CN106030710B - The manufacturing method of substrate for magnetic disc - Google Patents
The manufacturing method of substrate for magnetic disc Download PDFInfo
- Publication number
- CN106030710B CN106030710B CN201580010429.1A CN201580010429A CN106030710B CN 106030710 B CN106030710 B CN 106030710B CN 201580010429 A CN201580010429 A CN 201580010429A CN 106030710 B CN106030710 B CN 106030710B
- Authority
- CN
- China
- Prior art keywords
- grinding
- magnetic
- substrate
- face
- glass substrate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- 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
- G11B5/8404—Processes or apparatus specially adapted for manufacturing record carriers manufacturing base layers
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
Before carrying out the end surface grinding processing of substrate for magnetic disc, partial size ratio of the partial size of acquirement grinding abrasive grain relative to the partial size of magnetic-particle in advance, the relationship of the ratio between the grinding rate of side wall surface of the fillet surface of substrate relative to substrate when being ground with the magnetic functional fluid using magnetic-particle and grinding abrasive grain with the partial size ratio to the end face of substrate, according to the ratio between the side wall surface of the substrate of the object handled as above-mentioned end surface grinding and the target grinding rate of fillet surface, set the value of above-mentioned partial size ratio, make the magnetic functional fluid of the magnetic-particle and grinding abrasive grain with the value as set partial size ratio.In the processing of above-mentioned end surface grinding, relatively move the end face of the substrate of the object as the processing of above-mentioned end surface grinding in the state of contacting with the block of the above-mentioned magnetic functional fluid formed by magnetic generating unit, so that the end face to substrate is ground.
Description
Technical field
The present invention relates to the manufacturing methods of substrate for magnetic disc, specifically, being related to includes that the end surface grinding of substrate is handled
The manufacturing method of substrate for magnetic disc.
Background technique
Nowadays, personal computer, notebook personal computer or DVD (Digital Versatile Disc,
Digital versatile disc) hard disk device for data record is built-in in recording device etc..Especially counted in notebook type individual
In hard disk device used in the equipment premised on portability such as calculation machine, it is arranged using on the substrate for magnetic disc of nonmagnetic material
Be magnetic the disk of layer.As substrate for magnetic disc, such as use glass substrate.
For the disk, disk generates Spurs (Thermal Asperity) obstacle and regenerates generation mistake in order to prevent
It malfunctions or can not regenerate in order to prevent, it is clean that the surface of disk needs to be polished extremely smooth and foreign height
Net face.
The reason of surface of glass substrate for disc is attached to as foreign matter not only has the surface of the main surface of glass substrate
Shape, it is also contemplated that the surface shape of the end face of glass substrate.That is, if the surface shape of the end face of substrate for magnetic disc is unsmooth,
Then the end face can scrape the wall surface etc. of resin shell, and the particle (particle) of resin or glass is generated due to the scraping.Also,
Particle in this particle or atmosphere can be captured and be accumulated by the end face of glass substrate for disc.At the end of glass substrate for disc
The particle that face is accumulated can become dust generation source in rear process or after being equipped on hard disk device, and foreign matter is caused to be attached to
The surface of optic disc base board.
In general, the end face of glass substrate for disc is ground using abrasive brush and grinding slurry, but in the grinding, grinding
Power is small, processing speed is slow, it is difficult to manufacture glass substrate for disc in large quantities in the short time.On the other hand, it is also known that following methods:
By applying magnetic field to the magnetic slurry comprising magnetic-particle and grinding abrasive grain, to be ground to glass substrate for disc
(patent document 1).
Specifically, in the method ground to magnetic slurry application magnetic field, to as disk glass base
In the process that the inner circumferential end face of the circular hole of the central part of the glass substrate for disc of the raw material of plate is ground, in circular hole
Side forms magnetic field, keeps above-mentioned magnetic slurry using magnetic field in the circular hole, makes magnetic field relative to the inner circumferential side of circular hole
End face is mobile, to keep grinding agent mobile relative to the end face of the inner circumferential side of circular hole, using magnetically grinding method to the inner circumferential of circular hole
It is ground the end face of side.
More specifically, pairs of magnet is set to the outside of glass substrate for disc and the inner circumferential side of circular hole, thus, lead to
Cross the radial direction that pairs of magnet is formed by the magnetic line of force along glass substrate for disc.
Existing technical literature
Patent document
Patent document 1: Japanese Unexamined Patent Publication 2005-50501 bulletin
Summary of the invention
Subject to be solved by the invention
But in the magnetically grinding of above-mentioned glass substrate for disc, in addition to the inner circumferential of the circular hole of glass substrate for disc
It also is also provided with magnet in peripheral side other than side, thus, between magnet set by the inner side end of grinding object and peripheral side
Distance becomes larger, and is unable to fully keep magnetic slurry.As a result, that there are grinding rates is small, can not efficiently reduce grinding object
The problem of surface roughness of inner side end.
In addition, the end face of glass substrate for disc has the side wall surface of glass substrate and is set to the side wall surface and main surface
Between fillet surface.In the case where magnetically grinding method is stated in the end face in use, the side wall surface of glass substrate and fillet surface it
Between grinding rate have differences, not can be implemented simultaneously desired lapping allowance.Therefore, even if the grinding knot of side wall surface
Beam, the grinding of fillet surface is also not finished sometimes, and fillet surface generates grinding residual.In this case, to fillet surface further into
When row grinding, side wall surface is also ground simultaneously, thus the size of side wall surface changes because of grinding, cannot achieve target end face
Shape.In addition, the side wall surface terminated to grinding will do it extra grinding, thus magnetic slurry can be redundantly used, in manufacture
Waste it is more.This problem does not occur only at glass substrate, grinds in the end face of the substrate of nonmagnetic material, such as aluminium alloy substrate
Can similarly it occur in mill.
Therefore, the purpose of the present invention is to provide a kind of manufacturing methods of substrate for magnetic disc, in disks such as glass substrates
With the ratio between the grinding rate that can be adjusted in the end surface grinding processing of substrate between the side wall surface of substrate and fillet surface.
Solution for solving the problem
One embodiment of the present invention is a kind of manufacturing method of substrate for magnetic disc comprising following end surface grinding processing: benefit
It to the side wall surface with disk-shaped substrate and is set to simultaneously with the magnetic functional fluid comprising grinding abrasive grain and magnetic-particle
It is ground the end face of fillet surface between above-mentioned side wall surface and the main surface of aforesaid substrate.In the manufacturing method, at above-mentioned end
Before the milled processed of face, in advance obtain grinding abrasive grain partial size relative to magnetic-particle partial size partial size ratio and using have should
The fillet surface of substrate when the magnetic-particle of partial size ratio and the magnetic functional fluid of grinding abrasive grain grind the end face of substrate
The relationship of the ratio between the grinding rate of side wall surface of the grinding rate relative to substrate, according to the object handled as above-mentioned end surface grinding
Substrate side wall surface and fillet surface between the ratio between target grinding rate, set the value of above-mentioned partial size ratio, production has and becomes
The magnetic-particle of the value of set partial size ratio and the magnetic functional fluid of grinding abrasive grain,
In the processing of above-mentioned end surface grinding,
The block of above-mentioned magnetic functional fluid is formed by magnetic generating unit,
Relatively move the end face of the substrate of the object as end surface grinding processing in the state of with above-mentioned piece of contact, from
And the end face of substrate is ground.
In the processing of above-mentioned end surface grinding, it is preferred that be formed in using magnetic generating unit as end surface grinding processing
The magnetic line of force that the thickness direction of the substrate of object is advanced, is configured at the above-mentioned magnetic line of force for made above-mentioned magnetic functional fluid,
Thus above-mentioned magnetic functional fluid is kept along the above-mentioned magnetic line of force, makes the end face of the substrate of the object as end surface grinding processing
It is relatively moved in the state of being contacted with the above-mentioned magnetic functional fluid kept by the above-mentioned magnetic line of force, thus to the end face of substrate
It is ground.
It is preferred that make above-mentioned end surface grinding handle used in above-mentioned partial size ratio 0.6 in above-mentioned magnetic functional fluid with
Under.
In addition, another way of the invention is also a kind of manufacturing method of substrate for magnetic disc comprising following end surface grindings
Processing: using the magnetic functional fluid comprising grinding abrasive grain and magnetic-particle simultaneously to disk-shaped substrate side wall surface and
It is ground the end face for being set to the fillet surface between above-mentioned side wall surface and the main surface of aforesaid substrate.In the upper of the manufacturing method
It states in end surface grinding processing,
The block of above-mentioned magnetic functional fluid is formed by magnetic generating unit,
Relatively move the end face of the substrate of the object as end surface grinding processing in the state of with above-mentioned piece of contact.This
When, grain of the partial size of grinding abrasive grain relative to magnetic-particle in above-mentioned magnetic functional fluid used in the processing of above-mentioned end surface grinding
The partial size ratio of diameter is 0.6 or less.
In the processing of above-mentioned end surface grinding, it is preferred that be formed in using magnetic generating unit as end surface grinding processing
The magnetic line of force that the thickness direction of the substrate of object is advanced, is configured at the above-mentioned magnetic line of force for made above-mentioned magnetic functional fluid,
Thus above-mentioned magnetic functional fluid is kept along the above-mentioned magnetic line of force, makes the end face of the substrate of the object as end surface grinding processing
It is relatively moved in the state of being contacted with the above-mentioned magnetic functional fluid kept by the above-mentioned magnetic line of force, thus to the end face of substrate
It is ground.
It should be noted that it is preferred that making the above-mentioned grain in above-mentioned magnetic functional fluid used in above-mentioned end surface grinding processing
Diameter ratio is 0.1 or more.
The average grain diameter d50 of above-mentioned grinding abrasive grain is preferably in 0.1 μm~10 μm of range.
The average grain diameter d50 of above-mentioned magnetic-particle is preferably in 0.5 μm~20 μm of range.
Aforesaid substrate at aforesaid substrate and the contact position of above-mentioned magnetic functional fluid is relative to above-mentioned magnetic function stream
The relative velocity of the peripheral speed of body is preferably 50m/ minutes~500m/ minutes.
The effect of invention
According to the manufacturing method of above-mentioned substrate for magnetic disc, can adjust the side wall surfaces of the substrates such as glass substrate for disc with
The ratio between grinding rate between fillet surface.
Detailed description of the invention
(a) of Fig. 1~(c) is illustrated to grinding device used in the processing of the end surface grinding of present embodiment
Figure.
Fig. 2 is to handle the figure being illustrated to the end surface grinding of present embodiment.
Fig. 3 is to show partial size of the grinding abrasive grain relative to magnetic-particle used in the end surface grinding processing of present embodiment
Than the figure of an example of the relationship between the ratio between the grinding rate of fillet surface relative to side wall surface.
Fig. 4 is the lapping allowance progress of measurement to the ratio between grinding rate used in present embodiment in order to obtain
The figure of explanation.
Fig. 5 is the figure for showing an example of the index of the grinding rate of side wall surface of present embodiment.
Fig. 6 is among the processing of the end surface grinding of present embodiment while carrying out the inner circumferential side end face and periphery of glass substrate
The figure that the example of the end surface grinding processing of side end face is illustrated.
Specific embodiment
In the following, the manufacturing method of glass substrate for disc of the invention is described in detail.
Present inventor utilizes the magnetic function comprising grinding abrasive grain and magnetic-particle in the space for generating the magnetic line of force
In the end surface grinding processing that fluid simultaneously grinds side wall surface and fillet surface, various changes are carried out to the condition of the grinding on one side
More, the lapping allowance of side wall surface and fillet surface is investigated on one side, as a result, it has been found that, lapping allowance can be because of grinding abrasive grain and magnetic
The partial size ratio of property particle and change, technology below is contemplated according to the technical idea.
(disk and glass substrate for disc)
The disk of present embodiment is hollowed out concentric circular ring-type in the central part of circular plate type, at the center of ring
Surrounding rotates.The disk at least has disk non-magnetic substrate and magnetosphere.In present embodiment, use glass substrate as
Aluminium alloy substrate also can be used in non-magnetic substrate.It should be noted that other than magnetosphere, such as can also be in glass
Form a film out adhesive layer, soft magnetic layer, nonmagnetic underlayer, perpendicular magnetic recording layer, protective layer and lubricant layer etc. on glass substrate.Adhesive layer
Such as use Cr alloy etc..Adhesive layer is functioned as the adhesive layer with glass substrate.Soft magnetic layer for example using
CoTaZr alloy etc..Nonmagnetic underlayer is for example using granular nonmagnetic layer etc..Perpendicular magnetic recording layer is for example using granular magnetosphere
Deng.Protective layer uses the material formed by hydrogen carbon.Lubricant layer is for example using fluorine resin etc..
Glass substrate used in disk is also in that the central part of circular plate type is hollowed out concentric circular ring-type.Glass base
The inner circumferential side end face of plate and outer peripheral side end face include side wall surface and fillet surface.Side wall surface is in cross-section observation for relative to glass base
The vertically extending face of the main surface of plate.Fillet surface is opposite there are two set between side wall surface and main surface in cross-section observation
In the face that side wall surface is tilted and extended towards main surface with linear or arc-shaped.It should be noted that fillet surface is seen in section
Linear and arc-shaped can have been combined in examining.
The diameter of glass substrate for disc is not particularly limited, glass substrate for example can be used for 1.8 inches of nominal~
The substrate of 3.5 inches of sizes.To plate thickness it is not also specifically limited, for example can be 0.3mm~3mm.
As the material of the glass substrate for disc in present embodiment, can be used alumina silicate glass, soda-lime glass,
Borosilicate glass etc..In particular, from can implement chemical strengthening and can make main surface flatness and substrate it is strong
It sets out in terms of the excellent glass substrate for disc of degree aspect, alumina silicate glass can be properly used.
The composition of the glass substrate of present embodiment is not limited, as alumina silicate glass, it is preferable to use by following
It forms the alumina silicate glass constituted: being converted with oxide benchmark, indicated with a mole %, with 50%~75%
SiO2；It more than 0% and is 15% Al below2O3；Add up to 12%~35% selected from Li2O、Na2O and K2At least one in O
Kind ingredient；Add up to 0%~20% selected from least one of MgO, CaO, SrO, BaO and ZnO ingredient；And it adds up to
0%~10% be selected from ZrO2、TiO2、La2O3、Y2O3、Ta2O5、Nb2O5And HfO2At least one of ingredient.
In addition, the glass substrate of present embodiment for example can also be as disclosed in Japanese Unexamined Patent Publication 2009-99239 bulletin
Like that, it is the unbodied alumina silicate glass of composition consisting of the following: in terms of indicating by quality %, has 57%~75%
SiO2；5%~20% Al2O3(wherein SiO2With Al2O3Total amount be 74% or more)；It is total more than 0% and below for 6%
ZrO2、HfO2、Nb2O5、Ta2O5、La2O3、Y2O3And TiO2；It more than 1% and is 9% Li below2O；5%~18% Na2O
(wherein mass ratio Li2O/Na2O is 0.5 or less)；0%~6% K2O；0%~4% MgO；It more than 0% and is 5% or less
CaO (wherein, the total amount of MgO and CaO be 5% hereinafter, and CaO content be more than MgO content)；0%~3% SrO+
BaO。
(end surface grinding processing)
(a) of Fig. 1~(c) is the end face to a processing in the manufacturing method as the glass substrate of present embodiment
The figure that device used in milled processed is illustrated, Fig. 2 are to handle the figure being illustrated to the end surface grinding of present embodiment.
The grinding of the inner circumferential side end face for illustrating glass substrate of Fig. 2.About end surface grinding, the outer peripheral side end face of glass substrate
Grinding can also be applicable in by identical method.
In end surface grinding processing, the block of aftermentioned magnetic functional fluid is formed by magnetic generating unit, is made as end face
The end face of the substrate of the object of milled processed relatively moves in the state of with above-mentioned piece of contact, so that the end face to substrate carries out
Grinding.
At this point, being formed in the thickness direction traveling as the substrate of the object of end surface grinding processing using magnetic generating unit
Made magnetic functional fluid is configured at the magnetic line of force, thus keeps magnetic functional fluid along the magnetic line of force by the magnetic line of force,
Make the end face of the substrate of the object as end surface grinding processing in the shape contacted with the magnetic functional fluid kept by the magnetic line of force
It is relatively moved under state, so that the end face to substrate is ground.
The summary for the device 10 for carrying out end surface grinding is illustrated, as shown in (a) of Fig. 1, device 10 includes as forever
A pair of magnet 12,14 and spacer 16 of long magnet, in the rotary body shape extended in one direction.In magnet 12 and magnet
Spacer 16 is equipped between 14.The glass substrate 11 for carrying out end surface grinding is kept by holding tool (not shown).Make device 10
The circular hole for running through the glass substrate 11 that the tool of being kept is kept makes aftermentioned to include magnetic-particle and grinding abrasive grain
The block 20 ((c) referring to Fig.1, Fig. 2) of magnetic functional fluid is contacted with the inner circumferential side end face of glass substrate 11.Magnetic functional fluid
Become the block 20 of circular ring shape around device 10.At this point, according to the central axis of glass substrate 11 and the magnet 12,14 of device 10
Glass substrate 11 is configured with the same directional mode of central axis of spacer 16.Device 10 and glass substrate 11 are distinguished
The holding tool (not shown) kept and drive motor (not shown) are mechanically connected.The device 10 and glass of rotary body shape
The holding tool of substrate 11 rotates around respective central axis, relatively moves the end face of glass substrate 11 and block 20.Such as
Shown in Fig. 2, the end face of glass substrate 11 and the direction of rotation of block 20 can be the same direction, or opposite direction.As a result,
Can the inner circumferential side end face to glass substrate 11 grind.It should be noted that exterior member can be set also to cover magnetic
Iron 12,14 and spacer 16.In the illustrated example shown in fig. 2, the central axis of the central axis of glass substrate 11 and device 10 is biased,
But the central axis of glass substrate 11 can also be consistent with the central axis of device 10.
When grinding to the inner circumferential side end face of glass substrate 11, pass through the rotation around the central axis of device 10, magnetic
The block 20 of functional fluid is rotated, and on the other hand, glass substrate 11 is also rotated around central axis.At this point, in order to
Efficiently carry out end surface grinding, the phase of glass substrate 11 and the glass substrate 11 at the contact position of the block 20 of magnetic functional fluid
Relative velocity for the peripheral speed of the block 20 of magnetic functional fluid is preferably 50m/ minutes~500m/ minutes, above-mentioned opposite
Speed is more preferably 200m/ minutes~400m/ minutes.It should be noted that the inner circumferential side end face of glass substrate 11 can also be made
Whole circumference contacted with the whole circumference of block 20 and make its rotation.The block 20 of magnetic functional fluid is formed as circular ring shape, thus,
Can not make the shape distortion of circular hole and to the inner circumferential side end face of the inner wall of the circular through hole as glass substrate 11 into
Row grinding.In this case, the revolving speed of preferably glass substrate 11 is, for example, 500rpm~4000rpm, and the revolving speed of block 20 is, for example,
50rpm~300rpm.It should be noted that as described later, the case where the outer peripheral side end face to glass substrate 11 is ground
Under, it is also preferred that the revolving speed of glass substrate 11 is, for example, 500rpm~4000rpm, the revolving speed of block 20 is, for example, 50rpm~300rpm.
Revolving speed in this way, can be carried out efficiently end surface grinding.
From efficiently progress end surface grinding processing aspect, the direction of rotation of glass substrate 11 and the rotation side of block 20
It is opposite direction to the contact position preferably in glass substrate 11 and block 20.On the other hand, from end surface grinding is reduced, treated
From the aspect of the concave-convex surface of end face, the direction of rotation of glass substrate 11 and the direction of rotation of block 20 are in glass substrate 11 and block
20 contact position is preferably the same direction.
As long as can not also be rotated it should be noted that the end face of glass substrate 11 and block 20 can be made to relatively move
Block 20 and rotary glass substrate 11.
End surface grinding is more specifically illustrated, magnet 12 and magnet 14 are close to each other to send out as magnetic generating unit
Function is waved, the magnetic line of force 19 shown in (b) of Fig. 1 are formed.A part of the magnetic line of force 19 is from the center of magnet 12,14 with linear
It advances, advances in the thickness direction of glass substrate 11.In addition, a part of the magnetic line of force 19 according to from the center of magnet 12,14 to
Outside mode outstanding is advanced, and is advanced in the thickness direction of glass substrate 11.In the example shown in (b) of Fig. 1, in glass
The thickness direction of glass substrate 11, the magnet in the face in face and the pole S with state that is mutually opposed and separating configured with the pole N is to being used as
Magnetic generating unit.Face is mutually opposed to refer to that face and face be opposite in parallel, i.e. face.In order to make magnet 12 the pole N end face and magnetic
Spacing distance between the end face of the pole S of iron 14 is predetermined distance, is equipped between magnet 12,14 by nonmagnetic material structure
At spacer 16.Keep the spacing distance between the end face of the pole N of magnet 12 and the end face of the pole S of magnet 14 predetermined
Distance be because are as follows: in addition to making concavity of a part of the magnetic line of force 19 as shown in (b) of Fig. 1 between magnet 12 and magnet 14
Other than lower section in from slot to figure is advanced, also make a part of the magnetic line of force 19 prominent to the outside of magnet 12 and magnet 14, thus
The block 20 of magnetic functional fluid shown in (c) of Fig. 1 is made along the periphery of device 10.Block 20 is the end with glass substrate 11
Face contact, the part that relative motion is carried out between the end face, therefore from the aspect of the rigidity for ensuring block 20, it is desirable to magnetic
Power is stronger.It is therefore preferable that the spacing distance between the end face of the pole S of the end face and magnet 14 of the pole N of magnet 12 is short, but interval distance
In the case where too short, it is unable to fully to form block 20.Therefore, between the end face of the pole S of the end face and magnet 14 of the pole N of magnet 12
Spacing distance be defined as some particular range.
In the end surface grinding of the glass substrate of present embodiment, from raising grinding rate aspect, preferably glass
The end face of substrate 11 is extruded in the inside of block 20 in the direction orthogonal with the magnetic line of force, to be ground.By with the magnetic line of force
Orthogonal direction is squeezed, and by the high resistance from block 20, grinding is promoted for the end face of glass substrate 11.
The end face of the glass substrate 11 of present embodiment is according to the connection magnet 12 inside the block 20 with magnetic functional fluid
The pole N and magnet 14 the pole S the magnetic line of force, the i.e. magnetic line of force from the pole N or from the extension of the pole S and the magnetic force that terminates in the pole S or the pole N
The mode for the part contact that line is kept is extruded into the inside of block 20.Along the pole N and the pole S of magnet 14 of connection magnet 12
The part for the magnetic functional fluid that the magnetic line of force is kept compared with the magnetic line of force is in the unclosed part of magnetic pole rigidity improve, it can be achieved that
High grinding rate.On the other hand, the main surface of glass substrate 11 and major part are interdicted by glass substrate 11 and are not reached magnetic pole
The part of the low block 20 of the rigidity that the magnetic line of force is kept contacts, thus, even if block 20 is contacted with the main surface of glass substrate 11,
It is not ground substantially.
Block 20 is formed in the outer peripheral surface of spacer 16 as groove bottom and using the end face of magnet 12 and magnet 14 as side
In the concave slot of wall surface, the end face of glass substrate can be squeezed in the block 20 to the slot, but can also be such as (c) of Fig. 1
Shown the recess portion between magnet 12 and magnet 14 is prominent like that, and the end face of glass substrate is squeezed to the protruding portion.
Glass substrate 11 is squeezed into in such a way that side wall surface and fillet surface are ground simultaneously the inside of block 20 as described above,
But the part contacted with block 20 in the main surface of glass substrate is not ground substantially at this time.
It should be noted that having used permanent magnet to produce as magnetic in (a)~(c) of Fig. 1 and example shown in Fig. 2
Raw unit, but electromagnet also can be used.In addition, in order to will be between the end face of the pole N of magnet 12 and the end face of the pole S of magnet 14
Spacing distance be ensured to be a certain distance, used spacer 16, however, you can also not use spacer 16, and make magnet 12,
14 is fixed thus by the interval between the end face of the pole N of magnet 12 and the end face of the pole S of magnet 14 by exterior member (not shown)
Distance ensures centainly.
Magnetic functional fluid used in end surface grinding is for example using comprising containing 3g/cm3~5g/cm3The magnetic formed by Fe
The property non-polar oil of particle and the magneto-rheological fluid of surfactant.In this specification, wrapped in the magneto-rheological fluid by making
Containing grinding abrasive grain, to form magnetic functional fluid.Non-polar oil or polar oil have 100 for example under room temperature (20 DEG C)~
The viscosity of 1000 (mPa seconds).As described later, from grinding rate the ratio between of the fillet surface relative to side wall surface can be suitably adjusted
Aspect set out, the average grain diameter d50 (diameter) of magnetic-particle is preferably 2.0 μm~7.0 μm.Average grain diameter d50 is partial size point
The intermediate value of cloth.
For the block 20 formed by magnetic functional fluid, in magnetic functional fluid on the magnetic line of force shape in a manner of block
Cheng Shi, grinding abrasive grain are also contained in block 20 in the same manner as magnetic-particle.Grinding abrasive grain in magnetic functional fluid is because of magnetcisuspension
It floats effect and is extruded to the low part of magnetic gradient, therefore concentrate and be present near the end face to be ground of glass substrate.
Moreover, the block with relatively high elastic characteristic is formed by the magnetic line of force, thus by squeezing the end face of glass substrate
To block 20, grinding can be carried out efficiently.That is, can be improved grinding rate, grinding can be carried out efficiently.
As the grinding abrasive grain for including in magnetic functional fluid, can be used cerium oxide, colloidal silicon dioxide, zirconium oxide,
The grinding abrasive grain of glass substrate well known to alumina abrasive grain, diamond abrasive grain, silica abrasive grain, SiC abrasive grain etc..About grinding
The partial size of abrasive grain, from can suitably adjust the ratio between the grinding rate of fillet surface relative to side wall surface, height can be efficiently obtained
It sets out in terms of the surface of quality, for example, 0.4 μm~3.0 μm.By using the grinding abrasive grain of the range, can grind well
The inner circumferential side end face of ground glass substrate.Grinding abrasive grain in magnetic functional fluid for example comprising 3 volume of volume %~15 %.It needs
It is noted that grinding rate is with lapping allowance divided by value obtained from milling time, thus if identical grinding
Time, then the ratio between the ratio between grinding rate and lapping allowance are identical value, and meaning is identical.Therefore, in this case, adjustment grinding
The ratio between rate may be the ratio between adjustment lapping allowance.
From forming block 20, efficiently carrying out end surface grinding aspect, preferably adjusted by the concentration of magneto-rheological fluid
Making the viscosity for the magnetic functional fluid that magneto-rheological fluid is utilized is 1000~2000 [mPa seconds] under room temperature (20 DEG C).It is viscous
When spending low (concentration of magneto-rheological fluid is low), it is difficult to form block 20, it is difficult in the state of extruding to the end face of glass substrate 11
It carries out relative motion and is ground.On the other hand, in the case that the viscosity of magnetic functional fluid is excessively high, the shape in grinding of block 20
The shape being recessed at the end shape along glass substrate 11, it is difficult to which, by the recovery of shape, block 20 remains glass base strongly
The shape of plate 11, therefore, it is difficult to form uniform squeezed state.In addition, from formed block 20, efficiently carry out end surface grinding side
Face is set out, and the magnetic flux density in magnetic generating unit is preferably 0.3~2 [tesla].In addition, in the magnetic for applying 0.4 [tesla]
In the state of, the yield stress of magneto-rheological fluid is preferably 30kPa or more, more preferably 30kPa~60kPa.
In present embodiment, before the processing of such end surface grinding, the partial size of grinding abrasive grain is obtained in advance relative to magnetic
Property particle partial size partial size than with using with the partial size ratio magnetic-particle and grinding abrasive grain magnetic functional fluid carry out
Grinding rate of the grinding rate of the fillet surface of glass substrate 11 relative to the side wall surface of glass substrate 11 when end surface grinding processing
The ratio between relationship.In addition, setting above-mentioned partial size according to the ratio between the side wall surface of glass substrate 11 and the target grinding rate of fillet surface
The value of ratio makes the magnetic functional fluid of the magnetic-particle and grinding abrasive grain with the value as set partial size ratio.Production
Such magnetic functional fluid is because it is found that following phenomenons: in partial size ratio and chamfering of the grinding abrasive grain relative to magnetic-particle
There are correlativities between the ratio between the grinding rate of face relative to side wall surface, and as described later, above-mentioned partial size is than smaller, then above-mentioned to grind
It is higher to grind the ratio between rate.
Fig. 3 be grinding abrasive grain is shown relative to magnetic-particle partial size than the grinding rate with fillet surface relative to side wall surface
The ratio between grinding rate between relationship an example figure.In the example depicted in fig. 3, the average grain diameter of magnetic-particle has been used
D50 (diameter) is 2 μm, 4 μm, the magnetic-particle that is formed of 7 μm of Fe, has used zirconia grain as grinding abrasive grain.At this point, logical
It crosses and the average grain diameter d50 (diameter) of grinding abrasive grain is made various changes, so that above-mentioned partial size ratio be made to make various changes.
It should be noted that in order to find out the grinding rate of the grinding rate of side wall surface and fillet surface, as shown in figure 4, sharp
The section shape of the side wall surface 11a and fillet surface 11b of end face are determined before and after end surface grinding processing with contour shape measuring instrument
Shape.Central portion and the side in the face along fillet surface 11b in the plate thickness direction of side wall surface 11a are obtained according to the cross sectional shape measured
To central portion lapping allowance P1、P2, so as to find out the ratio between grinding rate.It should be noted that Fig. 4 is added to grinding
Spare time measures the figure being illustrated.
From the figure 3, it may be seen that the average grain diameter d50 (diameter) of magnetic-particle be 2 μm, 4 μm, under 7 μm of either case, it is aobvious
Roughly the same correlativity is shown.By the correlativity it is found that by reduce partial size ratio (reduce grinding abrasive grain partial size or
The partial size of person's increase magnetic-particle), fillet surface 11b can be made to improve relative to the ratio between grinding rate of side wall surface 11a.Therefore,
In the case where fillet surface 11b occurs to grind remaining situation, by reducing the average grain diameter d50 (diameter) of grinding abrasive grain or increasing
The partial size of magnetic-particle can make side wall surface 11a roughly the same with the grinding rate of fillet surface 11b, can not grind residual
It stays and is ground.
In this way, the average grain diameter d50 (diameter) using the average grain diameter d50 (diameter) of grinding abrasive grain relative to magnetic-particle
The ratio between, it can determine the ratio between grinding rate.It follows that passing through the flat of any one in variation magnetic-particle and grinding abrasive grain
Equal partial size d50 (diameter) adjusts partial size ratio, so as to adjust the grinding rate between side wall surface 11a and fillet surface 11b it
Than.
It is confirmed in the case where 0.1 μm~10 μm of range in the average grain diameter d50 (diameter) of grinding abrasive grain such
Correlativity.In addition, being confirmed in the case where 0.5 μm~20 μm of range in the average grain diameter d50 (diameter) of magnetic-particle
Such correlativity.Wherein, from can realize the ratio between target grinding rate with preferably precision, Gao Pin can be efficiently obtained
From the aspect of the surface of matter, the preferably average grain diameter d50 (diameter) of grinding abrasive grain is 0.4 μm~3.0 μm；From can be with more preferable
Ground precision is realized the ratio between target grinding rate, can be efficiently obtained from the aspect of the surface of high-quality, preferably magnetic-particle
Average grain diameter d50 (diameter) be 2.0 μm~7.0 μm.
The production principle of this relationship is not clear, but is presumed as follows.That is, as shown in (c) of Fig. 1, magnetic functional fluid
In the state of block 20, the magnetic-particle in magnetic functional fluid forms the line of the magnetic-particle arranged along the magnetic line of force, block
20 have high rigidity.At this point, being dispersed with grinding abrasive grain around magnetic-particle.If the end of glass substrate 11 in this state
Face enters the inside of block 20, then block 20 occurs flexible deformation and makes change in shape.On the other hand, due to the high rigidity of block 20, glass
The end face of glass substrate 11 can be squeezed to block 20, due to relatively fast between the extruding force and block 20 and the end face of glass substrate 11
Degree, the end face of glass substrate 11 are slided relative to block 20, and end face is ground.At this point, due to the shape distortion of block 20, grinding mill
The the partial size of grain the big, and the power of the above-mentioned line of magnetic-particle to be got into is bigger, thus above-mentioned line is easy cutting.
Herein, since the end face of glass substrate 11 enters in block 20, thus the line of the magnetic-particle in block 20 is along by side
The shape for the end face that wall surface 11a and fillet surface 11b are constituted is deformed with paddy shape recess, block 20 towards the end face of glass substrate 11 and
Generate resistance.At this point, the region of the line of the magnetic-particle near the side wall surface 11a being located in the block 20 of deformation from magnetic
Power of the orthogonal direction in the direction of the extension of the line of grain by side wall surface 11a, in contrast, near fillet surface 11b
The region of the line of magnetic-particle is deformed into the sloping portion of the line of paddy shape, thus the side entered along glass substrate 11 due to being located at
To extension.Power of the sloping portion of the line from the direction that glass substrate 11 is entered by glass substrate 11.In particular, being located to fall
The sloping portion of line near edged surface 11b, if large-sized grinding abrasive grain gets into line, from glass substrate 11 by towards glass
The power of the approach axis of substrate 11, the distance between magnetic-particle on above-mentioned line is elongated, thus above-mentioned line become easy it is cut-off.
Therefore, the magnetic functional fluid in the region is unable to maintain that high rigidity, thus the grinding abrasive grain supported by the line of magnetic-particle
Power provided by fillet surface 11b is reduced.Therefore, the grinding rate of fillet surface 11b is easily reduced compared with side wall surface 11a.Separately
On the one hand, it in the case where the partial size of grinding abrasive grain is small, is intended to get into the grinding of the line of the magnetic-particle near fillet surface 11b
The power of abrasive grain is weak, thus is difficult to happen the cutting of line.
Even if the partial size of grinding abrasive grain is certain, change of size of magnetic-particle in the case where, it may also be said to be above-mentioned feelings
Condition.Therefore, if increasing partial size ratio of the grinding abrasive grain relative to magnetic-particle, grinding of the fillet surface 11b relative to side wall surface 11a
The ratio between rate reduces, if reducing partial size ratio, the ratio between the grinding rate of fillet surface 11b relative to side wall surface 11a is improved, and approaches
1.0。
Carry out end surface grinding treated side wall surface 11a's and fillet surface 11b about using such magnetic functional fluid
Surface roughness, maximum height Rz (JIS B0601:2001) is preferably 0.15 μm or less.As a result, in side wall surface 11a and chamfering
The depth shallower for the small slot that face 11b is generated, thus a possibility that particle attachment, is reduced.In addition, treated for end surface grinding
The arithmetic average roughness Ra (JIS B0601:2001) of side wall surface 11a and fillet surface 11b is preferably 0.015 μm or less.
Such surface roughness be using laser microscope 50 μm of square evaluation region, under the following conditions measure
When maximum height Rz and arithmetic average roughness Ra.At this point, the resolution ratio of short transverse is preferably 1nm or less.In addition, observation
Multiplying power is suitable for selection in the range of 1000 times~3000 times or so according to the size of aspect of measure.
Observation multiplying power: 3000 times,
The measurement spacing of short transverse (Z axis): 0.01 μm,
Cutoff value λ s:0.25 μm,
Cutoff value λ c:80 μm.
It should be noted that if reducing partial size ratio, then grinding rate the ratio between of the fillet surface 11b relative to side wall surface 11a mentions
Height, but the partial size of grinding abrasive grain becomes smaller, thus abrasive power reduces, the value itself of grinding rate reduces.Fig. 5 is to show side wall surface
The figure of an example of the index of the grinding rate of 11a.In the example depicted in fig. 5, make the average grain diameter d50 (diameter) of magnetic-particle
2 μm are fixed as, various change is carried out to the partial size of the average grain diameter d50 (diameter) of grinding abrasive grain.The index of above-mentioned grinding rate
Be by partial size than 1.2 under the conditions of grinding rate be set as 1.00 and standardized index (the more high then grinding rate of index is higher).
As shown in Figure 5, partial size is lower than smaller then grinding rate.Therefore, the place in order not to handle the end surface grinding of glass substrate 11
Managing the time is that for a long time, partial size is than preferably 0.1 or more, more preferably 0.2 or more.
It should be noted that side wall surface 11a and fillet surface 11b pass through with grinding mill in the manufacturing process of glass substrate
Stone mill is cut the shape processing of the end face of glass substrate and is formed.Side wall surface 11a and fillet surface 11b are formed by by the grinding grinding stone
Surface roughness be in many cases same degree.Therefore, the side wall surface 11a and fillet surface 11b in end surface grinding processing
Required lapping allowance is roughly the same in many cases.Therefore, in this case, in end surface grinding processing, preferably
The grinding rate of side wall surface 11a and fillet surface 11b are roughly the same.From this side considerations, preferably make side wall surface 11a and fillet surface
The ratio between grinding rate of 11b is 0.8 or more, more preferably 0.9 or more.If making the ratio between grinding rate less than 0.8, fillet surface
The grinding rate of 11b becomes extremely low compared with the grinding rate of side wall surface 11a, if the lapping allowance of cooperation side wall surface 11a
And terminate end face milled processed, then fillet surface can generate grinding residual sometimes, the surface roughness of fillet surface relative to target compared with
It is coarse.On the other hand, for end surface grinding processing, if cooperating the lapping allowance of fillet surface and terminating at end surface grinding
Reason, then the time to required for terminating is long, and productivity reduces.Therefore, in order to realize the ratio between above-mentioned preferred grinding rate, preferably
Grain of the grinding abrasive grain relative to magnetic-particle is determined using the ratio between above-mentioned preferred grinding rate and correlativity shown in Fig. 3
Diameter ratio.
In order to make the ratio between above-mentioned grinding rate be 0.8 or more, correlativity according to Fig.3, partial size ratio be 0.6 with
Under.Therefore, in a mode of present embodiment, relative to magnetism in magnetic functional fluid used in end surface grinding processing
The partial size ratio of the grinding abrasive grain of the partial size of particle is 0.6 or less.At this point, the grinding rate of side wall surface 11a is never greatly reduced
From the aspect of, above-mentioned partial size is than preferably 0.1 or more, more preferably 0.2 or more.That is, by making partial size ratio 0.1 or more 0.6
It below, and then is 0.2 or more 0.6 hereinafter, substantially the grinding of side wall surface 11a and fillet surface 11b can be terminated simultaneously, and grind
Time is not elongated, can be carried out efficiently the end surface grinding processing of glass substrate 11.
It should be noted that just having carried out gestalt shape according to the mode of the shape processing of side wall surface 11a and fillet surface 11b and having added
The surface roughness of side wall surface 11a and fillet surface 11b after work generate difference sometimes.In this case, side wall surface 11a and fall
The lapping allowance of edged surface 11b is also different.Therefore, can be determined according to different lapping allowances grinding rate it
Than determining partial size ratio using correlativity shown in Fig. 3.As a result, in the attrition process for making side wall surface 11a and fillet surface 11b
Surplus is different and in the case where carrying out end surface grinding, by adjusting the ratio between grinding rate, the grinding of side wall surface 11a can be made to terminate
Moment and the grinding finish time of fillet surface 11b are unified.
End surface grinding described above processing is the end surface grinding processing of the inner circumferential side end face of glass substrate 11, but can also be with
The end surface grinding of outer peripheral side end face suitable for glass substrate 11 is handled.
Fig. 6 be to and meanwhile carry out glass substrate 11 inner circumferential side end face and outer peripheral side end face end surface grinding processing example
The figure being illustrated.
In the example depicted in fig. 6, the inner circumferential side end face of glass substrate 11 is ground, and at the same time to glass substrate
11 outer peripheral side end face is ground.That is, the device for being formed with block 20 10 is made to run through the center for being set to glass substrate 11
Circular through hole contacts the block 20 of magnetic functional fluid with the inner circumferential side end face of glass substrate 11.Meanwhile magnet 12,
The surface of the periphery of spacer (not shown) between 14 and magnet same as spacer 16 60,64 forms magnetic functional fluid
Block 62.The position of magnet 60,64 and spacer (not shown) is determined in the way of contacting by block 62 with glass substrate 11.Magnetic
Iron 60,64 and spacer (not shown) are mechanically connected in the same manner as magnet 12,14 and spacer 16 with drive motor (not shown),
It can rotate.Therefore, make to include the device 10 of magnet 12,14 and spacer 16 and including magnet 60,64 and interval (not shown)
The device of object rotates in the direction different from glass substrate 11, and thus, it is possible to simultaneously to the inner circumferential side end face of glass substrate 11 and outer
All side end faces are ground, and can be realized efficient end surface grinding.It should be noted that showing in the example depicted in fig. 6
Following situations: the central axis of the rotary shaft as glass substrate 11 is relative to the rotary shaft as magnet 12,14 and spacer 16
Central axis biasing, only a part of the inner circumferential side end face of glass substrate 11 is contacted with block 20, progress end surface grinding.Certainly, make
Central axis for the rotary shaft of glass substrate 11 can also be with the central axis one as magnet 12,14 and the rotary shaft of spacer 16
It causes, the inner circumferential end face of glass substrate 11 is whole uniform and is ground simultaneously.
It, can also be by multiple glass substrates along the device including magnet and spacer about the processing of such end surface grinding
It is central axial arranged, and then form multiple pieces 20,62 in the periphery of device, make each piece 20,62 and different glass
Substrate abuts, to grind simultaneously to the end face of multiple glass substrates.
Main surface of the side wall surface 11a of present embodiment in cross-section observation relative to glass substrate extends vertically,
Edged surface 11b is tilted and towards main surface relative to side wall surface linearly to extend in cross-section observation, but side wall surface 11a and chamfering
Face 11b can also be formed as arc-shaped in cross-section observation.
It should be noted that being carried out in present embodiment to the mode for the end surface grinding processing for carrying out a piece of glass substrate
Explanation, but can also be handled by end surface grinding simultaneously to main surface to be pasted to substrate made of lamination two panels or more each other
It is ground the end face of each laminated substrate of laminate.In this case, the main surface of laminated substrate can use bonding agent, example
Such as heat-curing resin is pasted and substrate laminate is made.The productivity of substrate improves as a result,.
Above end surface grinding processing is carried out as a processing of the manufacturing method of glass substrate described below.
(manufacturing method of glass substrate)
Then, the manufacturing method of the glass substrate for disc of present embodiment is illustrated.Firstly, passing through compression molding
Make the glass blank (compression molding processing) of the raw material of the glass substrate for disc as the plate with a pair of of main surface.
It should be noted that glass blank is made in present embodiment by being pressed and molded, but can also using well known float glass process, again
Daraf(reciprocal of farad) or fusion method form glass plate, are cut into the glass blank with above-mentioned glass blank same shape from glass plate.It connects
, circular hole is formed in the central part of made glass blank, the glass substrate of annular (annular shape) is made (at circular hole formation
Reason).Then, shape processing (shape processing processing) is carried out to the round-meshed glass substrate of formation.Glass substrate is consequently formed.It connects
, end surface grinding (end surface grinding processing) is carried out for the glass substrate through shape processing.To the glass for carrying out end surface grinding
The main surface of substrate is ground (grinding processing).Then, the 1st grinding is carried out (at the 1st grinding to the main surface of glass substrate
Reason).Then, chemical strengthening (chemical intensification treatment) is carried out to glass substrate as needed.Then, the 2nd is carried out to glass substrate
It grinds (the 2nd milled processed).Thereafter, ultrasonic cleaning is carried out (at ultrasonic cleaning to the glass substrate after the 2nd milled processed
Reason).By above processing, glass substrate for disc is obtained.Hereinafter, each processing is described in detail.
(a) compression molding is handled
The front end of melten glass stream is cut off using cutting machine, the fused glass block of cutting is sandwiched into a pair of of metal die
Compression molding face between, be molded, glass blank formed.After the molding for carrying out the stipulated time, metal die is opened, is taken
Glass blank out.
(b) circular hole formation is handled
For glass blank, circular hole is formed using boring etc., thus the also glass base of the available plate-like for being provided with round hole
Plate.
(c) shape processing is handled
In shape processing processing, the end face for forming treated glass substrate for circular hole carries out chamfer machining.Chamfering
Processing is carried out using grinding grinding stone etc..By chamfer machining, following end faces, the end face tool are formed in the end face of glass substrate
There is the side wall surface of the vertically extending substrate of main surface relative to glass substrate and is set between the side wall surface and main surface simultaneously
The fillet surface obliquely extended with side wall surface.
(d) end surface grinding is handled
In end surface grinding processing, for the inner side end and outer peripheral side end face of glass substrate, above-mentioned magnetic function is utilized
Property fluid by end surface grinding shown in FIG. 1 processing mirror-finished.At this point, in magnetic functional fluid, in addition to magnetic
Other than grain, also comprising grinding abrasive grains such as cerium oxide, zirconium oxide, silica, diamonds.It should be noted that end can be replaced
The processing sequence of face milled processed and following grinding processing.
(e) grinding is handled
In grinding processing, carried out using main surface of the double-sided grinding device for having planetary gear mechanism to glass substrate
Grinding.Specifically, be on one side maintained at glass substrate in the retaining hole for being set to the holding member of double-sided grinding device,
The main surface of the two sides of glass substrate is ground on one side.Double-sided grinding device has upper and lower a pair of of price fixing, and (upper fixed disk is under
Price fixing), glass substrate is clamped between the upper plate and the lower plate.Also, by making any one in upper fixed disk or lower fixed disk
Or both carry out moving operation, relatively move glass substrate and each price fixing, it is possible thereby to two main surfaces of glass substrate into
Row grinding.
(f) the 1st milled processed
Then, the 1st grinding is implemented to the main surface of the glass substrate of grinding.Specifically, glass substrate is kept on one side
In the retaining hole of grinding carrier for being set to double-side polishing apparatus, the main surface of the two sides of glass substrate is ground on one side
Mill.The purpose of 1st grinding is to remove the remaining scar of grinding treated main surface institute or deformation, or to small surface
Concave-convex (micro-waviness, roughness) is adjusted.
It is same using having with double-sided grinding device used in the grinding processing using fixed abrasive grain in 1st milled processed
The double-side polishing apparatus that sample is constituted, is directed at glass substrate while providing grinding slurry and grinds.In 1st milled processed, make
With the grinding slurry comprising free abrasive grain.As free abrasive grain used in the 1st grinding, such as use cerium oxide abrasive grain or oxygen
Change zirconium abrasive grain etc..Double-side polishing apparatus also clamps glass substrate between upper and lower a pair of of price fixing in the same manner as double-sided grinding device.
Grinding pad (such as the resin finish material of the generally plate of circular ring shape is installed in the upper surface of lower fixed disk and the bottom surface of upper fixed disk
Material).Also, by make in upper fixed disk or lower fixed disk any one or both moving operation, to make glass substrate and Ge Ding
Disk relative movement, thus grinds two main surfaces of glass substrate.
(g) chemical intensification treatment
In the case where carrying out chemical strengthening to glass substrate, as chemical strengthening liquid, such as potassium nitrate and sodium sulphate are used
Mixed melting liquid etc., glass substrate is impregnated in chemical strengthening liquid.
(h) the 2nd grinding (final grinding) processing
Then, the 2nd grinding is implemented to glass substrate.The purpose of 2nd milled processed is the mirror ultrafinish of main surface.?
In 2 grindings, also using has the double-side polishing apparatus equally constituted with double-side polishing apparatus used in the 1st grinding.Specifically
It says, is on one side maintained at the outer peripheral side end face of glass substrate in the retaining hole for the grinding carrier for being set to double-side polishing apparatus,
The main surface of the two sides of glass substrate is ground on one side.2nd milled processed is different in the 1st milled processed: free
The type of abrasive grain is different with the hardness of particle size difference and resin polishing material.It such as will include colloidal silicon dioxide conduct
The lapping liquid of free abrasive grain is supplied between the grinding pad of double-side polishing apparatus and the main surface of glass substrate, to glass substrate
Main surface is ground.
In present embodiment, chemical intensification treatment is carried out, but as needed can also be without chemical intensification treatment.In addition to
Other than 1st milled processed and the 2nd milled processed, other milled processeds can also further be added, can also be ground by one
Mill handles to complete the milled processed of two main surfaces.In addition, the above-mentioned sequence respectively handled can suitably change.
(embodiment)
In order to confirm the effect of present embodiment, glass substrate has been made using the following method.
Specifically, implementing circular hole formation processing to the discoid glass blank obtained by die pressing, center is obtained
Portion has round-meshed disk-shaped glass substrate.The discoid glass is carried out using the double-sided grinding device for having a pair of of grinding price fixing
The grinding of the upper and lower major surfaces of glass plate is handled, and makes plate thickness 0.7mm.Then, shape is carried out to the end face of the disk-shaped glass plate
Working process, making chamfering width 0.15mm, chamfer angle is 45 °, obtains inner circumferential side end face and outer peripheral side end face, implements later
End surface grinding processing.Forming grinding stone is used in shape processing processing, is carried out first by not tilting the grinding processing of grinding stone
Roughing then changes grinding stone, and the helical grinding for being 3 ° by slope handles to carry out polishing.
Later, the side wall surface and fillet surface of the glass substrate for having carried out shape processing processing are implemented at various end surface grindings
Reason.The end face of glass substrate 11 is the same direction in the processing stand that end face is contacted with block 20 with the direction of rotation of block 20.It needs
It is bright, about the processing other than end surface grinding processing, to carry out according to the content of above embodiment, produce disk use
Glass substrate.
Later processing is handled as end surface grinding, specifically, successively carrying out
1st grinding (being carried out using the polyurethane abrasive pad of cerium oxide (d50:1 μm) and hard),
Chemical intensification treatment,
2nd grinding (being carried out using colloidal silicon dioxide (d50:30nm) and soft polyurethane abrasive pad),
Cleaning treatment,
Manufacture glass substrate for disc.Manufactured glass substrate for disc is outer diameter about 65mm, internal diameter about 20mm, plate thickness
The glass substrate for disc of 2.5 inches of sizes of nominal of about 0.635mm.
In end surface grinding processing, the average grain diameter d50 of magnetic-particle is fixed as 2 μm, to the average grain of grinding abrasive grain
Diameter d50 carries out various change, changes partial size ratio, finds out grinding rate the ratio between of the side wall surface relative to fillet surface.In end surface grinding
In processing, using inner circumferential side end face as grinding object.
Used magneto-rheological fluid is under room temperature (20 DEG C) with the viscosity of 1000 (mPa seconds).
Use Fe particle as magnetic-particle, uses zirconia particles as grinding abrasive grain.
Grinding rate than the central portion by having carried out the side wall surface after 3 minutes end surface grindings and fillet surface attrition process more than
Amount is found out.
Table 1 shows partial size than the result with grinding rate ratio.
[table 1]
It follows that in order to keep side wall surface roughly the same with the grinding rate of fillet surface and make grinding rate ratio 0.8 with
On, partial size is than preferably 0.6 or less.It is more by making partial size ratio 0.4 hereinafter, grinding rate ratio 0.85 or more can be made
Preferably.Result same as above-mentioned inner circumferential side end face has also been obtained in the grinding of outer peripheral side end face.
In addition, the average grain diameter d50 of magnetic-particle is fixed as 5 μm, the average grain diameter d50 of grinding abrasive grain is carried out various
Variation changes partial size ratio, finds out the index of the grinding rate of side wall surface.About the index of grinding rate, by aftermentioned partial size ratio
Grinding rate for 1.20 sample 8 is set as 1.00.The value of grinding rate is smaller, means that the index of grinding rate is smaller.
Use Fe particle as magnetic-particle, uses zirconia particles as grinding abrasive grain.
Grinding rate than the central portion by having carried out the side wall surface after 3 minutes end surface grindings and fillet surface attrition process more than
Amount is found out.
Table 2 shows partial size than the result with grinding rate ratio.
[table 2]
As shown in Table 2, if reducing partial size ratio, the grinding rate of side wall surface is reduced.In order to ensure the grinding speed of side wall surface
The index of rate is 0.80 or more, and partial size is than preferably 0.1 or more.In particular, in order to efficiently carry out end surface grinding processing, partial size
Than being more preferably 0.2 or more.
More than, the manufacturing method of glass substrate for disc of the invention is described in detail, but the present invention is unlimited
Due to above embodiment and variation, it is of course possible to carry out various improvement, change without departing from the spirit and scope of the invention
More.
Symbol description
10 devices
11 glass substrates
11a side wall surface
11b fillet surface
12,14 magnet
16 spacers
20,62 pieces
Claims (7)
1. a kind of manufacturing method of substrate for magnetic disc comprising following end surface grinding processing: utilize and include grinding abrasive grain and magnetism
The magnetic functional fluid of particle to the side wall surface with disk-shaped substrate and is set to the side wall surface and the substrate simultaneously
Main surface between the end face of fillet surface ground,
The manufacturing method is characterized in that,
Before end surface grinding processing, the partial size of partial size of the preparatory partial size for obtaining grinding abrasive grain relative to magnetic-particle
Than, with being ground using the magnetic-particle and the magnetic functional fluid of grinding abrasive grain with the partial size ratio to the end face of substrate when
The relationship of the ratio between the grinding rate of side wall surface of the grinding rate of the fillet surface of substrate relative to substrate, according to as the end face
The ratio between target grinding rate between the side wall surface and fillet surface of the substrate of the object of milled processed sets the partial size ratio
Value makes the magnetic functional fluid of the magnetic-particle and grinding abrasive grain with the value as set partial size ratio,
In end surface grinding processing,
The block of the magnetic functional fluid is formed by magnetic generating unit,
Relatively move the end face of the substrate of the object as end surface grinding processing in the state of with described piece of contact, thus right
It is ground the end face of substrate.
2. the manufacturing method of substrate for magnetic disc as described in claim 1, wherein make institute used in the end surface grinding processing
Stating the partial size ratio in magnetic functional fluid is 0.6 or less.
3. the manufacturing method of substrate for magnetic disc as claimed in claim 1 or 2, wherein make used in the end surface grinding processing
The magnetic functional fluid in the partial size ratio be 0.1 or more.
4. the manufacturing method of substrate for magnetic disc as claimed in claim 1 or 2, wherein the average grain diameter d50 of the grinding abrasive grain
In 0.1 μm~10 μm of range.
5. the manufacturing method of substrate for magnetic disc as claimed in claim 1 or 2, wherein the average grain diameter d50 of the magnetic-particle
In 0.5 μm~20 μm of range.
6. the manufacturing method of substrate for magnetic disc as claimed in claim 1 or 2, wherein the substrate and the magnetic function stream
The substrate at the contact position of body is 50m/ minutes relative to the relative velocity of the peripheral speed of the magnetic functional fluid
~500m/ minutes.
7. the manufacturing method of substrate for magnetic disc as claimed in claim 1 or 2, wherein the substrate is to glue main surface each other
Patch and it is more than lamination two panels made of substrate laminate each laminated substrate, in end surface grinding processing, while to described
It is ground the end face of each laminated substrate of substrate laminate.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014072336 | 2014-03-31 | ||
| JP2014-072336 | 2014-03-31 | ||
| PCT/JP2015/060222 WO2015152278A1 (en) | 2014-03-31 | 2015-03-31 | Method for manufacturing magnetic disk-use substrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106030710A CN106030710A (en) | 2016-10-12 |
| CN106030710B true CN106030710B (en) | 2019-01-18 |
Family
ID=54240597
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201580010429.1A Expired - Fee Related CN106030710B (en) | 2014-03-31 | 2015-03-31 | The manufacturing method of substrate for magnetic disc |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JP6353524B2 (en) |
| CN (1) | CN106030710B (en) |
| MY (1) | MY178076A (en) |
| SG (1) | SG11201606686SA (en) |
| WO (1) | WO2015152278A1 (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080085428A1 (en) * | 2004-08-16 | 2008-04-10 | Showa Denko K.K. | Silicon Substrate For Magnetic Recording Meduim, Method Of Manufacturing The Silicon Susbstrate And Magnetic Recording Medium |
| US20110159321A1 (en) * | 2009-12-29 | 2011-06-30 | Hoya Corporation | Glass substrate for magnetic disk and manufacturing method thereof |
| CN102729141A (en) * | 2011-03-31 | 2012-10-17 | Hoya株式会社 | Disc glass substrate manufacturing method |
| JP2012216278A (en) * | 2011-03-31 | 2012-11-08 | Hoya Corp | Method for manufacturing glass plate for magnetic disk and method for manufacturing magnetic disk |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005050501A (en) * | 2003-07-15 | 2005-02-24 | Hoya Corp | Method and device for manufacturing substrate for magnetic disk, and method of manufacturing magnetic disk |
| JP5821188B2 (en) * | 2010-12-27 | 2015-11-24 | 旭硝子株式会社 | Manufacturing method of glass substrate for information recording medium |
-
2015
- 2015-03-31 CN CN201580010429.1A patent/CN106030710B/en not_active Expired - Fee Related
- 2015-03-31 MY MYPI2016703183A patent/MY178076A/en unknown
- 2015-03-31 JP JP2016511952A patent/JP6353524B2/en not_active Expired - Fee Related
- 2015-03-31 WO PCT/JP2015/060222 patent/WO2015152278A1/en active Application Filing
- 2015-03-31 SG SG11201606686SA patent/SG11201606686SA/en unknown
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080085428A1 (en) * | 2004-08-16 | 2008-04-10 | Showa Denko K.K. | Silicon Substrate For Magnetic Recording Meduim, Method Of Manufacturing The Silicon Susbstrate And Magnetic Recording Medium |
| US20110159321A1 (en) * | 2009-12-29 | 2011-06-30 | Hoya Corporation | Glass substrate for magnetic disk and manufacturing method thereof |
| CN102729141A (en) * | 2011-03-31 | 2012-10-17 | Hoya株式会社 | Disc glass substrate manufacturing method |
| JP2012216278A (en) * | 2011-03-31 | 2012-11-08 | Hoya Corp | Method for manufacturing glass plate for magnetic disk and method for manufacturing magnetic disk |
Also Published As
| Publication number | Publication date |
|---|---|
| SG11201606686SA (en) | 2016-09-29 |
| MY178076A (en) | 2020-10-01 |
| JP6353524B2 (en) | 2018-07-04 |
| JPWO2015152278A1 (en) | 2017-04-13 |
| CN106030710A (en) | 2016-10-12 |
| WO2015152278A1 (en) | 2015-10-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6215770B2 (en) | Glass substrate for magnetic disk, magnetic disk, and method for manufacturing glass substrate for magnetic disk | |
| CN108133714B (en) | Glass substrate for disc | |
| JP6490842B2 (en) | Grinding tool, glass substrate manufacturing method, magnetic disk glass substrate manufacturing method, and magnetic disk manufacturing method | |
| JP6156967B2 (en) | Glass substrate manufacturing method, magnetic disk manufacturing method, and glass substrate end surface polishing apparatus | |
| JP6148345B2 (en) | Manufacturing method of non-magnetic substrate | |
| JP6001815B1 (en) | Manufacturing method of magnetic disk substrate and grinding wheel | |
| JPWO2014051127A1 (en) | Manufacturing method of glass substrate for magnetic disk | |
| CN106030710B (en) | The manufacturing method of substrate for magnetic disc | |
| JP2016126808A (en) | Method for manufacturing substrate for magnetic disk and end surface polishing device | |
| JP6170557B2 (en) | Manufacturing method of glass substrate for magnetic disk, manufacturing method of magnetic disk, grinding wheel | |
| JP2015069668A (en) | Manufacturing method of magnetic disk glass substrate and manufacturing method of magnetic disk | |
| JP6392634B2 (en) | Nonmagnetic substrate manufacturing method and polishing apparatus | |
| CN105580077B (en) | Method for manufacturing glass substrate for magnetic disk and method for manufacturing magnetic disk | |
| JP2015069675A (en) | Method for manufacturing glass substrate for magnetic disk and method for manufacturing magnetic disk | |
| WO2014104377A1 (en) | Method for manufacturing glass substrates for magnetic disks and method for manufacturing magnetic disks | |
| JP2015069687A (en) | Method of manufacturing glass substrate for magnetic disk and method of manufacturing the magnetic disk |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20190118 |