JP3817061B2 - Structure, manufacturing method thereof, and manufacturing apparatus thereof - Google Patents

Description

【００１９】
これらの組み合わせの中でも、（１）粉体が接着性粉体以外の粉体のみからなる場合、多孔性基材が絶縁性又は半導電性で、粉体が半導電性の組み合わせ、（２）粉体として接着性粉体と接着性粉体以外の粉体を含む場合、多孔性基材の種類に関わらず、接着性粉体と接着性粉体以外の粉体のいずれか一方の粉体が半導電性の組み合わせ、であるのが好ましい。このような組み合わせとすることにより、適度な導電性が得られ、付着した粉体が電荷を蓄積しすぎないため、粉体の付着量を多くすることができる。
【００２０】
本発明の第１構造体は上述のような多孔性基材と粉体とを含み、この粉体が多孔性基材構成材の表面全体に付着した状態にある。この「多孔性基材構成材の表面全体」とは多孔性基材を構成する材料の表面全体であることを意味し、例えば、多孔性基材が不織布などのように繊維からなる場合には、全部の繊維の表面全体（つまり、不織布などの厚さがある場合には不織布内部における繊維の表面も含む）を意味する。
【００２１】
なお、粉体は外観上、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着している。このように、粉体同士が密着した状態にはなく、処理流体などとの接触が容易であるため、粉体の機能を十分に発揮することができる。また、処理流体が第１構造体を通過する場合には通過抵抗の低いものである。この粉体の密充填時に形成される微細孔とは、粉体を粉体同士が最も密着するように二次元的に配列させた時に形成される微細孔をいい、例えば、粉体形状が球状である場合には、粉体を千鳥状に配列させた時に隣接する２つの粉体間で形成される微細孔をいう。なお、粉体は一定形状及び一定の大きさを有する訳ではないため、この「密充填時に形成される微細孔」は次のようにして測定することができる。まず、粉体を適当な溶媒中に分散させ、この分散液をガラス板などの基材上にキャスティングする。なお、この溶媒としては、粉体が疎水性である場合には、アルコールなどの有機溶媒を使用し、粉体が親水性である場合には、水などを使用する。また、粉体が疎水性であるか親水性であるかを問わず、適当な界面活性剤を含む水を使用することができる。つまり、粉体との親和性に優れる溶媒を使用する。次いで、基材上の粉体を乾燥固化させる。そして、乾燥固化した粉体の顕微鏡写真を撮り、この顕微鏡写真から微細孔を測定する。なお、本発明における微細孔（例えば、粉体の密充填時に形成される微細孔や、第１構造体の粉体の付着により形成される微細孔など）の大きさは、微細孔の面積と同じ面積を有する円の直径とする。
【００２２】
なお、「外観上」とは第１構造体を外側から二次元的に（例えば、顕微鏡により）観察した状態をいい、第１構造体をどの方向から観察しても良い。例えば、不織布に粉体が付着した第１構造体の場合、第１構造体の厚さ方向と同じ方向から観察しても良いし、第１構造体の厚さ方向に対して直角方向から観察しても良い。なお、第１構造体は少なくとも２方向から観察し、いずれの方向から観察した場合にも、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着しているのが好ましい。例えば、第１構造体が不織布に粉体が付着したものからなる場合、第１構造体の厚さ方向と同じ方向から観察した場合と、第１構造体の厚さ方向に対して直角方向から観察した場合の両方の場合に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で粉体が多孔性基材に付着しているのが好ましい。このような状態にあると、より粉体同士の密着性が低く、処理流体などとの接触が容易で、粉体の機能をより一層発揮することができる。
【００２３】
本発明の第１構造体の粉体によって形成される微細孔９は、略同程度（図１参照）の大きさのものが分散していても良いし、大小様々な大きさの微細孔９（図２参照）が混在していても良い。
【００２４】
本発明の別の構造体（以下、「第２構造体」と称することがある）は、外観上、粉体が粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で凝集していることにより、所定形状が形成されており、しかも粉体の凝集によって中空状態が形成されたものである。この第２構造体も前述の第１構造体と同様に、外観上、粉体が粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態にあり、粉体同士が密着した状態にはないため、粉体の機能を十分に発揮することができ、しかも処理流体が第２構造体を通過する場合には通過抵抗の低いものである。特に、第２構造体は粉体の凝集によって中空状態が形成されており、粉体の作用可能な表面積がより広いため、粉体の機能をより一層発揮することができ、処理流体が第２構造体を通過する場合には、より一層通過抵抗の低いものである。
【００２５】
この第２構造体の前述の第１構造体との相違点は（１）粉体が凝集していることにより所定形状が形成されている点、及び（２）粉体の凝集によって中空状態が形成されている点、のみが相違する。つまり、多孔性基材を含んでいない点のみが相違する。この相違点以外は前述の第１構造体と全く同じであるため、これら相違点についてのみ説明する。
【００２６】
まず、（１）粉体が凝集していることにより形成される形状としては、特に限定されるものではないが、例えば、シート（例えば、不織布、織物、編物、これらの複合体など）の形状、シートをジグザグ状に折り加工した形状、ハニカム形状、シートを丸めて筒状とした形状、シートをジグザグ状に折り加工したものを丸めて筒状とした形状、シートを袋状に加工した形状などがある。
【００２７】
次いで、（２）粉体の凝集によって中空状態が形成されているとは、第２構造体を任意の方向から裁断した場合に、粉体により輪郭が形成され、その輪郭の内側には粉体が存在しない状態をいう。
【００２８】
このように、本発明の第１及び第２構造体は粉体の機能を十分に発揮することができ、しかも処理流体が第１又は第２構造体を通過する場合には通過抵抗の低いものであるため、気体フィルタ（例えば、脱臭フィルタ、特定ガス状物質の除去フィルタ、排気ガスやオゾンなどの分解フィルタ、光触媒などの触媒担持フィルタなど）、液体フィルタ（例えば、水浄化フィルタ、純水製造フィルタなど）、或いは微生物担体などとして、好適に使用できる。
【００２９】
本発明の第１構造体は、例えば次のようにして製造することができる。
【００３０】
粉体を単極性に帯電させた後、帯電した粉体に対して気流及び電界を作用させて、所定形状を有する多孔性基材へ供給し、多孔性基材構成材の表面全体に、外観上、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着させることにより、本発明の第１構造体を製造することができる。このように粉体には気流が作用して多孔性基材へ供給され、強制的に多孔性基材全体、つまり多孔性基材の内部及び裏面まで到達するため、多孔性基材構成材の表面全体に付着する。また、粉体は単極性に帯電しており、しかも電界も作用しているため、多孔性基材との間に働く静電引力によって多孔性基材構成材の表面全体に付着しやすいばかりでなく、粉体間には反発力が作用するため、粉体は粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で、一部に偏在（例えば、繊維同士の交差点）することなく、多孔性基材構成材の表面全体に付着する。なお、このような方法により第１構造体を製造すると、気流の通気抵抗を利用することにより、粉体の付着量を監視することが容易であったり、所望の通気抵抗を有する第１構造体を容易に製造できるという効果も奏する。
【００３１】
この粉体を単極性に帯電させる方法としては、例えば、直流コロナ放電、沿面コロナ放電（交流コロナ放電）、Ｘ線荷電、摩擦荷電などを利用できる。これらの中でもＸ線荷電であると、（１）粉体がＸ線発生装置に付着しにくい、（２）帯電空間４の電界強度を強くすることができる、（３）オゾンなど有害ガスを発生しにくい、などの利点がある。
【００３２】
なお、極性は特に限定されるものではなく、正極性であっても負極性であっても良く、また、正極性と負極性を交互に作用させても良い。また、この帯電は粉体全体を帯電できるように、粉体を気体中（好適には空気中）に供給し、個々の粉体に分散させた状態で帯電させるのが好ましい。
【００３３】
次いで、帯電した粉体に対して気流を作用させて多孔性基材へ供給する。この気流はどのような気流であっても良いが、引火などの危険性がなく、取り扱いやすい空気を使用するのが好ましい。また、気流の多孔性基材における通過速度は多孔性基材の種類、多孔性基材の大きさ、多孔性基材の荷電状態などによって変化するため限定することはできないが、１０〜２００ｃｍ／秒程度であるのが好ましい。なお、気体の多孔性基材における通過速度は一定であっても、規則的に又は不規則的に変化させても良いが、通過速度を変化させることにより、多孔性基材の部位（例えば、多孔性基材が不織布からなる場合の厚さ方向）によって、粉体の付着量を変化させることも可能である。更に、多孔性基材構成材料の表面全体に粉体が付着するように、多孔性基材への粉体の供給側とは反対側から気体を吸引するのが好ましい。
【００３４】
また、粉体の多孔性基材への供給は１度である必要はなく、２度以上、同じ方向から或いは違う方向から供給することができる。例えば、多孔性基材が不織布からなる場合、不織布の両面から粉体を供給すると、不織布構成繊維の表面全体により均一に付着した第１構造体を製造することができる。なお、このように不織布の両面から粉体を供給する場合、１度粉体を供給して付着した粉体が２度目の粉体の供給により脱落することがないように、粉体同士及び粉体と繊維とを接着した後に２度目の粉体を供給するのが好ましい。また、１度目に供給する粉体と２度目以降に供給する粉体とは同じであっても異なっていても良い。
【００３５】
本発明においては、前述のような気流の作用以外に電界を作用させているため、多孔性基材との間に働く静電引力によって、多孔性基材構成材の表面全体に粉体を付着させることができる。この帯電した粉体に作用させる電界強度は、多孔性基材の種類、多孔性基材の大きさ、多孔性基材の荷電状態などによって変化するため限定することはできないが、１００〜５，０００Ｖ／ｃｍ程度であるのが好ましい。
【００３６】
帯電した粉体の多孔性基材への供給方向としては、気流が通過しやすい方向からであるのが好ましく、例えば、多孔性基材が不織布からなる場合には、不織布の厚さ方向と同じ方向から供給するのが好ましく、多孔性基材がハニカム状の場合には、ハニカムのセルの長さ方向と同じ方向から供給するのが好ましい。
【００３７】
更に、多孔性基材が導電性材料から構成されたハニカム構造を有する場合、電界集中を生じ、帯電した粉体は粉体の供給方向側の表面近傍に堆積しやすい傾向がある。この場合、ハニカムの目開きと実質的に同じ目開き（形及び大きさ）の絶縁物を、ハニカム構造を有する多孔性基材の粉体供給方向側の上方に配置して、上記の傾向を防止することができる。なお、絶縁物の厚さは０．１〜２ｍｍ程度で十分である。
【００３８】
本発明の別の第１構造体の製造方法（以下、「第２製造方法」ということがある）は、粉体を単極性に帯電させた後、帯電した粉体を気流の作用により、接地された支持体上に載置された所定形状を有する多孔性基材へ供給し、多孔性基材構成材の表面全体に、外観上、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着させる方法である。この第２製造方法と前述の製造方法（以下、「第１製造方法」ということがある）とは、帯電した粉体に対して電界を作用させる代わりに、接地された支持体上に多孔性基材を載置している点のみが相違する。この第２製造方法のように、接地された支持体上に多孔性基材を載置した場合、気流によって供給される粉体の電荷によって支持体との間に電位差が生じ、前述の第１製造方法の場合と同様に、電界を有する状態となるため、原理的には第１製造方法と同じである。
【００３９】
この第２製造方法で使用できる支持体としては、帯電した粉体と支持体との間に電位差が生じるように、導電性（比抵抗：１０⁰Ω・ｃｍ未満）から半導電性（比抵抗：１０⁰〜１０⁹Ω・ｃｍ）の材料からなるものを使用することができる。また、気流の流れを妨げないように、ネットや多孔板などの多孔性のものを使用するのが好ましい。
【００４０】
本発明の第１構造体は例えば上述のような方法により製造することができるが、上述のような方法により製造した第１構造体は多孔性基材表面に粉体が静電気的に付着しているだけで、振動や摩擦などによって脱落する場合があるため、付着した粉体を固定するのが好ましい。この固定方法としては、例えば、粉体として接着性粉体を含んでいる場合には、接着性粉体を接着させるための接着処理がある。なお、接着性粉体が熱により接着可能なものである場合には、接着性粉体の形状を維持できる程度の温度で熱処理を実施するのが好ましいが、接着性粉体が完全に溶融する温度で熱処理を実施して、より小さい微細孔（しかし粉体の密充填時に形成される微細孔よりも大きい）を有する状態で粉体が付着した第１構造体を製造することもできる。
【００４１】
本発明の第２構造体は、例えば、上述のようにして粉体を付着させた第１構造体の粉体の固定及び多孔性基材を除去することにより製造することができる。この粉体を固定及び除去する手段としては、例えば、焼結する方法や、前述のような方法により粉体を固定した後に多孔性基材のみを溶媒などによって抽出する方法などがある。
【００４２】
焼結した場合、粉体同士が結合して固定される一方、多孔性基材は粉体によって形成された微細孔から揮発して、多孔性基材を除去することができる。そのため、焼結により製造された第２構造体においては、粉体以外に多孔性基材の残骸を含んでいる場合がある。また、このような方法により第２構造体を製造するには、粉体が焼結できるものであり、かつ多孔性基材が揮発できる（例えば、有機成分からなる）必要がある。
【００４３】
他方、前述のような方法により粉体を固定した後に、多孔性基材のみを溶媒などによって抽出する方法により製造された第２構造体においては、ほぼ粉体のみから構成される。また、このような方法により第２構造体を製造するには、多孔性基材を抽出する際に使用する溶媒によって抽出されない粉体を使用する必要がある。
【００４４】
本発明の製造装置は（１）粉体の供給手段、（２）粉体を単極性に帯電させる手段、（３）帯電した粉体に対して気流を作用させて多孔性基材へ供給できる手段、（４）帯電した粉体に対して電界を作用させて多孔性基材へ供給できる手段、とを含んでいるため、上述の第１製造方法を実施して、容易に第１構造体を製造することができる。
【００４５】
本発明の製造装置について、製造装置の模式的断面図である図３をもとに説明する。粉体の供給装置１は粉体を帯電空間４へ供給できる装置であり、帯電空間４へ供給する粉体の量を調整する働きをする。この供給装置１により供給される粉体量は帯電空間４の電界強度、粉体の付着量、多孔性基材６の種類などによって適宜設定される。なお、この供給装置１はどのような位置に設置しても良く、また２台以上設置しても良い。供給装置１を２台以上設置すると、配合の異なる粉体を交互に供給することができる。
【００４６】
分散装置２は供給装置１から供給された粉体を個々の粉体となるように分離かつ分散させ、後工程である帯電空間４における粉体の帯電処理を効率的に実施できるように設置している。なお、２種類以上の粉体を混合した場合（例えば、機能性粉体と接着性粉体とを含む場合）には、これらの粉体を混合する作用も有する。
【００４７】
気流発生装置３は供給装置１及び／又は分散装置２とつながれ（図３においては分散装置２に接続）、主として粉体を帯電空間４へ供給するための気流を供給する働きをし、補助的に多孔性基材６へ粉体を供給する働きをする。
【００４８】
帯電装置５は帯電空間４へ供給された粉体を単極性に帯電する作用をする。この帯電装置５としては、例えば、直流コロナ放電装置、沿面コロナ放電装置（交流コロナ放電装置）（図３）、Ｘ線発生装置、摩擦荷電装置などを利用できる。なお、極性は特に限定されるものではなく、正極性であっても負極性であっても良く、或いは両極性に交互に帯電しても良い。なお、図３においては、１つの帯電装置５により支持体７との間にも電圧を印加して電界を形成している。この電界の強度は特に限定するものではないが、１００〜５，０００Ｖ／ｃｍ程度であるのが好ましい。
【００４９】
なお、帯電空間４は粉体の飛散を抑制し、効率的に粉体を付着させることができるように、容器内に形成するのが好ましい。この容器は密閉された容器であっても開放された容器であっても良いが、後述の吸引装置８により気流の流量を制御する場合には、開放された容器であるのが好ましい。この開放された部分は容器のどの部分にあっても良いが、粉体の帯電空間４への供給部周辺、及び粉体の帯電空間４への供給部よりも帯電装置５側にあるのが好ましい。
【００５０】
上述のような帯電装置５によって帯電された粉体は、気流の下流側に配置されたシート状多孔性基材６の構成材の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着する。これは、後述の吸引装置８により発生させた気流によって、粉体が多孔性基材構成材の全体へ供給されること、及び上述の帯電装置５によって形成された電界により、多孔性基材との間に静電引力が働き、多孔性基材構成材の表面全体に付着しやすいばかりでなく、粉体間に反発力が作用するためである。特に多孔性基材が抵抗の低い（半導電性又は導電性）材料からなる場合、イオン流の作用によって、効率的に粉体を付着させることができる。
【００５１】
粉体はシート状多孔性基材６に対して任意の方向から供給できるように、シート状多孔性基材６の配置を変化させることができるのが好ましい。また、シート状多孔性基材６は気流が通過できるように、多孔性の支持体７により支持されているのが好ましい。なお、図３においては、支持体７と帯電装置５との間に電界を発生させているため、導電性の支持体７を使用している。
【００５２】
吸引装置８は吸引することによって気流を発生させ、（１）帯電した粉体を多孔性基材６へ供給する作用、（２）粉体をシート状多孔性基材６の内部まで侵入させる作用、（３）シート状多孔性基材６構成材の表面に付着しなかった粉体を回収する作用、などを有する。この気流の多孔性基材６における通過速度は、多孔性基材６の種類、多孔性基材６の大きさ、多孔性基材６の荷電状態などによって異なるが、１０〜２００ｃｍ／秒程度で通過できるように吸引するのが好ましい。なお、気体の多孔性基材６における通過速度は一定であっても、規則的に又は不規則的に変化させても良い。
【００５３】
図４は本発明の別の製造装置の模式的断面図であり、図３の製造装置とは（１）帯電装置５として直流コロナ放電装置を使用している点、及び（２）多孔性基材６としてハニカム構造からなるものを使用している点のみが相違するが、このような製造装置であっても、多孔性基材６の構成材の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着させることができる。特に多孔性基材が抵抗の低い（半導電性又は導電性）材料からなる場合、イオン流の作用によって、効率的に粉体を付着させることができる。
【００５４】
このように、帯電装置５としては粉体を単極性に帯電できるのであれば、どのようなものであっても使用することができる。また、多孔性基材６も特に限定されることなく粉体を付着させることができる。なお、ハニカム構造からなる多孔性基材の場合、セルの長さ方向と同じ方向から粉体を供給するのが好ましい。
【００５５】
また、多孔性基材６が導電性材料から構成されたハニカム構造を有するものである場合、電界集中を生じ、帯電した粉体は多孔性基材６の粉体供給方向側の表面近傍に堆積しやすい傾向がある。この場合、ハニカムの目開きと実質的に同じ目開き（形及び大きさ）の絶縁物を、ハニカム構造を有する多孔性基材６の粉体供給方向側の上方に配置して、上記のような傾向を防止することができる。なお、絶縁物の厚さは０．１〜２ｍｍ程度で十分である。
【００５６】
図５は本発明の更に別の製造装置の模式的断面図であり、図３の製造装置とは（１）気流発生装置３が供給装置１と接続されている点、（２）気流発生装置３による帯電空間４への粉体の供給方向が、多孔性基材６に対して対向方向である点、（３）粉体を帯電させるための電界を発生させる帯電装置５と、帯電した粉体を多孔性基材６に付着させるための電界とを発生させる電界発生装置５’とを具備し、電界を別々に発生させている点、が相違するが、この製造装置であっても、多孔性基材６の構成材の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着させることができる。
【００５７】
このように、気流発生装置３は供給装置１と接続されていても良いし、分散装置２と接続されていても良いし、両方に接続されていても良い。また、帯電空間４への粉体の供給はどの方向からでも良い。更に、粉体を帯電させるための電界と、帯電した粉体を多孔性基材６に付着させるための電界とが同じ電界であっても良いし、それぞれ独立した電界であっても良い。
【００５８】
なお、図５における製造装置における、帯電した粉体を多孔性基材６に付着させるための電界を発生させる電界発生装置５’は、多孔性基材６に強い電界を作用させることができるように、気流上流側の電極５’ａと気流下流側の電極５’ｂ（支持体７）との距離は短い方が好ましい。但し、気流上流側の電極５’ａと多孔性基材６とを接触させると、その接触した領域に粉体が付着するのが困難となるため、接触させないのが好ましい。また、気流上流側の電極５’ａ上に粉体が付着しにくいように、気流上流側の電極５’ａの極性と粉体の極性とを同じにするのが好ましい。図５の製造装置の場合、気流上流側の電極５’ａの極性は正極性であるため、帯電装置５により粉体を正極性に帯電するのが好ましい。
【００５９】
図６は本発明の更に別の製造装置の模式的断面図であり、図３の製造装置とは（１）帯電装置５としてＸ線発生装置を使用している点、（２）Ｘ線発生装置から発生したイオンから単極性のイオンのみを引き出し、粉体を帯電させるとともに、帯電した粉体を多孔性基材６に付着させるための電界も発生させる電界発生装置５’を具備している点が相違するが、この製造装置であっても、多孔性基材６の構成材の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着させることができる。特に多孔性基材が抵抗の低い（半導電性）材料からなる場合、イオン流の作用によって、効率的に粉体を付着させることができる。
【００６０】
図６におけるＸ線発生装置は（１）粉体がＸ線発生装置に付着しにくい、（２）帯電空間４の電界強度を強くすることができる、（３）オゾンなど有害ガスを発生しにくい、などの利点がある。
【００６１】
また、このＸ線発生装置はどこに配置しても良いが、効率的に粉体を帯電できるように、粉体が供給される領域近傍に設置するのが好ましい（図６においては容器の天井部の外側に設置）。更に、図６における態様のように、気流上流側の電極５’ａよりも上流側（多孔性基材に対して）にＸ線発生装置を設置する場合には、気流上流側の電極５’ａとして、ネットや多孔板などの多孔性のものや、非多孔性である場合には厚さの薄いものを使用するのが好ましい。
【００６２】
本発明の別の製造装置（以下、「第２製造装置」ということがある）は（１）粉体の供給手段、（２）粉体を単極性に帯電させる手段、（３）帯電した粉体に対して気流を作用させて多孔性基材へ供給できる手段、（４）多孔性基材を支持できる接地された支持手段、とを含んでいるため、前述の第２製造方法を実施して、容易に第１構造体を製造することができる。この第２製造装置は直接的に電界を発生させる手段がない代わりに、接地された支持手段を有する点のみが前述の製造装置（以下、「第１製造装置」ということがある）と相違する（図７参照）。この第２製造装置においては、気流によって供給される粉体の電荷によって設置された支持体との間に電位差が生じ、前述の第１製造装置の場合と同様に、電界を作用させた状態となるため、前述の第１製造装置と同様に、多孔性基材６の構成材の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で、粉体を多孔性基材に付着させることができる。
【００６３】
この第２製造装置で使用できる支持体としては、帯電した粉体と支持体との間に電位差が生じるように、導電性（比抵抗：１０⁰Ω・ｃｍ未満）から半導電性（比抵抗：１０⁰〜１０⁹Ω・ｃｍ）の材料からなるものを使用することができる。また、気流の流れを妨げないように、ネットや多孔板などの多孔性のものを使用するのが好ましい。
【００６４】
本発明の第１構造体は例えば上述のような製造装置により製造することができるが、上述のような製造装置により製造した第１構造体は多孔性基材表面に粉体が静電気的に付着しているだけで、振動や摩擦などによって脱落する場合があるため、第１製造装置及び第２製造装置は付着した粉体を固定する手段を備えているのが好ましい。この固定手段は微細孔を塞がないように、無圧下で実施できる手段であるのが好ましく、例えば、無風又は熱風により熱処理できる装置を使用できる。
【００６５】
また、本発明の第１及び第２製造装置は第２構造体を製造できるように、粉体を固定及び多孔性基材を除去できる手段を備えているのが好ましい。この手段としては、例えば、公知の焼結炉や、多孔性基材を抽出できる溶媒を保持した浴などがある。
【００６６】
以下に、本発明の実施例を記載するが、本発明は以下の実施例に限定されるものではない。
【００６７】
【実施例】
（実施例１）
多孔性基材６として、繊維径５５．４μｍのポリエステル繊維からなり、面密度７０ｇ／ｍ²、厚さ５ｍｍ、平均孔径０．５ｍｍ、１００ｍｍ角の不織布を用意した。また、粉体として、１５０メッシュパス（平均粒径：約２５μｍ（体積分布）、クラレ製、クラレコールＰＫ−Ｗ５）で不定形の活性炭と、平均粒径３μｍで球状のポリエチレン樹脂粉体（接着性粉体）とを用意した。
【００６８】
次いで、気流発生装置が供給装置１に接続されていること、及び容器の開口部が分散装置２からのびるノズルの周囲にのみ有すること以外は、図３と同じ第１製造装置により第１構造体を製造した。この条件は次の通りである。
（１）活性炭とポリエチレン樹脂粉体とを体積比３：２で供給装置１（三協パイオテク（株）製、マイクロフィーダーＭＦＨＶ−ＩＶＯ）にセットした後、気流発生装置３（エアコンプレッサー）から空気流（５Ｌ／分）を供給装置１へ供給して、粉体を分散装置２（三協パイオテク（株）製、マイクロフィーダーＭＦＨＶ−ＩＶＯ）へ供給（０．５３ｇ／分）し、分散装置２により個々の粉体となるように分散及び混合した。
（２）分散装置２により分散及び混合された粉体を、ノズル（直径３ｍｍ）から速度１１．８ｍ／秒で帯電空間４へ供給した。なお、供給速度は一定とした。また、直流電界（後述）に対して直角方向から粉体を供給した。更に、活性炭は分散装置により平均粒径が１０μｍ程度となるまで粉砕された後に、帯電空間４へ供給された。
（３）帯電空間４は容器（たて１４ｃｍ、よこ１４ｃｍ、高さ１５ｃｍ）に形成した。この容器は分散装置２から粉体を供給するノズル周囲に開口部を有するものを使用した。
（４）帯電空間４には帯電装置５によりプラスイオンのみを発生させた。この帯電装置５はアルミナ板（厚さ：２ｍｍ）の片面に線径５０μｍのワイヤー（放電電極）を１ｃｍ間隔で装着し、反対面にステンレス板（誘起電極）を装着したものを使用した。なお、それぞれの電極に周波数４０ＫＨｚ、電力５０ワットの交流を印荷して沿面放電を発生させた。また、帯電装置５とステンレス製メッシュ状支持体７（目開き１ｍｍ、線径０．５ｍｍ）との間に電位差を設けて直流電界（電界強度５ＫＶ／１５ｃｍ）を発生させた。
（５）多孔性基材６（不織布）は厚さ方向が直流電界の方向と一致するように、前記支持体７上に載置した。なお、粉体は不織布の片面側から１度付着させ、温度１０４℃の炉により１時間熱処理して、粉体同士及び粉体と不織布とを焼結した後、不織布を裏返して、最初の粉体供給面とは反対側から再度粉体を付着させた。そして、同じ条件で粉体を焼結した。
（６）吸引装置８により約１１０Ｌ／分で吸引した。この時の粉体の不織布における通過速度は１８ｃｍ／秒であった。
（７）トータルで１５分間（片面７分３０秒）粉体を供給した。
【００６９】
この第１構造体における粉体量は１８４ｇ／ｍ²であり、活性炭量は６０ｇ／ｍ²であった。この第１構造体を光学顕微鏡及び電子顕微鏡により観察したところ、粉体が不織布構成繊維の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着していた（図８参照）。
【００７０】
（実施例２）
トータルで３０分間（片面１５分間）粉体を供給したこと、及び粉体の付着した不織布６を温度１２０℃の炉により１０分間熱処理して、粉体同士及び粉体と不織布６とを焼結したこと以外は、実施例１と全く同様にして、第１構造体を製造した。
【００７１】
この第１構造体における粉体量は３１７ｇ／ｍ²であり、活性炭量は１０４ｇ／ｍ²であった。この第１構造体を光学顕微鏡及び電子顕微鏡により観察したところ、粉体が不織布構成繊維の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着していた。
【００７２】
（比較例）
実施例１と同じ活性炭を塩化ビニルエマルジョンバインダーと混合し、分散させた混合溶液を用意した。次いで、この混合溶液中に実施例１と同じ不織布６を浸漬した後、余剰の溶液を搾取して除去し、乾燥して構造体を製造した。この構造体は７０ｇ／ｍ²の活性炭が塩化ビニルバインダー（６０ｇ／ｍ²）により接着されたものであった。この構造体を光学顕微鏡及び電子顕微鏡により観察したところ、繊維の交差点部分に集中して活性炭が接着されていた。
【００７３】
（吸着容量試験）
２５０ｐｐｍのトルエンガスを０．７ｃｍ／秒の流速で、実施例１〜２及び比較例のそれぞれの構造体を通過させ、構造体通過後のトルエン濃度をガスクロマトグラフにより測定し、この濃度が１２．５ｐｐｍ（通過前の濃度の１／２０）となるまでに要する時間（破過時間）を測定した。この破過時間はトルエンガスを非常にゆっくりと通過させているため、吸着容量に相当する。
【００７４】
この破過時間は実施例１が約４５分、実施例２が約１０５分、比較例が約３５分であるため、本発明の構造体は吸着容量に優れていることがわかった。
【００７５】
（吸着性試験）
２５ｐｐｍのトルエンガスを１４ｃｍ／秒の流速で、実施例１〜２及び比較例のそれぞれの構造体を通過させ、構造体通過後のトルエン濃度（ガスクロマトグラフにより測定）と時間との関係を調べた。この結果は表２に示す通りであった。この結果から、本発明の構造体は吸着性に優れていることもわかった。
【００７６】
【表２】

【００７７】
（圧力損失の測定）
実施例１〜２及び比較例の構造体の周速１０ｃｍ／秒における圧力損失を測定した。その結果、実施例１は３Ｐａ、実施例２は４Ｐａ、比較例は３Ｐａであり、本発明の構造体は圧力損失が低いことがわかった。
【００７８】
以上の本発明の構造体の吸着容量試験、吸着性試験、及び圧力損失の結果は、活性炭が不織布構成繊維全体に付着して活性炭同士が密着しておらず、しかも適度な微細孔が形成されており、有効に作用できる活性炭表面が広いためであると考えられた。
【００７９】
（実施例３）
（１）実施例１と同じポリエチレン樹脂粉体のみを、実施例１と同じ供給装置１にセットし、気流発生装置３により空気流（５Ｌ／分）を発生させて粉体を分散装置２へ０．２ｇ／分の量で供給したこと、（２）不織布６に対して片面側のみから粉体を１０分間供給したこと、（３）粉体の付着した多孔性基材６を温度１０４℃の炉により１時間熱処理して焼結したこと以外は、実施例１と全く同様にして、第１構造体を製造した。
【００８０】
この第１構造体における粉体量は５ｇ／ｍ²であった。また、この第１構造体を光学顕微鏡及び電子顕微鏡により観察したところ、粉体が多孔性基材６構成材の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着していた。
【００８１】
（実施例４）
多孔性基材６として、実施例１と同じ不織布６をスパッタリングにより金で繊維表面を被覆したものを使用したこと以外は、実施例３と全く同様にして第１構造体を製造した。
【００８２】
この第１構造体における粉体量は３０ｇ／ｍ²であった。また、この第１構造体を光学顕微鏡及び電子顕微鏡により観察したところ、粉体が不織布構成繊維の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着していた（図９参照）。
【００８３】
（実施例５）
厚さ４０μｍのステンレス板からなり、セルの断面形状が三角形状（一辺が約３ｍｍ、目開き：１．６ｍｍ）のハニカム（たて５ｃｍ、よこ５ｃｍ、高さ２ｃｍ）を用意した。次いで、このハニカムの片面（セルの長さ方向と直交する面）にアクリル樹脂を塗装（厚さ：０．５ｍｍ）し、これを多孔性基材６として使用した。そして、粉体の供給を片面側のみから１５分間実施したこと以外は、実施例１と全く同様にして、第１構造体を製造した。
【００８４】
この第１構造体における粉体量は約２ｇであった。また、この第１構造体を光学顕微鏡及び電子顕微鏡により観察したところ、粉体が多孔性基材６構成材の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着していた（図１０参照）。
【００８５】
（実施例６）
（１）粉体として酸化銅（平均粒径：５．３μｍ（体積分布）、不定形）を使用したこと、（２）粉体の分散装置２への供給量を１．５ｇ／分としたこと、（３）多孔性基材６の片側のみから粉体を１０分間供給した後に、窒素雰囲気下、温度１，０１５℃の炉により３０分間熱処理したこと、以外は実施例５と全く同様にして、第１構造体を製造した。
【００８６】
この第１構造体における粉体量は約５ｇであった。また、この第１構造体を光学顕微鏡及び電子顕微鏡により観察したところ、粉体が多孔性基材６構成材の表面全体に、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着していた（図１１参照）。
【００８７】
【発明の効果】
本発明の構造体は、所定形状を有する多孔性基材と粉体とを含み、この粉体がこの多孔性基材構成材の表面全体に、外観上、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着したものであるか、外観上、粉体が粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で凝集していることにより、所定形状が形成されており、しかも粉体の凝集によって、多孔性基材を除去したことによる中空状態が形成されたものである。このように本発明の構造体は粉体同士が密着した状態にないため、粉体の機能を十分に発揮することができ、しかも処理流体が構造体を通過する場合には通過抵抗の低いものである。
【００８８】
本発明の構造体の製造方法は、（１）粉体を単極性に帯電させる工程、（２）帯電した粉体を気流の作用及び電界の作用により所定形状を有する多孔性基材へ供給し、前記気流を多孔性基材を通過させて、多孔性基材構成材の表面全体に、外観上、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着させる工程、とを含む方法、又は（１）粉体を単極性に帯電させる工程、（２）帯電した粉体を気流の作用により、接地された多孔性支持体上に載置された所定形状を有する多孔性基材へ供給し、前記気流を多孔性基材を通過させて、多孔性基材構成材の表面全体に、外観上、粉体の密充填時に形成される微細孔よりも大きな微細孔を有する状態で付着させる工程、とを含む方法であり、上述のような構造体を容易に製造できる方法である。
【００８９】
本発明の構造体の製造装置は、（１）粉体の供給手段、（２）粉体を単極性に帯電させる手段、（３）帯電した粉体に対して気流を作用させて多孔性基材へ供給し、前記気流を多孔性基材を通過させることができる手段、（４）帯電した粉体に対して電界を作用させて多孔性基材へ供給できる手段、とを含む装置、或いは（１）粉体の供給手段、（２）粉体を単極性に帯電させる手段、（３）帯電した粉体に対して気流を作用させて多孔性基材へ供給し、前記気流を多孔性基材を通過させることができる手段、（４）多孔性基材を支持できる接地された多孔性の支持手段、とを含む装置であり、上述のような構造体を容易に製造できる装置である。
【図面の簡単な説明】
【図１】 本発明の構造体の模式的外観図
【図２】 本発明の別の構造体の模式的外観図
【図３】 本発明の構造体製造装置の模式的断面図
【図４】 本発明の別の構造体製造装置の模式的断面図
【図５】 本発明の更に別の構造体製造装置の模式的断面図
【図６】 本発明の更に別の構造体製造装置の模式的断面図
【図７】 本発明の更に別の構造体製造装置の模式的断面図
【図８】 実施例１の構造体の電子顕微鏡写真
【図９】 実施例４の構造体の電子顕微鏡写真
【図１０】 実施例５の構造体の電子顕微鏡写真
【図１１】 実施例６の構造体の電子顕微鏡写真
【符号の説明】
１ 供給装置
２ 分散装置
３ 気流発生装置
４ 帯電空間
５ 帯電装置
５’ 電界発生装置
５ａ’ 気流上流側の電極
５ｂ’ 気流下流側の電極
６ 多孔性基材
７ 支持体
８ 吸引装置
９ 微細孔[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure, more specifically, a structure in which powder adheres to a porous substrate, a structure in which powder is aggregated, a method for manufacturing the structure, and a device for manufacturing the structure.
[0002]
[Prior art]
For example, a deodorizing filter in which a functional powder such as activated carbon is supported on a porous substrate such as a nonwoven fabric or a woven fabric is known. This deodorizing filter is fixed to a porous substrate by, for example, impregnating and adhering a dispersion solvent in which a functional powder and binder particles are dispersed in a solvent, and then drying by heat. Can be manufactured. However, a part or all of the surface of the functional powder of the deodorizing filter manufactured by such a method is covered with a binder, and when dried, the powder is agglomerated and closely packed, and the powder adheres closely. Since it was easy to be in a state, the original function of the functional powder could not be fully exhibited. In particular, when the passing speed of the processing fluid (liquid or gas) passing through the deodorizing filter is high, the above phenomenon is remarkable.
[0003]
In particular, when a dispersion solvent in which a functional powder and binder particles are dispersed in a solvent is attached to a porous substrate made of fibers such as non-woven fabric, it adheres to the intersection between fibers, Since the powders are likely to be in close contact with each other, it has been difficult to exhibit sufficient functions of the functional powder. Therefore, attempts have been made to fix more functional powders to the porous substrate so that sufficient functions of the functional powders can be exhibited. Since more binder is required, the rigidity of the deodorizing filter is increased, the processability is poor, the resistance when the processing fluid passes is high, and it cannot be used.
[0004]
On the other hand, a technique for attaching fine particles to a porous substrate by electrostatic force is also known, but what can be formed by such a technique has a film layer on the surface of the porous substrate. Therefore, even if the functional powder is attached to the porous substrate in place of the fine particles, the functional powder adheres in the form of an intimate film, so that the function of the functional powder is sufficiently exhibited. It was difficult to manufacture what can Further, since a film layer is formed on the surface of the porous substrate, there is a problem that the resistance when the processing fluid passes is high.
[0005]
[Problems to be solved by the invention]
The present invention has been made to solve the above-described problems, and is a structure that can sufficiently exhibit the function of powder, and a structure that has low passage resistance when a processing fluid passes through the structure, and An object of the present invention is to provide a method for manufacturing the structure, and a manufacturing apparatus for the structure.
[0006]
[Means for Solving the Problems]
The structure of the present invention includes a porous base material having a predetermined shape and a powder, and this powder is formed on the entire surface of the porous base material constituting material when the powder is closely packed. It is attached in a state having fine pores larger than the fine pores, or by appearance, the powder is agglomerated in a state having fine pores larger than the fine pores formed when the powder is densely packed. A predetermined shape is formed, and the powder is agglomerated , By removing the porous substrate A hollow state is formed. As described above, since the structure of the present invention is not in a state where the powders are in close contact with each other, the function of the powder can be sufficiently exerted, and when the processing fluid passes through the structure, the passage resistance is low. It is.
[0007]
The structure manufacturing method of the present invention includes (1) a step of charging a powder to a single polarity, and (2) supplying the charged powder to a porous substrate having a predetermined shape by the action of an air current and the action of an electric field. , Passing the air stream through a porous substrate; Or a step of adhering to the entire surface of the porous base material in a state having fine pores larger than the fine pores formed when the powder is closely packed, or (1) a powder. Step of charging to a single polarity, (2) The charged powder was grounded by the action of airflow Porous Supply to a porous substrate having a predetermined shape placed on a support, Passing the air stream through a porous substrate; Adhering to the entire surface of the porous base material in a state having fine pores larger than the fine pores that are formed when the powder is densely packed, and having the structure as described above It is a method which can manufacture a body easily.
[0008]
The structure manufacturing apparatus of the present invention includes (1) powder supply means, (2) means for charging the powder unipolarly, and (3) an air stream acting on the charged powder to form a porous substrate. Supply to material And allowing the air flow to pass through the porous substrate A device capable of supplying the porous powder by applying an electric field to the charged powder, or (1) a powder supply device, and (2) a unipolar powder. (3) Supplying air to air on the charged powder and supplying it to the porous substrate And allowing the air flow to pass through the porous substrate Means, (4) grounded capable of supporting the porous substrate Porous A device including a supporting means, which can easily manufacture the structure as described above.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
One structure of the present invention (hereinafter sometimes referred to as “first structure”) includes a porous base material having a predetermined shape and a powder, and the powder is a surface of the porous base material. The entire surface is adhered in a state having fine pores larger than the fine pores formed when the powder is closely packed. Examples of the shape of the porous substrate that can be used in the present invention include, for example, the shape of a sheet (for example, a nonwoven fabric, a woven fabric, a knitted fabric, and a composite thereof), a shape obtained by folding a sheet into a zigzag shape, a honeycomb shape, and a sheet. There are a shape in which the sheet is rounded into a cylindrical shape, a shape in which the sheet is folded into a zigzag shape and rounded into a cylindrical shape, and a shape in which the sheet is processed into a bag shape.
[0010]
For example, when the porous substrate has a honeycomb shape, it is preferable to use a cell having a cell opening of about 0.1 to 10 mm, although it varies depending on the powder. Note that the cell opening means the shortest side length when the cross-sectional shape in the direction perpendicular to the cell length direction is a square, and the area equal to the cross-sectional area when it is not a square. The diameter of a circle having a is considered an opening.
[0011]
In the case where the porous substrate is made of a fiber sheet, a nonwoven fabric in which the fibers are not in close contact with each other, the fiber surface area of the entire porous substrate is large, and more powder can be supported is preferable. In the case of this suitable non-woven fabric, the fiber diameter of the fibers constituting the non-woven fabric can be about 0.1 to 1,000 μm, but it is preferably at least 1 times the average particle size of the powder, and 2 times The above is more preferable. When the cross-sectional shape of the fiber is non-circular, the diameter of a circle having the same area as the cross-sectional area of the fiber is regarded as the fiber diameter.
[0012]
Although the thickness of a nonwoven fabric is not specifically limited, About 0.1-100 mm is suitable. Further, the average pore diameter of the nonwoven fabric is preferably 5 times or more of the average particle diameter of the powder, and preferably 10 times or more so that the powder can easily enter the inside of the nonwoven fabric. The average pore size of this nonwoven fabric can be measured with a pore size distribution measuring device (for example, Coulter Porometer, manufactured by Coulter Inc.), and the average particle size of the powder can be measured by a laser diffraction / scattering method or the like.
[0013]
The porous substrate of the present invention can be used with any electrical characteristics. That is, conductivity (specific resistance: 10 ⁰ Less than Ω · cm), semiconductive (specific resistance: 10) ⁰ -10 ⁹ Ω · cm), insulation (specific resistance: 10 ⁹ Any of (over Ω · cm) can be used. However, as described later, it is necessary to pay attention to the combination with the powder.
[0014]
On the other hand, as the powder constituting the first structure of the present invention, for example, a functional powder, an adhesive powder capable of bonding powders, and the like can be used alone or in combination. More specifically, functional powders include porous substances (for example, activated carbon, zeolite, etc.), ceramics having a catalytic function (for example, titanium oxide, copper oxide, manganese dioxide, zinc oxide, etc.), magnetic substances (For example, iron oxide), those having specific electrical characteristics (for example, piezoelectricity, pyroelectricity, etc.), polymers having an ion exchange function, water-absorbing polymers, and the like can be used.
[0015]
Examples of the adhesive powder include organic polymers (for example, polyamide resin powder, polyester resin powder, polyethylene resin powder, polypropylene resin powder, polystyrene resin powder, etc.), organic solids (for example, paraffin). Etc.), glass, solids that are liquid at room temperature (for example, ice) and the like. The adhesive powder is composed of two or more components, the component having an adhesive action at the time of bonding constitutes part or all of the surface, and the component that does not exhibit the adhesive action at the time of bonding constitutes the inside of the powder. Since the shape of the adhesive powder can be maintained at the time of bonding, it can be attached to the porous substrate in a state having larger micropores, or the entire surface of the functional powder is more difficult to cover. There is an effect. For example, the adhesive powder in which the component that exhibits the fusion action at the time of heat fusion constitutes part or all of the surface and the component that does not soften at the time of heat fusion constitutes the inside of the powder has the above-described effects. Play.
[0016]
Although the average particle diameter of these powders is not particularly limited, so that the powder can be stably supplied in terms of penetration into the porous substrate, adhesion to the porous substrate, and production. The thickness is preferably about 0.01 to 50 μm, and more preferably about 0.1 to 30 μm. In addition, it is preferable to use adhesive powder together so that the powders and the powder and the porous substrate can be firmly fixed. When this adhesive powder is used in combination, the powder other than the adhesive powder can be firmly bonded by being interposed between the powder and between the powder and the porous substrate. It is preferable to use an adhesive powder having an average particle size smaller than that of the body (for example, functional powder). The powder may have any shape, for example, a spherical shape, a fiber shape, or a whisker shape.
[0017]
These powders are semiconductive (specific resistance: 10 ⁰ -10 ⁹ Ω · cm) to insulation (specific resistance: 10 ⁹ (> Ω · cm) can be used, but attention must be paid to the combination with the porous substrate. Here, combinations of the porous substrate and the powder are shown in Table 1.
[0018]
[Table 1]

[0019]
Among these combinations, (1) when the powder is composed only of powder other than the adhesive powder, the porous substrate is insulative or semiconductive, and the powder is semiconductive, (2) When powders other than adhesive powder and adhesive powder are included as powder, regardless of the type of porous substrate, either powder of adhesive powder or powder other than adhesive powder Is preferably a semiconductive combination. By adopting such a combination, moderate conductivity can be obtained, and the attached powder does not accumulate electric charge too much, so that the amount of attached powder can be increased.
[0020]
The first structure of the present invention includes the porous base material and powder as described above, and this powder is in a state of adhering to the entire surface of the porous base material constituting material. This "entire surface of the porous substrate constituting material" means the entire surface of the material constituting the porous substrate. For example, when the porous substrate is made of fibers such as a nonwoven fabric Means the entire surface of all the fibers (that is, the surface of the fibers inside the nonwoven fabric when the nonwoven fabric has a thickness).
[0021]
In addition, the powder adheres in a state having fine pores larger than the fine pores formed when the powder is closely packed. Thus, since the powder is not in an intimate contact state and is easy to contact with the processing fluid or the like, the function of the powder can be sufficiently exhibited. Further, when the processing fluid passes through the first structure, the passage resistance is low. The fine pores formed when the powder is closely packed are fine pores formed when the powder is two-dimensionally arranged so that the powders are in close contact with each other. Is a fine hole formed between two adjacent powders when the powders are arranged in a staggered manner. Since the powder does not have a fixed shape and a fixed size, the “micropores formed during close packing” can be measured as follows. First, the powder is dispersed in a suitable solvent, and this dispersion is cast on a substrate such as a glass plate. As the solvent, an organic solvent such as alcohol is used when the powder is hydrophobic, and water or the like is used when the powder is hydrophilic. Regardless of whether the powder is hydrophobic or hydrophilic, water containing an appropriate surfactant can be used. That is, a solvent having excellent affinity with the powder is used. Next, the powder on the substrate is dried and solidified. Then, a micrograph of the dried and solidified powder is taken, and the micropores are measured from this micrograph. Note that the size of the micropores in the present invention (for example, micropores formed when the powder is densely packed or micropores formed by adhesion of the powder of the first structure) is the area of the micropores. The diameter of a circle having the same area.
[0022]
“Appearance” means a state in which the first structure is observed two-dimensionally from the outside (for example, with a microscope), and the first structure may be observed from any direction. For example, in the case of the first structure in which the powder adheres to the nonwoven fabric, it may be observed from the same direction as the thickness direction of the first structure, or observed from a direction perpendicular to the thickness direction of the first structure. You may do it. The first structure is observed from at least two directions, and when observed from either direction, the first structure is attached in a state having fine pores larger than the fine pores formed when the powder is densely packed. preferable. For example, when the first structure is made of a non-woven fabric with powder attached thereto, when observed from the same direction as the thickness direction of the first structure, and from a direction perpendicular to the thickness direction of the first structure In both cases of observation, it is preferable that the powder adheres to the porous substrate with fine pores larger than the fine pores formed when the powder is closely packed. In such a state, the adhesion between the powders is lower, the contact with the processing fluid is easy, and the function of the powder can be further exhibited.
[0023]
The fine holes 9 formed by the powder of the first structural body of the present invention may be dispersed with substantially the same size (see FIG. 1), or the fine holes 9 having various sizes. (See FIG. 2) may be mixed.
[0024]
Another structure of the present invention (hereinafter sometimes referred to as a “second structure”) is a state in which the powder has fine pores larger than the fine pores formed when the powder is closely packed. A predetermined shape is formed by agglomeration, and a hollow state is formed by agglomeration of the powder. Similarly to the first structure, the second structure is in a state where the powder has fine pores larger than the fine pores formed when the powder is closely packed, and the powders are in close contact with each other. Since it is not in the state, the function of the powder can be sufficiently exhibited, and when the processing fluid passes through the second structure, the passage resistance is low. In particular, the second structure has a hollow state formed by agglomeration of the powder, and since the surface area on which the powder can act is wider, the function of the powder can be further exerted, and the processing fluid is the second. When passing through the structure, the passage resistance is much lower.
[0025]
The difference between the second structure and the first structure is that (1) the powder is agglomerated to form a predetermined shape, and (2) the powder is agglomerated to form a hollow state. Only the points that are formed are different. That is, the only difference is that the porous substrate is not included. Other than this difference, it is exactly the same as the first structure described above, and only these differences will be described.
[0026]
First, (1) the shape formed by agglomeration of the powder is not particularly limited. For example, the shape of a sheet (for example, a nonwoven fabric, a woven fabric, a knitted fabric, a composite of these, etc.) , The shape of the sheet folded into a zigzag shape, the honeycomb shape, the shape of the sheet rolled into a cylindrical shape, the shape of the sheet folded into a zigzag shape into a cylindrical shape, the shape of the sheet processed into a bag shape and so on.
[0027]
Next, (2) that the hollow state is formed by the agglomeration of the powder means that when the second structure is cut from any direction, a contour is formed by the powder, and the powder is placed inside the contour. The state that does not exist.
[0028]
In this way, the first and second structures of the present invention can sufficiently exhibit the function of powder, and when the processing fluid passes through the first or second structure, the passage resistance is low. Therefore, gas filters (for example, deodorizing filters, filters for removing specific gaseous substances, decomposition filters such as exhaust gas and ozone, catalyst-carrying filters such as photocatalysts), liquid filters (for example, water purification filters, pure water production) Filter), or a microorganism carrier.
[0029]
The 1st structure of this invention can be manufactured as follows, for example.
[0030]
After charging the powder to a single polarity, an air current and an electric field are applied to the charged powder to supply it to a porous substrate having a predetermined shape, and the entire surface of the porous substrate constituent material has an appearance. In addition, the first structure of the present invention can be manufactured by adhering in a state of having fine pores larger than the fine pores formed when the powder is closely packed. In this way, the airflow acts on the powder and is supplied to the porous substrate, forcibly reaching the entire porous substrate, that is, the inside and the back surface of the porous substrate. Adhere to the entire surface. In addition, since the powder is unipolarly charged and the electric field is also acting, it is easy to adhere to the entire surface of the porous base material due to electrostatic attraction acting between the porous base material. Since the repulsive force acts between the powder, the powder is partially unevenly distributed (for example, at the intersection of fibers) with fine pores larger than the fine pores formed when the powder is closely packed. It adheres to the whole surface of a porous substrate constituent material, without doing. When the first structure is manufactured by such a method, it is easy to monitor the adhesion amount of the powder by utilizing the airflow resistance or the first structure having a desired airflow resistance. There is also an effect that can be easily manufactured.
[0031]
As a method for charging the powder to a single polarity, for example, DC corona discharge, creeping corona discharge (AC corona discharge), X-ray charging, friction charging, or the like can be used. Among these, when X-ray charging is used, (1) the powder is difficult to adhere to the X-ray generator, (2) the electric field strength in the charging space 4 can be increased, and (3) harmful gases such as ozone are generated. There are advantages such as difficult to do.
[0032]
The polarity is not particularly limited, and may be positive or negative, or the positive and negative polarities may be made to act alternately. In addition, this charging is preferably performed by supplying the powder in a gas (preferably in the air) and dispersing it in individual powders so that the entire powder can be charged.
[0033]
Next, an air stream is applied to the charged powder and supplied to the porous substrate. The airflow may be any airflow, but it is preferable to use air that is easy to handle without danger of ignition. Moreover, since the passing speed of the airflow through the porous substrate varies depending on the kind of the porous substrate, the size of the porous substrate, the charged state of the porous substrate, etc., it cannot be limited. It is preferably about seconds. In addition, the passage speed of the gas in the porous base material may be constant, or may be changed regularly or irregularly, but by changing the passage speed, the portion of the porous base material (for example, Depending on the thickness direction when the porous substrate is made of a nonwoven fabric, it is also possible to change the amount of powder adhered. Furthermore, it is preferable to suck the gas from the side opposite to the powder supply side to the porous substrate so that the powder adheres to the entire surface of the porous substrate constituting material.
[0034]
Further, the supply of the powder to the porous base material does not have to be performed once, and can be performed from the same direction or from different directions more than once. For example, when a porous base material consists of a nonwoven fabric, if a powder is supplied from both surfaces of a nonwoven fabric, the 1st structure which adhered uniformly to the whole surface of a nonwoven fabric constituent fiber can be manufactured. When powder is supplied from both sides of the nonwoven fabric in this way, the powder and powder are supplied so that the powder once supplied and adhered does not fall off by the second supply of powder. It is preferable to supply the powder for the second time after bonding the body and the fiber. The powder supplied for the first time and the powder supplied for the second time or later may be the same or different.
[0035]
In the present invention, since an electric field is applied in addition to the above-described action of the air flow, the powder adheres to the entire surface of the porous substrate constituent material by electrostatic attraction acting between the porous substrate and the surface. Can be made. The electric field strength applied to the charged powder cannot be limited because it varies depending on the type of the porous substrate, the size of the porous substrate, the charged state of the porous substrate, etc. It is preferably about 000 V / cm.
[0036]
The direction in which the charged powder is supplied to the porous substrate is preferably from the direction in which the airflow easily passes. For example, when the porous substrate is made of a nonwoven fabric, it is the same as the thickness direction of the nonwoven fabric. It is preferable to supply from the direction, and when the porous substrate has a honeycomb shape, it is preferable to supply from the same direction as the length direction of the cells of the honeycomb.
[0037]
Furthermore, when the porous substrate has a honeycomb structure made of a conductive material, electric field concentration occurs, and charged powder tends to be deposited near the surface on the powder supply direction side. In this case, an insulator having substantially the same opening (shape and size) as the opening of the honeycomb is disposed above the powder supply direction side of the porous substrate having the honeycomb structure, and the above-described tendency is achieved. Can be prevented. Note that a thickness of about 0.1 to 2 mm is sufficient for the insulator.
[0038]
Another manufacturing method of the first structure according to the present invention (hereinafter, also referred to as “second manufacturing method”) is that the powder is charged to a single polarity, and then the charged powder is grounded by the action of airflow. Is supplied to a porous base material having a predetermined shape placed on the support, and the whole surface of the porous base material is larger in appearance than the fine pores formed when the powder is densely packed. It is the method of making it adhere in the state which has a micropore. This second manufacturing method and the above-described manufacturing method (hereinafter sometimes referred to as “first manufacturing method”) are porous on the grounded support instead of applying an electric field to the charged powder. The only difference is that the substrate is placed. When the porous substrate is placed on the grounded support as in the second manufacturing method, a potential difference is generated between the support and the support due to the electric charge of the powder supplied by the airflow. As in the case of the manufacturing method, since it has a state having an electric field, in principle, it is the same as the first manufacturing method.
[0039]
The support that can be used in the second production method is conductive (specific resistance: 10) so that a potential difference is generated between the charged powder and the support. ⁰ Less than Ω · cm) to semiconductive (specific resistance: 10 ⁰ -10 ⁹ A material made of a material of Ω · cm) can be used. Further, it is preferable to use a porous material such as a net or a perforated plate so as not to disturb the flow of the airflow.
[0040]
The first structure of the present invention can be manufactured, for example, by the method as described above, but the first structure manufactured by the method as described above has the powder electrostatically attached to the surface of the porous substrate. It is preferable to fix the adhered powder because it may fall off due to vibration or friction. As this fixing method, for example, when an adhesive powder is included as a powder, there is an adhesion process for adhering the adhesive powder. When the adhesive powder can be bonded by heat, it is preferable to perform the heat treatment at a temperature that can maintain the shape of the adhesive powder, but the adhesive powder is completely melted. Heat treatment can be performed at a temperature to produce a first structure to which the powder adheres in a state having smaller micropores (but larger than micropores formed when the powder is closely packed).
[0041]
The second structure of the present invention can be produced, for example, by fixing the powder of the first structure to which the powder is adhered as described above and removing the porous substrate. Examples of means for fixing and removing the powder include a sintering method and a method of extracting only the porous substrate with a solvent after fixing the powder by the above-described method.
[0042]
When sintered, the powders are bonded and fixed, while the porous substrate is volatilized from the fine holes formed by the powder, and the porous substrate can be removed. Therefore, in the 2nd structure manufactured by sintering, the residue of a porous base material may be included besides powder. In order to produce the second structure by such a method, it is necessary that the powder can be sintered and the porous substrate can be volatilized (for example, composed of an organic component).
[0043]
On the other hand, after the powder is fixed by the above-described method, the second structure manufactured by the method of extracting only the porous substrate with a solvent or the like is substantially composed of only the powder. In order to produce the second structure by such a method, it is necessary to use a powder that is not extracted by the solvent used when extracting the porous substrate.
[0044]
The production apparatus of the present invention can supply (1) a powder supply means, (2) a means for charging the powder to a unipolar polarity, and (3) an air current acting on the charged powder to supply it to the porous substrate. Means (4) means for applying an electric field to the charged powder and supplying it to the porous substrate. Therefore, the first structure can be easily obtained by carrying out the first manufacturing method described above. Can be manufactured.
[0045]
The manufacturing apparatus of this invention is demonstrated based on FIG. 3 which is typical sectional drawing of a manufacturing apparatus. The powder supply device 1 is a device capable of supplying powder to the charging space 4 and functions to adjust the amount of powder supplied to the charging space 4. The amount of powder supplied by the supply device 1 is appropriately set according to the electric field strength of the charging space 4, the amount of powder attached, the type of the porous substrate 6, and the like. In addition, this supply device 1 may be installed in any position, and two or more units may be installed. When two or more supply devices 1 are installed, powders having different blending can be alternately supplied.
[0046]
The dispersing device 2 is installed so as to separate and disperse the powder supplied from the supplying device 1 into individual powders, and to efficiently carry out the charging process of the powder in the charging space 4 as a subsequent process. ing. When two or more kinds of powders are mixed (for example, when a functional powder and an adhesive powder are included), the powder also has an action of mixing these powders.
[0047]
The airflow generation device 3 is connected to the supply device 1 and / or the dispersion device 2 (connected to the dispersion device 2 in FIG. 3), and mainly serves to supply an airflow for supplying the powder to the charging space 4 and is an auxiliary. It serves to supply powder to the porous substrate 6.
[0048]
The charging device 5 acts to charge the powder supplied to the charging space 4 to a single polarity. As the charging device 5, for example, a DC corona discharge device, a creeping corona discharge device (AC corona discharge device) (FIG. 3), an X-ray generator, a friction charging device, or the like can be used. The polarity is not particularly limited, and may be positive or negative, or may be alternately charged to both polarities. In FIG. 3, a single charging device 5 applies a voltage to the support 7 to form an electric field. The strength of the electric field is not particularly limited, but is preferably about 100 to 5,000 V / cm.
[0049]
The charging space 4 is preferably formed in the container so as to suppress powder scattering and to allow the powder to adhere efficiently. The container may be a sealed container or an open container, but when the flow rate of the airflow is controlled by a suction device 8 described later, the container is preferably an open container. The open part may be in any part of the container, but it is located near the charging unit 4 to the charging space 4 and to the charging device 5 side of the charging unit 4 to the charging space 4 of the powder. preferable.
[0050]
The powder charged by the charging device 5 as described above is formed from fine pores formed when the powder is densely packed on the entire surface of the constituent material of the sheet-like porous base material 6 disposed on the downstream side of the airflow. Also adhere in a state having large micropores. This is because the powder is supplied to the entire porous substrate constituent material by the air flow generated by the suction device 8 described later, and the electric field formed by the above-described charging device 5 and the porous substrate. This is because the electrostatic attractive force acts between the powders, and not only is it easily adhered to the entire surface of the porous base material constituting material, but also a repulsive force acts between the powders. In particular, when the porous substrate is made of a low resistance (semiconductive or conductive) material, the powder can be efficiently attached by the action of the ion flow.
[0051]
It is preferable that the arrangement of the sheet-like porous substrate 6 can be changed so that the powder can be supplied to the sheet-like porous substrate 6 from an arbitrary direction. Moreover, it is preferable that the sheet-like porous substrate 6 is supported by a porous support 7 so that airflow can pass therethrough. In FIG. 3, since an electric field is generated between the support 7 and the charging device 5, the conductive support 7 is used.
[0052]
The suction device 8 generates an air flow by suction, (1) an action of supplying the charged powder to the porous substrate 6, and (2) an action of allowing the powder to enter the inside of the sheet-like porous substrate 6. (3) The sheet-like porous substrate 6 has an action of recovering powder that has not adhered to the surface of the constituent material. The passing speed of the airflow through the porous substrate 6 varies depending on the kind of the porous substrate 6, the size of the porous substrate 6, the charged state of the porous substrate 6, etc., but is about 10 to 200 cm / second. It is preferable to suck so that it can pass. In addition, even if the passage speed of the gas in the porous substrate 6 is constant, it may be changed regularly or irregularly.
[0053]
4 is a schematic cross-sectional view of another manufacturing apparatus of the present invention. The manufacturing apparatus of FIG. 3 is different from (1) a direct current corona discharge device as the charging device 5 and (2) a porous substrate. The only difference is that a material having a honeycomb structure is used as the material 6, but even in such a manufacturing apparatus, the material 6 is formed on the entire surface of the constituent material of the porous substrate 6 at the time of dense packing of the powder. It can be made to adhere in the state which has a micropore larger than the micropore made. In particular, when the porous substrate is made of a low resistance (semiconductive or conductive) material, the powder can be efficiently attached by the action of the ion flow.
[0054]
Thus, any device can be used as the charging device 5 as long as the powder can be unipolarly charged. Further, the porous substrate 6 is not particularly limited, and the powder can be attached. In the case of a porous substrate having a honeycomb structure, it is preferable to supply the powder from the same direction as the cell length direction.
[0055]
Further, when the porous substrate 6 has a honeycomb structure made of a conductive material, electric field concentration occurs, and the charged powder is deposited near the surface of the porous substrate 6 on the powder supply direction side. It tends to be easy to do. In this case, an insulator having an opening (shape and size) substantially the same as the opening of the honeycomb is disposed above the powder supply direction side of the porous substrate 6 having the honeycomb structure, as described above. Can prevent the tendency. Note that a thickness of about 0.1 to 2 mm is sufficient for the insulator.
[0056]
FIG. 5 is a schematic cross-sectional view of still another manufacturing apparatus of the present invention. The manufacturing apparatus of FIG. 3 is (1) the point that the air flow generation device 3 is connected to the supply device 1, and (2) the air flow generation device. 3 is a direction in which the powder is supplied to the charging space 4 opposite to the porous substrate 6, and (3) a charging device 5 that generates an electric field for charging the powder, and a charged powder. The electric field generating device 5 ′ for generating an electric field for attaching the body to the porous substrate 6 and generating the electric field separately, but even in this manufacturing apparatus, It can be made to adhere in the state which has a micropore larger than the micropore formed at the time of close packing of powder to the whole surface of the constituent material of porous substrate 6.
[0057]
As described above, the airflow generation device 3 may be connected to the supply device 1, may be connected to the dispersion device 2, or may be connected to both. The powder may be supplied to the charging space 4 from any direction. Further, the electric field for charging the powder and the electric field for attaching the charged powder to the porous substrate 6 may be the same electric field, or may be independent electric fields.
[0058]
Note that the electric field generator 5 ′ for generating an electric field for attaching the charged powder to the porous substrate 6 in the manufacturing apparatus in FIG. 5 can apply a strong electric field to the porous substrate 6. In addition, it is preferable that the distance between the upstream electrode 5′a and the downstream electrode 5′b (support 7) is shorter. However, when the electrode 5′a on the upstream side of the airflow and the porous substrate 6 are brought into contact with each other, it becomes difficult for the powder to adhere to the contacted region, so it is preferable not to make contact. Further, it is preferable that the polarity of the electrode 5′a on the upstream side of the air current is the same as that of the powder so that the powder does not easily adhere to the electrode 5′a on the upstream side of the air current. In the case of the manufacturing apparatus of FIG. 5, the polarity of the electrode 5 ′ a on the upstream side of the airflow is positive. Therefore, it is preferable to charge the powder positively by the charging device 5.
[0059]
FIG. 6 is a schematic cross-sectional view of still another manufacturing apparatus of the present invention. The manufacturing apparatus of FIG. 3 is (1) an X-ray generator is used as the charging device 5, and (2) X-ray generation. There is provided an electric field generator 5 ′ for extracting only unipolar ions from the ions generated from the apparatus, charging the powder, and generating an electric field for attaching the charged powder to the porous substrate 6. Although this point is different, even in this manufacturing apparatus, the entire surface of the constituent material of the porous substrate 6 is adhered in a state having fine pores larger than the fine pores formed when the powder is densely packed. Can do. In particular, when the porous substrate is made of a low resistance (semiconductive) material, the powder can be efficiently attached by the action of the ion flow.
[0060]
The X-ray generator in FIG. 6 is (1) it is difficult for powder to adhere to the X-ray generator, (2) the electric field strength of the charging space 4 can be increased, and (3) it is difficult to generate harmful gases such as ozone. There are advantages, such as.
[0061]
The X-ray generator may be disposed anywhere, but is preferably installed near the region to which the powder is supplied so that the powder can be charged efficiently (in FIG. 6, the ceiling portion of the container). Installed on the outside). Furthermore, when the X-ray generator is installed on the upstream side (with respect to the porous base material) of the electrode 5′a on the upstream side of the airflow as in the embodiment in FIG. 6, the electrode 5 ′ on the upstream side of the airflow As a, it is preferable to use a porous material such as a net or a perforated plate or a thin material when it is non-porous.
[0062]
Another manufacturing apparatus of the present invention (hereinafter sometimes referred to as “second manufacturing apparatus”) includes (1) powder supply means, (2) means for charging the powder to a single polarity, and (3) charged powder. And (4) a grounded support means capable of supporting the porous substrate, and the second manufacturing method described above is carried out. Thus, the first structure can be easily manufactured. This second manufacturing apparatus is different from the above-described manufacturing apparatus (hereinafter sometimes referred to as “first manufacturing apparatus”) only in that it has a grounded support means instead of having a means for directly generating an electric field. (See FIG. 7). In this second manufacturing apparatus, a potential difference is generated between the support and the support body set by the charge of the powder supplied by the air flow, and the electric field is applied as in the case of the first manufacturing apparatus described above. Therefore, in the same manner as in the first manufacturing apparatus described above, the powder is placed in a state where the entire surface of the constituent material of the porous substrate 6 has fine pores larger than the fine pores formed when the powder is closely packed. It can be attached to a porous substrate.
[0063]
The support that can be used in the second production apparatus is conductive (specific resistance: 10) so that a potential difference is generated between the charged powder and the support. ⁰ Less than Ω · cm) to semiconductive (specific resistance: 10 ⁰ -10 ⁹ A material made of a material of Ω · cm) can be used. Further, it is preferable to use a porous material such as a net or a perforated plate so as not to disturb the flow of the airflow.
[0064]
The first structure of the present invention can be manufactured by, for example, the manufacturing apparatus as described above. However, the first structure manufactured by the manufacturing apparatus as described above has the powder electrostatically attached to the surface of the porous substrate. The first manufacturing apparatus and the second manufacturing apparatus are preferably provided with means for fixing the adhered powder because they may fall off due to vibration or friction. This fixing means is preferably a means that can be carried out under no pressure so as not to block the micropores. For example, an apparatus that can be heat-treated with no wind or hot air can be used.
[0065]
Moreover, it is preferable that the 1st and 2nd manufacturing apparatus of this invention is equipped with the means which can fix a powder and can remove a porous base material so that a 2nd structure can be manufactured. Examples of this means include a known sintering furnace and a bath holding a solvent capable of extracting a porous substrate.
[0066]
Examples of the present invention will be described below, but the present invention is not limited to the following examples.
[0067]
【Example】
Example 1
The porous substrate 6 is made of polyester fiber having a fiber diameter of 55.4 μm and has an area density of 70 g / m. ² A nonwoven fabric having a thickness of 5 mm, an average pore diameter of 0.5 mm, and a 100 mm square was prepared. In addition, as the powder, 150-mesh pass (average particle diameter: about 25 μm (volume distribution), manufactured by Kuraray, Kuraray Coal PK-W5) and amorphous activated carbon, and spherical polyethylene resin powder (adhesive with an average particle diameter of 3 μm) Powder).
[0068]
Next, the first structure is the same as that of FIG. 3 except that the airflow generation device is connected to the supply device 1 and that the opening of the container is provided only around the nozzle extending from the dispersion device 2. Manufactured. This condition is as follows.
(1) Activated carbon and polyethylene resin powder are set in a supply device 1 (manufactured by Sankyo Piotech Co., Ltd., Microfeeder MFHV-IVO) at a volume ratio of 3: 2, and then air is supplied from the airflow generator 3 (air compressor). The flow (5 L / min) is supplied to the supply device 1, and the powder is supplied to the dispersion device 2 (manufactured by Sankyo Piotech Co., Ltd., Microfeeder MFHV-IVO) (0.53 g / min). Were dispersed and mixed to form individual powders.
(2) The powder dispersed and mixed by the dispersing device 2 was supplied from the nozzle (diameter 3 mm) to the charging space 4 at a speed of 11.8 m / sec. The supply rate was constant. Moreover, the powder was supplied from a direction perpendicular to a DC electric field (described later). Furthermore, the activated carbon was pulverized by a dispersing device until the average particle size became about 10 μm, and then supplied to the charging space 4.
(3) The charging space 4 was formed in a container (length 14 cm, width 14 cm, height 15 cm). This container used what had an opening part around the nozzle which supplies powder from the dispersion apparatus 2. FIG.
(4) Only positive ions were generated in the charging space 4 by the charging device 5. The charging device 5 used was an alumina plate (thickness: 2 mm) on which one side of a wire (discharge electrode) with a diameter of 50 μm was attached at an interval of 1 cm and a stainless plate (induction electrode) was attached on the opposite side. In addition, creeping discharge was generated by impressing an alternating current with a frequency of 40 KHz and a power of 50 Watts on each electrode. In addition, a potential difference was provided between the charging device 5 and the stainless steel mesh support 7 (opening 1 mm, wire diameter 0.5 mm) to generate a DC electric field (electric field strength 5 KV / 15 cm).
(5) The porous substrate 6 (nonwoven fabric) was placed on the support 7 such that the thickness direction coincided with the direction of the DC electric field. The powder is attached once from one side of the nonwoven fabric, heat treated in a furnace at a temperature of 104 ° C. for 1 hour to sinter the powder and the powder and the nonwoven fabric, and then the nonwoven fabric is turned over so that the first powder The powder was deposited again from the side opposite to the body supply surface. Then, the powder was sintered under the same conditions.
(6) The suction device 8 sucked at about 110 L / min. The passing speed of the powder through the nonwoven fabric at this time was 18 cm / second.
(7) Powder was supplied for a total of 15 minutes (7 minutes 30 seconds on one side).
[0069]
The amount of powder in the first structure is 184 g / m. ² The amount of activated carbon is 60 g / m ² Met. When this first structure was observed with an optical microscope and an electron microscope, the powder adhered to the entire surface of the nonwoven fabric constituting fiber with fine pores larger than the fine pores formed when the powder was closely packed. (See FIG. 8).
[0070]
(Example 2)
The powder was supplied for a total of 30 minutes (15 minutes on one side), and the nonwoven fabric 6 to which the powder adhered was heat-treated in a furnace at a temperature of 120 ° C. for 10 minutes to sinter the powder and the powder with the nonwoven fabric 6 A first structure was manufactured in exactly the same manner as in Example 1 except that.
[0071]
The amount of powder in the first structure is 317 g / m. ² The amount of activated carbon is 104g / m ² Met. When this first structure was observed with an optical microscope and an electron microscope, the powder adhered to the entire surface of the nonwoven fabric constituting fiber with fine pores larger than the fine pores formed when the powder was closely packed. It was.
[0072]
(Comparative example)
The same activated carbon as in Example 1 was mixed with a vinyl chloride emulsion binder to prepare a mixed solution dispersed therein. Subsequently, after the same nonwoven fabric 6 as Example 1 was immersed in this mixed solution, the excess solution was squeezed out and dried, and the structure was manufactured. This structure is 70 g / m ² Activated carbon is vinyl chloride binder (60g / m ² ). When this structure was observed with an optical microscope and an electron microscope, the activated carbon was adhered to the fiber at the intersection.
[0073]
(Adsorption capacity test)
250 ppm of toluene gas was passed through the structures of Examples 1 and 2 and the comparative example at a flow rate of 0.7 cm / second, and the toluene concentration after passing through the structures was measured by a gas chromatograph. The time (breakthrough time) required to reach 5 ppm (1/20 of the concentration before passage) was measured. This breakthrough time corresponds to the adsorption capacity because toluene gas is passed very slowly.
[0074]
Since the breakthrough time was about 45 minutes in Example 1, about 105 minutes in Example 2, and about 35 minutes in Comparative Example, it was found that the structure of the present invention was excellent in adsorption capacity.
[0075]
(Adsorption test)
25 ppm of toluene gas was passed through the structures of Examples 1 and 2 and Comparative Example at a flow rate of 14 cm / second, and the relationship between the toluene concentration (measured by gas chromatograph) after passing the structure and time was examined. . The results are shown in Table 2. From this result, it was also found that the structure of the present invention is excellent in adsorptivity.
[0076]
[Table 2]

[0077]
(Measurement of pressure loss)
The pressure loss at the peripheral speed of 10 cm / sec of the structures of Examples 1 and 2 and the comparative example was measured. As a result, Example 1 was 3 Pa, Example 2 was 4 Pa, and Comparative Example was 3 Pa. The structure of the present invention was found to have a low pressure loss.
[0078]
As a result of the adsorption capacity test, the adsorptivity test, and the pressure loss of the structure of the present invention described above, the activated carbon adheres to the entire nonwoven fabric constituting fibers and the activated carbon does not adhere to each other, and appropriate fine pores are formed. It is thought that this is because the activated carbon surface that can act effectively is wide.
[0079]
Example 3
(1) Only the same polyethylene resin powder as in Example 1 is set in the same supply device 1 as in Example 1, and an air flow (5 L / min) is generated by the air flow generation device 3 to transfer the powder to the dispersion device 2. It was supplied at an amount of 0.2 g / min, (2) the powder was supplied from only one side to the nonwoven fabric 6 for 10 minutes, and (3) the porous substrate 6 to which the powder adhered was at a temperature of 104 ° C. A first structure was manufactured in exactly the same manner as in Example 1 except that it was heat-treated for 1 hour in the furnace and sintered.
[0080]
The amount of powder in the first structure is 5 g / m. ² Met. In addition, when the first structure was observed with an optical microscope and an electron microscope, the powder had fine holes larger than the fine holes formed on the entire surface of the porous base material 6 when the powder was closely packed. It was attached in the state of having.
[0081]
Example 4
A first structure was produced in exactly the same manner as in Example 3, except that the same nonwoven fabric 6 as in Example 1 was used to coat the fiber surface with gold by sputtering as the porous substrate 6.
[0082]
The amount of powder in the first structure is 30 g / m. ² Met. Further, when this first structure was observed with an optical microscope and an electron microscope, the powder adhered to the entire surface of the nonwoven fabric constituting fiber with fine pores larger than the fine pores formed when the powder was closely packed. (See FIG. 9).
[0083]
(Example 5)
A honeycomb (length: 5 cm, width: 5 cm, height: 2 cm) made of a stainless steel plate having a thickness of 40 μm and having a triangular cell cross section (approximately 3 mm on one side, opening: 1.6 mm) was prepared. Next, acrylic resin was coated (thickness: 0.5 mm) on one side of the honeycomb (surface perpendicular to the cell length direction), and this was used as the porous substrate 6. Then, the first structure was manufactured in the same manner as in Example 1 except that the powder was supplied from only one side for 15 minutes.
[0084]
The amount of powder in the first structure was about 2 g. In addition, when the first structure was observed with an optical microscope and an electron microscope, the powder had fine holes larger than the fine holes formed on the entire surface of the porous base material 6 when the powder was closely packed. (See FIG. 10).
[0085]
(Example 6)
(1) Copper oxide (average particle size: 5.3 μm (volume distribution), irregular shape) was used as the powder, and (2) the amount of powder supplied to the dispersing device 2 was 1.5 g / min. (3) Except that the powder was supplied from only one side of the porous substrate 6 for 10 minutes and then heat-treated in a furnace at a temperature of 1,015 ° C. for 30 minutes in a nitrogen atmosphere, exactly as in Example 5. Thus, the first structure was manufactured.
[0086]
The amount of powder in the first structure was about 5 g. In addition, when the first structure was observed with an optical microscope and an electron microscope, the powder had fine holes larger than the fine holes formed on the entire surface of the porous base material 6 when the powder was closely packed. (See FIG. 11).
[0087]
【The invention's effect】
The structure of the present invention includes a porous base material having a predetermined shape and a powder, and this powder is formed on the entire surface of the porous base material constituting material when the powder is closely packed. It is attached in a state having fine pores larger than the fine pores, or by appearance, the powder is agglomerated in a state having fine pores larger than the fine pores formed when the powder is densely packed. A predetermined shape is formed, and the powder is agglomerated , By removing the porous substrate A hollow state is formed. As described above, since the structure of the present invention is not in a state where the powders are in close contact with each other, the function of the powder can be sufficiently exerted, and when the processing fluid passes through the structure, the passage resistance is low. It is.
[0088]
The structure manufacturing method of the present invention includes (1) a step of charging a powder to a single polarity, and (2) supplying the charged powder to a porous substrate having a predetermined shape by the action of an air current and the action of an electric field. , Passing the air stream through a porous substrate; Or a step of adhering to the entire surface of the porous base material in a state having fine pores larger than the fine pores formed when the powder is closely packed, or (1) a powder. Step of charging to a single polarity, (2) The charged powder was grounded by the action of airflow Porous Supply to a porous substrate having a predetermined shape placed on a support, Passing the air stream through a porous substrate; Adhering to the entire surface of the porous base material in a state having fine pores larger than the fine pores that are formed when the powder is densely packed, and having the structure as described above It is a method which can manufacture a body easily.
[0089]
The structure manufacturing apparatus of the present invention includes (1) powder supply means, (2) means for charging the powder unipolarly, and (3) an air stream acting on the charged powder to form a porous substrate. Supply to material And allowing the air flow to pass through the porous substrate A device capable of supplying the porous powder by applying an electric field to the charged powder, or (1) a powder supply device, and (2) a unipolar powder. (3) Supplying air to air on the charged powder and supplying it to the porous substrate And allowing the air flow to pass through the porous substrate Means, (4) grounded capable of supporting the porous substrate Porous A device including a supporting means, which can easily manufacture the structure as described above.
[Brief description of the drawings]
FIG. 1 is a schematic external view of a structure of the present invention.
FIG. 2 is a schematic external view of another structure of the present invention.
FIG. 3 is a schematic cross-sectional view of the structure manufacturing apparatus of the present invention.
FIG. 4 is a schematic cross-sectional view of another structure manufacturing apparatus of the present invention.
FIG. 5 is a schematic cross-sectional view of still another structure manufacturing apparatus of the present invention.
FIG. 6 is a schematic cross-sectional view of still another structure manufacturing apparatus of the present invention.
FIG. 7 is a schematic cross-sectional view of still another structure manufacturing apparatus of the present invention.
8 is an electron micrograph of the structure of Example 1. FIG.
9 is an electron micrograph of the structure of Example 4. FIG.
10 is an electron micrograph of the structure of Example 5. FIG.
11 is an electron micrograph of the structure of Example 6. FIG.
[Explanation of symbols]
1 Supply device
2 Dispersing device
3 Airflow generator
4 Charging space
5 Charging device
5 'Electric field generator
5a 'Upstream electrode
5b 'Electrode on the downstream side of the airflow
6 Porous substrate
7 Support
8 Suction device
9 Micropore

Claims (14)

  A porous substrate including a porous substrate having a predetermined shape and a powder, and the powder has fine pores larger than the fine pores formed on the entire surface of the porous substrate constituting material when the powder is densely packed. A structure characterized by being attached in a state of having. In appearance, the powder is agglomerated in a state having fine pores larger than the fine pores formed when the powder is closely packed, and a predetermined shape is formed . A structure in which a hollow state is formed by removing the substrate . The structure according to claim 1 or 2, wherein the porous substrate is made of a nonwoven fabric, and the average pore diameter of the nonwoven fabric is 5 times or more the average particle size of the powder. The adhesive powder and a powder other than the adhesive powder are included, and the average particle size of the adhesive powder is smaller than the average particle size of the powder other than the adhesive powder. The structure according to any one of claims 3 to 4. (1) Step of charging the powder unipolarly, (2) Supplying the charged powder to the porous substrate having a predetermined shape by the action of airflow and electric field, and passing the airflow through the porous substrate And a step of adhering to the entire surface of the porous base material in a state having fine pores larger than the fine pores formed at the time of dense packing of the powder. Body manufacturing method. (1) a step of charging the powder to a single polarity, and (2) supplying the charged powder to a porous substrate having a predetermined shape mounted on a grounded porous support by the action of an air flow. The step of passing the air flow through the porous base material and adhering the entire surface of the porous base material in a state having fine pores larger than the fine pores formed when the powder is densely packed. The manufacturing method of the structure characterized by including these. Furthermore, the process of fixing powder is included, The manufacturing method of the structure of Claim 5 or Claim 6 characterized by the above-mentioned. Furthermore, the process of fixing a powder and removing a porous base material is included, The manufacturing method of the structure of Claim 5 or Claim 6 characterized by the above-mentioned. The structure according to any one of claims 5 to 8, wherein the charging step is a step of supplying the powder in a gas and charging in a state of being dispersed in each powder. Manufacturing method. (1) Powder supply means, (2) Means for charging the powder unipolarly, (3) Air flow is applied to the charged powder and supplied to the porous substrate, and the air flow is porous An apparatus for manufacturing a structure, comprising: means capable of allowing a substrate to pass through ; and (4) means capable of applying an electric field to charged powder and supplying the powder to a porous substrate. (1) Powder supply means, (2) Means for charging the powder unipolarly, (3) Air flow is applied to the charged powder and supplied to the porous substrate, and the air flow is porous An apparatus for producing a structure comprising: means capable of passing a substrate ; and (4) grounded porous support means capable of supporting a porous substrate . The structure manufacturing apparatus according to claim 10 or 11, further comprising a dispersing device for separating and dispersing the supplied powder into individual powders. The apparatus for manufacturing a structure according to any one of claims 10 to 12, further comprising means for fixing the powder. The apparatus for manufacturing a structure according to any one of claims 10 to 12, further comprising means for fixing the powder and removing the porous substrate.

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