JP2013025294A5

JP2013025294A5 -

Info

Publication number: JP2013025294A5
Application number: JP2011163157A
Authority: JP
Filing date: 2011-07-26
Publication date: 2014-09-04
Anticipated expiration: 2031-07-26

Description

本発明は、ポリエステルを主成分とする樹脂、磁性酸化鉄およびワックスを、酢酸エチルに溶解または分散させて得られた組成物を水系媒体中に分散させ、ついで酢酸エチルを除去することによって得られる磁性トナー粒子と、無機微粒子とを有する磁性トナーであって、
前記磁性酸化鉄２０ｇを酢酸エチル３０ｇに分散させた後、静置し、沈澱体積の減少速度を評価する試験において、静置５分後の液面体積を（Ａ０）、沈澱体積を（Ａ５）としたとき、Ａ０に対するＡ５の割合（＝（Ａ５／Ａ０）×１００）が、５０％以上８５％以下であることを特徴とする磁性トナーに関する。 The present invention is obtained by dispersing a composition obtained by dissolving or dispersing a polyester-based resin, magnetic iron oxide and wax in ethyl acetate in an aqueous medium, and then removing the ethyl acetate. A magnetic toner having magnetic toner particles and inorganic fine particles,
In a test in which 20 g of the magnetic iron oxide was dispersed in 30 g of ethyl acetate and allowed to stand to evaluate the rate of decrease in the precipitation volume, the liquid level volume after standing for 5 minutes was (A0) and the precipitation volume was (A5). The ratio of A5 to A0 (= (A5 / A0) × 100) is 50% or more and 85% or less.

Claims

A magnetic toner particle obtained by dispersing a composition obtained by dissolving or dispersing a polyester-based resin, magnetic iron oxide and wax in ethyl acetate in an aqueous medium and then removing the ethyl acetate; A magnetic toner having inorganic fine particles,
In a test in which 20 g of the magnetic iron oxide was dispersed in 30 g of ethyl acetate and allowed to stand to evaluate the rate of decrease in the precipitation volume, the liquid level volume after standing for 5 minutes was (A0) and the precipitation volume was (A5). The magnetic toner is characterized in that the ratio of A5 to A0 (= (A5 / A0) × 100) is 50% or more and 85% or less.

The magnetic iron oxide, after dispersing the magnetic iron oxide 20g of isopropyl alcohol 30g, standing, in tests to evaluate the decrease rate of the precipitation volume, the liquid level volume 5 minutes after standing (I0), when the precipitate volume and (I5), (I5 / I0) and (A5 / A0), but the magnetic toner according to claim 1, characterized in that it satisfies the relationship of formula (1).
1.10 ≦ (I5 / I0) / (A5 / A0) ≦ 2.00 (1)

The magnetic iron oxide contains a Ti component, an Al component, and a Si component,
The content of the Ti component is 0.30 mass% or more and 5.00 mass% or less with respect to the whole magnetic iron oxide in terms of Ti element,
The content of the Al component is 0.10% by mass or more and 3.00% by mass or less with respect to the entire magnetic iron oxide in terms of Al element,
3. The magnetic property according to claim 1, wherein a content of the Si component is 0.10% by mass or more and 5.00% by mass or less with respect to the entire magnetic iron oxide in terms of Si element. toner.

(1) The amount of Al component eluted when the magnetic iron oxide is added to an alkaline aqueous solution and the Al component contained in the magnetic iron oxide is eluted with the alkaline aqueous solution is the total amount of Al component contained in the magnetic iron oxide. 50% to 95% of the ratio of
(2) The amount of Fe element contained in the solution when the Al component contained in the magnetic iron oxide is dissolved in the alkaline aqueous solution and the magnetic iron oxide is dissolved in the acid aqueous solution after the elution of the alkaline solution and dissolved in the aqueous solution. Is the total Fe element amount, the amount of Al component contained in the solution at which 10% by mass of the Fe element is dissolved (hereinafter referred to as the Fe element dissolution rate 10% by mass solution). And the total proportion of the amount of Al component eluted in (1) is 95% or more of the total amount of Al component contained in the magnetic iron oxide,
(3) Ratio of Ti component content (Ti element conversion value) to Al component content (Al element conversion value) contained in the 10 mass% Fe element dissolution rate solution (Ti component content ( 4. The magnetic toner according to claim 3, wherein Ti element conversion value) / Al component content (Al element conversion value) is 2.0 or more and 30.0 or less.

4. The amount of Si component eluted when the magnetic iron oxide is added to an alkaline aqueous solution and the Si component contained in the magnetic iron oxide is eluted with the alkaline aqueous solution is the total amount of Si components contained in the magnetic iron oxide. The magnetic toner according to claim 3, wherein the magnetic toner is 0% or more and 30.0% or less.

Ratio of Ti component content (Ti element conversion value) to Si component content (Si element conversion value) contained in the 10 mass% Fe element dissolution rate solution (Ti component content (Ti element conversion value) The magnetic toner according to claim 3, wherein (value) / content of Si component (Si element conversion value) is 1.0 or more and 5.0 or less.