JP2004141728A

JP2004141728A - Filter element and its manufacturing method

Info

Publication number: JP2004141728A
Application number: JP2002307440A
Authority: JP
Inventors: Naoki Kobayashi; 小林　直樹; Muneyuki Iwabuchi; 岩渕　宗之
Original assignee: NGK Insulators Ltd
Current assignee: NGK Insulators Ltd
Priority date: 2002-10-22
Filing date: 2002-10-22
Publication date: 2004-05-20
Anticipated expiration: 2022-10-22
Also published as: JP4040427B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter element which is compact, has excellent water permeability and is used suitably in process equipment in a field such as chemical industries and food industries, in domestic water purifier or in other fields and to provide a method for manufacturing the filter element. <P>SOLUTION: This filter element 1 consists of a porous body having a plurality of cells 9 through which an original liquid passes. At least one groove 4 is formed on one end 3a of the element 1, which has the prescribed depth from the end face 6a of the end 3a toward the inside and is extended almost linearly along the array of the prescribed cells 9 from one position on the edge of the face 6a to the other position to keep a diametral or chordal shape on the face 6a. A sealing material 5 is embedded from the face 6a to the depth shallower than the prescribed depth of the groove 4. A through-hole 7 is formed on the outer peripheral surface 2 of the element 1 by the groove 4 and the material 5, which is parted from the face 6a at the prescribed distance and penetrates the element 1 almost linearly from one position to the other position. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】本発明は、フィルタエレメント及びその製造方法に関する。さらに詳しくは、小型で通水性に優れ、特に、化学工業、食品工業等の分野におけるプロセス機器や家庭用の浄水器等に好適に用いられるフィルタエレメント及びその製造方法に関する。
【０００２】
【従来の技術】近年、化学工業、食品工業等の分野におけるプロセス機器や家庭用の水道水等に用いられる浄水器において、浄化すべき原液を、その内部を透過させることによって除菌、濾過等の浄化を行うフィルタとして、例えば、原液の流路となる複数のセルを有する多孔質体からなり、一方の端部から取り入れた浄化すべき原液を、その内部を透過させることによって浄化して浄化液として取り出すセラミックス製や中空糸製のフィルタエレメントが用いられおり、特に、その形状が変形しにくく、耐久性が高いことからセラミックス等のフィルタエレメントは様々な分野に渡って広く用いられている。
【０００３】通常、このフィルタエレメントは、通水量を確保しつつ濾過性能を向上させる観点から、比較的大きい細孔を有する多孔質体の表面を、比較的小さい細孔を有するセラミックス濾過膜で被覆したものが用いられており、高分子膜等と比較して、物理的強度、耐久性に優れるため信頼性が高いこと、耐食性が高いため酸アルカリ等による洗浄を行っても劣化が少ないこと、さらには、濾過能力を決定する細孔径の精密な制御が可能である点において優れており、特に、家庭用の浄水器等に好適に用いられている。
【０００４】従来、この家庭用の浄水器に関しては、浄水器本体の省スペース化と通水量の増加という二つの要望があり、このために、上述したフィルタエレメントも、小型化と通水量の増加とが要求されていた。
【０００５】しかしながら、フィルタエレメントはその大きさが小さくなるにつれて通水量が減少する傾向にあり、フィルタエレメントの小型化と通水量の増加とは二律背反の関係にあり、両者を両立させることは極めて困難であった。
【０００６】このため、筒状の多孔体（多孔質体）の長手方向に形成された、多数の平行な流通路（セル）の内周面に、多孔体の細孔に比して更に細孔径が小さい濾過膜を形成し、流通路に供給した被処理液体（原液）を濾過膜で濾過し、この濾過液が多孔体の細孔を透過して外部空間に流出するように構成するとともに、多孔体中心部近傍の流通路からの通水量を増加するために、多孔体の長手方向にスリット状の空隙部を設け、かつ、この空隙部と連通する流通路の縁端部を封止してなるセラミックフィルタにおいて、スリット状の空隙部を、筒状の多孔体の長手方向の中央部のみに設けた構成のセラミックスフィルタが開示されている（特許文献１参照）。
【０００７】
【特許文献１】
特開２０００−１５３１１７号公報
【０００８】
【発明が解決しようとする課題】しかしながら、このようなセラミックスフィルタは、本来、大型、例えば、体積が３．９Ｌ以上、長さ５００ｍｍ以上、端面の直径１００ｍｍ以上のフィルタに関するものであり、家庭用の浄水器等に用いられる小型、例えば、体積が１．２Ｌ以下、長さ１５０ｍｍ以下、端面の直径１００ｍｍ以下のフィルタに応用することは、前述した流通路を区画する多孔体が、空隙部を形成する際に破損することがあることから極めて困難であるという問題があった。
【０００９】本発明は、上述の問題に鑑みなされたもので、小型で通水性に優れ、特に、化学工業、食品工業等の分野におけるプロセス機器や家庭用の浄水器等に好適に用いられるフィルタエレメント及びその製造方法を提供することを目的とする。
【００１０】
【課題を解決するための手段】上述の目的を達成するため、本発明は、以下のフィルタエレメント及びその製造方法を提供するものである。
【００１１】
［１］　原液の流路となる複数のセルを有する多孔質体からなり、一方の端部から取り入れた浄化すべき前記原液を、その内部を透過させることによって浄化して外周面側から浄化液として取り出す所定形状のフィルタエレメントであって、前記一方の端部に、その端面側から内部に向かって所定の深さを有するとともに、所定の前記セルの並びに沿って前記一方の端面の端縁の一の部位から他の部位に渡ってほぼ直線状に延びる少なくとも一本の溝が形成されてなるとともに、前記溝のうち、前記一方の端面側から前記溝の所定の深さに達しない深さまでの部分に封止材が埋め込まれてなり、前記溝と前記封止材とによって、その外周面の、前記一方の端面側から所定距離離れた一の部位から他の部位までほぼ直線状に貫通する貫通孔が形成されてなることを特徴とするフィルタエレメント。
【００１２】
［２］　他方の端部の、前記一の端部における前記封止材が埋め込まれた前記溝の部分に対応する部位に、前記封止材と同一材質の目詰材が配設されてなる前記［１］に記載のフィルタエレメント。
【００１３】
［３］　少なくともいずれか一方の前記端部の、前記端面を含む表面にシール層が形成されてなる前記［１］又は［２］に記載のフィルタエレメント。
【００１４】
［４］　前記端面の直径が５０〜１００ｍｍであるとともに、軸方向の長さが５０〜１５０ｍｍの円柱形状である前記［１］〜［３］のいずれかに記載のフィルタエレメント。
【００１５】
［５］　浄水器用フィルタエレメントである前記［１］〜［４］のいずれかに記載のフィルタエレメント。
【００１６】
［６］　水圧０．１ＭＰａにおける通水量が３〜３０Ｌ／ｍｉｎである前記［５］に記載のフィルタエレメント。
【００１７】
［７］　原料を押出成形して原液の流路となるセルを有する多孔質体からなる所定形状の未焼成フィルタ成形体を得、得られた前記未焼成フィルタ成形体を乾燥及び焼成して焼成フィルタ成形体を得、得られた前記焼成フィルタ成形体の一方の端部に、その端面側から内部に向かって所定の深さを有するとともに、所定の前記セルの並びに沿って前記一方の端面の端縁の一の部位から他の部位に渡って少なくとも一本の溝を形成して、溝付きフィルタ成形体を得、得られた前記溝付きフィルタ成形体の前記溝のうち、前記一方の端面側から前記溝の所定の深さに達しない深さまでの部分だけに封止材を埋め込んで、前記溝付きフィルタ成形体の外周面の、前記一方の端面側から所定距離離れた一の部位から他の部位までほぼ直線状に貫通する貫通孔を有する貫通孔付きフィルタ成形体を得、得られた前記貫通孔付きフィルタ成形体を再度焼成してフィルタエレメントを得ることを特徴とするフィルタエレメントの製造方法。
【００１８】
［８］　他方の端部の、前記一の端部における前記封止材が埋め込まれた前記溝の部分に対応する部位に、前記封止材と同一材質の目詰材を配設する工程を含む前記［７］に記載のフィルタエレメントの製造方法。
【００１９】
［９］　少なくともいずれか一方の前記端部の、前記端面を含む表面にシール層を形成する工程を含む前記［７］又は［８］に記載のフィルタエレメントの製造方法。
【００２０】
【発明の実施の形態】以下、本発明のフィルタエレメントの実施の形態を、図面を参照しつつ具体的に説明する。
【００２１】図１は、本発明のフィルタエレメントの一の実施の形態を模式的に示す平面図であって、（ａ）は側面側からの平面図、（ｂ）は一方の端面側からの平面図である。
【００２２】図１（ａ）及び（ｂ）に示すように、本実施の形態のフィルタエレメント１は、原液の流路となる複数のセル９を有する多孔質体からなり、一方の端部３ａから取り入れた浄化すべき原液を、その内部を透過させることによって浄化して外周面２側から浄化液として取り出す所定形状のフィルタエレメント１であって、一方の端部３ａに、その一方の端面６ａ側から内部に向かって所定の深さを有するとともに、所定のセル９の並びに沿って一方の端面６ａの端縁の一の部位から他の部位に渡って円形における直径又は弦の形状を保持するようにほぼ直線状に延びる少なくとも１本の溝４が形成されてなるとともに、溝４のうち、一方の端面６ａ側から溝４の所定の深さに達しない深さまでの部分に封止材５が埋め込まれてなり、溝４と封止材５とによって、その外周面２の、一方の端面６ａ側から所定距離離れた一の部位から他の部位までほぼ直線状に貫通する貫通孔７が形成されてなることを特徴とする。
【００２３】本実施の形態のフィルタエレメント１は、セル９を区画する多孔質体の隔壁８が実質的に原液を濾過するフィルタとなる。
【００２４】このフィルタエレメント１の一方の端面６ａから流入した原液は、セル９を通過して、多孔質体の隔壁８を透過することによって濾過される、この後、外周面２側から浄化液として排出されるとともに、溝４が形成された部位に対応するセル９は貫通孔７とつながっているために、隔壁８を透過して貫通孔７とつながるセル９に流入した浄化液が貫通孔７からも排出される。
【００２５】このように構成することによって、浄化液の通水性に優れたものとすることができ、例えば、家庭用の浄水器等に用いられた場合、その形状を小型化したとしても、従来のフィルタエレメントと比較してその通水量を保持又は向上させることができる。
【００２６】本実施の形態のフィルタエレメント１に用いられる多孔質体の材質としては、フィルタとして用いることができる多孔質体であれば特に制限はないが、強度、耐久性の観点からセラミックスであることが好ましい。また、セラミックスの種類や製法に特に制限はないが、骨材と基体用焼結助剤から形成されたものであることが好ましい。骨材は基体の主成分を構成するセラミックス製の粒子であり、例えば、アルミナ、ムライト、コージェライト、炭化珪素、窒化珪素、窒化アルミニウム、陶磁器屑等の１種又は２種以上の粒子が好ましく、濾過の目的に適合するように適宜選択される。骨材の平均粒子径は、好ましくは５〜２００μｍ程度である。骨材の基体中の含有量は、骨材と基体用焼結助剤の合計を基準として、好ましくは６５〜９９．５質量％である。また、骨材と基体用焼結助剤に、メチルセルロースやポリエチレングリコールオレイン酸エステル等の成形バインダーを加えたものを用いてもよい。
【００２７】また、多孔質体の細孔径はフィルタエレメント１の目的・用途に応じて適宜選択することができる。
【００２８】基体用焼結助剤は、上記骨材とともに焼成することにより骨材間の結合を強化し、強固な多孔質体を形成するために用いられるものである。その材質は特に限定されないが、例えば、アルミナ、シリカ、ジルコニア、チタニア、ガラスフリット、長石、コージェライト、タルク、ガイロメ粘土等の１種又は２種以上を用いることができ、濾過の目的や骨材の材質によって適宜選択することができる。基体用焼結助剤の平均粒子径に特に制限はないが、５μｍ以下の平均粒子径であることが好ましい。基体用焼結助剤の含有量は、骨材と基体用焼結助剤の合計を基準として、好ましくは０．５〜３５質量％である。製造方法は後に詳述するが、このような骨材と焼結助剤を含む坏土を任意の形状に成形した後、焼成することにより多孔質のフィルタエレメント１を形成することができる。
【００２９】また、前述した溝４の幅は、フィルタエレメント１の大きさにもよるが、例えば、体積が０．２８３Ｌのフィルタエレメント１の場合、０．３〜３ｍｍであることが好ましい。溝４の幅が０．３ｍｍ未満であると、通水量を増加する効果が得られないことがあり、また、３ｍｍを超えると、フィルタエレメント１の機械的強度が低下し、この溝４からフィルタエレメント１が破損することがある。
【００３０】また、同様に、溝４の深さもフィルタエレメント１の大きさによって異なるが、例えば、体積が０．２８３Ｌのフィルタエレメント１の場合、２〜４０ｍｍであることが好ましい。溝４の深さが２ｍｍ未満であると、通水量を増加する効果が得られないことがあるとともに、一方の端面６ａ側から溝４の所定の深さに達しない深さまでの部分に封止材を埋め込むことが困難となることがあり、また、４０ｍｍを超えると、フィルタエレメント１の機械的強度が低下し、溝４からフィルタエレメント１が破損することがある。
【００３１】また、封止材５は、この溝４の底面から１．０〜２０ｍｍの隙間を形成するように埋め込まれている。本実施の形態のフィルタエレメント１においては、貫通孔７の外周面の開口面積が、０．３〜１１７ｍｍ^２であることが好ましい。
【００３２】封止材５の材質に特に制限はないが、隔壁８等がセラミックスから形成されている場合には、強度及び基体との接着性の観点からセラミックスであることが好ましく、隔壁８等に含まれる成分の一部と同様の成分を含むセラミックスであることがさらに好ましい。また、封止材５の材料は、収縮が大きすぎると割れが発生しやすくなるため、収縮の小さな材料であることが好ましい。
【００３３】本実施の形態においては、隔壁８を構成する多孔質体のみで濾過を行ってもよいが、処理速度を確保しつつ分離性能を向上させる観点からは、比較的細孔径の大きな隔壁８を多孔質基体とし、この多孔質基体の表面に、これよりも細孔径の小さい濾過膜１０を形成することが好ましい。このような構成とすることによって、濾過膜１０の平均細孔径を小さくしても、原液がフィルタエレメント１内部を透過する際の圧力損失を抑えることができる。この場合には、図２に示すように、セル９を区画する隔壁８の表面上に濾過膜１０を形成することが上記目的を効率よく達成できる点で好ましい。濾過膜１０の平均細孔径はフィルタエレメント１の用途・目的、即ち、浄化すべき原液中に含まれる異物の粒径によって適宜選択することができるが、例えば、本実施の形態のフィルタエレメント１を浄水器に用いる場合には、濾過膜１０の平均細孔径は、０．１〜２．０μｍ程度が好ましく、０．２〜０．７μｍ程度がさらに好ましい。
【００３４】濾過膜１０の材質に特に制限はないが、セラミックス粒子と濾過膜用焼結助剤を含むことが好ましい。セラミックス粒子には、骨材に好ましいものとして挙げた上述の材料の中から選択して使用することが好ましく、その平均粒子径は０．１〜１０μｍ程度であることが好ましい。より小さい粒子径を選択することにより、焼成後の細孔径が小さくなるため、粒子径は濾過の目的に応じて適切な細孔径となるよう適宜選択することができ、例えば、浄水器に使用するような範囲の細孔径を得ようとする場合は、セラミックス粒子の平均粒子径を０．２〜５．０μｍ程度とすることが好ましく、０．４〜２．５μｍ程度とすることが好ましい。濾過膜用焼結助剤も、基体用焼結助剤に好ましいものとして挙げた材料の中から選択して使用することが好ましい。セラミックス粒子と濾過膜用焼結助剤の比率は、セラミックス粒子と濾過膜用焼結助剤の合計を基準としてセラミックス粒子が好ましくは８５〜９９．５質量％含まれ、濾過膜用焼結助剤が、好ましくは０．５〜１５質量％含まれる。濾過膜１０は、これらのセラミックス粒子と濾過膜用焼結助剤をスラリー状として基体表面に施与した後焼成することによって形成することができる。また、濾過膜１０は、１層であってもよいが、２層以上としてもよく、その場合は最外層の濾過膜１０の平均細孔径を最も小さくし、隔壁８に向かって順に細孔径を大きくすることが好ましい。
【００３５】また、本実施の形態においては、フィルタエレメント１の他方の端部３ｂの、一の端部３ａにおける封止材５が埋め込まれた溝４の部分に対応する部位に、封止材５と同一材質の目詰材１１が配設されてなることが好ましい。このように構成することにより、原液が濾過されずに貫通孔７から排出されることを防止することができる。
【００３６】また、図１（ａ）及び図２に示すように、フィルタエレメント１の少なくともいずれか一方の端部３の、その端面６を含む表面にシール層１２が形成されてなることが好ましい。このように構成することによって、前述しようにフィルタエレメント１が濾過膜１０を有する場合、濾過膜１０の形成されていない、フィルタエレメントの端部３からの原液が透過することを防止できる。また、図３に示すように、フィルタエレメント１を浄水器等に固定する場合、原液の流入又は滞留する端面６と浄水が流出する外周面２とを、シリコンやフッ素系樹脂等のパッキン１３を用いて液密に固定する際に、その確実性を高めることができる。
【００３７】このシール層１２の材質は、特に制限はないが、フィルタエレメント１がセラミックスである場合には、強度及び基体との接着性の観点からセラミックスであることが好ましく、隔壁８（図２参照）に含まれる成分の一部と同様の成分を含むセラミックスであることがさらに好ましい。但し、実質的に原液を透過させないことが必要とされるため、セラミックスをフリット化させた釉薬等、特にシリカ及びアルミナを主成分として、これに１０質量％以下のジルコニアを含むフリット化された釉薬等が好ましく、バインダーとしてメチルセルロースを含んでいてもよい。
【００３８】また、本実施の形態のフィルタエレメント１の大きさは、特に制限はなく、用途・目的、設置場所等に応じてあらゆる形状とすることができが、例えば、家庭用の浄水器用のフィルタエレメント１として用いる場合には、端面の直径が５０〜１００ｍｍであるとともに、軸方向の長さが５０〜１５０ｍｍの円柱形状であることが好ましい。また、大きさも、処理量や設置場所等に応じて適宜選択することができる。
【００３９】また、フィルタエレメント１の通水量は、特に限定されることはないが、浄水器用のフィルタエレメント１として用いる際は、水圧０．１ＭＰａにおける通水量が３〜３０Ｌ／ｍｉｎであることが好ましい。また、その端面の直径が６２ｍｍのフィルタエレメント１においては、軸方向の長さが１００ｍｍ当たり、７〜１３Ｌ／ｍｉｎの通水量であることが好ましく、端面の直径が９０ｍｍのフィルタエレメント１においては、軸方向の長さが１００ｍｍ当たり、１５〜２５Ｌ／ｍｉｎの通水量であることが好ましい。このように構成することによって、本実施の形態のフィルタエレメント１が、家庭用の浄水器の一般的な通水量の仕様を十分に満足しうるものとすることができる。
【００４０】また、図１（ｂ）に示すように、本実施の形態においは、フィルタエレメント１が有するセル９の断面形状が円形のものを示しているが、これに限定されることはなく、三角形、四角形、五角形、六角形等の任意の多角形の他、円形、楕円形等やコルゲート形状等とすることができるが、隔壁８及び濾過膜１０の強度の観点及び濾過膜１０を均一に形成できる観点で円形状又は略円形状であることが好ましい。ここで略円形状には、楕円形、長円形、オーバル形状等の他、多角形の頂点が丸められた形状等も含む。セル９の断面の大きさにも特に制限はないが、断面が小さすぎると原液の流入時の抵抗が大きくなりすぎることがあり、逆に断面が大きすぎると十分な濾過面積をとることができなくなることがある。セル９の断面積の好ましい範囲は、原液の粘度によっても異なるが、例えば、本実施の形態のフィルタエレメント１を浄水器に用いる場合、０．２〜２０ｍｍ^２であることが好ましく、０．５〜１０ｍｍ^２であることがさらに好ましい。このような範囲にすることにより、濾過膜１０を形成させる際の成膜を均一に行いやすく、また、単位体積当たりの濾過膜１０の面積を比較的大きくとれる、即ち、フィルタエレメント１を小型化することができる。また、セル９の数に特に制限はなく、強度、大きさ及び処理量の関係から当業者であれば適宜選択することができる。
【００４１】また、フィルタエレメント１が有するセル９の配列状態は特に限定されることはないが、セル９の数が多いほど濾過膜面積がとれるので通水量の向上が図れ、よりフィルタエレメント１のコンパクト化が実現される。好ましい配列としては、セル９の端面における形状を円として各セル９の中心を結び正三角形の配置で最密充填させるこる。この際のセル９間の隔壁８の厚さは多孔質体を構成する平均粒子径の５〜３０倍、又はセル９の直径の０．１〜１倍とすることが好ましい。隔壁８の厚さが、多孔質体を構成する平均粒子径の５倍未満であると多孔質体の強度が低過ぎて多孔質体を成形できないことがあり、３０倍を超えるとセル９が最密充填できないことがある。また、セル９の直径の０．１倍未満であると多孔質体の強度が低過ぎて成形できないことがあり、１倍を超えるとセル９が最密充填できなくなることがある。
【００４２】次に、本発明のフィルタエレメントの製造方法の一の実施の形態について、図面を用いて具体的に説明する。
【００４３】本実施の形態のフィルタエレメントの製造方法の製造方法は、まず、図４に示すように、原料を押出成形して原液の流路となるセル９を有する多孔質体からなる所定形状の未焼成フィルタ成形体２０を得る。この原料は、例えば、上述の好ましい骨材及び好ましい基体用焼結助剤の中から選択した骨材及び基体用焼結助剤を上述の好ましい比率（骨材：基体用焼結助剤＝６５〜９５質量％：３５〜５質量％）で用意し、これに分散媒、有機バインダー、必要により界面活性剤、可塑剤等を添加し、ニーダー混練機等を用いて混練して坏土とする。これを、例えば、真空押出し成形機を用いて、所望の形状、本実施の形態においては、円柱状に押出成形する。
【００４４】次に、得られた未焼成フィルタ成形体２０を乾燥及び焼成して焼成フィルタ成形体を得る。乾燥の方法としては、例えば、電子レンジ等を用いて１５分間予備乾燥を行い、その後、乾燥器を用いて、未焼成フィルタ成形体２０の水分が３質量％以下となるよう乾燥する。
【００４５】乾燥を終えた後に焼成を行うのであるが、製造するフィルタエレメント１（図２参照）が、上述した濾過膜１０（図２参照）を有するものである場合には、未焼成フィルタ成形体２０を焼成する前に、図５に示すように、濾過膜１０（図２参照）を成膜する工程において、未焼成フィルタ成形体２０の中心部と外周部とに濾過膜１０（図２参照）が均一に成膜されるように、その端面側から内部に向かって所定の深さを有するとともに、所定のセル９の並びに沿って一方の端面の端縁の一の部位から他の部位に渡って、円形における直径又は弦の形状を保持するようにほぼ直線状に延びる少なくとも１本の仮溝２１を形成する。本実施の形態においては、深さ１５ｍｍの仮溝２１を２本形成した。仮溝２１は、円盤状のカッター２２や金のこ（図示せず）等を用いて容易に形成することができる。また、濾過膜１０（図２参照）を有していないフィルタエレメントを製造する場合は、この工程は省略してもよい。
【００４６】次に、図６に示すように、未焼成フィルタ成形体２０の仮溝２１に、前述した原材料と略同一の仮封止材２３を埋め込む。この際、一方の端面側から仮溝２１の所定の深さに達しない深さまでの部分に仮封止材２３が埋め込まれるように、仮溝２１の幅と同程度の厚さの板状部材２４を仮溝２１に配設し、未焼成フィルタ成形体２０の一方の端面にへら２５等を用いて仮封止材２３を押し込むことが好ましい。また、上述したように仮溝２１を形成する工程を省略した場合は、この工程も省略してもよい。
【００４７】次に、乾燥した未焼成フィルタ成形体２０を、例えば、平均粒子径８０μｍのアルミナを目砂に用いて、１０００〜１６００℃の最高温度で０．１〜３時間焼成して焼成フィルタ成形体を得る。
【００４８】次に、得られた焼成フィルタ成形体に濾過膜１０を形成する。上述したように、濾過膜１０（図２参照）を有していないフィルタエレメントを製造する場合は、この工程を省略してもよい。濾過膜１０（図２参照）を形成する成膜工程は、例えば、図７に示すような、動加圧真空法を用いた成膜装置を用いて行うことができる。上述の好ましいセラミックス粒子の中から選択したセラミックス粒子単独、又はこのセラミックス粒子と上述の好ましい濾過膜用焼結助剤の中から選択した焼結助剤を、セラミックス粒子／濾過膜用焼結助剤の質量比で、好ましくは７５〜９９．５／２５〜０．５、さらに好ましくは８０〜９５／２０〜５の比率で混合した成膜スラリー２７を用意し、焼成フィルタ成形体２８をフィルタとして成膜スラリー２７を濾過することにより、成膜スラリー２７の固形分が隔壁８（図２参照）の表面に濾過膜１０（図２参照）として成膜される。モノリス形状のセル９（図２参照）に成膜スラリー２７を流し、循環させ、濾過膜１０（図２参照）が隔壁８（図２参照）の表面に所定の厚さで成膜される分に相当する量（焼成フィルタ成形体２８の隔壁８（図２参照）の表面積×濾過膜１０（図２参照）の厚さ×成膜スラリー２７の密度）の濾過水２９を排出する。また、成膜された濾過膜１０（図２参照）の形状が保持されるように、濾過水２９回収後、濾過水側から焼成フィルタ成形体２８を真空脱水する。この後、３０〜６０℃で、濾過膜１０（図２参照）を成膜した焼成フィルタ成形体２８を乾燥させた後、選択したセラミックス粒子及び焼結助剤に応じた所定の温度及び時間、例えば、９００〜１４５０℃の最高温度で０．１〜３時間程度保持し、焼成する。
【００４９】次に、濾過膜１０（図２参照）を成膜した焼成フィルタ成形体２８を、所定の長さ、本実施の形態においては、その長さが１００ｍｍとなるように、ダイヤモンドカッター等を用いて切断し、切断した焼成フィルタ成形体２８の一方の端部に、図８に示すように、その端面側から内部に向かって所定の深さを有するとともに、所定のセル９の並びに沿って一方の端面の端縁の一の部位から他の部位に渡って円形における直径又は弦の形状を保持するようにほぼ直線状に延びる二本の溝４を形成して、溝付きフィルタ成形体３０を得る。この溝４は、例えば、厚さ０．６ｍｍの回転刃３６を有する溝加工機３２等を用いて容易に形成することができる。また、溝加工の際に、例えば、Ｖ字型の位置出し治具３３を用いると位置決めが容易になる。
【００５０】また、この溝４の幅は、製造するフィルタエレメント１（図１（ａ）参照）の大きさにもよるが、例えば、体積が０．２８３Ｌのフィルタエレメント１（図１（ａ）参照）を製造する場合、０．３〜３．０ｍｍであることが好ましい。溝４の幅が０．３ｍｍ未満であると、通水量を増加する効果が得られないことがあり、また、３ｍｍを超えると、フィルタエレメント１（図１（ａ）参照）の機械的強度が低下し、この溝４からフィルタエレメント１（図１（ａ）参照）が破損することがある。
【００５１】また、同様に溝４の深さも、フィルタエレメント１（図１（ａ）参照）の大きさによって異なるが、例えば、体積が体積が０．２８３Ｌのフィルタエレメント１（図１（ａ）参照）を製造する場合、２〜４０ｍｍであることが好ましい。溝４の深さが２ｍｍ未満であると、通水量を増加する効果が得られないことがあるとともに、一方の端面側から溝４の所定の深さに達しない深さまでの部分に封止材５（図１（ａ）参照）を埋め込むことが困難となることがあり、また、４０ｍｍを超えると、フィルタエレメント１（図１（ａ）参照）の機械的強度が低下し、この溝４からフィルタエレメント１（図１（ａ）参照）が破損することがある。
【００５２】次に、図９に示すように、得られた溝付きフィルタ成形体３０（図８参照）の溝４のうち、一方の端面側から溝４の所定の深さに達しない深さまでの部分だけに封止材５を埋め込んで、溝付きフィルタ成形体３０（図８参照）の外周面の、一方の端面側から所定距離離れた一の部位から他の部位までほぼ直線状に貫通する貫通孔７を有する貫通孔付きフィルタ成形体３１を得る。封止材５を埋め込む方法としては、図６に示した仮封止材２３を埋め込む方法と同様に行うことができる。
【００５３】封止材５は、溝４の底面から１．０〜２０ｍｍの隙間を有するように埋め込むことが好ましい。また、封止材５の材料としては、特に制限はないが、前述した未焼成フィルタ成形体２０（図４参照）の原料と略同一のものを好適に用いることができる。
【００５４】また、この際、他方の端部の、一の端部における封止材が埋め込まれた溝４の部分に対応する部位に、封止材５と同一材質の目詰材１１（図２参照）を配設してもよい。
【００５５】さらに、図１０に示すように、このような貫通孔付きフィルタ成形体３１の少なくともいずれか一方の端部の、端面を含む表面にシール層１２を形成してもよい。シール層１２の材料としては、上述したような釉薬等を好適に用いることができ、シール層１２を形成する方法としては、貫通孔付きフィルタ成形体３１を回転させるための回転治具３４を用いて回転させながら、液体状の釉薬等をスプレーガン２５を用いて、霧状にして端面に塗布し、塗布した釉薬等を自然乾燥させてシール層１２を形成する。
【００５６】次に、得られた貫通孔付きフィルタ成形体３１を、例えば、平均粒子径８０μｍのアルミナを目砂に用いて、９００〜１６００℃の最高温度で０．１〜３時間焼成して再度焼成してフィルタエレメント１（図１（ａ）参照）を得る。
【００５７】このように構成することによって、小型で通水性に優れ、特に、化学工業、食品工業等の分野におけるプロセス機器や家庭用の浄水器等に好適に用いられるフィルタエレメントを簡便かつ低コストに製造することができる。
【００５８】
【実施例】以下、本発明を実施例により具体的に説明するが、本発明はこれらの実施例に限定されるものではない。
【００５９】（実施例１）
原料として、平均粒子径８０μｍ、純度９８％以上のアルミナ９０質量％に焼結助剤としてタルク／ガイロメ粘土を１０質量％を加え、この合計１００質量部に対して成形バインダーとしてメチルセルロースを４．５質量部、潤滑材としてポリエチレングリコールオレイン酸エステルを１質量部、及び水を１０質量部を加えて、これらをニーダーで混練して押出し用の坏土を調製した。
【００６０】次に、真空押出し成形機を用いて、φ２ｍｍのセルを４９９個有し、端面の形状がφ６２ｍｍ、長さが１０００ｍｍのモノリス形状の未焼成フィルタ成形体を押出し成形した。成形後、メチルセルロースを硬化させ形状を保持させることを目的に電子レンジを用いて１５分間予備乾燥をさせ、その後、乾燥器を用いて、未焼成フィルタ成形体の水分が３質量％以下となるように８０℃で１６時間乾燥させた。
【００６１】次に、未焼成フィルタ成形体の中心部と外周部が均一に濾過膜が形成されるように、図５に示したような、所定のセルの並びに沿って一方の端面の端縁の一の部位から他の部位に渡って円形における直径又は弦の形状を保持するようにほぼ直線状に延びる、幅１ｍｍ、深さ１５ｍｍの仮溝を形成した。
【００６２】次に、焼成フィルタ成形体の仮溝に、平均粒子径８０μｍ、純度９８％以上のアルミナ８０質量％に焼結助剤としてアルミナ／ジルコニア系ガラスを２０質量％加え、この合計１００質量部に対してポリビニルアルコールを外配で１０質量部加えて混錬した仮封止材を埋め込んだ。この際、一方の端面側から仮溝の所定の深さに達しない深さまでの部分に仮封止材が埋め込まれるように、仮溝の幅と同程度の厚さの板状部材を仮溝に配設した。
【００６３】次に、乾燥した未焼成フィルタ成形体を、平均粒子径８０μｍのアルミナを目砂に用いて、１２５０℃の最高温度で１時間焼成して焼成フィルタ成形体を得た。
【００６４】次に、平均粒子径２．５μｍ、純度９８％以上のアルミナ９０質量％に焼結助剤としてアルミナ／ジルコニア系ガラスを１０質量％加え、この合計１００質量部に対して解こう剤としてポリカルボン酸アンモニウムを１．０質量部、保形剤として多糖類を５質量部、及び水を９０質量部加えて、攪拌機を用いて攪拌して成膜用スラリーを調整し、図７に示した加圧真空法を用いた成膜装置２６を用いて、焼成フィルタ成形体の隔壁の表面に、厚さ約２００μｍとなるように成膜した。濾過膜を成膜した後、３０〜６０℃で、焼成フィルタ成形体を乾燥させ、その後、平均粒子径８０μｍのアルミナを目砂に用いて、さらに１０００℃で１時間焼成した。
【００６５】次に、焼成フィルタ成形体の長さが１００ｍｍとなるように端部を切断し、切断した焼成フィルタ成形体の一方の端部に、その端面側から内部に向かって所定の深さを有するとともに、一方の端面の端縁の一の部位から他の部位に渡って円形における直径又は弦の形状を保持するようにほぼ直線状に延びる、幅１ｍｍ、深さ１５ｍｍの溝を２本形成して、溝付きフィルタ成形体を得た。
【００６６】次に、得られた溝付きフィルタ成形体の溝のうち、一方の端面側から１０ｍｍの深さまでの部分だけに封止材を埋め込んで、溝付きフィルタ成形体の外周面の、一方の端面側から所定距離離れた一の部位から他の部位までほぼ直線状に貫通する幅１×１０ｍｍの貫通孔を有する貫通孔付きフィルタ成形体を得た。封止材は、平均粒子径８０μｍ、純度９８％以上のアルミナ８０質量％に焼結助剤としてアルミナ／ジルコニア系ガラスを２０質量％加え、この合計１００質量部に対してポリビニルアルコールを１０〜２０質量部加えて混錬したものを、仮封止材と同様の方法を用いて埋め込んだ。また、溝付きフィルタ成形体の他方の端部の、一の端部における封止材が埋め込まれた溝の部分に対応する部位に、封止材と同一材質の目詰材を配設した。
【００６７】また、溝付きフィルタ成形体の両端部の、端面を含む表面に、アルミナ／ジルコニア系ガラスと、バインダーとしてメチルセルロース２質量％水溶液と、質量比が同じになるように混ぜ合わせ釉薬スラリーを、図９に示すように、溝付きフィルタ成形体を回転させながら、釉薬スラリーをスプレーガンを用いて、霧状にして端面に塗布し、塗布した釉薬等を自然乾燥させてシール層を形成した。
【００６８】次に、得られた貫通孔付きフィルタ成形体を、平均粒子径８０μｍのアルミナを目砂に用いて、例えば、１０００℃の最高温度で１時間焼成して再度焼成してフィルタエレメントを得た。
【００６９】得られたフィルタエレメント（実施例１）の流入口となる一方の端面側から、水圧０．１ＭＰａ、温度２０℃の条件で、１分間純水を流し、通水量（Ｌ／ｍｉｎ）を測定した。測定結果を表１に示す。
【００７０】
【表１】

【００７１】（実施例２，３）
貫通孔を３本形成した以外は実施例１と同様に構成されたフィルタエレメント（実施例２）と、貫通孔を４本形成した以外は実施例１と同様に構成されたフィルタエレメント（実施例３）とを、上述して方法と同様にして製造した。得られたフィルタエレメント（実施例２，３）の流入口となる一方の端面側から、水圧０．１ＭＰａ、温度２０℃の条件で、１分間純水を流し、通水量（Ｌ／ｍｉｎ）を測定した。測定結果を表１に示す。
【００７２】（比較例１）
実施例１と同様の材料を用いて、貫通孔を形成せずにフィルタエレメント（比較例１）を製造した。得られたフィルタエレメント（比較例１）の流入口となる一方の端面側から、水圧０．１ＭＰａ、温度２０℃の条件で、１分間純水を流し、通水量（Ｌ／ｍｉｎ）を測定した。測定結果を表１に示す。
【００７３】表１に示すように、貫通孔を有するフィルタエレメント（実施例１〜３）は、貫通孔のないフィルタエレメント（比較例１）に比較して、通水量が多くなっていた。
【００７４】
【発明の効果】以上説明したように、本発明によって、小型で通水性に優れ、特に、化学工業、食品工業等の分野におけるプロセス機器や家庭用の浄水器等に好適に用いられるフィルタエレメント及びその製造方法を提供することができる。
【図面の簡単な説明】
【図１】本発明のフィルタエレメントの一の実施の形態を模式的に示す平面図であって、（ａ）は側面側からの平面図、（ｂ）は一方の端面側からの平面図を示す。
【図２】本発明のフィルタエレメントの一の実施の形態を模式的に示す断面図である。
【図３】本発明のフィルタエレメントの一の実施の形態を模式的に示す平面図である。
【図４】本発明のフィルタエレメントの製造方法の一の実施の形態において得られた未焼成フィルタ成形体を模式的に示す斜視図である。
【図５】本発明のフィルタエレメントの製造方法の一の実施の形態における、未焼成フィルタ成形体に仮溝を形成する工程を示す斜視図である。
【図６】本発明のフィルタエレメントの製造方法の一の実施の形態における、未焼成フィルタ成形体に仮封止材を埋め込む工程を示す斜視図である。
【図７】本発明のフィルタエレメントの製造方法の一の実施の形態に用いられる成膜装置の構成を模式的に示す説明図である。
【図８】本発明のフィルタエレメントの製造方法の一の実施の形態における、焼成フィルタ成形体に溝を形成する工程を示す斜視図である。
【図９】本発明のフィルタエレメントの製造方法の一の実施の形態において得られた貫通孔付きフィルタ成形体を模式的に示す斜視図である。
【図１０】本発明のフィルタエレメントの製造方法の一の実施の形態における、貫通孔付きフィルタ成形体にシール層を形成する工程を示す斜視図である。
【符号の説明】
１…フィルタエレメント、２…外周面、３…端部、３ａ…一方の端部、３ｂ…他方の端部、４…溝、５…封止材、６…端面、６ａ…一方の端面、７…貫通孔、８…隔壁、９…セル、１０…濾過膜、１１…目詰材、１２…シール層、１３…パッキン、２０…未焼成フィルタ成形体、２１…仮溝、２２…円盤状のカッター、２３…仮封止材、２４…板状部材、２５…へら、２６…成膜装置、２７…成膜スラリー、２８…焼成フィルタ成形体、２９…濾過水、３０…溝付きフィルタ成形体、３１…通孔付きフィルタ成形体、３２…溝加工機、３３…位置出し治具、３４…回転治具、３５…スプレーガン、３６…回転刃。[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter element and a method for manufacturing the same. More particularly, the present invention relates to a filter element that is small and excellent in water permeability, and particularly suitable for use in process equipment, household water purifiers, and the like in fields such as the chemical industry and the food industry, and a method for producing the same.
[0002]
2. Description of the Related Art In recent years, in water purifiers used for process equipment and household tap water in the fields of chemical industry, food industry, etc., sterilization, filtration, etc. are achieved by allowing the stock solution to be purified to permeate through the inside. As a filter for purifying, for example, it is made of a porous body having a plurality of cells serving as a flow path of the stock solution, and the stock solution to be purified taken in from one end is purified by passing through the inside thereof and purified. Ceramic filter elements or hollow fiber filter elements taken out as liquids are used. Particularly, filter elements such as ceramics are widely used in various fields because their shapes are not easily deformed and durability is high.
Usually, this filter element covers the surface of a porous body having relatively large pores with a ceramic filtration membrane having relatively small pores from the viewpoint of improving the filtration performance while ensuring the amount of water flow. Compared to polymer membranes, etc., it has high physical strength and durability, so it has high reliability, and because it has high corrosion resistance, it has little deterioration even when washed with acid alkali, etc. Furthermore, it is excellent in that precise control of the pore diameter that determines the filtration ability is possible, and it is particularly suitably used for household water purifiers and the like.
Conventionally, there are two demands for this water purifier for home use, that is, space saving of the water purifier body and an increase in the amount of water flow. For this reason, the above-described filter element is also reduced in size and increased in the amount of water flow. And was requested.
However, as the size of the filter element decreases, the water flow rate tends to decrease, and the downsizing of the filter element and the increase in the water flow rate are in a trade-off relationship, and it is extremely difficult to achieve both. Met.
For this reason, the inner circumferential surface of a large number of parallel flow passages (cells) formed in the longitudinal direction of the cylindrical porous body (porous body) is further finer than the pores of the porous body. A filtration membrane having a small pore diameter is formed, and the liquid to be treated (raw solution) supplied to the flow passage is filtered through the filtration membrane, and this filtrate passes through the pores of the porous body and flows out to the external space. In order to increase the amount of water flow from the flow passage near the center of the porous body, a slit-shaped gap is provided in the longitudinal direction of the porous body, and the edge of the flow passage communicating with the gap is sealed. In this ceramic filter, there is disclosed a ceramic filter having a configuration in which a slit-shaped gap is provided only at the center in the longitudinal direction of a cylindrical porous body (see Patent Document 1).
[0007]
[Patent Document 1]
JP 2000-153117 A
[0008]
However, such a ceramic filter is originally a large filter, for example, a filter having a volume of 3.9 L or more, a length of 500 mm or more, and an end face diameter of 100 mm or more. Is applied to a filter having a volume of 1.2 L or less, a length of 150 mm or less, and an end face diameter of 100 mm or less. There is a problem that it is extremely difficult because it sometimes breaks during formation.
The present invention has been made in view of the above-mentioned problems, and is small and excellent in water permeability. In particular, the filter is suitably used for process equipment in the fields of chemical industry, food industry, etc., household water purifiers, etc. It aims at providing an element and its manufacturing method.
[0010]
In order to achieve the above-mentioned object, the present invention provides the following filter element and manufacturing method thereof.
[0011]
[1] A porous body having a plurality of cells serving as a flow path for the stock solution, and purifying the stock solution to be purified, which is taken in from one end, by permeating the inside thereof, and purifying solution from the outer peripheral surface side. A filter element of a predetermined shape to be taken out as described above, having a predetermined depth from the end surface side to the inside at the one end portion, and an edge of the one end surface along a sequence of the predetermined cells. At least one groove extending substantially linearly from one part to another part is formed, and from the one end face side to the depth that does not reach the predetermined depth of the groove. A sealing material is embedded in the portion, and the groove and the sealing material penetrate substantially linearly from one part of the outer peripheral surface at a predetermined distance from the one end face side to the other part. Forming through-holes The filter element characterized by being made.
[0012]
[2] A clogging material made of the same material as that of the sealing material is disposed at a portion corresponding to the groove portion in which the sealing material is embedded in the one end portion of the other end portion. The filter element according to the above [1].
[0013]
[3] The filter element according to [1] or [2], wherein a seal layer is formed on a surface including the end face of at least one of the end portions.
[0014]
[4] The filter element according to any one of [1] to [3], wherein the end face has a cylindrical shape with a diameter of 50 to 100 mm and an axial length of 50 to 150 mm.
[0015]
[5] The filter element according to any one of [1] to [4], which is a filter element for a water purifier.
[0016]
[6] The filter element according to [5], wherein a water flow rate at a water pressure of 0.1 MPa is 3 to 30 L / min.
[0017]
[7] Extruding the raw material to obtain a green filter molded body having a predetermined shape made of a porous body having cells that serve as a flow path for the stock solution, and drying and firing the obtained green filter molded body A filter molded body is obtained, and one end portion of the obtained fired filter molded body has a predetermined depth from the end surface side toward the inside thereof, and the end surface of the one end surface along a predetermined array of the cells. Forming at least one groove from one part of the edge to the other part to obtain a grooved filter molded body, and among the grooves of the obtained grooved filter molded body, the one end surface From one side of the outer peripheral surface of the grooved filter molded body, a predetermined distance away from the one end face side, by embedding a sealing material only in a portion from the side to a depth not reaching the predetermined depth of the groove Penetrating almost linearly to other parts A filter element manufacturing method comprising: obtaining a filter molded body with through holes having through holes, and firing the obtained filter molded body with through holes again to obtain a filter element.
[0018]
[8] A step of disposing a clogging material of the same material as the sealing material in a portion corresponding to the groove portion in which the sealing material is embedded in the one end portion of the other end portion. The manufacturing method of the filter element as described in said [7] containing.
[0019]
[9] The method for manufacturing a filter element according to [7] or [8], including a step of forming a seal layer on a surface including the end face of at least one of the end portions.
[0020]
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a filter element according to the present invention will be specifically described below with reference to the drawings.
FIG. 1 is a plan view schematically showing one embodiment of the filter element of the present invention, where (a) is a plan view from the side surface, and (b) is from one end surface side. It is a top view.
As shown in FIGS. 1 (a) and 1 (b), the filter element 1 according to the present embodiment is made of a porous body having a plurality of cells 9 serving as a flow path for the stock solution, and has one end 3a. The filter element 1 having a predetermined shape is purified by allowing the stock solution to be purified taken in from the inside to permeate through the inside thereof, and is taken out as the purification solution from the outer peripheral surface 2 side. One end surface 6a is disposed on one end 3a. It has a predetermined depth from the side to the inside, and maintains a diameter or a chord shape in a circle from one part of the edge of one end face 6a to another part along the predetermined cell 9 Thus, at least one groove 4 extending substantially linearly is formed, and the sealing material 5 is formed in a portion of the groove 4 from one end face 6a side to a depth not reaching the predetermined depth of the groove 4. Become embedded The groove 4 and the sealing material 5 form a through-hole 7 that penetrates substantially linearly from one part of the outer peripheral surface 2 that is a predetermined distance away from the one end face 6a side to the other part. Features.
In the filter element 1 of the present embodiment, the porous partition walls 8 partitioning the cells 9 serve as a filter for substantially filtering the stock solution.
The stock solution flowing in from one end surface 6a of the filter element 1 passes through the cell 9 and is filtered by passing through the partition wall 8 of the porous body. Thereafter, the purification solution is introduced from the outer peripheral surface 2 side. Since the cell 9 corresponding to the portion where the groove 4 is formed is connected to the through hole 7, the cleaning liquid that has passed through the partition wall 8 and has flowed into the cell 9 connected to the through hole 7 passes through the through hole. 7 is also discharged.
With this configuration, it is possible to make the purifying solution excellent in water permeability. For example, when used in a domestic water purifier, even if its shape is reduced, The water flow rate can be maintained or improved as compared with the filter element.
The material of the porous body used in the filter element 1 of the present embodiment is not particularly limited as long as it is a porous body that can be used as a filter, but is ceramic from the viewpoint of strength and durability. It is preferable. Moreover, although there is no restriction | limiting in particular in the kind and manufacturing method of ceramics, It is preferable that it was formed from the aggregate and the sintering aid for base | substrates. Aggregates are particles made of ceramics that constitute the main component of the substrate. For example, one or more particles such as alumina, mullite, cordierite, silicon carbide, silicon nitride, aluminum nitride, and ceramic waste are preferable, It is appropriately selected so as to meet the purpose of filtration. The average particle diameter of the aggregate is preferably about 5 to 200 μm. The content of the aggregate in the substrate is preferably 65 to 99.5% by mass based on the total of the aggregate and the sintering aid for the substrate. Moreover, you may use what added shaping | molding binders, such as methylcellulose and polyethyleneglycol oleate, to the aggregate and the sintering aid for base | substrates.
The pore diameter of the porous body can be appropriately selected according to the purpose and application of the filter element 1.
The sintering aid for the substrate is used to reinforce the bond between the aggregates by firing together with the aggregates and form a strong porous body. Although the material is not particularly limited, for example, one or more of alumina, silica, zirconia, titania, glass frit, feldspar, cordierite, talc, gyrome clay, etc. can be used. Depending on the material, it can be appropriately selected. The average particle size of the sintering aid for the substrate is not particularly limited, but an average particle size of 5 μm or less is preferable. The content of the sintering aid for the substrate is preferably 0.5 to 35 mass% based on the total of the aggregate and the sintering aid for the substrate. Although the manufacturing method will be described in detail later, the porous filter element 1 can be formed by forming a clay containing such an aggregate and a sintering aid into an arbitrary shape and then firing it.
Further, the width of the groove 4 described above depends on the size of the filter element 1, but is preferably 0.3 to 3 mm in the case of the filter element 1 having a volume of 0.283L, for example. If the width of the groove 4 is less than 0.3 mm, the effect of increasing the water flow rate may not be obtained. If the width exceeds 3 mm, the mechanical strength of the filter element 1 is reduced, and the filter is removed from the groove 4. The element 1 may be damaged.
Similarly, the depth of the groove 4 varies depending on the size of the filter element 1, but for example, in the case of the filter element 1 having a volume of 0.283L, it is preferably 2 to 40 mm. If the depth of the groove 4 is less than 2 mm, the effect of increasing the water flow rate may not be obtained, and sealing is performed from the one end surface 6a side to a depth that does not reach the predetermined depth of the groove 4. It may be difficult to embed a material, and when it exceeds 40 mm, the mechanical strength of the filter element 1 may be reduced, and the filter element 1 may be damaged from the groove 4.
The sealing material 5 is embedded so as to form a gap of 1.0 to 20 mm from the bottom surface of the groove 4. In the filter element 1 of the present embodiment, the opening area of the outer peripheral surface of the through hole 7 is 0.3 to 117 mm. ² It is preferable that
The material of the sealing material 5 is not particularly limited. However, when the partition wall 8 or the like is made of ceramics, it is preferably ceramic from the viewpoint of strength and adhesiveness to the substrate. It is more preferable that the ceramic contains a component similar to a part of the components contained in the ceramic. Further, the material of the sealing material 5 is preferably a material with small shrinkage because cracks are likely to occur when the shrinkage is too large.
In the present embodiment, the filtration may be performed only with the porous body constituting the partition wall 8, but from the viewpoint of improving the separation performance while ensuring the processing speed, the partition wall having a relatively large pore diameter. It is preferable to use 8 as a porous substrate, and to form a filtration membrane 10 having a smaller pore diameter on the surface of the porous substrate. By setting it as such a structure, even if the average pore diameter of the filtration membrane 10 is made small, the pressure loss at the time of a raw | natural solution permeate | transmitting the inside of the filter element 1 can be suppressed. In this case, as shown in FIG. 2, it is preferable to form a filtration membrane 10 on the surface of the partition wall 8 that partitions the cell 9 in that the above object can be achieved efficiently. The average pore diameter of the filtration membrane 10 can be appropriately selected according to the use and purpose of the filter element 1, that is, the particle diameter of the foreign matter contained in the stock solution to be purified. For example, the filter element 1 of the present embodiment is selected. When used in a water purifier, the average pore diameter of the filtration membrane 10 is preferably about 0.1 to 2.0 μm, and more preferably about 0.2 to 0.7 μm.
The material of the filtration membrane 10 is not particularly limited, but preferably contains ceramic particles and a filtration membrane sintering aid. The ceramic particles are preferably used by selecting from the above-mentioned materials listed as preferable for the aggregate, and the average particle diameter is preferably about 0.1 to 10 μm. By selecting a smaller particle size, the pore size after calcination becomes smaller, so the particle size can be appropriately selected according to the purpose of filtration, for example, for use in a water purifier. In order to obtain a pore diameter in such a range, the average particle diameter of the ceramic particles is preferably about 0.2 to 5.0 μm, and more preferably about 0.4 to 2.5 μm. The filtration membrane sintering aid is also preferably selected from the materials listed as preferred for the substrate sintering aid. The ratio of the ceramic particles and the sintering aid for the filtration membrane is preferably 85 to 99.5% by mass of the ceramic particles based on the total of the ceramic particles and the sintering aid for the filtration membrane. The agent is preferably contained in an amount of 0.5 to 15% by mass. The filtration membrane 10 can be formed by applying these ceramic particles and a filtration membrane sintering aid in the form of a slurry to the substrate surface and then firing. Further, the filtration membrane 10 may be one layer, but may be two or more layers. In that case, the average pore diameter of the outermost filtration membrane 10 is minimized, and the pore diameters are increased in order toward the partition wall 8. It is preferable to enlarge it.
Further, in the present embodiment, the sealing material is provided at a portion of the other end 3b of the filter element 1 corresponding to the groove 4 in which the sealing material 5 is embedded in one end 3a. It is preferable that a clogging material 11 of the same material as 5 is provided. By comprising in this way, it can prevent that stock solution is discharged | emitted from the through-hole 7 without filtering.
Further, as shown in FIGS. 1A and 2, it is preferable that a seal layer 12 is formed on the surface including the end face 6 of at least one end 3 of the filter element 1. . By comprising in this way, when the filter element 1 has the filtration membrane 10 as mentioned above, it can prevent that the stock solution from the edge part 3 of the filter element in which the filtration membrane 10 is not formed permeate | transmits. Moreover, as shown in FIG. 3, when fixing the filter element 1 to a water purifier or the like, the end surface 6 where the stock solution flows or stays and the outer peripheral surface 2 where the purified water flows out are bonded with a packing 13 such as silicon or fluorine resin. When it is used and fixed in a liquid tight manner, its certainty can be increased.
The material of the seal layer 12 is not particularly limited, but when the filter element 1 is ceramic, it is preferably ceramic from the viewpoint of strength and adhesion to the substrate, and the partition wall 8 (FIG. 2). More preferably, it is a ceramic containing the same components as some of the components contained in (see). However, since it is required that the undiluted solution is not substantially permeated, it is necessary to use a glitz made of ceramics, such as a glitz, particularly silica and alumina as main components, and a fritted glaze containing 10% by mass or less of zirconia. Etc., and may contain methylcellulose as a binder.
The size of the filter element 1 of the present embodiment is not particularly limited, and can be any shape depending on the application / purpose, installation location, etc. For example, for a household water purifier. When used as the filter element 1, it is preferable that the end face has a cylindrical shape with a diameter of 50 to 100 mm and an axial length of 50 to 150 mm. Also, the size can be appropriately selected according to the processing amount, installation location, and the like.
The water flow rate of the filter element 1 is not particularly limited, but when used as the filter element 1 for a water purifier, the water flow rate at a water pressure of 0.1 MPa may be 3 to 30 L / min. preferable. Further, in the filter element 1 having an end face diameter of 62 mm, the axial length is preferably 7 to 13 L / min per 100 mm, and in the filter element 1 having an end face diameter of 90 mm, It is preferable that the axial length is 15 to 25 L / min per 100 mm. By comprising in this way, the filter element 1 of this Embodiment can fully satisfy the specification of the general water flow quantity of a domestic water purifier.
As shown in FIG. 1B, in this embodiment, the cell 9 of the filter element 1 has a circular cross-sectional shape. However, the present invention is not limited to this. In addition to an arbitrary polygon such as a triangle, a quadrangle, a pentagon, and a hexagon, the shape may be a circle, an ellipse, or a corrugated shape, but the strength of the partition wall 8 and the filtration membrane 10 and the filtration membrane 10 are uniform. It is preferable that it is circular shape or a substantially circular shape from a viewpoint which can be formed in a circle. Here, the substantially circular shape includes an elliptical shape, an oval shape, an oval shape, and the like, as well as a shape in which a vertex of a polygon is rounded. The size of the cross section of the cell 9 is not particularly limited. However, if the cross section is too small, the resistance during inflow of the stock solution may be too large. Conversely, if the cross section is too large, a sufficient filtration area can be obtained. It may disappear. The preferable range of the cross-sectional area of the cell 9 varies depending on the viscosity of the stock solution. For example, when the filter element 1 of the present embodiment is used in a water purifier, the range is 0.2 to 20 mm. ² Preferably, 0.5 to 10 mm ² More preferably. By setting it in such a range, it is easy to form a film even when forming the filtration membrane 10, and the area of the filtration membrane 10 per unit volume can be made relatively large, that is, the filter element 1 can be downsized. can do. Moreover, there is no restriction | limiting in particular in the number of cells 9, If it is an expert, it can select suitably from the relationship of intensity | strength, a magnitude | size, and a processing amount.
The arrangement state of the cells 9 included in the filter element 1 is not particularly limited. However, as the number of the cells 9 increases, the filtration membrane area can be increased, so that the water flow rate can be improved. Compactness is realized. As a preferable arrangement, the shape at the end face of the cells 9 is a circle, the centers of the cells 9 are connected, and the cells 9 are packed in a close-packed manner in an equilateral triangle arrangement. In this case, the thickness of the partition walls 8 between the cells 9 is preferably 5 to 30 times the average particle diameter constituting the porous body, or 0.1 to 1 times the diameter of the cells 9. If the thickness of the partition wall 8 is less than 5 times the average particle diameter constituting the porous body, the strength of the porous body may be too low to form the porous body. Close packing may not be possible. If the diameter of the cell 9 is less than 0.1 times, the strength of the porous body may be too low to be molded, and if it exceeds 1 time, the cell 9 may not be close-packed.
Next, an embodiment of the filter element manufacturing method of the present invention will be specifically described with reference to the drawings.
In the manufacturing method of the filter element manufacturing method of the present embodiment, as shown in FIG. 4, first, as shown in FIG. 4, a raw material is extruded and formed into a predetermined shape made of a porous body having cells 9 that serve as a flow path for the stock solution. A green filter molded body 20 is obtained. This raw material is composed of, for example, the above-mentioned preferred ratio of the aggregate selected from the above-mentioned preferred aggregate and the preferred sintering aid for the substrate and the sintering aid for the substrate (aggregate: sintering aid for the substrate = 65). ~ 95 mass%: 35 to 5 mass%), and a dispersion medium, an organic binder, and a surfactant and a plasticizer as necessary are added thereto, and kneaded using a kneader kneader or the like to form a clay. . This is extruded into a desired shape, for example, a cylindrical shape in the present embodiment, using, for example, a vacuum extrusion molding machine.
Next, the obtained green filter molded body 20 is dried and fired to obtain a fired filter molded body. As a drying method, for example, preliminary drying is performed for 15 minutes using a microwave oven or the like, and thereafter, drying is performed using a dryer so that the moisture of the green filter molded body 20 is 3% by mass or less.
When the filter element 1 to be manufactured (see FIG. 2) has the above-described filter membrane 10 (see FIG. 2), the unfired filter is formed. Before firing the body 20, as shown in FIG. 5, in the step of forming the filtration membrane 10 (see FIG. 2), the filtration membrane 10 (FIG. 2) is formed at the center and the outer periphery of the unfired filter molded body 20. And a predetermined depth from the end face side to the inside, and from one part of the edge of one end face along the predetermined cell 9 to the other part. Then, at least one provisional groove 21 extending substantially linearly is formed so as to maintain the diameter or the shape of the string in a circle. In the present embodiment, two temporary grooves 21 having a depth of 15 mm are formed. The temporary groove 21 can be easily formed using a disk-shaped cutter 22 or a metal saw (not shown). Moreover, when manufacturing the filter element which does not have the filtration membrane 10 (refer FIG. 2), you may abbreviate | omit this process.
Next, as shown in FIG. 6, a temporary sealing material 23 substantially the same as the above-described raw material is embedded in the temporary groove 21 of the green filter molded body 20. At this time, a plate-like member having a thickness approximately equal to the width of the temporary groove 21 so that the temporary sealing material 23 is embedded in a portion from one end face side to a depth not reaching the predetermined depth of the temporary groove 21. 24 is disposed in the temporary groove 21, and the temporary sealing material 23 is preferably pushed into one end face of the green filter molded body 20 using a spatula 25 or the like. Moreover, when the process of forming the temporary groove 21 is omitted as described above, this process may be omitted.
Next, the dried unfired filter molded body 20 is fired at a maximum temperature of 1000 to 1600 ° C. for 0.1 to 3 hours using, for example, alumina having an average particle diameter of 80 μm as the mesh sand, and the fired filter. A molded body is obtained.
Next, a filtration membrane 10 is formed on the obtained fired filter molded body. As described above, when manufacturing a filter element that does not have the filtration membrane 10 (see FIG. 2), this step may be omitted. The film forming process for forming the filtration membrane 10 (see FIG. 2) can be performed using a film forming apparatus using a dynamic pressure vacuum method as shown in FIG. 7, for example. Ceramic particles selected from among the above-mentioned preferred ceramic particles alone, or a sintering aid selected from the ceramic particles and the above-mentioned preferred sintering aid for filtration membranes can be used as a sintering aid for ceramic particles / filtration membranes. The film forming slurry 27 mixed at a mass ratio of preferably 75 to 99.5 / 25 to 0.5, more preferably 80 to 95/20 to 5 is prepared, and the fired filter molded body 28 is used as a filter. By filtering the film-forming slurry 27, the solid content of the film-forming slurry 27 is formed as a filtration film 10 (see FIG. 2) on the surface of the partition wall 8 (see FIG. 2). The film forming slurry 27 is caused to flow and circulate through the monolithic cell 9 (see FIG. 2), and the filtration membrane 10 (see FIG. 2) is formed on the surface of the partition wall 8 (see FIG. 2) with a predetermined thickness. The filtered water 29 is discharged in an amount equivalent to (surface area of the partition wall 8 (see FIG. 2) of the fired filter molded body 28 × thickness of the filtration membrane 10 (see FIG. 2) × density of the film-forming slurry 27). In addition, after the filtered water 29 is recovered, the fired filter molded body 28 is vacuum dehydrated from the filtered water side so that the shape of the formed filtration membrane 10 (see FIG. 2) is maintained. Thereafter, after drying the fired filter formed body 28 on which the filtration membrane 10 (see FIG. 2) is formed at 30 to 60 ° C., a predetermined temperature and time according to the selected ceramic particles and the sintering aid, For example, it is held at a maximum temperature of 900 to 1450 ° C. for about 0.1 to 3 hours and fired.
Next, the fired filter molded body 28 on which the filter membrane 10 (see FIG. 2) is formed has a predetermined length, in this embodiment, a diamond cutter or the like so that the length is 100 mm. As shown in FIG. 8, one end portion of the cut fired filter molded body 28 has a predetermined depth from the end surface side to the inside, and along the predetermined cell 9 array. A grooved filter molded body is formed by forming two grooves 4 extending substantially linearly so as to maintain a circular diameter or string shape from one part of the edge of one end surface to the other part. Get 30. The groove 4 can be easily formed using, for example, a groove processing machine 32 having a rotary blade 36 having a thickness of 0.6 mm. In addition, for example, when a V-shaped positioning jig 33 is used in the groove processing, positioning becomes easy.
The width of the groove 4 depends on the size of the filter element 1 to be manufactured (see FIG. 1A). For example, the filter element 1 having a volume of 0.283 L (FIG. 1A). Reference) is preferably 0.3 to 3.0 mm. If the width of the groove 4 is less than 0.3 mm, the effect of increasing the water flow rate may not be obtained. If the width exceeds 3 mm, the mechanical strength of the filter element 1 (see FIG. 1A) is increased. The filter element 1 (see FIG. 1A) may be damaged from the groove 4 due to the lowering.
Similarly, the depth of the groove 4 varies depending on the size of the filter element 1 (see FIG. 1A). For example, the filter element 1 having a volume of 0.283 L (FIG. 1A). In the case of producing a reference), it is preferably 2 to 40 mm. If the depth of the groove 4 is less than 2 mm, the effect of increasing the amount of water flow may not be obtained, and the sealing material is applied from one end face side to a depth that does not reach the predetermined depth of the groove 4. 5 (see FIG. 1 (a)) may be difficult to embed, and if it exceeds 40 mm, the mechanical strength of the filter element 1 (see FIG. 1 (a)) is reduced. The filter element 1 (see FIG. 1A) may be damaged.
Next, as shown in FIG. 9, among the grooves 4 of the obtained grooved filter molded body 30 (see FIG. 8), from one end face side to a depth not reaching the predetermined depth of the grooves 4. The sealing material 5 is embedded only in this portion, and the outer peripheral surface of the grooved filter molded body 30 (see FIG. 8) penetrates substantially linearly from one part to another part at a predetermined distance from one end face side. A filter molded body 31 with through holes having through holes 7 is obtained. The method of embedding the sealing material 5 can be performed in the same manner as the method of embedding the temporary sealing material 23 shown in FIG.
The sealing material 5 is preferably embedded so as to have a gap of 1.0 to 20 mm from the bottom surface of the groove 4. Moreover, there is no restriction | limiting in particular as a material of the sealing material 5, However, The substantially same thing as the raw material of the unbaking filter molded object 20 (refer FIG. 4) mentioned above can be used suitably.
At this time, the clogging material 11 made of the same material as that of the sealing material 5 (see FIG. 4) is formed at a portion corresponding to the groove 4 in which the sealing material is embedded at the other end. 2) may be provided.
Further, as shown in FIG. 10, the seal layer 12 may be formed on the surface including the end face of at least one of the end portions of the filter molded body 31 with a through hole. As the material of the seal layer 12, the above-described glaze and the like can be suitably used. As a method of forming the seal layer 12, a rotating jig 34 for rotating the filter molded body 31 with a through hole is used. Then, a liquid glaze or the like is applied in the form of a mist using the spray gun 25 while being rotated, and the applied glaze or the like is naturally dried to form the seal layer 12.
Next, the obtained filter-formed body 31 with through holes is fired for 0.1 to 3 hours at a maximum temperature of 900 to 1600 ° C. using alumina having an average particle diameter of 80 μm as the sand. The filter element 1 (see FIG. 1A) is obtained by firing again.
With such a configuration, a filter element that is small and excellent in water permeability and that is suitable for use in process equipment, water purifiers for household use, etc. in the fields of chemical industry, food industry, etc., can be easily and low-cost. Can be manufactured.
[0058]
EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples.
Example 1
As a raw material, 10% by mass of talc / gallome clay was added as a sintering aid to 90% by mass of alumina having an average particle size of 80 μm and a purity of 98% or more. 1 part by weight of polyethylene glycol oleate as a lubricant and 10 parts by weight of water as a lubricant were added and kneaded with a kneader to prepare a clay for extrusion.
Next, using a vacuum extrusion molding machine, a monolith-shaped green filter molded body having 499 cells having a diameter of 2 mm, an end face having a diameter of 62 mm, and a length of 1000 mm was extruded. After molding, preliminarily dry using a microwave oven for 15 minutes for the purpose of curing the methylcellulose and maintaining the shape, and then using a dryer so that the water content of the green filter molded body is 3% by mass or less. And dried at 80 ° C. for 16 hours.
Next, the edge of one end surface along a predetermined cell array as shown in FIG. 5 is formed so that the central portion and the outer peripheral portion of the green filter molded body are formed uniformly. A temporary groove having a width of 1 mm and a depth of 15 mm extending substantially linearly so as to maintain a circular diameter or string shape from one part to another part was formed.
Next, 20% by mass of alumina / zirconia-based glass as a sintering aid is added to the temporary groove of the fired filter molded body to 80% by mass of alumina having an average particle diameter of 80 μm and a purity of 98% or more. A temporary sealing material kneaded by adding 10 parts by mass of polyvinyl alcohol externally to the part was embedded. At this time, a plate-like member having a thickness approximately equal to the width of the temporary groove is provided so that the temporary sealing material is embedded in a portion from one end surface side to a depth not reaching the predetermined depth of the temporary groove. Arranged.
Next, the dried unfired filter molded body was fired at a maximum temperature of 1250 ° C. for 1 hour using alumina having an average particle diameter of 80 μm as the mesh sand to obtain a fired filter molded body.
Next, 10% by mass of alumina / zirconia glass as a sintering aid was added to 90% by mass of alumina having an average particle size of 2.5 μm and a purity of 98% or more, and the peptizer was added to 100 parts by mass in total. As shown in FIG. 7, 1.0 part by weight of ammonium polycarboxylate, 5 parts by weight of polysaccharide as a shape-retaining agent, and 90 parts by weight of water were added and stirred using a stirrer to prepare a film-forming slurry. The film was formed on the surface of the partition wall of the fired filter molded body so as to have a thickness of about 200 μm by using the film forming apparatus 26 using the pressurized vacuum method shown. After the filtration membrane was formed, the fired filter molded body was dried at 30 to 60 ° C., and then fired at 1000 ° C. for 1 hour using alumina having an average particle diameter of 80 μm as the mesh sand.
Next, the end portion is cut so that the length of the fired filter molded body becomes 100 mm, and a predetermined depth is formed from one end surface side to the inside at one end of the cut fired filter molded body. And two grooves having a width of 1 mm and a depth of 15 mm extending substantially linearly so as to maintain a circular diameter or chordal shape from one part of the edge of one end surface to the other part. It formed and the filter molded object with a groove | channel was obtained.
Next, among the grooves of the obtained grooved filter molded body, a sealing material is embedded only in a portion from one end surface side to a depth of 10 mm, and one of the outer peripheral surfaces of the grooved filter molded body is A filter molded body with a through hole having a through hole with a width of 1 × 10 mm penetrating almost linearly from one part separated from the end face side by a predetermined distance to another part was obtained. As the sealing material, 20% by mass of alumina / zirconia glass as a sintering aid is added to 80% by mass of alumina having an average particle diameter of 80 μm and a purity of 98% or more, and 10 to 20 polyvinyl alcohol is added to 100 parts by mass in total. What knead | mixed by adding a mass part was embedded using the method similar to a temporary sealing material. Further, a clogging material made of the same material as that of the sealing material was disposed at a portion corresponding to the groove portion in which the sealing material at one end portion was embedded in the other end portion of the filter molded body with the groove.
Further, on the surface including the end face of both ends of the grooved filter molded body, an alumina / zirconia glass and a 2% by weight aqueous solution of methylcellulose as a binder are mixed so that the mass ratio is the same. As shown in FIG. 9, while rotating the grooved filter molded body, the glaze slurry was applied in the form of a mist using a spray gun, and the applied glaze was naturally dried to form a seal layer. .
Next, the obtained filter molded body with through-holes was fired again at a maximum temperature of 1000 ° C. for 1 hour, for example, using alumina having an average particle diameter of 80 μm as the mesh sand, and the filter element was fired again. Obtained.
Pure water was allowed to flow for 1 minute from one end face side, which becomes the inlet of the obtained filter element (Example 1), under conditions of a water pressure of 0.1 MPa and a temperature of 20 ° C., and the water flow rate (L / min) Was measured. The measurement results are shown in Table 1.
[0070]
[Table 1]

Examples 2 and 3
A filter element (Example 2) configured in the same manner as in Example 1 except that three through holes are formed, and a filter element (Example in Example) configured in the same manner as in Example 1 except that four through holes are formed. 3) was prepared in the same manner as described above. From one end face side that becomes the inlet of the obtained filter element (Examples 2 and 3), pure water was allowed to flow for 1 minute under conditions of a water pressure of 0.1 MPa and a temperature of 20 ° C., and the water flow rate (L / min) was It was measured. The measurement results are shown in Table 1.
(Comparative Example 1)
Using the same material as in Example 1, a filter element (Comparative Example 1) was manufactured without forming a through hole. Pure water was allowed to flow for 1 minute under the conditions of a water pressure of 0.1 MPa and a temperature of 20 ° C. from one end face side serving as an inlet of the obtained filter element (Comparative Example 1), and the water flow rate (L / min) was measured. . The measurement results are shown in Table 1.
As shown in Table 1, the filter element having the through holes (Examples 1 to 3) had a larger water flow rate than the filter element having no through hole (Comparative Example 1).
[0074]
As described above, according to the present invention, the present invention provides a filter element that is small and excellent in water permeability, and that is particularly suitable for use in process equipment and household water purifiers in fields such as the chemical industry and the food industry. A manufacturing method thereof can be provided.
[Brief description of the drawings]
FIG. 1 is a plan view schematically showing one embodiment of a filter element of the present invention, wherein (a) is a plan view from the side surface side, and (b) is a plan view from one end surface side. Show.
FIG. 2 is a sectional view schematically showing one embodiment of a filter element of the present invention.
FIG. 3 is a plan view schematically showing one embodiment of a filter element of the present invention.
FIG. 4 is a perspective view schematically showing an unfired filter molded body obtained in an embodiment of a method for producing a filter element of the present invention.
FIG. 5 is a perspective view showing a process of forming a temporary groove in an unfired filter molded body in one embodiment of the method for manufacturing a filter element of the present invention.
FIG. 6 is a perspective view showing a step of embedding a temporary sealing material in an unfired filter molded body in an embodiment of the method for producing a filter element of the present invention.
FIG. 7 is an explanatory view schematically showing a configuration of a film forming apparatus used in one embodiment of a filter element manufacturing method of the present invention.
FIG. 8 is a perspective view showing a step of forming a groove in a fired filter molded body in one embodiment of the filter element manufacturing method of the present invention.
FIG. 9 is a perspective view schematically showing a filter molded body with through holes obtained in an embodiment of a method for producing a filter element of the present invention.
FIG. 10 is a perspective view showing a step of forming a seal layer on a filter molded body with a through hole in one embodiment of a method for producing a filter element of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Filter element, 2 ... Outer peripheral surface, 3 ... End part, 3a ... One end part, 3b ... Other end part, 4 ... Groove, 5 ... Sealing material, 6 ... End face, 6a ... One end face, 7 DESCRIPTION OF SYMBOLS ... Through-hole, 8 ... Partition, 9 ... Cell, 10 ... Filtration membrane, 11 ... Sealing material, 12 ... Sealing layer, 13 ... Packing, 20 ... Unbaked filter molded object, 21 ... Temporary groove, 22 ... Disc shape Cutter, 23 ... Temporary sealing material, 24 ... Plate-like member, 25 ... Spatula, 26 ... Film forming apparatus, 27 ... Film forming slurry, 28 ... Firing filter molded body, 29 ... Filter water, 30 ... Grooved filter molded body 31 ... Filter molded body with through-holes, 32 ... Groove processing machine, 33 ... Positioning jig, 34 ... Rotating jig, 35 ... Spray gun, 36 ... Rotating blade.

Claims

Predetermined consisting of a porous body having a plurality of cells serving as a flow path for the stock solution, the stock solution to be purified taken in from one end of the stock solution being purified by permeating through the inside, and being taken out as a purified solution from the outer peripheral surface side A filter element having a shape,
The one end portion has a predetermined depth from the end face side toward the inside, and substantially extends from one part of the edge of the one end face to another part along the predetermined cell array. At least one groove extending linearly is formed, and a sealing material is embedded in a portion of the groove from the one end face side to a depth not reaching the predetermined depth of the groove. The groove and the sealing material form a through-hole penetrating substantially linearly from one part to the other part of the outer peripheral surface at a predetermined distance from the one end face side. A filter element.

The clogging material of the same material as the sealing material is disposed at a portion of the other end portion corresponding to the groove portion in which the sealing material is embedded in the one end portion. Filter element as described in.

The filter element according to claim 1 or 2, wherein a seal layer is formed on a surface including the end face of at least one of the end portions.

The filter element according to any one of claims 1 to 3, wherein the end face has a cylindrical shape with a diameter of 50 to 100 mm and an axial length of 50 to 150 mm.

It is a filter element for water purifiers, The filter element as described in any one of Claims 1-4.

The filter element according to claim 5, wherein the water flow rate at a water pressure of 0.1 MPa is 3 to 30 L / min.

A raw filter molded body having a predetermined shape made of a porous body having cells that serve as a flow path for the stock solution by extruding the raw material,
The obtained green filter molded body was dried and fired to obtain a fired filter molded body,
One end portion of the obtained fired filter molded body has a predetermined depth from the end surface side toward the inside, and one part of the edge of the one end surface along the predetermined cell array To form at least one groove over the other part to obtain a grooved filter molded body,
Of the groove of the obtained filter molded body with the groove, a sealing material is embedded only in a portion from the one end face side to a depth not reaching the predetermined depth of the groove, and the grooved filter molded body is obtained. Obtaining a filter molded body with a through-hole having a through-hole penetrating substantially linearly from one part separated from the one end face side to the other part of the outer peripheral surface of
A filter element manufacturing method, wherein the obtained filter molded body with through holes is fired again to obtain a filter element.

A step of disposing a clogging material of the same material as that of the sealing material in a portion corresponding to the groove portion in which the sealing material is embedded in the one end portion of the other end portion. A method for producing the filter element according to claim 7.

The method for manufacturing a filter element according to claim 7 or 8, further comprising a step of forming a seal layer on a surface including the end face of at least one of the end portions.