JP2015181079A - Cleaning agent composition for magnetic disk substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning agent composition for electronic material which is more excellent in particle removability and organic material removability than the conventional manufacturing method and suppresses corrosion in cleaning.SOLUTION: A cleaning agent composition for magnetic disk substrate includes a compound (A) represented by the following formula (1), and water. The (A) has a solubility parameter of 6-9 and the content of 5-85 wt.% based on the total weight of the (A) and the water. R-[(OA)-OR](1) [In the formula, Rrepresents a residue obtained by removing b hydrogen atoms from C1-C10 hydrocarbon, Reach represents independently a hydrogen atom or C1-C6 hydrocarbon group, Arepresents C2-C4 alkylene group, n is an integer of 0 to 20, Amay be the same or different when n is 2 or more, (OA)portion may be random coupling or block coupling, and b is an integer of 1 to 6.]

Description

  The present invention relates to a magnetic disk substrate cleaning composition and a method for cleaning a magnetic disk substrate using the same.

  Electronic materials, especially magnetic disks, are becoming smaller and higher capacity year by year, and the flying height of magnetic heads is becoming smaller. Therefore, there is a demand for a substrate having no organic matter, abrasive grains, polishing scraps, or the like remaining in the manufacturing process of the magnetic disk substrate.

Magnetic disks include aluminum and glass substrates. For example, in the manufacturing process of an aluminum magnetic disk, after the grinding process (1) for making the thickness of an aluminum alloy substrate as a base material constant, Ni-P (nickel-phosphorus) plating is performed on the surface of the aluminum alloy substrate after grinding. Then, a substrate process (2) for creating a substrate having a polished and flattened surface and a media process (3) for sputtering a magnetic layer on the substrate after the substrate process are included.
Of these, in the grinding process (1), the substrate thickness is made constant and the substrate is processed using a grindstone and a lubricant to reduce roughness and waviness, and then polishing with organic substances such as abrasives remaining on the substrate in the cleaning process Polishing debris generated in is removed.

  In the substrate step (2), polishing with a slurry containing abrasive grains is performed to flatten the substrate, and then the particles such as the slurry and generated polishing waste are rinsed and washed, and further, the particles that cannot be removed by rinsing. Is completely removed by washing in a subsequent washing step.

  On the other hand, in the media step (3), which is a step of sputtering the magnetic layer onto the substrate, cleaning is performed before sputtering in order to remove foreign matters adhering during transportation or storage.

As the capacity of magnetic disks has increased in recent years, the cleanliness of the substrate has been required more than ever, and a higher-performance cleaner than conventional cleaners has become necessary. In order to achieve a severely high recording density of a magnetic disk, it has become necessary to reduce particles and residual particles that are finer than before. In particular, with the recent development of cloud computing, an aluminum substrate is required to have a substrate of 1 TB or more per sheet. Therefore, it is necessary not only to reduce the residual amount of particles more than before, but also to strictly manage the residual amount of organic matter.
For this reason, a cleaning agent has been proposed that has improved the cleaning performance against foreign substances firmly adhered to the substrate. For example, a cleaning agent for a magnetic disk substrate containing a specific nonionic surfactant, a water-soluble amine compound and water has been proposed (Patent Document 1). In addition, a cleaning agent for magnetic disk aluminum substrates containing an alkali metal salt of polyacrylic acid, an alkali metal salt of p-toluenesulfonic acid, a water-soluble amine, a chelating agent and water has been proposed (Patent Document 2).

JP 2011-046807 A JP 2008-007660 A

However, although the cleaning agent of Patent Document 1 has the ability to remove particles adhered to the substrate, the ability to remove organic substances such as lubricants used in the grinding process and organic substances attached during transportation and storage is insufficient. Corrosion of the substrate causes pits.
Further, the cleaning agent of Patent Document 2 is excellent in organic substance removability and aluminum alloy corrosion suppression, but has insufficient particle removability.
Then, it aims at providing the cleaning composition for electronic materials which is excellent in particle removal property and organic substance removal property compared with the conventional cleaning agent, and suppresses the corrosion at the time of cleaning, and the manufacturing method of an electronic material.

As a result of investigations to achieve the above object, the present inventors have not only removed the dirt from the substrate in the cleaning process, but also dissolved in the rinsing process after the cleaning process while maintaining the dispersibility of the particles. As a result, the present inventors have found a magnetic disk substrate cleaning agent for electronic materials and a method for producing the electronic materials, which can prevent the precipitation of the above components and have no flash point and excellent safety.
The compound (A) represented by the following formula (1) and water are included, the solubility parameter of (A) is 6 to 9, and the content of (A) is the total weight of (A) and water. It is a cleaning composition for a magnetic disk substrate, based on 5 to 85% by weight.
R ¹ -[(OA ¹ ) _n -OR ² ] _b (1)
[Wherein R ¹ is a residue obtained by removing b hydrogen atoms from a hydrocarbon having 1 to 10 carbon atoms, R ² is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and A ¹ is a carbon atom having 2 to 4 carbon atoms. Alkylene group, n is an integer of 0 to 20, A ¹ when n is 2 or more may be the same or different, (OA ¹ ) _n part may be a random bond or a block bond, b is 1 to 6 Is an integer. ]

  In the manufacturing process of the magnetic disk substrate (aluminum alloy substrate plated with glass, aluminum alloy or nickel-phosphorus (Ni-P) alloy), the cleaning agent for magnetic disk substrate for electronic material and the method for manufacturing electronic material of the present invention are provided. It has a feature that it can be efficiently cleaned without damaging the substrate. Therefore, it is possible to provide a magnetic disk substrate having high cleanliness required for increasing the recording density of the magnetic disk.

  In the present invention, the magnetic disk substrate is not particularly limited, and examples thereof include a glass substrate for magnetic disk, an aluminum alloy, or an aluminum substrate for magnetic disk whose surface is Ni-P plated.

The cleaning agent of the present invention contains the compound (A) represented by the following formula (1) and water, and the solubility parameter is 6-9.
R ¹ -[(OA ¹ ) _n -OR ² ] _b (1)

In formula (1), R ¹ is a residue obtained by removing b hydrogen atoms from a hydrocarbon having 1 to 10 carbon atoms, R ² is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and A ¹ is a carbon number. An alkylene group of 2 to 4, n is an integer of 0 to 20, and A ¹ when n is 2 or more may be the same or different, (OA ¹ ) _n part may be a random bond or a block bond, b is It is an integer of 1-6.

  The solubility parameter of (A) is 6-9. If it is out of this range, the cleaning performance for the substrate may be inferior or the safety may be inferior. The solubility parameter of (A) is preferably 6.0 to 8.5, particularly preferably 6.5 to 8.5.

In the present invention, the solubility parameter (SP) refers to the square root of the cohesive energy density [Cohesive Energy Density (hereinafter abbreviated as CED)]. This CED indicates the amount of energy required to evaporate a 1 cm ³ substance physicochemically as follows.
(SP) ² = CED = ΔE / V = (ΔH−RT) / V
ΔE: Evaporation energy (Cal / mol)
V: molar capacity (Cm ³ / mol)
ΔH: latent heat of vaporization (Cal / mol)
R: Gas constant (1.987 / mol · ° K)
T: Absolute temperature (° K)

  SP indicates the degree of molecular polarity, that is, the SP value dominates the thermodynamic properties of the solution, and from this value solubility and the like can be regularly predicted or explained. The SP calculation method is Robert F. Faders et al. “Polymer Engineering and Science” published in February 1974, Volume 14, No. 2 or “Solution and Solubility” by Shinoda Kozaburo, Maruzen Co., Ltd., P92-106 Have been described.

  When the cleaning agent of the present invention is used as a cleaning liquid, the content of (A) is 5 to 85% by weight based on the total weight of (A) and water in the active ingredient concentration. When the content of (A) is within the range based on the total weight of (A) and water, it is easy to exert an excellent effect on the removal of attached organic matter, and it is handled without having a flash point. Excellent in terms of safety. From the viewpoint of the same effect, the content of (A) is preferably 20 to 80% by weight, particularly preferably 30 to 80% by weight, and most preferably 40 to 80% by weight.

  As (A) of this invention, a solubility parameter is 6-9, Comprising: A glycol solvent is mentioned.

  Examples of the glycol solvent include ethylene oxide glycol ether (A-1) and propylene oxide glycol ether (A-2).

Examples of the ethylene oxide glycol ether (A-1) include ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl acetate, ethylene glycol-2-butyl ether, ethylene glycol monopentyl ether, Ethylene glycol monohexyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monoallyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monoacetate, diethylene glycol-2-butyl ether , Diethylene glycol monopentyl ether, diethylene glycol monohexyl ether, diethylene glycol mono-2-ethylhexyl ether, diethylene glycol monoallyl ether, diethylene glycol dimethyl ether, diethylene glycol isopropyl methyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monopropyl ether Ether, triethylene glycol monoisopropyl ether, triethylene glycol monobutyl ether, triethylene glycol monoacetate, triethylene glycol-2-butyl ether, triethylene glycol monopentyl ether, triethylene glycol monohexyl ether, triethylene One or more active hydrogen groups selected from the group consisting of glycol mono-2-ethylhexyl ether and triethylene glycol monoallyl ether are selected from the group consisting of methyl group, ethyl group, propyl group, isopropyl group, butyl group and isobutyl group. The etherified substance substituted by 1 or more types selected is mentioned.
More specifically, a methyl etherified product of diethylene glycol monomethyl ether in which the active hydrogen group of diethylene glycol monomethyl ether is substituted with a methyl group, and an isobutyl etherified product of diethylene glycol methyl ether in which the active hydrogen group of diethylene glycol monomethyl ether is substituted with an isobutyl group, etc. Is mentioned.

  As propylene oxide glycol ether (A-2), propylene glycol dimethyl ether, dipropylene glycol dimethyl ether, tripropylene glycol dimethyl ether, propylene glycol ethyl methyl ether, dipropylene glycol methyl ethyl ether, tripropylene glycol ethyl methyl ether, propylene glycol diethyl Ether, dipropylene glycol diethyl ether, tripropylene glycol diethyl ether, propylene glycol methyl propyl ether, dipropylene glycol methyl propyl ether, tripropylene glycol dimethyl ether, propylene glycol monomethyl acetate, propylene glycol monoethyl acetate, propylene glycol Monopropyl acetate, dipropylene glycol monomethyl acetate, dipropylene glycol monoethyl acetate, dipropylene glycol monopropyl acetate, and the like.

In order to stably disperse or solubilize (A) in water, the present invention includes one or more compounds (B) selected from the compound represented by the following formula (2) and a pyrrolidone compound group. The solubility parameter of the compound (B) is more than 9 and 15 or less.
R ³ -[(OA ² ) _m -OR ⁴ ] _c (2)

In formula (2), R ³ is a residue obtained by removing c hydrogen atoms from a hydrocarbon having 1 to 21 carbon atoms, R ⁴ is independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, A ² Is an alkylene group having 2 to 4 carbon atoms, m is an integer of 0 to 20, and A ² when m is 2 or more may be the same or different, and the (OA ² ) _m moiety may be a random bond or a block bond , C is an integer of 1-6.

  As the compound (B), the solubility parameter is more than 9 and 15 or less, and alcohol and diol (B-1), glycol solvent (B-2), nonionic surfactant (B-3), A pyrrolidone compound (B-4) is mentioned.

  Examples of the alcohol and diol (B-1) used in the cleaning agent of the present invention include 1,4-butanediol, 1,3-butanediol, and 2-methyl-2-butanol.

  Examples of the glycol solvent (B-2) used in the cleaning agent of the present invention include ethylene oxide glycol ether (B-2a) and propylene oxide glycol ether (B-2b).

  The ethylene oxide glycol ether of (B-2a) includes ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol-2-butyl ether, ethylene glycol Monopentyl ether, ethylene glycol monohexyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monoallyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl Ether, diethylene glycol-2-butyl ether, diethylene glycol monopentyl ether, diethylene glycol monohexyl ether, diethylene glycol mono-2-ethylhexyl ether, diethylene glycol monoallyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monopropyl ether , Triethylene glycol monoisopropyl ether, triethylene glycol monobutyl ether, triethylene glycol-2-butyl ether, triethylene glycol monopentyl ether, triethylene glycol monohexyl ether, triethylene glycol mono-2-ethylhexyl ether, triethylene glycol mono Ant Ether and the like.

  Examples of the ethylene oxide glycol ether (B-2b) include propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, and dipropylene glycol monopropyl ether.

  As nonionic surfactant (B-3) used for the cleaning agent of the present invention, alkylene oxide addition type nonionic surfactant (B-3a) and polyhydric alcohol type nonionic surfactant (B-3b) ) And the like.

  As (B-3a), except for (B-2), higher alcohol alkylene (2 to 4 carbon atoms) oxide adduct, alkylphenol ethylene oxide (1 to 30 moles added per active hydrogen) adduct, Fatty acid ethylene oxide (addition mole number 1-30 per active hydrogen) adduct, and polyoxyethylene (addition mole number 1-30 per active hydrogen) alkyl (1-20 carbon atoms) allyl ether, sorbitan Multivalent (2 to 8 or more) alcohols (2 to 8 carbon atoms) such as monolaurate ethylene oxide (addition mole number 1 to 30) adduct, sorbitan monooleate ethylene oxide (addition mole number 1 to 30) adduct, etc. 30) fatty acid (carbon number 8-24) ester ethylene oxide adduct (added mole number 1-30 per active hydrogen), etc. And the like.

  As (B-3b), fatty acid (carbon) of polyhydric (2 to 8 or more) alcohol (2 to 30 carbon atoms) such as glycerin monostearate, glycerin monooleate, sorbitan monolaurate, sorbitan monooleate, etc. Formula 8-24) Ester etc. are mentioned.

  Examples of the pyrrolidone compound (B-4) used in the cleaning agent of the present invention include 1-acetyl-2-pyrrolidone, 1-t-butoxycarbonyl-3-pyrrolidone, 1-cyclohexyl-2-pyrrolidone, and 1- (2-hydroxypropyl). ) -2-pyrrolidone, 1-ethyl-2-pyrrolidone, n-octyl-2-pyrrolidone, 4,4-pentamethylene-2-pyrrolidone, 1-phenyl-2-pyrrolidone 5-methyl-2-pyrrolidone, 1- Examples thereof include methyl-2-pyrrolidone, 1-ethyl-2-pyrrolidone, 1-acetyl-2-pyrrolidone, 1-cyclohexyl-2-pyrrolidone and the like.

  The present invention may contain one or more ionic surfactants (C) in order to stably disperse or solubilize (A) in water.

  As the ionic surfactant, an anionic surfactant (C-1), a cationic surfactant (C-2), or an amphoteric surfactant (C-3) may be contained.

  Examples of the anionic surfactant (C-1) include a high molecular weight anionic surfactant (C-1a) and a low molecular weight anionic surfactant (C-1b).

  Polymeric anionic surfactant (C-1a) includes sulfonic acid (salt) group, sulfate ester (salt) group, phosphate ester (salt) group, phosphonic acid (salt) group and carboxylic acid (salt) Examples thereof include polymeric anionic surfactants having at least one group selected from the group consisting of groups and having a weight average molecular weight of 1,000 to 800,000 (hereinafter abbreviated as Mw). The polymer type anionic surfactant usually has at least two repeating units in one molecule. Specific examples of (C-1a) include the following (C-1a-1) to (C-1a-5).

(C-1a-1) a polymeric anionic surfactant having a sulfonic acid (salt) group:
Polystyrene sulfonic acid, styrene / styrene sulfonic acid copolymer, poly {2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid}, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / Styrene copolymer, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / acrylamide copolymer, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / (meth) acrylic acid co Polymer, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / (meth) acrylic acid / acrylamide copolymer, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid / styrene / Acrylamide copolymer, 2- (meth) acryloylamino-2,2-dimethyl eta Sulfonic acid / styrene / (meth) acrylic acid copolymer, naphthalene sulfonic acid formaldehyde condensate, methyl naphthalene sulfonic acid formaldehyde condensate, dimethyl naphthalene sulfonic acid formaldehyde condensate, anthracene sulfonic acid formaldehyde condensate, melamine sulfonic acid formaldehyde condensate And aniline sulfonic acid-phenol-formaldehyde condensate, etc .;

(C-1a-2) a polymeric anionic surfactant having a sulfate (salt) group:
Poly {2-hydroxyethyl (meth) acrylate sulfate}, 2-hydroxyethyl acrylate / 2-hydroxyethyl acrylate sulfate copolymer and 2-hydroxyethyl methacrylate / 2-hydroxyethyl methacrylate sulfate copolymer, poly { 2-hydroxyethyl (meth) acrylate} sulfated ester, poly {(meth) acryloyloxypolyoxyalkylene sulfate}, (meth) acryloyloxypolyoxyalkylene sulfate / acrylic acid copolymer and cellulose, methylcellulose or ethylcellulose Sulfated product of

(C-1a-3) Polymeric anionic surfactant having a phosphate ester (salt) group:
Poly {2-hydroxyethyl (meth) acrylate phosphate}, 2-hydroxyethyl acrylate / 2-hydroxyethyl acrylate phosphate copolymer and 2-hydroxyethyl methacrylate / 2-hydroxyethyl methacrylate phosphate copolymer , Phosphoric acid ester of poly {2-hydroxyethyl (meth) acrylate}, poly {(meth) acryloyloxypolyoxyalkylene phosphoric acid ester}, (meth) acryloyloxy polyoxyalkylene phosphoric acid ester / acrylic acid copolymer And phosphoric acid ester of cellulose, methylcellulose or ethylcellulose;

(C-1a-4) Polymeric anionic surfactant having a phosphonic acid (salt) group:
Poly {(meth) acryloyloxyethyl phosphate}, 2-hydroxyethyl acrylate / acryloyloxyethyl phosphate copolymer and 2-hydroxyethyl methacrylate / methacryloyloxyethyl phosphate copolymer, naphthalenephosphonic acid formaldehyde condensate, methylnaphthalenephosphonic acid Formaldehyde condensate, dimethylnaphthalenephosphonic acid formaldehyde condensate, anthracene phosphonic acid formaldehyde condensate, aniline phosphonic acid-phenol-formaldehyde condensate and the like;

(C-1a-4) Polymeric anionic surfactant having a carboxylic acid (salt) group:
Poly (meth) acrylic acid, (meth) acrylic acid-maleic acid copolymer, (meth) acrylic acid-itaconic acid copolymer, (meth) acrylic acid-fumaric acid copolymer, (meth) acrylic acid / acetic acid Vinyl copolymer and 2-hydroxyethyl methacrylate / (meth) acrylic acid copolymer, poly {2-hydroxyethyl (meth) acrylate} carboxymethylated product, carboxymethylcellulose, carboxymethylmethylcellulose, carboxymethylethylcellulose, benzoic acid formaldehyde Condensates and benzoic acid-phenol-formaldehyde condensates and the like.

  The Mw of (C-1a) is preferably from 1,000 to 800,000, more preferably from 1,200 to 400,000, particularly preferably 1, from the viewpoints of particle reattachment prevention and low foaming properties. 500 to 80,000, most preferably 2,000 to 40,000. Mw in the present invention is measured at 40 ° C. using polyethylene oxide as a reference substance by gel permeation chromatography (hereinafter abbreviated as GPC). Specifically, for example, apparatus main body: HLC-8120 (manufactured by Tosoh Corporation), column: TSKgel α6000, G3000 PWXL, manufactured by Tosoh Corporation, detector: differential refractometer detector built in the apparatus main body, eluent: 0. 5% sodium acetate / water / methanol (volume ratio 70/30), eluent flow rate: 1.0 ml / min, column temperature: 40 ° C., sample: 0.25% eluent solution, injection volume: 200 μl, standard substance : Measured using TSK TANDARD POLYETHYLENE OXIDE manufactured by Tosoh Corporation, data processing software: GPC-8020 model II (manufactured by Tosoh Corporation).

As the low molecular type anionic surfactant (C-1b), a low molecular type sulfonic acid type surfactant (C-1b-1), a low molecular type sulfate ester type surfactant (C-1b-2), Low molecular weight fatty acid surfactant (C-1b-3) and low molecular phosphate ester surfactant (C-1b-4) etc. have a molecular weight (Mw or calculated molecular weight based on structure) of 1, And anionic surfactants of less than 000.
Among the anionic surfactants, the sulfonic acid surfactant (C-1b-1) is a sulfosuccinic acid (mono, di) ester (salt) of an alcohol having 6 to 24 carbon atoms, or an 8 to 24 carbon atoms. α-olefin sulfone oxide (salt), alkylbenzene sulfonic acid (salt) having an alkyl group having 8 to 14 carbon atoms, petroleum sulfonate (salt), toluene sulfonic acid (salt), xylene sulfonic acid (salt), and cumene sulfone Examples include acids (salts). Specific examples of (C-1b-1) include dioctylsulfosuccinic acid (salt), paratoluenesulfonic acid (salt), orthotoluenesulfonic acid (salt), metaxylenesulfonic acid (salt), and paraxylenesulfonic acid (salt). ) And the like.

  Examples of the low-molecular-weight sulfate ester surfactant (C-1b-2) include sulfate esters (salts) of aliphatic alcohols having 8 to 18 carbon atoms, ethylene oxides 1 to 10 of aliphatic alcohols having 8 to 18 carbon atoms. Mole adduct sulfates (salts), sulfated oils (salts), sulfated fatty acid esters (salts), sulfated olefins (salts), and the like. Specific examples of (C-1b-2) include 2-ethylhexanol sulfate (salt), octanol sulfate (salt), 1,10-decandiol disulfate (salt), and ethylene oxide of lauryl alcohol (5 Mol) adduct disulfate (salt) and the like.

  Examples of the low molecular weight fatty acid surfactant (C-1b-3) include fatty acid (salt) having 8 to 18 carbon atoms and ether carboxylic acid (salt) of an aliphatic alcohol having 8 to 18 carbon atoms. Specific examples of (A-2b-3) include n-octanoic acid (salt), 2-ethylhexanoic acid (salt), n-nonanoic acid (salt), isononanoic acid (salt), oleic acid (salt) and Examples include stearic acid (salt).

  Examples of the low molecular phosphate ester surfactant (C-1b-4) include phosphoric acid (mono, di) esters (salts) of higher alcohols having 8 to 24 carbon atoms and higher alcohols having 8 to 24 carbon atoms. Examples include phosphoric acid (mono, di) esters (salts) of alkylene oxide adducts. Specific examples of (A-2b-4) include lauryl alcohol monophosphate (salt), phosphate monoester (salt) of ethylene oxide (5 mol) adduct of lauryl alcohol, and octyl alcohol diphosphate (salt). Etc.

  There are no particular limitations on the counter ion when (C-1) forms a salt, but usually alkali metal (sodium and potassium) salts, ammonium salts, primary amines (alkylamines such as methylamine, ethylamine and butylamine, Monoethanolamine and guanidine etc.) salt, secondary amine (dialkylamine such as dimethylamine, diethylamine and dibutylamine and diethanolamine etc.) salt, tertiary amine {trialkylamine such as trimethylamine, triethylamine and tributylamine, triethanolamine, N-methyldiethanolamine and 1,8-diazabicyclo [5.4.0] -7-undecene (DBU), 1,5-diazabicyclo [4.3.0] -5-nonene (DBN) or 1,4- Diazabicyclo [2.2.2] O Tan (DABCO), 1H imidazole, 2-methyl-1H-imidazole, 2-ethyl-1H-imidazole, 4,5-dihydro-1H imidazole, 2-methyl-4,5-dihydro-1H imidazole, 1,4 5,6-tetrahydro-pyrimidine, 1,6 (4) -dihydropyrimidine etc.} salt and quaternary ammonium salt (tetraalkyl ammonium etc.) salt. Of these, ammonium salts, primary amine salts, secondary amine salts, tertiary amine salts and quaternary ammonium salts are preferred from the viewpoint of metal contamination on the substrate, and tertiary amines are particularly preferred. Salts and quaternary ammonium salts, most preferred are DBU, DBN, DABCO, N-methyldiethanolamine, 1H-imidazole, 2-methyl-1H-imidazole and 2-ethyl-1H-imidazole.

Among the anionic surfactants (C-2), the polymer type anionic surfactant (C-2a) and the low molecular weight sulfonic acid type surfactant (C) are preferable from the viewpoint of preventing the reattachment of particles. -2b-1), low molecular weight sulfate ester surfactant (C-1b-2) and low molecular weight fatty acid surfactant (C-1b-3), more preferably (C-1a) , (C-1b-1) and (C-1b-2), particularly preferably polyacrylic acid (salt), polystyrene sulfonic acid (salt), salt of naphthalene sulfonic acid formalin condensate, acrylamide-2-methylpropane Salt of sulfonic acid / acrylic acid copolymer, salt of methacryloyloxypolyoxyalkylene sulfate / acrylic acid copolymer, octylbenzenesulfonic acid (salt), paratoluenesulfonic acid (salt) Meta-xylene sulfonic acid (salt) and 2-ethylhexanol sulfate (salt).
(C-1) may be used alone or in combination of two or more. From the viewpoint of particle dispersibility, it is more preferable to use two or more kinds in combination.

  As the cationic surfactant (C-2), a quaternary ammonium salt type surfactant (C-2a) {for example, alkyl (C1-30) trimethylammonium salt, dialkyl (C1-30) Dimethyl ammonium salt, nitrogen ring-containing quaternary ammonium salt, poly (addition mole number 2 to 15) oxyalkylene (carbon number 2 to 4) chain-containing quaternary ammonium salt, alkyl (carbon number 1 to 30) amidoalkyl ( Carbon number 1-10) dialkyl (carbon number 1-4) methylammonium salt and the like} and amine surfactant (C-2b) {for example, an aliphatic tertiary amine having 3 to 90 carbon atoms, 3 to 3 carbon atoms 90 alicyclic (including nitrogen-containing heterocycle) tertiary amines and C3-90 hydroxyalkyl group-containing tertiary amine inorganic acid salts or organic acid salts, etc.}.

  As the amphoteric surfactant (C-3): betaine-type amphoteric surfactant (C-3a) {for example, alkyl (C1-30) dimethylbetaine, alkyl (C1-30) amide alkyl (carbon number) 1-4) Dimethylbetaine, alkyl (C1-30) dihydroxyalkyl (C1-30) betaine, sulfobetaine type, etc.}; amino acid type amphoteric surfactant (C-3b) {for example, alanine type [ Alkyl (C1-C30) aminopropionic acid type, alkyl (C1-C30) iminodipropionic acid type, etc.], glycine type [alkyl (C1-C30) aminoacetic acid type, etc.]}; and aminosulfone Salt type amphoteric surfactant (C-3c) {for example, alkyl (C1-30) taurine type amphoteric surfactant}; and the like.

  Of the ionic surfactant (C), the anionic surfactant (C-1) is preferable from the viewpoint of preventing reattachment of particles.

  The content of the ionic surfactant (C) in the cleaning agent of the present invention is preferably 1.5 to 100%, more preferably 2 to 90%, based on the weight of the active ingredient of the cleaning agent of the present invention. Especially preferably, it is 3 to 80%.

  In addition to (A) to (C), the cleaning agent of the present invention may contain a chelating agent (D), a pH adjusting agent (E), and a dispersing agent (F).

As the chelating agent (D), aminopolycarboxylic acid {eg, ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), etc.}, hydroxycarboxylic acid (eg, tartaric acid, citric acid, gluconic acid, etc.), phosphonic acid { For example, 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP) and the like} and condensed phosphoric acid (such as tripolyphosphoric acid) and the like; and salts thereof. Two or more chelating agents of the present invention may be used in combination.
Among these, HEDP and DTPA are preferable from the viewpoint of abrasive cleaning properties.

  Content at the time of use of chelating agent (D) in the cleaning agent of this invention is 0.001 to 5 weight%, Preferably it is 0.01 to 0.5 weight% from a viewpoint of etching resistance.

Examples of the pH adjuster (E) include acids (inorganic acids and organic acids) or alkalis (inorganic alkalis such as sodium hydroxide and potassium hydroxide and amines such as diethanolamine and isopropanolamine).
The pH during use of the cleaning agent of the present invention is 1.0 to 13.0, preferably 4.0 to 12.0, more preferably 8.0 to 12.0 from the viewpoint of inhibiting corrosion resistance.

  Examples of the dispersant (F) include polyethylene glycol (excluding those having an ethylene oxide addition mole number of 41 or less), polyvinyl pyrrolidone, polyvinyl alcohol, polyphosphoric acid, and the like.

  Examples of the electronic material to be cleaned according to the present invention include a magnetic disk substrate (a glass substrate, an aluminum substrate, and an aluminum substrate subjected to Ni-P plating).

  The electronic material cleaning method of the present invention is a cleaning method for cleaning a magnetic disk substrate using the above-described cleaning agent. Objects to be cleaned (dirt) include oils (coolant, etc.), dirt from human bodies (fingerprints, sebum, etc.), plasticizers (dioctyl phthalate, etc.), organic particles and other organic substances and inorganic particles [abrasives (for example, cerium oxide) , Alumina, colloidal silica, diamond, etc.) and polishing scraps (glass cullet, etc.)].

Since the cleaning method of the present invention is extremely excellent in the removal of organic matter, it is performed in the cleaning step after polishing and grinding with an abrasive using organic matter such as coolant in the magnetic disk substrate manufacturing process. More preferably, it is preferably applied as a cleaning method in a cleaning step after the grinding step, a cleaning step after the polishing step, or a cleaning step after the texturing step.
Further, in order to prevent dirt (particles and organic matter dirt, etc.) floating in the atmosphere from firmly attaching to the substrate surface, the substrate may be immersed in the cleaning agent of the present invention before and after the cleaning step. .

  The cleaning method in the cleaning method of the present invention includes at least one cleaning method selected from the group consisting of ultrasonic cleaning, shower cleaning, spray cleaning, brush cleaning, immersion cleaning, immersion rocking cleaning, and single wafer cleaning. In any case, the effect of the cleaning method of the present invention is easily exhibited.

  The washing temperature (° C.) when washing using the cleaning agent of the present invention is preferably 10 to 80 ° C., more preferably 15 to 50, and particularly preferably 20 to 40 from the viewpoint of detergency.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this. Unless otherwise specified, “parts” means “parts by weight” below. The ultrapure water used in the examples and comparative examples had a specific resistance value of 18 MΩ or more.

  Hereinafter, although an example and a comparative example explain the present invention further, the present invention is not limited to these. Hereinafter, unless otherwise specified, “%” represents “% by weight” and “parts” represents “parts by weight”.

Examples 1-7 and Comparative Examples 1-3
Each component was blended so as to have the composition shown in Table 1, and stirred at 25 ° C. with a magnetic stirrer at 40 rpm for 20 minutes to obtain the cleaning agent of the present invention and the cleaning agent for comparison.
The cleaning agent was further diluted 50 times with ultrapure water to prepare a sample solution for performance test.

Various performance evaluation tests with different abrasive grains and substrate materials were performed by the following methods.
This evaluation was conducted in a clean room of class 1,000 (FED-STD-209D, US Federal Standard, 1988) to prevent contamination from the atmosphere.

<Cleanability evaluation-1 (aluminum substrate)>
Oleic acid (manufactured by Wako Pure Chemical Industries, Ltd.) was added to an aqueous solution in which 3.0% of triethanolamine (manufactured by Tokyo Chemical Industry) was dispersed as a model pollutant to prepare an aqueous solution having a pH adjusted to 7.0. 0.5 ml of a model contaminant was dropped on a commercially available aluminum alloy (A5052) plate (thickness 10 mm) cut to 20 mm × 20 mm, and 1 on a 70 ° C. hot plate (PMC Industries, Digital Hot Plate Series 730). A contaminated substrate was prepared by fusing for minutes. It was immersed in 100 ml of cleaning agent at 25 ° C. for 1 minute for cleaning. After cleaning, the substrate was taken out, thoroughly rinsed with ultrapure water, then blown with nitrogen gas and dried, and the substrate surface was cleaned according to the following evaluation points using a differential interference microscope (manufactured by Nikon, OPTIPHOT- 2 and 400 times magnification). This evaluation was performed in a clean room of class 1,000 (FED-STD-209D, US Federal Standard, 1988) to prevent contamination from the atmosphere.
The detergency test was determined according to the following criteria, and the determination results are shown in Table 1.

A: Almost completely removed.
◯: Almost cleaned
Δ: Some particles remain.
X: Almost no washing

<Cleanability test-2 (Ni-P plated aluminum substrate)>
Evaluations were made using the same operation and criteria as in Detergency Test-1, except that a 3.5-inch Ni-P plated aluminum substrate for magnetic disk was used instead of the aluminum alloy (A5052) plate.

<Cleanability test-3 (Glass substrate)>
Evaluations were made using the same operations and criteria as in Detergency Test-1, except that a 2.5-inch commercially available glass substrate for magnetic disk was used instead of the aluminum alloy (A5052) plate.

<Safety>
Safety was evaluated by measuring the flash point of the composition.
The flash point was measured in accordance with the Cleveland Open Act (JISK2265-4), and a composition having no flash point and boiling water was regarded as safe.

By using the magnetic disk substrate cleaning composition of the present invention, a magnetic disk substrate having a high cleanliness can be provided.

Claims (5)

The compound (A) represented by the following formula (1) and water are included, the solubility parameter of (A) is 6 to 9, and the content of (A) is the sum of (A) and water. A cleaning composition for a magnetic disk substrate, which is 5 to 85% by weight based on the weight.
R ¹ -[(OA ¹ ) _n -OR ² ] _b (1)
[Wherein R ¹ is a residue obtained by removing b hydrogen atoms from a hydrocarbon having 1 to 10 carbon atoms, R ² is independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and A ¹ is a carbon number. An alkylene group of 2 to 4, n is an integer of 0 to 20, and A ¹ when n is 2 or more may be the same or different, (OA ¹ ) _n part may be a random bond or a block bond, b is It is an integer of 1-6. ] The cleaning composition for a magnetic disk substrate according to claim 1, comprising a compound (B) represented by the following formula (2), wherein the solubility parameter of the compound (B) is more than 9 and 15 or less.
R ³ -[(OA ² ) _m -OR ⁴ ] _c (2)
[Wherein R ³ is a residue obtained by removing c hydrogen atoms from a hydrocarbon having 1 to 21 carbon atoms, R ⁴ is independently a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and A ² is a carbon number. An alkylene group of 2 to 4, m is an integer of 0 to 20, A ² when m is 2 or more may be the same or different, and the (OA ² ) _m moiety may be a random bond or a block bond, and c is It is an integer of 1-6. ]   The cleaning composition for a magnetic disk substrate according to claim 1, comprising an ionic surfactant (C).   The cleaning composition for a magnetic disk substrate according to any one of claims 1 to 3, wherein the magnetic disk substrate is a glass substrate, an aluminum alloy substrate, or an aluminum alloy substrate plated with Ni-P.   A method for cleaning a magnetic disk substrate using the magnetic disk substrate cleaning composition according to any one of claims 1 to 4, comprising ultrasonic cleaning, shower cleaning, spray cleaning, brush cleaning, immersion cleaning, and immersion rocking cleaning. And a magnetic disk substrate cleaning method performed using one or more cleaning methods selected from the group consisting of single-wafer cleaning.