JP5350526B2 - Manufacturing method of backgrinding grinding tape and backgrinding grinding tape manufacturing apparatus - Google Patents

Description

  The present invention, when manufacturing grinding tape for semiconductor wafer backgrinding from molten resin, dramatically reduces the fish eye by efficiently filtering and refining gel components contained in the molten resin that cause fish eye. The present invention relates to a method for manufacturing a backgrinding grinding tape and a manufacturing apparatus for the same.

  Conventionally, when a molten resin extruded from a resin extruder is supplied to a resin body molding apparatus and resin bodies of various forms such as resin pellets and resin films are manufactured, the resin extruder and the resin body molding apparatus are connected. A filter that purifies and purifies molten resin is disposed in the resin supply path, and by performing filtration and purification of the molten resin through such a filter, fish eyes in a resin body molded by a resin body molding apparatus are reduced. Various resin manufacturing methods configured as described above have been proposed.

  For example, Japanese Patent Application Laid-Open No. 2003-342318 discloses a granulation extruder for granulating and forming a molten resin while maintaining the molten resin temperature at least 230 ° C. or higher when producing an ethylene copolymer resin by a high pressure polymerization method. Describes a method for producing an ethylene copolymer resin provided with a fine filter.

  As the fine filter used in the method for producing the ethylene copolymer resin, for example, a wire mesh filter of 200 mesh or more and a metal fiber sintered filter having a filtration accuracy of 50 μm or more are used.

JP 2003-342318 A (Page 1 to Page 4, FIG. 1)

  However, the wire mesh filter and the metal fiber sintered filter constituting the fine filter used in the method for producing the ethylene copolymer resin described in Patent Document 1 are all used alone. In such a case, the cross-linked gel that causes fish eyes is filtered and refined based on the characteristics of each filter, but the filtration and purification capacity is limited to the filtration and purification capacity of the wire mesh filter or metal fiber sintered filter alone. The

  According to this, depending on the fine filter used in the method for producing the ethylene copolymer resin, it is not possible to expect a dramatic improvement in the filtration and purification capacity, and it is not possible to further reduce the fish eye. .

  The present invention has been made in order to solve the problems in the prior art, and uses a filter in which a metal mesh and a metal nonwoven fabric are laminated, and has a wide range and efficiency of gel in molten resin causing fish eyes. An object of the present invention is to provide a backgrinding grinding tape manufacturing method capable of manufacturing a backgrinding grinding tape with significantly reduced fish eyes, and an apparatus for manufacturing the same.

  In order to achieve the above object, a manufacturing method of a backgrinding grinding tape according to claim 1 supplies a molten resin extruded at a high pressure to a filter and manufactures a backgrinding grinding tape from the molten resin that has passed through the filter. In the method of manufacturing a backgrinding grinding tape, the filter has two wire meshes, and the wire mesh disposed on the inner and downstream sides of the two wire meshes is formed with a mesh size of 500 mesh or more, and the wire mesh. A metal nonwoven fabric filter is provided which is laminated on a wire mesh filter on the downstream side of the filter and formed from a metal nonwoven fabric having a filtration accuracy of 60 μm or less.

  A backgrinding grinding tape manufacturing method according to a second aspect of the present invention is the backgrinding grinding tape manufacturing method according to the first aspect, wherein the molten resin is an ethylene copolymer resin.

  The backgrinding grinding tape manufacturing method according to claim 3 is the backgrinding grinding tape manufacturing method according to claim 2, wherein the ethylene copolymer resin is an ethylene vinyl acetate copolymer resin. .

  An apparatus for producing a grinding tape for back grinding according to claim 4 comprises: a resin extruder; a resin supply path for guiding and supplying the molten resin extruded from the resin extruder; and the molten resin guided and supplied from the resin supply path A grinding tape molding device for back grinding that molds a grinding tape for back grinding from, and a filter that is disposed in the resin supply path and that performs filtration purification of the molten resin extruded from the resin extruder, There are two wire meshes, and the wire mesh disposed on the downstream side of the two wire meshes is laminated to the wire mesh filter formed in a mesh size of 500 mesh or more, and downstream of the wire mesh filter, and the filtration accuracy is improved. A metal nonwoven fabric filter formed from a metal nonwoven fabric of 60 μm or less is provided.

In the method for producing a backgrinding grinding tape according to claim 1, the filter for filtering and purifying the molten resin has two wire meshes, and the wire mesh disposed on the inner and downstream sides of the two wire meshes has a mesh size of 500 mesh or more. A metal mesh filter formed on the metal mesh filter on the downstream side of the metal mesh filter and formed from a metal nonwoven fabric having a filtration accuracy of 60 μm or less. When the molten resin passes through the filter, Foreign matter such as fibers and dust contained in the molten resin is collected through a wire mesh formed in a mesh size of 500 mesh or more reinforced by one wire mesh of two wire meshes constituting the wire mesh filter. The cross-linked gel is subdivided, and then the wire mesh filter is passed through a metal nonwoven fabric filter formed from a metal nonwoven fabric with a filtration accuracy of 60 μm or less. The cross-linked gel subdivided by the catalyst is efficiently collected.
Thus, since the filter is configured by laminating the wire mesh filter and the metal nonwoven fabric filter, the filtration effect of the metal mesh filter and the filtration effect of the metal nonwoven fabric filter are synergistically expressed, and the fisheye The cross-linked gel in the molten resin that is the cause can be filtered and purified in a wide range and efficiently, and a backgrinding grinding tape with significantly reduced fish eyes can be produced.

  Further, as described in claim 2, an ethylene copolymer resin is used as a molten resin used in the production method, and in particular, as an ethylene copolymer resin as described in claim 3, Ethylene vinyl acetate copolymer resin is desirable.

In the grinding machine for back grinding according to claim 4, the resin extruder, the resin supply passage for guiding and supplying the molten resin extruded from the resin extruder, and the molten resin guided and supplied from the resin supply passage are used as the back. A grinding machine for forming a grinding tape for grinding and a grinding machine for forming a grinding tape for grinding, and a filter disposed in the resin supply path for filtering and purifying the molten resin extruded from the resin extruder, the filter having two wire meshes. The wire mesh disposed on the inner and downstream sides of the two wire meshes is composed of a wire mesh filter formed to a mesh size of 500 mesh or more and a metal nonwoven fabric having a filtration accuracy of 60 μm or less laminated on the wire mesh filter on the downstream side of the wire mesh filter. It has a formed metal nonwoven fabric filter, and when the molten resin passes through the filter, first of the two wire meshes constituting the wire mesh filter Foreign materials such as fibers and dust contained in the molten resin are collected through the wire mesh formed in a mesh size of 500 mesh or more reinforced by one wire mesh, and the cross-linked gel is subdivided. Thus, the cross-linked gel subdivided by the wire mesh filter is efficiently collected through a metal nonwoven fabric filter formed from a metal nonwoven fabric having a filtration accuracy of 60 μm or less.
Thus, since the filter is configured by laminating the wire mesh filter and the metal nonwoven fabric filter, the filtration effect of the metal mesh filter and the filtration effect of the metal nonwoven fabric filter are synergistically expressed, and the fisheye The cross-linked gel in the molten resin that is the cause can be filtered and purified in a wide range and efficiently, and a backgrinding grinding tape with significantly reduced fish eyes can be produced.

It is explanatory drawing which shows typically the resin film manufacturing apparatus which manufactures the resin film used as a grinding tape for back grinding concerning this embodiment. It is a schematic cross section which shows typically the structure of the filter incorporated in a filtering unit. The number of fish eyes counted for the ethylene vinyl acetate copolymer resin film formed by variously changing the mesh size of the metal mesh in the wire mesh filter and the filtration accuracy of the metal nonwoven fabric filter is a matrix of the mesh size of the metal mesh and the filtration accuracy of the metal nonwoven fabric. It is explanatory drawing shown by. The number of fish eyes counted with a resin film molded without using a filter, and the number of fish eyes counted with a resin film formed by purifying molten resin using only a wire mesh filter It is explanatory drawing which shows.

Hereinafter, based on the embodiment which materializes the present invention about the resin film used for the manufacturing method of a resin film used as a grinding tape for back grinding concerning the present invention, a manufacturing device, these manufacturing methods, and a manufacturing device This will be described in detail with reference to the drawings.
First, the resin film manufacturing apparatus which manufactures the resin film used as the grinding tape for back grinding which concerns on this embodiment is demonstrated easily based on FIG. FIG. 1 is an explanatory view schematically showing a resin film manufacturing apparatus.

In FIG. 1, the resin film manufacturing apparatus 1 basically includes an extruder 2, a filtering unit 6, and a die 4.
Here, the extruder 2 melts an ethylene copolymer resin, for example, an ethylene vinyl acetate copolymer resin, and extrudes the molten resin at a high pressure while purging nitrogen gas.

  A conduit 3 is connected to the extruder 2, and the conduit 3 is connected to a filtering unit 6. The filtering unit 6 is connected to the die 4 via a conduit 3.

  In the above-described configuration, the melted ethylene vinyl acetate copolymer resin extruded from the extruder 2 is supplied to the filtering unit 6 through the conduit 3, and the ethylene vinyl acetate copolymer resin is filtered and purified by the filtering unit 6. Thereafter, the ethylene vinyl acetate copolymer resin is supplied to the die 4 through the conduit 3.

  The ethylene vinyl acetate copolymer resin extruded while purging nitrogen gas with the die 4 is supplied to a film molding machine (not shown), and the ethylene vinyl acetate copolymer having a predetermined uniform film thickness by the film molding machine. It is formed into a polymer resin film.

  Here, the structural example of the filtering unit 6 is demonstrated based on FIG. FIG. 2 is a schematic cross-sectional view schematically showing a configuration of a filter built in the filtering unit. In FIG. 2, the upper side shows the extruder 2 side (upstream side), and the lower side shows the die 4 side (downstream side). As shown in FIG. 2, the filter 5 is configured by laminating a wire mesh filter 8, a metal nonwoven fabric filter 9, and a wire mesh filter 10 from the upstream side.

  Here, the upstream wire mesh filter 8 includes two wire meshes 8A and 8B having different mesh sizes. These wire meshes 8A and 8B are formed with regular openings corresponding to the respective mesh sizes. For example, when the wire mesh 8A has a mesh size 50 and the wire mesh 8B has a mesh size 500, The wire mesh 8A mainly functions to reinforce the wire mesh 8B so that the wire mesh 8B does not deform. The wire mesh 8B collects foreign matters such as fibers and dust contained in the melted ethylene-vinyl acetate copolymer resin. The caustic large cross-linked gel is subdivided according to its mesh size.

  The number of wire meshes constituting the upstream wire mesh filter 8 is not limited to two, and the number of wire meshes can be arbitrarily set as required. At this time, the wire mesh with the largest mesh size (small regular opening size) collects foreign matters such as fibers and dust contained in the molten ethylene-vinyl acetate copolymer resin, The caustic large cross-linked gel is subdivided according to its mesh size. As the wire mesh, those having various mesh sizes are used. For example, 100 mesh, 200 mesh, 300 mesh, 400 mesh, 500 mesh, and 635 mesh wire mesh are generally easily available and widely used. .

  Further, the metal nonwoven fabric filter 9 is a metal fiber sintered filter formed by sintering metal fibers such as stainless copper fibers, and is formed by a large number of spaces having irregular shapes formed therein. It acts to collect a cross-linked gel that is shaped and flexible. Some metal nonwoven fabric filters 9 have various filtration accuracies depending on the size of the irregular space. For example, metal nonwoven fabric filters with filtration accuracy of 80 μm, 60 μm, and 40 μm are generally easily available and are widely used.

  In addition, the number of the metal nonwoven fabric filters 9 is not limited to one, and can be an arbitrary number as necessary. Also in this case, as in the case of the wire mesh filter 8, the metal nonwoven fabric filter having the highest filtration accuracy (small amorphous space) is irregularly formed by a large number of irregular spaces formed therein. And collects the crosslinked gel having flexibility.

  The wire mesh filter 10 disposed on the downstream side of the metal nonwoven fabric filter 9 is composed of a wire mesh having the same configuration as the wire mesh filter 8, and is composed of two wire meshes 10A and 10B having different mesh sizes. Yes. These metal meshes 10A and 10B are formed with regular openings corresponding to the respective mesh sizes. In general, however, the metal nonwoven fabric is used so as to prevent deformation of the metal nonwoven fabric filter 9 and maintain proper filtration accuracy. It is provided to reinforce the filter 9.

Subsequently, the mesh size of the wire mesh filter 8 and the filtration accuracy of the metal nonwoven fabric filter 9 in the filter 5 are variously changed to perform filtration purification of the melted ethylene-vinyl acetate copolymer resin extruded from the extruder 2. A result of forming a resin film from an ethylene vinyl acetate copolymer resin through a die 4, a film forming roller, and a film forming machine and counting the number of fish eyes remaining on the resin film will be described with reference to FIG. FIG. 3 shows the number of fish eyes counted for an ethylene vinyl acetate copolymer resin film formed by variously changing the mesh size of the wire mesh in the wire mesh filter and the filtration accuracy of the metal nonwoven fabric filter. It is explanatory drawing shown with the matrix of filtration accuracy. The horizontal column in FIG. 3 indicates the mesh size of the wire mesh, and the vertical column indicates the filtration accuracy of the metal nonwoven fabric. The number of fish eyes is a laser type fish eye counter (FS-5 manufactured by OCS, measurement sensitivity: level 75, measurement conditions: line speed 4 m / min, detection width 60 mm, film thickness 50 μm, measurement time 15 min, measurement. Measured at an area of 3.6 m ² , N = 2), 1
The number of fish eyes per m ² was obtained.

In FIG. 3, the mesh size value of the wire mesh having the largest mesh size among the wire meshes constituting the wire mesh filter 8 is shown in the horizontal column. As the wire mesh used in this embodiment, six types of wire meshes of 100 mesh, 200 mesh, 300 mesh, 400 mesh, 500 mesh, and 635 mesh were used. In FIG. 3, three types of metal nonwoven fabric filters having filtration accuracy of 80 μm, 60 μm, and 40 μm were used as the metal nonwoven fabric filters used in the present embodiment.
In each column indicated by the matrix of mesh size and filtration accuracy, the value in the upper row is the sum of the number of fish eyes less than 50 μm measured per 1 m ² and the number of fish eyes greater than 50 μm. Indicates a number. Further, the middle value indicates the number of measured 50μm or less fisheyes in 1 m ² per. Further, the lower value indicates the number of fish eyes of 50 μm or more measured per 1 m ² .

By the way, when the resin supply conduit 3 is not provided with a filter, a melted ethylene vinyl acetate copolymer resin is supplied to the die 4 and a resin film is formed via a film forming roller and a film forming machine. the, as shown in FIG. 4, the number of measured 50μm or less fish eyes Fish eyes counter 6413 per 1 m ^2, the number of more fisheyes 50μm is 1195 per 1 m ^2, 1 m ² per The total number of fish eyes was 7608.

In addition, a conventional metal mesh filter layered on the conduit 3 (maximum mesh size: 500 mesh) is interposed, and a melted ethylene vinyl acetate copolymer resin is supplied to the die 4 so that a film forming roller and a film forming machine are provided. when molding the resin film through, as shown in FIG. 4, the number of the following fish eye measured 50μm which in fisheye counter 4362 per 1 m ^2, the number of more fisheyes 50μm is 1 m ² per There were 877, and the total number of fish eyes per 1 m ² was 5239.

Here, as described above, the ethylene-vinyl acetate copolymer resin film produced by the resin film production apparatus 1 can be used for various applications, but particularly as a grinding tape for back grinding of semiconductor wafers. If used, fish eyes with a certain height or more may cause deformation or cracking of the wafer, and as the number of fish eyes increases, fish eyes with a certain height or more are generated. Therefore, the total number of fish eyes is preferably suppressed to 4600 or less.
Even if the total number of fish eyes exceeds 4600, the ethylene-vinyl acetate copolymer resin film can be applied to various surface protective films according to the purpose and characteristics of use.

In FIG. 3, when the mesh size of the wire mesh filter 8 is 100 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 80 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 4648 per 1 m ² . The number of fish eyes of 50 μm or more was 998 per 1 m ² , and the total number of fish eyes per 1 m ² was 5546.

Further, when the mesh size of the wire mesh of the wire mesh filter 8 is 100 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 60 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 5333 per 1 m ² , The number of fish eyes of 50 μm or more was 996 per 1 m ² , and the total number of fish eyes per 1 m ² was 6329.

When the mesh size of the wire mesh filter 8 is 200 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 60 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 5060 per 1 m ² , The number of fish eyes of 50 μm or more was 982 per 1 m ² , and the total number of fish eyes per 1 m ² was 6042.

In addition, when the mesh size of the wire mesh of the wire mesh filter 8 is 300 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 60 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 4788 per 1 m ² , The number of fish eyes of 50 μm or more was 966 per 1 m ² , and the total number of fish eyes per 1 m ² was 5754.

Further, when the mesh size of the wire mesh of the wire mesh filter 8 is 300 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 40 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 3983 per 1 m ² , The number of fish eyes of 50 μm or more was 779 per m ² , and the total number of fish eyes per 1 m ² was 4762.

When the mesh size of the wire mesh filter 8 is 400 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 60 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 4286 per 1 m ² , The number of fish eyes of 50 μm or more was 1022 per 1 m ² , and the total number of fish eyes per 1 m ² was 5308.

Further, when the mesh size of the wire mesh filter 8 is 500 mesh, and the filtration accuracy of the metal nonwoven fabric filter 9 is 80 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 4139 per 1 m ² , The number of fish eyes of 50 μm or more was 807 per 1 m ² , and the total number of fish eyes per 1 m ² was 4946.

In addition, when the mesh size of the metal mesh filter 8 is 500 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 60 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 3830 per 1 m ² , The number of fish eyes of 50 μm or more was 770 per 1 m ² , and the total number of fish eyes per 1 m ² was 4600.

In addition, when the mesh size of the wire mesh filter 8 is 500 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 40 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 3828 per 1 m ² , The number of fish eyes of 50 μm or more was 742 per 1 m ² , and the total number of fish eyes per 1 m ² was 4570.

Further, when the mesh size of the wire mesh filter 8 is 635 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 80 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 4819 per 1 m ² , The number of fish eyes of 50 μm or more was 921 per 1 m ² , and the total number of fish eyes per 1 m ² was 5740.

When the mesh size of the wire mesh filter 8 is 635 mesh, and the filtration accuracy of the metal nonwoven fabric filter 9 is 60 μm, the number of fish eyes of 50 μm or less measured by the fish eye counter is 3785 per 1 m ² , The number of fish eyes of 50 μm or more was 785 per 1 m ² , and the total number of fish eyes per 1 m ² was 4570.

As described above, in the resin film manufacturing apparatus 1 according to this embodiment, the filter 5 for filtering and purifying the molten ethylene-vinyl acetate copolymer resin laminates the wire mesh filter 8 and the metal nonwoven fabric filter 9. When the molten ethylene vinyl acetate copolymer resin passes through the filter 5, first, foreign matters such as fibers and dust contained in the molten ethylene vinyl acetate copolymer resin are collected through the wire mesh filter 8. At the same time, the cross-linked gel is subdivided, and then the cross-linked gel subdivided by the wire mesh filter 8 through the metal nonwoven fabric filter 9 is efficiently collected.
Thus, since the filter 5 is formed by laminating the wire mesh filter 8 and the metal nonwoven fabric filter 9, the filtering effect of the wire mesh filter 8 and the filtering effect of the metal nonwoven fabric filter 9 are expressed synergistically. Thus, the cross-linked gel in the molten resin that causes fish eyes can be filtered and purified in a wide range and efficiently, and a resin film with markedly reduced fish eyes can be produced.

In addition, when the ethylene vinyl acetate copolymer resin film produced by the resin film production apparatus 1 is used as a grinding tape for back grinding of a semiconductor wafer, the total number of fish eyes is used to prevent deformation and cracking of the wafer. Is desirably 4600 or less. When the mesh size of the wire mesh filter 8 is 500 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 60 μm, the total number of fish eyes per 1 m ² The number is 4600, and when the mesh size of the metal mesh filter 8 is 500 mesh and the filtration accuracy of the metal nonwoven fabric filter 9 is 40 μm, the total number of fish eyes per 1 m ² is 4570. In addition, the mesh size of the wire mesh of the wire mesh filter 8 635 mesh, and, when the filtration accuracy of the metal nonwoven fabric filter 9 is 60μm, the total number of fish eyes per 1 m ² is because it is 4570 pieces, the mesh size of the wire mesh wire mesh filter 8 500 mesh or higher And if the filtration precision of the metal nonwoven fabric filter 9 is 60 micrometers or less, the ethylene vinyl acetate copolymer resin film which can be used as a grinding tape for back grinding of a semiconductor wafer can be manufactured.

It should be noted that the present invention is not limited to the above-described embodiment, and various improvements and modifications can be made without departing from the scope of the present invention.
For example, in the resin film manufacturing apparatus 1 according to the above embodiment, after the molten resin extruded from each extruder 2 is subjected to filtration purification of the molten resin through the filter 5 in the process of conveying the resin through the resin supply pipe 3. The resin film is formed through a die 4, a film forming roller, and a film forming machine. The molten resin that has been filtered and purified through a filter 5 is supplied to a pelletizer (single-axis granulating extruder). And you may comprise so that a resin pellet may be manufactured with a pelletizer.

  Even in such a case, as described above, the filtration effect by the wire mesh filter 8 and the filtration effect of the metal nonwoven fabric filter 9 are synergistically expressed, and the cross-linked gel in the molten resin causing fish eyes is widespread. In addition, since it is efficiently filtered and refined, resin pellets with significantly reduced fish eyes can be produced. Therefore, even when the resin pet manufactured as described above is used to form a film, as described above, it is possible to manufacture a resin film with markedly reduced fish eyes.

DESCRIPTION OF SYMBOLS 1 Resin film manufacturing apparatus 2 Extruder 3 Conduit 4 Dice 5 Filter 6 Filtering unit

Claims (4)

In the manufacturing method of the backgrinding grinding tape, the molten resin extruded at high pressure is supplied to the filter, and the backgrinding grinding tape is manufactured from the molten resin that has passed through the filter.
The filter is
In the manufacturing method of the backgrinding grinding tape, the molten resin extruded at high pressure is supplied to the filter, and the backgrinding grinding tape is manufactured from the molten resin that has passed through the filter.
The filter is
The wire mesh that has two wire meshes and is arranged on the inner downstream side of the two wire meshes is a wire mesh filter formed in a mesh size of 500 mesh or more,
A method for producing a backgrinding grinding tape comprising a metal nonwoven fabric filter laminated on a wire mesh filter downstream of the wire mesh filter and formed of a metal nonwoven fabric having a filtration accuracy of 60 μm or less.   The method for producing a grinding tape for back grinding according to claim 1, wherein the molten resin is an ethylene copolymer resin.   The method for producing a grinding tape for back grinding according to claim 2, wherein the ethylene copolymer resin is an ethylene vinyl acetate copolymer resin. A resin extruder;
A resin supply path for guiding and supplying the molten resin extruded from the resin extruder;
Back grinding grinding tape molding apparatus for molding a back grinding grinding tape from the molten resin guided and supplied from the resin supply path;
A filter that is disposed in the resin supply path and that performs filtration purification of the molten resin extruded from the resin extruder;
The filter is
The wire mesh that has two wire meshes and is arranged on the inner downstream side of the two wire meshes is a wire mesh filter formed in a mesh size of 500 mesh or more,
An apparatus for producing a grinding tape for back grinding, comprising a metal nonwoven fabric filter laminated on a wire mesh filter downstream of the wire mesh filter and formed from a metal nonwoven fabric having a filtration accuracy of 60 μm or less.

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