JP2003105326A - Raw material for cerium polishing material and method for analyzing raw material for cerium polishing material - Google Patents
Raw material for cerium polishing material and method for analyzing raw material for cerium polishing materialInfo
- Publication number
- JP2003105326A JP2003105326A JP2001302406A JP2001302406A JP2003105326A JP 2003105326 A JP2003105326 A JP 2003105326A JP 2001302406 A JP2001302406 A JP 2001302406A JP 2001302406 A JP2001302406 A JP 2001302406A JP 2003105326 A JP2003105326 A JP 2003105326A
- Authority
- JP
- Japan
- Prior art keywords
- raw material
- cerium
- abrasive
- rare earth
- based abrasive
- 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.)
- Granted
Links
Landscapes
- Manufacturing Of Magnetic Record Carriers (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、セリウム系研摩材
原料及びセリウム系研摩材原料の分析方法に関する。詳
しくは研摩材としたときに傷の原因となる不純物粒子の
少ないセリウム系研摩材原料、及び、そのようなセリウ
ム系研摩材原料であるか否かを判断することのできる分
析方法に関する。TECHNICAL FIELD The present invention relates to a cerium-based abrasive raw material and a method for analyzing a cerium-based abrasive raw material. More specifically, the present invention relates to a cerium-based abrasive material raw material that has few impurity particles that cause scratches when used as an abrasive, and an analysis method capable of determining whether or not such a cerium-based abrasive material raw material.
【０００２】[0002]
【従来の技術】セリウム系研摩材は、種々のガラス材料
の研摩に用いられており、特に近年では、ハードディス
ク等の磁気記録媒体用ガラス、液晶ディスプレイ（ＬＣ
Ｄ）のガラス基板といった電気・電子機器で用いられて
いるガラス材料の研摩にも用いられており、その応用分
野が広がっている。2. Description of the Related Art Cerium-based abrasives are used for polishing various glass materials. In recent years, in particular, glass for magnetic recording media such as hard disks and liquid crystal displays (LC
It is also used for polishing glass materials used in electric / electronic devices such as the glass substrate of D), and its application fields are expanding.
【０００３】このセリウム系研摩材は、主成分である酸
化セリウム（ＣｅＯ２）粒子と、他の希土類金属酸化物
粒子とからなる研摩材粒子よりなる。また、セリウム系
研摩材の製造方法としては、まず、原料を粉砕した後、
フッ素成分を添加するフッ化処理、異常粒成長の原因と
なる原料中のアルカリ金属を除去する鉱酸処理といった
化学処理（湿式処理）を施す。そして、湿式処理後の原
料を、濾過、乾燥後高温加熱して焙焼することにより原
料粒子同士を焼結し、これを再度粉砕して分級すること
で所望の粒径、粒度分布を有する研摩材が製造される。This cerium-based abrasive comprises abrasive particles composed of cerium oxide (CeO 2 ) particles as the main component and other rare earth metal oxide particles. In addition, as a method for producing a cerium-based abrasive, first, after crushing the raw material,
A chemical treatment (wet treatment) such as a fluorination treatment for adding a fluorine component and a mineral acid treatment for removing an alkali metal in a raw material that causes abnormal grain growth is performed. Then, the raw material after the wet treatment is filtered, dried, and then heated at a high temperature to be roasted to sinter the raw material particles, and the raw material particles are pulverized and classified again to obtain an abrasive having a desired particle size and particle size distribution. The material is manufactured.
【０００４】ここで、セリウム系研摩材の原料として
は、従来は、バストネサイトと呼ばれる希土鉱石を選鉱
したバストネサイト精鉱という天然原料を使用すること
が多かったが、最近ではバストネサイト鉱や比較的安価
な中国産複雑鉱より得られる希土類化合物を焙焼し、そ
の一部又は大部分を酸化希土とする原料が用いられるよ
うになってきている。この酸化希土含有原料は、鉱石を
溶解し化学処理して希土類金属濃度を高めた炭酸希土を
主成分とする希土類化合物を５００℃以上の温度で焙焼
することで、炭酸希土から酸化希土へと変化させるもの
であり、焙焼時間等の条件を調整することで酸化希土含
有量を調節している。Here, as a raw material for cerium-based abrasives, conventionally, a natural raw material called bastnasite concentrate, which is a rare earth ore called bastnasite, was often used, but recently, bastnasite is used. BACKGROUND ART Raw materials obtained by roasting rare earth compounds obtained from site ore and relatively inexpensive Chinese complex ores and using a part or most of them as rare earth oxides have come to be used. This rare earth oxide-containing raw material is oxidized from rare earth carbonate by roasting at a temperature of 500 ° C. or higher by melting an ore and chemically treating the rare earth compound whose main component is rare earth carbonate whose concentration of rare earth metal is increased. The content of rare earth oxide is adjusted by adjusting the conditions such as roasting time.
【０００５】[0005]
【発明が解決しようとする課題】ところで、セリウム系
研摩材に限らず研摩材全般には研摩面に傷を生じさせる
ことなく高精度の研摩面を形成することができることが
求められる。そして、従来のセリウム系研摩材において
はその製造工程において、研摩材粒子の粒度分布、粒径
の調整や、粗大な研摩粒子の除去等を行い研摩傷の発生
することないセリウム系研摩材を製造しようとする試み
が多くなされている。By the way, not only cerium-based abrasives but also abrasives in general are required to be able to form a highly accurate polished surface without causing scratches on the polished surface. In the manufacturing process of conventional cerium-based abrasives, the cerium-based abrasives that do not cause polishing scratches are manufactured by adjusting the particle size distribution of abrasive particles, adjusting the particle size, and removing coarse abrasive particles. Many attempts have been made to try.
【０００６】これに対して、いかなる原料を適用するか
も研摩材の特性に大きな影響を与え得るものと考えられ
る。しかし、これまでの原料に関する検討は、取り扱い
性、コスト、研摩材の生産性等についてなされることが
多いが、研摩材としたときの研摩特性について考慮した
原料を検討された例は少ない。また、調整された原料に
ついての評価法についても、その成分分析等は通常なさ
れるが研摩材の傷発生の可能性のみを考慮したものは少
ない。On the other hand, it is considered that which raw material is used can greatly affect the characteristics of the abrasive. However, although many studies on raw materials have been conducted so far on the handling property, cost, productivity of abrasives, etc., there are few examples of studies on raw materials considering the polishing characteristics of the abrasives. In addition, regarding the evaluation method for the adjusted raw material, its component analysis and the like are usually performed, but few consider only the possibility of scratches on the abrasive.
【０００７】近年、ハードディスク等の記録媒体の高密
度化、ＬＣＤ等で使用される基板の高精度化・精密化に
伴い、そのガラス材料の研摩に使用される研摩材にもこ
れまで以上に高精度の研摩が可能なものが要求されてい
る。そして、このような用途に適用されるセリウム系研
摩材については、その製造工程の管理、改良のみでは自
ずと限界が生じると考えられ、原料段階からの改善が求
められると考えられる。In recent years, with the increasing density of recording media such as hard disks and the increasing precision and accuracy of substrates used in LCDs and the like, the abrasives used for polishing the glass materials have become higher than ever. There is a demand for a material that can be precisely ground. With regard to the cerium-based abrasive applied to such applications, it is considered that there will be a limit naturally only by controlling and improving the manufacturing process, and it is considered that improvement from the raw material stage is required.
【０００８】本発明は、以上のような背景の下になされ
たものであり、セリウム系研摩材に適用される原料につ
いて、研摩材とした際に傷の発生のないものを提供する
ことを目的とする。また、そのような研摩材原料を判別
することのできる分析方法をについても明らかとするこ
とを目的とする。The present invention has been made under the above background, and an object thereof is to provide a raw material applied to a cerium-based abrasive, which does not cause scratches when the abrasive is used. And Moreover, it aims at clarifying the analysis method which can discriminate such an abrasive raw material.
【０００９】[0009]
【課題を解決するための手段】上述したように、研摩材
原料の研摩特性向上の手段としては、研摩材粒子の粒度
分布、粒径の調整、粗大な研摩粒子の除去といったもの
がある。これに対し本発明者等は、セリウム系研摩材に
よる傷の発生を左右する要因として、研摩材粒子径の分
布状態、粗大な研摩粒子の存在に加えて、被研摩材より
も硬度の高い粒子の存在を見出した。そして、本発明者
等によれば、この硬質粒子による影響は、その粒径によ
らず生じうるものであり、微粒のものであっても傷の要
因となる。As described above, as means for improving the polishing characteristics of the abrasive raw material, there are means such as particle size distribution of abrasive particles, adjustment of particle size, and removal of coarse abrasive particles. On the other hand, the present inventors, as factors that affect the occurrence of scratches by the cerium-based abrasive, in addition to the distribution state of the abrasive particle size, the presence of coarse abrasive particles, particles having a hardness higher than the abrasive Found the existence of. According to the present inventors, the influence of the hard particles can occur regardless of the particle size, and even fine particles cause scratches.
【００１０】そこで本発明者等は、この硬質粒子につい
て、その発生要因、組成に関して検討を行った結果、こ
のような硬質粒子は研摩材原料の製造工程において混入
するものであり、特に、希土類化合物を乾燥、焙焼する
際の乾燥炉、焙焼炉、焙焼皿等の構成材料が粉化して混
入すると考察した。また、その組成については明らかで
はないが、焙焼炉の構成材料である耐火材に含まれるケ
イ素成分、アルミニウム成分、ジルコニウム成分又はこ
れらが焙焼時の加熱により変化したものよりなることを
見出した。そして、本発明者等のより詳細な検討から、
この硬質粒子は、酸化希土及び炭酸希土を可溶な溶液で
ある過塩素酸水溶液及び過酸化水素水溶液中においても
溶解することのなく存在し得るものであることが確認さ
れた。The inventors of the present invention have studied the factors causing the hard particles and the composition of the hard particles. As a result, the hard particles are mixed in the manufacturing process of the abrasive raw material. It was considered that the constituent materials such as a drying oven, a roasting oven, and a roasting dish for drying and roasting are mixed into powder. Further, although its composition is not clear, it was found that the refractory material that is a constituent material of the roasting furnace is composed of a silicon component, an aluminum component, a zirconium component, or those changed by heating during roasting. . And from a more detailed study by the present inventors,
It was confirmed that the hard particles can exist without being dissolved even in a perchloric acid aqueous solution and a hydrogen peroxide aqueous solution which are soluble solutions of rare earth oxide and rare earth carbonate.
【００１１】かかる検討結果から、本発明者等は研摩傷
のない高精度の研摩面を形成するセリウム系研摩材の原
料としては、上記した硬質粒子を含まないものが適当で
あるとし、その含有量との関係を鋭意検討し本発明に想
到した。From the results of the above examination, the inventors of the present invention have determined that a material containing no hard particles as described above is suitable as a raw material of a cerium-based abrasive for forming a highly accurate polished surface without abrasive scratches. The present invention has been devised by intensively studying the relationship with the amount.
【００１２】即ち、本発明は、希土類化合物を焙焼する
ことにより得られる酸化希土を含んでなるセリウム系研
摩材原料において、ケイ素、アルミニウム、ジルコニウ
ムの少なくともいずれか一の元素を含み、且つ過塩素酸
水溶液及び過酸化水素水溶液に対して溶解性を有しない
粒子状物質を含有し、前記粒子状物質の含有量は重量比
で２００ｐｐｍ以下であることを特徴とするセリウム系
研摩材原料である。That is, the present invention relates to a cerium-based abrasive material raw material containing rare earth oxide obtained by roasting a rare earth compound, containing at least one element of silicon, aluminum and zirconium, and A cerium-based abrasive material raw material containing a particulate matter that is not soluble in a chloric acid aqueous solution and a hydrogen peroxide aqueous solution, and the content of the particulate matter is 200 ppm or less by weight ratio. .
【００１３】本発明において、「ケイ素、アルミニウ
ム、ジルコニウムの少なくともいずれか一の元素を含
み、且つ過塩素酸水溶液及び過酸化水素水溶液に対して
溶解性を有しない粒子状物質」としたのは、本発明者等
の検討結果に基づき研摩傷の原因となる硬質粒子を可能
な限り特定するためである。即ち、希土類化合物を焙焼
することで製造される研摩材原料には、ケイ素、アルミ
ニウム、ジルコニウム等の元素が含有されているが、傷
の原因となるのはこれらの元素を含む粒子状の物質であ
って硬質化したものであることを明確とすると共に、ケ
イ素、アルミニウム、ジルコニウムの元素を含むもので
あっても過塩素酸水溶液及び過酸化水素水溶液に対して
溶解性を有するものについては研摩傷の原因となること
はないことから、このような溶解性のある物質を排除す
るものである。In the present invention, "particulate material containing at least one element of silicon, aluminum and zirconium and having no solubility in an aqueous solution of perchloric acid and an aqueous solution of hydrogen peroxide" means This is because the hard particles that cause the abrasion scratches are specified as much as possible based on the results of the study by the present inventors. That is, the abrasive raw material produced by roasting a rare earth compound contains elements such as silicon, aluminum and zirconium, but the cause of scratches is a particulate substance containing these elements. And it is clarified that it is hardened, and even if it contains elements of silicon, aluminum, and zirconium, it has a solubility in an aqueous solution of perchloric acid and an aqueous solution of hydrogen peroxide. Since it does not cause scratches, it eliminates such soluble substances.
【００１４】一方、この硬質粒子の含有量について２０
０ｐｐｍ以下としたのは、研摩材とした際の研摩速度と
傷発生の度合いとを考慮し、通常適用される研摩速度の
範囲内で傷発生のおそれのない硬質粒子の量を規定する
ものである。つまり、研摩傷の発生は研摩速度によって
も影響され、研摩速度が高い場合には、研摩材中に硬質
粒子が多少存在し、それによる傷が発生してもその傷は
高速研摩により短時間で除去される。しかし、現実に
は、このような現象を生じさせる程の高速研摩は不可能
であり、工業的に十分且つ達成可能な研摩速度（０．０
１〜０．５μｍ／ｍｉｎ）において傷発生のない原料と
しては、硬質粒子の含有量を２００ｐｐｍ以下とする必
要があるとの検討結果によるものである。On the other hand, the content of the hard particles is 20
The amount of 0 ppm or less is intended to define the amount of hard particles that are not likely to cause scratches within the range of the usually applied polishing speed, in consideration of the polishing speed and the degree of scratches when used as an abrasive. is there. In other words, the occurrence of polishing scratches is also affected by the polishing speed.When the polishing speed is high, some hard particles are present in the polishing material, and even if scratches are generated, the scratches will be produced in a short time by high-speed polishing. To be removed. However, in reality, high-speed polishing that causes such a phenomenon is impossible, and the polishing speed (0.0
It is based on the examination result that the content of hard particles needs to be 200 ppm or less as a raw material having no scratches at 1 to 0.5 μm / min).
【００１５】このように、本発明に係るセリウム系研摩
材原料は、研摩傷の要因となる硬質粒子の含有量が低減
されており、これにより、傷の発生のないセリウム系研
摩材を製造することができる。そして、このセリウム系
研摩材は研摩傷発生の抑制の他、表面粗さに優れた高精
度の研摩面を形成することができる。As described above, the cerium-based abrasive material raw material according to the present invention has a reduced content of hard particles that cause polishing scratches, thereby producing a scratch-free cerium-based abrasive material. be able to. The cerium-based abrasive can suppress the occurrence of polishing scratches and form a highly accurate polished surface having excellent surface roughness.
【００１６】ここで、本発明に係るセリウム系研摩材原
料は、上述した希土類化合物の乾燥、焙焼時において焙
焼炉等の構成材料が混入して発生する硬質粒子を排した
ものである。従って、本発明に係るセリウム系研摩材原
料は、このような焙焼炉等の構成材料の混入を抑制する
ことにより製造可能である。ここで、本発明の対象とな
るセリウム系研摩材原料は、通常、原材料となるバスト
ネサイト鉱、中国産複雑鉱等の鉱石を塩酸等で溶解した
ものを炭酸塩で沈殿させ、ろ過、洗浄を行なった希土類
化合物（炭酸希土）を乾燥、焙焼することで製造され
る。そして、本発明ではこの工程において以下の改良を
行なうことで硬質粒子を排除することができる。Here, the cerium-based abrasive material raw material according to the present invention is one in which hard particles generated by mixing of constituent materials such as a roasting furnace during the drying and roasting of the above-mentioned rare earth compound are eliminated. Therefore, the cerium-based abrasive material raw material according to the present invention can be manufactured by suppressing the mixing of the constituent materials of such a roasting furnace. Here, the cerium-based abrasive raw material to be the subject of the present invention is usually a raw material such as bastnasite ore or a complex ore produced in China dissolved with hydrochloric acid or the like, precipitated with carbonate, filtered, and washed. It is produced by drying and roasting the rare earth compound (rare earth carbonate) which has been subjected to. In the present invention, hard particles can be eliminated by making the following improvements in this step.
【００１７】まず、炭酸塩で沈殿させた希土類化合物の
洗浄においてフッ素濃度が十分低減されるまで洗浄を行
なうことが必要である。これは、バストネサイト等の原
材料に由来するフッ素成分が残留した状態で原材料を乾
燥、焙焼すると、このフッ素成分がフッ化水素として揮
発し乾燥炉、焙焼炉の構成材料を侵食し、硬質粒子混入
の要因となることを考慮したものである。そして、この
洗浄工程は、フッ素濃度が原材料に対して０．１〜０．
０１重量％となるまで洗浄を行なうことが好ましい。First, it is necessary to wash the rare earth compound precipitated by the carbonate until the fluorine concentration is sufficiently reduced. This is because when the raw material is dried and roasted with the fluorine component derived from the raw material such as bastnasite remaining, the fluorine component volatilizes as hydrogen fluoride and erodes the constituent materials of the drying furnace and the roasting furnace, This is because it is a factor of mixing hard particles. In this cleaning step, the fluorine concentration is 0.1 to 0.
It is preferable to perform washing until it reaches 01% by weight.
【００１８】また、洗浄後の乾燥、焙焼工程について
は、乾燥工程を１００〜１５０℃の範囲で行なうのが好
ましい。この温度範囲においては、希土類化合物中のフ
ッ素成分がフッ化水素に変化し難く、乾燥工程における
炉の侵食を抑制することができるからである。更に、焙
焼工程においては焙焼温度を４００℃〜８００℃とする
のが好ましい。４００℃以上とするのは炭酸希土を酸化
希土に酸化させるためであり、８００℃以下とするのは
希土類化合物中のフッ素成分のフッ化水素への変化を抑
制するためである。また、この焙焼工程においては焙焼
炉の形式を選択することで硬質粒子の混入を抑制でき
る。即ち、ロータリーキルンのような連続式の回転炉
は、バッチ式の静置炉に比べて炉体に対する温度変化も
小さいことから熱衝撃も比較的小さいことから、炉体の
粉化、硬質粒子の混入が抑制されるのである。As for the drying and roasting steps after washing, it is preferable to carry out the drying step in the range of 100 to 150 ° C. This is because in this temperature range, the fluorine component in the rare earth compound is unlikely to change to hydrogen fluoride, and erosion of the furnace in the drying step can be suppressed. Further, in the roasting step, the roasting temperature is preferably 400 ° C to 800 ° C. The temperature of 400 ° C. or higher is for oxidizing rare earth carbonate into rare earth oxide, and the temperature of 800 ° C. or lower is for suppressing the change of the fluorine component in the rare earth compound to hydrogen fluoride. In addition, in this roasting step, mixing of hard particles can be suppressed by selecting the type of roasting furnace. That is, since a continuous rotary furnace such as a rotary kiln has a smaller temperature change with respect to the furnace body as compared with a batch-type stationary furnace and therefore has a relatively small thermal shock, powdering of the furnace body and mixing of hard particles are not caused. It is suppressed.
【００１９】尚、研摩材原料への硬質粒子の混入をより
確実に防止するためには、乾燥炉、焙焼炉、焙焼皿等を
侵食、崩壊し難い硬質の耐火材料で製造し、これらによ
り希土類化合物を乾燥、焙焼するのが好ましい。例え
ば、炉体の研摩材原料と接触する部分をステンレス鋼の
ような耐熱性金属材料で製造することや、アルミナ含有
量が高く耐火性の高い材料を適用することにより炉体の
侵食、崩壊を抑制することができる。In order to more reliably prevent hard particles from mixing into the abrasive raw material, a drying furnace, a roasting furnace, a roasting dish, etc. are made of a hard refractory material that is resistant to erosion and collapse. Therefore, it is preferable to dry and roast the rare earth compound. For example, the part of the furnace body that comes into contact with the abrasive raw material is made of a heat-resistant metal material such as stainless steel, or the material that has a high alumina content and high fire resistance is used to prevent erosion and collapse of the furnace body. Can be suppressed.
【００２０】ところで、本発明者等が見出したセリウム
系研摩材原料に含まれる硬質粒子は、過塩素酸水溶液及
び過酸化水素水溶液に対して不溶性という特性を有す
る。そこで、本発明者等はこの特性を利用して、任意の
工程で製造された研摩材原料について、当該研摩材原料
を研摩材としたときに傷発生の可能性の有無を評価する
方法を見出した。By the way, the hard particles contained in the cerium-based abrasive raw material found by the present inventors have the property of being insoluble in an aqueous solution of perchloric acid and an aqueous solution of hydrogen peroxide. Therefore, the present inventors have found a method of utilizing this characteristic to evaluate whether or not there is a possibility of scratch generation when the abrasive raw material produced in any process is used as the abrasive. It was
【００２１】この分析方法は、希土類化合物を焙焼する
ことにより得られる酸化希土を含んでなるセリウム系研
摩材原料の分析方法であって、下記工程よりなるもので
ある。This analysis method is a method for analyzing a cerium-based abrasive material raw material containing rare earth oxide obtained by roasting a rare earth compound, and includes the following steps.
【００２２】（ａ）焙焼後のセリウム系研摩材原料から
サンプルを採取し秤量する工程。
（ｂ）前記サンプルに過塩素酸水溶液及び過酸化水素水
溶液を添加し、添加後の溶液を加温する工程。
（ｃ）加温後の溶液をろ過する工程。
（ｄ）濾過後の残渣の重量を測定し、前記試料の重量と
残渣の重量との比を算出する工程。(A) A step of collecting and weighing a sample from the cerium-based abrasive raw material after roasting. (B) A step of adding an aqueous solution of perchloric acid and an aqueous solution of hydrogen peroxide to the sample and heating the solution after the addition. (C) A step of filtering the solution after heating. (D) A step of measuring the weight of the residue after filtration and calculating the ratio of the weight of the sample to the weight of the residue.
【００２３】この分析方法は、検査目的となる研摩材原
料を任意量サンプリングして、過塩素酸水溶液及び過酸
化水素水溶液と接触させることにより、硬質粒子を抽出
し、その研摩材原料中の含有量を定量化する方法であ
る。In this analysis method, an arbitrary amount of an abrasive raw material to be inspected is sampled and brought into contact with an aqueous perchloric acid solution and an aqueous hydrogen peroxide solution to extract hard particles, and the hard particles are contained in the abrasive raw material. It is a method of quantifying the amount.
【００２４】以下、この分析方法について詳細に説明す
る。まず、所定の工程を経て製造されたセリウム系研摩
材原料から任意量をサンプルとして採取・秤量する
（（ａ）工程）。ここで、この際のサンプリング量とし
ては、硬質粒子量が微量であることと分析の効率と併せ
て考慮すれば、１０〜５００ｇ程度採取するのが適当で
ある。The analysis method will be described in detail below. First, an arbitrary amount is sampled and weighed from a cerium-based abrasive raw material manufactured through a predetermined process (process (a)). Here, as the sampling amount at this time, it is appropriate to collect about 10 to 500 g in consideration of the small amount of hard particles and the analysis efficiency.
【００２５】次に、秤量した研摩材原料に過塩素酸水溶
液及び過酸化水素水溶液を添加し、更に加温する。これ
により研摩材原料中の酸化希土、炭酸希土等の主要成分
は溶解し、残滓として硬質粒子が残留する（（ｂ）工
程）。このとき、研摩材原料（炭酸希土、酸化希土）を
溶解させるのは主に過塩素酸水溶液であり、過酸化水素
水溶液は溶解補助剤、特に、研摩材原料中のセリウムを
溶解性の高い４価の状態に保持する役割を有する。そし
て、これら溶液の濃度は、過塩素酸水溶液については５
〜２０重量％程度のものを用いるのが好ましい。研摩材
原料を効率的に溶解させると共に試薬の無駄を考慮した
ものである。また、過酸化水素水溶液については、溶解
補助剤としての役割から、０．１〜５重量％の物を用い
るのが好ましい。尚、この工程の過塩素酸水溶液及び過
酸化水素水溶液の添加の順序は特に限定されるものでは
なく、いずれを先に添加しても差し支えない。一方、こ
の工程において、溶液混合後に加温を行なうのは研摩材
原料の溶解を促進するためであるが、この温度について
は、８０℃以上で混合溶液の沸点近傍（９０℃）とする
のが好ましい。Next, an aqueous solution of perchloric acid and an aqueous solution of hydrogen peroxide are added to the weighed abrasive raw material and further heated. As a result, main components such as rare earth oxide and rare earth carbonate in the abrasive raw material are dissolved, and hard particles remain as a residue (step (b)). At this time, the abrasive raw material (rare earth carbonate, rare earth oxide) is mainly dissolved in the aqueous solution of perchloric acid, and the aqueous hydrogen peroxide solution is a solubilizing agent, in particular, cerium in the raw material of the abrasive is soluble. It has a role of maintaining a high tetravalent state. And, the concentration of these solutions is 5 for an aqueous solution of perchloric acid.
It is preferable to use the one of about 20% by weight. This is because the abrasive raw material is efficiently dissolved and the waste of the reagent is taken into consideration. Further, with respect to the hydrogen peroxide aqueous solution, it is preferable to use 0.1 to 5% by weight from the viewpoint of a role as a dissolution aid. The order of adding the aqueous solution of perchloric acid and the aqueous solution of hydrogen peroxide in this step is not particularly limited, and any of them may be added first. On the other hand, in this step, heating is performed after mixing the solutions in order to accelerate the dissolution of the abrasive raw material, but at this temperature, the boiling point of the mixed solution should be around 80 ° C. or higher (90 ° C.). preferable.
【００２６】そして、研摩材原料を溶解させた溶液をろ
過し、硬質粒子を回収する（（ｂ）工程）。このろ過工
程において適用するろ過材は、孔径０．３〜５μｍのフ
ィルター（篩）を用いるのが好ましい。Then, the solution in which the abrasive raw material is dissolved is filtered to collect hard particles (step (b)). It is preferable to use a filter (sifter) having a pore size of 0.3 to 5 μm as the filtering material applied in this filtering step.
【００２７】以上の工程を経ることにより回収される硬
質粒子については、その重量を測定し、サンプルの重量
との比を算出することでセリウム系研摩材原料中の含有
量を規定することができる（（ｄ）工程）。そして、こ
のようにして測定される硬質粒子含有量からセリウム系
研摩材原料としての適性が判断されることとなる。With respect to the hard particles recovered through the above steps, the content thereof in the cerium-based abrasive raw material can be specified by measuring the weight and calculating the ratio with the weight of the sample. (Step (d)). Then, the suitability as a cerium-based abrasive material raw material is judged from the hard particle content thus measured.
【００２８】以上説明したセリウム系研摩材原料の分析
方法は、複数の工程を有するものの、各工程自体は必ず
しも困難な方法ではなく、全体としてみても簡便な分析
方法である。従って、この分析方法によれば、任意の方
法により製造されたセリウム系研摩材原料の品質（研摩
傷の原因物質の有無）を簡単に評価することができる。Although the cerium-based abrasive raw material analysis method described above has a plurality of steps, each step itself is not necessarily a difficult method, and is a simple analysis method as a whole. Therefore, according to this analysis method, it is possible to easily evaluate the quality of the cerium-based abrasive raw material produced by an arbitrary method (presence or absence of a substance causing abrasive scratches).
【００２９】[0029]
【発明の実施の形態】以下、本発明の好適な実施形態を
説明する。BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below.
【００３０】ここでは、希土類鉱石を原材料とし、これ
を溶解、炭酸希土としたものをフッ素含有量が０．１重
量％未満となるまで洗浄した原材料を乾燥後、アルミナ
含有量が９９重量％の炉材を用いたロータリーキルンに
て６００℃で焙焼することで研摩材原料を６種類製造し
た。また、これに対する比較例として、同様の原料を溶
解、炭酸塩とし、フッ素含有量が０．５重量％となるま
で洗浄し、乾燥後に静置炉で６００℃で焙焼して研摩材
原料を３種類製造した。Here, a rare earth ore is used as a raw material, and this is dissolved and made into rare earth carbonate and washed until the fluorine content is less than 0.1% by weight. After drying the raw material, the alumina content is 99% by weight. Six types of abrasive raw materials were manufactured by roasting at 600 ° C. in a rotary kiln using the furnace material of No. 2. In addition, as a comparative example to this, the same raw material was dissolved, carbonated, washed until the fluorine content became 0.5% by weight, dried and then roasted at 600 ° C. in a stationary furnace to give 3 parts of an abrasive raw material. Type manufactured.
【００３１】次に、これらの研摩材原料を図１に示す工
程にて硬質粒子の含有量を測定した。図１において、各
研摩材原料を５０ｇ採取、秤量してサンプルとし、この
サンプルに水１０００ｍｌ添加した後、６０重量％の過
塩素酸水溶液３００ｍｌと、３０重量％の過酸化水素水
溶液２０ｍｌとを添加し、この混合溶液を沸騰させて５
分間保持した。加温後の溶液を徐冷後、孔径０．４４μ
ｍのフィルターに通過させてろ過し、メッシュ上の残渣
を回収し、洗浄、１００℃で乾燥しその重量を測定し
た。そして、この残渣（硬質粒子）重量から各原料中の
硬質粒子含有量を算出した。Next, the content of hard particles of these abrasive raw materials was measured in the process shown in FIG. In FIG. 1, 50 g of each abrasive raw material was sampled and weighed to make a sample. After adding 1000 ml of water to this sample, 300 ml of 60 wt% perchloric acid aqueous solution and 20 ml of 30 wt% hydrogen peroxide aqueous solution were added. Then, boil this mixed solution to 5
Hold for minutes. The solution after heating is gradually cooled and then the pore size is 0.44μ.
The residue on the mesh was collected, washed, dried at 100 ° C. and weighed. Then, the content of hard particles in each raw material was calculated from the weight of the residue (hard particles).
【００３２】次に、これらの原料を用いてセリウム系研
摩材を製造した。研摩材用原料３ｋｇと純水３ｌとを直
径５ｍｍの鋼製の粉砕媒体が充填された湿式ボールミル
（容量５ｌ）にて６時間粉砕し、平均粒径（マイクロト
ラック法Ｄ５０（累積５０％粒径））１μｍの粉体から
なるスラリーとした。その後、最終状態の研摩材中のフ
ッ素濃度が６％となるようにすべく、粉砕スラリーに濃
度１ｍｏｌ／ｌのフッ化アンモニウム溶液を添加した後
に、純水で洗浄後濾過してケーキを得た。次に、このケ
ーキを乾燥後、９００℃で３時間焙焼し、再度粉砕した
後分級してセリウム系研摩材とした。Next, a cerium-based abrasive was manufactured using these raw materials. 3 kg of the abrasive raw material and 3 liters of pure water were pulverized for 6 hours in a wet ball mill (capacity: 5 liters) filled with a steel pulverizing medium having a diameter of 5 mm, and the average particle diameter (Microtrack method D50 (cumulative 50% particle diameter )) A slurry composed of 1 μm powder was prepared. Then, an ammonium fluoride solution having a concentration of 1 mol / l was added to the crushed slurry so that the concentration of fluorine in the polishing material in the final state was 6%, followed by washing with pure water and filtration to obtain a cake. . Next, this cake was dried, roasted at 900 ° C. for 3 hours, ground again, and then classified to obtain a cerium-based abrasive.
【００３３】そして、製造されたセリウム系研摩材を用
いて、ガラス材料の研摩試験を行い、研摩面の評価を行
なった。この研摩試験は、各研摩材を水に分散させて１
０重量％の研摩材スラリーとし、この研摩材スラリーに
て６５ｍｍφの青色ガラスを被研摩材として発泡ウレタ
ン製の研摩パッドを用いて研摩した。研摩条件は、研摩
材スラリーを５Ｌ／ｍｉｎの速度で供給し、研摩面に対
する圧力を４．９×１０３Ｐａに設定して研磨機の回転
速度を１２０ｒｐｍとした。尚、この研摩材スラリーは
研摩試験中、攪拌機にて常時攪拌し、研摩材が沈降しな
いようにした。研摩後のガラス材料は、純水で洗浄し無
塵状態で乾燥させた。Then, using the produced cerium-based abrasive, a glass material was subjected to an abrasive test and the polished surface was evaluated. This polishing test consists of dispersing each abrasive in water and
A polishing agent slurry of 0% by weight was prepared. With this polishing agent slurry, blue glass having a diameter of 65 mm was polished as a polishing material using a polishing pad made of urethane foam. The polishing conditions were such that the abrasive slurry was supplied at a rate of 5 L / min, the pressure on the polishing surface was set to 4.9 × 10 3 Pa, and the rotation speed of the polishing machine was 120 rpm. The abrasive slurry was constantly stirred with a stirrer during the polishing test so that the abrasive did not settle. The glass material after polishing was washed with pure water and dried without dust.
【００３４】研摩面の評価は、研摩面の傷の有無、及
び、ＡＦＭ（原子間力顕微鏡）により、研摩面の任意の
面（２μｍ×２μｍ）の表面粗さを測定し、その最大値
Ｒｍａ ｘにより評価した。研摩材粒子の研摩面への残存
の有無を基準として評価した。研摩面の傷の有無は、研
摩後のガラスの表面に３０万ルクスのハロゲンランプを
照射し、反射法にてガラス表面を観察し、傷の程度（大
きさ）を見極めて点数化し、１００点満点からの減点方
式にて評価点を定めた。The evaluation of the polished surface was carried out by checking the presence or absence of scratches on the polished surface and measuring the surface roughness of any surface (2 μm × 2 μm) of the polished surface by AFM (Atomic Force Microscope). It was evaluated by ma x. Evaluation was made based on whether or not the abrasive particles remained on the polished surface. For the presence or absence of scratches on the polished surface, irradiate the surface of the glass after polishing with a halogen lamp of 300,000 lux and observe the glass surface by the reflection method to determine the degree (size) of the scratch and score it to 100 points. Evaluation points were set by a deduction system from full marks.
【００３５】以上の、原料中の硬質粒子の含有量の測定
結果及び研摩試験の結果を表１に示す。Table 1 shows the results of measuring the content of the hard particles in the raw material and the results of the polishing test.
【００３６】[0036]
【表１】 [Table 1]
【００３７】この表１から、実施例に係る研摩材原料は
硬質粒子の含有量が２００ｐｐｍ以下であり、これらの
原料により製造されたせリウム系研摩材による研摩試験
では傷の発生も殆どみられず、また、表面粗さ（Ｒ
ｍａｘ）についても、実施例に係る研摩材原料は、Ｒ
ｍａｘが６０Å以下と極めて優れた値を示した。これに
対して、比較例の研摩材原料は表面粗さに劣る上、研摩
後の研摩面に傷が発生しているのが確認された。From Table 1, the abrasive raw materials according to the examples had a hard particle content of 200 ppm or less, and scars were scarcely observed in the polishing test using the cerium-based abrasive produced from these raw materials. , Surface roughness (R
max ), the abrasive raw material according to the embodiment is R
The max was 60 Å or less, which was an extremely excellent value. On the other hand, it was confirmed that the abrasive raw material of Comparative Example was inferior in surface roughness and that scratches were generated on the polished surface after polishing.
【００３８】[0038]
【発明の効果】以上説明したように本発明に係るセリウ
ム系研摩材原料は、研摩材の傷発生の要因となる硬質粒
子の含有量を所定の範囲内に規定するものである。本発
明によれば、傷発生のおそれのない高精度の研摩面を形
成可能なセリウム系研摩材を製造することができる。ま
た、本発明に係るセリウム系研摩材原料の分析方法は、
任意の製造工程を経たセリウム系研摩材原料について硬
質粒子の含有量を簡易に測定することができる。As described above, the cerium-based abrasive raw material according to the present invention regulates the content of hard particles, which causes scratches in the abrasive, within a predetermined range. According to the present invention, it is possible to manufacture a cerium-based abrasive capable of forming a highly accurate polished surface without the risk of scratches. Further, the analysis method of the cerium-based abrasive raw material according to the present invention,
It is possible to easily measure the content of hard particles in the cerium-based abrasive raw material that has undergone any manufacturing process.
【図１】本実施形態におけるセリウム系研摩材原料の分
析工程の概略。FIG. 1 is an outline of an analysis process of a cerium-based abrasive raw material according to the present embodiment.
Claims (5)
れる酸化希土を含んでなるセリウム系研摩材原料におい
て、 ケイ素、アルミニウム、ジルコニウムの少なくともいず
れか一の元素を含み、且つ過塩素酸水溶液及び過酸化水
素水溶液に対して溶解性を有しない粒子状物質を含有
し、 前記粒子状物質の含有量は重量比で２００ｐｐｍ以下で
あることを特徴とするセリウム系研摩材原料。1. A cerium-based abrasive material raw material containing rare earth oxide obtained by roasting a rare earth compound, which comprises at least one element of silicon, aluminum and zirconium, and an aqueous solution of perchloric acid and A cerium-based abrasive material raw material containing a particulate matter that is not soluble in an aqueous hydrogen peroxide solution, and the content of the particulate matter is 200 ppm or less in weight ratio.
れる酸化希土を含んでなるセリウム系研摩材原料の分析
方法であって、下記工程よりなるもの。 （ａ）焙焼後のセリウム系研摩材原料からサンプルを採
取し秤量する工程。 （ｂ）前記サンプルに過塩素酸水溶液及び過酸化水素水
溶液を添加し、添加後の溶液を加温する工程。 （ｃ）加温後の溶液をろ過する工程。 （ｄ）濾過後の残渣の重量を測定し、前記試料の重量と
残渣の重量との比を算出する工程。2. A method for analyzing a cerium-based abrasive material raw material containing rare earth oxide, which is obtained by roasting a rare earth compound, comprising the following steps. (A) A step of collecting and weighing a sample from the cerium-based abrasive raw material after roasting. (B) A step of adding an aqueous solution of perchloric acid and an aqueous solution of hydrogen peroxide to the sample and heating the solution after the addition. (C) A step of filtering the solution after heating. (D) A step of measuring the weight of the residue after filtration and calculating the ratio of the weight of the sample to the weight of the residue.
とし、過酸化水素水溶液の濃度を０．１〜５重量％とす
る請求項２記載のセリウム系研摩材原料の分析方法。3. The concentration of the perchloric acid aqueous solution is 5 to 20% by weight.
The method for analyzing a cerium-based abrasive raw material according to claim 2, wherein the concentration of the aqueous hydrogen peroxide solution is 0.1 to 5% by weight.
沸点以下とする請求項２又は請求項３記載のセリウム系
研摩材原料の分析方法。4. The method for analyzing a cerium-based abrasive raw material according to claim 2, wherein the heating temperature of the solution is 80 ° C. or higher and not higher than the boiling point of the solution.
ルターにより行なう請求項２〜請求項４載のセリウム系
研摩材原料の分析方法。5. The method for analyzing a cerium-based abrasive raw material according to claim 2, wherein the filtering step is performed with a filter having a pore size of 0.3 to 5 μm.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005026051A1 (en) * | 2003-09-12 | 2005-03-24 | Hitachi Chemical Co., Ltd. | Cerium salt, process for producing the same, cerium oxide, and cerium-based abrasive material |
| CN102559064A (en) * | 2011-12-15 | 2012-07-11 | 上海华明高纳稀土新材料有限公司 | Cerium-zirconium praseodymium sosoloid and preparation method thereof |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103923602A (en) * | 2013-01-15 | 2014-07-16 | 安阳市岷山有色金属有限责任公司 | Manufacturing method for cerium based abrasive material |
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2001
- 2001-09-28 JP JP2001302406A patent/JP4237957B2/en not_active Expired - Lifetime
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005026051A1 (en) * | 2003-09-12 | 2005-03-24 | Hitachi Chemical Co., Ltd. | Cerium salt, process for producing the same, cerium oxide, and cerium-based abrasive material |
| JP2009274953A (en) * | 2003-09-12 | 2009-11-26 | Hitachi Chem Co Ltd | Method for producing cerium salt, cerium oxide, and cerium-based abrasive material |
| JP2012052121A (en) * | 2003-09-12 | 2012-03-15 | Hitachi Chem Co Ltd | Method for producing cerium salt, cerium oxide and cerium based polishing slurry |
| US8323604B2 (en) | 2003-09-12 | 2012-12-04 | Hitachi Chemical Co., Ltd. | Cerium salt, producing method thereof, cerium oxide and cerium based polishing slurry |
| JP2015091971A (en) * | 2003-09-12 | 2015-05-14 | 日立化成株式会社 | Method for manufacturing cerium salt, cerium oxide and cerium-based polishing agent |
| JP2016216734A (en) * | 2003-09-12 | 2016-12-22 | 日立化成株式会社 | Production method of cerium salt, cerium oxide and cerium-based polishing agent |
| JP2018104711A (en) * | 2003-09-12 | 2018-07-05 | 日立化成株式会社 | Production method of cerium salt, cerium oxide and cerium-based polishing agent |
| CN102559064A (en) * | 2011-12-15 | 2012-07-11 | 上海华明高纳稀土新材料有限公司 | Cerium-zirconium praseodymium sosoloid and preparation method thereof |
| CN102559064B (en) * | 2011-12-15 | 2014-01-29 | 上海华明高纳稀土新材料有限公司 | Cerium-zirconium praseodymium sosoloid and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4237957B2 (en) | 2009-03-11 |
| CN1410502A (en) | 2003-04-16 |
| CN1162500C (en) | 2004-08-18 |
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