Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B37/00—Lapping machines or devices; Accessories
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
  • C03C19/00—Surface treatment of glass, not in the form of fibres or filaments, by mechanical means
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09G—POLISHING COMPOSITIONS; SKI WAXES
  • C09G1/00—Polishing compositions
  • C09G1/02—Polishing compositions containing abrasives or grinding agents
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K3/00—Materials not provided for elsewhere
  • C09K3/14—Anti-slip materials; Abrasives
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/84—Processes or apparatus specially adapted for manufacturing record carriers

Definitions

• the present disclosure relates to a polishing liquid composition for a glass hard disk substrate, a method for manufacturing a glass hard disk substrate, and a method for polishing a glass substrate.
• the hard disk mounted on the hard disk drive consumes high power because it rotates at high speed. In recent years, low power consumption has been demanded in consideration of the environment. In order to reduce power consumption, there is a method of increasing the recording capacity per hard disk, reducing the number of hard disks installed in the drive, and reducing the weight. In order to reduce the weight of one substrate, it is necessary to reduce the thickness of the substrate. From this point of view, the demand for a glass substrate having a higher mechanical strength than that of an aluminum substrate has increased, and the recent growth has been remarkable. . In order to improve the recording capacity per substrate, it is necessary to reduce the unit recording area. However, when the unit recording area is reduced, the magnetic signal becomes weak.
• Patent Document 1 proposes an acidic polishing composition containing silica particles having a specific grain diameter and a specific zeta potential.
• Patent Document 2 proposes a polishing liquid composition containing (a) water, (b) a phosphate ester compound, (c) a polishing accelerator, and (d) an abrasive.
• Patent Document 3 proposes a polishing liquid composition containing (A) at least one selected from phosphoric acid, phosphate and phosphoric acid compound, (B) silica, and (C) water.
• a method of polishing the glass substrate with an acidic polishing composition is employed.
• an acidic polishing liquid composition By using an acidic polishing liquid composition, there is an advantage that a leaching action in which alkali ions contained in the glass substrate are eluted during polishing occurs, the hardness of the substrate surface is lowered, and the polishing rate is improved.
• the leaching action works greatly when the pH is low, a brittle leaching layer is generated deeply, and the surface is roughened by alkali etching in the alkali cleaning step after the polishing step. There is a problem that it gets worse significantly.
• the polishing rate and the surface roughness are in a trade-off relationship, and there is a problem that if one improves, the other deteriorates.
• the present disclosure relates to a method for manufacturing a glass hard disk substrate having a step of polishing a glass substrate with an acidic polishing liquid and a step of cleaning.
• a polishing composition for a glass hard disk substrate capable of suppressing deterioration of the surface roughness of the substrate, a method for producing a glass hard disk substrate using the same, and a method for polishing a glass substrate.
• the present disclosure in one aspect, relates to a polishing liquid composition for a glass hard disk substrate, which contains abrasive grains, sulfamic acid, phosphate, and water.
• the present disclosure relates to a method for manufacturing a glass hard disk substrate, including a step of polishing a glass substrate to be polished using the polishing composition of the present disclosure.
• the present disclosure relates to a method for polishing a glass substrate, which includes polishing a glass substrate to be polished using the polishing composition of the present disclosure.
• the polishing liquid composition contains sulfamic acid and phosphate, the polishing rate by the acidic polishing liquid is increased. It is based on the knowledge that deterioration of the surface roughness of the glass substrate due to cleaning can be suppressed while maintaining.
• the present disclosure relates to a polishing liquid composition for glass hard disk substrate (hereinafter, also referred to as “the polishing liquid composition of the present disclosure”) containing abrasive grains, sulfamic acid, phosphate, and water. .
• abrasive grains As abrasive grains (hereinafter, also referred to as “component A”) contained in the polishing composition of the present disclosure, abrasive grains generally used for polishing can be used, and metal, metal, or semimetal Carbides, nitrides, oxides, borides, diamond, and the like.
• the metal or metalloid element is derived from Group 2A, 2B, 3A, 3B, 4A, 4B, 5A, 6A, 7A or Group 8 of the periodic table (long period type).
• component A examples include silicon oxide (hereinafter referred to as silica), aluminum oxide (hereinafter referred to as alumina), silicon carbide, diamond, manganese oxide, magnesium oxide, zinc oxide, titanium oxide, cerium oxide (hereinafter referred to as ceria). ), Zirconium oxide and the like, and the use of one or more of these is preferable from the viewpoint of improving the polishing rate.
• the component A is preferably silica particles or ceria particles, and more preferably silica particles.
• the silica particles include colloidal silica, fumed silica, pulverized silica, and silica obtained by surface modification thereof, and colloidal silica is preferable.
• Component A may be used alone or in combination of two or more.
• the silica particles are, for example, a method based on particle growth using an aqueous alkali silicate solution (hereinafter also referred to as “water glass method”) and a method based on condensation of a hydrolyzate of alkoxysilane (hereinafter referred to as “sol-gel method”). From the viewpoint of ease of production and economy, and preferably obtained by the water glass method. Silica particles obtained by the water glass method and the sol-gel method can be produced by a conventionally known method.
• the shape of the silica particles is not particularly limited, and may be spherical or non-spherical.
• the average particle diameter of component A is preferably 1 nm or more, more preferably 5 nm or more, further preferably 10 nm or more, and 100 nm from the same viewpoint, from the viewpoint of suppressing the deterioration of the surface roughness while maintaining the polishing rate.
• the following is preferable, 70 nm or less is more preferable, and 40 nm or less is still more preferable.
• the average particle size of component A is preferably 1 nm to 100 nm, more preferably 5 nm to 70 nm, and still more preferably 10 nm to 40 nm.
• the average particle diameter of component A can be determined, for example, by the method described in the examples.
• the content of Component A in the polishing liquid composition of the present disclosure is preferably 0.1% by mass or more, more preferably 1% by mass or more, further preferably 3% by mass or more, from the viewpoint of improving the polishing rate. From the viewpoint of suppressing the deterioration of the surface roughness, it is preferably 20% by mass or less, more preferably 15% by mass or less, and still more preferably 10% by mass or less. More specifically, the content of Component A is preferably 0.1% by mass or more and 20% by mass or less, and more preferably 1% by mass or more and 15% by mass or less. When component A is a combination of two or more, the content of component A refers to the total content thereof.
• the content of component A, component B, component C, water, and / or other components is regarded as the blending amount of each component with respect to the total amount (100% by mass) of the polishing composition. Can do.
• “content” can be read as “formulation amount”
• “containing” X can be read as “compounded”.
• the polishing composition of the present disclosure contains sulfamic acid (hereinafter also referred to as “component B”) from the viewpoint of suppressing the deterioration of the surface roughness while maintaining the polishing rate.
• the content of Component B in the polishing composition of the present disclosure is preferably 0.05% by mass or more, more preferably 0.1% by mass or more from the viewpoint of suppressing deterioration of surface roughness while maintaining the polishing rate.
• 0.15% by mass or more is more preferable, 0.3% by mass or more is more preferable, 0.5% by mass or more is more preferable, and from the same viewpoint, 10% by mass or less is preferable, and 7% by mass or less.
• 5% by mass or less is further preferable, 4% by mass or less is further preferable, and 2% by mass or less is further preferable.
• the content of Component B is preferably 0.05% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more and 7% by mass or less, and 0.15% by mass or more and 5% by mass or less. Is more preferably 0.15% by mass or more and 4% by mass or less, and further preferably 0.3% by mass or more and 2% by mass or less.
• the mass ratio A / B (component A content / component B content) of component A and component B in the polishing liquid composition of the present disclosure suppresses deterioration of surface roughness while maintaining the polishing rate. From the viewpoint, 1 or more is preferable, 1.5 or more is more preferable, 2 or more is more preferable, and from the same viewpoint, 100 or less is preferable, 90 or less is more preferable, and 80 or less is more preferable. More specifically, the mass ratio A / B is preferably 1 or more and 100 or less, more preferably 1.5 or more and 90 or less, and still more preferably 2 or more and 80 or less.
• the polishing composition of the present disclosure contains a phosphate (hereinafter also referred to as “component C”) from the viewpoint of suppressing deterioration of surface roughness while maintaining the polishing rate.
• component C is not completely liberated in an aqueous medium at pH 2 (not completely H 3 PO 4 (aq)) from the viewpoint of suppressing the deterioration of the surface roughness while maintaining the polishing rate.
• the phosphate present in the form (ion) is preferred.
• component C is present in salt form (ions) when added to an aqueous medium at pH 2 in the same amount as the phosphate content in the polishing composition.
• component C is sodium dihydrogen phosphate
• 43% by mass of the component C added to the pH 2 aqueous medium is present in the form of salt (ion).
• component C is sodium dihydrogen pyrophosphate
• 96% by weight of component C added to the aqueous medium at pH 2 is present in the salt form (ions).
• the phosphate of component C is preferably an alkali metal phosphate and more preferably an alkali metal hydrogen phosphate from the viewpoint of suppressing deterioration of surface roughness while maintaining the polishing rate.
• alkali metal hydrogen phosphate include dipotassium hydrogen phosphate, disodium hydrogen phosphate, diammonium hydrogen phosphate, potassium dihydrogen phosphate, sodium dihydrogen phosphate, ammonium dihydrogen phosphate, pyrophosphoric acid Examples include sodium dihydrogen (sodium acid pyrophosphate), sodium pyrophosphate, sodium hexametaphosphate, sodium tripolyphosphate, and the like.
• Component C may be used alone or in combination of two or more.
• the content of Component C in the polishing liquid composition of the present disclosure is preferably 0.3% by mass or more, more preferably 0.5% by mass or more from the viewpoint of suppressing deterioration of surface roughness while maintaining the polishing rate.
• 0.8% by mass or more is more preferable, 1% by mass or more is more preferable, and from the same viewpoint, 10% by mass or less is preferable, 7% by mass or less is more preferable, and 5% by mass or less is more preferable. 3 mass% or less is still more preferable.
• the content of component C is preferably 0.3% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 7% by mass or less in one or more embodiments, and 1% by mass.
• the content of Component C is preferably 0.8% by mass or more and 3% by mass or less.
• the content of component C refers to the total content thereof.
• the mass ratio A / C (content of component A / content of component C) of component A and component C in the polishing composition of the present disclosure suppresses deterioration of surface roughness while maintaining the polishing rate. From the viewpoint, 0.5 or more is preferable, 1 or more is more preferable, 1.5 or more is more preferable, and from the same viewpoint, 26 or less is preferable, 20 or less is more preferable, and 16 or less is more preferable. More specifically, the mass ratio A / C is preferably 0.5 to 26, more preferably 1 to 20, and still more preferably 1.5 to 16.
• the mass ratio B / C (component B content / component C content) of component B and component C in the polishing composition of the present disclosure suppresses deterioration of surface roughness while maintaining the polishing rate.
• 0.01 or more is preferable, 0.03 or more is more preferable, 0.05 or more is further preferable, 0.07 or more is further preferable, 0.1 or more is further preferable, and from the same viewpoint, 50
• the following is preferable, 30 or less is more preferable, 20 or less is further preferable, 10 or less is further preferable, 3 or less is further preferable, 2 or less is further preferable, 1 or less is further preferable, and 0.4 or less is further preferable.
• the mass ratio B / C is preferably 0.01 or more and 50 or less, more preferably 0.01 or more and 30 or less, further preferably 0.03 or more and 20 or less, and further preferably 0.05 or more and 10 or less.
• 0.05 to 3 is more preferable, 0.05 to 1 is further preferable, and 0.07 to 0.4 is further preferable.
• the polishing liquid composition of the present disclosure contains water as a medium.
• examples of water include distilled water, ion exchange water, pure water, and ultrapure water.
• the content of water in the polishing liquid composition of the present disclosure can be the remainder excluding Component A, Component B, Component C, and optional components described below.
• the content of water in the polishing liquid composition of the present disclosure is preferably 55% by mass or more, more preferably 70% by mass or more, and 80% by mass because the handling of the polishing liquid composition is further facilitated.
• the water content is preferably 55% by mass or more and 99% by mass or less, more preferably 70% by mass or more and 98% by mass or less, further preferably 80% by mass or more and 97% by mass or less, and 85% by mass or more and 97% by mass or less. The following is more preferable.
• the polishing composition of the present disclosure may further contain other components as necessary.
• other components include acids other than components B and C or salts thereof, oxidizing agents, heterocyclic aromatic compounds, aliphatic amine compounds, alicyclic amine compounds, water-soluble polymers, thickeners, and dispersants. , Antirust agents, basic substances, surfactants, solubilizers, and the like.
• the content of the other components in the polishing liquid composition of the present disclosure is preferably 0% by mass or more, more preferably more than 0% by mass, further preferably 0.1% by mass or more, and 10% by mass or less. Preferably, 5 mass% or less is more preferable. More specifically, the content of other components is preferably 0% by mass to 10% by mass, more preferably more than 0% by mass and 10% by mass or less, and further preferably 0.1% by mass to 5% by mass. .
• the polishing liquid composition of the present disclosure may or may not include a phosphate ester compound. In one or a plurality of embodiments, the polishing liquid composition of the present disclosure may be a polishing liquid composition composed of Component A, Component B, Component C, and water.
• the pH of the polishing composition of the present disclosure is preferably 0.9 or more, more preferably 1 or more, still more preferably 1.5 or more, from the viewpoint of suppressing deterioration of surface roughness while maintaining the polishing rate. From the same viewpoint, 6 or less is preferable, 5 or less is more preferable, and 4.5 or less is more preferable. More specifically, the pH of the polishing composition of the present disclosure is preferably 0.9 or more, 6 or less, more preferably 1 or more and 5 or less, further preferably 1 or more and 4.5 or less, and 1.5 or more and 4. 5 or less is more preferable.
• the pH can be adjusted using the above-described Component B and Component C, a known pH adjusting agent, or the like.
• the pH is the pH of the polishing composition at 25 ° C. and can be measured using a pH meter. For example, the pH meter electrode is immersed in the polishing composition and the value is 2 minutes later. be able to.
• the polishing liquid composition of the present disclosure may be a polishing liquid composition for a glass hard disk substrate formed by blending Component A, Component B, Component C and water.
• the polishing composition of the present disclosure can be produced by blending Component A, Component B, Component C, and water, and, if desired, other components by a known method.
• the present disclosure includes a method for producing a polishing liquid composition (hereinafter referred to as “a method for producing a polishing liquid composition of the present disclosure”, which includes a step of blending at least component A, component B, component C and water. ").
• mixing includes mixing component A, component B, component C and water, and optionally other components simultaneously or in any order.
• the abrasive grains of component A may be mixed in a concentrated slurry state, or may be mixed after being diluted with water or the like.
• component A is composed of a plurality of types of abrasive grains
• the plurality of types of abrasive grains can be blended simultaneously or separately.
• component C consists of a plurality of types of phosphates
• the plurality of types of phosphates can be blended simultaneously or separately.
• blending can be performed using mixers, such as a homomixer, a homogenizer, an ultrasonic disperser, and a wet ball mill, for example.
• the preferable compounding amount of each component in the manufacturing method of the polishing liquid composition of the present disclosure can be the same as the preferable content of each component in the polishing liquid composition of the present disclosure described above.
• the “content of each component in the polishing liquid composition” means the content of each component at the time of use, that is, when the polishing liquid composition starts to be used for polishing.
• the polishing composition of the present disclosure may be stored and supplied in a concentrated state as long as its storage stability is not impaired. In this case, it is preferable in that the manufacturing and transportation costs can be further reduced.
• the concentrate of the polishing liquid composition of the present disclosure may be used by appropriately diluting with the above-described water as necessary at the time of use.
• the dilution rate is not particularly limited as long as the content (in use) of each component described above can be secured after dilution, and can be, for example, 10 to 100 times.
• the present disclosure relates to a kit for producing the polishing liquid composition of the present disclosure (hereinafter, also referred to as “polishing liquid kit of the present disclosure”).
• a polishing liquid kit of the present disclosure for example, a polishing liquid containing an abrasive dispersion liquid containing component A and water and an aqueous additive solution containing component B and component C are not mixed with each other.
• a kit two-pack type polishing composition
• the abrasive dispersion and the additive aqueous solution are mixed at the time of use, and diluted with water as necessary.
• the abrasive dispersion and the additive aqueous solution may further contain other components as described above, if necessary.
• the glass substrate to be polished by using the polishing composition of the present disclosure is a glass substrate used in the manufacturing process of a glass hard disk substrate in one or a plurality of embodiments.
• the material of the glass substrate include quartz glass, soda lime glass, aluminosilicate glass, borosilicate glass, aluminoborosilicate glass, alkali-free glass, and crystallized glass.
• the polishing composition of the present disclosure is suitably used for polishing an aluminosilicate glass substrate or an aluminoborosilicate glass substrate.
• the glass substrate to be polished according to the present disclosure can be used as any of a horizontal magnetic recording substrate, a perpendicular magnetic recording substrate, and a thermally assisted recording (HAMR) substrate.
• HAMR thermally assisted recording
• the shape of the glass substrate to be polished examples include a shape having a flat portion such as a disk shape, a plate shape, a slab shape, and a prism shape, and a shape having a curved surface portion such as a lens.
• a disk-shaped glass substrate to be polished is suitable.
• the outer diameter is, for example, about 2 mm to 100 mm
• the thickness is, for example, about 0.4 mm to 2 mm.
• a glass hard disk substrate is obtained from a process of obtaining a glass substrate by a mold press of molten glass or a method of cutting out from sheet glass, a shape processing process, an end surface polishing process, a rough grinding process, a fine grinding process, a rough polishing process, and a finish polishing. It is manufactured through a process and a chemical strengthening process. The chemical strengthening step may be performed before the finish polishing step. In addition, a cleaning process may be included between the processes.
• the glass hard disk substrate after the polishing process becomes a glass hard disk substrate formed into a magnetic disk through a recording portion forming process including the formation of a magnetic film.
• the polishing composition of the present disclosure is preferably used for polishing (finish polishing) in the final polishing step.
• the present disclosure includes a step of polishing a glass substrate to be polished using the polishing liquid composition of the present disclosure (hereinafter, also referred to as “polishing step using the polishing liquid composition of the present disclosure”). And a glass hard disk substrate manufacturing method (hereinafter also referred to as “substrate manufacturing method of the present disclosure”). According to the substrate manufacturing method of the present disclosure, by using the polishing composition in the present disclosure, an effect that a high-quality magnetic disk substrate can be manufactured with high yield and high productivity can be achieved.
• the polishing step using the polishing liquid composition of the present disclosure is performed by supplying the polishing liquid composition of the present disclosure to the polishing target surface of the glass substrate to be polished, and providing the polishing pad on the polishing target surface. In this step, polishing is performed by moving at least one of the polishing pad and the substrate to be polished while applying contact and applying a predetermined pressure (load). Further, in one or a plurality of other embodiments, the polishing step using the polishing liquid composition of the present disclosure is performed by using a surface plate to which a polishing pad such as a non-woven organic polymer polishing cloth is attached. It is a step of polishing the substrate to be polished by moving the surface plate or the substrate to be polished while sandwiching and supplying the polishing composition of the present disclosure to the polishing machine.
• the polishing process using the polishing composition of the present disclosure is preferably performed in the second stage or later, and is performed in the final polishing process or the final polishing process. Is more preferable.
• different polishing machines may be used, and in the case of using different polishing machines, polishing is performed for each polishing process. It is preferable to clean the substrate.
• the polishing composition of the present disclosure can also be used in cyclic polishing in which the used polishing liquid is reused.
• the polishing machine is not particularly limited, and a known polishing machine for substrate polishing can be used.
• polishing process using the polishing liquid composition of this indication For example, polishing of a suede type, a nonwoven fabric type, a polyurethane independent foam type, or the two-layer type which laminated
• the average pore diameter of the surface member of the polishing pad is preferably 50 ⁇ m or less, more preferably 45 ⁇ m or less, still more preferably 40 ⁇ m or less, further preferably 35 ⁇ m or less, from the viewpoint of improving the polishing rate and the pad life, and the pad polishing liquid From the viewpoint of retention, 0.01 ⁇ m or more is preferable, 0.1 ⁇ m or more is more preferable, 1 ⁇ m or more is further preferable, and 10 ⁇ m or more is more preferable.
• the average opening diameter of the surface member of the polishing pad is preferably 0.01 ⁇ m or more and 50 ⁇ m or less, more preferably 0.1 ⁇ m or more and 45 ⁇ m or less, further preferably 1 ⁇ m or more and 40 ⁇ m or less, and further preferably 10 ⁇ m or more and 35 ⁇ m or less.
• the maximum value of the opening diameter of the polishing pad is preferably 100 ⁇ m or less, more preferably 70 ⁇ m or less, still more preferably 60 ⁇ m or less, and even more preferably 50 ⁇ m or less from the viewpoint of maintaining the polishing rate.
• the polishing load in the polishing step using the polishing liquid composition of the present disclosure is preferably 3 kPa or more, more preferably 4 kPa or more from the viewpoint of improving the polishing rate, and stable so that no vibration is generated in the polishing machine during polishing. From the viewpoint of being able to be polished, it is preferably 40 kPa or less, and more preferably 15 kPa or less. More specifically, the polishing load is preferably 3 kPa or more and 40 kPa or less, and more preferably 4 kPa or more and 15 kPa or less.
• the polishing load refers to the pressure of the surface plate applied to the polishing surface of the substrate to be polished during polishing. The polishing load can be adjusted by applying air pressure or weight to at least one of the surface plate and the substrate to be polished.
• the supply rate of the polishing composition of the present disclosure is 0.01 mL / min or more per 1 cm 2 of the substrate to be polished from the viewpoint of cost reduction and polishing rate improvement.
• / Min or less is preferable, 0.025 mL / min or more and 0.6 mL / min or less is more preferable, 0.05 mL / min or more and 0.4 mL / min or less is more preferable, 0.1 mL / min or more and 0.4 mL / min or less. Is even more preferred.
• the supply flow rate may be higher than the flow rate described above.
• Examples of a method of supplying the polishing composition of the present disclosure to a polishing machine include a method of continuously supplying using a pump or the like.
• a method of continuously supplying using a pump or the like When supplying the polishing composition to the polishing machine, in addition to the method of supplying one component containing all the components, considering the stability of the polishing composition, etc., it is divided into a plurality of compounding component liquids, Two or more liquids can be supplied. In the latter case, for example, the plurality of compounding component liquids are mixed in the supply pipe or on the substrate to be polished to obtain the polishing liquid composition of the present disclosure.
• the substrate manufacturing method of the present disclosure is a method of cleaning a glass substrate (substrate to be cleaned) that has been polished using the polishing liquid composition of the present disclosure, using the cleaning composition described above.
• Step hereinafter also referred to as “cleaning step”.
• the substrate to be cleaned in the cleaning process includes a glass substrate immediately after the polishing process using the polishing composition of the present disclosure, a dipping process in water to prevent drying after the polishing process, a water cleaning process as preliminary cleaning, A glass substrate that has undergone an acid cleaning step or the like is included.
• this cleaning step includes (a) immersing the substrate to be cleaned in the cleaning composition, and / or (b) injecting the cleaning composition on the surface of the substrate to be cleaned. Is performed by supplying a cleaning composition to
• the conditions for immersing the substrate to be cleaned in the cleaning composition may not be particularly limited.
• the temperature of the cleaning composition is 20 ° C. or more and 100 ° C. or less from the viewpoint of safety and operability, and the immersion time is 10 seconds or more from the viewpoint of cleaning performance and production efficiency by the cleaning composition. Within 60 minutes.
• the ultrasonic vibration is applied to the cleaning composition. Examples of the ultrasonic frequency include 20 kHz to 2000 kHz.
• the cleaning agent composition to which ultrasonic vibration is applied is injected to the cleaning substrate surface.
• the surface is contacted to clean the surface, or the cleaning composition is supplied by injection onto the surface of the substrate to be cleaned and then cleaned by rubbing the surface supplied with the cleaning composition with a cleaning brush. It is preferable to do.
• the cleaning composition to which ultrasonic vibration is applied is supplied to the surface to be cleaned by injection, and the surface to which the cleaning composition is supplied is cleaned by rubbing with a cleaning brush. Is preferred.
• known means such as a spray nozzle can be used.
• the cleaning brush include known brushes such as a nylon brush and a PVA (polyvinyl alcohol) sponge brush.
• the ultrasonic frequency may be the same as the value preferably adopted in the method (a).
• the cleaning step may include one or more steps using known cleaning such as rocking cleaning, cleaning using rotation of a spinner, paddle cleaning, and the like. Good.
• an alkaline agent for example, an alkaline agent, water, and various additives as required can be used.
• the alkali agent at least one of an inorganic alkali agent and an organic alkali agent can be used.
• the inorganic alkaline agent include ammonia, potassium hydroxide, and sodium hydroxide.
• the organic alkali agent include at least one selected from hydroxyalkylamine, tetramethylammonium hydroxide, and choline.
• various additives include nonionic surfactants, chelating agents, ether carboxylates, fatty acids, anionic surfactants, water-soluble polymers, antifoaming agents, alcohols, preservatives, antioxidants, and the like. It is done.
• the pH of the cleaning composition used in the cleaning step is preferably 8 or more and 13 or less, for example, from the viewpoint of improving the dispersibility of the residue on the substrate.
• the above pH is the pH of the cleaning composition at 25 ° C. and can be measured using a pH meter (Toa Denpa Kogyo Co., Ltd., HM-30G). For example, the electrode is immersed in the cleaning composition for 3 minutes. Later numbers can be adopted.
• a substrate manufacturing method of the present disclosure includes a step of forming a magnetic film on a glass substrate after a polishing step and a cleaning step of a glass substrate to be polished, or a recording unit formation including formation of a magnetic film You may have a process.
• the present disclosure relates to a glass substrate polishing method (hereinafter, also referred to as “polishing method of the present disclosure”) including polishing a glass substrate to be polished using the polishing composition of the present disclosure.
• polishing method of the present disclosure By using the polishing method of the present disclosure, an effect that a high-quality magnetic disk substrate can be manufactured with high yield and high productivity can be achieved.
• the glass substrate to be polished in the polishing method of the present disclosure include those used for manufacturing a glass hard disk substrate as described above. Specific polishing methods and conditions may be the same methods and conditions as the above-described substrate manufacturing method of the present disclosure.
• Polishing a glass substrate to be polished using the polishing liquid composition of the present disclosure includes supplying the polishing liquid composition of the present disclosure to the surface to be polished of the substrate to be polished in one or a plurality of embodiments.
• a polishing pad is brought into contact with the surface, and polishing is performed by moving at least one of the polishing pad and the substrate to be polished, or a surface plate on which a polishing pad such as a non-woven organic polymer polishing cloth is attached.
• the substrate to be polished is sandwiched and the surface plate or the substrate to be polished is moved to polish the substrate to be polished while supplying the polishing composition of the present disclosure to the polishing machine.
• a polishing liquid composition for a glass hard disk substrate comprising abrasive grains (component A), sulfamic acid (component B), phosphate (component C), and water.
• ⁇ 2> The polishing composition according to ⁇ 1>, wherein component A is silica particles.
• component A is colloidal silica.
• ⁇ 4> The polishing liquid according to any one of ⁇ 1> to ⁇ 3>, wherein the content of component A is preferably 0.1% by mass or more, more preferably 1% by mass or more, and further preferably 3% by mass or more.
• Composition. ⁇ 5> The content of component A is preferably 20% by mass or less, more preferably 15% by mass or less, and further preferably 10% by mass or less, and the polishing composition according to any one of ⁇ 1> to ⁇ 4> .
• the content of Component B is preferably 10% by mass or less, more preferably 7% by mass or less, further preferably 5% by mass or less, further preferably 4% by mass or less, and further preferably 2% by mass or less.
• the content of Component B is preferably 0.05% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more and 7% by mass or less, and further preferably 0.15% by mass or more and 5% by mass or less.
• ⁇ 10> The polishing according to any one of ⁇ 1> to ⁇ 9>, wherein the mass ratio A / B between component A and component B is preferably 1 or more, more preferably 1.5 or more, and still more preferably 2 or more.
• Liquid composition. ⁇ 11> The polishing liquid composition according to any one of ⁇ 1> to ⁇ 10>, wherein the mass ratio A / B between component A and component B is preferably 100 or less, more preferably 90 or less, and still more preferably 80 or less. object.
• the mass ratio A / B between the component A and the component B is preferably 1 or more and 100 or less, more preferably 1.5 or more and 90 or less, and further preferably 2 or more and 80 or less, from ⁇ 1> to ⁇ 11>
• the polishing liquid composition in any one.
• the proportion of component C present in the form of a salt is aqueous at pH 2.
• ⁇ 1> to ⁇ 12> preferably 10% by mass or more, more preferably 20% by mass or more, and still more preferably 30% by mass or more, based on the total amount of component C added to the medium. Polishing liquid composition.
• Component C is dipotassium hydrogen phosphate, disodium hydrogen phosphate, diammonium hydrogen phosphate, potassium dihydrogen phosphate, sodium dihydrogen phosphate, ammonium dihydrogen phosphate, sodium dihydrogen pyrophosphate, pyrroline Polishing liquid composition in any one of ⁇ 1> to ⁇ 13> which is 1 type, or 2 or more types chosen from sodium acid, sodium hexametaphosphate, and sodium tripolyphosphate.
• the content of component C is preferably 0.3% by mass or more, more preferably 0.5% by mass or more, further preferably 0.8% by mass or more, and further preferably 1% by mass or more. ⁇ 1> To ⁇ 14>.
• the content of component C is preferably 10% by mass or less, more preferably 7% by mass or less, further preferably 5% by mass or less, and further preferably 3% by mass or less, any one of ⁇ 1> to ⁇ 15>
• the content of component C is preferably 0.3% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 7% by mass or less, and further preferably 1% by mass or more and 5% by mass or less.
• polishing composition according to any one of ⁇ 1> to ⁇ 16>, wherein the content of component C is 0.8% by mass or more and 3% by mass or less.
• the mass ratio A / C between the component A and the component C is preferably 0.5 or more, more preferably 1 or more, and further preferably 1.5 or more, according to any one of ⁇ 1> to ⁇ 18>.
• Polishing liquid composition ⁇ 20> The polishing liquid composition according to any one of ⁇ 1> to ⁇ 19>, wherein the mass ratio A / C between component A and component C is preferably 26 or less, more preferably 20 or less, and still more preferably 16 or less. object.
• the mass ratio A / C between the component A and the component C is preferably 0.5 or more and 26 or less, more preferably 1 or more and 20 or less, and further preferably 1.5 or more and 16 or less, ⁇ 1> to ⁇ 20 >
• the mass ratio B / C between the component B and the component C is preferably 0.01 or more, more preferably 0.03 or more, still more preferably 0.05 or more, still more preferably 0.07 or more, and 1 or more, The polishing liquid composition in any one of ⁇ 1> to ⁇ 21>.
• the mass ratio B / C between the component B and the component C is preferably 50 or less, more preferably 30 or less, still more preferably 20 or less, still more preferably 10 or less, still more preferably 3 or less, and even more preferably 2 or less.
• the mass ratio B / C between the component B and the component C is preferably 0.01 or more and 50 or less, more preferably 0.01 or more and 30 or less, further preferably 0.03 or more and 20 or less, and 0.05 or more.
• Polishing liquid composition is more preferable, 0.05 or more and 3 or less is more preferable, 0.05 or more and 1 or less is more preferable, and 0.07 or more and 0.4 or less is further preferable, ⁇ 1> to ⁇ 23> Polishing liquid composition.
• ⁇ 27> The polishing composition according to any one of ⁇ 1> to ⁇ 26>, wherein the pH is preferably 0.9 or more, more preferably 1 or more, and still more preferably 1.5 or more.
• ⁇ 28> The polishing composition according to any one of ⁇ 1> to ⁇ 27>, wherein the pH is preferably 6 or less, more preferably 5 or less, and even more preferably 4.5 or less.
• the pH is preferably 0.9 or more and 6 or less, more preferably 1 or more and 5 or less, further preferably 1 or more and 4.5 or less, and further preferably 1.5 or more and 4.5 or less, from ⁇ 1> to ⁇ 28>
• ⁇ 30> The polishing composition according to any one of ⁇ 1> to ⁇ 29>, wherein the glass hard disk substrate is an aluminoborosilicate glass substrate.
• ⁇ 31> A method for producing a glass hard disk substrate, comprising a step of polishing a glass substrate to be polished using the polishing composition according to any one of ⁇ 1> to ⁇ 30>.
• ⁇ 32> A method for polishing a glass substrate, comprising polishing a glass substrate to be polished using the polishing composition according to any one of ⁇ 1> to ⁇ 30>.
• polishing liquid compositions (Examples 1 to 10 and Comparative Examples 1 to 7) Table 1 shows component A (colloidal silica, average particle size 20 nm), component B (sulfamic acid) or non-component B (acid shown in Table 1), component C (phosphate shown in Table 1) and ion-exchanged water.
• the polishing liquid compositions of Examples 1 to 10 and Comparative Examples 1 to 7 were prepared by blending at the stated ratio (mass%) and stirring.
• potassium dihydrogen phosphate component C
• component C potassium dihydrogen phosphate
• the proportion of potassium dihydrogen phosphate present in is 43% by weight, based on the total amount of potassium dihydrogen phosphate added to the aqueous medium at pH.
• Measuring method of various parameters [Measuring method of average particle diameter of silica particles (component A)] A sample containing colloidal silica particles was observed with a transmission electron microscope “JEM-2000FX” (80 kV, 1 to 50,000 times, manufactured by JEOL Ltd.) according to the instructions attached by the manufacturer, and TEM (Transmission Electron) was observed. Microscope) images were taken. This photograph was taken into a personal computer as image data by a scanner, and the equivalent diameter of each silica particle was measured using analysis software “WinROOF ver. 3.6” (distributor: Mitani Corp.) to obtain the particle diameter. . Thus, after calculating
• aluminoborosilicate glass substrate roughly polished in advance with a polishing composition containing ceria abrasive grains was prepared as a substrate to be polished.
• Constituent elements contained in the substrate had a Si content of 24% by mass, an Al content of 8% by mass, and a B content of 1% by mass.
• the constituent elements were measured using the ESCA (Electron Spectroscopy for Chemical Analysis) method under the following measurement conditions.
• polishing Method The substrate to be polished was polished using the polishing liquid compositions of Examples 1 to 10 and Comparative Examples 1 to 7 under the following polishing conditions.
• Polishing tester "Fast double-sided 9B polishing machine” manufactured by Speedfam Polishing pad: Suede type (thickness 0.9mm, average pore diameter 30 ⁇ m, material: urethane foam) Polishing liquid composition supply amount: 100 mL / min (supply rate per 1 cm 2 of polishing substrate: about 0.3 mL / min) Lower platen rotation speed: 24rpm Polishing load: 4.9 kPa Carrier: Aramid, thickness 0.5mm Polishing time: 30 minutes Substrate to be polished: Aluminoborosilicate glass substrate (outer diameter 95 mm, inner diameter 25 mm, thickness 0.65 mm) Number of input substrates: 5
• the polishing liquid compositions of Examples 1 to 10 were deteriorated in the surface roughness of the substrate after cleaning while maintaining the polishing rate as compared with the polishing liquid compositions of Comparative Examples 1 to 7. Was suppressed.
• the polishing composition of the present disclosure According to the polishing composition of the present disclosure, deterioration of the surface roughness of the substrate surface after cleaning can be suppressed while maintaining the polishing rate. Therefore, the polishing composition of the present disclosure is useful in the production of various glass substrates, and is particularly useful in the production of glass substrates for hard disks.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Mechanical Engineering (AREA)
• Materials Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Geochemistry & Mineralogy (AREA)
• Manufacturing Of Magnetic Record Carriers (AREA)
• Surface Treatment Of Glass (AREA)
• Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=68468259

Family Applications (1)

Country Status (3)

Cited By (2)

Citations (4)

• 2018
  • 2018-05-10 JP JP2018091696A patent/JP7158889B2/ja active Active
• 2019
  • 2019-04-23 WO PCT/JP2019/017242 patent/WO2019216205A1/ja not_active Ceased
  • 2019-04-23 MY MYPI2020005860A patent/MY203297A/en unknown

Patent Citations (4)

Also Published As

Similar Documents

Legal Events