JP7415220B2 - Agglomerated iron oxide particles powder - Google Patents
Agglomerated iron oxide particles powder Download PDFInfo
- Publication number
- JP7415220B2 JP7415220B2 JP2019180571A JP2019180571A JP7415220B2 JP 7415220 B2 JP7415220 B2 JP 7415220B2 JP 2019180571 A JP2019180571 A JP 2019180571A JP 2019180571 A JP2019180571 A JP 2019180571A JP 7415220 B2 JP7415220 B2 JP 7415220B2
- Authority
- JP
- Japan
- Prior art keywords
- iron oxide
- agglomerated
- particles
- present
- oxide particles
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 title claims description 126
- 239000002245 particle Substances 0.000 title claims description 76
- 239000000843 powder Substances 0.000 title claims description 25
- 239000011148 porous material Substances 0.000 claims description 21
- 229910052598 goethite Inorganic materials 0.000 claims description 19
- AEIXRCIKZIZYPM-UHFFFAOYSA-M hydroxy(oxo)iron Chemical compound [O][Fe]O AEIXRCIKZIZYPM-UHFFFAOYSA-M 0.000 claims description 19
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 claims description 19
- 229910052595 hematite Inorganic materials 0.000 claims description 12
- 239000011019 hematite Substances 0.000 claims description 12
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 claims description 12
- 238000006243 chemical reaction Methods 0.000 description 24
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 13
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 12
- 239000000203 mixture Substances 0.000 description 10
- 239000002783 friction material Substances 0.000 description 9
- 239000000243 solution Substances 0.000 description 8
- 239000007789 gas Substances 0.000 description 7
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 7
- 239000011347 resin Substances 0.000 description 7
- 229920005989 resin Polymers 0.000 description 7
- 239000007864 aqueous solution Substances 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 6
- 230000007423 decrease Effects 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 238000001035 drying Methods 0.000 description 4
- 238000000635 electron micrograph Methods 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 238000010298 pulverizing process Methods 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- 239000011246 composite particle Substances 0.000 description 3
- 239000000470 constituent Substances 0.000 description 3
- 239000011790 ferrous sulphate Substances 0.000 description 3
- 235000003891 ferrous sulphate Nutrition 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 229910052791 calcium Inorganic materials 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 230000018044 dehydration Effects 0.000 description 2
- 238000006297 dehydration reaction Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000011812 mixed powder Substances 0.000 description 2
- 239000003607 modifier Substances 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000011164 primary particle Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L sodium carbonate Substances [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 238000004438 BET method Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000002537 cosmetic Substances 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229960002089 ferrous chloride Drugs 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 150000002506 iron compounds Chemical class 0.000 description 1
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical compound Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 description 1
- 229910000358 iron sulfate Inorganic materials 0.000 description 1
- YWXYYJSYQOXTPL-SLPGGIOYSA-N isosorbide mononitrate Chemical compound [O-][N+](=O)O[C@@H]1CO[C@@H]2[C@@H](O)CO[C@@H]21 YWXYYJSYQOXTPL-SLPGGIOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000002459 porosimetry Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 238000001694 spray drying Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
- 229910006540 α-FeOOH Inorganic materials 0.000 description 1
Landscapes
- Compounds Of Iron (AREA)
Description
本発明は、ブレーキパッドの摩擦調整材に用いる酸化鉄に関するものである。 The present invention relates to iron oxide used as a friction adjusting material for brake pads.
ブレーキパッドは繊維状基材、樹脂結合材、摩擦調整材などから構成されている。摩擦調整材としては種々提案されているが、その中の一つとして酸化鉄が知られている。 Brake pads are composed of a fibrous base material, a resin binding material, a friction adjustment material, and the like. Various friction modifiers have been proposed, one of which is iron oxide.
また、ブレーキパッドは耐フェード性が優れていることが求められており、摩擦調整材である酸化鉄にもその機能が求められている。 In addition, brake pads are required to have excellent fade resistance, and iron oxide, which is a friction modifier, is also required to have this function.
フェード現象は、ブレーキの高温化に伴ってディスクパッドの成分である樹脂成分が分解・ガス化し、ディスクローターとの界面にガス層が形成されることによってブレーキの効きが悪化する現象である。これを改善するにはブレーキパッドの気孔率を高めて摩擦材面からガスを逃しやすくすることが有効である。 The fade phenomenon is a phenomenon in which the resin component of the disc pad decomposes and gasifies as the brake temperature increases, forming a gas layer at the interface with the disc rotor, which deteriorates the effectiveness of the brake. In order to improve this problem, it is effective to increase the porosity of the brake pad to make it easier for gas to escape from the friction material surface.
ブレーキパッドの気孔率を向上する方法として、原料混合粉を成型する際に成型圧力を低めにすることが考えられる。しかし、圧力を低くすると、ブレーキパッドの強度や耐摩耗性が低下し、特性が得られなくなるという問題がある。 One possible method for improving the porosity of brake pads is to lower the molding pressure when molding the raw material mixed powder. However, if the pressure is lowered, there is a problem that the strength and wear resistance of the brake pad decreases, making it impossible to obtain the desired characteristics.
ブレーキパッドの特性を損なうことなく、気孔率を高めるためには使用する酸化鉄自体の気孔率を向上する必要がある。すなわち、少なくともかさ密度が低い酸化鉄が求められている。 In order to increase the porosity without impairing the properties of the brake pad, it is necessary to improve the porosity of the iron oxide itself used. That is, iron oxide having at least a low bulk density is required.
従来、酸化鉄を用いた摩擦材が知られている（特許文献１～３）。 Conventionally, friction materials using iron oxide have been known (Patent Documents 1 to 3).
ブレーキパッドの特性を損なうことなく気孔率を高めるために、使用する酸化鉄自体の特性を改善することが求められているが、未だ得られていない。 In order to increase the porosity without impairing the properties of the brake pad, it is required to improve the properties of the iron oxide itself used, but this has not yet been achieved.
特許文献１には、マグネタイトを含有してなる摩擦材組成物が記載されている。マグネタイトの摩擦係数の安定性及び摩擦係数の向上の点で、マグネタイトは多面体及び針状であることが好ましいと記載されている。しかしながら、特許文献１記載の多面体および針状のマグネタイトは、一次粒子の状態であり、高い細孔容積を有するとは言いがたい。 Patent Document 1 describes a friction material composition containing magnetite. It is described that magnetite is preferably polyhedral and acicular in terms of stability and improvement of the friction coefficient of magnetite. However, the polyhedral and acicular magnetite described in Patent Document 1 are in the state of primary particles and cannot be said to have a high pore volume.
特許文献２には、酸化鉄一次粒子と樹脂とを複合化してなる複合体粒子を含有する摩擦材が記載されている。しかしながら、複合体粒子は樹脂との混合物であるためブレーキパッドの気孔率を向上する効果は期待できるものの、酸化鉄複合粒子自体から樹脂のガスが発散され、フェード特性の低下を招いてしまうものと考えられる。 Patent Document 2 describes a friction material containing composite particles formed by combining iron oxide primary particles and a resin. However, since composite particles are a mixture with resin, they can be expected to have the effect of improving the porosity of brake pads, but resin gas is emitted from the iron oxide composite particles themselves, resulting in a decrease in fade characteristics. Conceivable.
特許文献３には、スプレードライ法によるブレーキ摩擦材用酸化鉄粉末が提案されている。しかしながら、記載の細孔容積は１０ｍｍ３／ｇ以上１８０ｍｍ３／ｇ以下であり、ブレーキパッドの気孔率向上に寄与するものと考えられるが、十分な特性を得られないものと考えられる。 Patent Document 3 proposes iron oxide powder for brake friction materials produced by a spray drying method. However, the pore volume described is 10 mm 3 /g or more and 180 mm 3 /g or less, which is considered to contribute to improving the porosity of the brake pad, but it is considered that sufficient characteristics cannot be obtained.
そこで、本発明は、ブレーキパッドの気孔率を高めることが可能な、かさ密度が低い酸化鉄を提供することを目的とする。 Therefore, an object of the present invention is to provide an iron oxide with a low bulk density that can increase the porosity of a brake pad.
本発明者らは、前記技術的課題に鑑み検討を行った結果、ブレーキパッドの気孔率を高めることが可能な、かさ密度が低い酸化鉄を得ることができ、本発明に至った。 As a result of studies conducted in view of the above-mentioned technical problems, the present inventors were able to obtain an iron oxide with a low bulk density that can increase the porosity of a brake pad, leading to the present invention.
前記技術的課題は、次の通りの本発明によって達成できる。 The above technical problem can be achieved by the present invention as follows.
即ち、本発明は、ゲーサイト、マグネタイト及びヘマタイトから構成される酸化鉄粒子粉末であって、ゲーサイトの含有量が２０～９０ｗｔ％であって、かさ密度が０．１～０．３ｇ／ｃｃであることを特徴とする凝集酸化鉄粒子粉末である（本発明１）。 That is, the present invention is an iron oxide particle powder composed of goethite, magnetite, and hematite, the content of goethite is 20 to 90 wt%, and the bulk density is 0.1 to 0.3 g/cc. It is an agglomerated iron oxide particle powder characterized by the following (present invention 1).
また、本発明は、平均粒子径が１μｍ～２０μｍである本発明１に記載の凝集酸化鉄粒子粉末である（本発明２）。 Further, the present invention is the agglomerated iron oxide particle powder according to Invention 1, which has an average particle diameter of 1 μm to 20 μm (Invention 2).
また、本発明は、ＢＥＴ比表面積が１０～５０ｍ２／ｇである本発明１又は２に記載の凝集酸化鉄粒子粉末である（本発明３）。 Further, the present invention is the agglomerated iron oxide particle powder according to Invention 1 or 2, which has a BET specific surface area of 10 to 50 m 2 /g (Invention 3).
また、本発明は、細孔容積が０．８～２．００ｃｃ／ｇである本発明１～３のいずれかに記載の凝集酸化鉄粒子粉末である（本発明４）。 Further, the present invention is an agglomerated iron oxide particle powder according to any one of Inventions 1 to 3, which has a pore volume of 0.8 to 2.00 cc/g (Invention 4).
本発明に係る凝集酸化鉄は、かさ密度が低いので、ブレーキパッドの特性を損なうことなく気孔率を高めることができるので、ブレーキパッド用摩擦材として好適である。 Since the aggregated iron oxide according to the present invention has a low bulk density, it is possible to increase the porosity without impairing the characteristics of the brake pad, and therefore it is suitable as a friction material for a brake pad.
本発明の構成をより詳しく説明すれば次のとおりである。 The configuration of the present invention will be explained in more detail as follows.
まず、本発明に係る凝集酸化鉄粒子粉末について述べる。 First, the agglomerated iron oxide particles according to the present invention will be described.
本発明に係る凝集酸化鉄粉末は、ゲーサイト（α－ＦｅＯＯＨ）、マグネタイト（（ＦｅＯ）ｘ・Ｆｅ２Ｏ３、０＜ｘ≦１）、ヘマタイト（α－Ｆｅ２Ｏ３）の三種類の構成相からなる。 The agglomerated iron oxide powder according to the present invention contains three types of iron oxide powder: goethite (α-FeOOH), magnetite ((FeO)x·Fe 2 O 3 , 0<x≦1), and hematite (α-Fe 2 O 3 ). Consists of constituent phases.
本発明に係る凝集酸化鉄粒子粉末の粒子形状は、針状体と粒状体が凝集結着した形状である。粒状体とは、八面体、六面体、多面体、球状などである。本発明ではゲーサイトの針状粒子、およびマグネタイト、ヘマタイトの粒状粒子を含有した凝集構造をとっている。この凝集構造はゲーサイトの針状粒子が３次元的に絡み合った構造が基本骨格となっており、その基本骨格の中に粒状粒子のマグネタイト、ヘマタイトが入り込むことより、ゲーサイトの針状粒子間の空孔を押し広げる形状を形成させている。本構造を形成することにより、空孔が広がり、かさ密度が低く、大きな細孔容積を有することができる。 The particle shape of the agglomerated iron oxide particles according to the present invention is a shape in which needle-shaped bodies and granular bodies are aggregated and bound. The granular bodies are octahedral, hexahedral, polyhedral, spherical, and the like. The present invention has an agglomerated structure containing acicular particles of goethite and granular particles of magnetite and hematite. The basic framework of this agglomerated structure is a structure in which acicular particles of goethite are intertwined three-dimensionally, and as the granular particles of magnetite and hematite enter into this basic framework, the acicular particles of goethite are intertwined. A shape that expands the pores is formed. By forming this structure, the pores are expanded, the bulk density is low, and the pore volume can be large.
ゲーサイトの針状粒子のみであると、細孔の広がりがなくなり、細孔容積が小さくなってしまう。また、粒状粒子のみであると、比表面積が低くなり、こちらも細孔容積が小さくなってしまう。 If only acicular particles of goethite are used, the pores will not expand and the pore volume will become small. Moreover, if only granular particles are used, the specific surface area becomes low, and the pore volume also becomes small.
また、ゲーサイトは加熱されることにより、組成変化することが知られている。加熱によりＦｅ２Ｏ３へ変化する際に脱水を伴うが、その際に脱水による比表面積の増大を伴う。本発明に係る凝集酸化鉄粒子粉末においても、樹脂中への混練、ブレーキとして加熱環境の中へ粒子が供される。その際に、凝集酸化鉄粒子粉末は水を失い、一部Ｆｅ２Ｏ３構造をとるものと考えられ、比表面積の増大により気孔率（細孔容積）の増大に寄与するものと考えられる。さらに、高温加熱された際には凝集酸化鉄粒子粉末は一部体積の収縮が生じるものと思われる。体積の収縮によりブレーキパッド表面には微細な気孔が生じ、その気孔がガス拡散に寄与するものと考えられる。 Furthermore, it is known that the composition of goethite changes when it is heated. When it changes to Fe 2 O 3 by heating, it accompanies dehydration, and at that time, the specific surface area increases due to the dehydration. In the agglomerated iron oxide particle powder according to the present invention, the particles are also kneaded into a resin and subjected to a heating environment as a brake. At this time, it is thought that the aggregated iron oxide particles lose water and partially take on a Fe 2 O 3 structure, which is thought to contribute to an increase in porosity (pore volume) due to an increase in specific surface area. Furthermore, it is thought that some volume of the agglomerated iron oxide particles shrinks when heated at high temperatures. It is thought that fine pores are generated on the surface of the brake pad due to volumetric contraction, and these pores contribute to gas diffusion.
本発明に係る凝集酸化鉄粒子粉末は、組成的にはゲーサイトが２０～９０％である。ゲーサイトの含有量が２０％未満であると、凝集粒子中の気孔が減少してしまい、ゲーサイトの含有量が９０％を超えると針状構造が密となり、気孔が減少してしまう。好ましくはゲーサイトが２３～８８％、より好ましくはゲーサイトが２５～８５％である。 The composition of the agglomerated iron oxide particles according to the present invention is 20 to 90% goethite. If the goethite content is less than 20%, the pores in the aggregated particles will decrease, and if the goethite content exceeds 90%, the acicular structure will become dense and the pores will decrease. Preferably the content is 23-88% goethite, more preferably 25-85% goethite.
また、本発明に係る凝集酸化鉄粒子粉末はマグネタイトの含有量が１～７５％、ヘマタイトの含有量が５～４０％の範囲であることが好ましい。より好ましくはマグネタイトの含有量が２～７０％、ヘマタイトの含有量が６～３８％、さらにより好ましくはマグネタイトの含有量が３～４５％、ヘマタイトの含有量が７～３５％である。これらの割合は重量％である。 Further, it is preferable that the agglomerated iron oxide particles according to the present invention have a magnetite content of 1 to 75% and a hematite content of 5 to 40%. More preferably, the magnetite content is 2 to 70%, the hematite content is 6 to 38%, and even more preferably the magnetite content is 3 to 45%, and the hematite content is 7 to 35%. These proportions are in weight percent.
本発明に係る凝集酸化鉄粒子粉末は、針状体、粒状体が凝集結着した構造をしている。本発明に係る凝集酸化鉄粒子粉末を構成する粒子の大きさを測定することは難しいが、０．０２～１．５μｍであることが好ましく、より好ましくは０．０５～１．０μｍである。粒子の大きさが前記範囲にあることによって、高い細孔容積を確保することができる。 The agglomerated iron oxide particle powder according to the present invention has a structure in which needle-shaped bodies and granular bodies are aggregated and bound. Although it is difficult to measure the size of the particles constituting the agglomerated iron oxide particles according to the present invention, it is preferably 0.02 to 1.5 μm, more preferably 0.05 to 1.0 μm. By having the particle size within the above range, a high pore volume can be ensured.
本発明に係る凝集粒子酸化鉄粒子粉末の平均粒子径は１μｍ～２０μｍであることが好ましい。１μｍ未満であると樹脂への分散性が悪くなり、２０μｍを超えると、ブレーキの制動時に発生する熱により分解したディスクパッドの成分が、ディスクローター上へ移着する移着層の厚みに対して大きすぎるため、移着層を剥がしてしまい、ブレーキの磨耗量が増大してしまう恐れがある。より好ましい平均粒子径は２～１５μｍである。 The average particle diameter of the agglomerated iron oxide particles according to the present invention is preferably 1 μm to 20 μm. If it is less than 1 μm, the dispersibility into the resin will be poor, and if it exceeds 20 μm, the components of the disc pad decomposed by the heat generated during braking will be difficult to transfer to the thickness of the transfer layer that is transferred onto the disc rotor. If it is too large, the transfer layer may be peeled off and the amount of wear on the brake may increase. A more preferable average particle diameter is 2 to 15 μm.
本発明に係る凝集酸化鉄粒子粉末はＢＥＴ比表面積が１０～５０ｍ２／ｇであることが好ましい。ＢＥＴ比表面積を前記範囲に制御することによって、摩擦材としてガス流通性に優れたものとなる。より好ましいＢＥＴ比表面積は１５～４０ｍ２／ｇである。 The agglomerated iron oxide particles according to the present invention preferably have a BET specific surface area of 10 to 50 m 2 /g. By controlling the BET specific surface area within the above range, it becomes a friction material with excellent gas flowability. A more preferable BET specific surface area is 15 to 40 m 2 /g.
本発明に係る凝集酸化鉄粒子粉末はかさ密度が０．１０～０．３０ｇ／ｃｃであることが好ましい。かさ密度を前記範囲に制御することによって、ブレーキパッドの気孔率を高めることが期待できる。より好ましいかさ密度は０．１２～０．２８ｇ／ｃｃであり、さらにより好ましくは０．１３～０．２７ｇ／ｃｃである。 The aggregated iron oxide particles according to the present invention preferably have a bulk density of 0.10 to 0.30 g/cc. By controlling the bulk density within the above range, it is expected that the porosity of the brake pad will be increased. More preferred bulk density is 0.12 to 0.28 g/cc, even more preferred is 0.13 to 0.27 g/cc.
本発明に係る凝集酸化鉄粒子粉末は細孔容積が０．８～２．０ｇ／ｃｃであることが好ましい。細孔容積が０．８ｇ／ｃｃ未満であると従来酸化鉄と同等以下となり、２．０ｃｃ／ｇを超える場合は凝集粒子の強度低下の点で好ましくない。より好ましい吸油量は０．９～１．８ｇ／ｃｃである。 The agglomerated iron oxide particles according to the present invention preferably have a pore volume of 0.8 to 2.0 g/cc. If the pore volume is less than 0.8 g/cc, it will be equal to or lower than conventional iron oxide, and if it exceeds 2.0 cc/g, it is not preferable in terms of a decrease in the strength of the aggregated particles. A more preferable oil absorption amount is 0.9 to 1.8 g/cc.
次に、本発明に係る凝集酸化鉄粒子粉末の製造法について述べる。 Next, a method for producing agglomerated iron oxide particles according to the present invention will be described.
本発明に係る凝集酸化鉄粒子粉末は、第一鉄塩水溶液とアルカリ水溶液とを反応器に加え、所定の温度、所定のｐＨを維持し、反応溶液に機械的な攪拌を行うとともに、酸化反応を行い、反応終了後、濾過、水洗、乾燥、粉砕を行って得ることができる。 The agglomerated iron oxide particle powder according to the present invention is produced by adding a ferrous salt aqueous solution and an alkaline aqueous solution to a reactor, maintaining a predetermined temperature and a predetermined pH, mechanically stirring the reaction solution, and performing an oxidation reaction. After the reaction is completed, the product can be obtained by performing filtration, washing with water, drying, and pulverization.
本発明の反応において、反応鉄濃度は０．４～２．０ｍｏｌ／Ｌである。０．４ｍｏｌ／Ｌ未満の場合には、目的の形状と粒子径のものを作製できない。２．０ｍｏｌ／ｌより大きい場合には高粘性となり工業的に製造が困難になる。 In the reaction of the present invention, the reaction iron concentration is 0.4 to 2.0 mol/L. If it is less than 0.4 mol/L, particles with the desired shape and particle size cannot be produced. If it is larger than 2.0 mol/l, it becomes highly viscous and difficult to manufacture industrially.
本発明の反応に用いるＦｅ２＋水溶液としては、例えば、硫酸第一鉄や塩化第一鉄などの一般的な鉄化合物を用いることができる。またアルカリ溶液には、水酸化ナトリウム、炭酸ナトリウムなどのアルカリ水溶液を用いることができる。各々の原料は、経済性や反応効率などを考慮して選択すればよい。 As the Fe 2+ aqueous solution used in the reaction of the present invention, for example, common iron compounds such as ferrous sulfate and ferrous chloride can be used. Moreover, an alkaline aqueous solution such as sodium hydroxide or sodium carbonate can be used as the alkaline solution. Each raw material may be selected in consideration of economic efficiency, reaction efficiency, and the like.
本発明の反応において、反応温度は８０～１００℃である。８０℃未満である場合には、凝集構造を持たない酸化鉄が生成し、目的の形状と粒子径のものを作製できない。１００℃を超える場合も目的の凝集酸化鉄粒子を得ることができるが、オートクレーブ等の装置を必要とするため工業的ではない。 In the reaction of the present invention, the reaction temperature is 80 to 100°C. If the temperature is lower than 80°C, iron oxide without an agglomerated structure will be produced, making it impossible to produce the desired shape and particle size. Although it is possible to obtain the desired agglomerated iron oxide particles when the temperature exceeds 100°C, it is not industrially practical because it requires equipment such as an autoclave.
本発明の反応において、反応時のｐＨはｐＨ３．０～５．０である。ｐＨ３．０未満である場合には、未反応の硫酸鉄が溶液中に残存してしまうため工業的に非効率となる。ｐＨ５．０を超える場合には、マグネタイトが主組成となってしまうため目的の組成、凝集構造のものを得ることができない。 In the reaction of the present invention, the pH during the reaction is from 3.0 to 5.0. If the pH is less than 3.0, unreacted iron sulfate will remain in the solution, resulting in industrial inefficiency. If the pH exceeds 5.0, the main composition will be magnetite, making it impossible to obtain the desired composition and agglomerated structure.
アルカリ水溶液の使用量は、第一鉄塩水溶液中のＦｅ２＋に対して１．０～３．０当量が好ましく、より好ましくは１．０～２．５当量の範囲である。１．０当量未満の場合には、未反応の第一鉄塩が存在し、目的のマグネタイト粒子を単一相として得ることができない。３．０当量を越える場合には、反応溶液が高粘性となり工業的に製造が困難になる。 The amount of the alkaline aqueous solution used is preferably 1.0 to 3.0 equivalents, more preferably 1.0 to 2.5 equivalents, based on Fe 2+ in the ferrous salt aqueous solution. When the amount is less than 1.0 equivalent, unreacted ferrous salt is present, and the desired magnetite particles cannot be obtained as a single phase. If the amount exceeds 3.0 equivalents, the reaction solution becomes highly viscous, making industrial production difficult.
本発明において、酸化手段は酸素含有ガス（例えば空気）を液中に通気することにより行う。 In the present invention, the oxidation means is carried out by passing an oxygen-containing gas (for example, air) into the liquid.
反応時に一般に知られているようにＭｎ、Ｚｎ、Ｎｉ、Ｃｕ、Ｔｉ、Ｓｉ、Ａｌ、Ｍｇ、Ｃａから選ばれる１種又は２種以上の元素の塩を添加してもよい。添加量としては凝集酸化鉄粒子粉末に対して０～５．０重量％が好ましい。 During the reaction, salts of one or more elements selected from Mn, Zn, Ni, Cu, Ti, Si, Al, Mg, and Ca may be added as is generally known. The amount added is preferably 0 to 5.0% by weight based on the aggregated iron oxide particles.
凝集酸化鉄粒子にＭｎ、Ｚｎ、Ｎｉ、Ｃｕ、Ｔｉ、Ｓｉ、Ａｌ、Ｍｇ、Ｃａから選ばれる１種又は２種以上の元素を含む化合物で表面処理してもよい。添加量としては凝集酸化鉄粒子粉末に対して０～５．０重量％が好ましい。 The surface of the aggregated iron oxide particles may be treated with a compound containing one or more elements selected from Mn, Zn, Ni, Cu, Ti, Si, Al, Mg, and Ca. The amount added is preferably 0 to 5.0% by weight based on the aggregated iron oxide particles.
反応後は、常法に従って、水洗、乾燥、粉砕を行えばよい。 After the reaction, washing with water, drying, and pulverization may be carried out according to conventional methods.
本発明に係る凝集酸化鉄粒子粉末は、高い細孔容積を有するので、ブレーキパットの摩擦材のほか、触媒担体用、化粧品用、吸着材用などにも用いることができる。 Since the aggregated iron oxide particles according to the present invention have a high pore volume, they can be used not only as friction materials for brake pads but also as catalyst carriers, cosmetics, adsorbents, and the like.
本発明の代表的な実施例は、次の通りである。なお、表１に製造方法、表２に諸特性を示す。 Representative embodiments of the invention are as follows. In addition, Table 1 shows the manufacturing method, and Table 2 shows various properties.
試料の結晶相の含有量は「Ｂｒｕｋｅｒ ＡＸＳ Ｋ．Ｋ」（ブルカー・エイエックスエス（株）製）ＸＲＤ装置と付属のＴＯＰＡＳソフトウェアを用いて測定した。 The crystalline phase content of the sample was measured using a "Bruker AXS K.K" (manufactured by Bruker AXS Co., Ltd.) XRD apparatus and the attached TOPAS software.
試料の粒子形状は、「走査型電子顕微鏡Ｓ－４８００」（（株）日立ハイテクノロジーズ製）により観察した写真から判断した。凝集した酸化鉄粒子粉末の構成粒子形状について、構成する平面から針状、八面体、六面体、多面体又は球状などの形状を観察した写真から判断した。 The particle shape of the sample was determined from a photograph observed using a "scanning electron microscope S-4800" (manufactured by Hitachi High-Technologies Corporation). The shape of the constituent particles of the agglomerated iron oxide particles was determined from photographs of the constituent planes, such as acicular, octahedral, hexahedral, polyhedral, or spherical shapes.
試料の比表面積は、「モノソーブＭＳ－１１」（カンタクロム（株）製）を用いて、ＢＥＴ法により測定した。 The specific surface area of the sample was measured by the BET method using "Monosorb MS-11" (manufactured by Quantachrome Co., Ltd.).
試料の平均粒子径は、「ＬＭＳ－２０００ｅ」（（株）セイシン企業製）を用いて測定した。 The average particle diameter of the sample was measured using "LMS-2000e" (manufactured by Seishin Enterprise Co., Ltd.).
試料の細孔容積は、「ポアマスター６０ＧＴ」（カンタクロム（株）製）を用いて、水銀圧入法により測定した。 The pore volume of the sample was measured by mercury porosimetry using "Poremaster 60GT" (manufactured by Quantachrome Co., Ltd.).
試料のかさ密度はＪＩＳＫ５１０１を参考に測定した。 The bulk density of the sample was measured with reference to JIS K5101.
試料の粉体特性は「パウダテスタ」（ホソカワミクロン（株）製）を用いて測定した。 The powder characteristics of the sample were measured using a "Powder Tester" (manufactured by Hosokawa Micron Co., Ltd.).
実施例１
Ｆｅ２＋ １．２ｍｏｌ／Ｌを含む硫酸第一鉄水溶液を１５Ｌと１８Ｎの水酸化ナトリウム水溶液０．２Ｌとを反応器に加え、９０℃において加熱攪拌する。反応時には毎分２０Ｌの空気を通気させると共に、１８Ｎの水酸化ナトリウム水溶液１．８Ｌを少量ずつ滴下し、ｐＨ４．０に調整し反応を行った。反応終了時の、反応鉄濃度は１．０６ｍｏｌ／ｌであった。反応終了後、濾過、水洗、乾燥、粉砕を行い凝集酸化鉄粒子粉末を得た。
得られた凝集酸化鉄粒子粉末は、図１から明らかなように針状粒子と粒状粒子が凝集した構造を有していた。また、平均粒子径は４．１μｍ、ＢＥＴ比表面積は２２．２ｍ２／ｇであった。
Example 1
15 L of an aqueous ferrous sulfate solution containing 1.2 mol/L of Fe 2+ and 0.2 L of an 18N aqueous sodium hydroxide solution are added to a reactor, and the mixture is heated and stirred at 90°C. During the reaction, 20 L of air was passed per minute, and 1.8 L of an 18N aqueous sodium hydroxide solution was dropped little by little to adjust the pH to 4.0, and the reaction was carried out. At the end of the reaction, the reaction iron concentration was 1.06 mol/l. After the reaction was completed, filtration, washing with water, drying, and pulverization were performed to obtain agglomerated iron oxide particle powder.
As is clear from FIG. 1, the obtained agglomerated iron oxide particles had a structure in which acicular particles and granular particles were aggregated. Further, the average particle diameter was 4.1 μm, and the BET specific surface area was 22.2 m 2 /g.
実施例２～５、比較例１～２
凝集酸化鉄粒子粉末の製造条件を種々変化させた以外は、前記実施例１と同様にして凝集酸化鉄粒子粉末を得た。
Examples 2-5, Comparative Examples 1-2
Agglomerated iron oxide particles were obtained in the same manner as in Example 1, except that the manufacturing conditions for the aggregated iron oxide particles were varied.
比較例３
Ｆｅ２＋ １．２ｍｏｌ／Ｌを含む硫酸第一鉄水溶液を１５Ｌと１８Ｎの水酸化ナトリウム水溶液２．５Ｌとを反応器に加え、９５℃において加熱攪拌する。反応時には毎分２０Ｌの空気を通気させて反応を行った。反応時のｐＨは１０．８であった。また、反応終了時の、反応鉄濃度は１．０６ｍｏｌ／ｌであった。反応終了後、濾過、水洗、乾燥、粉砕を行い酸化鉄粒子粉末を得た。
得られた酸化鉄粒子粉末は、八面体のマグネタイトであった。また、平均粒子径は０．６μｍ、ＢＥＴ比表面積は２．７ｍ２／ｇであった。
Comparative example 3
15 L of an aqueous ferrous sulfate solution containing 1.2 mol/L of Fe 2+ and 2.5 L of an 18N aqueous sodium hydroxide solution are added to a reactor, and the mixture is heated and stirred at 95°C. During the reaction, 20 L/min of air was aerated to carry out the reaction. The pH during the reaction was 10.8. Moreover, the reaction iron concentration at the end of the reaction was 1.06 mol/l. After the reaction was completed, filtration, washing with water, drying, and pulverization were performed to obtain iron oxide particle powder.
The obtained iron oxide particles were octahedral magnetite. Further, the average particle diameter was 0.6 μm, and the BET specific surface area was 2.7 m 2 /g.
比較例４
実施例１により得られた凝集酸化鉄粒子粉末はゲーサイト、ヘマタイト、マグネタイトを含有する凝集粒子である。得られた粒子をＳＥＭ像により観察した際の酸化鉄のそれぞれの粒子径を計測した。
比較例４では、あらかじめ、前記実施例１で得られた凝集酸化鉄粒子粉末と同程度の大きさのゲーサイト、ヘマタイト、マグネタイトを用意し、実施例１で得られた凝集酸化鉄粒子粉末と同等の比率でゲーサイト、ヘマタイト、マグネタイトを混合した。得られた混合粉末の諸特性を表２に示す。
Comparative example 4
The aggregated iron oxide particles obtained in Example 1 are aggregated particles containing goethite, hematite, and magnetite. The particle diameter of each iron oxide was measured when the obtained particles were observed using a SEM image.
In Comparative Example 4, goethite, hematite, and magnetite having the same size as the agglomerated iron oxide particle powder obtained in Example 1 were prepared in advance, and the agglomerated iron oxide particle powder and the agglomerated iron oxide particle powder obtained in Example 1 were prepared in advance. Goethite, hematite, and magnetite were mixed in equal proportions. Table 2 shows various properties of the obtained mixed powder.
表２に示す結果から明らかなように、本発明の実施例で得られた酸化鉄粒子粉末は、ゲーサイト、ヘマタイト、マグネタイトを含有した凝集構造を有しており、ＢＥＴ比表面積に対する粒子径が大きく、且つかさ密度、および全細孔容積が高い値を有しており、ブレーキパッドに使用した際に気孔率を高めることができ、摩擦材面からガスを逃しやすくすることが推察された。 As is clear from the results shown in Table 2, the iron oxide particles obtained in the examples of the present invention have an agglomerated structure containing goethite, hematite, and magnetite, and the particle size relative to the BET specific surface area is It is large, has a high bulk density, and has a high total pore volume, and it is presumed that when used in a brake pad, the porosity can be increased, making it easier for gas to escape from the surface of the friction material.
図２は比較例１で得られた混合物の電子顕微鏡写真である。電子顕微鏡写真より明らかなように、混合しただけでは粒子状に凝集した粉末は形成されていない。 FIG. 2 is an electron micrograph of the mixture obtained in Comparative Example 1. As is clear from the electron micrograph, no agglomerated powder was formed just by mixing.
Claims (4)
The agglomerated iron oxide particle powder according to any one of claims 1 to 3, which has a pore volume of 0.8 to 2.00 cc/g.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019180571A JP7415220B2 (en) | 2019-09-30 | 2019-09-30 | Agglomerated iron oxide particles powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019180571A JP7415220B2 (en) | 2019-09-30 | 2019-09-30 | Agglomerated iron oxide particles powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2021054682A JP2021054682A (en) | 2021-04-08 |
| JP7415220B2 true JP7415220B2 (en) | 2024-01-17 |
Family
ID=75273101
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2019180571A Active JP7415220B2 (en) | 2019-09-30 | 2019-09-30 | Agglomerated iron oxide particles powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP7415220B2 (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002220582A (en) | 2001-01-25 | 2002-08-09 | Toda Kogyo Corp | Filler for friction material and friction material using the same |
| WO2016175284A1 (en) | 2015-04-28 | 2016-11-03 | 戸田工業株式会社 | Friction-material filler |
| WO2017170532A1 (en) | 2016-03-30 | 2017-10-05 | 戸田工業株式会社 | Iron oxide particle powder for friction material |
-
2019
- 2019-09-30 JP JP2019180571A patent/JP7415220B2/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002220582A (en) | 2001-01-25 | 2002-08-09 | Toda Kogyo Corp | Filler for friction material and friction material using the same |
| WO2016175284A1 (en) | 2015-04-28 | 2016-11-03 | 戸田工業株式会社 | Friction-material filler |
| WO2017170532A1 (en) | 2016-03-30 | 2017-10-05 | 戸田工業株式会社 | Iron oxide particle powder for friction material |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2021054682A (en) | 2021-04-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107694607B (en) | Low CO2Core-shell catalyst for preparing olefin by selective CO hydrogenation and preparation method thereof | |
| US10106464B2 (en) | Porous titanate compound particles and method for producing same | |
| JP5760599B2 (en) | Magnetic iron oxide particle powder | |
| JP4288452B2 (en) | Method for producing Mg-Al hydrotalcite-type particle powder, chlorine-containing resin stabilizer and chlorine-containing resin composition | |
| JP3910495B2 (en) | Basic magnesium carbonate and method for producing the same, and composition or structure containing the basic magnesium carbonate | |
| GB2063845A (en) | Producing magnetic powder | |
| JP6959583B2 (en) | Iron oxide particle powder for friction materials | |
| JP6487055B2 (en) | Porous titanate compound particles and method for producing the same | |
| JP4338470B2 (en) | Hydrotalcite particles and method for producing the same | |
| JP6359425B2 (en) | Porous aluminum nitride particles | |
| JP7415220B2 (en) | Agglomerated iron oxide particles powder | |
| Kou et al. | Highly efficient and recyclable catalyst: porous Fe3O4–Au magnetic nanocomposites with tailored synthesis | |
| Umegaki et al. | Fabrication of hollow spheres of Co3O4 for catalytic oxidation of carbon monoxide | |
| TW200846075A (en) | Oxychlorination catalyst and method for preparing the same | |
| Tajizadegan et al. | Influence of different alumina precursors on structural properties and morphology of ZnO‐Al2O3 nanocomposite powder | |
| JP7454425B2 (en) | Method for producing cobalt ferrite particles and cobalt ferrite particles produced thereby | |
| JP6958352B2 (en) | Filler for friction material | |
| CN110711553A (en) | Hydrotalcite-pseudo-boehmite composite film and preparation method and application thereof | |
| JPS5919163B2 (en) | Method for producing magnetic metal powder | |
| KR102473107B1 (en) | Superparamagnetic mesoporous Ni-SiO2 microparticles and the preparing method thereof | |
| JP2018165221A (en) | Method for producing boehmite | |
| JP2017171547A (en) | Novel hydrotalcite particle having hierarchical structure | |
| JP4729213B2 (en) | Li-Al layered double hydroxide particle powder and method for producing the same | |
| RU2602129C1 (en) | Method of producing metal-modified filler for rubber | |
| CN108878092B (en) | Nickel-based soft magnetic sheet and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20220915 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20230628 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20230704 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20231129 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20231212 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 7415220 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |