JP2002097457A - Cerium-containing abrasive material, its quality inspection method and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a quality inspection method for a cerium-containing abrasive material permitting a simple quality inspection relating to abrasive characteristics of the cerium-containing abrasive material. SOLUTION: The quality inspection method concerns abrasive characteristics of a cerium-containing abrasive material containing a fluorine component and at least 0.5 atom.%, based on Ce, of La and Nd and having a specific surface area of at most 12 m2/g, where the quality inspection is carried out based on the value of B/A, A being a peak intensity of a maximum peak (a) observed within 2θ=5 deg-80 deg and B being a peak intensity of a maximum peak (b) observed at 2θ=27.5±0.3 deg and at a lower angle than the peak (a), in the X-ray diffraction using a copper target and employing the Cu-Kα1 line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for inspecting the quality of a cerium-based abrasive, a method for producing a cerium-based abrasive, and a cerium-based abrasive.

[0002]

2. Description of the Related Art In recent years, glass materials have been used for various purposes. Among them, glass substrates for optical disks and magnetic disks, active matrix LCDs (Liquid
(Crystal Display), color filters for liquid crystal TVs, watches, calculators, LCDs for cameras, glass substrates for displays such as solar cells, glass substrates for LSI photomasks, glass substrates for optical lenses, and optical lenses. High precision surface polishing is required.

In general, cerium-based abrasives containing rare earth oxides, particularly cerium oxide as a main component, are used for polishing the surface of these glass substrates. This is because cerium oxide has several times higher polishing efficiency in glass polishing than zirconium oxide and silicon dioxide.

As a raw material used for the cerium-based abrasive, a rare earth raw material such as a rare earth carbonate, a rare earth hydroxide, a rare earth oxalate, or a rare earth oxide raw material obtained by firing them is generally used. . These rare earth raw materials are
Generally, it is manufactured by removing a part of rare earth (Nd, Pr) and radioactive substances from a bastnasite-based rare earth material or a cerium-containing rare earth material by a known chemical treatment.

A cerium-based abrasive made from rare earth carbonate or rare earth oxide is produced as follows. That is, the raw material is first slurried or wet-pulverized, treated with a mineral acid, and then treated with hydrofluoric acid or ammonium fluoride as necessary. The obtained slurry is filtered, dried and then roasted. Finally, it is pulverized and classified to obtain an abrasive having a predetermined particle size.

[0006]

Incidentally, it is necessary to check whether or not the produced abrasive has predetermined polishing characteristics. That is, it is necessary to ensure that when the glass surface or the like is polished with the manufactured abrasive, a predetermined polishing value is obtained and that no scratch is generated. Conventionally, for such a quality inspection of the abrasive, it is necessary to actually perform an abrasive test, which is troublesome. In addition, there is a demand for producing a cerium-based abrasive capable of obtaining predetermined polishing characteristics according to the application. In addition, there is a demand for a cerium-based abrasive having predetermined abrasive characteristics according to the application.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a quality inspection method for a cerium-based abrasive which can easily perform a quality inspection on the polishing characteristics of the cerium-based abrasive. I do. Another object of the present invention is to provide a method for producing a cerium-based abrasive capable of obtaining a cerium-based abrasive having predetermined polishing characteristics. Another object of the present invention is to provide a cerium-based abrasive having predetermined abrasive characteristics according to the application.

[0008]

SUMMARY OF THE INVENTION In order to improve the machinability of cerium-based abrasives, fluorine (F) has been conventionally contained. This fluorine forms a crystal structure determined in the abrasive depending on the content and the roasting temperature. The inventors of the present invention have conducted intensive studies focusing on this point, and as a result, have completed the present invention. That is, in the cerium-based abrasive, the crystal structure of the fluorine-containing compound shows the following changes according to XRD (X-ray diffraction) measurement. (1) At the time of adding fluorine, it is present as LnF ₃ (for example, LaF ₃ ) when an oxide is used as a raw material, and as LnCO ₃ F when using a carbonate as a raw material. (2) by roasting, ionic radius larger Ln is discharged as LnF ₃ amount of solid solution is reduced, and Ln _x O _y
Lattice shrinks and the crystal phase changes. For example, by roasting, La having a large ionic radius has a small solid solution amount and La
Is discharged as F _3, the lattice of Ln _x O _y contracts, for example, crystalline phase from those identified as Ce _0.5 Nd _0.5 O _1.75 by X-ray diffraction, to those identified as Ce _0.75 Nd _0.25 O _1.875 Changes. However, Ce _0.5 Nd _0.5 O _1.75
Or those identified as Ce _0.75 Nd _0.25 O _1.875 :
Even when the Nd content is small, the main peak is obtained, so that it is estimated that the oxide contains La which is usually contained in the cerium-based abrasive in an amount of several tens of atoms relative to Ce. (3) When the roasting temperature is high, the discharged LnF ₃ grows as an LnOF phase (for example, the discharged La).
F ₃ grows as a LaOF phase). This change is due to the fact that the higher the fluorine content, the higher the roasting temperature must be set to Ln.
It does not grow as an OF phase, but grows as an LnOF phase at a lower roasting temperature as the fluorine content is lower. Here, Ln contains at least one element of La (lanthanum), Ce (cerium), and Nd (neodymium). Further, LnF ₃ is, for example, LaF ₃ or CeF _3, LnOF is, for example, LaOF or CeOF, Ln _x O _y is typically 3/2 ≦ y /
x ≦ 2, for example, La ₂ O ₃ , CeO ₂ , Ce _0.5 N
d _0.5 O _1.75 or Ce _0.75 Nd _0.25 O _1.875 .

In such a sintering process, a phenomenon of sintering of fine particles is also observed, and the specific surface area decreases as the crystal phase grows. Furthermore, it is known that the polishing rate, which is called an important polishing value in the polishing characteristics, increases with the growth of the particles, but only the average particle size obtained from the measurement of the particle size distribution generally performed, Although the polishing characteristics could not be estimated, the present inventors
It has been found that an abrasive having excellent polishing characteristics can be provided while adjusting the line diffraction and the specific surface area. That is, it contains a fluorine component, and La and Nd are added in an amount of 0.
A cerium-based abrasive having a content of 5 at% or more and a specific surface area of 12 m ² / g or less. Further, in a X-ray diffraction using a Cu-Kα ₁ ray using a copper target, 2θ
= 5 deg to 80 deg, the maximum peak is a, the peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the maximum peak at a lower angle than peak a is b, and the peak intensity is B, 2θ = When the maximum peak at 26.5 ± 0.5 deg is c and its peak intensity is C,
The present inventors have found that the value of B / A and the value of C / A have a certain relationship with the polishing value and the occurrence of scratches, which are the polishing characteristics of the cerium-based abrasive, respectively, and have reached the present invention.

[0010] The present invention relates to a composition containing a fluorine component,
A method for inspecting the polishing characteristics of a cerium-based abrasive having a specific surface area of not more than 12 m ² / g containing 0.5 at% or more of Nd and Nd with respect to Ce, wherein a Cu-Kα _In X-ray diffraction using _one line, 2
The maximum peak at θ = 5 deg to 80 deg is a, the peak intensity is A, the maximum peak at 2θ = 27.5 ± 0.3 deg and the lower peak than peak a is b,
Provided is a quality inspection method for a cerium-based abrasive, wherein a quality inspection is performed based on a value of B / A when the peak intensity is B. Further, the present invention provides a quality inspection on the polishing characteristics of a cerium-based abrasive containing a fluorine component, containing La and Nd in an amount of 0.5 atomic% or more based on Ce, and having a specific surface area of 12 m ² / g or less. Using a copper target and X-rays using a Cu-Kα ₁ wire.
In the line diffraction, the maximum peak at 2θ = 5 to 80 deg is a, and the peak intensity is A, 2θ = 27.5.
When the maximum peak at ± 0.3 deg and at a lower angle than the peak a is b, and its peak intensity is B,
A quality inspection method for a cerium-based abrasive, wherein a cerium-based abrasive having 0.06 ≦ B / A is determined to be rejected.

The present invention also relates to a polishing characteristic of a cerium-based abrasive containing a fluorine component, containing La and Nd in an amount of 0.5 atomic% or more relative to Ce, and having a specific surface area of 12 m ² / g or less. In a quality inspection method using a copper target, the maximum peak at 2θ = 5 deg to 80 deg is a, and the peak intensity is A, 2θ = 26.5 ± in X-ray diffraction using Cu—Kα ₁ ray. 0.5de
Provided is a quality inspection method for a cerium-based abrasive characterized by performing a quality inspection based on the value of C / A, where c is the maximum peak in g, and C is the peak intensity. The present invention also relates to a composition containing a fluorine component and La and N
A quality inspection method for polishing characteristics of a cerium-based abrasive having a specific surface area of 12 m ² / g or less containing d at least 0.5 atomic% with respect to Ce, using a copper target,
In X-ray diffraction using Cu-Kα ₁ ray, 2θ = 5d
The maximum peak at eg-80 deg is a, the peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the maximum peak at a lower angle than peak a is b, and the peak intensity is B, 2θ = 26. When the maximum peak at 0.5 ± 0.5 deg is c and the peak intensity is C, B / A
And a quality inspection method based on the C / A value.

Further, the present invention provides a method for producing a cerium-based abrasive which contains a fluorine component, contains La and Nd in an amount of 0.5 atomic% or more based on Ce, and has a specific surface area of 12 m ² / g or less. And using a copper target, Cu-
In X-ray diffraction using the K [alpha ₁ line, 2θ = 5deg~
When the maximum peak at 80 deg is a, the peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the maximum peak at a lower angle than peak a is b, and the peak intensity is B, B / A method for producing a cerium-based abrasive characterized by adjusting the fluorine content and the roasting temperature based on the value of A. In addition, the present invention contains a fluorine component, and sets La and Nd to 0.5 to Ce.
A method for producing a cerium-based abrasive containing at least atomic% and having a specific surface area of not more than 12 m ² / g, wherein a copper target is used, and X-ray diffraction using Cu-Kα ₁ line
The maximum peak at θ = 5 deg to 80 deg is a, the peak intensity is A, the maximum peak at 2θ = 27.5 ± 0.3 deg and the lower peak than peak a is b,
Provided is a method for producing a cerium-based abrasive characterized by adjusting the fluorine content and the roasting temperature so that 0.06 ≦ B / A when the peak intensity is B.

Further, the present invention provides a method for producing a cerium-based abrasive containing a fluorine component, containing La and Nd in an amount of 0.5 atomic% or more based on Ce, and having a specific surface area of 12 m ² / g or less. And using a copper target, Cu-
In X-ray diffraction using the K [alpha ₁ line, 2θ = 5deg~
When the maximum peak at 80 deg is a, the peak intensity is A, the maximum peak at 2θ = 26.5 ± 0.5 deg is c, and the peak intensity is C, the fluorine content and the fluorine content are determined based on the value of C / A. A method for producing a cerium-based abrasive characterized by adjusting a firing temperature is provided. The present invention also relates to a composition containing a fluorine component and La and N
This is a method for producing a cerium-based abrasive containing d in an amount of 0.5 atomic% or more with respect to Ce and having a specific surface area of 12 m ² / g or less, wherein a copper target is used and a Cu-Kα ₁ wire is used. In X-ray diffraction, the maximum peak at 2θ = 5 to 80 deg is a, and the peak intensity is A, 2θ = 2.
The maximum peak which is 7.5 ± 0.3 deg and is lower than the peak a is b, and the peak intensity is B, 2θ =
When the maximum peak at 26.5 ± 0.5 deg is c and the peak intensity is C, the fluorine content and the roasting temperature are adjusted based on the value of B / A and the value of C / A. To provide a method for producing a cerium-based abrasive.

The present invention also relates to a cerium-based abrasive containing a fluorine component, containing La and Nd in an amount of 0.5 atomic% or more relative to Ce, and having a specific surface area of 12 m ² / g or less. In a X-ray diffraction using a Cu-Kα ₁ ray using a copper target, 2θ = 5 deg to 80 deg.
Is a, the peak intensity is A, 2θ =
A cerium-based polishing method characterized in that B / A <0.06, where b is the maximum peak at 27.5 ± 0.3 deg, and is lower than peak a, and B is the peak intensity. Provide materials. The present invention also relates to a cerium-based abrasive containing a fluorine component, containing La and Nd in an amount of 0.5 atomic% or more based on Ce, and having a specific surface area of 12 m ² / g or less, wherein the copper target Using Cu-
In X-ray diffraction using the K [alpha ₁ line, 2θ = 5deg~
The maximum peak at 80 deg is a, the peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the maximum peak at an angle lower than the peak a is b, and the peak intensity is B, 2θ = 26.5. When the maximum peak at ± 0.5 deg is c and the peak intensity is C, B / A <0.
06, and 0.05 ≦ C / A ≦ 0.60 is provided.

The present invention also relates to a cerium-based abrasive containing a fluorine component, containing La and Nd in an amount of 0.5 atomic% or more based on Ce, and having a specific surface area of 12 m ² / g or less. In a X-ray diffraction using a Cu-Kα ₁ ray using a copper target, 2θ = 5 deg to 80 deg.
Is a, the peak intensity is A, 2θ =
The maximum peak at 27.5 ± 0.3 deg and at an angle lower than the peak a is b, and the peak intensity is B, 2θ
B / A <0.06 and 0.10 ≦ C / A ≦ 0.60, where c is the maximum peak at = 26.5 ± 0.5 deg, and C is the peak intensity. To provide cerium-based abrasives. Further, the present invention contains a fluorine component, and La and Nd are added to Ce in an amount of 0.
A cerium-based abrasive containing 5 atomic% or more and having a specific surface area of 12 m ² / g or less, using a copper target,
In X-ray diffraction using Cu-Kα ₁ ray, 2θ = 5d
The maximum peak at eg-80 deg is a, the peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the maximum peak at a lower angle than peak a is b, and the peak intensity is B, 2θ = 26. When the maximum peak at 0.5 ± 0.5 deg is c and the peak intensity is C, B / A
Provided is a cerium-based abrasive characterized by ≦ 0.01 and 0.10 ≦ C / A ≦ 0.60.

The present invention also relates to a cerium-based abrasive which contains a fluorine component, contains La and Nd in an amount of 0.5 at% or more with respect to Ce, and has a specific surface area of 12 m ² / g or less. In a X-ray diffraction using a Cu-Kα ₁ ray using a copper target, 2θ = 5 deg to 80 deg.
Is a, the peak intensity is A, 2θ =
The maximum peak at 27.5 ± 0.3 deg and at an angle lower than the peak a is b, and the peak intensity is B, 2θ
B / A ≦ 0.01 and 0.05 ≦ C / A ≦ 0.10, where c is the maximum peak at = 26.5 ± 0.5 deg, and C is the peak intensity. To provide cerium-based abrasives.

[0017] Here, in the case of impurities other than the rare earth, such as rare earth carbonate or oxide rare earth is produced from less raw abrasive, generally the maximum peak a in 2θ = 5deg~80deg is, Ln _x O _y (1 ≦ y / x ≦ 2) [11
1] plane, 2θ = 27.5 ± 0.3 deg, and the maximum peak b at an angle lower than peak a is LnF ₃ when a peak appears, and 2θ = 26.5 ± 2
The maximum peak c at 0.5 deg is LnOF. On the other hand, in the case of an abrasive produced from a raw material containing relatively large amounts of impurities other than rare earths such as bastnaesite, Ln
_x O _y remains the maximum peak, but LnF ₃
Alternatively, if the peak intensity of LnOF is low, the peak of another substance may become the maximum peak in the specified angle range. However, even in such a case, if the peak intensity of the other substances is very small compared to the peak intensity of Ln _x O _y, or, LnF ₃ or LnO
Since it is only slightly larger than the peak intensity of F, there is no problem even if the ratio of the intensity of the maximum peak in the specified angle range is used as an index. In each of the above inventions, the peak intensity is obtained by subtracting the intensity of what is generally called a background or a baseline from the intensity at the top of the peak. A peak having an intensity of 0.5% or more of the peak intensity A is regarded as noise, and a peak having an intensity of less than 0.5% of the peak intensity A is regarded as noise. Therefore, if the intensity is 0.5% or more of the peak intensity A, it is necessary to measure under conditions that can be clearly distinguished from noise. Examples of such measurement conditions include, but are not limited to, measurement conditions in Examples described later. Also, a
As it employs a peak other than that employed in the present invention at the peak of Ln _x O _y and / or as c, LnO
It is conceivable to use a peak other than the one used in the present invention as the peak of F, but the result is the same as that of the method of the present invention after the criterion is changed. Further, a and c employed in the present invention are the largest peaks among the peak intensities. Regarding c, when the peak intensity is low, it is possible to determine the peak of the present invention, but at other peaks, noise and noise can be determined. In some cases, it is impossible to make a distinction and judgment cannot be made.

In the quality inspection method for a cerium-based abrasive according to the present invention, it can be determined that the smaller the value of B / A, the less the occurrence of scratches when a glass surface or the like is polished with this abrasive. When this value is 0.06 or more, it can be determined that the number of scratches increases. Also, C / A
It can be determined that the larger the value is, the larger the polishing value tends to be. Further, based on the value of C / A, it is possible to determine how much polishing value the abrasive has.

Therefore, in the case where a cerium-based abrasive is required that scarcely causes scratches even if the polishing value is somewhat small, the value of B / A may be used as a criterion for determination. That is, a cerium-based abrasive having a B / A value of 0.06 or more may be rejected. Here, when the value of B / A is 0.05 or less, it is preferable because the number of scratches is smaller,
It is more preferably 0.03 or less, and further preferably 0.01 or less. Further, when a cerium-based abrasive which requires a small polishing value is required, scarcely occurs, so the C / A value may be used as a criterion for determination. Thereby, it is possible to determine how much polishing value the abrasive has. In the case where a cerium-based abrasive which scarcely generates scratches and which can obtain a polishing value equal to or more than a predetermined value is required, the values of B / A and C / A are used as criteria for determination. Good. That is, it is sufficient to select a cerium-based abrasive having such a value that the former value is less than 0.06 and a polishing value that requires the latter value is obtained.

In the method for producing a cerium-based abrasive according to the present invention, the content of fluorine is adjusted by treatment with hydrofluoric acid or ammonium fluoride, and the grain growth is adjusted by the roasting temperature. Then, by adjusting the fluorine content and the roasting temperature based on the value of B / A, it is possible to produce a cerium-based abrasive having few scratches when the glass surface or the like is polished. Also, this B /
By adjusting the fluorine content and the roasting temperature so that the value of A does not become 0.06 or more, a cerium-based abrasive having almost no scratch can be manufactured. Here, if the value of B / A is 0.05 or less,
It is preferable because the number of scratches is smaller, more preferably 0.03 or less, and further preferably 0.01 or less.

Further, by adjusting the fluorine content and the roasting temperature based on the value of C / A, it is possible to manufacture a cerium-based abrasive capable of obtaining a polishing value not less than a predetermined value. it can. Also, the value of B / A and C / A
By adjusting the fluorine content and the roasting temperature on the basis of the value of the above, it is possible to produce a cerium-based abrasive having almost no scratches and a polishing value of a predetermined value or more can be obtained. it can. That is, the content of B / A does not become 0.06 or more, and the fluorine content and the roasting temperature are adjusted so that the value of C / A becomes a value at which a required polishing value is obtained. You can do it.

Further, in the cerium-based abrasive of the present invention, when the value of B / A is less than 0.06, it can be guaranteed that scars are scarcely generated. Here, it is preferable that the value of B / A is 0.05 or less, because scratches due to polishing are less. More preferably, the value is 0.03 or less, further preferably, 0.01 or less. In the cerium-based abrasive of the present invention, C /
From the value of A, it can be known how much the cerium-based abrasive has a polishing value, and the value of C / A is 0.1.
If it is less than 05, an orange peel is likely to occur and adversely affects the polishing.
Ln _x O _y abrasive for content is less force is lowered.

Further, by selecting the value of B / A and the value of C / A, it is possible to provide a cerium-based abrasive having predetermined polishing characteristics according to the application. That is,
B / A value is less than 0.06 and C / A value is 0.0
In the case of 5 to 0.60, this cerium-based abrasive has almost no scratch due to polishing and can be used as an abrasive having a predetermined practical polishing value. Further, the value of B / A is less than 0.06, and the value of C / A is 0.10-0.
In the case of 60, this cerium-based abrasive is suitable for primary polishing of liquid crystal glass or hard disks. When the value of B / A is 0.01 or less and the value of C / A is 0.10 to 0.60, this cerium-based abrasive is suitable for finish polishing of glass for liquid crystal. Also, B
/ A value is 0.01 or less and C / A value is 0.05
In the case of ０．１0.10, this cerium-based abrasive is suitable for finish polishing of hard disks.

Next, an example of a method for producing a cerium-based abrasive will be described in detail. Cerium-containing rare earth materials include:
Rare earth oxides, rare earth carbonates, bastnaesite and the like are used.
The rare earth oxide can be obtained as a mixed rare earth oxide by firing a carbonate, a hydroxide, an oxalate, or the like of a rare earth material. Bastnaesite is a rare earth fluorocarbonate and is a massive mineral having a Mohs' hardness of 4 to 4.5 and a specific gravity of 4.93 to 5.19.

The cerium-containing rare earth raw material is pulverized,
One having a predetermined particle size is used. The pulverization is performed by a wet ball mill or the like, and the average particle size is set to about 0.5 to 3 μm. Next, when the pulverized cerium-containing rare earth raw material is made of bastnaesite, usually, hydrochloric acid,
Treat with a mineral acid such as sulfuric acid or nitric acid. Mineral acid concentration is 0.1 ~
It is adjusted to about 2 regulations. By this mineral acid treatment, Na,
Since an alkali metal such as Ca and an alkaline earth metal are reduced, abnormal grain growth in a subsequent roasting step can be prevented. On the other hand, when rare earth oxide or rare earth carbonate is used as a raw material, a fluorine-containing substance such as ammonium fluoride, hydrofluoric acid or the like or an aqueous solution thereof is usually added to the slurry for fluorination treatment. The fluorine concentration is preferably about 5 to 100 g / l. Even when bastnaesite is used as a raw material, fluorination treatment may be performed to further increase the fluorine content. Even when rare earth oxide or rare earth carbonate is used as a raw material, a mineral acid treatment may be performed depending on the content of alkali metal and alkaline earth metal in the raw material.

Next, the cerium-containing rare earth raw material that has been subjected to the mineral acid treatment or the fluoridation treatment is dried and then roasted in an electric furnace or the like. The roasting temperature is 600 to 1100 ° C, preferably 700 to 1000 ° C, and the roasting time is about 1 to 10 hours. Next, it is allowed to cool, pulverize, and classify to obtain an abrasive. The average particle size of the abrasive is preferably about 0.05 to 3.0 μm. The abrasive contains 0.5 to 15% by weight, preferably about 1 to 10% by weight of fluorine. The particle size of the abrasive can be controlled by the fluorine content and the roasting temperature. The fluorine content and the roasting temperature are determined by using a specific surface area and a copper target,
In X-ray diffraction using the K [alpha ₁ line, 2θ = 5deg~
The maximum peak at 80 deg is a, the peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the maximum peak at an angle lower than the peak a is b, and the peak intensity is B, 2θ = 26.5. When the maximum peak at ± 0.5 deg is c and its peak intensity is C, the value of B / A
And / or adjusted based on the value of C / A. The measurement of the specific surface area is generally carried out by using BE with nitrogen gas.
Performed by T method. The value of the specific surface area is preferably 12 m ² / g or less, more preferably 10 m ² / g or less, and even more preferably 8 m ² / g or less. Specific surface area is 12m ² /
If the amount exceeds g, even if the crystal grains grow by roasting, a particle size required for increasing the polishing value cannot be obtained, and thus there is a problem in use.

The cerium-based abrasive is usually used in the form of a slurry of about 5 to 30% by weight dispersed in a dispersion medium such as water. As the dispersion medium, a water-soluble organic solvent such as alcohol, polyhydric alcohol, acetone, and tetrahydrofuran can be used, but usually water is used. The cerium-based abrasive desirably contains a polymer organic dispersant. As a dispersant, a polyacrylate such as sodium polyacrylate, carboxymethylcellulose, polyethylene oxide, polyvinyl alcohol and the like can be used. By including this organic dispersant, foaming during polishing can be prevented. The organic dispersant is contained in the abrasive at about 0.1 to 0.8% by weight.
There is no use effect even if the content exceeds this.

[0028]

The present invention will be described below in detail with reference to examples. Total rare earth oxide (TREO) content is 99% by weight, T
The content of CeO _{2 in} REO is 57 to 61% by weight,
Rare earth oxide having a La ₂ O ₃ content of 31 to 34% by weight, a total rare earth oxide content of 67 to 73% by weight, a CeO ₂ content of TREO of 40 to 43% by weight, and a La ₂ content of TREO
Each bastnaesite having an O ₃ content of 24 to 26% by weight was pulverized by a wet ball mill to obtain powder having an average particle size of 1.0 μm. In the case of bastnaesite,
It was treated with a mineral acid (hydrochloric acid at a concentration of 1 N), while in the case of rare earth oxide, it was treated with an aqueous solution of ammonium fluoride having a fluorine concentration of 15 to 25 g / l so that the fluorine content became a predetermined value. Next, this slurry was filtered, dried, and roasted in an electric furnace at a predetermined roasting temperature for 2 hours, then allowed to cool, pulverized, and classified to obtain abrasives 1 to 10 shown in Table 1. Abrasives 1-6
And 10 are manufactured using rare earth oxide as a raw material, and abrasives 7 to 9 are manufactured using bastnaesite as a raw material. The roasting temperature and the quality (fluorine content) of fluorine of each of the abrasives 1 to 10 are as shown in Table 1. For fluorine analysis, alkali melting, hot water extraction, and fluorine ion electrode method were used.

Next, the obtained abrasives 1 to 10 were dispersed in water to obtain a slurry having a concentration of 10% by weight. Using this slurry-like polishing liquid, a glass for a flat panel having a diameter of 65 mm was polished with a high-speed polishing machine at a polishing pressure of 15.7 kg / cm ² . With respect to the glass surface after polishing, the polishing value was measured and the scratches were evaluated. For the measurement of the polishing value, the weight of the flat panel glass before polishing is measured in advance, and the weight of the flat panel glass after polishing is measured to calculate the amount of weight reduction due to polishing. It was converted to the cutting thickness. The evaluation of the scratches was performed on the surface of the flat panel glass after polishing,
A halogen lamp having a light source of 300,000 lux was irradiated and evaluated by a fluoroscopic method and a reflection method. Specifically, 100 points were scored as a perfect score, and the evaluation was performed by a deduction method in which a predetermined score was reduced according to the degree and the number of scratches. Table 1 shows the results. Further, the specific surface area and the degree of agglomeration of the obtained abrasive were measured. The specific surface area was precisely weighed, and the specific surface area was measured using a specific surface area measuring device (a fully automatic surface area measuring device, Multisorb 12 Model, manufactured by Yuasa Ionics Co., Ltd.). The degree of aggregation was measured using a powder tester manufactured by Hosokawa Micron Corporation. In this measurement, 355, 250, 44 μm
A sieve having an opening of was used. Table 1 shows the measurement results.

Further, the obtained abrasives 1 to 10
XRD measurements were made. XRD measurements using a copper target, using a _1-wire Cu-K [alpha, tube voltage 40 kV, tube current 150 mA, measuring range 2θ = 5~80deg,
Sampling width is 0.02deg and scanning speed is 4deg
/ Min. Table 1 shows the results. Further, XRD measurement data of the abrasives 1 and 6 are shown in FIGS. 2 and 3, respectively. XRD intensity (Intensity)
A is the maximum peak at 2θ = 5 deg to 80 deg, and the peak intensity is A, 2θ = 27.5 ± 0.3 deg.
g, the maximum peak at an angle lower than the peak a is b, and the peak intensity is B, 2θ = 26.5 ± 0.5 d
When the maximum peak in the eg was c and the peak intensity was C, A was set to 100 and other XRD intensities were expressed as relative values. Note that, as described above, the intensity is the peak intensity A
Since 0.5% or more of the peak intensity is defined as a peak, the peak intensity B and the peak intensity C are set to 0 when less than 0.5. FIG. 1 shows the relationship between the polishing value and C / A.

[0031]

[Table 1]

As shown in Table 1, the abrasive 10 has a specific surface area of 12
Since it exceeds m ² / g, although the polishing evaluation is good, it can be seen that the polishing value is extremely low, the adhesion to the object to be polished is large, and the performance as an abrasive is inferior. Table 1 and FIG. 1 show that there is a correlation between the C / A and the polishing value in the polishing materials 1 to 9 having a specific surface area of 12 m ² / g or less. That is, the larger the value of C / A, the higher the polishing value tends to be. Also, this C
The polishing value at the time of polishing can be known from the value of / A.

Also, from Table 1, the specific surface area is 12 m ² / g.
In the following abrasives 1 to 9, the abrasives 1 to 4 and the abrasives 7 to 9 have an XRD strength B of 0 and B / A
Is 0, and scratches are hardly generated by polishing. However, when the value of B / A is 0.06 or more, as in the case of the abrasives 5 and 6, the amount of scratches sharply increases. You can see that. This is because the LnOF phase (eg, LaOF)
When the fluorine content is further increased in order to further grow the phase, the polishing value increases, but the normal roasting temperature (6.
At about 100 to 1100 ° C.), the LnOF phase (for example, La
Since the growth of the OF phase is limited, the LnF ₃ phase (for example,
It is considered that the amount of scratches increases because the LaF ₃ phase remains. At this time, in the abrasive 5 and the abrasive 6,
While the value of B / A increases, the value of C / A is slightly smaller than that of the abrasives 3 and 4.

Therefore, it can be determined that the smaller the value of B / A, the less the occurrence of scratches when polishing the glass surface or the like with this abrasive. Can be determined to occur frequently. Also, based on the value of C / A, it is possible to determine how much polishing value the abrasive has.

Further, by adjusting the fluorine content and the roasting temperature based on the value of B / A, a cerium-based abrasive with few scratches can be manufactured. Also,
By adjusting the fluorine content and the roasting temperature so that the value of B / A does not become 0.06 or more, a cerium-based abrasive with almost no scratch can be manufactured. In addition, by adjusting the fluorine content and the roasting temperature based on the value of C / A to manufacture, a cerium-based abrasive capable of obtaining a polishing value equal to or more than a predetermined value can be manufactured. Further, if the fluorine content and the roasting temperature are adjusted on the basis of the B / A value and the C / A value to produce, a scratch is hardly generated and a polishing value equal to or more than a predetermined value can be obtained. Cerium-based abrasives can be manufactured. Specifically, the fluorine content and the roasting temperature are adjusted so that the value of B / A does not become 0.06 or more and the value of C / A becomes a value that can obtain a required polishing value. Then, it may be manufactured.

A cerium-based abrasive having a B / A value of less than 0.06 can guarantee that scratches due to polishing are scarcely generated. Here, this B /
When the value of A is 0.05 or less, it is preferable because scratches due to polishing are smaller, and further preferably 0.03 or less, still more preferably, and 0.01 or less. Also, from Table 1 and FIG. 1, in the case of a cerium-based abrasive having a B / A value and a C / A value of less than 0.06 and 0.05 to 0.60, respectively, almost no scratches occur due to polishing. And an abrasive value of about 23 μm to more than 40 μm can be obtained, so that it can be sufficiently used as an abrasive. In the case of a cerium-based abrasive having a B / A value of less than 0.06 and a C / A value of 0.10 to 0.60, there is almost no scratch due to polishing, and about 25 μm to more than 40 μm Can be suitably used for primary polishing for glass for liquid crystals or hard disks. In the case of a cerium-based abrasive having a B / A value of 0.01 or less and a C / A value of 0.10 to 0.60, scratches due to polishing are almost nil, and about 25 μm to more than 40 μm. Since a polishing value of the order is obtained, it can be suitably used for finish polishing of glass for liquid crystal. Also, B / A
Is 0.01 or less, and the value of C / A is 0.05 to
In the case of a cerium-based abrasive of 0.10, scratches due to polishing are almost nil and a polishing value of about 23 μm to 25 μm is obtained, so that it can be suitably used for finishing polishing of a hard disk.

[0037]

As described above, according to the present invention,
A quality inspection method for a cerium-based abrasive which can easily perform a quality inspection on the polishing characteristics of the cerium-based abrasive can be provided. Therefore, a product inspection is performed using this quality inspection method, and a cerium-based abrasive having predetermined polishing characteristics can be selected. Further, according to the present invention, it is possible to provide a method for producing a cerium-based abrasive capable of obtaining a cerium-based abrasive having predetermined polishing characteristics. Further, according to the present invention, it is possible to provide a cerium-based abrasive having predetermined polishing characteristics according to the application.

[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between a polishing value and C / A.

FIG. 2 is a view showing XRD measurement data of an abrasive 1;

FIG. 3 is a view showing XRD measurement data of an abrasive 1;

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuaki Takahashi 1333-2, Hara-shi, Ageo-shi, Saitama F-term (reference) in Mitsui Kinzoku Mining Co., Ltd. 2G001 AA01 BA18 CA01 GA01 GA13 JA11 KA08 RA03

Claims (13)

[Claims] 1. A composition containing a fluorine component and La and N
The d contains 0.5 atomic% or more with respect to Ce, the specific surface area is a quality inspection method for grinding characteristics of the cerium-based abrasive is less than 12m ² / g, using a copper target, Cu-Kα ₁ In X-ray diffraction using X-rays, the maximum peak at 2θ = 5 deg to 80 deg is a,
When the peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the maximum peak at an angle lower than the peak a is b, and the peak intensity is B, the quality is determined based on the value of B / A. A quality inspection method for cerium-based abrasives, characterized by performing an inspection. 2. A composition containing a fluorine component and La and N
The d contains 0.5 atomic% or more with respect to Ce, the specific surface area is a quality inspection method for grinding characteristics of the cerium-based abrasive is less than 12m ² / g, using a copper target, Cu-Kα ₁ In X-ray diffraction using X-rays, the maximum peak at 2θ = 5 deg to 80 deg is a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
The maximum peak at the lower angle is b, and the peak intensity is B
Wherein a cerium-based abrasive satisfying 0.06 ≦ B / A is determined to be unacceptable. 3. It contains a fluorine component, and contains La and N
The d contains 0.5 atomic% or more with respect to Ce, the specific surface area is a quality inspection method for grinding characteristics of the cerium-based abrasive is less than 12m ² / g, using a copper target, Cu-Kα ₁ In X-ray diffraction using X-rays, the maximum peak at 2θ = 5 deg to 80 deg is a,
When the peak intensity is A, the maximum peak at 2θ = 26.5 ± 0.5 deg is c, and the peak intensity is C, quality inspection is performed based on the value of C / A. Material quality inspection method. 4. A composition containing a fluorine component and La and N
The d contains 0.5 atomic% or more with respect to Ce, the specific surface area is a quality inspection method for grinding characteristics of the cerium-based abrasive is less than 12m ² / g, using a copper target, Cu-Kα ₁ In X-ray diffraction using X-rays, the maximum peak at 2θ = 5 deg to 80 deg is a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
When the maximum peak at a lower angle is b, the peak intensity is B, the maximum peak at 2θ = 26.5 ± 0.5 deg is c, and the peak intensity is C, the value of B / A and the value of C / A A quality inspection method for cerium-based abrasives, wherein a quality inspection is performed based on a value. 5. A composition containing a fluorine component and La and N
The d contains 0.5 atomic% or more with respect to Ce, the specific surface area is a method of producing a cerium-based abrasive is less than 12m ² / g, using a copper target was used _1-wire Cu-K [alpha In the X-ray diffraction, the maximum peak at 2θ = 5 deg to 80 deg is a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
The maximum peak at the lower angle is b, and the peak intensity is B
Wherein the fluorine content and the roasting temperature are adjusted based on the value of B / A. 6. A composition containing a fluorine component and La and N
The d contains 0.5 atomic% or more with respect to Ce, the specific surface area is a method of producing a cerium-based abrasive is less than 12m ² / g, using a copper target was used _1-wire Cu-K [alpha In the X-ray diffraction, the maximum peak at 2θ = 5 deg to 80 deg is a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
The maximum peak at the lower angle is b, and the peak intensity is B
Wherein the fluorine content and the roasting temperature are adjusted so that 0.06 ≦ B / A is not satisfied. 7. A composition containing a fluorine component and La and N
The d contains 0.5 atomic% or more with respect to Ce, the specific surface area is a method of producing a cerium-based abrasive is less than 12m ² / g, using a copper target was used _1-wire Cu-K [alpha In the X-ray diffraction, the maximum peak at 2θ = 5 deg to 80 deg is a,
When the peak intensity is A, the maximum peak at 2θ = 26.5 ± 0.5 deg is c, and the peak intensity is C, it is necessary to adjust the fluorine content and the roasting temperature based on the value of C / A. Characteristic method for producing cerium-based abrasives. 8. A composition containing a fluorine component, La and N
The d contains 0.5 atomic% or more with respect to Ce, the specific surface area is a method of producing a cerium-based abrasive is less than 12m ² / g, using a copper target was used _1-wire Cu-K [alpha In the X-ray diffraction, the maximum peak at 2θ = 5 deg to 80 deg is a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
When the maximum peak at a lower angle is b, the peak intensity is B, the maximum peak at 2θ = 26.5 ± 0.5 deg is c, and the peak intensity is C, the value of B / A and the value of C / A A method for producing a cerium-based abrasive, comprising adjusting the fluorine content and the roasting temperature based on the values. 9. A composition containing a fluorine component and La and N
A cerium-based abrasive containing 0.5 at% or more of d with respect to Ce and having a specific surface area of 12 m ² / g or less, using a copper target and X-ray diffraction using Cu-Kα ₁ ray In the formula, the maximum peak at 2θ = 5 deg to 80 deg is a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
The maximum peak at the lower angle is b, and the peak intensity is B
A cerium-based abrasive characterized in that B / A <0.06. 10. A cerium-based abrasive containing a fluorine component, containing La and Nd in an amount of 0.5 at% or more with respect to Ce, and having a specific surface area of 12 m ² / g or less. In the X-ray diffraction using Cu-Kα ₁ ray, the maximum peak at 2θ = 5 deg to 80 deg was a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
When the maximum peak at a lower angle is b, its peak intensity is B, the maximum peak at 2θ = 26.5 ± 0.5 deg is c, and its peak intensity is C, B / A <0.06, and 0.05 ≦ C / A ≦ 0.60
A cerium-based abrasive characterized by the following. 11. A cerium-based abrasive containing a fluorine component, containing La and Nd in an amount of 0.5 atomic% or more with respect to Ce, and having a specific surface area of 12 m ² / g or less. In the X-ray diffraction using Cu-Kα ₁ ray, the maximum peak at 2θ = 5 deg to 80 deg was a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
When the maximum peak at a lower angle is b, its peak intensity is B, the maximum peak at 2θ = 26.5 ± 0.5 deg is c, and its peak intensity is C, B / A <0.06, and 0.10 ≦ C / A ≦ 0.60
A cerium-based abrasive characterized by the following. 12. A cerium-based abrasive containing a fluorine component, containing La and Nd in an amount of 0.5 atomic% or more with respect to Ce, and having a specific surface area of 12 m ² / g or less. In the X-ray diffraction using Cu-Kα ₁ ray, the maximum peak at 2θ = 5 deg to 80 deg was a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
When the maximum peak at a lower angle is b, the peak intensity is B, the maximum peak at 2θ = 26.5 ± 0.5 deg is c, and the peak intensity is C, B / A ≦ 0.01, and 0.10 ≦ C / A ≦ 0.60
A cerium-based abrasive characterized by the following. 13. A cerium-based abrasive containing a fluorine component, containing 0.5 atomic% or more of La and Nd based on Ce, and having a specific surface area of 12 m ² / g or less. In the X-ray diffraction using Cu-Kα ₁ ray, the maximum peak at 2θ = 5 deg to 80 deg was a,
The peak intensity is A, 2θ = 27.5 ± 0.3 deg, and the peak a
When the maximum peak at a lower angle is b, the peak intensity is B, the maximum peak at 2θ = 26.5 ± 0.5 deg is c, and the peak intensity is C, B / A ≦ 0.01, and 0.05 ≦ C / A ≦ 0.10
A cerium-based abrasive characterized by the following.