JP5147214B2 - Manufacturing method of molded products - Google Patents

Description

  The present invention relates to a method for manufacturing a molded article.

Conventionally, semiconductors have been used in various fields including computers. This semiconductor is manufactured through a wafer manufacturing process and a chip manufacturing process.
In the wafer manufacturing process, a silicon single crystal ingot is cut out, and, for example, a silicon wafer having a diameter of 5 to 12 inches is manufactured. The silicon wafer is then polished and the front and back surfaces are mirror surfaces. Thereafter, transistors, wirings, and the like are arranged on the silicon wafer.
In the chip manufacturing process, the wafer manufactured in the wafer manufacturing process is diced and separated into chips (see Patent Document 1).

JP 2003-206175 A (page 2, [0004])

  In each semiconductor manufacturing process, scraps such as silicon wafer cutting scraps, grinding scraps, and polishing scraps are generated. This waste contains waste liquid and silicon, but at present, this waste is disposed of as waste. However, from the viewpoint of environmental protection and cost reduction for disposal, it is desired to reuse silicon contained in the waste.

  The objective of this invention is providing the manufacturing method of the molded article which can recycle | reuse the silicon | silicone in scraps, such as a cutting scrap of a silicon wafer, a grinding scrap, a polishing scrap, which arises in each manufacturing process of a semiconductor.

The method for producing a molded product of the present invention is a method for producing a molded product containing silicon,
A silicon-containing scrap generated in any one of the semiconductor manufacturing processes of silicon ingot cutting, silicon wafer grinding, polishing, and silicon wafer dicing is mixed with a resin-based binder material so that the silicon content is 50. A molding material production process for producing a molding material of mass% or more and 70 mass% or less,
A heating press molding step of molding the molding material manufactured in the molding material manufacturing step under heating and molding a molded product; and
A cooling step of cooling and curing the molded product formed in the heating press step,
The molding material manufacturing process includes:
A primary kneading step of kneading and curing the resin-based binder material and the silicon-containing waste, and then pulverizing to obtain a primary kneaded material;
Kneading the primary mixing materials and the resin-based binder materials, allowed to air dry, and a secondary kneading step to obtain the molding material by crushing,
The resin binder material is a varnish containing a phenol resin obtained in a varnish production process .

Here, the molded product can be used as a slicing table used when a silicon ingot is cut with a wire saw or the like, or as another jig for processing a silicon wafer.
In addition, waste generated in the semiconductor manufacturing process is generated as sludge containing moisture generated in any of the processes of silicon ingot cutting, silicon wafer grinding, polishing, and silicon wafer dicing. It can be obtained as a body.
Furthermore, as the resin binder material, various materials such as phenol, xylene, furan, and melamine can be used. However, when used as a jig such as a slicing table, alkali cleaning is performed. It is particularly preferable to adopt it.

When the content of at least one of silicon and silica in the molding material manufacturing process is less than 50% by mass, the waste utilization rate is low and the recyclability is poor.
In addition, when the molded product is a slicing table for cutting an ingot, if the content of at least one of silicon and silica is 50% by mass or more, the hardness of the ingot and the slicing table can be made substantially the same. Even if cut simultaneously, the unevenness of cutting due to the difference in hardness does not occur, and the flatness of the cutting surface of the silicon wafer can be improved.
On the other hand, when the content of at least one of silicon and silica exceeds 70% by mass, it becomes brittle and cannot be a molded product having sufficient strength.

According to the present invention, a molding material containing silicon and silica contained in scrap generated in the semiconductor manufacturing process and a resin-based binder material is hot-molded and pressed to form a molded product, and then cooled and cured to form a molded product. Therefore, waste generated during semiconductor manufacturing can be reused as a molded product.
Moreover, since content of the waste in a molding material is 50 mass% or more and 70 mass% or less, silicon | silicone can be reliably couple | bonded with a binder material. Thereby, it can prevent that a molded article becomes weak.
In particular, by forming the molded product as a processing jig when processing a silicon wafer, when cutting the processing jig along with the cutting of a silicon ingot or silicon wafer, the silicon-containing waste is included in the above content. By using a molded product, the hardness can be substantially the same as that of silicon to be cut, so even if cutting is performed across the cutting object and the processing jig, the cutting object can be cut without deviation. .

Further, in the present invention, the pre-Symbol varnish manufacturing step by dissolving the phenolic resin in a volatile solvent, to produce the varnish, kneading the waste containing the silicon and the varnish in the primary kneading step, it is cured It was followed to obtain the primary kneaded material was pulverized, the kneaded at secondary kneading step and the varnish and the primary mixing materials, allowed to air dry, it is preferable to obtain the molding material is pulverized.
In this invention, since the resin contained in the binder material is a phenol resin, the acid resistance and alkali resistance of the molded product can be improved.
Further, since the phenol resin is dissolved in a volatile solvent to form a varnish, the fluidity is high and kneading can be easily performed when kneading with silicon.

Furthermore, in the present invention, in the cooling step, it is preferable to cool by tightening an outer peripheral surface of the molded product.
In the present invention, since the cooling is performed by tightening the outer peripheral surface of the molded product in the cooling process, even if cooling unevenness occurs in the molded product, the molded product is restrained by tightening and warping occurs. Can be prevented.

Moreover, in this invention, it is preferable to provide the heat processing process of tightening the outer peripheral surface of the molded article cooled at the said cooling process, and heat-processing.
In the present invention, since the molded product after cooling is annealed by heat treatment, the internal stress of the molded product is relaxed, and deformation of the molded product such as warpage is more reliably prevented. Can do.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[1] Configuration of Multi-Wire Saw FIG. 1 shows a multi-wire saw system for cutting a silicon ingot 3 using a slicing base 5 according to an embodiment of the present invention.
In the multi-wire saw system, a single thin wire (piano wire) is used as a saw wire 1, wound around a number of grooves provided in a plurality of wire guide rollers 2, and the saw wire 1 is moved in one direction or reciprocated. A cutting liquid (slurry liquid) 7 in which abrasive grains are dispersed is moved by pressing the silicon ingot 3 to be cut bonded to the slicing base 5 provided on the base 4 with the adhesive 6, and the saw wire 1 and the ingot 3. The contact portion is continuously supplied and cut.
The surface of the slicing base 5 is molded so as to be applied to the surface shape of the ingot 3. If the ingot 3 is cylindrical as illustrated, the bonding surface of the slicing base 5 is formed in a concave shape in an arc shape. The ingot 3 is not limited to a cylindrical shape, and may have an appropriate shape such as a quadrangular prism shape or an octagonal prism shape.

The adhesive surface of the slicing base 5 is formed with a satin finish, a concave line, etc. to strengthen the adhesive force with the adhesive, so that the adhesive remains on the ingot 3 side when separated from the ingot 3. This is preferable in the sense that the possibility of doing so can be reduced.
Ingot 3 is a type in which a large number of saw wires 1 are pushed down and pressed against saw wire 1 as shown in FIG. 1, and ingot 3 is pushed up and pressed in a 180 ° inverted state, It may be of a type that is pressed in the lateral direction after being rotated by 90 °.

1 shows an example in which three wire guide rollers 2 are used, but there may be two wire guide rollers or four or more wire guide rollers.
Further, the cutting liquid 7 may be supplied from both sides of the ingot 3 particularly when the saw wire 1 reciprocates, or from the side of the saw wire 1 toward the ingot 3 (from bottom to top in FIG. 1). Can be supplied.
The saw wire 1 is pressed against the ingot 3 to apply a pressing force, and the ingot 3 is cut by a grinding action via the abrasive grains. The cutting speed of the ingot 3 is determined by the pressing force and the speed of the saw wire 1.
If the pressing force is large, the tension of the saw wire 1 increases, and if it is too large, the saw wire 1 may be broken.

Although the illustration of the saw wire 1 acting on the ingot 3 in the middle of cutting is omitted, a cutting line having a curved shape is drawn inside the ingot 3 and is linear between the ingot 3 and the wire guide roller 2.
In order to completely cut the ingot 3, the slicing base 5 is partly cut along with the workpiece to be cut, and the ingot 3 is sliced with the adhesive 6 after being sliced. Keeps on.

[2] Detailed Configuration of Cutting Object Including Slice Table 5 FIG. 2 shows a slice table 5 and a side protector 8 as molded products to be manufactured by the method for manufacturing a molded product of the present invention.
The slice table 5 is a table that supports the ingot 3 when the substantially cylindrical silicon ingot 3 is cut. The slicing base 5 has a substantially rectangular plane shape, and an arc-shaped concave portion 11 is formed on the upper surface of the slicing base 3 along the longitudinal direction, and the ingot 3 is placed and fixed by an adhesive. In addition, the diameter of the recessed part 11 is set according to the diameter of the ingot 3, for example, is 150 mm, 200 mm, or 300 mm.
The slicing base 5 has a length L that is substantially the same as the length of the ingot 3 so that the ingot 3 can be adhered and held even after slicing, and the width W is larger than the diameter of the ingot 3. Small dimensions.

  The side protector 8 has a disk shape and is attached to both end faces of the ingot 3 to prevent the silicon wafers at both ends of the ingot 3 from falling when the ingot 3 is cut. The diameter of the side protector 8 is set according to the diameter of the ingot 3, and is set to 150 mm, 200 mm, or 300 mm, for example. In this embodiment, since the ingot 3 is for a semiconductor wafer, the shape of the side protector 8 is a disk shape. However, when the oriental flat surface is formed, the side protector 8 may be a semicircular shape. In the case of an ingot for manufacturing a panel or the like, a rectangular shape may be used.

The slicing base 3 and the side protector 8 contain silicon contained in scrap generated in the semiconductor manufacturing process and a resin (for example, phenol resin) that is a binder material.
The semiconductor manufacturing process consists of a wafer manufacturing process and a chip manufacturing process. In the wafer manufacturing process, a silicon single crystal is grown by the Czochralski method (CZ method) or the floating zone melting method (FZ method). Ingot 3 is manufactured.
And the outer periphery of this ingot 3 is ground with a cylindrical grinder etc., and the shape of an outer peripheral surface is prepared. Next, the silicon single crystal ingot 3 is cut out, and, for example, a silicon wafer having a diameter of 5 to 12 inches is manufactured. The silicon wafer is then polished and the front and back surfaces are mirror surfaces. Thereafter, transistors, wirings, and the like are arranged on the silicon wafer.

In the chip manufacturing process, the wafer manufactured in the wafer manufacturing process is diced and separated into chips.
In each of these manufacturing processes, scraps such as cutting scraps, grinding scraps, and polishing scraps are generated when a silicon wafer is cut, ground, polished, and the like. The silicon in the waste is contained in the slice table 1 and the side protector 2. In addition, since the said waste generally contains a liquid component and becomes sludge shape, it is necessary to extract silicon from this sludge-like waste.

  As shown in FIG. 3, the slicing base 5 and the side protector 8 include a molding material manufacturing process (processing S1) for manufacturing a molding material containing silicon contained in scrap generated in the semiconductor manufacturing process, and the molding. A press molding process (process S2) for press molding the molding material manufactured in the material manufacturing process (process S1), a cooling process (process S3) for cooling the molded product, and a heat treatment process (process S4) for heat treating the molded product. It is manufactured through.

(1. Molding material manufacturing process (processing S1))
In the molding material manufacturing process, a molding material to be press-molded is manufactured. This molding material contains silicon contained in scrap generated in the semiconductor manufacturing process and varnish. This molding material manufacturing process includes a varnish manufacturing process (Process S1-1), a primary kneading process (Process S1-2), and a secondary kneading process (Process S1-3).

(1-1 Varnish manufacturing process (Process S1-1))
First, a varnish (binder material) containing a phenol resin is manufactured. A novolac type phenolic resin and methanol are dissolved in a reaction can to obtain a varnish.
In addition, when using a resol type phenol resin, a phenol resin and formaldehyde are made to react with an alkali catalyst, methanol is added after completion | finish of a dehydration reaction, and the varnish of a resol type phenol resin is obtained. Here, the phenol resin in the varnish is preferably 55 parts by mass or more and 65 parts by mass or less, and the methanol is preferably 45 parts by mass or more and 35 parts by mass or less.

(1-2 Primary kneading step (Processing S1-2))
The varnish obtained in the varnish production process, silicon contained in scraps produced in the semiconductor production process, a curing agent, and methanol are mixed and kneaded.
The content of the phenol resin in the kneaded material is preferably 3% by mass or more and 7% by mass or less.
Next, the kneaded material is air-dried and further dried in a 120 ° C. dryer. Then, the volatile component is measured. When the volatile component becomes 1% or more and 1.4% or less, a curing reaction is further performed in a dryer at 160 ° C.
Then, it cools and grind | pulverizes with a grinder. Thereby, a primary kneading material is obtained.

(1-3 secondary kneading process (processing S1-3))
The varnish produced in the varnish production process is added to the primary kneaded material and kneaded. And after air-drying the kneaded material, coarsely pulverized, sieved the pulverized product of 0.6mm diameter or less with a primary sieve,
Thereafter, fine pulverization is performed, and a pulverized product having a diameter of 0.3 mm or less is sieved by a secondary sieve.
Then, this pulverized product is dried so that the volatile component is 2.0% or more and 2.7% or less. Thereby, a molding material will be completed. The content of silicon in the molding material 5 is 50% by mass or more and 70% by mass or less, and the content of the phenol resin is preferably about 30% by mass or more and less than 50% by mass, more preferably , About 35% by mass.
For example, the content of silicon in the molding material is 59% by mass, and the content of phenol resin is 39% by mass.

(2. Press molding process (Process S2))
In the press molding process, the molding material is heated under pressure to perform hot press molding (Process 2).
As shown in FIG. 4, the molding material 5 </ b> A is heated and press-molded by a press molding device 9, and this press molding device 9 includes a mold 90 having a fixed mold 91 and a movable mold 92, and this mold. 90 and a heater 93 arranged around 90. The movable mold 92 and the fixed mold 91 are heated to, for example, 115 ° C. to 120 ° C. by the heater 93, and the molding material 5A is filled in the fixed mold 91. Thereafter, the movable mold 92 is moved to perform mold clamping.
After clamping the mold, the temperature of the heater 93 is gradually increased. When the temperature reaches a certain temperature (for example, about 155 ° C.), the heater 93 is turned off and the mold 90 is lowered to a predetermined temperature (for example, about 120 ° C.). Then, the molded product (slice table 5 or side protector 8) is taken out.

(3. Cooling step (processing S3), heat treatment step (processing S4))
The press-molded molded product (slice table 5 or side protector 8) is taken out from the mold 90, and its periphery is tightened with a cooling air cylinder to perform cooling (processing S3).
Thereafter, the molded product is taken out from the cooling air cylinder, the molded product (slice table 5 or side protector 8) is sandwiched between jigs, the outer peripheral surface is tightened, and heat treatment is performed (processing S4). The heat treatment is preferably performed at 90 ° C. for 4.5 to 5 hours.
When the heat treatment process is finished, the warpage of the molded product (slice table 5, side protector 8) is inspected. If no warp is found, the molded product (slice table 5, side protector 8) is completed.

Therefore, according to this embodiment, the following effects can be produced.
(1) Since the molding material 5A containing silicon contained in scrap generated in the semiconductor manufacturing process and the binder material is hot-press molded into a molded product (slice table 5, side protector 8), it occurs in the semiconductor manufacturing process. Effective use of silicon contained in scrap can be achieved.
In addition, since the silicon content in the molding material 5A is set to 50% by mass or more and 70% by mass or less, silicon can be reliably bonded to each other with a binder material. Thereby, it can prevent that the slice stand 5 and the side protector 8 which are molded articles become weak.

(2) In this embodiment, since the binder material is a varnish containing a phenol resin, the acid resistance and alkali resistance of the slice table 5 and the side protector 8 that are molded products can be improved.
Further, since the phenol resin is dissolved in a volatile solvent to form a varnish, the fluidity is high and kneading can be easily performed when kneading with silicon.
(3) Furthermore, in this embodiment, since the outer peripheral surface of the molded product is tightened and cooled in the cooling step, it is possible to prevent the molded product from being warped during cooling.
(4) In the present embodiment, in the heat treatment step, since the heat treatment is performed by tightening the outer peripheral surfaces of the slice table 5 and the side protector 8 which are molded products, the internal stress of the molded product is released by annealing, The deformation of the molded product can be reliably prevented.

(5) In this embodiment, the slice base 5 is manufactured as a molded product. Since the molded product contains silicon, its hardness is higher than that of a slice table made of conventional carbon, resin alone, glass or the like. The hardness of the slicing table 5 is higher than the hardness of the ingot 3 compared to the conventional slicing table.
When the ingot 3 is installed on the slicing base 5 and the ingot 3 is cut with a multi-wire saw, the wire saw reaches the slicing base 5. When the hardness of the ingot 3 and the slicing base 5 is greatly different, the wire saw may be warped when the wire saw reaches the slicing base 5. This warping of the wire saw may affect the flatness of the wafer.
On the other hand, since the hardness of the slicing base 5 according to the present embodiment is close to the hardness of the ingot 3, warping is unlikely to occur when the wire saw reaches the slicing base 5. Therefore, a wafer with good flatness can be obtained.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the said embodiment, although the slice stand 5 and the side protector 8 were illustrated as a molded article, as a molded article, it is not restricted to this. For example, a tile to be attached to a floor or a wall may be manufactured as a molded product. Since the molded article has good acid resistance and alkali resistance, no problem occurs even if it is used as a tile.
In the above embodiment, the heat treatment is performed by tightening the outer peripheral surface of the molded product, but the present invention is not limited thereto, and the outer peripheral surface of the molded product may not be tightened.

Furthermore, in the said embodiment, although the heat processing process was implemented, the heat processing process does not need to be. By doing in this way, the manufacturing process of a molded article can be simplified.
Moreover, in the said embodiment, although the phenol resin was used as resin which comprises a molding material, not only this but another resin may be sufficient. For example, urea resin, melamine resin, unsaturated polyester resin, acrylic resin, epoxy resin or the like may be used.
And in the said embodiment, although the waste which arose in the semiconductor manufacturing process was knead | mixed with the resin-type binder to the last, and this was grind | pulverized and manufactured the molded article, it is not restricted to this.
That is, for example, a slicing table with a cutting flaw by a multi-wire saw is set in a mold, and further, a scrap containing silicon or the like and a resin binder are kneaded, pulverized, heated and press molded to form a molded product May be obtained.

Next, examples of the present invention will be described.
In the example, according to the diameter of the ingot 3, three types of slice bases 5 having the diameters of the concave portions 11 of 150 mm, 200 mm, and 300 mm were manufactured. The length dimension L and the width dimension W of each slice base 5 are common, L = 450 mm, W = 85 mm, and the height dimension T is T = 8 mm for a 150 mm diameter and T = 5 mm for a 200 mm diameter. The diameter of 300 mm is T = 10 mm.
Moreover, according to the diameter of the ingot 3, the side protector 8 whose diameter is 150 mm, 200 mm, and 300 mm was manufactured. The thickness dimension of each side protector 8 is 5 mm to 20 mm.

(1. Molding material manufacturing process (processing S1))
(1-1 Varnish manufacturing process (Process S1-1))
First, a novolac-type phenol resin and methanol were dissolved in a reaction can to produce a varnish. A novolac-type phenol resin and methanol were dissolved in a reaction can to obtain a varnish. The phenol resin in the varnish was 60 parts by mass, and methanol was 40 parts by mass.

(1-2 Primary kneading step (Processing S1-2))
Next, 10 kg of silicon contained in scrap generated in the semiconductor manufacturing process, 0.783 kg of varnish manufactured in the varnish process, 0.056 kg of hexamethylenetetramine (curing agent), and 3.0 kg of methanol in a kneader, about 10 Kneaded for ~ 30 minutes. Next, the kneaded material was put on a vat and air-dried. Thereafter, the air-dried material was placed in a dryer at 120 ° C. for 5 minutes, and volatile components were measured. After confirming that the volatile components were 1% or more and 1.4% or less, a curing reaction was performed in a dryer at 160 ° C. for about 30 minutes to 45 minutes.
After the curing reaction, the mixture was cooled and pulverized by a power mill pulverizer. As a result, a primary kneaded material was obtained.

(1-3 secondary kneading process (processing S1-3))
10.0 kg of the primary kneaded material and 9.29 kg of the varnish produced in the varnish production process were mixed, kneaded for 10 to 30 minutes, and air-dried on the vat. Then, it is coarsely pulverized in a power mill pulverizer, subjected to primary sieving and sieved to a pulverized product of 0.6 mm or less, further refined by an atomizer, and subjected to secondary sieving to 0.3 mm or less. A pulverized product was obtained.
And what made the volatile component 2.0% or more and 2.7% or less was made into the molding material.
In addition, in order to make a volatile component 2.0% or more and 2.7% or less, the volatile component was adjusted with the dryer of 50 degreeC.

(2. Press molding process (Process S2))
Next, a predetermined amount of the molding material was precisely weighed and subjected to hot press molding in the same manner as in the above embodiment with the temperature change shown in the graph of FIG.
Specifically, the movable mold 92 and the fixed mold 91 are heated to, for example, 115 ° C. to 120 ° C. by the heater 93, and the molding material 5A is filled into the fixed mold 91. Thereafter, the movable mold 91 was moved and the mold was clamped.
After the mold clamping, the temperature of the heater 93 is gradually increased, and the temperature is raised to 160 ° C. during a predetermined time A. The temperature is maintained for C for a certain time in this state, and then 115 to 120 ° C. over a certain time B. Then, the mold 90 was cooled until the molded product (the slicing base 5 and the side protector 8) was taken out.

Times A, B, and C differ depending on the diameter of the ingot 3 and are set as follows.
Time ABC
For 150 mm diameter 18 minutes 8 minutes 30 minutes For 200 mm diameter 30-35 minutes 15 minutes 30 minutes For 300 mm diameter 65-75 minutes 30 minutes 30 minutes Also, the molding pressure in the press molding process is 0.196 N / m ² (200 kgf / cm ² ).

(3. Cooling step (processing S3), heat treatment step (processing S4))
The press-molded molded product (slice table 5, side protector 8) was taken out from the mold 90, and its periphery was fastened with a cooling air cylinder to cool it. The cooling was naturally performed with a flat plate, and the time was about 20 minutes.
Thereafter, the molded product (slice table 5, side protector 8) was taken out from the cooling air cylinder, the molded product (slice table 5, side protector 8) was sandwiched between jigs, the outer peripheral surface was tightened, and heat treatment was performed. The heat treatment was performed at 90 ° C. for 4.5 to 5 hours. Thereafter, warpage of the molded product (slice table 5, side protector 8) was inspected.
As described above, it was possible to obtain a molded product (slice table 5, side protector 8) that reused silicon scraps such as silicon wafer cutting scraps, grinding scraps, and polishing scraps generated in each semiconductor manufacturing process.

  INDUSTRIAL APPLICABILITY The present invention can be used for reusing silicon such as silicon wafer cutting scraps, grinding scraps, and polishing scraps generated in each semiconductor manufacturing process.

The schematic diagram which shows the structure of the multi-wire saw using the molded article which concerns on embodiment of this invention as a jig | tool. It is a perspective view which shows the slice stand and the side protector which are the molded articles concerning embodiment of this invention. It is a flowchart which shows the manufacturing process of the said molded article of this embodiment. It is a schematic diagram which shows the press molding apparatus used in the manufacturing process of the said molded article. It is a figure which shows the relationship between the temperature of the metal mold | die in the press molding process of a molded article, and time.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 3 ... Ingot, 5 ... Slice stand (molded article), 5A ... Molding material, 8 ... Side protector, 9 ... Press molding apparatus, 11 ... Recessed part, 90 ... Mold, 91 ... Fixed mold, 92 ... Movable mold, 93 ... heater

Claims (4)

A method for producing a molded product containing silicon,
A silicon-containing scrap generated in any one of the semiconductor manufacturing processes of silicon ingot cutting, silicon wafer grinding, polishing, and silicon wafer dicing is mixed with a resin-based binder material so that the silicon content is 50. A molding material production process for producing a molding material of mass% or more and 70 mass% or less,
A heating press molding step of molding the molding material manufactured in the molding material manufacturing step under heating and molding a molded product; and
A cooling step of cooling and curing the molded product formed in the heating press step,
The molding material manufacturing process includes:
A primary kneading step of kneading and curing the resin-based binder material and the silicon-containing waste, and then pulverizing to obtain a primary kneaded material;
Kneading the primary mixing materials and the resin-based binder materials, allowed to air dry, and a secondary kneading step to obtain the molding material by crushing,
The said resin-type binder material is a varnish containing the phenol resin obtained by the varnish manufacturing process, The manufacturing method of the molded article characterized by the above-mentioned. In the manufacturing method of the molded article according to claim 1 ,
In previous SL varnish manufacturing step by dissolving the phenolic resin in a volatile solvent, to produce the varnish,
In the primary kneading step, the varnish and the silicon-containing waste are kneaded and cured, and then pulverized to obtain the primary kneaded material,
The kneaded secondary kneaded step and the varnish and the primary mixing materials, allowed to air dry method for producing a molded article, characterized in that to obtain the molding material is pulverized. In the manufacturing method of the molded article according to claim 1 or 2,
In the cooling step, the outer peripheral surface of the molded product is tightened and cooled to cool the molded product. In the manufacturing method of the molded article according to claim 3,
A method for manufacturing a molded product, comprising: a heat treatment step of tightening and heat treating the outer peripheral surface of the molded product cooled in the cooling step.

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