JPS6183666A - Carbon fiber reinforced gypsum model and original mold and intermediate mold for molded mold, gypsum powder and manufacture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention eliminates internal stress caused by external mechanical forces and temperature differences by uniformly dispersing carbon fibers of a predetermined length in a monofilament state at a predetermined ratio in plaster, which is a base material. Carbon 1214-reinforced gypsum models and moldings that increase the mechanical strength of the material, reduce the volumetric expansion of gypsum during curing and drying after curing, and reduce the coefficient of thermal expansion of molded products. The present invention relates to part prototypes, intermediate molds thereof, gypsum powder thereof, and methods for manufacturing the same.

In this specification, the term "gypsum model" refers to a sample shape of a three-dimensional object or a shape at its latitude.

Therefore, it is also a model or model made using plaster to have the same shape as a part or the whole of the intended final product, and in terms of form, it is itself a Q-end object. . Therefore, in the case of a model such as Gold 4, the side wall itself may be a holly product, which is the target. In addition, "plaster molded original material" refers to a plaster nest mold that serves as the basis for reproduction when a mold for mass production is completed through several casting reproduction processes. In other words, the "original mold" refers to the mold in the starting tin for molding the mold, and refers to the mold that is the actual starting point of the molding operation. Although it is not the final object itself, if expansion and contraction from the original to the final product is not a problem, and if the shape is similar to the final product, it may not be distinguishable from the model. In that case, the final product is 1
When producing small quantities of one or more products, the product is treated as a copy of a model, and is not considered a prototype, no matter how close it is to the starting line. Furthermore, the term "gypsum intermediate mold" refers to all molds that are formed between the two molds when a mold is reproduced from the original mold by a casting process. For example, in the case of molding the R porcelain Sei 7I45 type, the t! A master mold that is cast in the middle of two molds,
There are two types of plaster molds called case molds.

Conventionally, there have been various methods to increase the strength of a two-stone plaster model or an intermediate model thereof. There are methods to reduce the amount of water mixed in, or to mix cement F or resin into the plaster, and there is also a method to mix natural materials such as hemp or glass fiber into the plaster.

When cement or lubricant is mixed into gypsum, the strength itself can be improved, but it has the disadvantage that other physical properties of the gypsum change. Furthermore, when mixing natural fibers such as hemp into plaster, the tensile strength of natural fibers is lower than that of synthetic fibers, so the strength cannot be increased unless there are many plates for mixing the plaster. Moreover, since the single fibers of natural fibers themselves are thick, in the case of a raw car, the inside of the fibers is easily exposed to the molding surface due to the Mg that has entered the surface of the mold, and the exposed tB fibers tend to be compounded (intermediate development). The molding surface of the mold (or mold) is damaged, and the surface texture of the exposed fiber end becomes uneven. ! This method has drawbacks such as the fact that the corresponding part of the 1-manufactured broom tends to be defective due to r-fu.

Furthermore, if the glass fibers are made larger in the plaster, the strength of the model, prototype, etc. will be slightly improved, but since the glass fibers are rigid, the ends of the glass fibers that have entered the surface area will be In the case of a model, the appearance of the mold may be spoiled by protruding on the surface, and in the case of a K-type or intermediate mold, there is a disadvantage that the molding surface of the mold to be replicated is stuck.

The present invention has excellent strength properties, flexibility, and lightness.

By cutting carbon fibers with low thermal expansion and extremely small diameter into predetermined lengths, and evenly dispersing and mixing them into the hardened gypsum matrix at a predetermined weight ratio, a mold master or In the intermediate type, the expansion rate during curing,
By lowering the expansion coefficient and thermal expansion coefficient at the time of demolding after drying, the precision of mold replication is improved, and the mechanical strength of the material is increased, thereby reducing the resistance to external mechanical forces.
It has increased both its strength (durability) and its strength (durability) against internal stress caused by thermal strain. Similarly, by increasing the mechanical strength of models, parts with rough shapes can be prevented from being broken or damaged due to external forces during storage or handling, and this is particularly important in reproduction models. By increasing the reproduction accuracy (dimensional accuracy), it has become possible to produce highly accurate moso.

The plaster models and prototypes to which the present invention is applied include pressing, casting, cutting, grinding, plastic working, laser processing, etc. of metal, non-metallic, inorganic and organic materials, and other chemical processes such as various A-electronic processes.・In the case of plaster models for all physical material processing and those that utilize five during processing, this includes the prototype for foaming the mold. Even if a mold is used during the molding process, if the shape of the product is almost the same as the base stone (or material) used to mold the mold, C.
When the number of molds is very small, one or a few, such as A-family materials and commemorative Kaaps, they are included in models and model apA types. In particular, models include electrical equipment, transportation equipment, chemical equipment, processing machine tools themselves, and models thereof.

In addition, as the master mold for molds and their intermediate molds, we use ceramic casting molds, potter's wheel molds, and press molds.

Paper container molds made from aqueous suspensions of paper valve slurry and 7-choin ceramics, used for molding molds that utilize the water absorbing properties of plaster, such as press molds, and synthetic molds. Rubber products, plastic products, non-ferrous metals Fi1
The products include those used for press molding, injection molding, casting molding, and extrusion molding of so-called fine seven mix products that do not contain clay as raw materials, and also include aircraft fuselages and automobiles. Prototype for body sheet metal press mold,
It includes the original form (first form sample fist design) for producing the original form, or an intermediate mold layer.

Furthermore, the type of carbon fiber used in the present invention may be polyacrylonitrile-based, pitch-based, rayon-based, or lignin poval-based, but carbon fibers that form a pattern or increase the strength of the master mold for molding may be used. High-strength or high-elasticity carbon fiber is desirable, specifically tensile strength of 200
]cgf/mm2@g/mm2) or more, tensile modulus of elasticity 2
0. OOOkgf/mm2 (g/mm2 or more is desirable).

In the present invention, it is extremely important to uniformly disperse and mix the carbon fibers, which tend to form into nodules, in the gypsum matrix and the matrix of the matrix without forming nodules in the form of single fibers. From this point of view, the length and weight proportion of the carbon fibers to be incorporated into the gypsum matrix as reinforcing material relative to the gypsum are determined.

The carbon fibers are dispersed into countless single fibers and mixed into the gypsum matrix of the base material, but based on the theory described below, the length of the carbon fibers can be 5 to 200 m, preferably 5 to 100 m. is necessary.

Figure 1 shows 100 parts by weight of gypsum and 60 parts by weight of water.

Made from the proportion of 0.5ffiit part of carbon fiber 15a+m
A graph of the test results showing the relationship between the length of carbon fiber and bending strength (bending strength) in a gypsum test piece measuring 25 mm It can be seen that the bending strength suddenly decreases.Here, the length of the carbon fibers dispersed and mixed into the gypsum matrix of the base material is 5 to 2.
The reason for limiting the length to 00 is that if the length is less than 5 gg, the total adhesion area between the gypsum particles of the base material and the carbon fiber single fibers will be insufficient, and the strength of the model or mold prototype will not be sufficiently improved. If the length is longer than 200 m, it will be difficult to handle when stirring the discrete powder and water into single fibers or when laying it up by hand, and it will also be difficult to handle it when stirring the discrete powder and water into single fibers or when laying it up by hand. This is because dispersion becomes difficult.

When casting work is required, the length of carbon fiber is 100 mm.
If it is not less than m, it will be difficult to work. Therefore, in the case of an intermediate type, it is necessary to use Loosm carbon fiber.

First, 5 to 100 carbon fibers manufactured by a conventional method are
slI, or cut into lengths of 6 to 200fl, and then made into countless single fibers using a prescribed method! ! Forgive me.

An example of a method for dispersing bundled carbon fibers into jlt fibers is as follows. First, a bundle of carbon fibers is heated in an oxidizing atmosphere to oxidize and remove the sizing agent for handling stabilization applied to the surface, or the sizing agent is removed by washing with an acetone solvent. The heating temperature when removing the sizing agent by heating is determined relatively depending on the relationship with the sizing agent applied to the surface, but it is around 300°C, which is the general maximum safe use temperature for carbon fiber. It is desirable to do so. The carbon from which the sizing agent has been removed by heating is treated with carbon fibers containing countless (usually 1,000 to 24,000) very small diameter (usually 1 to 10/7111) carbon fibers that make up the carbon fibers.
easily dispersed into

Next, the sizing agent is removed and the carbon fibers cut to a predetermined length are placed in a water tank, and the sizing agent is removed by heating when the carbon fibers are gently rotated by a stirring blade while applying ultrasonic vibrations. Carbon f8 becomes more easily dispersed
Due to the synergistic effect of ultrasonic vibration and rapid stirring, the fibers are dispersed into countless single fibers with extremely small diameters without forming any lumps. During stirring, the rotation speed should be set at 40 to 60° in a water tank with a diameter of about 60C1B so that the carbon fibers are not attached by the stirring blade.
It needs to be in rpm. After the dispersion treatment, several cans of dispersed single fibers are taken out from the water tank, dehydrated and dried.

Another method for dispersing bundled carbon m-fibers into single fibers is to pre-size the carbon fibers with a water-soluble sizing agent. That is, a bundle of carbon fibers sized with a water-soluble sizing agent is cut into lengths of mmfr: 5 to loosms or 5 to 200 tm, and a total of 1 carbon fiber that matches the mixing ratio of one time is cut in advance. When the weighed carbon fibers are put into a container containing water that matches the mixing ratio of 1@ and are gently stirred with a stirring blade, the water-soluble sizing agent applied to the carbon fibers is immediately absorbed. The carbon fibers are eluted into the water and self-diffused, and the bundle-like carbon fibers are uniformly dispersed into countless single fibers with extremely small diameters without forming lumps in the water due to the pushing action of the stirring blades. Even in the case of this method, the rotation speed must be set at 4Q to 60 rpm in a container with a diameter of about 60 cm to prevent the carbon fibers from being damaged by the stirring blades during stirring.

When dispersing Charcoal A gypsum slurry is created by adding additives such as water reducing agents and mixing and stirring.

Next, to describe a method for making gypsum slurry containing dispersed carbon fibers mixed into single fibers, the ratio of carbon fiber to gypsum powder should be 0.01 to 2.4% by weight (hardened When converted to the ratio of carbon 21 to the plaster of the base material of the model foam or molding model, it is approximately 0.0.
08 to 2.0% by weight), preferably 0.1 to 1
．． It is necessary to reduce the amount to 0% by weight. Figure 2 shows the required needle part (various ¥fX amount parts) of carbon fiber with a length of 20 mm for a raw material mixture of 100 parts by weight of stone arm powder and 2 parts by weight of 60 parts of water.
15IIIm x 25mm x 250mm mixed in the proportion of
(i') It is a graph of paper film results showing the relationship between the weight percent of mixed carbon fiber to gypsum powder in a gypsum test piece and bending strength. As is clear from FIG. 2, the greater the fIk ratio of carbon fibers mixed in the gypsum powder, the greater the bending strength.

Here, the mixing ratio of carbon uA fibers to gypsum powder is 0.
The reason for setting it at 0.01 to 2.4 weight percent is that if the mixing ratio of carbon fiber is less than 0.01 weight percent, the ratio of carbon fiber to gypsum powder is too small, and the model or molded powder prototype may not have sufficient strength. It is not possible to improve the situation. Furthermore, if the ratio of charcoal-Jg woven fibers mixed exceeds 2.4% by weight, the ratio of carbon fibers will be too large when making gypsum slurry or slurry, and carbon fibers will be mixed into the gypsum slurry or slurry as single fibers. 1lli such as not being able to mix in the state and hand lay-up? This is because layer work becomes difficult. In the case of an intermediate type, the carbon fiber mixing rate is set to 0.0% to 1.0% based on the gypsum powder. 1.
If it exceeds 0%, the carbon fibers cannot be uniformly dispersed in the gypsum slurry in the form of single fibers, making it easy to form carbon fiber nodules, and the fluidity when pouring the gypsum slurry into the matrix becomes poor, making casting difficult. This causes carbon fiber lumps to form inside the molded intermediate mold, making it impossible to satisfy the function of a dense interspace deaf.

Then, by removing the sizing agent mentioned above and using the carbon fibers that have been dispersed into fibers in advance, the carbon fibers are placed in a mixing container to create a stone slurry with uniformly dispersed carbon fibers. Fill the container with necessary additives such as water suitable for the amount of mixing at one time, a hardening retardant, a water reducing agent, and an expansion/contraction control agent such as filler and silica powder (calcium carbonate-limestone powder). A pre-measured amount of carbon fibers (3) dispersed into monofilaments is placed in the container, a predetermined amount of gypsum powder is added to the topmost bale, the container is attached to a vacuum stirrer, and the stirring blades are turned at low speed. When mixed and stirred by rotation, a stone/chikaratoshit can be obtained in which carbon single fibers are uniformly dispersed within the gypsum peat without forming any lumps. !I
The reason why the carbon fibers are uniformly dispersed without producing I'2 is that the ratio of carbon fibers to gypsum powder is extremely small.

And plaster! There are many ways to manufacture a model or a prototype, but in some cases, the desired prototype! or an original jinbutsu (manifestation) that approximates the model is made by the pressing method.
Place carbon fiber inside this matrix made of clay, plaster or plastic, which has a 18B or male mold part that is slightly larger or smaller than the target model or original model. The above-mentioned gypsum slurry in which gypsum is uniformly dispersed is poured, discharged for a predetermined period of time, and after hardening, the matrix is separated and removed,
After drying sufficiently at a predetermined temperature, a hardened gypsum body with carbon fibers uniformly dispersed inside is obtained. In the case of a hardened body, plaster is further applied to it to obtain a desired plaster model type or IiX type. Lay it up by hand coating on a suitable plastic core mold to obtain a thick hardened product, then cut it out to make a slightly thicker model or prototype, and from this, use the above-mentioned method. The above process may be carried out after obtaining a mother mold by copying.

This process of creating models and prototypes may be repeated several times. In either case, in the case of casting (casting) work, the amount of carbon fiber mixed in is up to 1% of the gypsum powder, but
In the case of painting work, 2.4% is possible.

The diameter of a single carbon fiber fiber is extremely small and it has great flexibility, so even if the protrusion of the carbon fiber is exposed on the surface of the model or the molded surface of the original grave, it will hardly be exposed. There's no problem. However, if it is necessary to prevent the ends of the carbon fibers from being exposed on the molding surface, especially in the case of a master mold that will be subjected to a subsequent replication process, it can be poured into a mother mold as described above to serve as the base noodle of the master mold. When molding a gypsum hardened body, carbon j is added into the matrix.
3. Pour pure gypsum slurry with no fibers mixed in to form a thin layer in advance, and then pour stone base mud mixed with carbon fibers to form a hardened gypsum body. It is possible to prevent the ends of the carbon fibers from being exposed. The same thing can be said about models.

Here, a case will be described with reference to FIG. 3, in which a large number of molds made of FM are manufactured for casting a plastic plate-shaped body having a carved pattern.

First, as described above, a plaster model 1 is made using carbon fibers uniformly and pure gypsum on the inner and outer surfaces. This IIx type 1 t5! Duplicate the lower archetype 2 from the aspect U
make This lower prototype 2 is now S precision CU construction,
Also called master type. From this lower master mold 2, a female mold 3 having an upper male mold part and a lower mold 4 are manufactured around R. This lower female mold 4 has a plaster slurry injection 05. The combination of the upper and lower female molds 3.degree. 4 is the so-called lower case mold 6. Carbon*a was evenly distributed into this case mold 6 from the stone slurry inlet 5. Inject the slurry. When injecting 1 stone ↓ slurry at normal pressure (atmospheric pressure), 1
The case type 6 shown in f3t'N (c) must be rotated half upside down. After curing for a predetermined number of hours, the upper mold 3 and the lower mold 4 are separated to take out the desired lower mold. Turn the head and create an upper model from the top of the model. From this upper model, create a H-type light case, and cast stone + J slurry on it. 2 colored molds 8
get. 8. The lower mold 7 is combined to form a mold 9. The master mold or intermediate mold made of carbon T51 fiber-reinforced plaster according to the present invention has a small tensile coefficient, a volume expansion skewer during the curing process, and a small volume after drying. If you use plaster in which the above-mentioned carbon fibers are evenly dispersed and mixed in a total of 3 times of shape duplication as shown in U, it is possible to reproduce a high-precision mold with little dimensional change from the original mold to the mold. becomes possible.

Moreover, carbon l! When a gypsum slurry in which FM is uniformly dispersed is made, it is troublesome to accurately measure the minute amount of carbon fiber each time the gypsum slurry is made. Therefore, the carbon fibers, which are lightweight, highly buoyant, and difficult to handle, were mixed and dispersed uniformly into the gypsum powder in advance using circulating jet air flow or rocking rotation. It may also be used as a raw material gypsum powder. This eliminates the need for the troublesome operation of measuring only a small amount of carbon fibers suitable for the amount of mixing once each time gypsum slurry is made.

To specifically describe the mixing method using a jet air flow that changes the ring, the gypsum powder and the carbon fibers dispersed into 1C fibers are mixed into the gypsum powder and the carbon fibers are mixed into G, OL or 5G.
When the gypsum powder and the carbon fibers separated into single fibers are poured into the mixing chamber at the correct ratio, the gypsum powder and the carbon fibers are dispersed by the jet air stream and circulated many times to be properly mixed. If Y11 is collected from the air stream by a cycler or a back filter, will it turn into stone? powder and /iiζ
A gypsum powder containing carbon fibers uniformly mixed with 11 carbon fibers is obtained. Here, the pressure of the jet air flow is 2 kg! , M” (x ic/c+g
”) is required, and if the air pressure is increased, the thrust force between the gypsum particles or between the gypsum particles and the carbon fibers will increase, causing a single stone particle and carbon fiber to ◇ In addition, as another method for uniformly mixing carbon fibers with gypsum powder, lifting rotation is used as a method for γ・L. There is a way.

As shown in Fig. 4, gypsum powder and stone 1 (1 piece of charcoal that has been crushed by a single fiber) are placed in a bag 11 that can be bent freely. Put 4 liters of bamboo in the ratio of 0.1 to 5 liters,
tilJ! When 412 is rotated by the swing shaft 14 attached to 13, the mixture inside the bag body 11 is accelerated, and the magnitude and direction of the momentum change arbitrarily. As a result, the gypsum powder and carbon kM Aa in the bag body 11 are uniformly mixed.

Incidentally, when mixing the carbon la fibers into the gypsum powder, it is also possible to simultaneously mix necessary additives such as a hardening retardant and a water reducing agent.

In addition, the above-mentioned gypsum powder is made by uniformly mixing and dispersing carbon fibers dispersed into countless single fibers in the gypsum powder, but water-soluble sizing materials such as polyvinyl pyrrolidone and polyvinyl alcohol It is not necessary to calculate the number of carbon fibers sized with the agent to 45 fibers in advance, since the water-soluble sizing agent has the property of releasing γB into water and self-dispersing when making gypsum slurry. It can be mixed into the stone/saving powder inside the bag as a bundle.

Furthermore, when using carbon slag in gypsum powder,
When using powder with the raw material surface τ mixed and dispersed at a higher proportion than the above ratio (upper limit: 51%), mix the square powder again at the time of use, and add the gypsum powder and charcoal fJaM to the gypsum powder. Carbon F! fiber is 0.1 to 1%
Alternatively, it must be diluted to a concentration of 0.1 to 2-4% by weight, but this method can reduce the transportation cost of stone mixed with carbon fibers; can.

Here, the ratio of carbon fiber to gypsum powder is set to 0.01 to 5 m%, because if it exceeds 52 iHa%, the mixture in the form of single fibers will be 1].
This is because it cannot be used as a reinforcing material as it is. When using it as a mold original 1') without diluting it, the ratio of charcoal smoke to the stone is 0.01 to 1! ii % or 0.01 to 2.
It is assumed to be 4 times fi%.

When plaster mixed with carbon fiber is used as a material for a model, rye, or mold, the Σ tension during hydration hardening is small, and the sigma tension is small when the mold is removed after semi-dry 4f'J4'ff4 is completed. Due to the E-stretch wheel and the small expansion coefficient when used, the accuracy of the 1'-thin reproduction product, which is repeatedly reproduced by inserting 14 sheets into the original material, is high and accurate reproduction products can be produced. In addition, since the coefficient of thermal expansion is small, expansion and contraction due to temperature changes is small, making it a highly accurate model or prototype. Therefore, even if the mold is repeatedly replicated several times, the reproduction error between the first mold and the tin mold is small and the quality is good. This point is most important for general industrial models or original materials.

In addition, when producing plaster models and ffXFJI,
In addition to the casting method, a method of manually applying plaster slurry, similar to the FRP solder lay-up method, can also be applied, but in the case of 5-layer plaster models (generally large ones, In this case, great strength is required, so the upper limit of the length of carbon fiber mixed into the gypsum slurry or slurry is 200 m, and the upper limit of the amount of carbon fiber mixed with hydrate is 2.0 times ( There is no problem in the work even if the number is increased.

The model itself is made of metal, wood, or a natural product, and is molded into the above-mentioned plaster slurry or slurry by a molding method to obtain a stone-shaped horizontal copy i+u. Copies and molds can also be made.

Next, the original Il! Examples and comparative examples of lJ are given below.

Example 1 After treating polyacrylonitrile-based fibers to 'A' at about 300°C, they were further heat-treated at about 130°C in a nitrogen gas atmosphere to graphitize, and AA 4:1 miscellaneous particles with a diameter of about 7 μm were
A bundle of 00 charcoal fibers was used. This charcoal? IFJ
The physical properties of the miscellaneous material are tensile strength 300kgf/m+y+” (
IC/mm2), tensile modulus of elasticity 23. OOOkgf/m
m” (IC/mm2), density 1°75 dino, IAea
Person in charge 771 0. lXl0-'7'Q, Jden>jJ rate 15Kca/mhr"Oα7.4sw/wax),
Specific heat 0.17Q &engineering/g'0 (to 0.71: r/kg*
K). This charcoal (X < ta 1 m) was cut into lengths of approximately 20 lengths, and dispersed into countless pieces of charcoal under water using the Kaito action of ultrasonic vibration and stirring. β right turn powder machining O
O parts by weight, 60 parts by weight of water.

0.1 part by weight of carbon fiber and 0.2 part by weight of borax (curing agent) are mixed and stirred to create a gypsum slurry in which carbon fiber single fibers are uniformly dispersed. A body with approximately the same shape as an external plaster mold for casting a ceramic plate on a potter's wheel by pouring it into a matrix was obtained. This was made into a prototype with some modifications.

In this plaster model for external bones, carbon fiber single fibers were uniformly dispersed over the entire cut cross section, and the state of dispersion was such that it could be seen with the naked eye.

Example 2 A gypsum slurry in which single fibers of carbon fibers were uniformly dispersed was made under the same conditions and method as in Example 1, and pure gypsum slurry without carbon fibers mixed in was poured in advance while rotating the matrix at low speed. A thin film with a thickness of 1 to 3 mm is formed in advance, and then the rotation of the matrix is stopped and plaster slurry mixed with carbon fiber is poured in to form a plaster prototype for the external bone for molding a ceramic plate. A body with approximately the same shape was obtained. This was made into a prototype with some modifications. The outer circumferential surface, which is the molding surface of this outer gypsum master mold, was sewn with a thin film made of pure gypsum, and no carbon fibers were exposed on the molding surface.

Example 3 Meliacrylonitrile fibers were heat-treated at about 300°C, then special heat-treated at about 2,500°C in a nitrogen gas atmosphere to graphitize them, and single fibers with a diameter of about 7 μm were sized with polyvinyl biwaridone to produce about Carbon fibers made of 6000 carbon fibers were used. The physical properties of this carbon fiber are
Tensile strength: 250 kgf/mmm2 (IC/mm2), tensile modulus: 35. OOOkgf/mmmm2(/am2
), density 1. '17 g/am3. ka expansion coefficient −O,
LXIO/'Q, thermal conductivity 1. OOKCal/m*h
r*'0 (116W/m, eK), specific heat 0.17 Q
a +, /g'O (0,71 kJ/kg@lc). This bundle-shaped carbon G4 fiber was cut into a length of 25 gourds,
The ratio of carbon fiber to 100 parts by weight of β-gypsum powder is 0.
Weigh the carbon fibers in advance to make 3 parts by weight,
When this carbon fiber is put into a container containing pre-measured water and stirred auxiliary, the bundle-like carbon fibers are self-dispersed and dispersed into countless units of tBm. It was evenly dispersed in water. After that, gypsum powder,
Borax (hardening retardant) and Melmen manufactured by Showa Denko Co., Ltd.)? -2O (water reducing agent) was mixed and stirred to produce 100 parts by weight of gypsum powder, 60 parts by weight of water, 0.3 parts by weight of carbon fiber, 0.12 parts by weight of hardening retardant, and 0.0 parts by weight of water reducing agent.
A homogeneous gypsum slurry consisting of 2 parts by weight was prepared, and this gypsum slurry was poured into a matrix to obtain a hardened gypsum shape that was approximately the same as a cast gypsum blank for molding a ceramic ellipsoid. Tatsuko's shape was placed on a rotating ellipse macro, and the model was modified using a plaster cutting tool. This cast molding layer plaster 8I! The state of dispersion of the carbon fibers in the prototype was almost uniform as in Example 1.

Comparative Example 1 100 parts by weight of β-gypsum powder, 60 parts by weight of water, 0.2 parts by weight of borax
Mix and stir in proportions of parts by weight to make pure gypsum slurry that does not contain carbon dioxide, and pour this gypsum slurry into a case mold to obtain an outer gypsum prototype for potter's wheel molding of a ceramic plate. Ta.

Next, examples and comparative examples of model reproduction of the present invention will be given.

After heat-treating the practical polyacrylonitrile fiber at about 300°C, it was further heat-treated at about 1,300°C in a nitrogen gas atmosphere to graphitize it, and it was made into a bundle of about 6,000 single fibers with a diameter of about 7 μm! Carbon! A male was used. The physical properties of this carbon fiber are 5
[Tensile strength 300kgf/mm (Kg/ml112)
, tensile modulus of elasticity 23. OOOkgf/mmmm2 (7m
m2 density 1.75 glon, linear y tensile coefficient -〇, I
X 10/”O.

Thermal conductivity 1.5Ka &l/m*hre'c (17,
45W/m5K).

Specific heat 0.17cal/g”C (0.71kJ/kg*K
)Met.

This carbon fiber was cut into lengths of about 20 sieves, and dispersed into countless single fibers in water by the synergistic action of ultrasonic vibration and stirring. β gypsum powder 100 parts by weight 1 water 60 parts by weight,
Mix and stir 0.1 part by weight of carbon fiber and 0.2 part by weight of borax (hardening retardant) to create a gypsum slurry in which carbon fiber am is uniformly dispersed. A
A replica plaster male model of a gas turbine turbine blade was obtained by pouring it into a female mold. In this replica plaster male model, single fibers of carbon ta fibers were uniformly dispersed over the entire area including the cross section, and this dispersion state (to the extent that it could be seen with the naked eye).

Comparative Example 2 A pure gypsum slurry containing no carbon fibers was prepared by mixing and stirring 100 parts by weight of β-gypsum powder, 60 parts by weight of water, and 0.2 parts by weight of borax. A replica plaster male model of the turbine blade was obtained by pouring it into a female mold.

The rate of change in length at each temperature and the replication accuracy during detachment of the replica plaster male models of Example 4 and Comparative Example 2 were as follows.

As for the rate of change in length, as shown in Figure 5, the maximum heat generation of the model (53, 2
℃), in addition to hydration volumetric expansion, there is thermal expansion due to temperature change.
o for w, 33 simple) had expanded.

In addition, when drying in a G8 air dryer at 50°C for 20 hours and a half, cooling to room temperature 23.5°C, and removing the mold, the reproduction accuracy of the conventional horizontal type was 0.025% (0 for 500 parrots).
．． 125 m), whereas the model according to the present invention had a volumetric expansion of 0.018% (0.09 m for 500 cods).
) The volume was 1 tension.

After that, it was dried for about 2 weeks in a hot air dryer at 50°C. Regarding the reproduction accuracy, the conventional product had a dry yield M of 0.06 m for 500111II (therefore, the volume expansion was 0.06
5m) L, whereas the product of the present invention had a drying shrinkage of 0.04m for 5°OW (therefore, the body @R expansion of 0.05m for the matrix); It was demonstrated that the volumetric expansion was smaller at all stages compared to the product.

The physical properties of each of the plaster molds of Example L2.3 and Comparative Example 1, such as bending strength, water absorption capacity, difference in fracture temperature in the atmosphere, bulk specific gravity, and expansion coefficient upon curing, were as shown in the table below. .

Hereinafter, the margin water absorption capacity is the weight percentage of water absorbed when the test piece is immersed in water at room temperature and pressure.

The fracture temperature difference represents the minimum temperature difference that will result in fracture when a test piece that has been heated in a high-temperature atmosphere is quickly taken out indoors and left in a room-temperature atmosphere.

The coefficient of expansion upon hardening is the ratio of the change in length to the matrix when gypsum slurry is poured into the matrix, hardened, and deafened, and then measured immediately before drying.

As is clear from the above table, the gypsum mold mixed with carbon fiber has significantly improved bending strength and the difference in fracture temperature in the atmosphere compared to the gypsum mold without carbon fiber mixed, and has also improved in other physical properties. It turned out to be excellent.

FIG. 5 is a photograph taken with a scanning electron microscope of a thin section made from a cut surface of the hardened gypsum body of Example 1 at a magnification of 2000 times. The elongated straight cylinder extending from the upper left corner to the center is the mixed carbon chapter fiber, and the fragment-like crystals are β-type dihydrate gypsum.

Figure 7 shows Example 1 except that α-type gypsum powder was used.
This is a scanning electron micrograph of the same image as Iff, magnified <2000 times.

Fig. 8 shows a 15N x 25w x 25 (1+
It shows the relationship between the elapsed time and transverse rupture strength when a gypsum test piece of s was subjected to a bending test using a bending test device, and is the result of trial 12+ when the weight ratio of mixed carbon fiber was used as a parameter. As is clear from the graph in Figure 8, as the proportion of mixed carbon fiber increases, the transverse rupture strength increases, and the brittleness of simple rupture at the maximum transverse rupture force is eliminated, resulting in the so-called stickiness of Song wood. I understand that. The span of this test was 200#+l+, and the load was applied to the center.
The displacement speed of the loading point was 1 ts 7 m i rr.

Figure 9 shows curves showing the rate of change in length at various temperatures for a pure gypsum specimen and a gypsum specimen reinforced with carbon fibers, and for a gypsum specimen reinforced with carbon fibers. It can be seen that the length change (expansion) rate is slightly smaller in both positive and negative cases than the length change (expansion) rate of the gypsum specimen without carbon fibers mixed therein. This is understood to be because carbon fibers with a coefficient of thermal expansion of almost zero are inserted between each particle of gypsum, and this carbon fiber suppresses the expansion or contraction of gypsum. Therefore, the gypsum master mold or model mixed with carbon fibers exhibits less expansion or contraction due to temperature, and the dimensional accuracy of the replicated model or intermediate mold is improved.

By greatly improving transverse rupture strength and transverse rupture strength, the material mechanical strength of the model or original model is increased, and partial models with complex shapes that were conventionally damaged by external forces during storage and handling are now available. The mechanical strength of the parts that are susceptible to breakage is increased, thereby preventing damage to the model or original model, extending its life, and making it easier to transport and handle. Furthermore, due to the significant improvement in mechanical strength,
It becomes possible to reduce the thickness of the convex portions, etc., and as a result, it becomes possible to manufacture a model or prototype having a complicated or delicate shape.

In addition, the difference in fracture temperature in the atmosphere improves when carbon fiber is mixed in. Although the plaster itself expands to a certain degree due to temperature rise, the carbon fiber itself hardly expands. At the same time that a tensile force is applied to the plaster in its length direction, a compressive force is also applied to the plaster, which creates internal stress in the length direction of the carbon fibers, creating a state where prestress is introduced just like in P3 concrete. It is understood that this is for the purpose of

A large increase in the breakdown temperature difference in the atmosphere means that the plaster model or model can withstand a large temperature difference, and the drying temperature of the model or model or intermediate model after molding. It becomes possible to raise the Therefore, it becomes possible to shorten the drying time of the model, master mold, or intermediate mold for each molding, and the time required for manufacturing and duplicating the horizontal mold or master mold is shortened.

In summary, the present invention has the following effects.

(1) Gypsum ywt according to the present invention, in which carbon fibers having a length of 5 to 200 mm are uniformly mixed into the base material plaster at a ratio of o, o o a to 2.0% by weight based on the plaster; m
Compared to the conventional master mold made of pure gypsum, both the expansion wheel and the coefficient of thermal expansion during demolding due to hydration hardening are smaller, so the entire process of replicating from the master mold to the case mold and mold It is possible to manufacture highly accurate molds with little integration error.

(2) Also, by greatly improving both the bending strength and toughness, the mechanical strength of the model or original model is increased, and complex structures that were conventionally damaged by external forces during storage and handling can be improved. Breaking or damage of a shaped part or a part that is easily broken is prevented, and the life of the model or prototype is extended.

In addition, the significant improvement in mechanical strength makes it possible to reduce the thickness of convex portions, etc., which in turn makes it possible to manufacture models or prototypes with complex or delicate shapes.

(3) The expansion coefficient of gypsum containing carbon fibers uniformly dispersed in the form of single fibers during hydration and hardening or upon completion of drying, and the coefficient of thermal expansion when used as a matrix, compared to pure gypsum. Since the size of the model is small, the dimensional accuracy of the model (especially a reproduction model) according to the present invention is improved, and it becomes possible to manufacture a model with the desired dimensions.

(4) Since carbon fiber has rich flexibility, even if carbon fiber is mixed into a plaster model, its surface will be smooth and moderately soft. Therefore, the machinability of the model or prototype is extremely good, and it can be freely cut into a desired shape.

(5) In the case of a prototype type or an intermediate type, when manufacturing it, pure gypsum slurry is poured into the matrix to form a thin calendar, and then gypsum slurry mixed with carbon fiber is poured in to form the prototype type. Alternatively, a protective layer made of pure gypsum is formed on the molding surface of the intermediate wheel to prevent the ends of the carbon fibers from being exposed to the molding surface. By configuring the original model or intermediate mold in this manner, it is possible to prevent the surface (molding surface) of the mold to be replicated from being damaged.

In the case of cross wheels, coating the surface with a thin layer of pure gypsum prevents the aesthetic appearance from being spoiled due to exposure of single carbon fibers.

(6) As the reinforcing material for the model or original, we use carbon fiber, which is light in diameter, small in size, strong, and highly flexible, so even if the ratio of reinforcing material to the plaster is small. The strength of the model or prototype against mechanical external forces and thermal inhomogeneity can be increased, and even large-sized bodies can be manufactured at low cost, and molding operations can be facilitated.

(7) Since carbon fiber is mixed in as a reinforcing material and has the property of burning out when heated, plaster moldings, master molds, and intermediate molds that are damaged or become unusable during use are ,
By pulverizing the material and subjecting it to gentle heat treatment over a long period of time, only the carbon fibers mixed inside can be easily burned off and the hardened gypsum material can be used. In this regard, if a material that does not have heat-burning properties such as glass fiber is mixed in as a reinforcing material, it is extremely difficult to remove only the mixed reinforcing material and regenerate or reuse the hardened gypsum. , or it is impossible.

(8) Carbon fibers are cut into a predetermined length and dispersed in advance into countless single fibers, and gypsum powder and the carbon fibers are dispersed into single fibers having a predetermined weight ffi ratio with respect to the gypsum powder. By introducing the fibers into a circulating jet air stream to uniformly mix the two, and then collecting them, the carbon fibers, which have been dispersed into single fibers, are uniformly mixed and dispersed within the gypsum powder. It is possible to eliminate the need for measuring only the Wl and amount of carbon fibers that are suitable for one mixing amount each time gypsum slurry is made.

[Brief explanation of drawings]

Figure 1 is a graph showing the relationship between the length of carbon fibers mixed in hardened gypsum and the bending strength of a hardened gypsum test piece. FIG. 2 is a graph showing the relationship between the weight ratio of carbon fiber mixed in the plaster to the plaster and the bending strength of the plaster test piece. Figure 3 shows the molding process of a plaster mold for a plastic casting plate with an engraved pattern, (a) is the original, (b) is the lower mold, and (c) is the lower mold. Case type, for)
are sectional views of the molds. FIG. 4 is a diagram showing the principle of a mixing method using rocking rotation. FIG. 5 is a graph showing the relationship between the elapsed time during molding of a carbon fiber-reinforced gypsum model and a pure gypsum model and the expansion coefficient during hydration and hardening. #! FIG. 6 is a scanning electron micrograph of a gypsum sample piece when β-type gypsum powder is used, and FIG. 7 is a similar photograph when α-type gypsum powder is used. - Fig. 8 is a measurement graph showing the change in transverse rupture strength over time in a bending test of a plaster mold test piece in which the ratio f2 fn of carbon fiber mixed in the plaster mold to the plaster was used as a parameter. FIG. 9 is a graph showing the rate of change in length at each temperature of a pure gypsum test piece and a carbon fiber reinforced gypsum test piece. (Explanation of symbols of main parts) 1: Original mold 2, lower light (intermediate mold) 6: Case mold for lower mold (intermediate mold) 9: Molding mold 11: Bag body swings 12° Board 13: Rotates Axis drawings, 7) Engravings, changes in content 1. ) No. 0 Diagram ui・tsujoshu (Contents: No changes 6) Procedural amendment dated 11322, 1980 Mr. Manabu Shiga, Commissioner of the Patent Office':&:'1(
Chief Adjudicator of the Japan Patent Office) (Chief Fraud Office Fujinomiya) 3. Relationship with the Xi incident to be amended Patent applicant 4.
500 persons 9 The detailed declaration of the application is amended as follows. 1. The claims on page 1, line 7 to page 8, line 15 are amended as follows. (1) A length of 5 to 200s+ within the gypsum structure of the base material.
A product made of carbon fiber-reinforced gypsum, characterized in that carbon fibers of s are dispersed into single Jia+ fibers and uniformly mixed and dispersed in the plaster at a ratio of o, o o a to a, OZ amount %. Original or model copy. (2) A patent characterized in that carbon fibers having a length of 5 to 10 ossi are uniformly mixed and dispersed in the base material of plaster at a ratio of o, o o a to 0.9% by weight based on the plaster. A charcoal 3IC fiber-reinforced plaster model or M copy mold according to claim 1. (S to the base material stone' I - carbon fibers of 5 to 200 lengths are dispersed into single fibers in the structure and o to the plaster,
A carbon fiber-reinforced gypsum master mold characterized in that carbon fibers are uniformly mixed and dispersed in a proportion of o o a to 2.0% by weight. (4) A patent characterized in that carbon fibers having a length of 5 to 100 mm are uniformly mixed and dispersed in the base material of plaster at a hereditary ratio of o, o o a to 0.9 N to the plaster. A carbon fiber-reinforced plaster mold according to claim 3. (5) A patent claim characterized in that carbon fibers having a length of 15 to 30 mm are uniformly mixed and dispersed in the base material gypsum at a ratio of 0.05 to 0.3% by weight based on the gypsum. RG and mold for carbon fiber-reinforced gypsum molds according to item 3. (To O) The mold consists of a ceramic casting mold, a potter's wheel, a paper carton casting mold made from paper pulp slurry, and a mold that utilizes the water absorption properties of plaster, such as a press mold. A master mold for a carbon fiber-reinforced gypsum mold according to claims 3 to 5, wherein the mold is a plastic product 9-component rubber product. A master mold for a carbon fiber-reinforced gypsum i-molding mold according to claims 3 to 5, which is a mold such as a casting mold, an extrusion mold, or an injection mold, and has Pvf characteristics. (8) The molds are press molds, injection molds, etc. for so-called fine ceramic products that do not contain clay as raw materials.
The master mold for a carbon fiber-reinforced gypsum mold according to claims 3 to 5, which is a mold such as a &IJ-containing mold. (9) Carbon fibers of length to 100 length are dispersed into single fibers in the matrix stone 1iF structure, and the ratio of o, o o a to 0.9% by weight to the plaster is uniform. An intermediate mold for a carbon fiber-reinforced gypsum mold, characterized by being mixed and dispersed in carbon fiber. l5a), a patent claim characterized in that charcoal fibers having a length of 15 to 30 m are uniformly mixed and dispersed in the base material gypsum at a ratio of 0.05 to 0.3% by weight based on the gypsum. An intermediate amount for carbon fiber-reinforced gypsum molds as described in Range 9. (11) The mold is a ceramic casting mold, a potter's wheel mold, a paper carton casting kettle made from paper pulp slurry, or a mold that utilizes the water absorption properties of plaster, such as a press mold. Claims 9 to 10 are characterized in that
Intermediate mold for carbon fiber-reinforced gypsum mold described in Section 1. α2) The carbon fiber according to claims 9 to 10, characterized in that the mold is a mold such as a casting molding machine, an extrusion mold, or an injection mold for plastic products or non-ferrous metal products. Intermediate mold for reinforced plaster molds. (13) A patent characterized in that the mold is used to mold a press mold, an injection molding part, a casting molding temperature, and an extrusion molding eyebrow shape of a so-called fume ceramic product that does not contain clay as a raw material. An intermediate mold for a carbon fiber-reinforced gypsum mold according to claims 9 or 10. (14) Carbon ionization with a length of 5 to 200 mm in the plaster of the base material of the mold is dispersed into single fibers, and the plaster is omitted.
, o o a to 2.0% of the air temperature, and the surface layer of the mold is covered with plaster containing a smaller proportion of carbon fiber than other parts. Reinforced stone 7# model or model copy. (15), length 5 to 200s+ in the plaster of the base material of the mold
The carbon fibers of a are dispersed into single fibers and are uniformly mixed and dispersed at a ratio of 0.008 to 2.0% to the plaster, and the surface layer of the mold has a different proportion of carbon fibers. W, mold made of carbon fiber reinforced gypsum, characterized in that it is covered with less gypsum. (16) Carbon fibers with a length of 5 to loom are dispersed into single fibers in the plaster of the base material of the pot, and the carbon fibers are 0.0.
Carbon fiber-reinforced stone characterized by being uniformly mixed and dispersed at a ratio of 0.008 to 0.9% by weight, and the surface of the mold being covered with pure gypsum without carbon fibers mixed in: IT-made molding Intermediate mold for mold. (17) Carbon fibers dispersed into single fibers with a length of 5 to 200 m are added to the gypsum powder at a rate of 0.0 m to the gypsum powder.
Gypsum powder containing carbon fiber for use as a plaster model or model copy or original model, uniformly mixed and dispersed at a ratio of 1 to 5 times ft-. (18) Carbon fibers dispersed into single fibers with a length of 5 to loo+w are added to the gypsum powder at a rate of 0.
18. The carbon fiber-containing gypsum powder for use in plaster models, model reproductions, or master molds according to claim 17, characterized in that the carbon fiber-containing gypsum powder is uniformly mixed and dispersed in a proportion of 0.01 to 1.0% by weight. (19) Carbon fibers dispersed into single fibers with a length of 5 to 100 looms are added to the stone or gypsum powder at a rate of 0.0% relative to the gypsum powder.
A gypsum powder containing carbon fibers for intermediate molds made of gypsum, which is uniformly mixed and dispersed in a proportion of 0.01 to 5% by weight. (20), carbon fibers dispersed into single fibers of 5 to 100 lengths are added to the gypsum powder at a rate of 0.0% relative to the gypsum powder.
The carbon fiber-containing gypsum powder for use in plaster intermediate molds according to claim 19, characterized in that the carbon fiber-containing gypsum powder is uniformly mixed and dispersed at a ratio of 1 to 1.0 percent heavy duty. (21) Carbon fibers are cut into lengths of 5 to 200 m and dispersed in advance into countless single fibers, and then mixed with gypsum powder and 0.01 to 5% by weight of single fibers with respect to the gypsum powder. With the carbon fibers that are discrete? A method for producing carbon fiber-containing gypsum powder for a gypsum model, a model copy, or a master model, which comprises charging the powder into a circulating jet air stream to uniformly mix the two, and then recovering the powder. (2z), carbon fibers are cut into lengths of 5 to 200 $11 and dispersed in advance into countless single fibers, and gypsum powder and 0.01 to 5 weight M% of the gypsum powder are added. A method for producing carbon fiber-containing gypsum powder for a plaster model, a model copy mold, or a master model, which comprises putting the carbon fibers which have been subjected to w1 defeat into single fibers into a flexible bag and rocking and rotating them. (23), 5 to 100 carbon fibers! The carbon fibers are cut into lengths of II+ and dispersed into countless single fibers in advance, and the gypsum powder and the carbon fibers dispersed into single fibers in an amount of 0.1 to 5% by weight based on the gypsum powder are circulated. A method for producing carbon fiber-containing gypsum powder for intermediate molds made of gypsum, characterized in that the carbon fiber-containing gypsum powder is introduced into a jet air stream to uniformly mix the two and then recovered. (24), carbon fibers are cut into lengths of 5 to 100 degrees and dispersed into countless single fibers, and then mixed with gypsum powder.
For an intermediate mold made of gypsum, characterized in that the carbon fibers, which are dispersed into single fibers in an amount of 0.0 to 5% by weight based on the gypsum powder, are put into a flexible bag and rocked and rotated. A method for producing carbon fiber-containing gypsum powder. ” 2, page 10, lines 8 and 9, [...how to treat it as a copy, and how to make it into a product.・・・
” he corrected. 3. On page 14, line 8, ``Press mold, press mold,'' is corrected to ``...Rokuro mold, nibless mold,''. 4. On page 816, lines 16 and 177, "--using discrete powder and water to form a single fiber..." is corrected to "--forming discrete powder and water to Φ single fiber...". 5. On page 14, line 8, change "2.4% possible if..." to [2.4% if threatened! ! Correct that it is possible. 6. In the 11th line of page 28, "-lifting rotation as a fist method..." is corrected to "-as a method! dynamic rotation--". 7, page 28, lines 114 and 155, ``...carbon fiber 0.1 to 5% by weight...'' is corrected to ``...carbon fiber is juyuyu to 5 times i≦・ri.'' 8, No. Page 37, line 2: ``60 parts by weight of water, carbon fiber m
o, 1 part by weight...'' is corrected to ``Water aOZ part, star! (swelling inhibitor) 20 parts by weight, carbon fiber 0.1 part by weight ψ.''. 96, page 37, lines 12 and 133 “...60 weight f of water
1 part f, 0.2 parts by weight of borax...'' is corrected to ``+1 @ 60 parts water. B1 The drawing of the present application, Figure 3, is corrected as shown in the drawing attached to this document. 1 or more - Broom 3 Figure ( b) (b) Procedural amendment (IE published December 19, 1980, Mr. Manabu Shiga, Commissioner of the Patent Office (Patent Office 1y
(To the Chief Judge) 1 (To the Patent Office Examiner) 1. Indication of the case Patent Application No. 203764 of 1983 3. Relationship with the person making the amendment Patent applicant's address (residence) 756 Aii-cho, Yokkaichi City, Mie Prefecture 1
4. Agent 〒500 Amended the "Scope of Claims" stated from page 2, line 4 to page 49, line 13 of the written amendment submitted on November 22, 1980, as follows: do. (1) Carbon fibers with a length of 5 to 200 m are dispersed into single fibers within the gypsum structure of the base material, and 0.
A carbon fiber-reinforced plaster model or model reproduction mold characterized in that carbon fiber reinforced plaster is uniformly mixed and dispersed at a ratio of 0.008 to 2.0 fffffl%. (2) Carbon tB fibers with a length of 5 to XOO are uniformly mixed and dispersed in the base material gypsum at a ratio of o, o o a to 0.9 fkfit% to the plaster. A carbon fiber-reinforced plaster model or model copy according to claim 1. (3) In the gypsum structure of the base material, carbon ta fibers with a length of 200 to 200 mm are dispersed into single fibers and the gypsum structure is 0.0%.
A carbon #a fiber-reinforced gypsum g prototype characterized by being uniformly mixed and dispersed in a proportion of 0.008 to 2.0% by weight. (4) Carbon fibers having a length of 5 to 1001Is are uniformly mixed and dispersed in the base material of plaster at a ratio of o, o o a to 0.9% by weight based on the plaster. A carbon fiber-reinforced gypsum prototype according to claim 3. (5) A patent claim characterized in that carbon fibers having a length of 15 to 30 m5 are uniformly mixed and dispersed in the base material of plaster at a ratio of 0.05 to 0.3 weight ffi% to the plaster. A master mold for a carbon fiber-reinforced gypsum mold according to item 3. (6) The mold is a ceramic casting mold, a potter's wheel mold, or a paper carton casting mold made from paper pulp slurry;
Claims 3 to 5 are characterized in that the mold is a mold that utilizes the water absorbing properties of gypsum like a press mold.
Prototype for carbon fiber-reinforced gypsum mold described in Section 3. (a) The mold is a rubber product with plastic product 1. For carbon fiber reinforced gypsum molds according to claims N, items 3 to 5, which are molds such as casting molds, extrusion molds, injection molds, etc. for non-ferrous metal F4 products. prototype. (8) The mold is a press mold or injection mold for so-called fine ceramic products that do not contain clay as raw materials;
Is it a mold such as a casting mold? The carbon fiber-reinforced gypsum mold prototype □, (9) according to claims 3 to 5, wherein carbon fibers with a length of 5 to 100 m are formed into single fibers within the gypsum structure of the base material. An intermediate mold for a mold made of carbon fiber reinforced gypsum, characterized in that the intermediate mold is uniformly mixed and dispersed in a discrete state at a ratio of 0.008 to 0.9% by weight based on gypsum. (10) A patent claim characterized in that carbon fibers having a length of 15 to 30+ am are uniformly mixed and dispersed in the stone base material at a ratio of 0.05 to 0.3% by weight based on the plaster. An intermediate mold for a carbon fiber-reinforced gypsum mold according to Item 9. (11) Molding in which the mold uses the water absorbing properties of plaster, such as a spinning mold for ceramics, a potter's wheel mold, a paper carton casting mold made from paper valve slurry, or a press mold. Claims 9 to 10 are characterized in that they are molds.
Carbon fiber-reinforced gypsum mold layer intermediate mold described in Section 1. (12) The carbon according to claims 9 to 10, wherein the mold is a mold such as a casting mold, an extrusion mold, or an injection mold for plastic products or non-ferrous metal products. Fiber-reinforced gypsum mold layer intermediate mold. (13) A patent claim characterized in that the mold is used for press molding, injection molding, casting molding, and extrusion molding of so-called fine ceramic products that do not contain clay as a raw material. An intermediate mold for a carbon fiber-reinforced gypsum mold according to item 9 or 10. (14), carbon fibers with a length of 5 to 200 m are dispersed into single fibers in the plaster of the base material of the mold, and o,
o o Carbon fibers are uniformly mixed and dispersed at a mold temperature percentage of a to 2.0%, and the surface layer of the mold is covered with gypsum in which the carbon fibers are mixed in a smaller proportion than other parts. Reinforced plaster cast or model reproduction mold. (15) Carbon fibers with a length of 5 to 200 fins are dispersed into single fibers in the plaster of the base material of the mold, and 0.
Made of carbon fiber-reinforced gypsum, characterized in that the carbon fibers are uniformly mixed and dispersed at a ratio of 0.008 to 2.01ii%, and the surface layer of the mold is covered with plaster containing a smaller proportion of carbon LB fibers than other parts. prototype. (16), Length 5 to], OOm in the plaster of the base material of the mold
carbon fibers are dispersed into single fibers and placed against the plaster.
, o o a to 0.9% by weight, and the surface of the mold is coated with pure gypsum with no carbon fibers mixed in.
Intermediate mold for reinforced plaster molds. (17) A gypsum product made by uniformly mixing and dispersing carbon fibers, which are dispersed into single fibers with a length of 5 to 200 degrees, in gypsum powder at a ratio of 0.01 to 5 mbk% to the gypsum powder. Carbon fiber-containing gypsum powder for models, model reproduction molds, or master molds. (18) Carbon fibers dispersed into single fibers with a length of 5 to loosml are added to the gypsum powder at 0%
18. The carbon fiber-containing gypsum powder for plaster models, model copies, or originals as claimed in claim 17, characterized in that the carbon fiber-containing gypsum powder is uniformly mixed and dispersed at a ratio of 0.01 to 1.0%. (19) Add charcoal: A fibers into monofilaments of length 5 to 100% in gypsum powder to 0% against the gypsum powder.
Carbon fiber-containing gypsum powder for stone/W chain intermediate molds which is uniformly mixed and dispersed at a ratio of 0.01 to 5.0%. (20), carbon fibers dispersed into single fibers with a length of 5 to 100 mm in gypsum powder? , 0°0 for the gypsum powder
Patent i? characterized in that it is uniformly mixed and dispersed at a ratio of 1 to 1.0 weight f%. 19. The carbon-fiber-containing gypsum powder for use as a gypsum intermediate top according to item 19. (21) Cut the carbon fiber into lengths of 5 to 200 inches and create countless pieces! The carbon fibers are dispersed in advance into one magnetic fiber, and the gypsum powder and the carbon fibers, which are dispersed into single m fibers with a weight of 0.01 to 5 times 1 fk% relative to the gypsum powder, are placed in a circulating jet air stream. A method for producing carbon fiber-containing gypsum powder for a gypsum model, a model copy, or a master model, which comprises charging the powder and uniformly mixing the two, and then recovering the powder. (22) Cut the carbon fiber to a length of 5 to 200 mm and disperse it into several single fibers in advance, add gypsum powder,
A gypsum model characterized in that the gypsum powder is chopped and the carbon fibers are dispersed into single fibers having a mass of 0.01 to 5%, and the carbon fibers are put into a flexible bag and rocked and rotated. A method for producing carbon fiber-containing gypsum powder for model reproduction molds or master molds. (23), the carbon is cut into lengths of 5 to 100 RII and dispersed in advance into countless single fibers, and then mixed with gypsum powder and 0.01 to 5% by weight of single fibers with respect to the gypsum powder. A method for producing a carbon fiber-containing gypsum powder for intermediate temperature use made of gypsum, characterized in that the carbon fibers dispersed in the gypsum powder are introduced into a circulating jet air flow, and the two are uniformly mixed and then recovered. (24), carbon fibers are cut into lengths of 5 to 10 osus and dispersed in advance into countless single fibers, and then mixed with gypsum powder and single fibers with a total percentage of 0.01 to 5M relative to the gypsum powder. A method for producing carbon fiber-containing gypsum powder for an intermediate mold made of gypsum, characterized in that the dispersed carbon fibers are placed in a flexible bag and rocked and rotated. ” The above procedural amendments Numakawa January 25, 1960 (Mr. 1 Chief Adjudicator of the Japan Patent Office)
1. Indication of the case 1980 1 Blue Permit No. 203764 3. Relationship with the case by the person making the amendment 'Zet 3'r Susuke Issei 1 (Residence) 14, 756 Soi-cho, Yokkaichi City, Mie Prefecture.
Agent 〒500 Address 3Y-5, Kano Asahi-cho, Gifu City I will submit the originals of the photographs of drawings 5 and 7 of the application. Motion of amendment to the above procedure February 18, 1985 Manabu Shiga, Commissioner of the Patent Office (Chief Adjudicator of the Patent Office) (Examiner of the Patent Office) 3. Relationship with the amended person case Special 1 applicant address (Residence)
756 Ichii-cho, Yokka T1i City, Mie Prefecture. JP Ike 18, Contents of the amendment tsu It is. "Figure 5 is a photograph of the crystal structure of a gypsum sample piece using powder for β-type stone, taken with a scanning electron microscope, and Figure 7 is
This is a photograph of the crystal structure of a gypsum sample piece using α-type gypsum powder. ” he corrected. −1 above

Claims (1)

Scope of Claims: (1) Carbon fibers with a length of 5 to 200 mm are dispersed into single fibers within the gypsum structure of the base material, and the carbon fibers are 0.0% relative to the gypsum.
A carbon fiber-reinforced plaster model or model copy mold, characterized in that the carbon fiber reinforced plaster model or model copy mold is uniformly mixed and dispersed in a proportion of 0.008 to 2.0% by weight. (2) A patent claim characterized in that carbon fibers having a length of 5 to 100 mm are uniformly mixed and dispersed in the base material of plaster at a ratio of 0.008 to 0.9% by weight based on the plaster. A carbon fiber-reinforced plaster model or model reproduction mold according to item 1. (3) Carbon fibers with a length of 5 to 200 mm are dispersed into single fibers within the gypsum structure of the base material, and 0.
A carbon fiber-reinforced gypsum master mold characterized in that the carbon fiber reinforced gypsum mold is uniformly mixed and dispersed in a proportion of 0.008 to 2.0% by weight. (4) A patent claim characterized in that carbon fibers having a length of 5 to 100 mm are uniformly mixed and dispersed in the base material gypsum at a ratio of 0.008 to 0.9% by weight based on the gypsum. A carbon fiber-reinforced gypsum prototype according to scope 3. (5) A patent claim characterized in that carbon fibers having a length of 15 to 30 mm are uniformly mixed and dispersed in the base material of plaster at a ratio of 0.05 to 0.3% by weight based on the plaster. A master mold for a carbon fiber-reinforced gypsum mold according to scope 3. (6) The mold is a ceramic casting mold, a potter's wheel mold, or a paper carton casting mold made from paper pulp slurry;
The carbon fiber-reinforced gypsum mold prototype according to claims 3 to 5, which is a mold that utilizes the water absorbing properties of gypsum, such as a press mold. (7) The mold is a plastic product, a synthetic rubber product,
Claim 3, characterized in that it is a mold such as a casting mold, an extrusion mold, an injection mold, etc. for non-ferrous metal products.
A master mold for a carbon fiber-reinforced gypsum mold according to items 5 to 6. (8) The mold is a press mold or injection mold for so-called fine ceramic products that do not contain clay as raw materials;
A master mold for a carbon fiber-reinforced gypsum mold according to any one of claims 3 to 5, which is a mold such as a casting mold. (9) Carbon fibers with a length of 5 to 100 mm are dispersed into single fibers within the gypsum structure of the base material, and 0.
An intermediate mold for a mold made of carbon fiber reinforced gypsum, characterized in that carbon fiber is uniformly mixed and dispersed in a proportion of 0.08 to 0.9% by weight. (10) A patent claim that carbon fibers having a length of 15 to 30 mm are uniformly mixed and dispersed in the base material gypsum at a ratio of 0.05 to 0.3% by weight based on the gypsum. An intermediate mold for a carbon fiber-reinforced gypsum mold according to Item 9. (11) The mold is a ceramic casting mold, a potter's wheel mold, or a paper carton casting mold made from paper pulp slurry;
11. An intermediate mold for a carbon fiber-reinforced gypsum mold according to any one of claims 9 to 10, which is a mold that utilizes water absorbency of gypsum like a press mold. (12) The carbon according to claims 9 to 10, wherein the mold is a mold such as a casting mold, an extrusion mold, or an injection mold for plastic products or non-ferrous metal products. Intermediate mold for fiber-reinforced gypsum molds. (13) A patent claim characterized in that the mold is used for press molding, injection molding, casting molding, and extrusion molding of so-called fine ceramic products that do not contain clay as a raw material. An intermediate mold for a carbon fiber-reinforced gypsum mold according to item 9 or 10. (14), length 5 to 200 mm in the plaster of the base material of the mold
When the carbon fibers are dispersed into single fibers, it is 0 against the plaster.
．． A carbon fiber-reinforced plaster model characterized in that the carbon fibers are uniformly mixed and dispersed at a proportion of 0.008 to 2.0% by weight, and the surface layer of the mold is covered with plaster containing a smaller proportion of carbon fibers than other parts. Or a model copy mold. (13), length 5 to 200 mm in the plaster of the base material of the mold
When the carbon fibers are dispersed into single fibers, it is 0 against the plaster.
．． A master mold made of carbon fiber-reinforced gypsum, characterized in that the carbon fibers are uniformly mixed and dispersed at a proportion of 0.008 to 2.0% by weight, and the surface layer of the mold is covered with plaster containing a smaller proportion of carbon fibers than other parts. . (16), a length of 5 to 100 mm in the plaster of the base material of the mold.
When the carbon fibers are dispersed into single fibers, it is 0 against the plaster.
．． An intermediate for a mold made of carbon fiber-reinforced gypsum, characterized in that the carbon fiber-reinforced gypsum is uniformly mixed and dispersed in a proportion of 0.008 to 0.9% by weight, and the surface of the mold is coated with pure gypsum without carbon fibers mixed therein. Type. (17) Carbon fibers dispersed into single fibers with a length of 5 to 200 mm are added to the gypsum powder at a rate of 0.0% relative to the gypsum powder.
A gypsum powder containing carbon fiber for use in plaster models, model reproduction molds, or master molds, which is uniformly mixed and dispersed in a proportion of 0.01 to 5% by weight. (18), carbon fibers having a length of 5 to 100 mm are uniformly mixed and dispersed in the gypsum powder at a ratio of 0.01 to 1.0% by weight based on the gypsum powder. A carbon fiber-containing gypsum powder for plaster models, model copies, or originals as set forth in claim 17. (19) Carbon fibers dispersed into single fibers with a length of 5 to 100 mm are added to the gypsum powder at a rate of 0.0% relative to the gypsum powder.
A gypsum powder containing carbon fibers for intermediate molds made of gypsum, which is uniformly mixed and dispersed in a proportion of 0.01 to 5% by weight. (20), carbon fibers having a length of 5 to 100 mm are uniformly mixed and dispersed in the gypsum powder at a ratio of 0.01 to 1.0% by weight based on the gypsum powder. A carbon fiber-containing gypsum powder for a gypsum intermediate mold according to claim 19. (21), carbon fibers are cut into lengths of 5 to 200 mm and dispersed in advance into countless single fibers, and then mixed with gypsum powder and 0.01 to 5% by weight of single fibers with respect to the gypsum powder. A gypsum powder containing carbon fibers for use in plaster models, model reproduction molds, or master molds, characterized in that the dispersed carbon fibers are introduced into a circulating jet air flow to uniformly mix the two and then recovered. manufacturing method. (22), carbon fibers are cut into lengths of 5 to 200 mm and dispersed in advance into countless single fibers, and then mixed with gypsum powder and single fibers of 0.01 to 5% by weight based on the gypsum powder. A method for producing carbon fiber-containing gypsum powder for a plaster model, a model copy, or a master model, characterized in that the dispersed carbon fibers are placed in a flexible bag and rocked and rotated. (23), carbon fibers are cut into lengths of 5 to 100 mm and dispersed in advance into countless single fibers, and then mixed with gypsum powder and 0.1 to 5% by weight of single fibers with respect to the gypsum powder. A method for producing carbon fiber-containing gypsum powder for a gypsum intermediate mold, characterized in that the dispersed carbon fibers are introduced into a circulating jet air stream, uniformly mixed, and then recovered. (24), carbon fibers are cut into lengths of 5 to 100 mm and dispersed in advance into countless single fibers, and then mixed with gypsum powder and 0.01 to 5% by weight of single fibers with respect to the gypsum powder. A method for producing carbon fiber-containing gypsum powder for an intermediate mold made of gypsum, characterized in that the dispersed carbon fibers are placed in a flexible bag and rocked and rotated.