JP2007007844A - Soft resin grounding stone, cylindrical grounding roll formed therefrom, and manufacturing method of grinding roll - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a soft resin grinding tone capable of grinding the surface of a soft material into a ground surface equipped with excellent flatness and specular property without generating scratches. <P>SOLUTION: The soft resin grinding tone is composed of 15-42 vol.% abrasive grains 2, 3-12 vol.% inorganic filler 3, 5-15 vol.% independent pores 4 having diameters 50-500 μm, and a resin binder as remainder, wherein the surface hardness of the resin binder 1 is 20 or more in the Shore-D value, favorably 40-90. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a soft resin grindstone, a cylindrical grinding roll using the same, and a method for manufacturing the same, and more particularly, when used for surface grinding of a soft material to be ground, a grinding operation that follows the surface irregularities of the material to be ground. A soft resin grindstone capable of finishing the ground surface into a surface excellent in flatness and specularity without causing scratches, and a cylindrical grinding roll manufactured using the same It relates to the manufacturing method.

  In the case of a circuit board in which conductor circuits of a predetermined pattern are wired on the upper and lower surfaces of the insulating base material, through-holes having a predetermined diameter are drilled in the thickness direction of the insulating substrate, and conductor circuits are formed in the upper and lower openings. A portion of the land is formed of a copper plating layer, and a copper plating layer connected to the land is formed on the wall surface of the through hole, whereby conduction between the conductor circuits on the upper surface and the lower surface is achieved. Further, depending on the construction method, in order to semipermanently protect the copper plating applied to the wall surface of the through hole, the through hole may be filled with resin ink for filling.

  When various element parts are surface-mounted on such a circuit board, the entire surface of the circuit board is ground prior to that. This is for grinding and removing the copper oxide film generated on the surface of the conductor circuit, and also for the burrs (called hole burrs) at the land edge portions that occur when drilling through holes. This is because the mounting surface is flattened by removing irregular surface irregularities on the mounting surface such as the surface bulging of the resin ink for hole filling.

Conventionally, for example, a polishing buff in which abrasive grains are kneaded into a non-woven fabric has been frequently used for this grinding process.
However, when a polishing buff is used, it is difficult to uniformly grind and remove the irregular surface irregularities described above, and not only the ink residue around the land and the land edge portion are liable to occur, but also polishing. There is a phenomenon in which fine cut pieces of the buff nonwoven fabric remain in the through-hole, that is, a so-called “buff residue”.

On the other hand, recently, various electronic devices have been rapidly reduced in size, weight, and functionality, and along with that, conductor circuits have been made thinner for circuit boards incorporated in these electronic devices. There is a strong demand for high-density mounting of parts.
In order to meet this demand, multilayer circuit boards and through-hole diameters have been reduced, but the build-up method is mainly used for the production of multilayer circuit boards.

By the way, in the build-up method, the upper layer substrate is sequentially assembled on the lower layer substrate on which a conductor circuit having a predetermined pattern is already formed on the surface.
At that time, after grinding the surface irregularities of the conductor circuit formed on the surface of the lower layer substrate to level the entire surface, the next upper layer substrate is assembled here.
This is because if the surface of the lower layer substrate is not flattened, the surface of the upper layer substrate formed thereon is swelled or a short circuit or disconnection is likely to occur in the conductor circuit formed on the surface of the upper layer substrate.

For such flattening grinding, a cylindrical grindstone in which a resin grindstone piece is fixed to the outer peripheral surface has recently begun to be used.
For example, a cylindrical grindstone having the following structure has been proposed (see Patent Document 1).
As shown in FIG. 4, this cylindrical grindstone has, for example, a so-called light and high-rigidity phenol tube 5 impregnated with a phenol resin in a paper tube and solidified as a core tube. An elastic body 6 made of a resin and having a light and annular shape is disposed, and further, for example, a soft rubber, a metal wire 8 spirally wound around the outer periphery thereof, and a soft rubber bonded from the outside And a rubber sheet 9 having a plurality of grindstone pieces 10 bonded to one side is bonded to the outside of the support 7.

In this cylindrical grindstone, a resin grindstone in which SiC abrasive grains are kneaded with PVA resin is used, and its creep Young's modulus is preferably as low as 85 to 350 kg / mm ² .
In this cylindrical grindstone, since the support 7 and the rubber sheet 9 mainly composed of a rubber sheet directly transmit the elasticity of the elastic body 6 to the grindstone piece, the grindstone pieces 10 independently follow the uneven curved surface of the material to be ground. Therefore, it is said that grinding work with excellent adaptability can be performed.

Further, the following cylindrical resin grindstone has been proposed (see Patent Document 2).
Also in the case of this cylindrical resin grindstone, for example, a paper-phenolic resin laminated tube is used as the core tube 5, and on the outer periphery thereof, a sponge-like porous elastic layer 7a made of, for example, polyethylene foam and a dense material made of, for example, fiber-reinforced rubber, are used. An elastic body layer 7c composed of an elastic body layer 7b is disposed with the porous elastic body layer 7a inside, and a grindstone is fixed to one side of the rubber sheet outside the dense elastic body layer 7b. The rubber sheet is bonded.

The resin grindstone used in this cylindrical resin grindstone is obtained by bonding abrasive grains to a thermosetting and extremely hard resin such as phenol resin. In that case, the thermosetting resin has a three-dimensional network structure having continuous air holes smaller in diameter than the abrasive grains.
Since the thermosetting resin having such a three-dimensional network structure forms a matrix, the apparent elastic modulus of the resin grindstone as the grindstone is lower than the original elastic modulus of the resin. Therefore, the material to be ground having a soft surface can be suitably ground, and the abrasive grains fall off with a relatively weak force, so that the surface of the material to be ground is not easily scratched and has a sharpness over a long period of time. Demonstrate the effect of being secured.
JP 2001-315064 A JP 2004-337986 A

In general, when manufacturing a multilayer circuit board by the built-up method, the insulating substrate that is frequently used in each circuit board is a composite material of glass fiber cloth and epoxy resin, so the surface is soft, and the glass fiber cloth Under the influence of the mesh pattern, it has a wavy surface. And the conductor circuit of a predetermined pattern is formed in the form along this waviness surface there.
On the other hand, a resin grindstone disposed on the surface of a cylindrical grindstone generally has a relatively high hardness and generally has a poor deformability depending on the type of resin used. Therefore, when grinding the soft surface of the circuit board described above, the resin grindstone cannot follow the waviness and irregular irregularities of the substrate surface, and as a result, the convex part of the waviness surface is ground, but the waviness There arises a problem that the concave portions of the surface remain unground.

  The prior arts described in Patent Document 1 and Patent Document 2 are both cylindrical grindstones that have been proposed as one of the problems to be solved as described above. For example, in the case of the resin grindstone of Patent Document 2, Again, since the matrix is formed of a hard resin, there is a problem that the swell surface does not always follow the soft surface of the insulating substrate which is a composite material of glass fiber cloth and epoxy resin.

  Further, in the case of the resin grindstone of Patent Document 2, since the matrix has a three-dimensional network structure having continuous air holes, the apparent elastic modulus of the matrix itself is certainly lowered, and the grinding of a soft material to be ground is performed. However, on the other hand, there is a problem that the wear ratio of the grindstone during grinding is increased. This is probably because the matrix has a complex three-dimensional network structure with continuous air holes, so that the holding power of the abrasive grains by the matrix is small and the strength of the grindstone as a whole is reduced.

In addition, the cylindrical grindstones disclosed in these patent documents all have an elastic layer interposed between the core tube mounted on the rotating shaft and the grindstone piece that is located on the outermost layer and performs the grinding operation. By doing so, the grindstone pieces can correspond to the surface irregularities of the material to be ground so that the surface can be flatly ground.
Therefore, when assembling this cylindrical grindstone, in addition to the core tube and the grindstone piece, various materials intervening in the middle are necessary, and these intermediate materials are fixed to each other, for example, without floating together. Must be done.

Moreover, in order to prevent deformation due to centrifugal force accompanying high-speed rotation during grinding, it is necessary to fasten and fix the elastic layer with, for example, a metal wire (in the case of Patent Document 1).
Further, if the cylindrical grindstone continues to be used, for example, if the grindstone piece is worn, it is practically impossible to replace only the worn grindstone piece with a new grindstone piece while leaving the core tube and the intermediate material intact. This is because these grindstone pieces are bonded to a rubber sheet or the like in a predetermined arrangement.

Therefore, when the grinding wheel piece is worn out, even if a core tube or the like can be used, it is discarded that the cylindrical grinding wheel has also been used up.
The present invention has been made in view of the above-described problems when grinding a material to be ground having a soft surface. For example, the number of occurrences of “buffing” is zeroed when grinding a surface of a circuit board with a through hole. Of course, a new soft resin grindstone that can realize the formation of a flat ground surface without the occurrence of scratches and can be manufactured very easily compared to the conventional one. It aims at providing a cylindrical grinding roll and its manufacturing method.

In order to achieve the above object, in the present invention,
Abrasive grain 5-25% by volume, inorganic filler 3-12% by volume, pores 50-500 μm independent pores 5-15% by volume, the balance is made of resin binder, and the surface hardness of the resin binder is Shore D value A soft resin grindstone characterized by being 20 or more is provided.
The present invention also provides a cylindrical grinding roll comprising a grinding action portion comprising a cylindrical metal tube and the soft resin grindstone fixed to the outer peripheral surface of the cylindrical metal tube. Is done.

In that case, it is preferable that the cylindrical metal tube is made of Al or an Al alloy.
In the present invention, a cylindrical metal tube is coaxially disposed in a bottomed cylindrical mold material, and a gap formed by an inner peripheral surface of the cylindrical mold material and an outer peripheral surface of the cylindrical metal tube is formed. After injecting a uniform mixture of a liquid resin, an inorganic filler, abrasive grains, a curing agent of the liquid resin, and an independent pore forming source such as a foaming agent and various balloons, the mixture is heated to cure, and then the cylinder. There is provided a method for producing a cylindrical grinding roll characterized in that a mold part is released to form a grinding action part in which a cured product of the mixture is fixed to the outer peripheral part of the metal tube.

This soft resin grindstone is soft and flexible as the matrix resin binder itself, so it is easy to adjust to the surface of the material to be ground during grinding, and the grinding operation follows the surface irregularities. Can be processed into a ground surface with excellent flatness.
Since the fiber component is not included unlike the polishing buff, for example, even if surface grinding of a circuit board with a through hole is performed, no “buffing” is caused.

Further, although the resin bonded body is soft and flexible, the soft resin grindstone is a composite made of the resin bonded body, an inorganic filler, and abrasive grains, and has a predetermined proportion of closed cells. Therefore, the mechanical strength is high and the wear ratio during grinding is also low.
In addition, since this soft resin grindstone itself is soft and flexible, the grindstone is directly fixed to the outer peripheral surface of the metal tube to be a grinding action portion as will be described later. Even if the processing is performed, the elasticity of the grindstone itself is effectively exhibited, and a flat grinding of the material to be ground can be realized.

Therefore, the cylindrical grinding roll of the present invention can be assembled without interposing an elastic body between the grindstone and the core tube as in the prior art. Can also be manufactured at low cost.
In the case of this cylindrical grinding roll, since a lightweight cylindrical metal tube such as an Al tube is used for forming the grinding action portion, even if the resin grinding stone is worn out by long-term use, For example, a metal tube can be reused by reclaiming the metal tube by lathe processing and re-bonding the grindstone to the outer periphery of the metal tube, for example.

An example of the soft resin grindstone of the present invention is shown in FIG. 1 as a partial cross-sectional view.
In this soft resin grindstone, resin binder 1 is used as a matrix, and abrasive grains 2 and inorganic filler 3 are uniformly dispersed therein. The abrasive grains 2 are held by the resin binder 1. In addition, independent pores 4 are formed in the resin binder and are uniformly dispersed.
In this soft resin grindstone, as the resin material of the resin binder 1 that holds the abrasive grains 2, the surface hardness in a state where 5 to 15 volume% of independent pores 4 to be described later after curing is formed is JIS K 6253. A resin having a Shore D value of 20 or more, preferably 40 to 90, when measured by a specified method is used.

When the Shore D value of the resin binder in the state including the independent pores is the above-described value, the resin binder has an appropriate flexibility and a large amount of elastic displacement. When the uneven surface is ground, the grindstone can be deformed following the surface unevenness of the material to be ground, and a ground surface having excellent flatness can be processed without causing scratches.
However, if the shore D value of the resin binder becomes too high, the soft resin grindstone becomes inflexible and it becomes difficult to exert the above-described effects. Therefore, the upper limit of the shore D value of the resin binder should be 90. Is preferred.

As will be described later, the Shore D value varies depending on the type of resin material to be used, the degree of curing thereof, the blending ratio of other components described later, and the pore diameter and volume ratio of the independent pores.
The resin material of the resin binder is not particularly limited as long as it satisfies the above-described conditions, but is generally preferably a thermosetting resin. Actually, the deterioration due to the processing heat generated during grinding is less because the thermosetting resin is shorter than the thermoplastic resin, and the service life is extended.

As such a thermosetting resin, for example, an epoxy resin, a phenol resin, a urea melamine resin, a polyester resin, a polyurethane resin, or the like can be used. In particular, an epoxy resin is suitable, and among them, a soft epoxy resin is suitable.
The abrasive grains, the invention is not particularly limited, can be used, for example _{Al 2 O 3, SiO 2,} CeO, ZrO 2, MnO 2, Cr 2 O 3, cBN, SiC, diamond, sapphire and the like. These may be used singly or in combination of two or more.

If the particle size of the abrasive grains is too large, the frequency of occurrence of scratches on the material to be ground increases during grinding, so it is preferable to regulate the particle size to 500 μm at the maximum. In particular, when trying to obtain a ground surface that does not generate scratches, it is preferable to use abrasive grains having a particle size of 100 μm or less.
In this invention, the ratio of the abrasive grain in a soft resin grindstone is set to 5-25 volume%. If this ratio is less than 5% by volume, the grinding ability as a grindstone is deteriorated and cannot be used in actual use. On the other hand, if it exceeds 25% by volume, the grinding ability increases, but on the other hand, the frequency of occurrence of scratches on the ground surface increases. A preferred ratio is 8 to 15% by volume.

The inorganic filler is blended to increase the mechanical strength of the grindstone manufactured in combination with the resin binder and to adjust the frictional force between the soft resin grindstone and the material to be ground. Moreover, it mix | blends in order to prevent that both with a specific gravity difference isolate | separate in the slurry-like mixture of liquid resin and an abrasive grain prepared at the time of manufacture of the grindstone mentioned later.
As the inorganic filler having such a function, for example, one kind or two or more kinds such as alumina whisker, silica whisker, carbon whisker, magnesium whisker, and aluminum borate whisker can be used.

When these whiskers are used, it is preferable to use these commercially available whiskers by pulverizing them with a pulverizer.
The ratio of the inorganic filler is set to 3 to 12% by volume. When this ratio is less than 3% by volume, the above-described effects are not sufficiently exhibited. In particular, since the slurry-like mixture progresses in a state where the abrasive grains and the liquid resin are separated at the time of production, the frequency of occurrence of scratches is disadvantageously increased during grinding using the obtained soft resin grindstone.

On the other hand, when the amount is more than 12% by volume, uniform dispersion of the abrasive grains in the resin binder and improvement of the mechanical strength thereof are realized, but on the other hand, the viscosity of the slurry-like mixture is increased and the moldability is deteriorated. Since the flexibility of the resin binder deteriorates, it becomes difficult to process the ground surface flatly.
A desirable ratio of the inorganic filler is 4.5 to 9.5% by volume.

In the case of this soft resin grindstone, independent pores are dispersed in the resin binder instead of continuous pores.
The independent pores affect the flexibility of the resin binder, and influence the frictional resistance between the soft resin grindstone and the material to be ground during grinding, and at the same time contribute to prevention of chipping.
For example, if the pore size of the independent pores is too large or the volume ratio thereof is too large, the frictional resistance between the grinding wheel and the material to be ground will be small, and the chipping prevention effect will be high, but the grinding stone will be soft. Too much and grinding performance will deteriorate significantly.

On the other hand, if the pore diameter is too small or the volume ratio is too small, the frictional resistance of the resin binder increases and the grinding amount increases, but it becomes difficult to remove the chips for a short time. Clogging occurs during grinding.
Therefore, in the soft resin grindstone of the present invention, the pore diameter of the independent pores is set in the range of 50 to 500 μm, and the volume ratio (porosity) in the resin grindstone is set to 5 to 15%. .

Such independent pores can be formed by adding an independent pore forming source such as a microballoon or a foaming agent to the slurry mixture during the production of a resin grindstone to be described later.
As the microballoons, for example, inorganic balloons such as glass balloons, silica balloons, alumina balloons, and shirasu balloons, and organic balloons such as phenol balloons can be used. By mixing a predetermined amount of a balloon having a desired diameter with the slurry mixture, closed cells having the above-described pore diameter can be formed in the resin binder at the volume ratio described above.

  Further, as the foaming agent, a part or all of which is thermally decomposed and gasified at the environmental temperature in the curing process of the liquid resin is used. For example, azodicarbonamide can be used. And the independent pore of an above-mentioned pore diameter can be formed in a resin binder by the above-mentioned volume ratio by selecting the usage-amount, the temperature at the time of hardening, the viscosity of a slurry-like mixture, etc. suitably.

In the soft resin grindstone of the present invention, the remainder is the above-described resin binder. The occupation ratio of the resin binder is approximately 50 to 90% by volume.
This resin grindstone is manufactured as follows.
First, a liquid resin and an inorganic filler are uniformly mixed, for example, with a stirring mixer at room temperature. In addition, when forming independent pores with a balloon, a predetermined amount of a balloon having a predetermined diameter is simultaneously added and mixed at this point.

Next, abrasive grains and a liquid resin curing agent are added and the whole is mixed to prepare a viscous slurry mixture.
This slurry-like mixture is cast into a mold having a predetermined shape and left at room temperature or heated to a suitable temperature to cure the whole. In this process, the separation of the abrasive grains and the liquid resin (precipitation of the abrasive grains) does not occur due to the action of the inorganic filler, and the curing of the mixture proceeds while the balloon is taken into the polymerized resin network. .

And after completion | finish of hardening reaction, the target resin grindstone is obtained by releasing a hardened | cured material from a mold material.
In the case where the independent pores are formed with a foaming agent, the liquid resin curing reaction in the slurry mixture described above proceeds and the mixture exhibits fluidity to the extent that mixing and stirring are possible. Add a certain amount of blowing agent to continue the mixing operation and cast into the mold.

If the amount of the foaming agent added is too small, the amount of independent pores generated will be small and the flexibility of the resin binder cannot be increased. Conversely, if the amount added is too large, the amount of independent pores generated will increase. Or the wear ratio of the resin grindstone obtained by frequent occurrence of continuous pores increases.
Next, the cylindrical grinding roll of the present invention will be described. The cylindrical grinding roll of the present invention has a structure in which the grinding action part A as shown in FIG.

The grinding part A directly covers the entire outer peripheral surface 11a of the cylindrical metal tube 11, and the soft resin grindstone 12 of the present invention already described is fixed thereto.
The metal tube 11 is preferably a light Al tube or an Al alloy tube, and the surface of the soft resin grindstone 12 is cut with an appropriate width and depth so that a flat set of grindstone pieces that do not contact each other. It is preferable to keep the body.

This grinding action part can be manufactured as follows.
In the first method, at the time of manufacturing the above-described soft resin grindstone, for example, a slurry-like mixture is cast into a box-shaped mold material, and then the top is covered with, for example, NR-17 (a rubber sheet manufactured by Tokyo Soundproof Co., Ltd.). In this state, the slurry-like mixture is cured and then released to produce a grindstone sheet in which the soft resin grindstone and the rubber sheet are integrated, and the grindstone sheet is wound around the outer peripheral surface 11a of the metal tube 12, In this method, the rubber sheet and the metal tube are bonded and fixed with an adhesive such as TX-2 (R) or TX-2 (H) (two-component hard epoxy resin manufactured by Terada Co., Ltd.).

At this time, if a cutting die is arranged on the mold material, a cut is formed on the grinding stone side of the shaped grinding stone sheet.
In addition, when the soft resin grindstone is manufactured, the resin grindstone is manufactured in a state where the slurry-like mixture poured into the mold material is covered with, for example, a male velcro tape, while a female mold is formed on the outer peripheral surface of the metal tube. A velcro tape may be wound to bond them together, a resin grindstone may be wound thereon, and a female velcro tape of a metal tube and a male velcro tape of a resin grindstone may be engaged to fix the resin grindstone.

  In the second method, as shown in FIG. 3, for example, a bottomed cylindrical mold 13 is prepared, and the metal tube 12 is coaxially inserted into the mold 13 and arranged there. Next, a slurry-like mixture is injected into a gap formed by the inner peripheral surface of the mold 13 and the outer peripheral surface 12a of the metal tube 12, and the mixture is cured by heating to a predetermined temperature, for example. Then, the mold material 13 is released. As a result, a grinding action part composed of the metal tube 12 and a resin grindstone integrated with the outer peripheral surface 12a is obtained. Finally, a cutting process is performed on the surface of the resin grindstone.

  In addition, it becomes easy to release the mold by applying a release material to the inner peripheral surface of the mold material 13 in advance, and if the outer peripheral surface 12a of the metal tube 12 is, for example, a roughened surface, the adhesion between the metal tube and the soft resin grindstone is achieved. This is preferable because the force is improved.

Examples 1 and 2 and Comparative Example Manufacture of whetstone Two-component soft epoxy resin (Nippon Pernox Co., Ltd. main agent M-150, bisphenol A type epoxy resin and polyglycol type epoxy resin mixture 90g (solid content conversion), aluminum borate whisker (Shikoku Chemicals) 7 g, fiber length 10-20 [mu] m, fiber diameter 0.1-0.5 [mu] m, glass balloon (3M, particle size 30-70 [mu] m) and alumina balloon (Pacific Random, particle size 100-500 [mu] m) 20 g of balloon mixed with a mass ratio of 9: 1 was mixed and stirred.

Next, 45 g of SiC ₂ abrasive grains (particle size # 220) was added and stirred and mixed, and a curing agent (HY-306, modified amine curing agent manufactured by Nippon Pernox Co., Ltd.) was added to the epoxy resin. The mixture was added to the main agent at a mass ratio of 100: 70 and further mixed.
Next, the obtained slurry-like mixture was poured into a mold material, left at room temperature (25 ° C.) for about 24 hours to cure the epoxy resin, and then released.
The dimension and shape of the obtained cured product were 395 mm in length, 59 mm in width, and 8 mm in thickness. This is Example 1.

As a soft epoxy resin, the main agent E-5-2 (R) manufactured by Terada Co., Ltd. (a compound of 60 to 90% bisphenol F diglycidyl ether and 5 to 30% aliphatic monoglycidyl ether) is used as a curing agent. Using E-5-2 (H) manufactured by Terada Co., Ltd. (modified polyamide 60-90%, benzyl alcohol 5-30% compound), a mixture of the glass balloon and alumina balloon having a particle size of 50-500 μm described above was used. A slurry-like mixture was prepared by the same operation as in Example 1, cast into a mold material, allowed to stand at room temperature (25 ° C.) for about 24 hours, and then cured to release the epoxy resin.
The dimension and shape of the obtained cured product were 395 mm in length, 59 mm in width, and 8 mm in thickness. This is Example 2.

2. Specifications The surface hardness of the resin binder in each cured product is affected by the temperature and humidity of the environment, so after curing the resin, leave it in an air-conditioned room at a temperature of 25 ° C., and then bond the resin in each cured product. The surface hardness of the material was measured. The hardness was measured with a rubber / plastic hardness meter (analog hardness manufactured by Ueshima Seisakusho) to determine the Shore D value. The results are shown in Table 1.

  In addition, a specimen was cut out from the cured product, and the cross section thereof was observed with an SEM to measure the size and shape of SiC abrasive grains, aluminum borate whiskers, and independent pores, and the volume ratio was calculated from the measured values. The results are shown in Table 1.

3. Performance test Each cured product is cut 14 mm long and 10 mm wide, 1 mm wide and 7 mm deep, and 13 mm long, 10 mm wide and 7 mm high grinding stone pieces are arranged at 1 mm intervals. A whetstone sheet was produced.

Then, a cylindrical Al pipe having an outer diameter of 130 mm, an inner diameter of 120 mm, a wall thickness of 5 mm, and a length of 610 mm is prepared. An epoxy adhesive is applied to the outer peripheral surface of the Al pipe, and the grinding stone sheet is wound and bonded. Then, the cylindrical grinding part was assembled, the core tube was arranged at the center, and the urethane foam resin was filled in the gap between the core tube and the grinding part to assemble the cylindrical grinding roll.
For comparison, the following grinding rolls were manufactured.

An abrasive grain SiC ₂ grains (particle size # 800), porosity of 47.7% made binder from vitreous bond material, longitudinal 14 mm, lateral 10 mm, commercially available vitrified abrasive (surface thickness 8mm Hardness: HRC93.1) was arranged on a rubber sheet at intervals of 1 mm and bonded with an epoxy adhesive to produce a grindstone sheet.
On the other hand, a phenolic resin-impregnated paper tube (outer diameter: 86 mm, inner diameter: 76 mm) is prepared as a core tube, a sponge urethane resin sheet having a thickness of 50 mm is wound around the outer periphery, and the epoxy resin is attached to the core tube, Furthermore, the outer periphery was covered with a fiber-reinforced rubber sheet cylinder. And the grinding wheel sheet mentioned above was wound and adhere | attached on it, and the grinding roll of the comparative example was assembled.

The copper foil surface of the copper-clad laminate having a width of 340 mm, a length of 300 mm, and a thickness of 1 mm was ground using the three types of cylindrical grindstones under the following conditions.
Test equipment: Marugen Iron Works polishing machine. Wheel peripheral speed: 942 m / min (rotational speed 200 rpm). Work feed speed: 2 m / min. Oscillation: 350 cpm. Load: + 2.0A.
The surface roughness of the copper foil after grinding was measured, and the presence or absence of scratches was observed. The results are shown in Table 2.

As is clear from Table 2, when grinding is performed with a grinding roll using the resin grindstones of Examples 1 and 2, scratches do not occur, and Ra and Ry values are extremely small, and a good ground surface can be processed. .
In addition, in the case of the grinding roll of the example, its production is extremely easy as compared with the grinding roll of the comparative example, and therefore it can be produced at a low cost, and the roll for substrate grinding including its excellent performance is included. As such, the industrial value is great.

Example 3
Six copper-clad laminates having a dimension and shape of 540 mm in length, 540 mm in width, and 1.2 mm in thickness and having a total of 190,000 through-holes with a hole diameter of 0.3 mm on the surface were prepared.
And the surface grinding of the copper clad laminated board was performed using the grinding roll of Example 1. FIG.
For comparison, a similar test was performed using a polishing buff.
As a result, when the grinding roll of Example 1 was used, no foreign matter was found in the through hole. However, when a polishing buff was used, “buffing” was observed in 11 out of a total of 1.14 million (190,000 × 6) through holes.

Even if the material to be ground is soft, the surface of the resin grindstone of the present invention can be a ground surface having excellent flatness and specularity without causing scratches.
This resin grindstone is extremely useful when used, for example, for surface grinding of circuit boards and mirror polishing of seal members of vacuum devices.
In addition, various materials used in the semiconductor field and the optical field, for example, silicon carbide, silicon nitride, alumina, BK7 optical glass, SF13 optical glass, crystallized glass, quartz glass, cermet, ferrite, silicone wafer, and other brittle materials It can be used as a tool for a fixed abrasive processing method when a member made of

  Moreover, the cylindrical grinding roll of the present invention using this resin grindstone can be manufactured very easily as compared with the conventional grinding roll, and even when the resin grindstone is worn, for example, by lathe processing. The worn resin grindstone can be easily ground and removed, and a new resin grindstone can be fixed to the outer periphery of the exposed metal tube and reused.

It is a fragmentary sectional view of the soft resin grindstone of the present invention. It is sectional drawing which shows the cross-section of the grinding action part in the cylindrical grinding roll of this invention. It is a perspective view for demonstrating an example of the manufacturing method of the grinding action part in the cylindrical grinding roll of this invention. It is sectional drawing which shows the cross-section of the conventional cylindrical grinding roll. It is a perspective view which shows the conventional cylindrical grinding roll.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Resin binder 2 Abrasive grain 3 Inorganic filler 4 Independent pore 5 Core pipe 6 Elastic body 7 Support body 7a Porous elastic body layer 7b Dense elastic body layer 7c Elastic body layer 8 Metal tube 9 Rubber sheet 10 Grinding stone piece 11 Metal Tube 11a Peripheral surface 12 of metal tube 11 Soft resin grindstone 13 Bottomed cylindrical mold

Claims (10)

  Abrasive grain 5-25% by volume, inorganic filler 3-12% by volume, pores 50-500 μm independent pores 5-15% by volume, the balance is made of resin binder, and the surface hardness of the resin binder is Shore D value A soft resin grindstone characterized by being 20 or more.   The soft resin grindstone according to claim 1, wherein the resin binder is made of a cured epoxy resin. The abrasive grain is at least one powder selected from the group consisting of Al ₂ O ₃ , SiO ₂ , CeO, ZrO ₂ , MnO ₂ , Cr ₂ O ₃ , cBN, SiC, diamond, and sapphire. 2 soft resin grindstone.   The soft resin grindstone according to claim 3, wherein the abrasive grains have a maximum particle size of 500 μm.   The soft resin grindstone according to any one of claims 1 to 4, wherein the inorganic filler is at least one selected from the group of carbon whisker, alumina whisker, silica whisker, magnesium whisker, and aluminum borate whisker.   A cylindrical grinding roll comprising a grinding action portion comprising a cylindrical metal tube and the soft resin grindstone of any one of claims 1 to 5 fixed to the outer peripheral surface of the cylindrical metal tube. .   The cylindrical grinding roll according to claim 6, wherein the cylindrical metal tube is made of Al or an Al alloy.   The sheet of the soft resin grindstone according to any one of claims 1 to 5 is wound around an outer peripheral surface of the cylindrical metal tube via an adhesive or a velcro tape, and the sheet is fixed to the outer peripheral surface of the cylindrical metal tube. The manufacturing method of the cylindrical grinding roll characterized by forming the grinding action part which is.   A cylindrical metal tube is coaxially arranged in a bottomed cylindrical mold, and a liquid resin and an inorganic filler are formed in a gap formed by the inner peripheral surface of the cylindrical mold and the outer peripheral surface of the cylindrical metal tube. The cylindrical metal tube by injecting a uniform mixture of a hardener, abrasives of the liquid resin, and an independent pore forming source and then heating to cure the mixture, and then releasing the cylindrical mold A method for producing a cylindrical grinding roll, comprising forming a grinding action portion in which a cured product of the mixture is fixed on an outer peripheral surface of the cylindrical grinding roll.   The method for producing a cylindrical grinding roll according to claim 9, wherein the independent pore forming source is a foaming agent or an organic or inorganic balloon.

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