JP2002224948A - DETERGENT COMPOSITION FOR ABRASIVE LIQUID FOR MAGNETIC DISK Ni-P SUBSTRATE, AND MANUFACTURING METHOD FOR MAGNETIC DISK Ni-P SUBSTRATE USING THE SAME - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a detergent which effectively removes polishing chips, abrasive grains or the like remaining on the surface after polishing, has performance capabile of preventing the removed polishing chips or abrasive grains from reattaching, and can effectively remove a solidified deposit over which slurry containing polished abrasive grains is scattered. SOLUTION: As the detergent composition for abrasive liquid for a magnetic disk Ni-P substrate, the composition is used in which a hydroxymono- or dicarboxylic acid-based compound of 0.1-50.0 wt.% and a surface active agent of l.0-50.0 wt.% are contained in pure water.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning composition for a polishing liquid for a magnetic disk Ni-P substrate and a method for producing the substrate, and more particularly to a mirror polishing of a magnetic disk substrate, typically an aluminum hard disk substrate. After that, the polishing abrasive grains remaining on the surface, polishing debris, etc. are removed from the polishing surface to prevent re-adhesion, and the slurry containing the abrasive abrasive grains is scattered around the machine, and the solidified substance can be easily washed. ,
Furthermore, the present invention relates to a cleaning composition capable of reducing polishing marks and preventing surface defects due to image sticking, and a method for manufacturing the substrate using the composition.

2. Description of the Related Art Conventionally, a magnetic disk, typically an aluminum hard disk, is obtained by subjecting an aluminum cable disk to roughing and finishing polishing, then subjecting a processed aluminum substrate to Ni-P plating, and further adding alumina and colloidal silica. Polishing with polishing liquid containing colloidal alumina
(Mirror polishing) to produce a plated substrate. here,
After polishing, sponge cleaning using a cleaning agent is performed to remove abrasive grains such as alumina, polishing debris, and the like on the substrate surface. The cleaning agent used here has the ability to prevent the re-attachment of the removed abrasive grains and polishing debris and to discharge the same out of the system as much as possible, in addition to the cleaning and removal of the aforementioned abrasive grains and polishing debris. is necessary. Further, the slurry containing abrasive grains is not only the Ni-P substrate to be polished, but also scatters and adheres around the machine, and the solidified product causes contamination of the substrate surface or occurrence of surface defects on the substrate. Become. Japanese Patent Application Laid-Open No. 10-219300 discloses a polishing liquid detergent having a surface tension of a 10 Vol% aqueous solution measured at 23 ° C. of 30 dyne / cm or less, which has an adsorption amount of 2 mg / m 2 or more to the abrasive, The components of the detergent composition use an anionic surfactant, a nonionic surfactant, a pH adjuster, a chelating agent, etc. to obtain a predetermined adsorption amount and surface tension according to the polishing liquid used. It is disclosed that it is appropriately selected and blended so that
No specific component formulation is shown. In recent years, the density of hard disks has been rapidly increasing, and for that purpose, it is essential to significantly reduce the distance between the disk and the magnetic head, that is, the flying height of the head. In addition, errors in electromagnetic conversion characteristics are becoming more severe, and there is a demand for further reduction in flatness, low surface roughness, scratches, and the like of a recording portion on a substrate. Therefore, adhesion of foreign matter and polishing marks on the substrate surface after polishing are of the highest importance and need to be further reduced in the future. Furthermore, computer prices have fallen in recent years,
There is also an urgent need to reduce substrate manufacturing costs. For that purpose, it is also an important issue to improve the productivity in manufacturing a substrate.

Accordingly, an object of the present invention is to efficiently remove abrasive grains, polishing debris and the like remaining on the surface after polishing, and further remove the removed abrasive grains and polishing debris. An object of the present invention is to provide a cleaning agent having a performance of preventing the re-adhesion of the particles and capable of efficiently removing the individualized adhered matter of the slurry containing the abrasive grains.

The object of the present invention is to provide a detergent containing pure water containing an oxymono- or dicarboxylate compound and a surfactant and, if necessary, a fatty acid, an alkanolamine and an inorganic alkali. It was found that this was suitable for the above purpose, and the present invention was completed. In addition, in addition to applying the cleaning agent to the sponge cleaning which is the next process of the polishing process,
To improve production efficiency, we have also developed technology applicable to the polishing process. That is, the polishing condition of the magnetic disk substrate is generally to optimize the load and the rotation speed in 4 to 5 steps. For example, in the case of four steps, among the P1, P2, P3, and P4, in the P4 step, it is general that the polishing slurry is not supplied, but pure water is supplied, and polishing is performed with a light load. The main purpose of this step is to remove the polishing slurry from the disk surface. However, when polished with pure water, the abrasive grains and abrasive powder tend to agglomerate, and they are difficult to disperse,
Further, seizure is likely to occur between the cloth and the disk surface. As a result, the slurry tends to remain on the polished surface, and scratches such as polish marks and burn-in scratches tend to occur. Further, the slurry is scattered during polishing and adheres and solidifies not only on the substrate surface but also around the machine of the polishing machine, and it is not preferable because the adhered matter falls off and causes flaws on the substrate surface. The inventor has succeeded in solving these quality abnormalities by supplying the cleaning agent of the present invention to the P4 step in the polishing process.

The oxymono- or dicarboxylic acid compound used in the present invention is specifically gluconic acid, lactic acid, salicylic acid, gallic acid, malic acid, tartaric acid, citric acid or the like and / or an alkali metal salt thereof. , For example, Li, Na, K
And Mg salts can be suitably used. The compounding amount of these compounds is 0.1 to 50.0% by weight based on pure water. More specifically, when the oxymono- or dicarboxylic acid-based compound is oxymono- or dicarboxylic acid, the content is 0.1 to 50.0% by weight, preferably 0.5 to 40.0% by weight. The effect is not particularly remarkable even if it exceeds 50.0% by weight, and it is not economically advantageous. Further, when the compound is an oxymono or dicarboxylate,
It is preferably from 0.1 to 5.0% by weight, particularly preferably from 0.2 to 3.0% by weight. In both cases of less than 0.1% by weight or more than 5.0% by weight, the same phenomenon as that of oxymono or dicarboxylic acid is exhibited.
In the present invention, in polishing after Ni-P plating, when the slurry is alumina abrasive grains and the system is neutral to alkaline, the fatty acid is 1.0 to 30.0% by weight, and the alkanolamine is 2.0 to 50.0%. It is preferable to contain 0.3% to 5.0% by weight of an inorganic alkali. As the fatty acid used at this time, either a saturated fatty acid or an unsaturated fatty acid can be used, and specifically, pelargonic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, and pentadecylic acid having eight or more carbon atoms are used. , Palmitic acid,
Castor oil fatty acids, saturated fatty acids such as oleic acid and stearic acid, and unsaturated fatty acids such as elaidic acid, linoleic acid, and linolenic acid can be used. The addition amount is based on pure water.
If the amount is less than 1.0%, a large amount of polish marks are considered to be considered as insufficient lubrication. If the amount is more than 30.0%, stable preparation of a stock solution is difficult. Preferably, 3.0
~ 20.0% by weight. Examples of the alkanolamine include, for example, monoethanolamine, diethanolamine, and triethanolamine. The addition amount is 2.0 to 50.0% by weight based on pure water, and if less than 2.0%, the production of fatty acid amine salt becomes insufficient, and as a result, the stock solution becomes unstable. If it exceeds 50.0%, it is difficult and uneconomical to make a stable stock solution adjustment. Preferably, 3.0 to 20.
0% by weight. Inorganic alkalis are typically KOH, Na
OH, etc. can be exemplified.
If the content is less than 0.3%, it is difficult to prevent re-adhesion of the washed and removed material. Adversely affect the health of the body, for example, rough skin of the hands. Preferably it is 0.5 to 3.0% by weight. Surfactants used in the present invention are known anionic surfactants,
It does not prevent the use of one or more of a cationic surfactant, a nonionic surfactant and an amphoteric surfactant.
Specifically, stearyl alcohol ethylene oxide adduct, oleyl alcohol ethylene oxide adduct, oleyl alcohol ethylene oxide adduct, myristyl alcohol ethylene oxide adduct, lauryl alcohol ethylene oxide 3 mol adduct, tallow fatty acid amide ethylene oxide adduct, Examples thereof include sorbitan monooleate, lauric acid diethanolamide, and lauryl alcohol ethylene oxide adduct.
The addition amount is 1.0 to 50.0% by weight based on pure water,
If it is less than 1.0%, the slurry remains more, and if it is more than 50.0%, firing during processing is severe, which is not preferable. Preferably, it is 3.0 to 30.0% by weight. In the present invention, in polishing after Ni-P plating, the slurry is Ti
When O abrasive grains are used and the slurry system is acidic, it is particularly preferable to use an anionic surfactant. As the anionic surfactant at this time, the following can be further exemplified in addition to the above-mentioned examples. Specifically, Na, Li, NH ₄ salts of lauryl sulfate, salts such as monoethanolamine, diethanolamine, and triethanolamine (anionic active ingredients: 27 to 40%), and Na, Li, NH of lauryl ethoxy sulfate, ₄ salts, salts such as monoethanolamine, diethanolamine, and triethanolamine (anion active ingredient: 27 to 40%), R—O— (CH ₂ CH
₂ O) nSO ₃ M (n = 3 average) (M: Na, triethanolamine),
Other alcohol groups include myristyl, palmityl,
Oleyl and synthetic oxo alcohols (Dovanol 23), Diadol (mixture of C number 13, 13, 15; manufactured by Mitsubishi Chemical Corporation),
Sophthanol (ethoxyoxo alcohol, manufactured by Nippon Shokubai) and nonyl, octyl or dodecylphenol ethoxy (C ₉ H ₁₉ C ₆ H ₄ —O— (CH ₂ CH ₂ O) nSO ₃ M, where n is
4, 6, 7, 9.5, 10, 20, 50 and the like can be exemplified. The cleaning agent of the present invention is preferably used after being diluted with pure water at a concentration of 0.02 to 0.5% by weight. That is, the dilution concentration 0.02
When the amount is less than 0.5% by weight, the amount of deposits such as abrasive grains increases, and when the amount is more than 0.5% by weight, no improvement in the effect on the adhesion and lubricity is observed, which is economically disadvantageous. In addition, there is a concern that trace residues on the disk surface may increase. In addition, the above-mentioned detergent diluent is supplied to the final polishing conditions instead of ordinary pure water for 15 seconds to 120 seconds.
Polish with c. If the polishing time is less than 15 sec, the time for discharging foreign substances such as abrasive grains to the outside of the system is short, and the adhesion preventing effect and the polish mark preventing effect are lacking. On the other hand, if it is longer than 120 sec, no improvement in the effect is observed, and this is not preferable because of the deterioration in productivity and the high cost.

BEST MODE FOR CARRYING OUT THE INVENTION The cleaning composition of the present invention comprises an abrasive in a polishing liquid remaining on the surface after polishing or texturing of a Ni-P plated disk, especially an aluminum disk,
A cleaning composition that efficiently removes polishing debris, prevents reattachment of the removed material, and does not adversely affect the subsequent sponge process after polishing.When actually used, the cleaning composition of the present invention includes: Furthermore, it is diluted with pure water to a concentration of 0.02 to 0.5% by weight, and is applied continuously during polishing after polishing with a slurry.

The following examples are provided to further illustrate the present invention.

Examples 1 to 18 and

Comparative Examples 1 to 9 Substrates were polished under the following experimental conditions, and polished using the cleaning compositions of Examples and Comparative Examples shown in Tables 1 and 2. The surface after polishing is determined by the following evaluation method,
The results are shown in Table 1 (Example) and Table 2 (Comparative Example). <Experiment conditions> (1) Test substrate: 3.75 inch Ni-P substrate (Ni-P film thickness 14 u
m) (2) Processing machine: Speed Fam (9B) (3) Cloth: Rodale PDG (4) Slurry: Fujimi Corporation 4479 (alumina slurry) (5) Slurry and cleaning agent: Flow rate: 0.8 mL / min (6) Detergent concentration: 0.05% (7) Polishing conditions P1: 20g / cm2 23s P2: 70g / cm2 420s P3: 40g / cm2 30s P4: 20g / cm2 See experimental conditions and results P1 to P3 supply polishing slurry , P4 only pure water or cleaning liquid supply (8) Evaluation (a) Evaluation of foreign matter adhesion: Observation and counting of 10 visual fields with an optical microscope (50 times), and evaluation of the number converted to one surface (b) Polish mark evaluation: Halogen projector The front surface was visually evaluated on the 20 sides, and the average number was converted to 1 side.

[Table 1]

[Table 2] In Tables 1 and 2, the remainder when the total amount of each component is 100 ‰ is pure water, and the components such as surfactants, organic acids, fatty acids, and inorganic alkalis are as shown below. used. The surfactants are as follows. (1) Stearyl alcohol ethylene oxide adduct (2) Oleyl alcohol ethylene oxide adduct (3) Oleyl alcohol ethylene oxide adduct (4) Myristyl alcohol ethylene oxide adduct (5) Lauryl alcohol ethylene oxide 3 mol adduct (6) Tallow fatty acid amide ethylene oxide adduct (7) sorbitan monooleate (8) lauric acid diethanolamide (9) lauryl alcohol ethylene oxide adduct

Embodiment 19 and

[Comparative Example 10] With respect to the cleaning agents having the compositions of Example 1 and Comparative Example 1, a cleaning solution diluted with pure water at a dilution concentration of 0.25% by weight was used, and the polishing time was 15 and 120 seconds (Example 19).
The processing was performed in the same manner as in Example 1 except for 10 seconds (Comparative Example 10). Table 3 shows the results.

[Table 3] As shown in the above Tables 1 and 2, the cleaning composition of the present invention comprises:
In the limited amount of addition according to claim 1, the number of deposits on the surface after polishing the substrate, as shown in Examples 1 to 18, any one or less, the polish mark is 3 or less, As shown in Comparative Examples 1 to 11, all of the comparative composition compositions which are out of the range of the addition amount limited in the present invention have the number of attached matter of 1 or more, and the polish mark is 3 or more. If the kimono is 1 or more, there is a risk of crash with the magnetic head when the substrate is mounted. Further, when the polish mark is 3 or more, it is not practical because the electromagnetic conversion characteristics are deteriorated.

Examples 20 to 40; and

Comparative Examples 11 to 15 In the same manner as in Example 1, the test was carried out under the conditions shown in Table 4 (Example) and Table 5 (Comparative Example). However, a 95 mm diameter Ni-P substrate (Ni-P film thickness: 14 μm) was used as a test substrate under the experimental conditions.

[Table 4]

[Table 5] However, (a) to (f) and (1) to (9) of the anionic surfactant in Tables 4 and 5 indicate the following, respectively. The remaining amount of each component is pure water.
%. (A): gluconic acid (gluconic acid is 50% aqueous solution) (b): lactic acid (100% aqueous solution) (c): tartaric acid (d): malic acid (e): salicylic acid (f): citric acid hydrate ( 1) Lauryl alcohol ethylene oxide adduct (average
3 mol) Triethanolamine salt of sulfate (active ingredient: 36% aqueous solution) (2) Sodium lauryl alcohol sulfate (active ingredient: 30% aqueous solution) (3) Myristyl alcohol sulfate triethanolamine salt (active ingredient: 40 % Aqueous solution) (4) Nonylphenol ethoxysulfate (Na,
EO addition mole number 20) (Solid content: 27% aqueous solution) (5) Sophthalanol ethoxy sulfate (Na, EO addition mole number)
3.3) (Active ingredient: 26%) (6) Diadol ethoxy sulfate (EO addition mole number 3) Triethanolamine salt (Active ingredient: 38%) (7) Nonylhenol ethoxy sulfate (EO addition mole number 7) ) Triethanolamine salt (active ingredient: 38%) (8) Alkyl amide ethoxy sulfate (Na, EO)
(3) (active ingredient: 35%) (9) Oleyl ethoxy sulfate ester (Na, EO added mole number: 3) (active ingredient: 40%)

Embodiments 41 and 42; and

Comparative Example 16 The polishing time was 15 and 120 sec (Examples 41 and 4) using the cleaning agent of the composition of Example 21.
2) and 10 sec (Comparative Example 16), and the other processes were the same as in Example 20. Table 6 shows the results.

[Table 6]

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) C11D 10/02 C11D 10/02 (72) Inventor Kazuhiro Hosomi 3-1-1-12 Millennen, Minato-ku, Nagoya Sumitomo Light Metal Industry Co., Ltd. Research and Development Center (72) Inventor Katsuhide Kuroki 3-1-1-12, Minato-ku, Nagoya City Sumitomo Light Metal Industry Co., Ltd. Research and Development Center F-term (reference) 3C058 AB03 AB27 AB31 AB34 AB46 AC03 AC08 AC13 DA15 DB01 EA21 EB08 EB14 ED02 FA15 FA21

Claims (5)

[Claims] An oxymono- or dicarboxylic acid-based compound is added to pure water in an amount of 0.1 to 50.0% by weight and a surfactant in an amount of 1.0 to 50%.
Magnetic disk characterized by containing by weight
Cleaning composition for polishing liquid of Ni-P substrate. 2. The cleaning composition according to claim 1, wherein the oxymono or dicarboxylic acid compound is oxymono or dicarboxylic acid, and the surfactant is an anionic surfactant. 3. The oxymono- or dicarboxylic acid-based compound is oxymono- or dicarboxylic acid or an alkali metal salt thereof, the content of which is 0.1% by weight to 50.0% by weight, and the fatty acid is 1.0% by weight to 30.0% by weight. The detergent composition according to claim 1, which contains 2.0% to 50.0% by weight of an alkanolamine and 0.3% to 5.0% by weight of an inorganic alkali. 4. The cleaning composition according to claim 1, which is added to pure water for 0.0%.
2% to 0.5% by weight of a polishing liquid cleaning solution. 5. A magnetic disk Ni-P, wherein after polishing, the platen is not raised, rotation is not stopped, and the supply is switched from the polishing slurry to the cleaning liquid according to claim 4, and polishing is performed for 15 to 120 seconds. Substrate manufacturing method.