JP2004114356A

JP2004114356A - Cellulosic powder-containing extruded profile and its manufacturing method

Info

Publication number: JP2004114356A
Application number: JP2002277766A
Authority: JP
Inventors: Masaki Wakabayashi; 若林　雅樹; Akira Ishibashi; 石橋　亮; Mamoru Tanaka; 田中　守
Original assignee: YKK AP Inc
Current assignee: YKK AP Inc
Priority date: 2002-09-24
Filing date: 2002-09-24
Publication date: 2004-04-15
Anticipated expiration: 2022-09-24
Also published as: JP4278943B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cellulosic powder-containing extruded profile which can be easily grain-patterned by a simple surface finishing such as sanding with a design-rich appearance and a method for manufacturing the cellulosic powder-containing extruded profile with high productivity and at a low manufacturing cost. <P>SOLUTION: The cellulosic powder, a resin and, if necessary, another additive are mixed and/or kneaded and thereby, two different kinds of materials with different viscosity during molding are prepared. Then the surface layer part formed of a relatively low viscosity material during molding and the core part formed of a relatively high viscosity material during molding, are coextruded monolithically. Thus with the described method, the surface layer part containing at least the resin and the cellulosic powder and the core part containing at least the resin and the cellulosic powder and/or an inorganic powder are monolithically extrusion-molded into the cellulosic powder-containing extruded profile. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明はセルロース系粉体含有押出形材及びその製造方法に関し、さらに詳しくは、表層部の材料によって中心部の材料の周囲が一体的に被覆されていると共に、意匠性に優れる外観を有し、またサンディング等の簡単な表面処理により木目様の模様を容易に作出することができるセルロース系粉体含有押出形材及びその製造方法に関するものである。
【０００２】
【従来の技術】
従来からこの種のセルロース系粉体含有押出形材の開発は種々行なわれ、特に充填材にセルロース系粉体を用いることは木屑、木質系建築廃材、古紙等の資源の再利用を図るために有効な方法である。また、セルロース系粉体含有押出形材のセルロース系粉体の割合を多くし、ポリオレフィンの割合を少なくすることが経済的に有利であり、さらに木粉が多くなるに従って、優れた木質感が得られる。このような組成のセルロース系粉体含有複合樹脂成形品は、例えば、特許文献１に開示されている。
【０００３】
しかしながら、前記セルロース系粉体含有押出形材に用いられる材料においては、表層部や中心部の区別がなく、中心部にも意匠性に優れる表層部と同様の配合の材料を用いていたため、使用できる材料に制限があった。また、表層部に意匠性を有する材料を用い、中心部に意匠性を必要としない材料を用いても、表層部の成形加工時の材料の粘度が中心部の材料の粘度と同じか或いは高いと、表層部の材料が中心部の材料の周囲を被覆することが困難である。仮に押出成形時の加圧力を高めて無理やり被覆しようとした場合、中心部の形態がいびつになるため、変形したり強度的に均一なものが得られないという問題があった。
【０００４】
【特許文献１】
特公昭５９−３０１７６号公報（特許請求の範囲）
【０００５】
【発明が解決しようとする課題】
本発明は、前記したような問題に鑑みなされたものであり、その目的は、表層部の材料の成形加工性に優れ、容易に中心部の材料の周囲を被覆することができると共に、意匠性に優れる外観を有し、またサンディング等の簡単な表面処理により木目様の模様を容易に作出することができ、消費者のニーズに充分に対応可能なセルロース系粉体含有押出形材、及びこのようなセルロース系粉体含有押出形材を生産性よく低コストで製造できると共に、表層部として装飾性を備えた組成の材料を被覆することで、中心部に原料自体が既に種々の顔料や染料で着色されている廃材や再生樹脂の粉体や、粒径及び／又は種類の異なる粉体を混合して用いることができ、資源の有効利用や地球環境保護に資することができる方法を提供することにある。
【０００６】
【課題を解決するための手段】
前記目的を達成するために、本発明によれば、少なくとも樹脂（Ａ）とセルロース系粉体（Ｂ）とを含む表層部と、少なくとも樹脂（Ａ）とセルロース系粉体及び／又は無機系粉体（Ｂ’）とを含む中心部とが一体的に押出成形されてなるセルロース系粉体含有押出形材であって、上記表層部の成形加工時の材料の粘度が、上記中心部の成形加工時の材料の粘度よりも低いことを特徴とするセルロース系粉体含有押出形材が提供される。
好適な態様においては、表層部は、樹脂（Ａ）とセルロース系粉体（Ｂ）とをＡ：Ｂ＝９０〜１０：１０〜９０の比率（質量比）で含み、その厚みが０．５〜３ｍｍであり、かつ、中心部の組成が表層部とは異なる。中心部は、樹脂（Ａ）とセルロース系粉体及び／又は無機系粉体（Ｂ’）とをＡ：Ｂ’＝９０〜１０：１０〜９０の比率（質量比）で含む。また、別の好適な態様においては、中心部に含まれるセルロース系粉体及び／又は無機系粉体が、表層部に含まれるセルロース系粉体及び／又は無機系粉体とは異なる種類及び／又は粒径からなる。
【０００７】
さらに本発明によれば、前記セルロース系粉体含有押出形材の製造方法も提供され、その基本的な態様は、１３０℃で測定したときの揮発成分が０．５質量％以下となるように調整したセルロース系粉体を、樹脂、好ましくは再生ポリオレフィン等の再生樹脂、及び必要に応じて他の添加剤と共に混合及び／又は混練し、成形加工時の粘度が異なる２種の材料を調製し、相対的に成形加工時の材料の粘度が低い表層部と成形加工時の材料の粘度が高い中心部とを共押出により一体的に押出成形することを特徴としている。
【０００８】
【発明の実施の形態】
本発明者らは、前記した課題を達成すべく鋭意研究した結果、セルロース系粉体含有押出形材の製造において、セルロース系粉体を含む表層部の成形加工時の材料の粘度がセルロース系粉体及び／又は無機系粉体を含む中心部の成形加工時の材料の粘度よりも低い場合、表層部の材料の成形加工性に優れ、容易に中心部の材料の周囲を被覆することができ、意匠性に優れる外観を有すると共にサンディング等の簡単な表面処理により木目様の模様を容易に作出することができ、消費者のニーズに充分に対応可能なセルロース系粉体含有押出形材が得られること、また、表層部として装飾性を備えた組成の材料を被覆することで、中心部に原料自体が既に種々の顔料や染料で着色されている廃材や再生樹脂の粉体や、粒径及び／又は種類の異なる粉体を混合して用いることができ、セルロース系粉体含有押出形材を生産性よく低コストで製造できると共に、資源の有効利用や地球環境保護に資することができることを見出し、本発明を完成するに至ったものである。ここでいう「廃材」とは、セルロース系粉体含有押出形材や木材製品の廃棄物をいい、「再生樹脂」とは、いわゆるリサイクル樹脂のことで、既に一回以上使用された成形加工品等を回収したもの、或いは成形加工工程で発生する不良品や端材等をいう。
【０００９】
本明細書において、「成形加工時の粘度」とは成形加工温度（押出温度）における材料の粘度をいい、例えば「ＪＩＳ　Ｋ　７１９９　熱可塑性プラスチックのキャピラリーレオメータによる流れ特性試験方法」によって測定される。また、その際に用いる装置としては東洋精機製キャピログラフ等が用いられ、その測定条件の一例としては、測定温度（押出温度）１８０℃、剪断速度：６０８ｓｅｃ^−１を採用できるが、２種の材料の粘度を客観的に相対評価できる条件であればよい。また、本発明において、中心部及び表層部の具体的粘度は、中心部の材料の粘度が１０〜５００００Ｐａ・ｓ、好ましくは１００〜１００００Ｐａ・ｓであり、表層部の材料の粘度が５〜４９０００Ｐａ・ｓ、好ましくは５０〜９９００Ｐａ・ｓである。
【００１０】
セルロース系粉体を含む表層部の成形加工時の材料の粘度を、セルロース系粉体及び／又は無機系粉体を含む中心部の成形加工時の材料の粘度よりも低くするための方法としては、如何なる方法であってもよく、例えば、母材樹脂に粘度そのものが低い樹脂を用いる方法、滑剤を加える方法、木粉等のセルロース系粉体の充填量を少なくする方法、充填する木粉等に粒径の小さいものを用いる方法等が挙げられ、これらの手段を単独で又は組み合わせて採用することができる。さらに、中心部に粒径の大きいセルロース系粉体を用い、表層部に粒径の小さいセルロース系粉体を用いた場合、表層部の粘度の低下に加えて、表層部に粒径の大きいセルロース系粉体を用いたセルロース系粉体含有押出形材の場合のように、屋外等で使用した際の雨水等によって表面に露出した木粉の吸水乾燥に伴う膨張収縮によるセルロース系粉体の脱落や、表面の質感の変化、汚れ等の付着を防止し、或いは目立たなくすることができる。
【００１１】
本発明のセルロース系粉体含有押出形材においては、サンディング等の簡単な表面処理によりセルロース系粉体が表面に露出するので、木目様の模様を容易に作出することができるが、表面層の厚みは、０．５〜３ｍｍが好ましい。表面層が０．５ｍｍよりも薄いと、表面樹脂層をサンディング等により除去した場合、中心部が露出し、装飾性が損なわれる恐れがあり、一方、３ｍｍよりも厚いと経済的に不利となる。
【００１２】
以下、本発明のセルロース系粉体含有押出形材の各構成成分について説明すると、中心部は少なくとも樹脂とセルロース系粉体及び／又は無機系粉体を含む材料、表層部は少なくとも樹脂とセルロース系粉体を含む材料よりなる。
【００１３】
前記セルロース系粉体としては如何なるものであってもよく、例えば木粉、竹粉、パルプ、バカス、ケナフ、おが屑、木質繊維、籾殻、破砕チップ材、果実穀粉、古紙等が挙げられ、単独で又は２種類以上を組み合わせて用いることができる。一方、前記無機系粉体としては如何なるものであってもよく、例えば水酸化物、酸化物、無機塩、ケイ酸化合物等が挙げられ、単独で又は２種類以上を組み合わせて用いることができる。
本発明のセルロース系粉体含有押出形材の中心部には、セルロース系粉体及び／又は無機系粉体を単独で又は２種類以上を組み合わせて用いることができ、表層部には前記セルロース系粉体を単独で又は２種類以上を組み合わせて用いることができる。表層部に用いるセルロース系粉体としては、特に木粉を用いることが好ましい。
【００１４】
また、セルロース系粉体及び／又は無機系粉体が水分等の揮発成分を含んでいると、これが加工工程で発泡し、製品不良の原因となる。そのため、セルロース系粉体及び／又は無機系粉体が揮発成分を含んでいる場合、予め乾燥して、１３０℃で測定したときの揮発成分が０．５質量％以下となるように調整することが好ましい。
【００１５】
前記樹脂としては、熱可塑性樹脂であれば如何なるものであってもよいが、特にポリオレフィンが好ましい。ポリオレフィンとしては、如何なるものであってもよく、例えば低密度ポリエチレン、中密度ポリエチレン、高密度ポリエチレン、ポリプロピレン、ポリスチレン、ポリ酢酸ビニル、ポリ塩化ビニル、ポリ塩化ビニリデン、ポリアクリル酸、ポリアクリル酸塩、ポリアクリル酸エステル、ポリブタジエン、ポリイソプレン、ポリクロロプレン、エチレンプロピレンゴム、アクリロニトリル−ブタジエン−スチレン共重合体、アクリロニトリル−エチレンプロピレンゴム−スチレン共重合体、エチレン酢酸ビニル共重合体等が挙げられ、これらを単独で又は２種以上を組み合わせて用いることができる。これらポリオレフィンの中でも、特に、安価で工業的に量産性があること、軽量でかつ剛性に優れ、比較的耐熱性が良好なこと、及び成形性が良いことからポリプロピレンが好適である。
【００１６】
セルロース系粉体含有押出形材における表層部は、樹脂（Ａ）とセルロース系粉体（Ｂ）とをＡ：Ｂ＝９０〜１０：１０〜９０、好ましくは７０〜３０：３０〜７０の比率（質量比）で含むことが適当である。表層部でセルロース系粉体が樹脂との組成比率で１０：９０よりも少なくなると、添加するセルロース系粉体の配合量が少なく天然に近い木質感が極端に損なわれるので好ましくない。一方、セルロース系粉体が樹脂との組成比率で９０：１０よりも多くなると、樹脂がセルロース系粉体及び／又は無機系粉体の各部周囲に回り切らないため、強度に問題のあるセルロース系粉体含有押出形材が得られるので好ましくない。
【００１７】
一方、セルロース系粉体含有押出形材における中心部は、樹脂（Ａ）とセルロース系粉体及び／又は無機系粉体（Ｂ’）とをＡ：Ｂ’＝９０〜１０：１０〜９０、好ましくは７０〜３０：３０〜７０の比率（質量比）で含むことが適当である。中心部でセルロース系粉体及び／又は無機系粉体が樹脂との組成比率で１０：９０よりも少なくなると、比較的に高価な樹脂の配合量が多く経済的に不利になるので好ましくない。一方、セルロース系粉体及び／又は無機系粉体が樹脂との組成比率で９０：１０よりも多くなると、樹脂がセルロース系粉体及び／又は無機系粉体の各部周囲に回り切らないため、強度に問題のあるセルロース系粉体含有押出形材が得られるので好ましくない。
【００１８】
なお、本発明においては、前記各成分の他に、必要に応じて、セルロース系粉体と樹脂、特にポリオレフィンとの親和性を向上させるための不飽和カルボン酸もしくはその誘導体で変性されたポリオレフィン樹脂や、着色剤等の各種添加剤を加えることができる。上記不飽和カルボン酸としては、如何なるものであってもよく、例えば無水マレイン酸、無水イタコン酸、無水シトラコン酸、マレイン酸、イタコン酸、シトラコン酸、クロトン酸、イソクロトン酸、メサコン酸、アンゲリカ酸、ソルビン酸、アクリル酸、メタクリル酸等が挙げられ、これらを単独で又は２種類以上を組み合わせて用いることができる。また、上記不飽和カルボン酸の誘導体としては、如何なるものであってもよく、上記不飽和カルボン酸の金属塩、アミド、イミド、エステル等のうちの１つ或いは２種類以上を組み合わせて用いることができる。
【００１９】
着色剤としては、如何なるものであってもよく、例えば二酸化チタン、酸化コバルト、群青、紺青、弁柄、銀朱、鉛白、鉛丹、黄鉛、ストロンチウムクロメート、チタニウムイエロー、チタンブラック、ジンククロメート、鉄黒、モリブデン赤、モリブデンホワイト、リサージ、リトポン、カーボンブラック、エメラルドグリーン、ギネー緑、カドミウム黄、カドミウム赤、コバルト青、アゾ顔料、フタロシアニンブルー、イソインドリノン、キナクリドン、ジオキサジンバイオレット、ペリノンペリレン等が挙げられ、これらを単独で又は２種類以上を組み合わせて用いることができる。
その他必要に応じて、酸化防止剤、紫外線吸収剤、光安定剤、帯電防止剤、滑剤、難燃剤等の各種添加剤を加えることができる。
【００２０】
本発明のセルロース系粉体含有押出形材の製造に当っては、前記したように１３０℃で測定したときの揮発成分が０．５質量％以下となるように予め乾燥工程等によって調整したセルロース系粉体を、樹脂、好ましくは再生ポリオレフィン等の再生樹脂、及び必要に応じて無機系粉体や他の添加剤と共に混合及び／又は混練し、成形加工時の粘度が異なる２種の材料を調製する。次いで、相対的に成形加工時の材料の粘度が低い表層部と成形加工時の材料の粘度が高い中心部とを、共押出法により一体的に押出成形することよって製造することができる。
【００２１】
前記のような方法により製造されたセルロース系粉体含有押出形材の幾つかの例を図１〜５に示す。図１乃至図３は板状成形品を示しており、図１に示す板状成形板１は中心部２の側周全表面が表層部３で一体的に被覆されており、図２では中心部２の上面のみ、図３では上面と一側面が表層部３で一体的に被覆されている。一方、図４及び図５は中空部４を有する板状成形品１ａを示しており、図４では中心部２の上面のみ、図５では上面と下面が表層部３で一体的に被覆されている。当然のことながら、本発明はこれらの態様に限定されるものではなく、各種形状、構造のセルロース系粉体含有押出形材を製造できる。
【００２２】
また、得られた押出形材は、サンディング等の簡単な表面処理により木目様の模様を容易に作出することができ、さらには、研削、研磨、切断、彫刻等の加工を施すことによって、サッシ、枠材、壁材、床材、ドア、パネル、笠木、腰板、すのこ、濡れ縁、額縁、デッキ材、屋根、しきり板、雨戸、雨どい、柱、柱カバー、つき板、室内建具用框材及び枠材、花壇、フェンス、ベンチ、門扉、看板、ルーバー、手すり等の製品に仕上げることができる。
【００２３】
【実施例】
以下、実施例及び比較例を示して本発明についてより具体的に説明するが、もちろん本発明は、下記実施例によって何ら限定されるものではない。尚、とくに断りの無い限り、実施例に記載の「部」は「質量部」を示す。下記実施例及び比較例において、押出機としては二軸押出機、単軸押出し機、多軸押出し機或いはその組み合わせのいずれを用いてもよい。さらに、押出機に用いられるスクリュー形状もとくに制限はない。
【００２４】
実施例１
１３０℃で測定したときの揮発成分が０．５質量％以下となるように乾燥した７０ｗｔ％以上が１００メッシュを通過する粒径の木粉１２２部、再生ポリプロピレン１００部、添加剤である無水マレイン酸変性ポリプロピレン１部と顔料１２部を加え、ヘンシェルミキサーで混練し、表層部に用いるコンパウンドを得た。得られたコンパウンドをクラッシャーによって粉砕し、粒径を調整した。また、１３０℃で測定したときの揮発成分が０．５質量％以下となるように乾燥した１００メッシュを３０ｗｔ％以上通過しない粒径が不揃いな木粉１２２部、表層部に用いた材料と同様の再生ポリプロピレン１００部、添加剤である無水マレイン酸変性ポリプロピレン１部からなるコンパウンドを中心部に用いた。中心部に用いたコンパウンドは、表層部に用いたコンパウンドと同様の方法によって作成した。それぞれのコンパウンドを用い、共押出を行なった。以上の方法により、本発明に係るセルロース系粉体含有押出形材を作製した。
【００２５】
実施例２〜５
実施例１において、中心部に用いるコンパウンド中の木粉の粒径を変更した以外は、実施例１と同様の押出条件及び操作を行なうことにより、本発明に係るセルロース系粉体含有押出形材を作製した。
【００２６】
前記実施例１〜５で用いた主要材料及び成形加工時の粘度を表１にまとめて示す。
【表１】

前記実施例１〜５において、セルロース系粉体を含む表層部の成形加工時の材料の粘度が無機系粉体及び／又はセルロース系粉体を含む中心部の成形加工時の材料の粘度よりも低いため、表層部の材料の成形加工性に優れ、容易に中心部の材料の周囲を被覆することができた。
【００２７】
実施例６
１３０℃で測定したときの揮発成分が０．５質量％以下となるように乾燥した７０ｗｔ％以上が１００メッシュを通過する粒径の木粉１２２部、再生ポリプロピレン１００部、添加剤である無水マレイン酸変性ポリプロピレン１部と顔料１２部を加え、ヘンシェルミキサーで混練し、表層部に用いるコンパウンドを得た。得られたコンパウンドをクラッシャーによって粉砕し、粒径を調整した。また、１３０℃で測定したときの揮発成分が０．５質量％以下となるように乾燥した７０ｗｔ％以上が１００メッシュを通過する粒径の木粉１２２部、表層部に用いた樹脂よりも粘度が高い再生ポリプロピレン１００部、添加剤である無水マレイン酸変性ポリプロピレン１部からなるコンパウンドを中心部に用いた。中心部に用いたコンパウンドは、表層部に用いたコンパウンドと同様の方法によって作成した。それぞれのコンパウンドを用い、共押出を行なった。以上の方法により、中心部の周囲を表層部が一体的に被覆するように押出成形された本発明に係るセルロース系粉体含有押出形材を作製した。
【００２８】
実施例７
１３０℃で測定したときの揮発成分が０．５質量％以下となるように乾燥した７０ｗｔ％以上が１００メッシュを通過する粒径の木粉１２２部、再生ポリプロピレン１００部、添加剤である無水マレイン酸変性ポリプロピレン１部と顔料１２部を加え、ヘンシェルミキサーで混練し、表層部に用いるコンパウンドを得た。得られたコンパウンドをクラッシャーによって粉砕し、粒径を調整した。また、１３０℃で測定したときの揮発成分が０．５質量％以下となるように乾燥した１００メッシュを３０ｗｔ％以上通過しない粒径が不揃いな木粉１２２部、既に着色された表層部よりも粘度の高い再生ポリプロピレン１００部、添加剤である無水マレイン酸変性ポリプロピレン１部からなるコンパウンドを中心部に用いた。中心部に用いたコンパウンドは、表層部に用いたコンパウンドと同様の方法によって作成した。それぞれのコンパウンドを用い、共押出を行なった。以上の方法により、中心部の周囲を表層部が一体的に被覆するように押出成形された本発明に係るセルロース系粉体含有押出形材を作製した。
【００２９】
実施例８
１３０℃で測定したときの揮発成分が０．５質量％以下となるように乾燥した７０ｗｔ％以上が１００メッシュを通過する粒径の木粉１２２部、再生ポリプロピレン１００部、添加剤である無水マレイン酸変性ポリプロピレン１部と顔料１２部、滑剤０．３部を加え、ヘンシェルミキサーで混練し、表層部に用いるコンパウンドを得た。得られたコンパウンドをクラッシャーによって粉砕し、粒径を調整した。また、１３０℃で測定したときの揮発成分が０．５質量％以下となるように乾燥した１００メッシュを３０ｗｔ％以上通過しない粒径が不揃いな木粉１２２部、既に着色された表層部よりも粘度の高い再生ポリプロピレン１００部、添加剤である無水マレイン酸変性ポリプロピレン１部からなるコンパウンドを中心部に用いた。中心部に用いたコンパウンドは、表層部に用いたコンパウンドと同様の方法によって作成した。それぞれのコンパウンドを用い、共押出を行なった。以上の方法により、中心部の周囲を表層部が一体的に被覆するように押出成形された本発明に係るセルロース系粉体含有押出形材を作製した。
【００３０】
実施例９
実施例１において、中心部に用いるコンパウンドを既に押出された建築用押出形材の端材を粉砕したものに変更した以外は、実施例１と同様の操作を行なうことにより、中心部の周囲を表層部が一体的に被覆するように押出成形された本発明に係るセルロース系粉体含有建築用押出形材を作製した。
【００３１】
前記実施例６〜９で用いた主要材料及び成形加工時の粘度を表２にまとめて示す。
【表２】

【００３２】
【発明の効果】
以上のように、本発明によれば、セルロース系粉体を含む表層部の成形加工時の材料の粘度が無機系粉体及び／又はセルロース系粉体を含む中心部の成形加工時の材料の粘度よりも低いため、表層部の材料の成形加工性に優れ、容易に中心部の材料の周囲を被覆することができる。また、表層部として装飾性を備えた組成の材料を被覆することで、中心部に原料自体が既に種々の顔料や染料で着色されているものや粒径及び／又は種類の異なる粉体を混合して用いることができので、意匠性に優れる外観を有するセルロース系粉体含有押出形材を生産性よく低コストで製造することができ、資源の有効利用や地球環境保護に資することができると共に、サンディング等の簡単な表面処理により木目様の模様を容易に付与でき、消費者のニーズに充分に応えることができる。
【図面の簡単な説明】
【図１】セルロース系粉体含有押出形材の一例を示す断面図である。
【図２】セルロース系粉体含有押出形材の他の例を示す断面図である。
【図３】セルロース系粉体含有押出形材のさらに他の例を示す断面図である。
【図４】セルロース系粉体含有押出形材の別の例を示す断面図である。
【図５】セルロース系粉体含有押出形材のさらに別の例を示す断面図である。
【符号の説明】
１　板状成形板
１ａ　中空部を有する板状成形品
２　中心部
３　表層部
４　中空部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cellulosic powder-containing extruded shape and a method for producing the same, and more particularly, has a design in which the periphery of the material at the center is integrally coated with the material of the surface portion and has excellent appearance. Also, the present invention relates to a cellulose-based powder-containing extruded shape capable of easily producing a grain-like pattern by a simple surface treatment such as sanding, and a method for producing the same.
[0002]
[Prior art]
There have been various developments of this type of extruded material containing cellulosic powder, especially the use of cellulosic powder as a filler to recycle resources such as wood chips, wood-based building waste, and waste paper. This is an effective method. In addition, it is economically advantageous to increase the proportion of the cellulose powder in the extruded material containing the cellulose powder and to decrease the proportion of the polyolefin, and as the wood powder increases, an excellent woody texture is obtained. Can be A cellulose resin-containing composite resin molded product having such a composition is disclosed in, for example, Patent Document 1.
[0003]
However, in the material used for the extruded profile containing the cellulose-based powder, there is no distinction between the surface layer portion and the central portion, and the material having the same composition as the surface layer portion having excellent design properties is used for the central portion. There were limitations on the materials that could be made. In addition, using a material having a design property for the surface layer portion, and using a material that does not require a design property for the center portion, the viscosity of the material at the time of molding the surface layer portion is equal to or higher than the viscosity of the material of the center portion. Then, it is difficult for the material of the surface layer to cover the periphery of the material at the center. If the pressure is increased during extrusion molding and the coating is forcibly performed, the shape of the central portion is distorted, and there has been a problem that the material cannot be deformed or uniform in strength.
[0004]
[Patent Document 1]
JP-B-59-30176 (Claims)
[0005]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has as its object to excel in the formability of the material of the surface layer portion, and to easily cover the periphery of the material in the central portion, and to improve the design. Extruded shape material containing cellulose-based powder, which has an excellent appearance, can easily produce a grain-like pattern by simple surface treatment such as sanding, and can sufficiently respond to the needs of consumers; and Such cellulose-based powder-containing extruded profiles can be manufactured with good productivity at low cost, and by coating a material with a decorative composition as the surface layer, the raw material itself is already a variety of pigments and dyes in the center. The present invention provides a method that can be used by mixing powders of waste materials and recycled resins, and powders having different particle diameters and / or types, which are colored with, thereby contributing to effective use of resources and protection of the global environment. It is in.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a surface layer containing at least the resin (A) and the cellulose-based powder (B), and at least the resin (A) and the cellulose-based powder and / or the inorganic-based powder A cellulose-based powder-containing extruded shape obtained by integrally extruding a central portion including the body (B ′), wherein the viscosity of the material at the time of molding the surface layer is such that the viscosity of the central portion is reduced. An extruded section containing a cellulosic powder characterized by having a viscosity lower than that of the material during processing is provided.
In a preferred embodiment, the surface portion contains the resin (A) and the cellulose-based powder (B) at a ratio (mass ratio) of A: B = 90 to 10:10 to 90, and has a thickness of 0.5. ３3 mm, and the composition of the central part is different from that of the surface part. The central portion contains the resin (A) and the cellulose-based powder and / or the inorganic-based powder (B ') in a ratio (mass ratio) of A: B' = 90 to 10:10 to 90. In another preferred embodiment, the cellulose-based powder and / or the inorganic-based powder contained in the central portion is of a different type and / or from the cellulose-based powder and / or the inorganic-based powder contained in the surface layer portion. Or it consists of a particle size.
[0007]
Further, according to the present invention, there is also provided a method for producing the above-mentioned extruded profile containing a cellulose-based powder, the basic aspect of which is such that the volatile component measured at 130 ° C. is 0.5% by mass or less. The adjusted cellulosic powder is mixed and / or kneaded with a resin, preferably a regenerated resin such as regenerated polyolefin, and if necessary, other additives to prepare two types of materials having different viscosities during molding. In addition, the surface layer portion having relatively low viscosity of the material during the forming process and the central portion having the high viscosity of the material during the forming process are integrally extruded by co-extrusion.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
The inventors of the present invention have conducted intensive studies to achieve the above-mentioned object, and as a result, in the production of an extruded profile containing a cellulose-based powder, the viscosity of the material at the time of molding the surface layer containing the cellulose-based powder has been reduced to a level of the cellulose-based powder. When the viscosity of the material including the body and / or the inorganic powder at the time of molding is lower than that of the material at the time of molding, the material of the surface layer is excellent in moldability and can easily cover the periphery of the material at the center. It has an appearance with excellent design properties and can easily produce a grain-like pattern by simple surface treatment such as sanding, resulting in an extruded material containing cellulose-based powder that can sufficiently respond to consumer needs. In addition, by coating a material having a decorative property as a surface layer, the central portion of the raw material itself is already colored with various pigments and dyes, and powder of recycled resin or recycled resin, And / or different types The present invention was completed by finding that it is possible to mix and use powders, to produce extruded material containing cellulose-based powder with good productivity at low cost, and to contribute to effective use of resources and protection of the global environment. That is what led to it. The term "waste material" as used herein refers to the waste of extruded shape materials and wood products containing cellulosic powder, and the term "recycled resin" refers to so-called recycled resin, a molded product that has been used at least once. Etc., or defective products or scraps generated in the molding process.
[0009]
As used herein, the term "viscosity during molding" refers to the viscosity of a material at the molding temperature (extrusion temperature), and is measured, for example, by "JIS K 7199 Flow characteristic test method for thermoplastic plastics with capillary rheometer". As an apparatus used at that time, a Capillograph manufactured by Toyo Seiki is used. As an example of the measurement conditions, a measurement temperature (extrusion temperature) of 180 ° C. and a shear rate of 608 sec ⁻¹ can be adopted. Any condition can be used as long as the viscosity of the pulp can be objectively evaluated. In the present invention, the specific viscosity of the central portion and the surface portion is such that the viscosity of the material of the central portion is 10 to 50000 Pa · s, preferably 100 to 10000 Pa · s, and the viscosity of the material of the surface portion is 5 to 49000 Pa. S, preferably 50 to 9900 Pa · s.
[0010]
As a method for lowering the viscosity of the material at the time of molding the surface portion containing the cellulosic powder at the time of molding the central portion containing the cellulosic powder and / or the inorganic powder, Any method may be used, for example, a method of using a resin having a low viscosity itself as a base resin, a method of adding a lubricant, a method of reducing a filling amount of cellulosic powder such as wood powder, a wood powder to be filled, and the like. Examples of such methods include those using particles having a small particle size, and these means can be employed alone or in combination. Further, when a cellulose-based powder having a large particle diameter is used in the center and a cellulose-based powder having a small particle diameter is used in the surface layer, in addition to the decrease in the viscosity of the surface layer, the cellulose having the large particle diameter is used in the surface layer. Of cellulose-based powder due to expansion and shrinkage due to water-absorbing drying of wood powder exposed to the surface due to rainwater when used outdoors, such as in the case of extruded profiles containing cellulose-based powder using cellulose-based powder In addition, it is possible to prevent a change in surface texture and adhesion of dirt or the like, or to make the surface inconspicuous.
[0011]
In the cellulosic powder-containing extruded shaped material of the present invention, since the cellulosic powder is exposed on the surface by a simple surface treatment such as sanding, a grain-like pattern can be easily created. The thickness is preferably 0.5 to 3 mm. When the surface layer is thinner than 0.5 mm, if the surface resin layer is removed by sanding or the like, the central portion is exposed and decorativeness may be impaired. On the other hand, if the surface layer is thicker than 3 mm, it is economically disadvantageous. .
[0012]
Hereinafter, each component of the cellulose-based powder-containing extruded shape of the present invention will be described. The central part is a material containing at least a resin and a cellulose-based powder and / or an inorganic powder, and the surface layer is at least a resin and a cellulose-based material. It is made of a material containing powder.
[0013]
The cellulosic powder may be any, for example, wood flour, bamboo flour, pulp, bacas, kenaf, sawdust, wood fiber, chaff, crushed chip material, fruit flour, waste paper, etc. Alternatively, two or more types can be used in combination. On the other hand, any of the inorganic powders may be used, and examples thereof include hydroxides, oxides, inorganic salts, silicate compounds and the like, and they can be used alone or in combination of two or more.
Cellulose-based powder and / or inorganic powder can be used alone or in combination of two or more in the center of the extruded profile containing cellulose-based powder of the present invention. Powders can be used alone or in combination of two or more. As the cellulosic powder used for the surface layer, it is particularly preferable to use wood powder.
[0014]
In addition, when the cellulose-based powder and / or the inorganic-based powder contain volatile components such as moisture, they are foamed in the processing step, which causes product defects. Therefore, if the cellulose-based powder and / or the inorganic-based powder contains a volatile component, it should be dried in advance and adjusted so that the volatile component measured at 130 ° C. is 0.5% by mass or less. Is preferred.
[0015]
The resin may be any resin as long as it is a thermoplastic resin, and polyolefin is particularly preferable. The polyolefin may be any, for example, low-density polyethylene, medium-density polyethylene, high-density polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl chloride, polyvinylidene chloride, polyacrylic acid, polyacrylate, Polyacrylate, polybutadiene, polyisoprene, polychloroprene, ethylene propylene rubber, acrylonitrile-butadiene-styrene copolymer, acrylonitrile-ethylene propylene rubber-styrene copolymer, ethylene vinyl acetate copolymer, and the like. They can be used alone or in combination of two or more. Among these polyolefins, polypropylene is particularly preferred because it is inexpensive, has industrial mass productivity, is lightweight and has excellent rigidity, has relatively good heat resistance, and has good moldability.
[0016]
The surface layer part of the extruded profile containing the cellulose powder contains the resin (A) and the cellulose powder (B) in a ratio of A: B = 90 to 10:10 to 90, preferably 70 to 30:30 to 70. (Mass ratio) is appropriate. If the ratio of the cellulose-based powder to the resin in the surface layer portion is less than 10:90, the amount of the added cellulose-based powder is small, and the woody texture close to nature is extremely impaired, which is not preferable. On the other hand, when the composition ratio of the cellulosic powder to the resin is more than 90:10, the resin does not wrap around each part of the cellulosic powder and / or the inorganic powder, and therefore, the cellulosic powder having a problem in strength. It is not preferable because a powder-containing extruded shape can be obtained.
[0017]
On the other hand, the central part in the extruded profile containing the cellulose-based powder contains the resin (A) and the cellulose-based powder and / or the inorganic-based powder (B ′) in A: B ′ = 90 to 10:10 to 90; Preferably, it is appropriate to include the compound in a ratio (mass ratio) of 70 to 30:30 to 70. If the ratio of the cellulose-based powder and / or the inorganic-based powder to the resin in the central portion is less than 10:90, the amount of the relatively expensive resin is large, which is economically disadvantageous. On the other hand, when the composition ratio of the cellulose-based powder and / or the inorganic-based powder with the resin is more than 90:10, the resin does not wrap around each part of the cellulose-based powder and / or the inorganic-based powder. It is not preferable because an extruded material containing cellulose powder having a problem in strength is obtained.
[0018]
In the present invention, in addition to the above components, if necessary, a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof for improving the affinity between the cellulose-based powder and the resin, particularly the polyolefin. Alternatively, various additives such as a coloring agent can be added. The unsaturated carboxylic acid may be any, for example, maleic anhydride, itaconic anhydride, citraconic anhydride, maleic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, mesaconic acid, angelic acid, Sorbic acid, acrylic acid, methacrylic acid and the like can be mentioned, and these can be used alone or in combination of two or more. Further, any derivative of the unsaturated carboxylic acid may be used, and one or a combination of two or more of metal salts, amides, imides, and esters of the unsaturated carboxylic acid may be used. it can.
[0019]
The coloring agent may be any, for example, titanium dioxide, cobalt oxide, ultramarine, navy blue, red stalk, silver vermilion, lead white, lead red, graphite, strontium chromate, titanium yellow, titanium black, zinc chromate, Iron black, molybdenum red, molybdenum white, litharge, lithopone, carbon black, emerald green, guinea green, cadmium yellow, cadmium red, cobalt blue, azo pigment, phthalocyanine blue, isoindolinone, quinacridone, dioxazine violet, perinone perylene And the like, and these can be used alone or in combination of two or more.
In addition, various additives such as an antioxidant, an ultraviolet absorber, a light stabilizer, an antistatic agent, a lubricant, and a flame retardant can be added as needed.
[0020]
In the production of the extruded shaped material containing a cellulose-based powder of the present invention, the cellulose previously adjusted by a drying step or the like such that the volatile component measured at 130 ° C. is 0.5% by mass or less as described above. The system powder is mixed and / or kneaded with a resin, preferably a regenerated resin such as a regenerated polyolefin, and, if necessary, an inorganic powder or other additives, and two kinds of materials having different viscosities during molding processing are mixed. Prepare. Next, the surface layer portion having a relatively low viscosity of the material at the time of molding and the central portion having a relatively high viscosity of the material at the time of molding can be manufactured by integrally extruding by co-extrusion.
[0021]
Some examples of the cellulosic powder-containing extruded profiles produced by the above method are shown in FIGS. FIGS. 1 to 3 show a plate-like molded product. The plate-like molded plate 1 shown in FIG. 1 has a central portion 2 entirely covered with a surface layer 3 on the entire side circumference, and FIG. In FIG. 3, only the upper surface 2 is integrally covered with the surface layer 3 on the upper surface and one side surface. On the other hand, FIGS. 4 and 5 show a plate-shaped molded product 1 a having a hollow portion 4. In FIG. 4, only the upper surface of the center portion 2 is covered, and in FIG. I have. As a matter of course, the present invention is not limited to these embodiments, and can produce cellulose-based powder-containing extruded shapes having various shapes and structures.
[0022]
In addition, the obtained extruded shaped material can easily produce a wood-like pattern by a simple surface treatment such as sanding, and further, can be processed by grinding, polishing, cutting, engraving, etc. , Frame materials, wall materials, floor materials, doors, panels, copings, wainscots, slats, wet edges, picture frames, deck materials, roofs, strips, shutters, gutters, pillars, pillar covers, attached boards, frame materials for indoor fittings And it can be finished into products such as frame materials, flower beds, fences, benches, gates, signs, louvers, handrails and the like.
[0023]
【Example】
Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. However, the present invention is not limited to the following Examples. Unless otherwise specified, “parts” described in the examples indicate “parts by mass”. In the following Examples and Comparative Examples, any of a twin-screw extruder, a single-screw extruder, a multi-screw extruder, or a combination thereof may be used as the extruder. Furthermore, the shape of the screw used in the extruder is not particularly limited.
[0024]
Example 1
122 parts of wood flour having a particle size of 70% by weight or more passing through a 100 mesh dried so that the volatile component becomes 0.5% by mass or less when measured at 130 ° C., 100 parts of recycled polypropylene, and anhydrous maleic as an additive 1 part of acid-modified polypropylene and 12 parts of pigment were added and kneaded with a Henschel mixer to obtain a compound used for the surface layer. The obtained compound was pulverized with a crusher to adjust the particle size. Further, 122 parts of wood powder having an irregular particle size that does not pass through 30% by weight or more of 100 mesh dried so that the volatile component measured at 130 ° C. becomes 0.5% by mass or less, and the same as the material used for the surface layer portion A compound consisting of 100 parts of recycled polypropylene and 1 part of a maleic anhydride-modified polypropylene as an additive was used in the center. The compound used for the central part was prepared by the same method as the compound used for the surface part. Coextrusion was performed using each compound. By the above-mentioned method, the extruded profile containing the cellulose-based powder according to the present invention was produced.
[0025]
Examples 2 to 5
Extruded material containing cellulose-based powder according to the present invention by performing the same extrusion conditions and operation as in Example 1 except that the particle size of the wood flour in the compound used in the central part was changed in Example 1. Was prepared.
[0026]
Table 1 shows the main materials used in Examples 1 to 5 and the viscosities at the time of molding.
[Table 1]

In Examples 1 to 5, the viscosity of the material at the time of molding the surface layer portion containing the cellulose-based powder is lower than the viscosity of the material at the time of molding the central portion containing the inorganic powder and / or the cellulose-based powder. Since the material was low, the processability of the material of the surface layer was excellent, and the periphery of the material at the center could be easily covered.
[0027]
Example 6
122 parts of wood flour having a particle size of 70% by weight or more passing through a 100 mesh dried so that the volatile component becomes 0.5% by mass or less when measured at 130 ° C., 100 parts of recycled polypropylene, and anhydrous maleic as an additive 1 part of acid-modified polypropylene and 12 parts of pigment were added and kneaded with a Henschel mixer to obtain a compound used for the surface layer. The obtained compound was pulverized with a crusher to adjust the particle size. In addition, 122 parts of wood powder having a particle size of 70% by weight or more that passes through a 100 mesh when dried at a volatile component of 0.5% by mass or less when measured at 130 ° C. has a viscosity higher than that of the resin used for the surface layer. The compound consisting of 100 parts of recycled polypropylene having a high content and 1 part of maleic anhydride-modified polypropylene as an additive was used in the center. The compound used for the central part was prepared by the same method as the compound used for the surface part. Coextrusion was performed using each compound. By the above-mentioned method, the extruded profile containing the cellulose-based powder according to the present invention, which was extruded so that the surface portion integrally covered the periphery of the central portion, was produced.
[0028]
Example 7
122 parts of wood flour having a particle size of 70% by weight or more passing through a 100 mesh dried so that the volatile component becomes 0.5% by mass or less when measured at 130 ° C., 100 parts of recycled polypropylene, and anhydrous maleic as an additive 1 part of acid-modified polypropylene and 12 parts of pigment were added and kneaded with a Henschel mixer to obtain a compound used for the surface layer. The obtained compound was pulverized with a crusher to adjust the particle size. Also, 122 parts of wood powder having an irregular particle size that does not pass 30 wt% or more through a 100 mesh dried so that the volatile component measured at 130 ° C. becomes 0.5% by mass or less, and more than the already colored surface layer portion A compound consisting of 100 parts of recycled polypropylene having a high viscosity and 1 part of maleic anhydride-modified polypropylene as an additive was used in the center. The compound used for the central part was prepared by the same method as the compound used for the surface part. Coextrusion was performed using each compound. By the above-mentioned method, the extruded profile containing the cellulose-based powder according to the present invention, which was extruded so that the surface portion integrally covered the periphery of the central portion, was produced.
[0029]
Example 8
122 parts of wood flour having a particle size of 70% by weight or more passing through a 100 mesh dried so that the volatile component becomes 0.5% by mass or less when measured at 130 ° C., 100 parts of recycled polypropylene, and anhydrous maleic as an additive 1 part of acid-modified polypropylene, 12 parts of pigment, and 0.3 part of lubricant were added, and kneaded with a Henschel mixer to obtain a compound used for a surface layer. The obtained compound was pulverized with a crusher to adjust the particle size. Also, 122 parts of wood powder having an irregular particle size that does not pass 30 wt% or more through a 100 mesh dried so that the volatile component measured at 130 ° C. becomes 0.5% by mass or less, and more than the already colored surface layer portion A compound consisting of 100 parts of recycled polypropylene having a high viscosity and 1 part of maleic anhydride-modified polypropylene as an additive was used in the center. The compound used for the central part was prepared by the same method as the compound used for the surface part. Coextrusion was performed using each compound. By the above-mentioned method, the extruded profile containing the cellulose-based powder according to the present invention, which was extruded so that the surface portion integrally covered the periphery of the central portion, was produced.
[0030]
Example 9
In Example 1, the same operation as in Example 1 was performed except that the compound used for the center portion was changed to a crushed piece of extruded architectural extruded material. An extruded profile for cellulosic powder-containing building according to the present invention, which was extruded so that the surface layer portion was integrally coated, was produced.
[0031]
Table 2 summarizes the main materials used in Examples 6 to 9 and the viscosity during molding.
[Table 2]

[0032]
【The invention's effect】
As described above, according to the present invention, the viscosity of the material at the time of molding the surface portion containing the cellulose-based powder is lower than the viscosity of the material at the time of molding the central portion containing the inorganic powder and / or the cellulose-based powder. Since the viscosity is lower than the viscosity, the material of the surface layer has excellent moldability and can easily cover the periphery of the material at the center. In addition, by coating a material having a decorative property as a surface layer, a material in which the raw material itself is already colored with various pigments or dyes or a powder having a different particle size and / or type is mixed at the center. As it can be used, it is possible to produce a cellulose-based powder-containing extruded shape having an appearance with excellent design properties with good productivity at low cost, and to contribute to effective use of resources and protection of the global environment. A simple grain treatment, such as sanding, can easily impart a grain-like pattern, and can sufficiently respond to consumer needs.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of an extruded material containing a cellulose-based powder.
FIG. 2 is a cross-sectional view showing another example of an extruded profile containing a cellulose-based powder.
FIG. 3 is a cross-sectional view showing still another example of an extruded shape material containing a cellulose-based powder.
FIG. 4 is a cross-sectional view showing another example of an extruded profile containing a cellulose-based powder.
FIG. 5 is a cross-sectional view showing still another example of an extruded material containing a cellulose-based powder.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Plate-shaped molded plate 1a Plate-shaped molded product having a hollow part 2 Central part 3 Surface part 4 Hollow part

Claims

A surface layer portion containing at least the resin (A) and the cellulose-based powder (B) and a central portion containing at least the resin (A) and the cellulose-based powder and / or the inorganic powder (B ′) are integrally formed. A cellulosic powder-containing extruded shape formed by extrusion molding, wherein the viscosity of the material at the time of molding the surface layer portion is lower than the viscosity of the material at the time of molding the central portion. Extruded material containing cellulosic powder.

The surface layer portion contains the resin (A) and the cellulose-based powder (B) at a ratio (mass ratio) of A: B = 90 to 10:10 to 90, a thickness of 0.5 to 3 mm, and 2. The extruded profile containing cellulose-based powder according to claim 1, wherein the composition of the central portion is different from that of the surface portion.

The cellulose-based powder and / or the inorganic-based powder contained in the central portion are of a different type and / or particle size from the cellulose-based powder and / or the inorganic-based powder contained in the surface portion. The extruded shaped material containing a cellulosic powder according to claim 1.

The central portion contains the resin (A) and the cellulose-based powder and / or the inorganic-based powder (B ′) in a ratio (mass ratio) of A: B ′ = 90 to 10:10 to 90. The extruded shaped material containing a cellulosic powder according to any one of claims 1 to 3.

The surface layer portion contains the resin (A) and the cellulose-based powder (B) at a ratio of A: B = 70-30: 30-70 (mass ratio). Item 2. The extruded shaped material containing cellulosic powder according to item 1.

The cellulose-based powder according to any one of claims 1 to 5, wherein the inorganic-based powder is at least one selected from the group consisting of a hydroxide, an oxide, an inorganic salt, and a silicate compound. Extrusion profiles containing powder.

The center part contains the resin (A) and the cellulose-based powder (B) in a ratio (mass ratio) of A: B = 70 to 30:30 to 70 (A / B). Item 2. The extruded shaped material containing cellulosic powder according to item 1.

The cellulosic powder is at least one selected from the group consisting of wood flour, bamboo flour, pulp, bacas, sawdust, wood fiber, rice hull, and waste paper. Item 6. The extruded shape material containing a cellulosic powder according to item 6.

The cellulosic powder-containing extruded profile according to any one of claims 1 to 7, wherein the cellulosic powder is wood flour.

The extruded profile containing a cellulosic powder according to any one of claims 1 to 9, wherein the resin is a polyolefin.

The resin-based extruded shape according to any one of claims 1 to 9, wherein the resin is polypropylene.

The cellulose-based powder-containing extruded shape according to any one of claims 1 to 11, wherein the resin is a recycled material.

The surface portion and / or the central portion is selected from the group consisting of a resin further modified with an unsaturated carboxylic acid or a derivative thereof, a colorant, an antioxidant, an ultraviolet absorber, a light stabilizer, an antistatic agent and a lubricant. The extruded profile containing a cellulose-based powder according to any one of claims 1 to 12, further comprising at least one additive.

Cellulose-based powder adjusted to have a volatile component of 0.5% by mass or less when measured at 130 ° C. is mixed and / or kneaded with a resin and other additives as necessary, and used during molding. Two types of materials having different viscosities are prepared, and the surface layer portion where the viscosity of the material is relatively low at the time of molding and the central portion where the viscosity of the material is high at the time of molding are integrally extruded by co-extrusion. A process for producing a cellulosic powder-containing extruded profile characterized by the following.

The method according to claim 14, wherein the resin is a recycled polyolefin.