JP3093993B2 - Molding method using wax-like substance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding method using a wax-like substance.

[0002]

2. Description of the Related Art Conventionally, a so-called wax casting method has been used as a method of forming a decorative article having a high-definition pattern or an accessory having a complicated and three-dimensional shape.

[0003] The above-mentioned wax casting method is a method for producing a shaped article using a wax-like substance in the following procedure. That is, first, a woody processing tool or the like such as a chisel, a cutter, a saw, or a file is diverted to process a wax-like substance such as a block into a desired shape. Next, the prototype completed by the above processing is covered with a heat-resistant mold material in which a runner for dewaxing and casting is formed. Next, heat is applied to the mold material from the outside to melt the waxy substance, which is the prototype, and flows out from the runner (dewaxing). Subsequently, the remaining wax-like substance is vaporized, and a desired metal is poured from a runner into a mold (mold) having a hollow inside. Then, the metal is cooled and solidified together with the mold. After that, the mold is broken to take out a molded object made of metal. As a result, a desired model can be manufactured using the wax-like substance.

By the way, various properties (physical properties) of the wax-like substance are closely related to so-called ease of use such as ease of processing and ease of dewaxing of the wax-like substance. When the above-mentioned various properties are slightly changed, the ease of processing the wax-like substance, the ease of dewaxing, and the like greatly change. In other words, when the various physical properties of the wax-like substance deviate from a certain range, that is, an appropriate range where good usability is obtained, when a molded article is manufactured using the wax-like substance, However, the following problems occur.

That is, when the viscosity of the wax-like substance is higher than an appropriate viscosity range, when the wax-like substance is processed to form a prototype, shavings and chips generated by the processing have stickiness. Becomes For this reason, shavings and chips are likely to be clogged with the cutting edge of a chisel or a saw or a file, which is a processing tool. That is, the workability of the wax-like substance decreases.

If the melting point of the wax-like substance is higher than an appropriate temperature range, the wax must be heated to a higher temperature when the wax-like substance (original pattern) is dewaxed from the mold. It will be difficult. Further, since the mold is heated to a high temperature, cracks are easily generated in the mold. When a crack is generated and the mold material is broken, it becomes impossible to manufacture a molded article.

When the hardness of the wax-like substance is smaller than an appropriate hardness range, the original model formed by the processing tends to lose its shape. Also, the surface of the finished prototype cannot be polished. In this case, in order to prevent the model from becoming out of shape, it is necessary to prepare a work environment such as maintaining the temperature of the work place constant.

When the hardness of the wax-like substance is higher than the appropriate hardness range, the viscosity tends to be lower than the appropriate viscosity range. For this reason, the workability of the wax-like substance is reduced.

[0009] As a conventional wax-like substance used in the above wax casting method, for example, beeswax and paraffin wax are known. The above-mentioned paraffin wax is, for example, Nippon Seirosu Co., Ltd. or Ferris
s; United States).

[0010]

However, the physical properties (physical properties) of the above-mentioned conventional wax-like substance (that is, commercially available paraffin wax) have a large rate of change due to a temperature difference. For this reason, the above-mentioned conventional wax-like substance tends to have various physical properties deviating from an appropriate range in which good usability can be obtained, for example, in winter or summer. That is, the above-mentioned conventional wax-like substance has poor so-called ease of use, such as easy processing and dewaxing.

Further, the above-mentioned conventional wax-like substance is deteriorated by repeated heating and cooling, and its physical properties are changed. For this reason, even if the shavings and chips, and the waxy substance recovered by dewaxing are melted and solidified again into a block shape or the like, the physical properties are changed, so that they cannot be reused.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object the ability to be used repeatedly, excellent workability, and easy dewaxing from a mold, that is, so-called good usability. It is an object of the present invention to provide a molding method using a suitable wax-like substance.

[0013]

In order to solve the above-mentioned problems, a molding method using a wax-like substance according to the present invention forms a prototype by processing a wax-like substance, and this prototype is used as a mold. After covering, the prototype is dewaxed, a molten metal is poured into a mold serving as a mold, and a molding method using a wax-like substance to be molded by cooling and solidifying, wherein the wax-like substance is used. , A raw material consisting of a synthetic resin as a raw material and a fuel is put into a combustion basket,
By burning the fuel to melt the synthetic resin, and thermally decomposing a part of the resin to reduce the molecular weight and liquefy it, by dropping a melt of a mixture thereof into an oxygen-deficient catalyst tank, Pyrolyze synthetic resin that has not been thermally decomposed in the melt or synthetic resin that is not sufficiently thermally decomposed,
By burning the combustible high-temperature gas generated by vaporizing a part of the waxy substance in a molten state in the combustion basket while obtaining the waxy substance by depolymerization, the inside of the combustion basket wax-like substance der obtained by a method of controlling the temperature to a predetermined temperature is,
The wax-like substance has a hardness of 40 HDD to 60 HDD,
Indentation capacity until failure is characterized 0.7 mm~0.9 mm der Rukoto. The waxy substance is further number averaged
Molecular weight (Mn) is 3.0 × 10 ³ to 1.0 × 10 ⁴ , weight average molecule
The amount (Mw) is 1.0 × 10 ⁴ to 5.0 × 10 ⁴ , and Mw / Mn is
1.0 ~ 5.0, melting peak temperature 100 ~ 120 ℃, viscosity
However, at 60 ° C, 2.0 × 10 ⁶ poise ~ 8.0 × 10 ⁶ poise, at 80 ° C
2.0 × 10 ⁴ poise to 1.0 × 10 ⁵ poise, 1.0 × 10 ³ po at 100 ° C
ise ~ 7.0 × 10 ³ poise, melting start temperature is 90 ℃ ~ 110 ℃,
Tensile strength of ^{80 kgf / cm 2 ~100kgf / cm} 2, bending strength, 0.6K
^{gf / mm 2 ~0.9kgf / mm 2} , a flexural modulus of 40 kgf / mm ² ~60 kgf
/ mm ² . Synthetic tree that is the above raw material
Fat is a non-crosslinked, low-crosslinked, or highly crosslinked polyethylene resin
Polyolefins and polystyrenes such as fats and polypropylene resins
It is preferably a ren resin.

The physical properties of the above-mentioned wax-like substance, for example, various physical properties such as melting point, viscosity, hardness, etc., are within an appropriate range in which the workability is excellent and dewaxing from a mold material as a mold is easy. Because it fits, it can be easily processed and does not easily soften or collapse. According to the above method, it is possible to use repeatedly, it is excellent in processability, and it is easy to dewax from the mold material, that is, a desired shaped article using a so-called easy-to-use waxy substance, for example, high-definition A decorative article having a pattern, an accessory having a complicated and three-dimensional shape, an art and craft, and the like can be suitably manufactured. Further, only one model can be manufactured from one prototype. For this reason, the manufactured shaped article has a high scarcity value.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

The wax-like substance according to the present embodiment is:
For example, it can be obtained by subjecting a synthetic resin as a raw material that is heated and melted to a thermal decomposition reaction. Examples of the synthetic resin include non-crosslinked, low-crosslinked, or highly crosslinked polyolefins such as polyethylene resins and polypropylene resins, and polystyrene resins. The synthetic resin is not particularly limited as long as it is a resin capable of obtaining a wax-like substance by a thermal decomposition reaction. For example, waxy substances can be produced at low cost from synthetic resin waste such as polyethylene resin and polypropylene resin. The method for producing the wax-like substance will be described later in detail.

Next, the wax-like substance according to the present embodiment will be described below while appropriately comparing it with a conventional wax-like substance.

First, various physical properties of the wax-like substance will be described. Elemental analysis of the wax-like substance was performed by the following method. The molecular weight and molecular weight distribution of the waxy substance were measured by the following methods. Further, various physical properties (physical properties) of the waxy substance were measured. That is, the melting point and specific gravity of the wax-like substance were measured by the following methods, and a flow test, a hardness test, a tensile test, and a bending test were performed by the following methods. Then, the wax-like substance and the conventional wax-like substance, a wax manufactured by Nippon Seiro Wax Co., Ltd. (hereinafter, referred to as a conventional product A) and a wax manufactured by Ferris (U.S.A.) (hereinafter, referred to as a conventional product B). Were measured together with various physical properties of the conventional product A and the conventional product B. Table 1 summarizes the obtained results.

[Elemental Analysis] Each weight% (wt%) of carbon, hydrogen, nitrogen and sulfur and each content (μg / g) of total chromium, cadmium and lead were measured. Each weight% of carbon, hydrogen and nitrogen was measured by a C, H and N meter. The weight percentage of sulfur was measured by a turbidimetric method after burning by a combustion tube type quartz tube oxygen method based on JIS K2541. Each content of total chromium, cadmium and lead was measured by the atomic absorption method. Each measurement was performed under the conditions of a test room temperature of 19 ° C.

[Molecular Weight and Molecular Weight Distribution] The number average molecular weight (Mn) and the weight average molecular weight (Mw) were measured by GPC. Measurement conditions were as follows: Column: AD80M / S Mobile phase: o-dichlorobenzene Detector: IR (3.42 μm) Temperature: 140 ° C Flow rate: 1.0 ml / min. Sample concentration: 2.0 mg / ml The test was performed at room temperature of 22 ° C.

[Melting point] Based on JIS K 7122,
The melting peak temperature (° C.) was measured by the DSC method. The tester is DSS-220C manufactured by Seiko Electronic Industry Co., Ltd.
It was used. The measurement conditions were as follows: heating rate: 10 ° C./min. The measurement was performed at a test room temperature of 21 ° C.

[Specific gravity] Based on JIS K 7112,
It was measured by the underwater displacement method. The measurement was performed at the test room temperature 21
The test was performed under the condition of ° C.

[Flow test] Based on JIS K 7210, the viscosity (poise) was measured using a Koka type flow tester.
And the melting start temperature (° C.) were measured. The viscosity is 40 ℃,
The values at 60 ° C, 80 ° C, and 100 ° C were measured by a constant temperature test. The measurement conditions were as follows: Die diameter: 1 mm Test load: 10 kgf to 500 kgf The melting start temperature was measured by a temperature rise test. The measurement conditions were as follows: die diameter: 1 mm, test load: 10 kgf, heating rate: 3 ° C./min.

[Hardness test] Hardness (HDD) was measured based on JIS K 7215. The measurement was performed under the conditions of a test room temperature of 21 ° C.

[Tensile test] Tensile strength (kgf / cm ² ) was measured based on JIS K 7113. The measurement conditions were as follows: Test piece: Type 1 Test speed: 50 mm / min. The measurement was performed at a test room temperature of 21 ° C.

[Bending Test] Based on JIS K 7203, bending strength (kgf / mm ² ), bending elastic modulus (kgf / mm ² )
The pushing amount (mm) before breaking and the pushing amount (mm) until yielding were measured. The measurement conditions were as follows: Test piece: 80 mm × 10 mm × 2 (t) mm Test speed: 1 mm / min. Distance between fulcrums: 30 mm The measurement was performed at a test room temperature of 21 ° C.

[0027]

[Table 1]

The results of the above measurements will be discussed below. That is, the physical properties and the like of the wax-like substance of the present embodiment are compared with those of the conventional wax-like substances of the conventional product A and the conventional product B, and the respective physical properties and the like are compared. Consider the differences.

First, the analysis results of elemental analysis will be considered. The molecular formula of the saturated chain hydrocarbon (paraffin hydrocarbon) is represented by C _n H _{2n + 2} . The atomic weight of carbon is 12.011,
Since the atomic weight of hydrogen is 1.00794, the weight ratio of carbon to hydrogen (C / H) is approximately 5.958.

The weight ratio of the waxy substance is 5.909.
Also, the total weight percent of carbon and hydrogen is 98.8%.
That is, it is understood that the main component of the wax-like substance is composed of a saturated chain hydrocarbon.

On the other hand, the weight ratio of the conventional product B was 6.252.
It is. A large weight ratio indicates that the weight of hydrogen is smaller than the weight of carbon. Also, the total weight percent of carbon and hydrogen is 97.9%. That is, the conventional product B
Is thought to contain, as impurities, a chain hydrocarbon having a substituent containing oxygen, such as a carbonyl group, a carboxyl group, or a hydroxyl group, in addition to the saturated chain hydrocarbon. Also, from the magnitude of the weight ratio, it is possible that unsaturated hydrocarbons may be mixed.

Next, the measurement results of the molecular weight and the molecular weight distribution will be considered. The waxy substance has a number average molecular weight (M
n) is 6.1 × 10 ³ , and the weight average molecular weight (Mw) is 2.8 × 10 3
⁴ , Mw / Mn is 4.5. Although not shown, the peak of the molecular weight distribution curve is slightly biased toward the lower molecular weight side. On the other hand, the conventional product A has Mn of 1.9 × 10 ³ and M
w is 2.1 × 10 ³ . That is, it is understood that the conventional product A has a clearly smaller molecular weight than the wax-like substance. Conventional product B has Mn of 8.0 × 10 ³ and Mw of 4.7 × 10 ³ .
× 10 ⁴ and has a molecular weight almost equal to the molecular weight of the wax-like substance. However, since Mw / Mn is 5.9, the width of the molecular weight distribution is slightly wider than that of the wax-like substance. I understand.

The waxy substance (or the conventional product A or the conventional product B) has different physical properties if the composition, molecular weight and molecular weight distribution are different. In addition, the wax-like substance is a mixture of various kinds of saturated chain hydrocarbons, and its various physical properties appear as an integrated result of a complex crystal structure of the component hydrocarbon.
Therefore, it is considered that the difference between the physical properties of the wax-like substance and the physical properties of the conventional products A and B is due to slight differences in the composition, molecular weight, and molecular weight distribution.

Next, the results of measuring the melting point will be considered. The waxy material has a peak melting temperature of 109 ° C. On the other hand, the conventional product A has a melting peak temperature of 50 ° C. because of its small molecular weight. In other words, it can be seen that the conventional product A tends to lose its original shape by processing when the temperature or room temperature is high, for example, in the summer. Therefore, the conventional product A
When a prototype is created using a computer, it is necessary to prepare a working environment such as keeping the temperature of the work place constant.

The waxy substance was odorless in a molten state. On the other hand, the conventional product B produced an unpleasant smell when melted. From this, the conventional product B
It can be seen that contains the above impurities in addition to the saturated chain hydrocarbon.

Next, the test results of the flow test will be considered. The waxy substance has a viscosity of 4.3 × 10 ⁶ poise at 60 ° C., 8
Melting start temperature is 97 ° C with 5.3 × 10 ⁴ poise at 0 ° C. and 3.5 × 10 ³ poise at 100 ° C. (The viscosity at 40 ° C. was not measurable because the wax-like substance did not melt at all).

On the other hand, the conventional product A has a viscosity of 4.2 × 10 ⁵ poise at 40 ° C. and 9
3. 7.2 at 80 ° C., melting start temperature is 46 ° C. (Viscosity at 100 ° C. could not be measured by the above-mentioned measuring method because Conventional A was completely melted). That is, it is understood that the conventional product A easily loses its shape as a prototype as described above. Conventional product B has a viscosity
3.4 × 10 ⁶ poise at 60 ° C, 2.2 × 10 ⁵ poise at 80 ° C, 100 ° C
5.4 × 10 ³ poise and a melting start temperature of 98 ° C. (the viscosity at 40 ° C. could not be measured because the conventional product B did not melt at all).

Usually, when a wax-like substance (or conventional product A or conventional product B) is processed using a processing tool such as a chisel, a cutter, a saw, a file, or the like, contact of the wax-like substance with the processing tool is made. The part is heated by frictional heat.
For this reason, for example, when the viscosity around 80 ° C. is high, when processing a wax-like substance to form a prototype, shavings and chips generated by the processing are heated by frictional heat and have stickiness, and the processing tool Cling to In other words, the blade of the chisel,
Alternatively, shavings and chips are easily clogged with the eyes of a saw or a file, and the workability of the wax-like substance is reduced. The viscosity at 80 ° C. is 5.3 × 10 ⁴ poise for the waxy substance and 2.2 × 10 ⁵ poise for the conventional product B. This indicates that the wax-like substance is easier to process than the conventional product B. The reason why the viscosity of the wax-like substance at 80 ° C. is lower than that of the conventional product B seems to be due to the fact that the peak of the molecular weight distribution curve of the wax-like substance is slightly biased toward the low molecular weight side.

The viscosity at 100 ° C. of the waxy substance is lower than that of the conventional product B. In other words, at 100 ° C,
The wax-like substance flows more easily than the conventional product B. For this reason, it can be seen that the wax-like substance is easier to dewax from the mold, which is the mold, than the conventional product B.

Next, the test results of the hardness test will be considered. The wax-like substance has a hardness of 51 HDD. On the other hand, the conventional product B has a hardness of 48 HDD. From this, it can be seen that the prototype of the wax-like substance is less likely to lose its shape than the conventional product B.

Next, the test results of the tensile test will be considered. The waxy substance has a tensile strength of 92 kgf / cm ² .
On the other hand, the conventional product B has a tensile strength of 79 kgf / cm ² .

When a wax-like substance (or a conventional product A or a conventional product B) is processed to form a prototype, if the tensile strength is low, for example, minute cracks are generated and the processed portion is not finished finely. . That is, the prototype does not have the desired cleanliness. The tensile strength of the wax-like substance is higher than that of the conventional product B. From this, it is understood that the waxy substance can form a more beautiful prototype than the conventional product B.

Next, the test results of the bending test will be considered. The wax-like substance has a flexural strength of 0.74 kgf / mm ² and a flexural modulus of 52 kgf / mm ² . In contrast, conventional product B
Has a flexural strength of 1.03 kgf / mm ² and a flexural modulus of 31 kgf / mm ²
It is. In addition, the amount of wax-like substance
It was 0.82 mm (the indentation amount before yielding could not be measured because the test piece was destroyed at 0.82 mm). On the other hand, the conventional product B had an indentation amount up to yield of 5.12 mm (the indentation amount up to breaking was not measurable because the test piece was not broken).

When processing a wax-like substance (or conventional product A or conventional product B) to form a prototype, if the bending strength is large, for example, when the chip is separated from the wax-like substance body, The processed part cannot be finished finely because the connection part between the resin and the wax-like substance main body is extended. Also, if the flexural modulus is small, for example, when a wax-like substance is cut with a chisel or a cutter, the chips are finely broken near the cutting edge of the chisel or the cutter, and the processed portion is not finished finely. That is, the prototype does not have the desired cleanliness. The bending strength of the wax-like substance is smaller than that of the conventional product B. Further, the bending elastic modulus of the wax-like substance is larger than that of the conventional product B. As is clear from the results in Table 1,
Since the wax-like substance has higher hardness and flexural modulus than the conventional product A and the conventional product B, it can be seen that the wax-like substance is easy to cut and work. From this, it can be seen that the waxy substance can form a more beautiful prototype as compared with the conventional product B.

A prototype was prepared using the wax-like substance, the conventional product A and the conventional product B, and the difference in workability at this time was determined.
In other words, usability was compared. As a result, processing such as engraving could be easily applied to the waxy substance. On the other hand, in the conventional product B, since shavings adhere to the chisel, it takes time and effort to perform processing such as engraving. Also, the prototype made by processing waxy substances,
Did not lose shape. On the other hand, the prototype created by processing the conventional product A collapsed. In addition, the wax-like substance was harder than the conventional product B but was not brittle, and did not cause any inconvenience when performing the above processing.

As is apparent from the above results, the wax-like substance does not easily soften or lose its shape during and after working such as engraving. For this reason, a waxy substance having a block shape or the like can be easily engraved by a layman using a woodworking tool such as a chisel. Since the wax-like substance is easy to handle even by amateurs, it can be suitably used, for example, for casting, engraving, etc., that is, for manufacturing a molded article (that is, a molding method).

It is considered that the difference in usability between the wax-like substance and the conventional products A and B is caused by the slight differences in the above-mentioned various physical properties. That is, the difference in usability is presumed to be mainly due to the difference in the weight ratio between carbon and hydrogen, the total weight% of carbon and hydrogen, the molecular weight, and the molecular weight distribution.

Therefore, the inventor of the present application has intensively studied the range of physical properties of the wax-like substance which can provide good usability. As a result, it is not clear which of the above physical properties is significantly related to the ease of processing when creating a prototype from a waxy substance, but if each physical property is within the range shown below, It was found that the workability of the wax-like substance was good.

That is, the weight ratio of carbon to hydrogen (C / H)
Is preferably 5.839 to 6.018. The total weight percent of carbon and hydrogen is preferably from 98.5% to 100%. The number average molecular weight (Mn) is preferably 3.0 × 10 ³ to 1.0 × 10 ⁴ , the weight average molecular weight (Mw) is preferably 1.0 × 10 ⁴ to 5.0 × 10 ⁴ , and Mw / Mn is preferably 1.0 to 5.0. . The melting peak temperature is preferably from 100 ° C to 120 ° C. Viscosity at 60 ° C
2.0 × 10 ⁶ poise ~ 8.0 × 10 ⁶ poise, 2.0 × 10 ⁴ poi at 80 ℃
se ~ 1.0 × 10 ⁵ poise, 1.0 × 10 ³ poise ~ 7.0 × 1 at 100 ℃
0 ³ poise is preferable, and the melting start temperature is preferably 90 ° C to 110 ° C. The hardness is preferably from 40 HDD to 60 HDD. Tensile strength is preferably ^{80 kgf / cm 2 ~100kgf / cm} 2. Flexural strength is preferably ^{0.6kgf / mm 2 ~0.9kgf / mm 2} , the flexural modulus is preferably ^{40 kgf / mm 2 ~60 kgf /} mm 2. The pushing amount until breaking is preferably 0.7 mm to 0.9 mm. If the respective physical properties are out of the above ranges, the workability of the wax-like substance becomes poor.

As described above, the wax-like substance according to the present embodiment has a main component of a saturated chain hydrocarbon, a weight ratio of carbon to hydrogen (C / H) of about 5.958, and carbon and hydrogen. The total weight percent of hydrogen is 98.8%. For this reason, even if heating and cooling at a low temperature of, for example, 120 ° C. or less are repeated, the wax-like substance is not deteriorated and has excellent stability. The waxy substance has a number average molecular weight (Mn) of 6.1 ×
It is 10 ³ , the weight average molecular weight (Mw) is 2.8 × 10 ⁴ , and Mw / Mn is 4.5. For this reason, the physical properties of the wax-like substance, for example, various physical properties such as melting point, viscosity, and hardness, are within an appropriate range in which the workability is excellent and the dewaxing from the mold as a mold is easy. That is, the waxy substance can be easily processed, and does not easily soften or lose its shape.

As a result, a wax-like substance which can be used repeatedly, has excellent workability, and is easily dewaxed from a mold material, that is, a so-called easy-to-use wax-like substance is obtained.

The procedure for forming a shaped article using the wax-like substance (so-called wax casting method) will be described below with reference to FIG.

First, a wax-like substance such as a block shape having a size corresponding to the size of a model to be manufactured is diverted by using, for example, a woodworking tool such as a chisel, a cutter, a saw, and a file. Processing is performed to obtain a desired shape, that is, a shape of a modeled object. At this time, after drafting the molded article on the waxy substance, the waxy substance may be processed, or the waxy substance may be processed immediately without drafting.
In addition, the surface of the wax-like substance may be polished using a paper file, cloth, or the like, if necessary. If the surface of the wax-like substance is polished, the surface of the molded article is finished smoothly. Accordingly, the time required for polishing the shaped object made of metal is reduced, and the labor is also reduced.

Since the prototype made from the wax-like substance does not collapse, it is not necessary to prepare a working environment (for example, to keep the temperature of the working place constant). Therefore, the working place when processing the wax-like substance is not particularly limited. Further, the shape of the wax-like substance before processing is not limited to the above-described block shape. For example, when the shaped object to be manufactured is, for example, tableware such as a dish or a cup, the wax-like substance may have a shape close to the shape of the dish or the cup.

Next, as shown in FIG. 1 (a), after a casting opening (not shown) is attached to an appropriate position of the prototype 10 completed by the above processing, the prototype 10 is made of a heat-resistant material such as gypsum. Cover with slurry. Thereafter, the gypsum is hardened and the casting hole is removed. That is, the prototype 10 is covered with the heat-resistant mold 11. A runner 11a for dewaxing and casting is formed in the mold material 11 at the position where the casting port was attached.

Next, as shown in FIG. 5B, heat is applied to the mold 11 from the outside to melt the wax-like substance, which is the prototype 10, and the molten wax-like substance 10 'flows from the runner 11a. Get out (dewax). Note that, when heating the mold member 11, for example, an autoclave or the like may be used. A heating temperature of 120 ° C. or less is sufficient. For this reason, there is no possibility that cracks will occur in the shape member 11 during the dewaxing operation, and the above dewaxing operation is facilitated.

Thereafter, the mold material 11 is fired using, for example, an electric furnace or a gas furnace, and the molten wax-like substance 10 ′ remaining in the mold material 11 is completely vaporized. As a result, the interior of the mold 11 becomes hollow. Next, the mold material 11 that became the mold
Is gradually cooled to a mold temperature suitable for casting.

Subsequently, as shown in FIG. 3C, a molten metal 12 'to be a molded object 12 (FIG. 3D) is poured into a runner 11a.
From the mold 11. As the metal, for example, desired metals such as platinum, gold, silver, copper, aluminum, and alloys thereof, and stainless steel can be used, but are not particularly limited. Examples of the casting method include, but are not particularly limited to, a centrifugal casting method, a reduced pressure casting method, a pressure casting method, and a vacuum casting method. After that, the molten metal 12 ′ is
Cool together with 1 to solidify.

Next, as shown in FIG. 5D, the molded material 12 is taken out by destroying the shape member 11 with, for example, a hammer or a mallet. In addition, the run 12a of the mold 11 is
The burr portion 12a may be formed at the position where the is formed. In this case, the burr portion 12a made of surplus metal may be scraped off using a file or the like.

As described above, in the molding method using the wax-like substance according to the present embodiment, the main component is a saturated chain hydrocarbon, and the weight ratio (C / H) of carbon to hydrogen is 5.8.
39 to 6.018, and the total weight percent of carbon and hydrogen is 9
8.5% to 100% with a number average molecular weight (Mn) of 3.0 × 1
0 ³ to 1.0 × 10 ⁴ and a weight average molecular weight (Mw) of 1.0
× 10 ⁴ to 5.0 × 10 ⁴ and Mw / Mn is 1.0 to 5.0
A prototype 10 is prepared by processing a wax-like substance, and the prototype 10 is covered with a mold 11. Then, the prototype 10 is dewaxed, and a molten metal 12 ′ is poured into the mold 11 serving as a mold and cooled. This is a method of forming the shaped object 12 by solidification.

The physical properties of the above-mentioned wax-like substance, for example, various physical properties such as melting point, viscosity, hardness, etc., are in an appropriate range in which the workability is excellent and the dewaxing from the mold material 11 is easy. , It can be easily processed and does not easily soften or lose its shape.

[0062] Thus, it is possible to suitably manufacture a desired shaped article, for example, a decorative article having a high-definition pattern, an accessory having a complicated and three-dimensional shape, an art and craft using the wax-like substance. it can. Specific examples of the object are figurines, nameplates, dishes, seals, brooches, rings,
Examples include, but are not limited to, pendants, key chains, accessory cases, Buddha statues, and the like. Further, only one model can be manufactured from one prototype. Therefore, the shaped object to be manufactured has a rare value. In addition, since the prototype 10 does not lose its shape, the prototype 10 itself can be used as a decoration or the like in some cases.

The wax-like substance according to the present embodiment is:
As described above, the wax-like substance is preferably used in a so-called wax casting method, but the wax-like substance can also be used in a so-called lost wax manufacturing method. In this case, by molding the prototype 10 with, for example, silicone rubber or the like, it is possible to mass-produce a molded article having the same shape using the rubber mold.

The physical properties of the wax-like substance do not change even when heating and cooling at a low temperature of, for example, 120 ° C. or less are repeated. For this reason, shavings and chips generated when creating a prototype, or dewaxed wax-like substances,
After being collected and melted, it can be reused any number of times by pouring it into a box and solidifying it again into a block shape or the like of a desired size. Therefore, it is economical. Then, even when the processing of the wax-like substance has failed, it can be returned to the original block shape or the like by being melted and then poured into a box and solidified. Therefore,
In a shaping method using a wax-like substance, the wax-like substance can be processed again and again until a desired prototype is completed.

For example, when the shaped object to be manufactured is tableware such as a dish or a cup, the wax-like substance is solidified by using a box having a shape close to the shape of the dish or the cup. Good. Thereby, the wax-like substance can be formed into a shape close to the shape of a dish or a cup, so that the processing time can be reduced.

The box-shaped material is not particularly limited as long as it has a heat-resistant temperature higher than the melting temperature of the wax-like substance. Since the wax-like substance does not adhere to the box, the mold release from the box is good.
In addition, the above-mentioned conventional product B easily adheres to a box shape, and therefore,
The mold release from the box type is poor.

Next, a method for producing a wax-like substance will be described below with reference to an example.

As shown in FIG. 2, the wax-like substance producing apparatus includes a storage tank 1 for storing the wax-like substance C.
It has. The storage tank 1 is supported by legs 1a. A cylindrical combustion basket 2 is integrally mounted and fixed to the tank upper end opening 1b of the storage tank 1. On the side wall of the combustion basket 2, countless air introduction holes 2b are formed. The upper end opening 2c of the combustion basket 2 is in an open state. In the lower part of the combustion basket 2,
Rostor 3, which is a convex material receiving tray, is installed so as to cover lower end opening 2a of combustion basket 2 from above. A number of rostr holes 3a are formed in the rostr 3. Then, the raw material A (to be described later) is placed on the roaster 3.

A closed box-shaped catalyst tank 4 is attached to the lower part of the combustion basket 2 so as to close the lower end opening 2a from below. The catalyst tank 4
The entire wall has a mesh portion 4a. The above-mentioned catalyst tank 4
The inside is filled with a catalyst for promoting a thermal decomposition reaction of the melt B (described later), for example, a linear catalyst 4b made of a metal such as platinum or copper. Then, the melt B passes between the linear catalysts 4b.

A cylindrical air balancer 5 is provided on the outer periphery of the combustion basket 2 for adjusting the amount of air to be supplied to the combustion basket 2. The air balancer 5 is installed at a predetermined distance from the combustion basket 2. In addition, an opening 5a for introducing air is provided below the air balancer 5. The upper part of the air balancer 5 is open.

A plurality of communication pipes (not shown) are provided between the storage tank 1 and the combustion basket 2. These communication pipes are connected to a pump (not shown) for sending out gas generated in the storage tank 1 to the combustion basket 2.

A pipe-shaped heater 6 is provided on the inner bottom 1c of the storage tank 1 in order to raise the temperature of the molten wax-like substance C. The heater 6 heats the wax-like substance C by electric heating or high-frequency heating. Further, a temperature sensor 7 such as a bimetal or a thermocouple for detecting the temperature of the wax-like substance C is provided inside the storage tank 1. The heater 6 includes a control unit 8
Controls ON / OFF control or proportional control. The control means 8 controls the heater 6 based on the signal from the temperature sensor 7 so as to keep the wax-like substance C at a predetermined temperature.

Next, a method for producing the wax-like substance C using the production apparatus having the above configuration will be described.

First, a predetermined amount of a raw material A composed of a synthetic resin as a raw material and a fuel as a highly crosslinked polyethylene resin or a polypropylene resin is charged into the combustion basket 2. Next, the synthetic resin is melted by igniting and burning the fuel, and a part of the synthetic resin is thermally decomposed to be reduced in molecular weight and liquefied. Then, a melt B, which is a mixture thereof, is dropped from the roastor holes 3a, passes between the linear catalysts 4b of the catalyst tank 4, and is dropped into the storage tank 1.

At this time, oxygen in the catalyst tank 4 and the storage tank 1 reacts with the melt B and is quickly consumed. Therefore, the inside of the catalyst tank 4 and the inside of the storage tank 1 are in an oxygen-deficient state. Thereby, the resin which has not been thermally decomposed or the resin which has not been thermally decomposed in the melt B is thermally decomposed mainly in the catalyst tank 4 in an oxygen-deficient state, and becomes a low molecular weight wax substance C. The wax-like substance C is stored in the storage tank 1 in a molten state.

The waxy substance C in a molten state
Is heated by the heater 6 and controlled by the temperature sensor 7 and the control means 8, so that its melting temperature is maintained at a predetermined temperature. Therefore, since the wax-like substance C is in an oxygen-deficient state and has a stable melting temperature, the high-heat gas G such as a flammable ethylene gas in which a part of the wax-like substance C is vaporized is used. It occurs stably. The melting temperature of the waxy substance C is about 600
It should just be set so that it may be set to ° C.

The hot gas G whose generation amount is controlled as described above
Reaches the combustion basket 2 where the raw material A is burned, by ascending through the catalyst tank 4 and the rostral 3 or via a communication pipe and a pump (not shown). The high-heat gas G is mixed with air introduced from the air introduction holes 2b and burns. For this reason, the temperature in the combustion basket 2 is controlled to a predetermined temperature.
Thereby, the melting / decomposition of the raw material A continuously supplied to the combustion basket 2 is continued. The internal temperature of the combustion basket 2 is preferably about 1100 ° C.
The particulate carbon is also generated from the wax-like substance C together with the high-temperature gas G, and the generated particulate carbon is entirely burned in the combustion basket 2. Therefore, carbon soot does not adhere to the inside of the combustion basket 2. Therefore, carbon soot is not mixed into the wax-like substance C.

By the above method, the wax-like substance according to the present embodiment is manufactured. Of course, the production apparatus and the production method of the wax-like substance are not limited to the production apparatus and the production method described above. That is, the wax-like substance according to the present embodiment is not limited to those manufactured by the above-described method. In other words, as described above, the wax-like substance can be used repeatedly, is excellent in workability, and is easily dewaxed from the mold material, that is, if it has the function and effect of so-called good usability. , May be manufactured in any manner.

[0079]

According to the molding method using a wax-like substance according to the present invention, as described above, a prototype is prepared by processing a wax-like substance, and after covering this prototype with a mold, the above-mentioned prototype is removed. Waxing, a molding method using a wax-like substance to cast a molten metal into a mold material that has become a mold, and cooling and solidifying the molded article, wherein the wax-like substance is:
A raw material consisting of a synthetic resin as a raw material and a fuel is put into a combustion basket, and the synthetic resin is melted by burning the fuel, and a part of the synthetic resin is thermally decomposed into a low-molecular-weight liquid. By dropping the melt, which is a mixture of them, into a catalyst tank in an oxygen-deficient state, the synthetic resin that has not been thermally decomposed or the synthetic resin that is not sufficiently decomposed in the melt is thermally decomposed to lower the molecular weight and wax. By burning the combustible high-temperature gas generated by the vaporization of a part of the waxy substance in a molten state in the combustion basket, the temperature in the combustion basket is maintained at a predetermined temperature. Ri waxy substance der obtained by a method of controlling, the wax-like substance, the hardness, 40
HDD ~ 60 HDD, pushing amount until breaking, 0.7 mm ~ 0.9
a mm der Ru way. In the above method, the wacks
The slab-like substance further has a number average molecular weight (Mn) of 3.0 × 10
³ to 1.0 × 10 ⁴ , weight average molecular weight (Mw) 1.0 × 10 ⁴
5.0 × 10 ⁴ , Mw / Mn 1.0-5.0, melting peak temperature
Degree of 100 ℃ ~ 120 ℃, viscosity at 60 ℃ 2.0 × 10 ⁶ poise ~
8.0 × 10 ⁶ poise, 2.0 × 10 ⁴ poise ~ 1.0 × 10 ⁵ poi at 80 ℃
se, 1.0 × 10 ³ poise to 7.0 × 10 ³ poise at 100 ° C , melt open
Starting temperature of 90 ° C. to 110 ° C., a tensile strength of 80 kgf / cm ² ~100kgf
/ cm ² , bending strength is 0.6kgf / mm ^{2 to} 0.9kgf / mm ² , bending elasticity
Preferably, the rate is between 40 kgf / mm ^{2 and} 60 kgf / mm ² . Up
The synthetic resin as the raw material is non-crosslinked, low-crosslinked, or
Highly crosslinked polyethylene resin, polypropylene resin, etc.
Preferably a polyolefin or polystyrene resin
No.

The physical properties of the wax-like substance, for example, various properties such as melting point, viscosity, hardness, etc., are in an appropriate range that is excellent in workability and easy to dewax from a mold material as a mold. Because it fits, it can be easily processed and does not easily soften or collapse. Thereby, a desired shaped article using a wax-like substance, for example,
The present invention has an effect that a decorative article having a high-definition pattern, an accessory having a complicated and three-dimensional shape, an art and craft, and the like can be suitably manufactured. Further, only one model can be manufactured from one prototype. For this reason, the manufactured molded article also has the effect of increasing the scarcity value.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a procedure of a molding method using a wax-like substance according to an embodiment of the present invention;
(A) is a step of covering the mold with a mold, (b) is a step of melting the mold and dewaxing from the mold, (c) is a step of pouring a molten metal into the mold, and (d) is a mold. Respectively, and the steps of taking out the modeled object by destroying are shown.

FIG. 2 is a schematic cross-sectional view showing one example of an apparatus for producing the wax-like substance.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Prototype 11 Model material 11a Runner 12 Modeled object 12 'Molten metal

Claims (3)

(57) [Claims] (1) processing a wax-like substance to form a prototype;
After covering the prototype with a mold, the above-described mold is dewaxed, a molten metal is poured into the mold that has become a mold, and a molding method using a wax-like substance to be molded by cooling and solidifying, The wax-like substance is to put a raw material composed of a synthetic resin, which is a raw material, and a fuel into a combustion basket and burn the fuel to melt the synthetic resin and thermally decompose a part thereof. Liquefaction and liquefaction, and by dropping a mixture of these melts into a catalyst tank in an oxygen-deficient state, thermally decomposes synthetic resin that has not been thermally decomposed or that has insufficient thermal decomposition. Then, while a low-molecular-weight wax-like substance is obtained, a part of the wax-like substance in a molten state is vaporized, and the combustible high-temperature gas generated is burned in the above-described combustion basket, so that the combustion is performed. Ri waxy substance der obtained by a method of controlling the temperature of use in the basket at a predetermined temperature, the wax-like substance, the hardness, 40HDD～60HDD,
Indentation capacity until failure, molding method using a wax-like substance, wherein 0.7 mm~0.9 mm der Rukoto. 2. The wax-like substance has a number average molecular weight (M
n) is 3.0 × 10 ³ to 1.0 × 10 ⁴ , and the weight average molecular weight (M
w) is 1.0 × 10 ⁴ to 5.0 × 10 ⁴ , and Mw / Mn is 1.0 to 5 .
0, melting peak temperature is 100 ℃ ~ 120 ℃, viscosity is 60 ℃
2.0 × 10 ⁶ poise ~ 8.0 × 10 ⁶ poise, 2.0 × 10 ⁴ poi at 80 ℃
se ~ 1.0 × 10 ⁵ poise, 1.0 × 10 ³ poise ~ 7.0 × at 100 ℃
10 ³ poise, melting start temperature is 90 ℃ ~ 110 ℃, tensile strength is 80
kgf / cm ² 〜100kgf / cm ² , Flexural strength 0.6kgf / mm ² 〜0.9k
gf / mm ^2, Dearuko flexural modulus ^{40 kgf / mm 2 ~60 kgf /} mm 2
The wax-like substance according to claim 1, wherein the wax-like substance is used.
Modeling method. 3. The synthetic resin as the raw material is non-crosslinked or non-crosslinked.
Low or high cross-linked polyethylene resin, polypropylene
Polyolefin or polystyrene resin such as ren resin
The wax-like material according to claim 1 or 2, wherein
A molding method using quality.