JPH01130842A - Manufacture of core for high pressure casting - Google Patents
Manufacture of core for high pressure castingInfo
- Publication number
- JPH01130842A JPH01130842A JP28814687A JP28814687A JPH01130842A JP H01130842 A JPH01130842 A JP H01130842A JP 28814687 A JP28814687 A JP 28814687A JP 28814687 A JP28814687 A JP 28814687A JP H01130842 A JPH01130842 A JP H01130842A
- Authority
- JP
- Japan
- Prior art keywords
- core
- cavity
- coating layer
- pressure casting
- mica
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000005266 casting Methods 0.000 title claims abstract description 18
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 8
- 239000004576 sand Substances 0.000 claims abstract description 19
- 239000010445 mica Substances 0.000 claims abstract description 16
- 229910052618 mica group Inorganic materials 0.000 claims abstract description 16
- 239000000463 material Substances 0.000 claims abstract description 15
- 239000002002 slurry Substances 0.000 claims abstract description 8
- 238000010438 heat treatment Methods 0.000 claims abstract description 7
- 239000011248 coating agent Substances 0.000 claims description 25
- 238000000576 coating method Methods 0.000 claims description 14
- 239000010419 fine particle Substances 0.000 claims description 11
- 239000000945 filler Substances 0.000 claims description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 24
- 239000011247 coating layer Substances 0.000 abstract description 23
- 238000000034 method Methods 0.000 abstract description 17
- 238000000465 moulding Methods 0.000 abstract description 8
- 235000019353 potassium silicate Nutrition 0.000 abstract description 5
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 abstract description 5
- 239000003795 chemical substances by application Substances 0.000 abstract description 4
- 239000000377 silicon dioxide Substances 0.000 abstract description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 abstract 1
- GBCAVSYHPPARHX-UHFFFAOYSA-M n'-cyclohexyl-n-[2-(4-methylmorpholin-4-ium-4-yl)ethyl]methanediimine;4-methylbenzenesulfonate Chemical compound CC1=CC=C(S([O-])(=O)=O)C=C1.C1CCCCC1N=C=NCC[N+]1(C)CCOCC1 GBCAVSYHPPARHX-UHFFFAOYSA-M 0.000 abstract 1
- 238000012856 packing Methods 0.000 abstract 1
- 239000011863 silicon-based powder Substances 0.000 abstract 1
- 239000002184 metal Substances 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- RJDOZRNNYVAULJ-UHFFFAOYSA-L [O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[F-].[F-].[Mg++].[Mg++].[Mg++].[Al+3].[Si+4].[Si+4].[Si+4].[K+] Chemical compound [O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[F-].[F-].[Mg++].[Mg++].[Mg++].[Al+3].[Si+4].[Si+4].[Si+4].[K+] RJDOZRNNYVAULJ-UHFFFAOYSA-L 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 238000007598 dipping method Methods 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 238000005507 spraying Methods 0.000 description 3
- 239000011230 binding agent Substances 0.000 description 2
- VKYKSIONXSXAKP-UHFFFAOYSA-N hexamethylenetetramine Chemical compound C1N(C2)CN3CN1CN2C3 VKYKSIONXSXAKP-UHFFFAOYSA-N 0.000 description 2
- 239000012466 permeate Substances 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910052845 zircon Inorganic materials 0.000 description 2
- GFQYVLUOOAAOGM-UHFFFAOYSA-N zirconium(iv) silicate Chemical compound [Zr+4].[O-][Si]([O-])([O-])[O-] GFQYVLUOOAAOGM-UHFFFAOYSA-N 0.000 description 2
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910052626 biotite Inorganic materials 0.000 description 1
- 125000002057 carboxymethyl group Chemical group [H]OC(=O)C([H])([H])[*] 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000004512 die casting Methods 0.000 description 1
- YGANSGVIUGARFR-UHFFFAOYSA-N dipotassium dioxosilane oxo(oxoalumanyloxy)alumane oxygen(2-) Chemical group [O--].[K+].[K+].O=[Si]=O.O=[Al]O[Al]=O YGANSGVIUGARFR-UHFFFAOYSA-N 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 235000010299 hexamethylene tetramine Nutrition 0.000 description 1
- 239000004312 hexamethylene tetramine Substances 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 239000011268 mixed slurry Substances 0.000 description 1
- 229910052627 muscovite Inorganic materials 0.000 description 1
- 229920003986 novolac Polymers 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 229920001568 phenolic resin Polymers 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229910052628 phlogopite Inorganic materials 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 229920002379 silicone rubber Polymers 0.000 description 1
- 239000004945 silicone rubber Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
Landscapes
- Molds, Cores, And Manufacturing Methods Thereof (AREA)
- Casting Devices For Molds (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の目的〕
（産業上の利用分野）
この発明は、ダイカスト法などの高圧鋳造用中子の製造
方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method for producing a core for high pressure casting such as a die casting method.
（従来の技術）
模型のキャビティに充填した充填砂に高周波を照射し、
充填砂を加熱硬化させて造型する方法は、たとえば特開
昭５７−１５６８６０号公報、特開昭６１−７１１５２
号公報等で知られている。(Conventional technology) High frequency waves are irradiated to the sand filled in the cavity of the model.
Methods of molding by heating and hardening the filled sand are disclosed, for example, in JP-A-57-156860 and JP-A-61-71152.
It is known from the publication No.
これらの造型方法は、模型のキャピテイ内面に水ガラス
などの液状塗型剤を霧状に吹付けて塗膜を形成し、つぎ
に塗膜を形成したキャビティ内に流動性のある充填砂を
充填する。そして、このキャビティ内の充填砂に高周波
を照射して充填砂を加熱硬化させて中子を造型する方法
である。These molding methods involve spraying a liquid coating agent such as water glass as a mist onto the inner surface of the model cavity to form a coating film, and then filling the cavity with the coating film with fluid filling sand. do. Then, the filling sand in the cavity is irradiated with high frequency waves to heat and harden the filling sand, thereby molding the core.
この方法によれば、充填砂に流動砂を使用し、しかも塗
型剤に無機質のバインダを使用しているため、鋳肌の平
滑な鋳物が製造されるが、高圧鋳造用として開発された
ものではない。したがって、前記方法で得られた中子を
高圧鋳造に用いた場合、１００＃／ｒｉ程度の加圧力で
塗型剤層へ溶湯が浸透してしまうという問題がある。According to this method, since fluidized sand is used as the filling sand and an inorganic binder is used as the coating agent, castings with smooth casting surfaces are manufactured, but this method was developed for high-pressure casting. isn't it. Therefore, when the core obtained by the above method is used for high-pressure casting, there is a problem that the molten metal permeates into the mold coating layer under a pressure of about 100 #/ri.
一方、高圧鋳造用中子の製造方法としては、たとえば特
開昭５６−１３９２５６＠公報、特開昭５８−１２８２
４５号公報等が知られている。この方法は、有機バイン
ダを用いて砂中子を造型し、この砂中子表面に粉末状の
耐火物と水溶性熱硬化樹脂とを混合したアルカリ性水溶
液からなるスラリーを塗布し、これを乾燥して第１コー
ティング層を形成し、さらにこの第１コーティング層の
表面に合成雲母を含む溶液を塗布し、これを乾燥して第
２コーティング層を形成した方法である。On the other hand, methods for manufacturing cores for high-pressure casting include, for example, JP-A-56-139256@publication and JP-A-58-1282.
Publication No. 45 and the like are known. This method involves molding a sand core using an organic binder, applying a slurry consisting of an alkaline aqueous solution containing a powdered refractory and a water-soluble thermosetting resin to the surface of the sand core, and drying this. In this method, a first coating layer was formed using the first coating layer, and then a solution containing synthetic mica was applied to the surface of the first coating layer, and this was dried to form a second coating layer.
この方法によれば、耐圧性に優れた中子を造型でき、ま
た表面は合成雲母を含む溶液でコーティングされている
ために、中子の表面にクラックあるいは空孔が形成され
ないが、２回のコーティング作業が必要となる。According to this method, it is possible to mold a core with excellent pressure resistance, and since the surface is coated with a solution containing synthetic mica, no cracks or holes are formed on the surface of the core, but it is possible to mold a core with excellent pressure resistance. Coating work is required.
（発明が解決しようとする問題点）
萌述したように、従来の造型方法の前者の方法は、中子
を高圧鋳造に用いた場合に加圧力で塗型剤層へ溶湯が浸
透してしまうという問題があり、また後者の方法は、２
回のコーティング作業が必要となり、作業が繁雑となる
。(Problems to be Solved by the Invention) As mentioned above, in the former method of conventional molding methods, when the core is used for high-pressure casting, the molten metal permeates into the mold coating layer due to the pressure applied. There is a problem with this, and the latter method requires 2
This requires multiple coating operations, making the work complicated.
この発明は、前記事情に着目してなされたもので、その
目的とするところは、耐圧性に優れた中子を容易に製造
できる高圧鋳造用中子の製造方法を提供することにある
。The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a method for manufacturing a core for high-pressure casting that can easily produce a core with excellent pressure resistance.
（問題点を解決づるための手段及び作用）この発明は、
模型のキャビティ内面に微粒子を含有した塗型剤を塗布
して塗膜を形成し、つぎにこのキャビティ内に充填砂を
充填しこれを高周波加熱して硬化させ、表面に微粒子が
コーティングされた基中子を形成する。さらにこの基中
子の表面に雲母系物質または鱗片状物質のスラリーをコ
ーティングしてコーティング層を形成する。そして、中
子の表面に塗型剤に含有している微粒子層を介して雲母
系物質または鱗片状物質からなるコーティング層を形成
したことにある。(Means and effects for solving the problem) This invention has the following features:
A coating agent containing fine particles is applied to the inner surface of the model cavity to form a coating film, and then filler sand is filled into the cavity and hardened by high frequency heating to form a base coated with fine particles on the surface. Form the core. Furthermore, a slurry of a mica-based material or a scaly material is coated on the surface of this base core to form a coating layer. A coating layer made of a mica-based material or a scaly material is formed on the surface of the core via a layer of fine particles contained in a mold coating agent.
（実施例）
以下、この発明の一実施例を図面にもとづいて説明する
。(Example) Hereinafter, an example of the present invention will be described based on the drawings.
第１図（ａ）〜（ｆ）は高圧鋳造用中子を製造する工程
を示すもので、１は耐熱性に優れたシリコンゴム等の樹
脂材料によって成形された模型であり、２はキャピテイ
である。まず、（ａ）に示すようにキャビティ２に塗型
剤３を流し込み、その内面に塗を剤３を一様に付着し、
余分な塗型剤３は（１））に示すように排出する。ここ
で使用する塗型剤３は、微粒子として１μｍジルコンパ
ウダー５０部、１０部ｍジルコンパウダー５０部に、１
９６０ＭＣ（カルボキシメチル
溶液４０部と水ガラス１部を添加して良く攪拌した水溶
液であり、キャビティ２の内面に微粒子を含有した塗１
１１４が形成される。つぎに、（Ｃ）に示すように塗膜
４が形成されたキャビティ２に充填砂５を充填するが、
この充填砂５は、フラタリー珪砂１００部に水ガラス３
部を添加し、５分間混練しながら５０°Ｃの温風で乾燥
した混練砂であり、キャビティ２に密に充填したのち、
（ｄ）に示すように高周波加熱炉６の内部に模型１を収
納する。そして、４ｋＷの高周波を１分間照射すると、
充填砂５は加熱硬化され、（ｅ）に示すような基中子７
が造型される。造型後、模型１から基中子７を取出す。Figures 1 (a) to (f) show the process of manufacturing cores for high-pressure casting, in which 1 is a model molded from a resin material such as silicone rubber with excellent heat resistance, and 2 is a cavity. be. First, as shown in (a), the coating agent 3 is poured into the cavity 2, and the coating agent 3 is uniformly attached to the inner surface of the cavity 2.
Excess mold coating agent 3 is discharged as shown in (1)). The coating agent 3 used here consists of 50 parts of 1 μm zircon powder, 50 parts of 1 μm zircon powder, and 1 μm as fine particles.
960MC (an aqueous solution prepared by adding 40 parts of carboxymethyl solution and 1 part of water glass and stirring well, coating 1 containing fine particles on the inner surface of cavity 2)
114 is formed. Next, as shown in (C), the cavity 2 in which the coating film 4 has been formed is filled with filler sand 5.
This filling sand 5 is composed of 100 parts of flattary silica sand and 3 parts of water glass.
This is a mixed sand that is dried with warm air at 50°C while kneading for 5 minutes, and after densely filling cavity 2,
As shown in (d), the model 1 is housed inside the high-frequency heating furnace 6. Then, when irradiated with 4kW high frequency for 1 minute,
The filling sand 5 is heated and hardened to form a base core 7 as shown in (e).
is molded. After molding, the base core 7 is taken out from the model 1.
この基中子７の表面には前記キャビティ２の内面に形成
した塗膜４、つまり微粒子を含有した塗型剤３のコーテ
ィング層８が形成される。A coating film 4 formed on the inner surface of the cavity 2, that is, a coating layer 8 of the mold coating agent 3 containing fine particles is formed on the surface of the base core 7.
つぎに、前記基中子７の表面に（ｅ）に示すようにスラ
リー９を塗布するが、このスラリー９は、２％ＣＭＣ水
溶液１００部、２００メツシユ以下の天然雲母３０部、
界面活性剤０．２部の混合スラリー液であり、このスラ
リー９に前記基中子７を１秒間浸漬して基中子７の表面
に雲母コーティング層１０を形成する。表面に雲母コー
ティング層１０を形成した基中子７を（ｆ）に示すよう
に加熱炉１１に入れ、１１０°Ｃで１時間乾燥すると、
雲母コーティング層１０は加熱硬化され、基中子７の表
面に微粒子を含有した塗型剤３からなる塗膜４を介して
雲母コーティング層１０が形成される。したがって、第
２図に拡大して示すように基中子７の表面には充填砂５
に一部侵入した微粒子を含んだコーティング層８および
その外側に雲母コーティング層１０が被覆される。Next, a slurry 9 is applied to the surface of the base core 7 as shown in (e), and this slurry 9 consists of 100 parts of a 2% CMC aqueous solution, 30 parts of natural mica of 200 mesh or less,
The base core 7 is immersed in this slurry 9 for 1 second to form a mica coating layer 10 on the surface of the base core 7 . The base core 7 with the mica coating layer 10 formed on the surface is placed in a heating furnace 11 as shown in (f) and dried at 110°C for 1 hour.
The mica coating layer 10 is heated and cured, and the mica coating layer 10 is formed on the surface of the base core 7 via the coating film 4 made of the coating agent 3 containing fine particles. Therefore, as shown in an enlarged view in FIG. 2, the surface of the base core 7 is filled with sand.
A coating layer 8 containing fine particles partially penetrated into the coating layer 8 and a mica coating layer 10 are coated on the outside thereof.
以上の方法で製造された高圧鋳造用中子を金型にセット
し、加圧力５００８９／ｃｄ，’Ｓ口速度０、９ＴｒＬ
／Ｓｅｃ、溶ｍＷ度７００’ Ｃの条件下で加圧鋳造し
た。この結果、中子折れは皆無で、中子の表面が雲母コ
ーティング層によって平滑であるため中子砂は振動のみ
で１００％落ちた。The high-pressure casting core manufactured by the above method was set in a mold, and the pressing force was 50089/cd, 'S mouth speed was 0, and 9TrL.
Pressure casting was carried out under conditions of /Sec, melt mW degree of 700'C. As a result, there was no core breakage, and since the surface of the core was smooth due to the mica coating layer, 100% of the core sand fell off due to vibration alone.
なお、前記一実施例における雲母物質は、白雲母、金雲
母、黒雲母、合成雲母等を用い、塗布方法としては浸漬
法に限定されず、スプレー塗布、へヶ塗り法でもよい。The mica material used in the above embodiment is muscovite, phlogopite, biotite, synthetic mica, etc., and the coating method is not limited to the dipping method, but may also be a spray coating method or a dipping method.
また、前記一実施例においては、雲母物質のスラリーを
コーティングしたが、雲母物質に限定されず、つぎに示
す鱗片状物質（金属薄片）をコーティングしてもよい。Further, in the above embodiment, the slurry of mica material was coated, but the coating is not limited to mica material, and the following scaly material (metal flakes) may be coated.
メチールアルコール １００部鱗片状ステン
レス １０部鱗片状黒鉛
３０部ノボラックフェノール樹脂 ２
部へキサメチレンテトラミン ０．３部の混合スラ
リー液に基中子を１分間浸漬するか、前述したようにス
プレー塗布、へヶ塗り等によってコーティング層を形成
する。Methyl alcohol 100 parts Scaly stainless steel 10 parts Scaly graphite
30 parts novolak phenolic resin 2
A coating layer is formed by immersing the base core in a mixed slurry containing 0.3 parts of hexamethylenetetramine for 1 minute, or by spray coating, dipping, etc. as described above.
以上説明したように、この発明によれば、表面に微粒子
を含有する塗型剤がコーティングされた基中子の表面に
雲母系物質または鱗片状物質のコーティング層を形成す
ることによって、従来のように２回のコーティング作業
を行なうことなく、高圧鋳造に耐えられる中子を製造で
きる。また、鋳造時の加圧力で溶湯が中子の表面に浸透
することはなく、平滑な鋳肌となるという効果がある。As explained above, according to the present invention, a coating layer of a mica-based substance or a scale-like substance is formed on the surface of a base core coated with a molding agent containing fine particles, unlike the conventional method. Cores that can withstand high-pressure casting can be manufactured without having to perform two coating operations. In addition, the molten metal does not penetrate the surface of the core due to the pressure applied during casting, resulting in a smooth casting surface.
第１図（ａ）〜（ｆ）はこの発明の製造方法の一実施例
を示す説明図、第２図は中子の一部を拡大した断面図で
ある。
１・・・模型、２・・・キャビティ、３・・・塗型剤、
４・・・塗膜、５・・・充填砂、７・・・基中子、１０
・・・コーティング層。
出願人代理人 弁理士 鈴江武彦FIGS. 1(a) to 1(f) are explanatory views showing one embodiment of the manufacturing method of the present invention, and FIG. 2 is an enlarged sectional view of a part of the core. 1... Model, 2... Cavity, 3... Coating agent,
4... Paint film, 5... Filling sand, 7... Base core, 10
...Coating layer. Applicant's agent Patent attorney Takehiko Suzue
Claims (1)
して塗膜を形成する第１の工程と、前記キャビティ内に
充填砂を充填しこれを高周波加熱して硬化させ、表面に
微粒子がコーティングされた基中子を形成する第２の工
程と、前記基中子の表面に雲母系物質または鱗片状物質
のスラリーをコーティングする第３の工程とからなる高
圧鋳造用中子の製造方法。The first step is to apply a coating agent containing fine particles to the inner surface of the model cavity to form a coating film, and fill the cavity with filler sand and harden it by high-frequency heating to coat the surface with fine particles. A method for producing a high-pressure casting core, comprising: a second step of forming a base core, and a third step of coating the surface of the base core with a slurry of a mica-based material or a scaly material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28814687A JPH01130842A (en) | 1987-11-13 | 1987-11-13 | Manufacture of core for high pressure casting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28814687A JPH01130842A (en) | 1987-11-13 | 1987-11-13 | Manufacture of core for high pressure casting |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01130842A true JPH01130842A (en) | 1989-05-23 |
Family
ID=17726400
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP28814687A Pending JPH01130842A (en) | 1987-11-13 | 1987-11-13 | Manufacture of core for high pressure casting |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01130842A (en) |
-
1987
- 1987-11-13 JP JP28814687A patent/JPH01130842A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR900001344B1 (en) | Making method for the casting mold | |
| EP0060731A2 (en) | Pattern for producing a mould and method for manufacture of such a pattern | |
| US2703913A (en) | Precision casting | |
| CN108115093A (en) | A kind of gypsum shell full form casting process based on composite sand mould loam core | |
| JPH01130842A (en) | Manufacture of core for high pressure casting | |
| JP2524761B2 (en) | Method for producing collapsible core | |
| JPS6236779B2 (en) | ||
| JPH01130845A (en) | Manufacture of core for high pressure casting | |
| JPH01215433A (en) | Manufacture of core for high pressure casting | |
| JPH01130844A (en) | Manufacture of core for high pressure casting | |
| JP3629640B2 (en) | Method for producing collapsible sand core for casting and sand core thereof | |
| JP2568402B2 (en) | Method for producing collapsible core | |
| JPS6358082B2 (en) | ||
| JPH01130843A (en) | Manufacture of core for high pressure casting | |
| JPS61137646A (en) | Manufacture of casting mold | |
| JP3121222B2 (en) | How to make a dental mold | |
| JPS6146347A (en) | Production of casting mold | |
| JPH01197041A (en) | Method for molding mold | |
| JPH0118819B2 (en) | ||
| JPS62259637A (en) | Molding method for casting mold | |
| JPH0147267B2 (en) | ||
| JPS612507A (en) | Porous durable mold and manufacture thereof | |
| JPH0775758B2 (en) | Mold making method using microwave heating | |
| SU1281337A1 (en) | Method of producing moulds by vacuum moulding | |
| JPS6233017B2 (en) |