JPH0477352A - Binder composition for molding ceramic - Google Patents
Binder composition for molding ceramicInfo
- Publication number
- JPH0477352A JPH0477352A JP2191030A JP19103090A JPH0477352A JP H0477352 A JPH0477352 A JP H0477352A JP 2191030 A JP2191030 A JP 2191030A JP 19103090 A JP19103090 A JP 19103090A JP H0477352 A JPH0477352 A JP H0477352A
- Authority
- JP
- Japan
- Prior art keywords
- binder
- starch granules
- mold
- solvent
- molded body
- 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
- 239000011230 binding agent Substances 0.000 title claims abstract description 47
- 239000000919 ceramic Substances 0.000 title claims abstract description 34
- 238000000465 moulding Methods 0.000 title claims abstract description 10
- 239000000203 mixture Substances 0.000 title claims description 20
- 229920002472 Starch Polymers 0.000 claims abstract description 39
- 239000008107 starch Substances 0.000 claims abstract description 39
- 235000019698 starch Nutrition 0.000 claims abstract description 39
- 239000008187 granular material Substances 0.000 claims abstract description 32
- 239000000843 powder Substances 0.000 claims abstract description 27
- 239000002904 solvent Substances 0.000 claims abstract description 19
- 238000001035 drying Methods 0.000 abstract description 11
- 229920000945 Amylopectin Polymers 0.000 abstract description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 6
- 244000061456 Solanum tuberosum Species 0.000 abstract description 3
- 235000002595 Solanum tuberosum Nutrition 0.000 abstract description 3
- 235000012015 potatoes Nutrition 0.000 abstract description 3
- 244000017020 Ipomoea batatas Species 0.000 abstract description 2
- 235000002678 Ipomoea batatas Nutrition 0.000 abstract description 2
- 240000008042 Zea mays Species 0.000 abstract description 2
- 235000005824 Zea mays ssp. parviglumis Nutrition 0.000 abstract description 2
- 235000002017 Zea mays subsp mays Nutrition 0.000 abstract description 2
- 235000013339 cereals Nutrition 0.000 abstract description 2
- 235000005822 corn Nutrition 0.000 abstract description 2
- 230000001105 regulatory effect Effects 0.000 abstract 1
- 239000002002 slurry Substances 0.000 description 23
- 239000000047 product Substances 0.000 description 14
- 229920000856 Amylose Polymers 0.000 description 12
- 238000005238 degreasing Methods 0.000 description 9
- 238000000034 method Methods 0.000 description 8
- 238000002156 mixing Methods 0.000 description 8
- 238000010438 heat treatment Methods 0.000 description 7
- 238000005336 cracking Methods 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 238000005245 sintering Methods 0.000 description 3
- 229920001353 Dextrin Polymers 0.000 description 2
- 239000004375 Dextrin Substances 0.000 description 2
- 150000001298 alcohols Chemical class 0.000 description 2
- 230000037237 body shape Effects 0.000 description 2
- 235000019425 dextrin Nutrition 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000499 gel Substances 0.000 description 2
- 229920000609 methyl cellulose Polymers 0.000 description 2
- 239000001923 methylcellulose Substances 0.000 description 2
- 235000010981 methylcellulose Nutrition 0.000 description 2
- 229920001169 thermoplastic Polymers 0.000 description 2
- 229920001187 thermosetting polymer Polymers 0.000 description 2
- 239000004416 thermosoftening plastic Substances 0.000 description 2
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 1
- 108010010803 Gelatin Proteins 0.000 description 1
- 239000004354 Hydroxyethyl cellulose Substances 0.000 description 1
- 229920000663 Hydroxyethyl cellulose Polymers 0.000 description 1
- 208000025174 PANDAS Diseases 0.000 description 1
- 208000021155 Paediatric autoimmune neuropsychiatric disorders associated with streptococcal infection Diseases 0.000 description 1
- 240000000220 Panda oleosa Species 0.000 description 1
- 235000016496 Panda oleosa Nutrition 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 235000021355 Stearic acid Nutrition 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 150000001408 amides Chemical class 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 1
- 239000004359 castor oil Substances 0.000 description 1
- 235000019438 castor oil Nutrition 0.000 description 1
- 229920002301 cellulose acetate Polymers 0.000 description 1
- 229920006184 cellulose methylcellulose Polymers 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 229920000159 gelatin Polymers 0.000 description 1
- 239000008273 gelatin Substances 0.000 description 1
- 235000019322 gelatine Nutrition 0.000 description 1
- 235000011852 gelatine desserts Nutrition 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- ZEMPKEQAKRGZGQ-XOQCFJPHSA-N glycerol triricinoleate Natural products CCCCCC[C@@H](O)CC=CCCCCCCCC(=O)OC[C@@H](COC(=O)CCCCCCCC=CC[C@@H](O)CCCCCC)OC(=O)CCCCCCCC=CC[C@H](O)CCCCCC ZEMPKEQAKRGZGQ-XOQCFJPHSA-N 0.000 description 1
- 235000019447 hydroxyethyl cellulose Nutrition 0.000 description 1
- 150000002576 ketones Chemical class 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 1
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 239000012188 paraffin wax Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920002037 poly(vinyl butyral) polymer Polymers 0.000 description 1
- 229920000058 polyacrylate Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229920000193 polymethacrylate Polymers 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 239000008117 stearic acid Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 239000001993 wax Substances 0.000 description 1
Landscapes
- Compositions Of Oxide Ceramics (AREA)
Abstract
Description
【発明の詳細な説明】
[産業上の利用分野]
本発明は、セラミックス粉末より成形体を形成する際に
使用されるバインダー組成物に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a binder composition used in forming a molded body from ceramic powder.
[従来の技術]
従来、複雑形状のセラミックス製品を成形する場合は、
セラミックス粉末に高分子またはワックスなどの熱可塑
性物質および溶媒をバインダーとして混合して型内に注
入する方法があり実用化されている。ところで、この型
内で成形され脱型された成形体は溶媒を含んでおり乾燥
により除去される。この乾燥脱脂時の加熱により有機バ
インダーは熱可塑性であるので熱で軟化して結合力が低
下しやすい。このため成形体は結合力が不十分で脆くな
り、溶媒の除去、脱脂の際に成形体が変形したり、割れ
が発生したりする。また成形体の結合力が不十分である
と脱型時に型面にセラミックス粉末が張付いて、かけヤ
剥離がおきやすくなる。[Conventional technology] Conventionally, when molding ceramic products with complex shapes,
A method has been put into practical use in which ceramic powder is mixed with a thermoplastic substance such as a polymer or wax, and a solvent as a binder, and the mixture is injected into a mold. By the way, the molded article molded in this mold and demolded contains a solvent, which is removed by drying. Since the organic binder is thermoplastic, it is likely to be softened by the heat during this drying and degreasing process, resulting in a decrease in bonding strength. As a result, the molded product has insufficient bonding strength and becomes brittle, resulting in deformation and cracking of the molded product during removal of the solvent and degreasing. Furthermore, if the bonding strength of the molded body is insufficient, ceramic powder will stick to the mold surface during demolding, making it easy to peel off the mold.
そこで、成形体の結合力を増すために、添加する結合剤
の量を多くすることが考えられるが、この方法ではスラ
リーの粘度が上昇し型内への注入が困難となる。さらに
成形体中のセラミックス粉末の体積率が減少し、加熱に
より結合剤が軟化して変形したり、脱脂に時間がかかる
ことになり生産性が低下して好ましくない。Therefore, in order to increase the bonding strength of the molded body, it may be considered to increase the amount of binder added, but this method increases the viscosity of the slurry, making it difficult to inject it into the mold. Furthermore, the volume fraction of the ceramic powder in the molded body decreases, the binder softens and deforms due to heating, and degreasing takes time, which is undesirable as productivity decreases.
これらの点を解消するバインダーとして特開昭55−2
7887号公報には、高級アルコール類にひまし油を添
加したバインダーでセラミックス粉末を成形する旨の開
示がある。また、特開昭57−82170号公報には、
デキストリンもしくは可溶性澱粉、メチルセルロースま
たはヒドロキシセルロースからなるバインダーの開示が
ある。JP-A-55-2 is a binder that solves these problems.
Publication No. 7887 discloses that ceramic powder is molded using a binder in which castor oil is added to higher alcohols. Also, in Japanese Patent Application Laid-open No. 57-82170,
There is disclosure of binders consisting of dextrin or soluble starch, methylcellulose or hydroxycellulose.
しかしこれらのバインダーはまだ結合力などが不十分で
乾燥、脱脂時に成形体が変形したり、割れ、かけが発生
したりする問題を有している。However, these binders still have insufficient bonding strength, resulting in problems such as deformation, cracking, and chipping of molded products during drying and degreasing.
[発明が解決しようとする課題]
本発明は上記の事情に鑑みてなされたもので、型内で形
成され溶媒を含んだ成形体が脱型後の乾燥時にバインダ
ーが軟化して成形体が変形するのを防ぐことが可能なセ
ラミックス成形用バインダを提供することを目的とする
。[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned circumstances, and the present invention has been made in view of the above-mentioned circumstances.When a molded object formed in a mold and containing a solvent is dried after being removed from the mold, the binder softens and the molded object becomes deformed. It is an object of the present invention to provide a binder for ceramic molding that can prevent this from occurring.
[課題を解決するための手段]
本発明のセラミックス成形用バインダー組成物は、セラ
ミックス粉末に混合され型内に注入後固化して成形体の
形状を保持するバインダー組成物であって、溶媒と、有
機バインダーと、澱粉粒とからなることを特徴とする。[Means for Solving the Problems] The binder composition for ceramic molding of the present invention is a binder composition that is mixed with ceramic powder and solidified after being injected into a mold to maintain the shape of a molded object, and comprises a solvent, It is characterized by consisting of an organic binder and starch granules.
この溶媒としては、澱粉粒を分散し有機バインダーを溶
解ないしは分散できるものであれば利用可能である。た
とえば水、ケトン類、エステル類、アミド類、アルコー
ル類などの溶媒が利用できる。Any solvent can be used as long as it can disperse starch granules and dissolve or disperse the organic binder. For example, solvents such as water, ketones, esters, amides, and alcohols can be used.
またこの溶媒は2種以上混合して用いることもできる。Moreover, two or more kinds of these solvents can be used in combination.
有機バインダーとしては、セルロースアセテト、ポリア
クリレート、ポリメタクリレート、ポリビニルアルコー
ル、ポリビニルブチラール、デキストリン、メチルセル
ロース、ヒドロキシエチルセルロース、CMC、ゼラチ
ン、硬化油などが使用できる。これらは2種以上混合し
て用いることができる。As the organic binder, cellulose acetate, polyacrylate, polymethacrylate, polyvinyl alcohol, polyvinyl butyral, dextrin, methyl cellulose, hydroxyethyl cellulose, CMC, gelatin, hardened oil, etc. can be used. These can be used in combination of two or more types.
澱粉粒としては、ジャガイモ、さつまいも、とうもろこ
し、穀類などから採取され、表面にアミロペクチンの皮
膜を有し水に不溶のものである。Starch granules are collected from potatoes, sweet potatoes, corn, grains, etc., and have an amylopectin coating on the surface and are insoluble in water.
そして所定の温度以上に加熱することにより澱粉粒より
アミロースが溶出してアミロペクチンと共に糊状となり
結合力を示す。一方可溶性澱粉は、澱粉粒を処理して低
分子量に分解して溶解性を付与したものである。したが
って、分子量が小さく結合力が小さく成形体形状を保持
することが困難である。また可溶性であるのでこれが添
加されるとスラリー中で溶解して、粘度の高いスラリー
となり取扱が困難となる。一方この澱粉粒は、皮膜で覆
われておりスラリーは低粘度液であり、所定の温度以上
に加熱することにより始めて、アミロスを溶出させてス
ラリーの粘度を上昇させ糊化するものである。したがっ
て、この澱粉粒と有機バインダーと共にセラミックス粉
末を固化させて成形体形状を形成することができる。By heating to a predetermined temperature or higher, amylose is eluted from the starch granules and forms a paste together with amylopectin, exhibiting binding strength. On the other hand, soluble starch is obtained by processing starch granules to break down into low molecular weight particles and impart solubility to them. Therefore, the molecular weight is small and the bonding force is small, making it difficult to maintain the shape of the molded product. Furthermore, since it is soluble, when it is added, it dissolves in the slurry, resulting in a highly viscous slurry that is difficult to handle. On the other hand, the starch granules are covered with a film and the slurry is a low viscosity liquid, and only by heating it above a predetermined temperature will the amylose be eluted, increasing the viscosity of the slurry and gelatinizing it. Therefore, the ceramic powder can be solidified together with the starch granules and the organic binder to form a molded body shape.
この澱粉粒はそのまま添加してスラリーとするか、溶媒
に分散して添加してもよい。The starch granules may be added as is to form a slurry, or may be added after being dispersed in a solvent.
この成形法に使用できるセラミックス粉末としては、通
常セラミックス粉末の成形体として成形に使用されてい
るものであればいずれも適用でき、さらに焼結助剤など
を含んでいてもよい。As the ceramic powder that can be used in this molding method, any ceramic powder that is normally used for molding as a molded body of ceramic powder can be used, and may further contain a sintering aid.
このセラミックス粉末とバインダー組成物との混合物に
は、必要とあれば他の成形用の添加物を配合することも
できる。If necessary, other molding additives can be added to the mixture of the ceramic powder and the binder composition.
バインダー組成物中の澱粉粒の含有量は、10〜40容
量%とするのが好ましい。澱粉粒の量が10容量%未満
であると添加効果が認められず乾燥時の成形体の変形を
抑制することが困難となり好ましくない。また添加量が
40@1%を超えるとセラミックス粉末との混合物のス
ラリー粘度か高くなりすぎ、低圧で型への注入か困難と
なるので好ましくない。The content of starch granules in the binder composition is preferably 10 to 40% by volume. If the amount of starch granules is less than 10% by volume, no effect of the addition will be observed and it will be difficult to suppress deformation of the molded product during drying, which is not preferred. Moreover, if the amount added exceeds 40@1%, the viscosity of the slurry of the mixture with the ceramic powder becomes too high, making it difficult to pour into a mold at low pressure, which is not preferable.
このバインダー組成物は、全配合系(バインダ十セラミ
ックス粉末)に対して40〜55容量%の範囲で配合す
るのが好ましい。パンダー組成物の配合量が40容量%
未満ではセラミックス粉末をスラリー化して成形するこ
とができず好ましくない。また配合量が55容量%を超
えると成形体からの脱脂除去に時間がかかるので好まし
くない。This binder composition is preferably blended in an amount of 40 to 55% by volume based on the entire blended system (binder/ceramic powder). The amount of panda composition is 40% by volume
If it is less than that, the ceramic powder cannot be slurried and molded, which is not preferable. Moreover, if the blending amount exceeds 55% by volume, it is not preferable because it takes time to degrease the molded product.
このバインダー組成物は、澱粉粒中のアミロスか溶出し
ない温度でセラミックス粉末に混合されてスラリーを形
成する。このスラリーの調整は、たとえば、50’C以
下の温度でおこなうのが好ましい。またスラリー形成時
の機械的混合により澱粉粒中のアミロースか溶出しない
ようにすることが必要で、たとえばプロペラ式の攪拌が
好ましい。This binder composition is mixed with the ceramic powder to form a slurry at a temperature that does not dissolve the amylose in the starch granules. Preferably, the slurry is prepared at a temperature of, for example, 50'C or lower. Further, it is necessary to prevent the amylose in the starch granules from being eluted by mechanical mixing during slurry formation, and propeller-type stirring, for example, is preferable.
形成されたスラリーは、型内に注入されアミロペクチン
よりアミロースが溶出する温度、たとえば、60℃以上
に加熱されるとアミロースが溶出してアミロペクチと共
に溶液の粘度が上昇してゲル化する。そして有機バイン
ダーと共にセラミックス粉末を強固に結合して成形体形
状に固化する。The formed slurry is poured into a mold and heated to a temperature at which amylose is eluted from amylopectin, for example, 60° C. or higher, so that amylose is eluted and the viscosity of the solution increases together with amylopectin to form a gel. Then, the ceramic powder is firmly bound together with an organic binder and solidified into a molded body shape.
固化した成形体形状物は脱型されて成形体となる。The solidified molded object is demolded and becomes a molded object.
この脱型時にバインダーの澱粉が糊化して強い結合力を
有するで、セラミックス粉末が型に付着ないし張付いて
いることによる割れ、がけなどの発生を防ぐことができ
る。At the time of demolding, the starch in the binder gelatinizes and has a strong bonding force, which prevents cracking, flaking, etc. caused by the ceramic powder adhering to or sticking to the mold.
次いで、成形体は乾燥により水などの媒体が除去される
。この時澱粉粒か糊化してセラミックス粉末を強固に結
合しているので、溶媒の除去の際に成形体が変形するこ
とはない。Next, the molded body is dried to remove the medium such as water. At this time, the starch granules are gelatinized to firmly bind the ceramic powder, so the molded body will not be deformed when the solvent is removed.
ざらに乾燥された成形体は、脱脂のために加熱されるが
、この際にも熱硬化性の澱粉粒の糊がセラミックス粉末
を強固に結合しているので熱により成形体が変形したり
破損することがない。このため、焼結後も所定の形状を
保持した焼結体とすることができる。The roughly dried molded body is heated for degreasing, but at this time, the thermosetting starch granule glue firmly binds the ceramic powder, so the heat does not cause the molded body to deform or break. There's nothing to do. Therefore, the sintered body can maintain a predetermined shape even after sintering.
したがって、従来の有機バインダーのように乾燥、脱脂
工程での加熱によりバインダーが軟化して結合力が低下
して成形体が変形したり、割れたりすることがない。Therefore, unlike conventional organic binders, the binder is not softened by heating during the drying and degreasing process, resulting in a decrease in bonding strength and the molded body becoming deformed or cracked.
[作用]
本発明のバインダー組成物は、溶媒と澱粉粒および有機
バインダーとからなる。このバインダー組成物とセラミ
ックス粉末とで形成されたスラリは、流動性をもち容易
に型内への注入が可能である。このスラリーは型内に注
入されて澱粉粒よりアミロースが溶出する温度以上に加
熱される。[Function] The binder composition of the present invention consists of a solvent, starch granules, and an organic binder. The slurry formed from this binder composition and ceramic powder has fluidity and can be easily poured into a mold. This slurry is poured into a mold and heated to a temperature above which the amylose is eluted from the starch granules.
するとこのスラリーは、澱粉粒のアミロースとアミロペ
クチンにより糊化して有機バインダーと溶媒と共にゲル
化して成形体形状を保持した固化物が形成される。Then, this slurry is gelatinized by the amylose and amylopectin of the starch granules and gelled together with the organic binder and solvent to form a solidified product that maintains the shape of the molded product.
この固化した成形体は脱型されて、乾燥、脱脂される。This solidified molded body is demolded, dried, and degreased.
この時澱粉が糊化して熱硬化性の強い結合力で成形体を
維持しており、有機バインダーの結合力を補って成形体
の形状を保持することができる。したがってこの成形体
は変形、割れ、かけなどの発生が抑制できる。At this time, the starch gelatinizes and maintains the molded body with a strong thermosetting bonding force, which can supplement the binding force of the organic binder and maintain the shape of the molded body. Therefore, this molded body can be prevented from deforming, cracking, chipping, etc.
また脱型された成形体は、溶媒が存在しても澱粉が糊化
して結合されているので取扱いが容易にである。ざらに
セラミックス粉末か強固に結合しているので型面よりの
脱型も容易にできる。Further, the demolded molded product is easy to handle because the starch is gelatinized and bonded even in the presence of a solvent. Since it is strongly bonded with ceramic powder, it can be easily removed from the mold surface.
[実施例] 以下、実施例により具体的に説明する。[Example] Hereinafter, this will be explained in detail using examples.
(実施例)
窒化珪素粉末に焼結助剤のイツトリアとアルミナとをそ
れぞれ4重量%添加して湿式混合法で充分混合した後、
乾燥してセラミックス粉末とした。(Example) After adding 4% by weight of each of ittria and alumina as sintering aids to silicon nitride powder and thoroughly mixing them using a wet mixing method,
It was dried and made into ceramic powder.
このセラミックス粉末60容量%を第1図に示す混合槽
1に入れ、溶媒の水20容量%、有機バインダーとして
、パラフィンワックス10.容量%、ステアリン酸5容
量%、澱粉粒としてはジャガイモから採取した澱粉粒5
容量%を加え50℃の温度に混合槽1を保ち攪拌機5で
攪拌混合してスラリーを作成した。60% by volume of this ceramic powder was placed in a mixing tank 1 shown in FIG. 1, and 20% by volume of water as a solvent and 10% of paraffin wax as an organic binder were added. % by volume, stearic acid 5% by volume, starch granules collected from potatoes 5
% by volume was added, the mixing tank 1 was maintained at a temperature of 50° C., and the mixture was stirred and mixed using the stirrer 5 to prepare a slurry.
このスラリーを混合槽1の底部のバルブ6を開き、金型
2のキャビティー3の周囲を熱媒体を導入口8より導入
循環させて70℃に保持されたタービンホイール形状の
キャビティー3内に注入した。金型2をこの状態で10
分間保持して澱粉粒の皮膜を破りアミロースを溶出させ
た。その後、媒体の温度を下げ20℃まで金型を冷却さ
せた。This slurry is introduced and circulated around the cavity 3 of the mold 2 through the inlet 8 by opening the valve 6 at the bottom of the mixing tank 1, and then entering the turbine wheel-shaped cavity 3 maintained at 70°C. Injected. 10 with mold 2 in this state
The mixture was held for a minute to break the film on the starch granules and elute amylose. Thereafter, the temperature of the medium was lowered and the mold was cooled to 20°C.
固化した成形体を脱型し、真空乾燥機で70℃100T
orrの真空度で10時間乾燥して溶媒を除去した。The solidified molded body was demolded and dried in a vacuum dryer at 70°C and 100T.
The solvent was removed by drying for 10 hours at a vacuum level of orr.
乾燥後10℃/Hrの昇温速度で500℃まで昇温ざぜ
脱脂をおこなった。次に窒素雰囲気中で1800℃まで
加熱して焼結した。得られた焼結体はクラックや変形の
ない良好なものであった。After drying, the temperature was raised to 500°C at a heating rate of 10°C/Hr and degreased. Next, it was sintered by heating to 1800° C. in a nitrogen atmosphere. The obtained sintered body was in good condition with no cracks or deformation.
(比較例1)
比較例では澱粉粒を使用せず、溶媒の水の量を25容量
%とし、他は実施例と同様の方法でスラリーを作成した
。このスラリーを用いて実施例と同様の方法で型内で冷
却固化させ成形体を形成した。しかしこの成形体は脆く
脱型の際に割れが発生した。(Comparative Example 1) In a comparative example, starch granules were not used, and the amount of water as a solvent was 25% by volume, but a slurry was prepared in the same manner as in the example. Using this slurry, it was cooled and solidified in a mold to form a molded article in the same manner as in the examples. However, this molded product was brittle and cracked during demolding.
(比較例2)
実施例の方法において、スラリーの作成温度を55℃以
上でおこなったところ澱粉粒よりアミローズが溶出して
スラリーの粘度が高くなる。そのため実施例の方法では
型内に注入が困難であった。(Comparative Example 2) In the method of the example, when the slurry was prepared at a temperature of 55° C. or higher, amylose was eluted from the starch granules and the viscosity of the slurry increased. Therefore, it was difficult to inject into the mold using the method of the example.
(比較例3)
澱粉粒を可溶性澱粉に変えてスラリーを実施例と同様の
方法で作成した。しかしこのスラリーは粘度が高く低圧
での型内への注入が困難であった。(Comparative Example 3) A slurry was prepared in the same manner as in Example except that the starch granules were replaced with soluble starch. However, this slurry had a high viscosity and was difficult to inject into a mold at low pressure.
圧を高めて注入し型内で固化さぜ成形体を形成した。こ
の成形体は結合力が小さく乾燥、脱脂時に割れや、かけ
が発生した。The mixture was injected under increased pressure and solidified in the mold to form a molded body. This molded product had low bonding strength and cracked and chipped during drying and degreasing.
[効果コ
本発明のバインダー組成物は、構成成分の1つに澱粉粒
が含まれている。この澱粉粒を含むバインダーを用いて
形成したスラリーは、型内で加熱されるとアミロペクチ
ンの内部に存在するアミロースが澱粉粒外に溶出してゾ
ル化し、冷却によりゲル化して同化する。そのためこの
固化した成形体は脆さが解消される。そのため脱型の際
に型面にセラミックス粉末が張付いて成形体が割れたり
、かけが発生するのが抑制できる。また成形体の乾燥、
脱脂時の加熱に対しては、澱粉粒のアミロースとアミロ
ペクチンとで成形体を結合しているので、有機バインダ
ーが軟化してセラミックス成形体が変形したり破損した
りするのが抑制できる。[Effects] The binder composition of the present invention contains starch granules as one of its constituent components. When a slurry formed using a binder containing starch granules is heated in a mold, the amylose present inside the amylopectin is eluted out of the starch granules to form a sol, which is then cooled to gel and assimilate. Therefore, the brittleness of this solidified molded body is eliminated. Therefore, it is possible to prevent the ceramic powder from sticking to the mold surface during demolding, thereby preventing the molded product from cracking or chipping. Also, drying of the molded body,
With respect to heating during degreasing, since the molded body is bound by amylose and amylopectin in the starch granules, it is possible to prevent the organic binder from softening and deforming or breaking the ceramic molded body.
さらに澱粉粒は可溶澱粉と異なり高分子量であり、乾燥
、脱脂において有機バインダーと共に結合力を発揮する
ので成形体の変形が防止でき不良の発生を抑制できる。Furthermore, unlike soluble starch, starch granules have a high molecular weight and exhibit binding strength together with the organic binder during drying and degreasing, thereby preventing deformation of the molded product and suppressing the occurrence of defects.
したがって、複雑な形状のセラミックス成形体の成形を
効率良くおこなうことができ生産性が向上する。Therefore, a ceramic molded body having a complicated shape can be efficiently molded, and productivity is improved.
第1図は実施例で用いた成形機の概略説明図である。
1・・・混合槽 2・・・金型
3・・・ターどンホイール形状のキャビティ特許出願人
トヨタ自動車株式会社FIG. 1 is a schematic explanatory diagram of a molding machine used in Examples. 1... Mixing tank 2... Mold 3... Tardon wheel-shaped cavity Patent applicant Toyota Motor Corporation
Claims (1)
て成形体の形状を保持するバインダー組成物であつて、
溶媒と、有機バインダーと、澱粉粒とからなることを特
徴とするセラミックス成形用バインダー組成物。(1) A binder composition that is mixed with ceramic powder and solidified after being injected into a mold to maintain the shape of a molded object,
A binder composition for molding ceramics, comprising a solvent, an organic binder, and starch granules.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2191030A JPH0477352A (en) | 1990-07-19 | 1990-07-19 | Binder composition for molding ceramic |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2191030A JPH0477352A (en) | 1990-07-19 | 1990-07-19 | Binder composition for molding ceramic |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0477352A true JPH0477352A (en) | 1992-03-11 |
Family
ID=16267733
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2191030A Pending JPH0477352A (en) | 1990-07-19 | 1990-07-19 | Binder composition for molding ceramic |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0477352A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006062910A (en) * | 2004-08-26 | 2006-03-09 | Kyocera Corp | Ceramic composition, ceramic green sheet using the same and ceramic sintered compact |
US8633269B2 (en) | 2010-12-01 | 2014-01-21 | Mattel, Inc. | Play modeling dough |
JP2021126871A (en) * | 2020-02-17 | 2021-09-02 | 湖北工業株式会社 | Manufacturing method of molded body |
-
1990
- 1990-07-19 JP JP2191030A patent/JPH0477352A/en active Pending
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006062910A (en) * | 2004-08-26 | 2006-03-09 | Kyocera Corp | Ceramic composition, ceramic green sheet using the same and ceramic sintered compact |
US8633269B2 (en) | 2010-12-01 | 2014-01-21 | Mattel, Inc. | Play modeling dough |
JP2021126871A (en) * | 2020-02-17 | 2021-09-02 | 湖北工業株式会社 | Manufacturing method of molded body |
JP2021154751A (en) * | 2020-02-17 | 2021-10-07 | 湖北工業株式会社 | Manufacturing method of molded body |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP2843348B2 (en) | Formation of complex high performance ceramic and metal shapes | |
CN103071764A (en) | CaZrO3 mold shell used for titanium and titanium alloy precision casting and preparation method | |
JPS623064A (en) | Ceramics binder | |
JPH0555461B2 (en) | ||
JP2003535980A (en) | Aqueous injection molding binder composition and molding process | |
CA2364930A1 (en) | Metal/ceramic composite molding material | |
CA1125316A (en) | Sinterable powders and methods of producing sintered ceramic products using such powders | |
JPH03180402A (en) | Binding composition for use in injection or extrusion molding of metal or ceramic powder | |
JPH0477352A (en) | Binder composition for molding ceramic | |
KR20190128039A (en) | Binder for injection moulding compositions | |
JP2978152B2 (en) | Method for producing fibril-like article | |
WO2002045889A2 (en) | Improvement of flow characteristics of metal feedstock for injection molding | |
JP3313008B2 (en) | Clay composition for precious metal modeling and method for producing sintered precious metal product | |
CN113501721A (en) | Injection molding ceramic feed, preparation method of ceramic product and ceramic product | |
JP2677675B2 (en) | Method for producing sintered product consisting of powder molding binder and metal powder or ceramic powder | |
US4126653A (en) | Method of manufacturing silicon nitride products | |
US2519280A (en) | Method and composition for making ceramic articles | |
JPH0477349A (en) | Binder composition for forming ceramic | |
JPH0673405A (en) | 'metallic plastic composition | |
JPH0477350A (en) | Binder composition for molding ceramic | |
JPS60187445A (en) | Investment casting method and stucco material for said method | |
JPS61101447A (en) | Manufacture of ceramic formed body | |
JP2777673B2 (en) | Degreasing method of ceramic molded body | |
KR100428532B1 (en) | The precious metals sintered product and manufacture method it | |
JP3804108B2 (en) | Manufacturing method of ceramic sintered body |