JP2005288576A - Lubricant for polishing and slurry for polishing made of the lubricant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide slurry for polishing having low load to an environment and low toxicity to a human body, and imparting stable and high polishing speed. <P>SOLUTION: In this slurry, (A) a fatty acid having number of carbon atoms 7 to 11, (B) an alkanolamine and/or inorganic alkaline substance, (C) nonionic surface active agent and (D) water are blended. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polishing process lubricator used for polishing a brittle material, a polishing process slurry prepared from the lubrication process, and a brittle material processing method using the slurry.

In recent years, glass materials have been used as glass substrates for optical lenses, optical disks, magnetic disks, liquid crystal glass, photomasks, and the like. In these applications, since it is necessary to process the glass material with high accuracy, a polishing method is mainly used.
At the time of polishing, coupling agents such as sodium metaphosphate, potassium metaphosphate, EDTA and derivatives thereof, and alcohol are widely used as polishing slurry. Slurries based on polyglycols are also widely used.
However, these polishing slurries are highly toxic to the human body and often cause rough skin. Furthermore, the polishing slurry using polyglycols is difficult to treat the waste liquid, and also shows a high COD value after the treatment. Therefore, the amount of use and the like is limited in consideration of the environmental load.
Therefore, there is a need for a polishing slurry that is environmentally friendly, that is, has a low environmental impact after disposal, is less prone to eutrophication of rivers, lakes, and seas, is less toxic to the human body, and is less likely to cause rough skin. ing.

Further, as polishing slurry, a glass polishing abrasive composition (for example, Patent Document 1), a glass polishing abrasive (for example, Patent Document 2), and the like are also known. However, since these polishing slurries cause foaming and filter clogging during use, they are not satisfactory in terms of obtaining a stable polishing rate.
Accordingly, there is also a need for a polishing slurry that can provide a stable polishing rate with less foaming and filter clogging.

Japanese Patent Laid-Open No. 10-176164 Japanese Patent Laid-Open No. 03-146585

An object of the present invention is to provide a polishing slurry having a low environmental load, low toxicity to the human body, and hardly causing rough skin.
Another object of the present invention is to provide a polishing slurry that provides a stable polishing rate with less foaming and filter clogging.
It is a further object of the present invention to provide a polishing slurry that provides a high polishing rate.
It is a further object of the present invention to provide a polishing lubricant that provides the polishing slurry.
A further object of the present invention is to provide a method for processing a brittle material using the polishing slurry.

As a result of intensive studies to solve the above problems, the present inventors have found that a lubricant containing a specific fatty acid, alkanolamine and / or inorganic alkali component, nonionic surfactant and water in a specific ratio has a low environmental load. The present inventors have found that a slurry for polishing can be provided that has low toxicity to the human body and that can provide a stable and high polishing rate with less foaming. The present invention has been completed based on this finding.
That is, the present invention
A lubricant for polishing, comprising (A) a fatty acid having 7 to 11 carbon atoms, (B) an alkanolamine and / or an inorganic alkaline substance, (C) a nonionic surfactant, and (D) water. Lubricant for polishing processing;
Polishing slurry comprising: 100 parts by weight of the polishing lubricant diluted with water 1 to 100 times by weight, and 1 to 50 parts by weight of abrasive grains; and the polishing process It is a processing method of a brittle material characterized by using a slurry for the use.

  The polishing process lubricant of the present invention can be suitably used as a polishing process slurry having a low environmental load, low toxicity to the human body, and capable of providing a stable and high polishing rate.

Hereinafter, the present invention will be described in detail.
The component (A) contained in the polishing process lubricant of the present invention is a fatty acid having 7 to 11, preferably 8 to 11 and particularly preferably 9 to 11 carbon atoms. It is preferable for the fatty acid to have 7 to 11 carbon atoms because foaming when it becomes a salt in the lubricant can be suppressed. In addition, branched fatty acids are preferable to linear fatty acids in terms of less foaming.
Specific examples include heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, isoheptanoic acid, isooctanoic acid, isononanoic acid, isodecanoic acid, isoundecanoic acid, neodecanoic acid, undecylenic acid and the like. Of these, octanoic acid, nonanoic acid, isononanoic acid, neodecanoic acid and undecylenic acid are preferred, and nonanoic acid, isononanoic acid, neodecanoic acid and undecylenic acid are particularly preferred.
The fatty acid having 7 to 11 carbon atoms of the component (A) is a known compound per se, and is easily available on the market or can be synthesized.
Moreover, the C7-11 fatty acid of a component (A) can be used individually or in combination of 2 or more types.
The fatty acid content of 7 to 11 carbon atoms of the component (A) in the polishing process lubricant of the present invention is 3 to 50% by mass, preferably 3 to 35% by mass, particularly preferably the total mass of the polishing process lubricant. 3 to 25% by mass.

（式中、Ｒ₁は、直鎖又は分岐した−Ｃ_xＨ_2xＯＨ（ｘは２〜４である）で示される基であり、Ｒ₂及びＲ₃は、同じでも異なっていてもよく、−Ｈ、−ＣＨ₃、−Ｃ₂Ｈ₅、−Ｃ_xＨ_2x+1（ｘは３〜６である）で示されるアルキル基、又は、直鎖又は分岐した−Ｃ_xＨ_2xＯＨ（ｘは２〜４である）で示される基である。） Examples of the alkanolamine of the component (B) contained in the polishing process lubricant of the present invention include those represented by the following formulae.

Wherein R ₁ is a group represented by linear or branched —C _x H _2x OH (x is 2 to 4), and R ₂ and R ₃ may be the same or different, An alkyl group represented by —H, —CH ₃ , —C ₂ H ₅ , —C _x H _{2x + 1} (x is 3 to 6), or a linear or branched —C _x H _2x OH (x Is a group represented by 2-4).)

Specific examples include diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, methyldiethanolamine, dimethylethanolamine, 2-amino-2-methyl-1-propanol, 2- (2-aminoethoxy) ethanol. Diethyl monoisopropanolamine, N, N-dibutylaminoethanol, N, N-di-N-butylaminoisopropanol, N, N-di-N-propylaminoisopropanol, N, N-ditertiary butyldiethanolamine, N, N-ethylenediamine (diisopropanol), N, N-ethylenediamine (diethanol), mono-N-butyldiethanolamine, monoethyldiisopropanolamine, 2-amino-2-methyl ester Nord and the like. Among these, methyldiethanolamine, dimethylethanolamine and triethanolamine are preferable, and triethanolamine is particularly preferable.
Examples of the inorganic alkaline substance of component (B) include potassium hydroxide, sodium hydroxide, lithium hydroxide, potassium carbonate, sodium carbonate and the like. Among these, potassium hydroxide and sodium hydroxide are preferable, and potassium hydroxide is particularly preferable.
The alkanolamine and inorganic alkaline substance of component (B) are known compounds per se and are readily available on the market or can be synthesized.
Moreover, the alkanolamine and inorganic alkaline substance of component (B) can be used alone or in combination of two or more.
The content of the alkanolamine and / or the inorganic alkaline substance as the component (B) in the polishing process lubricant of the present invention is 15 to 50% by mass, preferably 15 to 40% by mass, particularly with respect to the total mass of the polishing process lubricant. Preferably it is 20-40 mass%.
Since the alkanolamine is water-soluble, if it is blended in a large amount with the lubricant, the COD of the waste liquid becomes high and gives a high load to the environment. However, since the amount of alkanolamine used in the present invention is less than the amount of alkanolamine used in conventional polishing process lubricants, the environmental burden can be kept low.

As the nonionic surfactant of the component (C) contained in the polishing process lubricant of the present invention, an alcohol having 10 to 20, preferably 12 to 15, particularly preferably 13, an EO adduct of the alcohol. , PO adduct, EO and PO adduct, polyoxyethylene oleate, sorbitan oleate and alkylamine EO adduct. Specific examples include decanol, decenol, undecanol, undecenol, tridecanol, isotridecanol, isooctanol, isostearyl alcohol, oleyl alcohol, cetyl alcohol, lauryl alcohol EO adduct (preferably having an average EO addition mole number of 4). -7 mol), polyoxyethylene dioleate (preferably having an oxyethylene average mole number of 4 to 10 mol), sorbitan monooleate, laurylamine EO adduct (preferably, average EO added mole number) Of 4 to 8 moles). Among these, sorbitan monooleate, polyoxyethylene dioleate, tridecanol, isotridecanol and isooctanol are preferable, and sorbitan monooleate, polyoxyethylene dioleate, tridecanol and isotridecanol are particularly preferable. .
The nonionic surfactant of component (C) is a compound known per se and is readily available in the market or can be synthesized.
Moreover, the nonionic surfactant of a component (C) can be used individually or in combination of 2 or more types.
The content of the nonionic surfactant of the component (C) in the polishing process lubricant of the present invention is 5 to 60% by mass, preferably 10 to 60% by mass, particularly preferably the total mass of the polishing process lubricant. It is 10-30 mass%.

As the water of the component (D) contained in the polishing process lubricant of the present invention, industrial water, ground water, well water, tap water, distilled water, purified water, pure water, ion-exchanged water and the like can be used. Among these, distilled water, purified water, pure water, and ion exchange water are preferable in terms of scum generation.
The water content is an amount that allows the above-mentioned essential components (A) to (C) and an optional component (E) described later in the polishing process lubricant of the present invention to be contained in a predetermined content.

The polishing process lubricant of the present invention may contain a fatty acid having 16 to 22 carbon atoms as a component (E) in addition to the components (A) to (D). When component (E) is contained, it is preferable in terms of improving the surface roughness.
The carbon number of the fatty acid of component (E) is generally 16 to 22, preferably 18 to 22, and is particularly straight and preferably has 18 carbon atoms. A fatty acid having 16 to 22 carbon atoms is preferable because lubricity of the lubricant is improved.
The fatty acid of component (E) may be a saturated fatty acid or an unsaturated fatty acid, but a fatty acid that is liquid at room temperature is preferred in that the viscosity is low and filter clogging can be suppressed.
Specific examples include palmitic acid, stearic acid, oleic acid, elaidic acid, linoleic acid, linolein sun, castor fatty acid, hardened castor fatty acid, isostearic acid, eicosane and erucic acid. Among these, castor fatty acid, stearic acid and oleic acid are preferable, and stearic acid and oleic acid are particularly preferable.
The fatty acid having 16 to 22 carbon atoms as the component (E) is a known compound per se, and is easily available in the market or can be synthesized.
Moreover, a C16-C22 fatty acid can be used individually or in combination of 2 or more types.
The content of the fatty acid having 16 to 22 carbon atoms of the component (E) in the polishing process lubricant of the present invention is 0.2 to 20% by mass, preferably 0.2 to 15% by mass with respect to the total mass of the polishing process lubricant. %, Particularly preferably 0.2 to 12% by mass.

  The polishing lubricant of the present invention may contain a rust inhibitor such as dodecanedioic acid and dodecyl succinic acid, an ion sequestering agent such as benzotriazole and EDTA, and other antiseptics and antifoaming agents as necessary. Good.

The polishing slurry of the present invention includes a product obtained by diluting the above-mentioned polishing process lubricant with water and abrasive grains.
The dilution factor of the polishing process with water is 1 to 100 times, preferably 10 to 50 times, particularly preferably 20 to 30 times on a mass basis. As abrasive grains, alumina, silica, zirconia, manganese oxide, oxidation Examples thereof include iron, cerium oxide, GC abrasive grains, and diamond powder. Among these, cerium oxide is preferable. The grain size of the abrasive grains is 0.01 to 20 μm, preferably 0.01 to 10 μm, particularly preferably 0.01 to 5 μm.
In the polishing slurry of the present invention, the mixing ratio of the polishing diluted lubricant and abrasive grains is 1 to 50 parts by weight of abrasive grains with respect to 100 parts by weight of polishing lubricant diluted with water, Preferably it is 1-30 mass parts, Most preferably, it is 1-25 mass parts.
The polishing slurry of the present invention can be produced by adding abrasive grains after diluting the polishing lubricant with water to a predetermined magnification.

The polishing slurry of the present invention can be used for polishing a brittle material.
Examples of the brittle material include glass, silicon, silicon carbide, gallium arsenide, sapphire, and quartz. Among these, glass, sapphire, and quartz are preferable, and glass is particularly preferable.
The slurry for polishing processing of the present invention can be suitably used for polishing processing of various glass materials and products such as glass substrates for optical disks and magnetic disks, glass substrates for liquid crystals, optical lenses and photomasks.
The polishing slurry of the present invention can be widely applied not only to the above-described brittle material polishing but also to metal polishing, grinding, polishing, plastic processing, and the like.

  EXAMPLES Next, although an Example is given and this invention is demonstrated further in detail, this invention is not limited by this.

Examples 1-12
Ingredients (A) to (E) shown in Table 1 were mixed in parts by mass shown in Table 1 to prepare each polishing process lubricant.
The following were used as each component used for preparation.

Examples 13-24
Each of the lubricants of Examples 1 to 12 was diluted 25 times (by mass) with water, and cerium oxide (trade name “Mirek E-10”, manufactured by Mitsui Kinzoku Kogyo Co., Ltd.) was added to the resulting dilution. 10 parts by weight (10% by weight with respect to the weight of the diluted polishing lubricant) was added to 100 parts by weight of the diluted product, and dispersed for 10 minutes in a beaker with an ultrasonic disperser to prepare a polishing slurry. .

Comparative Examples 1-12
Components (A) to (E) shown in Table 2 were mixed in the parts by mass shown in Table 2 to prepare each polishing process lubricant.
In the relationship with the essential components (A) to (D) of the present invention, Comparative Examples 1 to 3, 8, and 10 did not contain the component (A), and Comparative Examples 3 to 11 did not contain the component (C). The comparative example 12 consisted only of water and did not contain components (A) to (E).
Each component other than the following used the same reagents as those used in Examples 1-12.

得られた希釈ポリッシング加工用ルブリカントから、実施例１３〜２４と同様の操作にしたがいポリッシング加工用スラリーを調製した。 Comparative Examples 13-24
The lubricants of Comparative Examples 1 to 12 were each diluted with water at the following magnification (mass basis).

Polishing slurry was prepared from the obtained diluted polishing lubricant in the same manner as in Examples 13-24.

Evaluation of Examples and Comparative Examples About the polishing process lubrication and polishing process slurries of the examples and comparative examples, from the viewpoint of defoaming property, polishing speed, surface roughness of the work material, and the number of particles adhering to the work material evaluated.

Evaluation of antifoaming properties Lubricants for polishing in Examples 1 to 12 and Comparative Examples 1 to 12 were evaluated.
The antifoaming property was evaluated by taking 50 ml of a sample in a 100 ml graduated cylinder, shaking it up and down 60 times in 30 seconds, and then allowing to stand, and then evaluating the foam volume (ml) after standing for 30 seconds. The case where the volume of foam was 60 ml or less was regarded as acceptable.

  The results are shown in Table 3. From Table 3, it is understood that by including the components (A), (B), (C) and (D) (the present invention), a polishing slurry having excellent defoaming properties and less foaming can be obtained. . When the foaming is small, the filter is less clogged, so that the abrasive in the slurry can be stably supplied, and the penetration of the foam into the polishing surface can be reduced, so that the processing efficiency is stabilized.

Evaluation of Polishing Speed, Surface Roughness of Work Material, and Number of Adhered Particles on Work Material The polishing slurry of Examples 13 to 24 and Comparative Examples 13 to 24 were evaluated.
As a work material, a chemically tempered glass (φ65 mm, center hole φ20 mm) pre-processed (Ra = 10 mm, Wa = 7 mm on the polishing surface) was used.
Polishing was performed using a single-side polishing machine under the following conditions.

Plate rotation speed: 30 rpm
Work rotation speed: 30rpm
Surface pressure: 190.9 g / cm ²
Slurry flow rate for polishing process: 10 ml / min Work holding method: Water-filled pad polishing time: 10 minutes Work cleaning method: Pure water

The polishing rate was determined to be 2.3 mg / min or more using the mass of the work material polished per minute as an index.
For the surface roughness, the measurement result of the surface of the work material using NEW VIEW 200 manufactured by ZYGO was used as an index, and 10 mm or less was accepted.
The number of adhering particles was also determined to be 5000 or less per 1 mm ² with the measurement result of the work surface using NEW VIEW 200 manufactured by ZYGO as an index.

In general, as the polishing rate increases, the polished surface becomes rough (the surface roughness increases), but as shown in Table 4, the components (A), (B), (C) and (D) are contained (this book) It was found that a polishing slurry can be obtained that gives a high polishing rate while suppressing the polishing surface from being roughened, and can process the surface of the work material with high accuracy.
Moreover, in the slurry of this invention, since the adhesion | attachment particle | grains to a grinding | polishing surface are significantly lower than an acceptance | permission reference value, the load to post-cleaning can be decreased.

  The polishing process lubricant of the present invention can be used as a polishing process slurry.

Claims (13)

Lubricant for polishing,
(A) a fatty acid having 7 to 11 carbon atoms,
(B) an alkanolamine and / or an inorganic alkaline substance,
A lubricant for polishing, comprising (C) a nonionic surfactant and (D) water.   It contains 3 to 50% by mass of component (A), 15 to 50% by mass of component (B), and 5 to 60% by mass of component (C) with respect to the total mass of the polishing process lubricant. Lubricant for polishing.   The polishing process lubricant according to claim 1 or 2, wherein the component (A) is at least one selected from the group consisting of octanoic acid, nonanoic acid, isononanoic acid, neodecanoic acid and undecylenic acid.   The lubrication for polishing process according to claim 3, wherein component (A) is at least one selected from the group consisting of nonanoic acid, isononanoic acid, neodecanoic acid and undecylenic acid.   The lubricant for polishing according to any one of claims 1 to 4, wherein the component (B) is at least one selected from the group consisting of potassium hydroxide, sodium hydroxide, triethanolamine and methyldiethanolamine.   The lubricating agent for polishing according to claim 5, wherein the component (B) is at least one selected from the group consisting of potassium hydroxide, sodium hydroxide and triethanolamine.   The component (C) is at least one selected from the group consisting of sorbitan monooleate, polyoxyethylene dioleate, isotridecanol and isooctadecanol, according to any one of claims 1 to 6. Lubricant for polishing.   The polishing process lubricant according to claim 7, wherein component (C) is at least one member selected from the group consisting of sorbitan monooleate, polyoxyethylene dioleate, and tridecanol.   The polishing according to any one of claims 1 to 8, further comprising at least one selected from the group consisting of palmitic acid, stearic acid, oleic acid, erucic acid, castor fatty acid and hardened castor fatty acid as component (E). Lubricant for processing.   The lubricant for polishing according to claim 9, wherein component (E) is at least one selected from the group consisting of stearic acid and oleic acid.   It comprises 100 parts by mass of the polishing process lubricant according to any one of claims 1 to 10 diluted 1 to 100 times on a mass basis with water, and 1 to 50 parts by mass of abrasive grains. Polishing slurry.   The polishing slurry according to claim 11, wherein the abrasive grains are at least one selected from the group consisting of alumina, silica, zirconia, manganese oxide, iron oxide, cerium oxide, GC abrasive grains, and diamond powder.   A method for processing a brittle material, wherein the polishing slurry according to claim 10 or 12 is used.