価基準〕
◎：１３％以上 ○：１０％以上、１３％未満 ×：１０％未満
【００４８】
【表１】

【００４９】
圧延比を所定の範囲内に調整した実施例１では、トナー中のワックスが微細に分散し、優れた光沢性が得られている。これに対し、比較例１、２は、圧延比が調整されていないため、トナー中のワックスの分散径が大きく、光沢性に欠ける。
【００５０】
【発明の効果】
本発明により、ワックスが微細に分散し、光沢性に優れたトナーを製造することができる。
【図面の簡単な説明】
【図１】図１は、本発明に用いられる圧延装置付き冷却機の一実施態様を示す概略構造図である。
【図２】図２は、本発明に用いられる圧延装置付き冷却機の一実施態様を示す概略構造図である。
【符号の説明】
１ 圧延ロール
２ 混練物
３ 冷却ベルト
４ 圧延ドラム
５ 冷却ベルト
６ 冷却ベルト[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like.
[0002]
[Prior art]
Optimizing the gloss of the printed surface is one of the important issues particularly in full-color printing. Conventionally, the printing gloss varies depending on the type and / or composition of the binder resin constituting the toner, but the printing gloss cannot be controlled due to limitations such as fixing characteristics, and there is a means for improving the printing gloss in the manufacturing stage. unknown.
[0003]
On the other hand, in full-color printing, many techniques for blending wax into toner as an anti-offset agent have been disclosed. Although it is well known that the amount of wax increases and filming is caused by adhering to the photoreceptor in the developing machine, this increases the amount of wax added and the dispersion state of the wax in the toner. This is because it becomes difficult to maintain in kneading and cooling.
[0004]
In order to solve such a problem, in Japanese Patent No. 3094695, the twin screw extruder is kneaded in the range of Tm-20 ° C. to Tm + 20 ° C. (where Tm is the melting temperature of the binder resin, the same applies hereinafter). Japanese Patent Application Laid-Open No. 2000-75548 discloses a toner having a process of melt kneading using an open roll type continuous kneader at a temperature of Tm-20 ° C. to Tm + 20 ° C. A manufacturing method is disclosed. However, even if the wax mixed in the toner is sufficiently dispersed in the kneading step, the dispersion state of the wax deteriorates unless the cooling method is appropriate.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to provide a toner production method in which wax is finely dispersed and excellent in gloss.
[0006]
[Means for Solving the Problems]
In the production of toner, in consideration of the productivity of the cooling process, the inventors can increase the cooling efficiency of the kneaded product by rolling the kneaded product to increase the cooling area. It was found that the wax dispersed by reaggregation causes the dispersibility of the wax to deteriorate. Then, the manufacturing method which achieves the high dispersibility of wax was discovered by paying attention to rolling and a cooling process. Furthermore, the dispersibility of the wax and the print gloss are closely related, and it has been found that the print gloss is drastically improved by finely dispersing the wax in the toner by the production method of the present invention.
[0007]
The present invention is a binder resin, a composition containing a colorant and a wax, a 5-20 parts by weight the composition heating function and relative to 100 parts by weight of binder resin content of the wax The kneaded product obtained by melt-kneading using an open roll type continuous kneader having a cooling function has a rolling ratio (thickness of kneaded product after rolling / thickness of kneaded product before rolling) of 0.4 or more. rolled under conditions such that less than 1, have a step for cooling, the kneaded product to an average particle diameter of the wax in the kneaded material after the rolling cooling to the average particle diameter of the wax in the kneaded product was cooled without rolling the method for producing a toner increase rate Ru der 2 times or less.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, when the composition containing the binder resin, the colorant and the wax is melt-kneaded, the rolling ratio (thickness of the kneaded product after rolling / thickness of the kneaded product before rolling) is 0.4 or more. Rolling is performed under conditions of less than 1, preferably 0.6 to less than 1, more preferably 0.8 to less than 1, and cooling is performed. By adjusting the rolling ratio, wax aggregation is suppressed, and a toner having excellent wax dispersibility and high printing gloss can be obtained.
[0009]
The content of the wax is 3 to 20 parts by weight, preferably 5 to 15 parts by weight, and more preferably 5 to 10 parts by weight with respect to 100 parts by weight of the binder resin. Usually, when the wax content increases, the wax aggregated in the toner adheres to the photoreceptor and causes filming. However, in the present invention, since the wax can be finely dispersed in the toner, even if the wax is contained in a large amount, a toner having further excellent print gloss can be obtained without causing filming.
[0010]
Examples of the wax include natural waxes such as carnauba wax and rice wax, synthetic waxes such as polypropylene wax, polyethylene wax and Fischer Tropu, coal-based waxes such as montan wax, alcohol-based waxes, ester-based waxes, etc. Carnauba wax is preferable because it may be used alone or in combination of two or more thereof, and it is easy to bleed out quickly.
[0011]
Examples of the binder resin include polyester, styrene-acrylic resin, epoxy resin, polycarbonate, polyurethane, and the like. Among these, polyester is preferable from the viewpoint of low-temperature fixing performance. The content of the polyester is preferably 50 to 100% by weight, more preferably 90 to 100% by weight, and particularly preferably 100% by weight in the binder resin.
[0012]
As a raw material monomer for polyester, a known divalent or higher valent alcohol component and a known carboxylic acid component such as a divalent or higher carboxylic acid, carboxylic acid anhydride, or carboxylic acid ester are used.
[0013]
As the alcohol component, the formula (I):
[0014]
[Chemical 1]

[0015]
(Wherein R is an alkylene group having 2 or 3 carbon atoms, x and y are positive numbers, and the sum of x and y is 1 to 16, preferably 1.5 to 5.0). It is preferable that the compound is contained.
[0016]
Examples of the compound represented by the formula (I) include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4 -Alkylene (2 to 3 carbon atoms) oxide (average number of added moles 1 to 16) adduct of bisphenol A such as -hydroxyphenyl) propane. Other alcohol components include ethylene glycol, propylene glycol, glycerin, pentaerythritol, trimethyloglycol propane, hydrogenated bisphenol A, sorbitol, or alkylene (2 to 4 carbon atoms) oxide (average added mole number 1). -16) Additives etc. are mentioned, It is preferable to contain 1 or more types of these.
[0017]
The content of the compound represented by the formula (I) in the alcohol component is 5 mol% or more, preferably 50 mol% or more, more preferably 100 mol%.
[0018]
The carboxylic acid component includes dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, fumaric acid and maleic acid, alkyl groups having 1 to 20 carbon atoms such as dodecenyl succinic acid and octyl succinic acid, or those having 2 to 20 carbon atoms. Examples thereof include succinic acid, trimellitic acid, pyromellitic acid substituted with an alkenyl group, anhydrides of these acids, and alkyl (carbon number of 1 to 3) esters of these acids, and one or more of these are contained. Those are preferred.
[0019]
The polyester can be produced, for example, by subjecting an alcohol component, a carboxylic acid component and the like in an inert gas atmosphere, if necessary, using an esterification catalyst at a temperature of 180 to 250 ° C.
[0020]
The polyester preferably has an acid value of 1 to 40 mgKOH / g, a hydroxyl value of 3 to 60 mgKOH / g, a melting temperature of 95 to 140 ° C, and a glass transition point of 52 to 75 ° C.
[0021]
As the colorant, all of the dyes and pigments used as toner colorants can be used, such as carbon black, phthalocyanine blue, permanent brown FG, preferential first scarlet, pigment green B, rhodamine-B base. Solvent Red 49, Solvent Red 146, Solvent Blue 35, Quinacridone, Carmine 6B, Disazo Yellow, etc., and these can be used alone or in admixture of two or more. In the present invention, the toner is black toner, Either color toner or full color toner may be used. The content of the colorant is preferably 1 to 40 parts by weight and more preferably 3 to 10 parts by weight with respect to 100 parts by weight of the binder resin.
[0022]
Further, the composition includes a charge control agent, a release agent, a fluidity improver, a conductivity modifier, an extender pigment, a reinforcing filler such as a fibrous substance, an antioxidant, an anti-aging agent, a cleaning property improver, etc. These additives may be contained as appropriate.
[0023]
The composition containing the binder resin, the colorant and the wax is preferably subjected to melt kneading after premixing with a Henschel mixer or the like.
[0024]
For melt kneading of the composition, a closed kneader, a uniaxial or biaxial extruder can be used, but in the present invention, it is preferable to use an open roll type continuous kneader having a heating function and a cooling function. . The open roll type continuous kneader is a kneader in which two rolls are arranged close to each other in parallel, and each roll can be heated or cooled by passing a heat medium. Such an open roll type continuous kneader is provided with a heating roll and a cooling roll, and since the part to be melt kneaded is an open type, it can easily dissipate the kneading heat generated during melt kneading. Can do.
[0025]
The melt-kneading is preferably performed under the condition that the temperature of the kneaded product is Tm-20 ° C to Tm + 20 ° C, more preferably Tm-10 ° C to Tm + 10 ° C. In the present invention, the temperature of the kneaded product refers to the temperature of the kneaded product itself attached to the roll, and is measured with a non-contact type laser thermometer.
[0026]
The melting temperature (Tm) is a Koka-type flow tester (CFT-500, manufactured by Shimadzu Corporation). The diameter of the pore of the die is 1 mm, the length is 1 mm, the load is 196 N / cm ² , and the heating rate is 6 ° C. A temperature corresponding to ½ of the height of the outflow end point from the outflow start point when a sample of 1 cm ³ is melted out under the condition of / min.
[0027]
The gap between the two rolls is preferably 0.1 to 10 mm, more preferably 0.1 to 3 mm. Moreover, there is no limitation in particular about the structure of each roll, a magnitude | size, material, etc. The roll surface may be smooth and may be a corrugated form, an uneven shape.
[0028]
Moreover, it is preferable that the rotation speed of a roll is 2-100 m / min of peripheral speeds. Further, the rotation speed ratio of the two rolls is preferably 1/10 to 9/10 (cooling roll / heating roll).
[0029]
The kneaded product obtained by melt kneading is rolled so as to have the rolling ratio and cooled. The method of rolling and cooling is not particularly limited. Examples of the rolling means include a rolling roll and a rolling drum, and examples of the cooling means include an air cooling method, a water cooling method, and a steel cooling belt method. For example, rolling as shown in FIGS. You may use the cooler with an apparatus. In the apparatus shown in FIG. 1, after rolling the kneaded material 2 with the rolling roll 1, it can be cooled by cooling on the cooling belt 3 or further by sending cold air. In the apparatus shown in FIG. After the kneaded product 2 is rolled by the above method, the kneaded product 2 can be cooled by being sandwiched between the cooling belts 5 and 6, so that the thickness of the kneaded product in the cooling can be stably adjusted without causing resin expansion immediately after passing through the rolling drum. it can. The thickness after rolling can be adjusted by adjusting the interval between the rolling rolls and the rolling drum.
[0030]
The thickness of the kneaded product to be cooled after rolling is preferably 3 mm or more, more preferably 4 to 6 mm in order to maintain the dispersed particle diameter of the wax.
[0031]
The increase rate of the average particle diameter of the wax in the kneaded product after rolling and cooling is preferably 2 times or less, more preferably 1 to 1.5 times, in order to obtain high printing durability and printing gloss. The rate of increase in the average particle size is, as shown in the examples, the kneaded product after rolling and cooling with respect to the average particle size of the wax in the kneaded product obtained by melting and kneading and cooling the obtained kneaded product without rolling. The ratio of the average particle diameter of the wax inside.
[0032]
The toner can be produced by further processing the rolled and cooled kneaded material by known processes such as pulverization and classification.
[0033]
Examples of the pulverizer used for pulverization include a jet mill, a collision plate mill, and a rotary mechanical mill.
[0034]
Examples of the classifier used for classification include an air classifier, an inertia classifier, and a sieve classifier.
[0035]
The weight average particle diameter of the toner is preferably 5 to 15 μm, and a fluidity improver such as hydrophobic silica may be further added to the toner surface as an external additive. A weight average particle diameter is calculated | required by the method shown in an Example.
[0036]
The average particle size of the wax in the toner is preferably from 0.1 to 1 μm, more preferably from 0.1 to 0.5 μm, in order to obtain high printing durability and printing gloss. Since the toner obtained by the present invention has finely dispersed wax, an image excellent in printing gloss can be obtained.
[0037]
When the toner obtained by the present invention contains a magnetic fine powder, the toner alone is used as a developer, and when it does not contain a magnetic fine powder, the toner is a non-magnetic one-component developer or mixed with a carrier to form a two-component. It can be used as a system developer.
[0038]
【Example】
[Glass transition point]
A differential scanning calorimeter “DSC210” (manufactured by Seiko Denshi Kogyo Co., Ltd.) is used for measurement at a heating rate of 10 ° C./min.
[0039]
[Average particle size of wax in toner]
About 200 wax particles in the toner are observed with a transmission electron micrograph (2500 times magnification), and the average particle diameter is calculated based on the following formula (1).
[0040]
[Expression 1]

[0041]
Example 1, Comparative Examples 1 and 2
Polyester resin (Glass transition point: 61 ° C, Tm: 124 ° C)
100 parts by weight (acid component: 42 parts by weight of terephthalic acid, 34 parts by weight of trimellitic acid, 24 parts by weight of dodecenyl succinic acid; alcohol component: polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane 28 parts by weight, 72 parts by weight of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane)
・ Copper phthalocyanine pigment (CI Pigment Blue 15: 3) 3 parts by weight ・ Carnauba wax 10 parts by weight Using a Henschel mixer (effective capacity: 75 liters) The mixture was mixed for 3 minutes at a blade rotation speed of 1200 rpm, and then supplied to an open roll type continuous kneader “NIDEX” (manufactured by Mitsui Mining Co., Ltd.) with a table feeder and melt-kneaded.
[0042]
The open roll type continuous kneader used for melt kneading has a roll outer diameter of 0.14 [m] and an effective roll length of 0.8 [m], and operating conditions are a high rotation side roll (front roll). The rotation number was 75 rotations / minute, the low rotation side roll (rear roll) rotation number was 50 rotations / minute, and the roll gap was 0.0001 [m]. The heating and cooling medium temperatures in the roll were set to a raw material input side temperature of 150 ° C. for the high rotation roll, a kneaded product discharge side temperature of 100 ° C., and a low rotation roll temperature of 30 ° C. The temperature of the kneaded material adhering to the roll was 126 ° C. on the raw material charging side and 115 ° C. on the kneaded material discharging side, and the kneaded material temperature immediately after discharging was 111 ° C. The feed rate of the raw material mixture was 20 kg / hour, and the average residence time was about 5 minutes.
[0043]
Next, the kneaded material was rolled using a cooler with a rolling device under the conditions shown in Table 1 and cooled. The schematic structural diagrams of the coolers A and B with a rolling device correspond to FIGS. Specifically, the cooler A with a rolling device is composed of a rolling roll 1 with a jacket having a diameter of 180 mm and a rubber cooling belt 3 having a cold air jet port disposed at the top thereof. Hot water of 65 ° C. was passed through the jacket of the roll 1. The cooling belt 3 was operated at a conveyance speed of 2 m / min, and the rotation speed of the rolling roll 1 was operated such that the peripheral end speed of the rolling roll was the same as the conveyance speed of the cooling belt 3. On the other hand, in the cooler B with a rolling device, cooling belts 5 and 6 made of stainless steel having a thickness of 1 mm are wound around a rolling drum 4 having a diameter of 600 mm that does not have a cooling mechanism. The lower cooling belt 5 and the upper cooling belt 6 are each water-cooled with water at 15 ° C., and the kneaded material rolled by the rolling drum 4 is sandwiched between the cooling belts 5 and 6 as it is from both the upper and lower sides by the cooling belt. To be cooled. The cooling speed of the cooling belts 5 and 6 was set to 1.9 m / min for cooling.
[0044]
The cooled kneaded product was pulverized and classified to obtain a toner having a weight average particle diameter of 9 μm. The weight average particle diameter of the toner was measured with a Coulter counter. A developer was prepared by externally adding 2 parts by weight of colloidal silica to 100 parts by weight of the obtained toner.
[0045]
Table 1 shows the average particle diameter of wax in the toner and the increase rate. The average particle size of the wax in the kneaded product, which was cooled before standing at room temperature without rolling the kneaded product before rolling, that is, after melt-kneading, was 0.17 μm.
[0046]
Test example 1
The toners obtained in Examples and Comparative Examples were mounted on “LS-1550” (manufactured by Kyocera Corporation), and images were taken out. The glossiness of the obtained image was measured at an incident angle of 60 ° using a gloss checker “IG-330” (manufactured by Horiba, Ltd.) and evaluated according to the following evaluation criteria. The results are shown in Table 1.
[0047]
〔Evaluation criteria〕
◎: 13% or more ○: 10% or more, less than 13% ×: less than 10%
[Table 1]

[0049]
In Example 1, was adjusted rolling ratio within a predetermined range, the wax in the toner is dispersed finely, and provides excellent gloss. On the other hand, in Comparative Examples 1 and 2, since the rolling ratio is not adjusted, the dispersion diameter of the wax in the toner is large and the glossiness is lacking.
[0050]
【The invention's effect】
According to the present invention, a toner in which wax is finely dispersed and excellent in glossiness can be produced.
[Brief description of the drawings]
FIG. 1 is a schematic structural diagram showing an embodiment of a cooling machine with a rolling device used in the present invention.
FIG. 2 is a schematic structural diagram showing one embodiment of a cooling machine with a rolling device used in the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Roll roll 2 Kneaded material 3 Cooling belt 4 Rolling drum 5 Cooling belt 6 Cooling belt

Claims (3)

A composition containing a binder resin, a colorant and a wax, wherein the composition having a wax content of 5 to 20 parts by weight with respect to 100 parts by weight of the binder resin has a heating function and a cooling function. The kneaded product obtained by melt-kneading using an open roll type continuous kneader has a rolling ratio (thickness of the kneaded product after rolling / thickness of the kneaded product before rolling) of 0.4 or more and less than 1. rolled under the conditions, it has a step for cooling, increase in the average particle diameter of the wax in the kneaded material after the rolling cooling to the average particle diameter of the wax in the kneaded product was cooled without rolling the kneaded product 2 method of manufacturing a double Ru der less toner.   The manufacturing method according to claim 1, wherein the rolled kneaded material is cooled with a thickness of 3 mm or more. The method according to claim 1 or 2 , wherein the average particle size of the wax in the obtained toner is 0.1 to 1 µm.

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