公开(公告)号：MY169261A

公开(公告)日：2019-03-20

申请号：MYPI2014702333

申请日：2013-02-28

Applicant: HOYA CORP ,  HOYA CORP

Inventor： TAWARA YOSHIHIRO

Abstract: The present invention provides a method for manufacturing a magnetic-disk glass substrate capable of reducing the number of surface defects such as small scratches, performing polishing processing using abrasive grains without reducing the polishing rate, and manufacturing a high-quality glass substrate that can be used as a next-generation substrate. In the present invention, in a polishing step of polishing main surfaces of a glass substrate (1) containing SiO2 as a main component and a divalent alkali earth metal by holding the glass substrate (1) between a pair of surface plates (5, 6) that have surfaces provided with polishing pads (7) and supplying a polishing liquid containing abrasive grains between the glass substrate (1) and the polishing pads (7), the abrasive grains are made of colloidal silica, and the polishing liquid is adjusted so as to be in an acidic range and contains aluminum ions. (Fig. 1)

公开(公告)号：WO2014163026A8

公开(公告)日：2015-09-03

申请号：PCT/JP2014059379

申请日：2014-03-30

Applicant: HOYA CORP

Inventor： TAWARA YOSHIHIRO

IPC: G11B5/84 ,  B24B37/005 ,  B24B37/11 ,  C03C19/00

CPC classification number: G11B5/8404 ,  B24B37/042 ,  C03C21/002

Abstract: The present invention provides a manufacturing method for magnetic disk glass substrates such that micro-waviness in a range of 50-150 μm in a profile can be reduced. In the present invention, the amount of sinkage into a polishing pad when a circular section of a cylindrical indenter with a diameter of 50 μm is pressed with a load of 2.5 mN from the surface of the polishing pad is measured consecutively on the polishing pad surface in 50 μm intervals at 12 points, and a polishing pad which has a standard deviation of 0.15 μm acquired from data for sinkage amounts for 10 points excluding the largest value and the smallest value of the acquired sinkage amounts is used in the polishing treatment.

Abstract translation: 本发明提供了一种用于磁盘玻璃基板的制造方法，使得可以减小轮廓中的50-150μm范围内的微波纹。 在本发明中，在抛光垫表面上连续地测量直径为50μm的圆柱形压头的圆形部分以2.5mN的载荷被压制在抛光垫中的下沉量， 在12点为50μm间隔，并且在抛光处理中使用从除了最大值和所获得的下沉量的最小值之外的10个点的下沉量的数据获得的具有0.15μm的标准偏差的抛光垫。

公开(公告)号：SG188775A1

公开(公告)日：2013-04-30

申请号：SG2012071700

申请日：2012-09-26

Applicant: HOYA CORP

Inventor： TAMAKI MASANORI ,  NAKAGAWA HIROKI ,  TAWARA YOSHIHIRO

Abstract: MANUFACTURING METHOD OF GLASS SUBSTRATE FOR MAGNETIC DISK, MAGNETIC DISK, AND MAGNETIC DATA RECORDING/REPRODUCING DEVICEA manufacturing method of a glass substrate for a magnetic disk is provided whereby nano pits and/or nano scratches cannot be easily produced in polishing a principal face of a glass substrate using a slurry containing zirconium oxide as an abrasive. The manufacturing method of a glass substrate for a magnetic disk includes, for instance, a polishing step of polishing a principal face of a glass substrate using a slurry containing, as an abrasive, zirconium oxide abrasive grains having monoclinic crystalline structures (M) and tetragonal crystalline structures (T).Fig. 2

公开(公告)号：MY178489A

公开(公告)日：2020-10-14

申请号：MYPI2017700732

申请日：2015-09-14

Applicant: HOYA CORP

Inventor： TAWARA YOSHIHIRO

Abstract: A method for manufacturing a magnetic-disk substrate (1) includes polishing processing in which a substrate (1) is sandwiched between a pair of polishing pads (20), a slurry containing polishing abrasive particles made of a dielectric material is supplied between the polishing pads (20) and the substrate (1), and both main surfaces of the substrate (1) are polished by relatively sliding the polishing pads (20) and the substrate (1). Before the polishing processing, removal processing for removing foreign matter by allowing the slurry to pass through an alternating electric field in which a distribution of electric field intensities caused by shapes of electrodes is non-uniform and separating the foreign matter and the polishing abrasive particles that are present in the slurry by dielectrophoresis is performed.

公开(公告)号：MY163632A

公开(公告)日：2017-10-13

申请号：MYPI2012701270

申请日：2011-08-31

Applicant: HOYA CORP

Inventor： TAWARA YOSHIHIRO ,  HAYAKAWA KIYOSHI ,  OSADA TAIJI

IPC: G11B5/84 ,  B24B7/24

Abstract: THE PRESENT INVENTION PROVIDES A METHOD FOR MANUFACTURING A GLASS SUBSTRATE FOR A MAGNETIC DISK THAT ENABLES GRINDING PROCESSING WITH FIXED ABRASIVE GRAINS WITHOUT A DECREASE OF THE GRINDING RATE AND THAT CAN MANUFACTURE A HIGH QUALITY GLASS SUBSTRATE AT LOW COST. THE PRESENT INVENTION IS A METHOD FOR MANUFACTURING A GLASS SUBSTRATE FOR A MAGNETIC DISK, INCLUDING A GRINDING STEP OF GRINDING A MAIN SURFACE OF A GLASS SUBSTRATE USING A LUBRICANT AND A SURFACE PLATE THAT HAS A GRINDING SURFACE PROVIDED WITH FIXED ABRASIVE GRAINS CONTAINING DIAMOND PARTICLES. IN THE GRINDING STEP, FOR EXAMPLE, BY ADDING AL2O3, AL3+ IS ALLOWED TO BE CONTAINED IN THE LUBRICANT THAT IS SUPPLIED TO THE SURFACE ON WHICH GRINDING PROCESSING IS PERFORMED OF THE GLASS SUBSTRATE. THE LUBRICANT HAS AN AL3+ CONTENT PREFERABLY IN A RANGE OF 0.05 G/L TO 1.0 G/L. (FIG. 2)

公开(公告)号：SG11201701758RA

公开(公告)日：2017-04-27

申请号：SG11201701758R

申请日：2015-09-14

Applicant: HOYA CORP

Inventor： TAWARA YOSHIHIRO

IPC: G11B5/84

Abstract: Provided is a method for manufacture of a substrate for a magnetic disk, comprising a polishing process of sandwiching a substrate with a pair of polishing pads, supplying a slurry which includes a dielectric and abrasive polishing particles between the polishing pads and the substrate, and sliding the polishing pads and the substrate relative to each other, thereby polishing both main surfaces of the substrate. Prior to the polishing process, a removal process is carried out on the abrasive polishing particles of passing the slurry through an alternating electric field with a uniform field strength which arises from electrode shapes, and, with dielectrophoresis, separating foreign matter in the slurry from the abrasive polishing particles, and removing same.

公开(公告)号：SG11201405080XA

公开(公告)日：2014-11-27

申请号：SG11201405080X

申请日：2013-02-28

Applicant: HOYA CORP

Inventor： TAWARA YOSHIHIRO

IPC: G11B5/84 ,  B24B37/00 ,  C03C19/00 ,  C09K3/14

Abstract: Provided is a production method for a glass substrate for a magnetic disk whereby: a high-quality glass substrate can be produced for which surface defects such as minute scratches, etc., can be reduced; polishing using free abrasive grains is possible without an associated drop in the polishing rate; and for which next-generation substrates can be used. Polishing abrasive grains are colloidal silica and a polishing fluid is adjusted to the acidic range and contains aluminum ions, in the polishing step in which: a glass substrate comprising glass having SiO2 as the main component thereof and including a bivalent alkaline rare earth metal is sandwiched by a pair of surface plates having a polishing pad arranged on the surface thereof; and the main surface of the glass substrate is polished by supplying the polishing fluid including the polishing abrasive grains to between the glass substrate and the polishing pads.

公开(公告)号：MY173695A

公开(公告)日：2020-02-17

申请号：MYPI2012700706

申请日：2012-09-27

Applicant: HOYA CORP

Inventor： TAMAKI MASANORI ,  NAKAGAWA HIROKI ,  TAWARA YOSHIHIRO

Abstract: A manufacturing method of a glass substrate (G) for a magnetic disk is provided whereby nano pits and/or nano scratches cannot be easily produced in polishing a principal face of a glass substrate (G) using a slurry containing zirconium oxide as an abrasive. The manufacturing method of a glass substrate (G) for a magnetic disk includes, for instance, a polishing step of polishing a principal face of a glass substrate (G) using a slurry containing, as an abrasive, zirconium oxide abrasive grains having monoclinic crystalline structures (M) and tetragonal crystalline structures (T).

公开(公告)号：SG11201509991QA

公开(公告)日：2016-01-28

申请号：SG11201509991Q

申请日：2014-06-29

Applicant: HOYA CORP

Inventor： TAWARA YOSHIHIRO

IPC: B24B37/00 ,  C09K3/14 ,  C03C19/00 ,  C03C23/00 ,  G11B5/73 ,  G11B5/84

Abstract: The present invention provides a method for manufacturing a glass substrate for a magnetic disk or the like according to which surface roughnesses of main surfaces of a glass substrate can be reduced more than with currently available methods. In the present invention, by mirror-polishing (final finishing-polishing) the main surfaces of the glass substrate used in a magnetic disk, for example, using a polishing liquid containing organic-based particles made of a styrene-based resin, an acrylic resin, or a urethane-based resin, as polishing abrasive particles, surface roughnesses of the main surfaces of the substrate can be reduced more than with currently available methods.

公开(公告)号：SG10201506905SA

公开(公告)日：2015-10-29

申请号：SG10201506905S

申请日：2011-08-31

Applicant: HOYA CORP

Inventor： TAWARA YOSHIHIRO ,  HAYAKAWA KIYOSHI ,  OSADA TAIJI

IPC: G11B5/84 ,  B24B1/00 ,  C10M101/02 ,  C10M101/04 ,  C10M105/14 ,  C10M105/58 ,  C10M105/62 ,  C10M105/70 ,  C10M105/78 ,  C10M107/42 ,  C10M125/10 ,  C10M125/18 ,  C10M125/22 ,  C10M125/24 ,  G11B5/73

Abstract: The present invention provides a method for manufacturing a glass substrate for a magnetic disk that enables grinding processing with fixed abrasive grains without a decrease of the grinding rate and that can manufacture a high quality glass substrate at low cost. The present invention is a method for manufacturing a glass substrate for a magnetic disk, including a grinding step of grinding a main surface of a glass substrate using a lubricant and a surface plate that has a grinding surface provided with fixed abrasive grains containing diamond particles. In the grinding step, for example, by adding Al2O3, Al3+ is allowed to be contained in the lubricant that is supplied to the surface on which grinding processing is performed of the glass substrate. The lubricant has an Al3+ content preferably in a range of 0.05 g/L to 1.0 g/L.