CN102950538A

CN102950538A - Polishing device for plate-shaped body and polishing system

Info

Publication number: CN102950538A
Application number: CN2012102956307A
Authority: CN
Inventors: 福田真; 中谷嘉孝; 山本一义; 木村刚; 秋山秀; 横田稔
Original assignee: Asahi Glass Co Ltd
Current assignee: AGC Inc
Priority date: 2011-08-17
Filing date: 2012-08-17
Publication date: 2013-03-06
Anticipated expiration: 2032-08-17
Also published as: CN102950538B; TWI526276B; KR20130020614A; JP5375895B2; TW201309417A; JP2013039639A

Abstract

The present invention relates to a polishing device for a plate-shaped body and a polishing system thereof, including a plate-shaped body maintaining unit for maintaining the length of one side of the plate-shaped body more than 1000mm, a polishing pad which is arranged relative to the maintaining unit and is provided with multi pulp supply holes which are formed on the relative surface relative to the plate-shaped body and can supply pulp to the polishing pad and the propping part of the plate-shaped body, and a pulp abosorption hole which is only formed on the center of the relative surface relative to the plate-shaped body and absorbes the pulp supplied to the propping part.

Description

Plate body lapping device and grinding system

Technical field

The present invention relates to plate body lapping device and grinding system.

Background technology

The employed FPD(Flat Panel such as liquid crystal display Display) glass substrate of usefulness, the glass method for making that utilization is called float glass process is configured as melten glass tabular, lapping device by disclosed continous way in patent documentation 1 grade, the small concavo-convex and ripple grinding on surface is removed, thus, this plate glass is made the thin plate that has satisfied the desired flatness of glass substrate of using as FPD.

Such as patent documentation 1 described lapping device, use with dispersant to make grinding-material disperse the slurry that forms, the surface of grinding glass substrate (below, be called the face of being polished).Slurry is supplied with to abradant surface and being polished between the face of glass substrate of grinding pad from the slurry supply hole of the central portion of being located at grinding pad.When inhomogeneous on abradant surface to the amount that is polished the slurry of supplying with between the face of the abradant surface of grinding pad and glass substrate, the flatness variation of the face that is polished of the glass substrate after being polished.Therefore, the slurry of supplying with need to evenly spread on the abradant surface.

The applicant has proposed a kind of grinding pad in Japanese Patent Application 2010-111116 number, it is in order to make the slurry of supplying with evenly spread over being polished on the face of glass substrate, and be provided with the slurry supply hole in the central authorities of abradant surface, utilize a plurality of grooves that form toward the outer side from the center abradant surface to be divided into radial.

In addition, the lapping device put down in writing of patent documentation 2 for example, its grinding pad has the high abradant surface of flatness at the face relative with substrate, on abradant surface along fore-and-aft direction roughly uniformly-spaced to be formed with a plurality of grooves, when attrition process, promote the diffusion of grinding agent, and, in the inside of grinding pad, up/down perforation and the grinding agent supply hole relative with substrate and grinding agent tap abradant surface roughly whole alternately arrange be formed with a plurality of.

Patent documentation

Patent documentation 1: the JP 2004-122351 of Japan communique

Patent documentation 2: the JP 2009-125873 of Japan communique

But, as prior art, at concentrated flow that the slurry that makes the central portion that supplies to grinding pad forms by the abradant surface at grinding pad to the outside of grinding pad and in the method for discharging, have the limit aspect the flow that increases slurry, the flow of control slurry also guarantees that near the amount of grinding the central authorities is very difficult.

For example, in the lapping device as patent documentation 1, use as mentioned above with dispersant to make grinding-material disperse the slurry that forms, the face that is polished of grinding glass substrate.At this moment grinding in the situation of the glass substrate more than the 1000mm on one side, spreading on whole of the face that is polished of glass substrate in order to make slurry, needing to increase the slurry quantity delivered.But the slurry quantitative change of supplying with from the supply hole of grinding pad reaches to supplying to more than the amount of slurry of circumference by the central portion of the groove on the abradant surface that is formed at grinding pad from glass substrate.Namely, as shown in figure 10, supply with slurry S at the slurry supply hole 330 from the central authorities that are located at grinding pad 320 on one side, on one side be attached to the glass substrate G on the film body 310 of bearing with 320 pairs of grinding pads the face that is polished when grinding, accumulating at the central portion Z of glass substrate G has slurry S.There are the following problems for its result, that is, the central portion Z of glass substrate G leaves grinding pad 320, and the central portion Z of glass substrate G is difficult to be polished, and produces to grind deficiency.

In addition, in the motion of above-mentioned patent documentation 2 records, during grinding, slurry is polished whole of pad and attracts and be discharged to outside the glass substrate, but when slurry being set in addition attracting the hole, the amount of slurry of circumference that is fed into the face that is polished of glass substrate tails off, and damage etc. easily occurs to grind.In addition, owing to attracting the capacity of the suction pump of slurry also to be limited, therefore, need to increase suction pump.So, the pipe arrangement path complicated of the supply of slurry and attraction, cost and maintenance increase.In addition, it is that larger its of glass substrate adjusted more complicated problem that object is ground in slurry is supplied with and the control of attraction becomes trouble, especially existence.

Summary of the invention

The present invention foundes in view of this problem; its purpose is to provide plate body lapping device and grinding system; especially when grinding large-sized substrate; do not reduce slurry flow; and can reduce to swell thickness (" carrying on the back thick ") and guarantee near the amount of grinding the substrate center and grind normally; and, carry out well the circulation of slurry, thereby the composition of the substrate after can suppressing to grind is attached to the face that is polished of substrate again.

For realizing described purpose, the invention provides a kind of plate body lapping device, have: the plate body holding unit, keeping length on one side is the above plate body of 1000mm; Grinding pad, be oppositely arranged with the described plate body that is kept by described plate body holding unit, described grinding pad is formed with: a plurality of slurry supply holes, form at the opposite face relative with described plate body, and supply with slurry to the abutting part of described grinding pad and described plate body; Slurry attracts the hole, and only the central portion at the opposite face relative with described plate body forms, and attracts to be fed into the described slurry of described abutting part.

Thus, even in the situation of grinding the large-sized tabular substrate more than square of 1000mm for example, attract slurry by the central portion from grinding pad only, also can not reduce slurry flow, can guarantee near the amount of grinding the central authorities, grind normally.

In addition, as an embodiment, the center that is preferably formed with the central portion of the opposite face relative with described plate body that described slurry attracts the described grinding pad in hole and is the described grinding pad of distance be described grinding pad diameter 25% with interior scope.

Like this, from the central portion attraction slurry of grinding pad, can not reduce slurry flow by only, can guarantee near the amount of grinding that central authorities are, grind normally.

In addition, as an embodiment, preferably be formed with a plurality of grooves along any direction linearity ground on the opposite face relative with described plate body of described grinding pad, the width that is formed at the groove of described central portion along the direction with described any direction quadrature forms widelyr than the width of the groove in the outside that is formed at described central portion along the direction with described any direction quadrature.

In addition, as an embodiment, preferably also possess: the unit that described grinding pad is relatively swung in the horizontal direction with respect to described plate body holding unit; With the unit that makes described grinding pad rotation and revolution, be formed with a plurality of grooves along described swaying direction linearity ground on the opposite face relative with described plate body of described grinding pad, the width that is formed at the groove of described central portion along the direction with described swaying direction quadrature forms widelyr than the width of the groove in the outside that is formed at described central portion along the direction with described swaying direction quadrature.

Thus, the slurry of grinding pad central portion can be discharged well, can guarantee near the amount of grinding that central authorities are.

In addition, as an embodiment, preferred described central portion refer to the center of the described grinding pad of distance be described grinding pad diameter 25% with interior scope.

In addition, similarly in order to realize described purpose, grinding system of the present invention has: the plate body holding unit, and keeping length on one side is the above plate body of 1000mm; Grinding pad, be oppositely arranged with the described plate body that is kept by described plate body holding unit, be formed with at described grinding pad: a plurality of slurry supply holes, form at the opposite face relative with described plate body, supply with slurry to the abutting part of described grinding pad and described plate body; Slurry attracts the hole, and only the central portion at the opposite face relative with described plate body forms, and attracts to be fed into the described slurry of described abutting part, and described grinding system has: slurry tank, accumulate contain abrasive particle slurry as grinding agent; The slurry feed unit is supplied with described slurry via described slurry supply hole to the abutting part of described grinding pad and described plate body from described slurry tank; The slurry recovery unit attracts the hole to attract to be fed into the described slurry of described abutting part via described slurry, make attract to this slurry return described slurry tank; Densimeter is located at described slurry feed unit and is detected the concentration of described slurry; Control part, testing result based on described densimeter, concentration at described slurry is lower than in the situation of predefined lower limit, control to add the additive of grinding-material and regulation to described slurry tank, and, concentration at described slurry surpasses in the situation of predefined higher limit, controls to carry out the cleaning of described densimeter.

Thus, make slurry circulation and utilize the concentration of densimeter test slurry, in the low situation of the lower limit of concentration value ratio regulation, in slurry, append cerium oxide and additive, or in the situation that concentration value surpasses the set upper limit value when carrying out the cleaning of densimeter, can make grinding rate be maintained certain and guarantee amount of grinding, thereby and increase glass ingredient again adhering to abradant surface after the slurry internal circulating load suppresses to grind.

In addition, as an embodiment, the additive of preferred described regulation is the dispersant that prevents described grinding-material aggegation.

Thus, can prevent the aggegation of cerium oxide, keep grinding rate.

In addition, as an embodiment, the cleaning of preferred described densimeter surpasses in the situation of predefined higher limit in the concentration of described slurry to be carried out, and/or carried out every 30 minutes～40 minutes.

Thus, densimeter can not stop up and detect unusual value, always can correctly carry out the detection of concentration value.

The invention effect

As described above, according to the present invention, even in the situation of grinding the large-sized tabular substrate more than square of 1000mm for example, also can not reduce slurry flow, and can guarantee near the amount of grinding the central authorities and grind normally.In addition, make slurry circulation and utilize the concentration of densimeter test slurry, in the low situation of the lower limit of concentration value ratio regulation, in slurry, append cerium oxide and additive, perhaps in the situation that when surpassing the set upper limit value and carry out the cleaning of densimeter with concentration value, grinding rate can be maintained in certain and guarantee amount of grinding, and, by increasing slurry internal circulating load, glass ingredient again the adhering to abradant surface after can suppressing to grind.

Description of drawings:

Fig. 1 is that expression is as the top view of the unitary construction of the lapping device of an embodiment of the plate body lapping device that is used for grinding system of the present invention;

Fig. 2 is film framework and the assembling stereogram that the bearing of film framework is installed;

Fig. 3 is the side view of the embodiment of expression grinding table and grinding head;

Fig. 4 is the top view of the grinding pad of lapping device shown in Figure 1;

Fig. 5 is the top view that the slurry on expression grinding pad surface attracts the formation scope in hole;

Fig. 6 A is the profile of groove of central portion of the abradant surface of grinding pad;

Fig. 6 B is the profile of groove in the outside of the abradant surface of grinding pad;

Fig. 7 is the skeleton diagram of expression slurry recycling system;

Fig. 8 is that expression is based on the coordinate diagram of the time variation of the concentration detected value of densimeter;

Fig. 9 A is the top view of amount of grinding of the diverse location of the expression face that is polished that carried out the glass substrate of slurry when attracting;

Fig. 9 B is the top view of amount of grinding of diverse location of the face that is polished of the glass substrate when representing not carry out slurry and attracting;

Figure 10 is the profile of the problem supplied with of the slurry of the existing lapping device of expression.

Label declaration

The 10:(plate body) lapping device

12: glass substrate is moved into and is used conveyer

14: film framework (plate body attaching member)

16: glass substrate attaches platform

18: the first grinding tables

20: the second grinding tables

22: the glass substrate disassembly table

24: glass substrate is taken out of and is used conveyer

26: film framework rinsing table

28: film framework drying table

30: film framework return conveyor

32: robot

33: arm

34: absorption layer

36: conveyer

38: film body

51: main body cover

52: bearing (plate body holding unit)

56: main shaft

58,60: grinding pad

62: grinding plate

64: grinding table

122: the slurry supply hole

124: slurry attracts the hole

126: groove

128: swivel coupling

130: slurry tank

132,134: pump

136: the punch metal filter

138: flowmeter

140: densimeter

142: control part

144,148: magnetic valve

146: the grinding-material accommodating container

149: the dispersant accommodating container

150: Handling device

200: control part

The specific embodiment

Below, with reference to accompanying drawing, plate body lapping device of the present invention and grinding system are at length described.

Fig. 1 is that expression is as the top view of the unitary construction of the lapping device of an embodiment of the plate body lapping device that is used for grinding system of the present invention.

Lapping device 10 shown in Figure 1 for example is that large-sized glass substrate G that vertical 1000mm * horizontal 1000mm or this size is above and thickness are that following (for example the face that is polished of the large-scale glass substrate G of thickness 0.2mm～0.7mm) is ground to the lapping device of the needed flatness of liquid crystal display glass substrate to 0.7mm.

Lapping device 10 mainly possesses: the glass substrate of moving into the glass substrate G before grinding moves into conveyer 12, glass substrate G is attached to glass substrate on the film framework (plate body attaching member) 14 attaches platform 16, the first grinding table 18, the second grinding table 20, will grind glass substrate disassembly table 22, glass substrate that the glass substrate G that finishes dismantles from film framework 14 and take out of and use conveyer 24, film framework rinsing table 26, film framework drying table 28 and film framework return conveyor 30.

Below, for the purpose of simplifying the description, attach platform 16, the first grinding table 18, the second grinding table 20, glass substrate disassembly table 22, film framework rinsing table 26 and film framework drying table 28 for glass substrate, be designated as simply

platform

16,18,20,22,26,28.

On lapping device 10, the Handling device 154 that be provided with the Handling device 150 of the 18 carrying film frameworks 14 from platform 16 to platform, the Handling device 152 of 20 carrying film frameworks 14 reaches the 22 carrying film frameworks 14 from platform 20 to platform from platform 18 to platform.These Handling devices 150,152,154 are same formation, control its action by the control part 200 of unified control lapping device 10, on Fig. 1, synchronously move back and forth at left and right directions.

Moved into the glass substrate G before the grinding of moving into conveyer 12 by glass substrate, absorption layer 34 absorption of being located on the arm 33 of robot 32 keep.And, move into conveyer 12 from glass substrate by the spinning movement of arm 33 and to move to conveyer 36, be carried to platform 16 by conveyer 36.

On platform 16, the glass substrate G before grinding is attached on the film framework 14.

Fig. 2 represents film framework 14 and the assembling stereogram of the bearing 52 of film framework 14 is installed.

As shown in Figure 2, film framework 14 is after being arranged between identical rectangular-shaped upper frame 40 and the underframe 42 by rectangular-shaped film body 38 tensionings that can attach glass substrate G, and is with not shown bolt that upper frame 40 and underframe 42 is fastening and consist of.

In addition, film framework 14 and film body 38 are not limited to rectangular-shaped, also can be round-shaped.

The method that glass substrate G before will grinding is attached on the film framework 14 describes, film framework 14 is kept by not shown lowering or hoisting gear on platform 16, glass substrate G is arranged in the below of film framework 14, then, it is mobile that film framework 14 utilizes lowering or hoisting gear to descend, and tensioning is arranged at the face that is polished that the film body with flexible and self-adsorptivity 38 on the film framework 14 shown in Figure 2 is pressed towards glass substrate G.Utilize this pressing force, the face that is polished of glass substrate G is attached on the film body 38.Afterwards, film framework 14 is kept by the Handling device 150 of Fig. 1 and is carried to platform 18, is installed at platform 18 on the bearing (plate body holding unit) 52 of grinding head (aftermentioned).In addition, said film framework 14 below refers to that tensioning is provided with the integral body of film body 38.

In addition, as shown in Figure 2, in the upper periphery section of bearing 52, hoisting frame 78 is fixed by not shown bolt.At the flange part of hoisting frame 78, through

hole

80,80 ... with the regulation uniformly-spaced opening, through

hole

80,80 ... in, be through with from the below and be based in travelling carriage 82(slide-contact frame) the travelling carriage suspender 84 of upper surface.In addition, travelling carriage suspender 84 connects and promotes springs 88, and is connected with not shown screw jack.

Then, make the screw jack action, opposing promotes the application of force of spring 88, and travelling carriage suspender 84 is stretched upward, and travelling carriage 82 is raised with respect to bearing 52 thus.Thus, the film framework 14 that freely is installed on the travelling carriage 82 of loading and unloading is raised, the tension force that film body 38 is stipulated.

In addition, be connected with main shaft 56 at bearing 52.

Fig. 3 is the side view of the embodiment of expression grinding table and grinding head.

Then, grinding head shown in Figure 3 50 is described.In addition, the grinding head 50 of platform 18 and the grinding head of platform 20 50 are same structure, therefore, mark same label and describe.

As shown in Figure 3, grinding head 50 possesses main body cover 51, in main body cover 51, in not shown revolution driving mechanism section is housed.Revolution driving mechanism section is made of planetary gears section and motor, is connected with the main shaft 56 that hangs down in vertical direction by the output shaft of electric motor driven planetary gears section.As mentioned above, be connected with bearing 52 at main shaft 56.Thus, when planetary gears section was driven, bearing 52 and film framework 14 revolved round the sun centered by the revolution center of regulation.

In addition, main body cover 51 shown in Figure 3 is connected with elevating mechanism 156 via slide block 158.Utilize elevating mechanism 156, main body cover 51 is carried out lifting with respect to slide block 158, thus, bearing 52 is with respect to the movement of advancing and retreat of the grinding pad 60 of the circle of the grinding pad 58 of the circle of platform 18 and platform 20, and the abradant surface that is attached to the glass substrate G on the film framework 14 is pressed against on the grinding

pad

58,60 by the grinding pressure with regulation.

In addition, also can pull down slide block 158 from lapping device 10, main body cover 51 directly is connected with elevating mechanism 156.

Grinding pad 58 is attached to the upper surface of grinding plate 62.Grinding plate 62 is rotatably freely supported on the grinding table 64 via bearing (not shown), the central shaft of its pivot and grinding pad 58 be set in coaxial on.And by driving not shown motor, grinding pad 58 rotates (rotation) centered by its central shaft.In addition, grinding pad 58 sides can not rotated sometimes yet, may not need motor.Also can as following the record, make grinding pad 58 side oscillations.

Grinding table 64 is slided by the pair of guide rails 69 of configured in parallel, 69 and moves freely supporting.Make grinding table 64 along the drive division (not shown) of

guide rail

69,69 reciprocating actions by possessing, grinding pad 58 swings where necessary in the horizontal direction.The swaying direction of grinding pad 58 can be and direction based on the carrying direction quadrature of the Handling device 150 of Fig. 1, also can be the direction parallel with the carrying direction.That is, so long as the direction that grinding pad 58 is swung in the horizontal direction get final product.

In addition, be connected with for many flexible pipes (not shown) from slurry to the rear side of grinding pad 58 that supply with at grinding plate 62.In order not make these soft tube windings, limit its rotation with grinding pad 58 from the mode that the reference position of stipulating begins to rotate in the angular range of regulation.The slurry that supplies to the rear side of grinding pad 58 from above-mentioned flexible pipe is fed into the abradant surface of grinding pad 58 by the slurry supply hole that connects grinding pad 58 inside.

In addition, the revolution such as the revolution rotating speed of the rotational action such as the scope of the rotational angle of grinding pad 58, velocity of rotation, time per unit action is controlled independently by the control part 200 of Fig. 1.

In addition, consist of about each one of grinding pad 60, identical with the formation of above-mentioned grinding pad 58, therefore, the description thereof will be omitted at this.

In addition, such as Fig. 3, at the slide block 158 of platform 18 straight action-oriented spare 70,70 is installed.Straight action-oriented spare 70,70 and

guide rail

72,72 chimeric.This

guide rail

72,72 is towards the maintenance platform 74 of shown in the dotted line of Fig. 1 main shaft 56 and the bearing 52 of platform 18 being keeped in repair and configure.

In addition, as shown in Figure 3, straight action-oriented spare 70,70 is installed too on the slide block 158 of platform 20, straight action-oriented spare 70,70 and guide rail 160,160 chimeric.This guide rail 160,160 is towards the maintenance platform 76 of shown in the dotted line of Fig. 1 main shaft 56 and the bearing 52 of platform 20 being keeped in repair and configure.

In addition, also can pull down slide block 158 from lapping device 10, straight action-oriented spare 70,70 directly is installed on lowering or hoisting gear 156.

In addition, be provided with air chamber not shown in Fig. 3 at bearing 52, be communicated with the air supply road 102 that dots on Fig. 3.Air supply road 102 arranges to the outside of grinding head 50 via the not shown swivel coupling extension that is installed on the grinding head 50, is connected with air pump 106 via valve 104.Thus, when relief valve 104, be supplied to the air chamber of being located at bearing 52 via air supply road 102 from the compressed air of air pump 106.The compressed-air actuated pressure that is fed into this air chamber is passed to glass substrate G via film body 38, utilizes this pressure, and the face that is polished of glass substrate G is urged on the grinding

pad

58,60 of Fig. 3 and is polished.

The grinding of glass substrate G is implemented with two stages as follows, namely, the film framework 14 that utilizes Handling device shown in Figure 3 150 will be pasted with glass substrate G is transported to platform 18 from platform 16, after on the platform 18 face that is polished of glass substrate G being ground, the film framework 14 that utilizes Handling device 152 will be pasted with glass substrate G is transported to platform 20 successively from platform 18, and the face that is polished to glass substrate G on platform 20 grinds.

Present embodiment is provided with the slurry that attracts slurry and attracts the hole near the slurry supply hole of the central portion of the abradant surface of grinding pad, attract the hole to attract slurry and make it to return from slurry, make thus the slurry circulation, the back pressure that minimizing produces at the central portion of the abradant surface of grinding pad and guarantee desirable amount of grinding, thus grind normally.

Fig. 4 be lapping device 10 shown in Figure 1 grinding pad 58(as previously mentioned, grinding pad 60 also is same formation, therefore, below, describe as grinding pad 58) top view.

Fig. 4 represents to be formed at the groove 126 that slurry supply hole 122 on the abradant surface of grinding pad 58 and slurry attract hole 124 and be used for flowing through slurry.

As shown in Figure 4, on the abradant surface of grinding pad 58, be provided with enclosing in vain the slurry supply hole 122 that represents, the slurry attraction hole 124 of using black circle to represent.The number of number, configuration and the groove 126 in slurry supply hole 122 shown in Figure 4 and slurry attraction hole 124 is an example only, and there is no particular limitation, in fact is formed with more groove 126 etc.

Like this, not shown in grinding pad 58 and glass substrate G(Fig. 4) between supply with slurry slurry supply hole 122 grinding pad 58 roughly whole be provided with many (for example, dozens ofs).

On the other hand, attract the slurry of slurry to attract hole 124 only to form at the central portion of grinding pad 58, especially attract slurry from central portion.

Fig. 5 is the top view that the slurry of the abradant surface of expression grinding pad 58 attracts the formation scope in hole.

Shown in the circle of with dashed lines among Fig. 5, form the scope in slurry attraction hole 124 at the abradant surface of grinding pad 58, be preferably the inside region F that retouches the circle of drawing from the center of grinding pad 58 with radius C.At this, radius C is below 25% of diameter H of the abradant surface of grinding pad 58.Radius C be diameter H 25% in the time, the grinding of central portion of the face that is polished that can eliminate glass substrate G is not enough, surpass diameter H 25% the time, slurry is difficult to spread over the circumference of the abradant surface of glass substrate G.

In addition, as shown in Figure 4, abradant surface at grinding pad 58 is formed with groove 126(i.e. so-called " annular knurl "), this groove 126 is used for making the flows outside of slurry from the central portion of grinding pad 58 to grinding pad 58 of central portion that supplies to the abradant surface of grinding pad 58 from the slurry supply hole, thereby it is whole to make slurry spread all over the abradant surface of grinding pad 58.

This make groove 126 that slurry flows through along with grinding head 50(Fig. 3 of the wobbling action that carries out straight line with reference to) diameter H(Fig. 4 of the abradant surface swaying direction almost parallel, grinding pad 58 in dotted line), spread all over the whole D of diameter H, and form the linearity with diameter H approximate vertical.That is, groove 126 is formed at the direction with the swaying direction quadrature of grinding head 50.

In addition, as shown in Figure 4, along diameter H, in central portion E and its outside of diameter H, the width of groove 126 is different.That is, at the central portion E of diameter H, form widelyr than the width in the outside of central portion E, along diameter H, in the outside of central portion E, form narrowlyer than the width of central portion E with respect to the whole D of diameter H.In addition, at this, the width of groove 126 refers to as representing with label W1 among Fig. 6 A and shown in label W2 among Fig. 6 B, forms the turning of raised line of groove l26 and the distance between the turning.

Why form like this width of groove 126, be for the slurry that makes the central portion E that lodges in grinding pad 58 easily by the groove 126 that is formed at central portion E two ends from groove 126 discharge to the outside of groove 126, avoid thus being detained slurry at central portion.In addition, the degree of depth of the outside of central portion E and central portion E groove 126 separately can be identical, also can be different.

Fig. 6 A is the profile along the groove of the central portion E of diameter H of the abradant surface of grinding pad 58 shown in Figure 4, and Fig. 6 B is the profile along the groove in the outside of the central portion E of diameter H of the abradant surface of grinding pad 58.At the central portion E of grinding pad 58, the side cross sectional shape of groove 126 is concavity, and its width W 1 is 3mm.In addition, in the outside along the central portion E of diameter H of the abradant surface of grinding pad 58, the side cross sectional shape of groove 126 is concavity, and its width W 2 is 1.5mm.But width W 1, W2 are not limited to above-mentioned value, are preferably 1.5～3.0mm.In addition, interval L1, the L2 of groove 126 are 3mm, but are not limited to this, are preferably 3.0～9.0mm.Degree of depth T1, the T2 of groove 126 are 2.0mm, but are not limited to this, and degree of depth Tl, T2 need only identical.

Therefore, on the abradant surface of grinding pad 58, as shown in Figure 4, be formed with groove 126 these both sides that slurry supply hole 122 and slurry attract hole 124, flow through slurry.

In the present embodiment, abutting part to grinding pad 58 and glass substrate G is supplied with slurry, and attract slurry and make slurry return slurry tank (aftermentioned), the slurry after returning is supplied with to the abutting part of grinding pad 58 and glass substrate G again, thereby makes the slurry circulation.

Fig. 7 represents the skeleton diagram of this slurry recycling system.

As shown in Figure 7, opposite face side at the abradant surface 58a of grinding pad 58 is provided with swivel coupling 128, via this swivel coupling 128, supply with slurries from the slurry supply hole 122 of the abradant surface 58a integral body that is formed at grinding pad 58, and, attract hole 124 to attract slurries from the slurry of the central portion of the abradant surface 58a that is formed at grinding pad 58.

In the situation that supply with slurry, by pump 132 slurry is taken into slurry feeding pipe 123 from slurry tank 130, via swivel coupling 128 from slurry supply hole 122 to grinding pad 58 abradant surface 58a and glass substrate G(not shown among Fig. 7) abutting part supply with slurry.

In addition, in the situation that attract slurry, by pump 134, attract hole 124 to attract slurries from the slurry of the central portion of the abradant surface 58a that only is formed at grinding pad 58.The slurry that is attracted is taken into slurry reclaim line 125 via swivel coupling 128, returns slurry tank 130 via punch metal filter 136.Utilize punch metal filter 136 to remove the cullet of glass substrate G contained in the slurry that is attracted.The slurry that returns slurry tank 130 is attracted by pump 132 again, supplies to the abradant surface 58a of grinding pad 58.So carry out the circulation of slurry.

In addition, the slurry feeding pipe 123 between swivel coupling 128 and pump 132 is provided with flowmeter 138, monitors all the time the flow of the slurry of supplying with.

In addition, be provided with densimeter 140 at the pipeline 123a from slurry feeding pipe 123 branches, for example make about 10 liters of per minutes flux and flow direction branch pipeline 123a and monitor the concentration of slurry.The slurry that has passed through densimeter 140 returns slurry tank 130 again.In addition, slurry concentration refers to grinding-material shared mass ratio (quality %) in slurry.

The testing result of flowmeter 138 and densimeter 140 is transfused to control part 142.

Control part 142 is according to the testing result control pump 132,134 of flowmeter 138, thus the quantity delivered of the slurry in the control grinding.

In addition, control part 142 is according to the testing result of densimeter 140, in the situation that the concentration of slurry descends, open magnetic valve 144,130 inject grinding-material (abrasive particle) from grinding-material accommodating container 146 to slurry tank, and, open magnetic valve 148,130 inject dispersant from dispersant accommodating container 149 to slurry tank.

This is because grinding-material has the tendency of aggegation, after long-time continuous is ground, and grinding-material coagulation sedimentation and make the concentration step-down of slurry, thus, grinding rate runs down, therefore, as to the additive of slurry and add dispersant, to prevent the aggegation of grinding-material, keep grinding rate.

As grinding-material, for example can enumerate cerium oxide, zirconia, iron oxide, silica, these grinding-materials can use separately, also may be used more than two kinds.

As dispersant, for example can consider acrylic acid/maleic acid Na salt (POLITYA-550, Lion Co., Ltd. system), in addition, also can add methyl alcohol, citric acid Na etc.

In addition, in order to prevent the aggegation of grinding-material, also can apply to slurry the small voltage of 1～2.5V.

By the interpolation of these dispersants and applying of small voltage, can prevent the aggegation of grinding-material, prevent the reduction of grinding rate, and then can improve grinding rate.

Use Fig. 8 that the concentration management of the slurry that carries out according to the testing result of densimeter 140 is described.

Fig. 8 is that expression is based on the coordinate diagram of the time variation of the concentration detected value of densimeter 140.The longitudinal axis represents slurry concentration, and transverse axis represents the time.The higher limit of the longitudinal axis and lower limit are higher limit and the lower limit of the scope of desired slurry concentration.

In grinding initial stage, the slurry concentration of slurry changes in desired scope, but when having passed through certain hour, slurry concentration reduces.So, the time point t of the lower limit of predefined slurry concentration in being lower than control part 142 _L, as mentioned above, control part 142 is opened

magnetic valve

144 and 148, adds grinding-material and the dispersant of ormal weight in the slurry in the slurry tank 130.

In addition, when densimeter 140 inner slurries stopped up, slurry concentration rose.At this moment, the time point t of the higher limit of predefined slurry concentration in surpassing control part 142 _u, it is blocked that control part 142 is judged as densimeter 140, carries out the flushing (cleaning) of densimeter 140.

On densimeter 140, except pipeline 123a, be connected with the pipeline (not shown) of flushing usefulness, but in common operation, the open and close valve of the pipeline of flushing usefulness is closed, the open and close valve of pipeline 123a is opened.When washing, in order to switch to the connection of densimeter 140 pipeline of flushing usefulness from pipeline 123a, open the open and close valve of the pipeline of flushing usefulness, the open and close valve of the 123a that blinds off a line.Afterwards, the entrance from the water of Pipeline transport of flushing usefulness and compressed-air actuated mixture from densimeter 140 is entered, remove the slurry of the inside that is blocked in densimeter 140 with said mixture.The slurry of removing is discharged from the outlet of densimeter 140.After flushing finishes, to switch to pipeline 123a in order connecting from the pipeline of flushing usefulness, the open and close valve of each pipeline to be set back.

Flushing can be carried out when densimeter 140 detected concentration values have surpassed higher limit like this, but also can carry out termly according to the per 30 minutes～mode of carrying out 1 time in 40 minutes.Thus, can not occur that densimeter stops up and the situation that is detected unusual value always can correctly be carried out the detection of concentration value.

Fig. 9 A, Fig. 9 B represent the present embodiment produce an effect.Fig. 9 A, Fig. 9 B are the figure of amount of grinding of diverse location of the face that is polished of expression glass substrate G, and the amount of grinding of the circumference of the face that is polished of glass substrate G is set as 100 carries out standardization.Fig. 9 A has represented to carry out the situation that slurry attracts, and Fig. 9 B represents not carry out the situation that slurry attracts.

Shown in Fig. 9 B, attract in the situation that do not carry out slurry, the amount of grinding of the central portion of the face that is polished of glass substrate G is 80, reduces significantly than the amount of grinding of the circumference that is polished face.Relative therewith, shown in Fig. 9 A, can find out that in the situation that carried out slurry and attract, the amount of grinding of the central portion of glass substrate G is 90, make moderate progress with respect to not carrying out the situation that slurry attracts.

As described above, in the present embodiment, when grinding large-sized glass substrate more than square of 1000mm at least, thereby the slurry can attracting forcibly from the central portion of grinding pad to grind reduces the slurry that is trapped in central portion, the back pressure that suppresses slurry is guaranteed the amount of grinding of central portion.

In addition, attract slurry from the hole that is formed in the grinding pad face, make attract to slurry again be supplied to the abradant surface of grinding pad and circulate, increased the internal circulating load of slurry.In addition, the slurry in grinding by such attraction increases the internal circulating load of slurry, can reduce glass ingredient after the grinding and be trapped in situation in the slurry.In addition, the glass ingredient after can suppressing thus to grind is attached to abradant surface again.

In addition, owing to be to increase the internal circulating load of slurry by attraction, thereby the temperature that can suppress slurry rises, and suppresses dirt adhering to glass substrate.And, rise by the temperature that suppresses slurry, can suppress the softening selection abrasiveness that causes deteriorated of grinding pad.

The above at length is illustrated plate body lapping device of the present invention and grinding system, but the present invention is not limited to top example, in the scope that does not break away from aim of the present invention, can certainly carry out various improvement and distortion.

The application is based on the Japanese patent application 2011-178443 of application on August 17th, 2011, and its content is cited as reference at this.

Claims

1. plate body lapping device has:

The plate body holding unit, keeping length on one side is the above plate body of 1000mm;

Grinding pad is oppositely arranged with the described plate body that is kept by described plate body holding unit,

Described grinding pad is formed with:

A plurality of slurry supply holes form at the opposite face relative with described plate body, supply with slurry to the abutting part of described grinding pad and described plate body;

Slurry attracts the hole, and only the central portion at the opposite face relative with described plate body forms, and attracts to be fed into the described slurry of described abutting part.

2. plate body lapping device as claimed in claim 1, wherein,

The center that is formed with the central portion of the opposite face relative with described plate body that described slurry attracts the described grinding pad in hole and is the described grinding pad of distance be described grinding pad diameter 25% with interior scope.

3. plate body lapping device as claimed in claim 1 or 2, wherein,

Be formed with a plurality of grooves along any direction linearity ground on the opposite face relative with described plate body of described grinding pad, the width that is formed at the groove of described central portion along the direction with described any direction quadrature forms widelyr than the width of the groove in the outside that is formed at described central portion along the direction with described any direction quadrature.

4. such as each described plate body lapping device in the claim 1～3, wherein, also possess:

The unit that described grinding pad is relatively swung in the horizontal direction with respect to described plate body holding unit; With the unit that makes described grinding pad rotation and revolution,

Be formed with a plurality of grooves along described swaying direction linearity ground on the opposite face relative with described plate body of described grinding pad, the width that is formed at the groove of described central portion along the direction with described swaying direction quadrature forms widelyr than the width of the groove in the outside that is formed at described central portion along the direction with described swaying direction quadrature.

5. such as claim 3 or 4 described plate body lapping devices, wherein,

Described central portion refer to the center of the described grinding pad of distance be described grinding pad diameter 25% with interior scope.

6. grinding system has:

Be formed with at described grinding pad:

Slurry attracts the hole, and only the central portion at the opposite face relative with described plate body forms, and attracts to be fed into the described slurry of described abutting part,

Described grinding system has:

Slurry tank, accumulate contain abrasive particle slurry as grinding agent;

The slurry feed unit is supplied with described slurry via described slurry supply hole to the abutting part of described grinding pad and described plate body from described slurry tank;

The slurry recovery unit attracts the hole to attract to be fed into the described slurry of described abutting part via described slurry, make attract to this slurry return described slurry tank;

Densimeter is located at described slurry feed unit and is detected the concentration of described slurry;

Control part, testing result based on described densimeter, concentration at described slurry is lower than in the situation of predefined lower limit, control to add the additive of grinding-material and regulation to described slurry tank, and, concentration at described slurry surpasses in the situation of predefined higher limit, controls to carry out the cleaning of described densimeter.

7. grinding system as claimed in claim 6, wherein,

The additive of described regulation is the dispersant that prevents described grinding-material aggegation.

8. such as claim 6 or 7 described grinding systems, wherein,

9. such as each described grinding system in the claim 6～8, wherein,

The cleaning of described densimeter surpasses in the situation of predefined higher limit in the concentration of described slurry to be carried out, and/or carried out every 30 minutes～40 minutes.