JP2004168408A

JP2004168408A - Extensible container and its manufacture method

Info

Publication number: JP2004168408A
Application number: JP2002339539A
Authority: JP
Inventors: Koichi Ohara; 弘一大原; Yutaka Urayama; 豊浦山; Masayoshi Mochizuki; 正快望月
Original assignee: Toppan Printing Co Ltd; Daicel Pack Systems Ltd
Current assignee: Daicel Pack Systems Ltd; Toppan Inc
Priority date: 2002-11-22
Filing date: 2002-11-22
Publication date: 2004-06-17

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an extensible container by forming a resin sheet, which is in an elastic state wherein it can be extended to a height double or more when using. <P>SOLUTION: The container is formed by molding a resin sheet while the container comprises a bottom wall 1 and side walls 2, with the side walls having, when in an extended state, a first peripheral wall part 3 inclined inward from an opening part toward the bottom wall 1, a second peripheral wall part 4 inclined inward from the first peripheral wall part 3, through the medium of a first hinge part 7, toward the opening part, a third peripheral wall part 5 extending sideward from the second peripheral wall part through the medium of a second hinge part, and a fourth peripheral wall part 6 extending from the third peripheral wall part toward the bottom wall. At the second peripheral wall part 4, the third peripheral wall part 5 and the fourth peripheral wall part 6, vertical walls 10 to 12 are formed mutually adjacent to one another in the peripheral direction while extending along the same line in the radial direction. The container can be extended to a height double its height or more by an extending operation, while making use of the hinge parts and the vertical walls. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、コンパクトな収縮又は圧縮状態から使用に際して容器の形態に可逆的に伸長できる伸縮性容器及びその製造方法に関する。
【０００２】
【従来の技術】
伸縮性容器として、底壁とこの底壁から延びる蛇腹状の筒体とで構成された容器が知られている。この容器は、伸長状態の筒体を蛇腹状に成形し、流通過程では軸方向に収縮することによりコンパクト化している。しかし、蛇腹状の筒体を収縮させた状態では、屈曲部にストレス又は応力が集中するため、長期間保存すると、屈曲部にピンホールや割れが生じる可能性が大きい。さらに、伸長状態から収縮させて容器をコンパクト化するため、生産性を向上させることが困難である。特に、収縮に対して反発性の高い蛇腹状筒体では、収縮状態を維持するために容器を圧縮状態に維持する必要がある。さらに、適度な強度を保持させるためには、容器の厚みも比較的厚くする必要があり、経済的に不利である。
【０００３】
実公平５−４０８４３号公報には、カップ状の容器本体と、この容器本体のしたに段部を介して連接された挽きコーヒーを収納し、該容器本体よりも小径のコーヒー収納部とを薄肉合成樹脂で成形したコーヒー抽出器であって、前記容器本体の下半分の周面部に縦襞を設け、この縦襞の上縁部に折目線を形成し、段部の外周縁部よりに環状凹溝部を設け、前記縦襞を設けた周面部をその上縁の折目線から容器本体の内側へ折り込んでコーヒー収納部を前記容器本体の上部内周面部内へ収納させたコーヒー抽出器（又は容器）が開示されている。この容器では、コーヒー収納部をコンパクトに収納できるとともに、使用に際してコーヒー収納部を容器本体から下方に押し出してコーヒー抽出器として利用できる。しかし、この容器では、容器本体内に収納部を収納するため、収納部を伸長させた状態に比べて収縮状態での高さを１／２以下とすることが困難である。そのため、容積を低減するのに制限があり、輸送コストや保管コストをさらに低減することが困難である。
【０００４】
特許第３０５１３３１号明細書には、底面部と、上部が大径となる傾斜状に形成された下側円周面部とを有する下側部材と、前記下側円周面部の上端と第１ヒンジ部を介して外側下方に下部が大径となる傾斜状に一体に連接された中間円周部を有する中間部材と、前記中間円周面部下端と第２ヒンジ部を介して外側上方に上部が大径となる傾斜状に一体に連接された上側円周面部を有する上側部材とを備えた伸張式容器が開示されている。この容器では、前記下側円周面部及び中間円周面部に、それぞれ、外面側には露出せず内面側の上下方向に放射状の伸縮溝部が形成されており、前記中間部材を前記第１のヒンジ部及び第２ヒンジ部を介して上方へ反転し伸張することにより、その伸張された中間円周面部が前記下側円周面部及び上側円周面部とほぼ連続する容器側壁面を形成する。
【０００５】
この容器では、前記放射状の伸縮溝部は中間部材の反転を容易にし、収縮動作に伴って、容器内側へ膨らむ曲面に形成された前記中間円周面部が、上方への反転に伴って外側へ膨らむ曲面となるため、腰を強くできる。また、伸縮溝部が下側円周面部及び中間円周面部の内面側に形成されているため、反転操作に伴って外面側には大きな張力が作用する。そのため、収縮した状態の容器を反転動作により伸張させるには、大きな力を必要とし、伸張した容器を円滑に形成できない。特に、非発泡樹脂シートを用いて容器を形成すると、伸張操作に大きな反転力を必要とする。
【０００６】
特表平６−５０８５９０号公報には、同心的なリングからなる三次元的形状の容器において、底部に続いて複数の同心的な環状壁部が配置され、非常に薄い壁肉の環状範囲（ヒンジ部）を介して、隣接し、かつ傾斜角度を有する壁部が互いに結合している容器が開示されている。この容器では、大きく傾斜した環状壁部が隣接する壁部の上に折り返されて容器が折り畳まれる。そのため、コンパクトな容器を形成できる。しかし、環状壁部を折り畳んで容器の容積を小さくすると、ヒンジ部に大きな応力が作用し、ヒンジ部が損傷する可能性がある。特に、容器の深さが大きくなると、折り畳み操作に伴ってヒンジ部に大きな拡張力及び収縮力が作用するため、ヒンジ部を利用しても環状襞部を折り畳むことが困難となる。
【０００７】
【発明が解決しようとする課題】
従って、本発明の目的は、可逆的に伸縮可能であり、かつ伸長操作により所定形状の容器を形成できる伸縮性容器及びその製造方法を提供することにある。
【０００８】
本発明の他の目的は、非発泡樹脂シートで形成しても、伸縮操作により円滑に伸長又は収縮できるとともに、収縮状態よりも２倍以上の高さに伸張できる伸縮性容器及びその製造方法を提供することにある。
【０００９】
本発明のさらに他の目的は、シートからコンパクトな容器に成形できるとともに、使用に際して容積の大きな容器の形態に円滑に伸長できる伸縮性容器、およびこのような伸縮性容器を高い生産性で製造できる方法を提供することにある。
【００１０】
【課題を解決するための手段】
本発明者らは、前記課題を達成するため鋭意検討した結果、樹脂シートからの容器成形において、伸長可能な容器を収縮したコンパクトな形態で成形すると、伸縮性容器の生産性を大きく向上できること、容器成形において、複数のヒンジ部を介して開口部側に向かって段階的に径大となる複数の周壁部を形成するとともに、これらの周壁部の周方向に縦襞を形成すると、円滑に伸張（又は展開）及び収縮可能な容器が得られることを見いだし、本発明を完成した。
【００１１】
すなわち、本発明の伸縮性容器は、底壁と、この底壁から開口部に向かって全体として外方に傾斜した側壁とで構成されている。そして、前記容器では、前記側壁が、屈曲可能な複数のヒンジ部を介して縦方向に複数の周壁部を備えており、複数の周壁部に、縦方向の同一線上に沿って（換言すれば、位置ずれすることなく）延びる縦襞が互いに隣接して形成されており、前記開口部側の周壁部に対して底壁側の周壁部が相対的に折返し可能である。すなわち、伸長操作により、前記底壁側の周壁部は開口部側の周壁部に対して退動して伸長又は展開し、収縮操作に伴って、前記底壁側の周壁部は開口部側の周壁部に対して前進又は侵入して収縮（又は収容）可能である。なお、前記側壁は、開口部に向かって連続的に径大となって傾斜していてもよいが、通常、前記複数の周壁部により段階的に径大となって傾斜している。なお、各周壁部は開口部に向かって漸次径大であってもよい。
【００１２】
前記容器において、側壁は、開口部側の上周壁部と、底壁側の下周壁部と、前記上周壁部と下周壁部との間に介在する複数の中間周壁部とで構成してもよく、少なくとも１つの中間周壁部の両側にはヒンジ部が形成されている。このような側壁を有する容器では、収縮した状態で、複数の中間周壁部と下周壁部とが、開口部に向かって断面山形の多角形状（例えば、断面ブリッジ状又は断面山形の多角ブリッジ状）に形成され、伸長した状態で、前記中間周壁部及び上周壁部が底壁から開口部側に向かって段階的に径大となって傾斜していてもよい。より詳細には、側壁は、開口部から底壁に向かって内方へ傾斜する第１の周壁部と、第１のヒンジ部を介して前記第１の周壁部から開口部に向かって内方へ傾斜する第２の周壁部と、第２のヒンジ部を介して前記第２の周壁部から横方向に延びる第３の周壁部と、この第３の周壁部から底壁へ延びる第４の周壁部とを備えていてもよい。
【００１３】
このような容器において、収縮した状態において、底壁面に対する垂直角を基準角としたとき、少なくとも１つの中間周壁部は開口部に向かって基準角からの角度１０〜６０°で内方へ傾斜し、前記下周壁部側の中間周壁部は横方向（又は基準角から角度６０〜１２０°で内方へ傾斜して）へ延びていてもよい。例えば、収縮した状態で、第１の周壁部が開口部から底壁に向かって内方に傾斜し、第２の周壁部が第１のヒンジ部から開口部に向かって内方に傾斜しており、第３の周壁部が第２のヒンジ部から実質的に横方向に延びていてもよい。より詳細には、収縮した状態において、底壁面に対する垂直角を基準角としたとき、第１の周壁部が開口部に向かって基準角からの角度５〜３０°で外方へ傾斜し、第２の周壁部が開口部に向かって基準角からの角度１０〜５０°で内方へ傾斜し、第３の周壁部が基準角からの角度７０〜１１０°で横方向に延びていてもよい。
【００１４】
また、少なくとも第２の周壁部及び第３の周壁部に縦襞を互いに隣接して形成し、第１のヒンジ部を所定幅（細幅）に形成してもよい。また、第２の周壁部と第３の周壁部との間の境界域（第２のヒンジ部）は、線状（例えば、折曲線状）に形成してもよく、環状リブ（凸状又は凹状環状リブ）として形成してもよい。なお、第１のヒンジ部は、平滑部として形成してもよい。前記縦襞は、半径方向又は放射方向に延びる同一線上に沿って形成すればよく、縦襞は、補強性を高めるためヒンジ部（例えば、前記第１のヒンジ部などの開口部側のヒンジ部）で途切れてもよく、縦襞は、屈曲性を高めるため、ヒンジ部（例えば、前記第２のヒンジ部などの底壁側のヒンジ部）で連続して形成してもよい。前記縦襞は、通常、周方向への伸縮により、周方向の応力を吸収可能である。このような縦襞は放射状に形成してもよい。例えば、周方向に隣接する縦襞の幅は、開口部方向に向かって幅広（例えば、漸次幅広）に形成してもよい。
【００１５】
なお、補強性を高めるため、開口部側の上周壁部は、開口部に向かって径大となる複数の環状段部を備えており、かつ開口周縁部に折返し部を有していてもよい。本発明の伸縮性容器は、非発泡樹脂シートで形成しても、伸長及び収縮操作を円滑に行うことができる。
【００１６】
本発明の方法では、樹脂シート（非発泡又は発泡樹脂シート）を成形し、前記構造の伸縮性容器を製造する。この方法では、例えば、樹脂シートの成形により、底壁と、この底壁から開口部に向かって全体として外方に傾斜した周壁部を備えた側壁とで構成され、かつ前記開口部側の周壁部に対して底壁側の周壁部が相対的に収縮状態から伸長可能な容器を製造する。このような方法において、シートの成形加工により、屈曲可能な複数のヒンジ部を介して半径方向に複数の周壁域と、前記複数の周壁域に、半径方向の同一線上に沿って延び、かつ周方向に互いに隣接する縦襞とを形成して収縮状態の容器を成形し、伸縮性容器を製造できる。
【００１７】
【発明の実施の形態】
以下に、必要に応じて添付図面を参照しつつ本発明を詳細に説明する。
【００１８】
図１は本発明の伸縮性容器の一例を示す概略斜視図であり、図２は図１の伸縮性容器を示す部分端面図である。図３は図１の伸縮性容器の伸長状態を示す概略斜視図であり、図４は図３の伸縮性容器を示す部分端面図である。
【００１９】
伸縮性容器は、図１及び図２に示すように、非発泡樹脂シートの容器成形により収縮又は圧縮状態で形成されている。この容器は、周縁部に環状凹部１ａが形成された円形状の底壁１と、この底壁から縦方向に延びる同心円状の側壁２とで構成されている。この側壁２は、複数の周壁部３〜６で構成され、開口部に向かって全体として段階的に径大となって外方に傾斜している。すなわち、図３及び図４に示すように、前記側壁２は、開口部から底壁に向かって内方へ傾斜する第１の周壁部３と、この第１の周壁部から開口部に向かって内方へ傾斜する第２の周壁部４と、この第２の周壁部から横方向に延びる第３の周壁部５と、この第３の周壁部５から底壁１へ延びる第４の周壁部６とを備えており、第１の周壁部３、第２の周壁部４及び第３の周壁部５の角度は、底壁１側にいくにつれて漸次小さく形成されている。なお、開口部側の第１の周壁部３は、補強性を高めるため、開口部に向かって径大となる複数の環状段部３ａ，３ｂ，３ｃを備えているとともに、開口周縁部には折返し部３ｄを有している。
【００２０】
前記側壁２には、屈曲可能な複数のヒンジ部が形成されている。この例では、前記第２の周壁部４の両側にヒンジ部が形成されている。すなわち、前記第１の周壁部３と第２の周壁部４との間には第１のヒンジ部７が介在し、第２の周壁部４と第３の周壁部５との間には第２のヒンジ部８が介在する。また、第３の周壁部５と第４の周壁部６との間の境界域も屈曲可能な第３のヒンジ部９として機能する。前記第１のヒンジ部７は、容器を伸長させた状態で第１の周壁部３を環状の形態に保持するため、平滑な細幅（例えば、０．１〜０．５ｍｍ程度の幅）に形成され、第２のヒンジ部８は、収縮操作により第３の周壁部５を内方（又は開口部側）へ円滑に折り込み又は反転させるため、線状（又は折り曲げ線状）に形成されている。
【００２１】
さらに、周方向に伸縮性を付与し、伸長（又は展開）及び収縮操作に伴う周方向の応力を吸収するため、複数の周壁部の周方向には、縦襞が互いに隣接して形成されている。すなわち、第１の周壁部３を除く周壁部（第２の周壁部４、第３の周壁部５及び第４の周壁部６）には、それぞれ、縦方向又は半径方向の同一線上に沿って位置ずれすることなく、縦方向又は半径方向に延びる多数の縦襞１０，１１，１２が周方向に隣接して形成されている。さらに、伸長状態又は展開状態で、補強性を付与し、形状を円形状に保持するため、第１のヒンジ部７では縦襞１０が途切れている。一方、屈曲性や収縮性（又は折り込み性）を高めるため、第２のヒンジ部８では縦襞１０，１１が連続して形成されている。なお、周方向に隣接する縦襞１０〜１２の幅は、放射状、すなわち開口部方向に向かって漸次幅広に形成されている。また、縦襞はほぼ均等な厚みの凹凸状周壁部を形成しており、周壁部の内外面において、周方向の伸縮襞として機能する。
【００２２】
このような収縮又は成形状態の容器は、図１及び図２に示すように、第１の周壁部３内に、第２の周壁部４、第３の周壁部５及び第４の周壁部６が収容されたコンパクトな形態を有しており、第２乃至第４の周壁部４〜６は、開口部に向かって断面山形の台形状（又はブリッジ状、多角ブリッジ状）に形成されている。すなわち、第２の周壁部４は第１のヒンジ部７から開口部側にいくにつれて内方に傾斜しており、第３の周壁部５は、収縮又は成形状態の容器において第２のヒンジ部８を介して前記第２の周壁部４から実質的に横方向に延びている。より具体的には、図２に示すように、収縮又は成形した状態において、底壁１面に対する垂直角を基準角としたとき、開口部に向かって、第１の周壁部３は基準角からの角度５〜１５°で第１のヒンジ部７から容器の外方へ傾斜し、第２の周壁部４は基準角からの角度２０〜４０°（例えば、２０〜３０°）で第１のヒンジ部７から容器の内方へ傾斜している。また、開口部に向かって、第３の周壁部５は基準角からの角度９０〜１１０°で第２のヒンジ部８から容器の内方へ傾斜している。すなわち、第３の周壁部５は、底壁１の方向にいくにつれて、底壁１面に対して角度０〜２０°でほぼ平行乃至緩やかに内方に傾斜している。第４の周壁部６は、底壁１からほぼ立設しており、開口部に向かって、基準角からの角度５〜１５°で容器の外方へ傾斜している。
【００２３】
このような収縮又は圧縮状態の容器は、伸長操作及び収縮操作により可逆的に伸縮（拡張又は縮小）可能であり、開口部側の周壁部３に対して底壁側の周壁部４，５が相対的に折返し可能である。すなわち、収縮又は圧縮状態の容器の開口部側から底壁１側に第３の周壁部５や底壁１などを押圧し又は押下げると、周壁部４，５，６に周方向の応力を吸収可能な縦襞（伸縮襞）１０，１１，１２が形成され、かつ第２の周壁部４及び第３の周壁部５が容器の内方側へ傾斜しているため、第４の周壁部６及び底壁１の下降に伴って、第２の周壁部４及び第３の周壁部５が漸次屈曲して円滑に展開又は折返することができる。特に、第２の周壁部４が第１の周壁部３側に湾曲していないため、比較的小さな押し下げ力で第２の周壁部４及び第３の周壁部５を円滑に展開又は折返することができ、伸長又は拡張した容器を形成できる。さらに、伸長又は展開状態では、第１のヒンジ部７が環状細幅の平滑部として形成されているため、容器の形態を円筒状の形態に保持できる。このような容器において、前記第１の周壁部３〜第３の周壁部５は、底壁１から開口部側に向かって段階的に径大となって傾斜している。
【００２４】
さらに、収縮した容器内に第１の周壁部と第３の周壁部とが収容された状態となるため、伸長操作により、収縮又は圧縮状態から高さを２倍以上（特に２〜３倍程度）に大きくできる。
【００２５】
一方、伸長（又は展開）状態の容器において、底壁１などを押入すると、第２のヒンジ部８が線状であり、かつ縦襞１０，１１が連続して延びているため、第４の周壁部６及び底壁１の下降（又は開口部側への侵入動）に伴って、第２の周壁部４及び第３の周壁部５が容器又は第１の周壁部３内に円滑に折り込まれ、圧縮状態のコンパクトな容器を形成できる。
【００２６】
なお、本発明の容器は、底壁と、この底壁から開口部に向かって形成された筒状の側壁とで構成されており、底壁及び側壁は、複数の周壁部が容器内に折り込み及び折返しが可能である限り、円形状又は円筒状に限らず、楕円状又は楕円筒状、多角形状（例えば、６角形状〜２４角形状など）又は多角筒状であってもよい。底壁及び側壁は、通常、円形状又は円筒状、楕円状又は楕円筒状に形成されている。また、底壁は必ずしも環状凹部を備えている必要はなく平坦壁で構成してもよく、適所に凹部やリブなどを備えていてもよい。
【００２７】
複数の周壁部で構成された前記側壁は、全体として外方に連続的に傾斜していてもよいが、通常、複数の周壁部とヒンジ部とにより段階的に傾斜している。なお、各周壁部は、通常、直線状に形成されている場合が多いものの、容器の内方又は外方に湾曲していてもよい。
【００２８】
前記側壁は、屈曲可能な複数のヒンジ部を介して、容器の縦方向又は半径方向に複数の周壁部（環状壁部）を備えている。前記側壁は、開口部側の上周壁部と、底壁側の下周壁部と、前記上周壁部と下周壁部との間に介在する少なくとも１つの中間周壁部（例えば、複数の中間周壁部）とで構成すればよい。すなわち、側壁は少なくとも３つの周壁部（例えば、４〜８、特に４〜６程度の周壁部）で構成できる。側壁は、通常、少なくとも４つの周壁部（例えば、４〜８、特に４〜６程度の周壁部）で構成されている。
【００２９】
収縮した状態の容器では、前記中間周壁部のうち両側にヒンジ部が形成された前記中間周壁部は、容器をコンパクト化するとともに伸縮操作を円滑に行うため、通常、上周壁部側のヒンジ部から開口部側にいくにつれて内方に傾斜している。なお、伸長又は拡張した状態の容器で、通常、少なくとも前記中間周壁部及び上周壁部が底壁から開口部側に向かって段階的に径大となって傾斜しており、下周壁部も含めて側壁が開口部側に向かって段階的に径大となって傾斜してもよい。
【００３０】
また、収縮又は圧縮状態において、複数の中間周壁部と下周壁部とは、開口部に向かって、開口部側が狭まった（又は径小である）断面山形の多角形状、例えば、断面台形状（又はブリッジ状）、逆Ｕ字状やアーチ状などの形状であってもよい。例えば、収縮した容器において、上周壁部や第１の周壁部は開口部から底壁に向かって容器の内方に傾斜し、中間周壁部や第２の周壁部は第１のヒンジ部から開口部に向かって容器の内方に傾斜し、後続する中間周壁部や第３の周壁部は第２のヒンジ部から実質的に横方向に延出していてもよい。
【００３１】
前記各周壁部の長さや角度は、コンパクト化や伸長及び収縮操作を損なわない限り適当に選択できる。収縮状態において、各周壁部の長さは、例えば、上周壁部又は第１の周壁部の長さを基準長さ「１」としたとき、複数の中間周壁部（又は第２の周壁部）の長さは、それぞれ、基準長に対して０．２〜１．５（好ましくは０．３〜１）程度の範囲から選択でき、下周壁部又は第４の周壁部の長さは、基準長に対して０．５〜１．５（好ましくは０．５〜１．２、さらに好ましくは０．６〜１）程度である。なお、第２の周壁部の長さは、基準長に対して０．５〜１．５（好ましくは０．５〜１．２、さらに好ましくは０．６〜１）程度、第３の周壁部の長さは、基準長に対して０．２〜１（好ましくは０．３〜０．８）程度である。各周壁部（特に複数の中間周壁部や第２乃至第３の周壁部）の長さは、伸長又は展開状態での容器の高さをも規定する。
【００３２】
収縮状態において、底壁面に対する垂直角を基準角としたとき、例えば、少なくとも１つの中間周壁部が基準角からの角度１０〜６０°（好ましくは１５〜４５°、さらに好ましくは２０〜４０°）で開口部に向かって内方へ傾斜し、前記下周壁部側の中間周壁部が実質的に横方向、例えば、基準角から角度６０〜１２０°（好ましくは７０〜１１０°、さらに好ましくは８５〜１０５°）で内方へ傾斜している。より具体的には、図示する例において、収縮又は成形した状態の容器において、底壁面に対する垂直角を基準角としたとき、第１の周壁部（上周壁部）は基準角からの角度５〜３０°（好ましくは５〜２０°、さらに好ましくは５〜１５°）で開口部に向かって外方へ傾斜し、第２の周壁部は基準角からの角度１０〜６０°（好ましくは１０〜５０°、さらに好ましくは１５〜４０°、特に１５〜３０°（例えば２０〜３０°）程度）で開口部に向かって内方へ傾斜し、第３の周壁部は基準角からの角度６０〜１２０°（好ましくは７０〜１１０°、さらに好ましくは９０〜１１０°）で横方向又は開口部に向かって内方へ傾斜している。第４の周壁部（下周壁部）は、基準角からの角度５〜３０°（好ましくは５〜２０°、さらに好ましくは５〜１５°）で底壁１から開口部に向かって外方へ傾斜している。なお、前記基準角に対する第２の周壁部の傾斜角度が大きすぎると、伸長操作により縦長の容器が形成され、安定性が低下する場合があり、第２の周壁部４の傾斜角度が小さすぎると、大きな伸長力を必要とする場合がある。
【００３３】
なお、開口部側の上周壁部には、補強性及び形状保持性を高めるため、前記環状段部や開口周縁部の折返し部と共に又は環状段部や折返し部に代えて、周方向に延びる補強リブを形成してもよい。
【００３４】
前記複数の中間周壁部のうち、少なくとも１つの中間周壁部の両側にはヒンジ部が形成されており、隣接する複数の中間周壁部の間にヒンジ部を介在させ、介在するヒンジ部で隣接する複数の中間周壁部を屈曲可能に連結してもよい。中間周壁部の数は特に制限されず、例えば、２〜４程度であってもよい。さらに、ヒンジ部は薄肉部として形成してもよい。
【００３５】
なお、両側にヒンジ部が形成された中間周壁部のうち、上周壁部側（又は開口部側）のヒンジ部（例えば、前記第１のヒンジ部）は、断面Ｖ字状やＵ字状などの切欠又は切り込み凹部により線状（例えば、薄肉で線状）に形成してもよいが、容器の形状を保持させるため、所定幅（特に平滑又は湾曲した所定幅）に形成するのが好ましい。上記ヒンジ部の幅は、容器のサイズなどにより変化するが、通常、０．１〜０．５ｍｍ程度であってもよい。特に、縦襞（伸縮襞又は収縮襞）は隣接する周壁部から上記ヒンジ部（例えば、前記第１のヒンジ部）を横断していてもよいが、横断することなく、ヒンジ部で途切れているのが好ましい。さらに、両側にヒンジ部が形成された中間周壁部のうち、下周壁部側（又は底壁側）のヒンジ部（例えば、前記第２のヒンジ部）は、細幅に形成してもよいが、屈曲性を高めるため、断面Ｖ字状やＵ字状などの切欠又は切り込み凹部により線状（切欠などにより形成された薄肉の線状）に形成するのが有利である。特に、上記ヒンジ部（第２のヒンジ部）では縦襞が途切れていてもよいが、上記ヒンジ部（第２のヒンジ部）では縦襞が隣接する周壁部から連続して形成又は横断しているのが好ましい。
【００３６】
さらに、上記ヒンジ部（第２のヒンジ部）には、屈曲可能な補強部を形成してもよい。図５は本発明の伸縮性容器（収縮状態）の他の例を示す概略斜視図であり、図６は図５の伸縮性容器を示す部分端面図である。なお、前記図１に示す容器と同様の部材又は要素には同一符号を付して説明する。
【００３７】
この例では、展開又は伸長状態での容器の形状を環状に整えるため、第２のヒンジ部は断面凸状の環状リブ１８として形成されている。そのため、第２のヒンジ部では環状リブ１８により縦襞１０，１１が途切れている。このような容器では、前記環状リブ１８により展開状態での強度を高めることができるだけでなく、環状の形態を保持でき、外観を向上させることもできる。
【００３８】
なお、上記環状リブは、展開状態で環状の形態を維持できる限り、断面凸状である必要はなく、断面凹状であってもよく、断面湾曲状や厚肉状であってもよい。さらに、第２のヒンジ部には、全周に亘り環状リブ部を形成する必要はなく、所定間隔毎に補強部を形成してもよい。
【００３９】
前記縦襞（収縮襞）は、容器の縦方向又は半径方向の同一線上に沿って（位置ずれすることなく）周方向に互いに隣接して形成されている。また、縦襞は、通常、開口部方向に向かって幅広の放射状に形成されている。なお、縦襞の幅や深さは、容器の開口部の径などに応じて伸縮性を損なわない範囲から選択でき、通常、幅１〜１０ｍｍ（好ましくは１．５〜５ｍｍ、特に２〜５ｍｍ）程度の範囲から選択でき、深さ０．２〜３ｍｍ（好ましくは０．５〜２ｍｍ）程度の範囲から選択できる。
【００４０】
縦襞は、全ての周壁部に形成してもよいが、少なくとも屈曲に伴って応力が作用する領域（又はこの領域を含む周壁部やヒンジ部に隣接する周壁部）、例えば、少なくとも中間周壁部や第２の周壁部及び第３の周壁部に形成するのが好ましい。なお、第４の周壁部にも全体に亘り縦襞を形成してもよいが、第４の周壁部のうち、第３のヒンジ部に隣接し、かつ屈曲応力が作用する領域に縦襞を形成してもよい。
【００４１】
前記のように、本発明の容器は、非発泡樹脂シートを容器成形しても、前記開口部側の周壁部に対して底壁側の周壁部が相対的に折返し可能であるとともに、開口部側の周壁部内（又は容器内）に底壁側の周壁部を折り込んで（又は折り畳んで）収容可能である。特に、図１及び図２に示すように、非発泡樹脂シートを圧縮又は収縮形態の容器に成形し、使用に際して、伸長操作により容積が収縮状態よりも２倍以上大きな容器の形態に拡張できる。そのため、大きな容積の容器を成形した後、圧縮してコンパクト化する必要がなく、容器の生産性を高めることができるとともに、収納スペースを小さくでき、輸送又は保管コストを大きく低減できる。
【００４２】
そのため、本発明は前記容器の製造方法も含む。この方法では、樹脂シートの成形（シートの容器成形）により、前記構造の伸縮性容器を製造する。この方法において、例えば、樹脂シートの成形により、底壁と、この底壁から開口部に向かって全体として外方に傾斜した周壁部を備えた側壁とで構成され、かつ前記開口部側の周壁部に対して底壁側の周壁部が相対的に収縮状態から伸長可能な容器を製造する。容器の成形においては、伸長又は拡張状態の容器を成形した後、収縮させてコンパクト化してもよいが、生産性の点からは、収縮又は圧縮状態で容器を成形するのが有利である。
【００４３】
さらに、成形性の観点から、上周壁部は、通常、開口部にいくにつれて基準角を越えて容器の内方に傾斜することはなく、開口部にいくにつれて前記のような角度で容器の外方に傾斜している。また、複数の中間周壁部と下周壁部とは、通常、開口部側が狭まった形状、例えば、断面台形状（又はブリッジ状）、山形の多角形状（若しくは逆Ｕ字状やアーチ状）に形成されている。具体的には、各周壁部は前記の角度で形成されている。そして、シートの容器成形において、容器の内方に位置する周壁部が開口部側に向かって狭まっているため、収縮又は圧縮状態の容器を加熱圧縮成形などの成形法により簡便かつ効率よく製造できる。
【００４４】
なお、シートの成形加工では、前記ヒンジ構造及び縦襞を有する複数の周壁部を形成すればよい。すなわち、屈曲可能な複数のヒンジ部を介して半径方向に複数の周壁域（前記上下周壁部及び複数の中間周壁部や、第１乃至第４の周壁部に対応する領域）を備え、かつ前記複数の周壁域（特に少なくともヒンジ部の両側に隣接する複数の周壁部）に、半径方向の同一線上に沿って延びる縦襞を互いに隣接して形成することにより、収縮状態の容器を成形できる。
【００４５】
本発明の容器は、発泡樹脂シート（発泡倍率１．１〜３倍程度の発泡樹脂シートなど）や非発泡樹脂シートのいずれで形成してもよいが、薄くても剛性を高めるため、非発泡樹脂シートで形成できる。樹脂シートとしては、熱可塑性樹脂シート、例えば、ポリオレフィン系樹脂シート（ポリプロピレン系樹脂シートなど）、スチレン系樹脂シート、ハロゲン化ビニル系樹脂シート（塩化ビニル系樹脂シート）、ポリエステル系樹脂シート（ポリエチレンテレフタレートやポリブチレンテレフタレートなどのポリアルキレンアリレート系樹脂やポリアルキレンアリレート系コポリエステルなど）などが例示できる。これらの樹脂シートは必要により一軸又は二軸延伸されていてもよい。スチレン系樹脂シートは、ポリスチレン系樹脂、ポリスチレン系樹脂と軟質樹脂（耐衝撃性ポリスチレン又はゴムグラフトスチレン系樹脂、スチレン−ジエン共重合体、熱可塑性エラストマーなどから選択された少なくとも一種の軟質樹脂）とで構成されたスチレン系樹脂組成物で形成できる。樹脂シートの厚みは特に制限されず、例えば、０．１〜２ｍｍ、好ましくは０．２〜１．５ｍｍ、特に０．３〜１ｍｍ程度であってもよい。
【００４６】
シートの容器成形は、慣用の方法、例えば、真空成形、吹き込み成形、圧空成形、マッチドモールド成形などの熱成形法を利用して行うことができる。
【００４７】
なお、本発明の容器は、容器の開口部を開閉可能な蓋体を有していてもよい。蓋体を備えた容器では、開口部の周縁部に蓋体が脱着可能な嵌合部を形成してもよい。
【００４８】
本発明の容器（又は包装用容器）は、コンパクトで携帯性又は輸送性が高く、しかも使用に際しては容積が大きな容器の形態に復元できるため、種々の容器、例えば、コップ類、カップ類などに広く利用できる。また、携帯容器としても利用できる。
【００４９】
【発明の効果】
本発明では、複数のヒンジ部と縦襞とが形成された複数の周壁部を有するため、可逆的に伸縮可能であり、かつ伸長操作により所定形状の容器を形成できる。また、非発泡樹脂シートで形成しても、伸縮操作により円滑に伸長又は収縮できるとともに、収縮状態よりも２倍以上の高さに伸張できる。さらに、本発明の伸縮性容器は、シートから収縮又は圧縮状態のコンパクトな容器を成形できるとともに、使用に際して容積の大きな容器の形態に円滑に伸長又は拡張でき、伸縮性容器の生産性を高めることができる。
【図面の簡単な説明】
【図１】図１は本発明の伸縮性容器の一例を示す概略斜視図である。
【図２】図２は図１の伸縮性容器を示す部分端面図である。
【図３】図３は図１の伸縮性容器の伸長状態を示す概略斜視図である。
【図４】図４は図３の伸縮性容器を示す部分端面図である。
【図５】図５は本発明の伸縮性容器（収縮状態）の他の例を示す概略斜視図である。
【図６】図６は図５の伸縮性容器を示す部分端面図である。
【符号の説明】
１…底壁
２…側壁
３…第１の周壁部
４…第２の周壁部
５…第３の周壁部
６…第４の周壁部
７…第１のヒンジ部
８…第２のヒンジ部
１０，１１，１２…縦襞
１８…環状リブ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a stretchable container that can be reversibly stretched from a compact contracted or compressed state to a container form when used, and a method for producing the same.
[0002]
[Prior art]
2. Description of the Related Art A container having a bottom wall and a bellows-shaped cylinder extending from the bottom wall is known as an elastic container. This container is made compact by forming an elongated cylindrical body into a bellows shape and contracting in the axial direction during the distribution process. However, in the state where the bellows-shaped cylinder is contracted, stress or stress concentrates on the bent portion. Therefore, when stored for a long time, there is a high possibility that a pinhole or a crack is generated in the bent portion. Furthermore, since the container is compacted by being contracted from the extended state, it is difficult to improve the productivity. In particular, in a bellows-shaped cylinder having a high resilience to shrinkage, it is necessary to maintain the container in a compressed state in order to maintain a contracted state. Furthermore, in order to maintain appropriate strength, the thickness of the container must be relatively thick, which is economically disadvantageous.
[0003]
Japanese Utility Model Publication No. 5-40843 discloses that a cup-shaped container main body and ground coffee connected via a step portion beside the container main body are stored, and a coffee storage portion having a smaller diameter than the container main body is thinned. A coffee extractor formed of a synthetic resin, wherein a vertical fold is provided on a peripheral surface of a lower half of the container body, a fold line is formed on an upper edge of the vertical fold, and a ring is formed from an outer peripheral edge of a step portion. A coffee extractor (or a coffee extractor) in which a concave groove portion is provided, and the peripheral surface portion provided with the vertical folds is folded into the inside of the container main body from a fold line of an upper edge thereof to store the coffee storing portion in the upper inner peripheral surface portion of the container main body (or Container) is disclosed. In this container, the coffee storage part can be stored compactly, and at the time of use, the coffee storage part is pushed downward from the container body and can be used as a coffee extractor. However, in this container, since the storage portion is stored in the container main body, it is difficult to reduce the height in the contracted state to 以下 or less as compared with the state where the storage portion is extended. Therefore, there is a limit in reducing the volume, and it is difficult to further reduce the transportation cost and the storage cost.
[0004]
Japanese Patent No. 3051331 discloses a lower member having a bottom surface portion, a lower circumferential surface portion formed in an inclined shape having a large upper portion, an upper end of the lower circumferential surface portion, and a first hinge. An intermediate member having an intermediate peripheral portion integrally connected in an inclined manner such that the lower portion has a large diameter at the lower portion on the outer lower side through the portion; and an upper portion on the outer upper side via the lower end of the intermediate circumferential surface portion and the second hinge portion. There is disclosed an extendable container including an upper member having an upper circumferential surface portion integrally connected in an inclined shape having a large diameter. In this container, the lower circumferential surface portion and the intermediate circumferential surface portion are respectively formed with radial expansion / contraction grooves in the vertical direction on the inner surface side without being exposed on the outer surface side, and the intermediate member is formed of the first member. By inverting and extending upward through the hinge portion and the second hinge portion, the extended intermediate circumferential surface portion forms a container side wall surface that is substantially continuous with the lower circumferential surface portion and the upper circumferential surface portion.
[0005]
In this container, the radial expansion / contraction groove portion facilitates inversion of the intermediate member, and the intermediate circumferential surface portion formed on the curved surface expanding toward the inside of the container along with the contraction operation expands outward along with the upward inversion. Because it becomes a curved surface, you can strengthen your waist. In addition, since the expansion / contraction grooves are formed on the inner surface side of the lower circumferential surface portion and the intermediate circumferential surface portion, a large tension acts on the outer surface side in accordance with the reversing operation. Therefore, a large force is required to expand the contracted container by the reversing operation, and the expanded container cannot be formed smoothly. In particular, when a container is formed using a non-foamed resin sheet, a large reversing force is required for the stretching operation.
[0006]
Japanese Unexamined Patent Publication No. Hei 6-508590 discloses that in a three-dimensionally shaped container formed of concentric rings, a plurality of concentric annular walls are arranged following a bottom portion, and an annular area of a very thin wall is formed. A container is disclosed in which adjacent and inclined walls are connected to each other via a hinge. In this container, the greatly inclined annular wall is folded over the adjacent wall to fold the container. Therefore, a compact container can be formed. However, when the volume of the container is reduced by folding the annular wall portion, a large stress acts on the hinge portion, and the hinge portion may be damaged. In particular, when the depth of the container is increased, a large expansion force and a large contraction force are applied to the hinge portion in association with the folding operation, so that it is difficult to fold the annular fold even using the hinge portion.
[0007]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide a stretchable container that is reversibly expandable and contractable and can form a container having a predetermined shape by an extension operation, and a method for manufacturing the same.
[0008]
Another object of the present invention is to provide a stretchable container which can be smoothly stretched or contracted by a stretching operation even when formed of a non-foamed resin sheet, and which can be stretched to a height twice or more as high as a contracted state, and a method for producing the same. To provide.
[0009]
Still another object of the present invention is to provide a stretchable container which can be formed into a compact container from a sheet and which can be smoothly extended into a large-volume container in use, and which can be manufactured with high productivity. It is to provide a method.
[0010]
[Means for Solving the Problems]
The present inventors have conducted intensive studies to achieve the above object, and as a result of molding a container from a resin sheet, when an extensible container is molded in a contracted compact form, the productivity of an elastic container can be greatly improved. In forming a container, a plurality of peripheral walls that gradually increase in diameter toward the opening side through a plurality of hinges are formed, and when longitudinal folds are formed in the circumferential direction of these peripheral walls, the container smoothly extends. (Or unfolded) and found that a shrinkable container was obtained, and completed the present invention.
[0011]
That is, the elastic container of the present invention includes a bottom wall and side walls which are inclined outward as a whole from the bottom wall toward the opening. And in the said container, the said side wall is provided with the several peripheral wall part in the vertical direction via the several hinge part which can be bent, and along a plurality of peripheral wall parts along the same line in a vertical direction (in other words, Vertical folds are formed adjacent to each other (without displacement), and the peripheral wall on the bottom wall can be folded back relative to the peripheral wall on the opening side. In other words, by the extension operation, the bottom wall side peripheral wall portion is retracted with respect to the opening side peripheral wall portion to expand or expand, and with the contraction operation, the bottom wall side peripheral wall portion closes to the opening side. It can be contracted (or accommodated) by advancing or entering the peripheral wall portion. The side wall may be continuously increased in diameter and inclined toward the opening, but is usually increased in a stepwise manner and inclined by the plurality of peripheral wall portions. In addition, each peripheral wall may be gradually larger in diameter toward the opening.
[0012]
In the container, the side wall may include an upper peripheral wall on the opening side, a lower peripheral wall on the bottom wall, and a plurality of intermediate peripheral walls interposed between the upper peripheral wall and the lower peripheral wall, Hinge portions are formed on both sides of at least one intermediate peripheral wall portion. In a container having such a side wall, in a contracted state, the plurality of intermediate peripheral walls and the lower peripheral wall have a polygonal cross-section toward the opening (for example, a bridge-shaped cross-section or a polygonal-bridged cross-section). In the extended state, the intermediate peripheral wall and the upper peripheral wall may be gradually increased in diameter from the bottom wall toward the opening and inclined. More specifically, the side wall includes a first peripheral wall portion inclined inward from the opening toward the bottom wall, and an inward direction from the first peripheral wall portion toward the opening via the first hinge portion. A second peripheral wall portion inclined to the second peripheral wall portion, a third peripheral wall portion extending laterally from the second peripheral wall portion via a second hinge portion, and a fourth peripheral wall portion extending from the third peripheral wall portion to the bottom wall. A peripheral wall portion may be provided.
[0013]
In such a container, in a contracted state, when a vertical angle with respect to the bottom wall surface is set as a reference angle, at least one intermediate peripheral wall portion is inclined inward at an angle of 10 to 60 ° from the reference angle toward the opening. The intermediate peripheral wall on the side of the lower peripheral wall may extend in the lateral direction (or inclined inward at an angle of 60 to 120 ° from the reference angle). For example, in a contracted state, the first peripheral wall portion inclines inward from the opening toward the bottom wall, and the second peripheral wall portion inclines inward from the first hinge portion toward the opening. The third peripheral wall may extend substantially laterally from the second hinge. More specifically, in a contracted state, when a vertical angle with respect to the bottom wall surface is set as a reference angle, the first peripheral wall portion is inclined outward toward the opening at an angle of 5 to 30 ° from the reference angle, The second peripheral wall may be inclined inward at an angle of 10 to 50 degrees from the reference angle toward the opening, and the third peripheral wall may extend laterally at an angle of 70 to 110 degrees from the reference angle. .
[0014]
Further, vertical folds may be formed at least on the second peripheral wall portion and the third peripheral wall portion adjacent to each other, and the first hinge portion may be formed to have a predetermined width (narrow width). Further, a boundary area (second hinge part) between the second peripheral wall part and the third peripheral wall part may be formed in a linear shape (for example, a bent curve shape), and may be formed in an annular rib (a convex shape or a convex shape). It may be formed as a concave annular rib. Note that the first hinge portion may be formed as a smooth portion. The vertical fold may be formed along the same line extending in the radial direction or the radial direction. The vertical fold may have a hinge portion (for example, a hinge portion on the opening side such as the first hinge portion) in order to enhance reinforcement. ), And the vertical fold may be formed continuously at a hinge portion (for example, a hinge portion on the bottom wall side such as the second hinge portion) in order to increase flexibility. The longitudinal folds are generally capable of absorbing circumferential stress by expansion and contraction in the circumferential direction. Such longitudinal folds may be formed radially. For example, the width of the vertical folds adjacent in the circumferential direction may be formed wider (for example, gradually wider) toward the opening.
[0015]
Note that, in order to enhance the reinforcing property, the upper peripheral wall portion on the opening side may include a plurality of annular steps that increase in diameter toward the opening, and may have a folded portion on the peripheral edge of the opening. The stretchable container of the present invention can smoothly perform stretching and shrinking operations even when formed of a non-foamed resin sheet.
[0016]
In the method of the present invention, a resin sheet (non-foamed or foamed resin sheet) is formed to produce a stretchable container having the above structure. In this method, for example, a resin sheet is formed, and is formed of a bottom wall, and a side wall having a peripheral wall portion that is inclined outward as a whole from the bottom wall toward the opening, and the peripheral wall on the opening side is formed. The container is manufactured such that the peripheral wall portion on the bottom wall side with respect to the portion can be extended from the contracted state. In such a method, by forming the sheet, the plurality of peripheral wall regions are radially extended through the plurality of bendable hinge portions, and the plurality of peripheral wall regions extend along the same line in the radial direction. By forming vertical folds adjacent to each other in a direction to form a container in a contracted state, a stretchable container can be manufactured.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings as necessary.
[0018]
FIG. 1 is a schematic perspective view showing an example of the elastic container of the present invention, and FIG. 2 is a partial end view showing the elastic container of FIG. FIG. 3 is a schematic perspective view showing an extended state of the elastic container of FIG. 1, and FIG. 4 is a partial end view showing the elastic container of FIG.
[0019]
As shown in FIGS. 1 and 2, the elastic container is formed in a contracted or compressed state by molding a non-foamed resin sheet into a container. The container includes a circular bottom wall 1 having an annular concave portion 1a formed at a peripheral edge thereof, and a concentric side wall 2 extending vertically from the bottom wall. The side wall 2 is composed of a plurality of peripheral wall portions 3 to 6, and has a diameter gradually increasing toward the opening as a whole and inclining outward. That is, as shown in FIGS. 3 and 4, the side wall 2 has a first peripheral wall portion 3 that is inclined inward from the opening toward the bottom wall, and a first peripheral wall portion that extends from the first peripheral wall portion toward the opening. A second peripheral wall 4 inclined inward, a third peripheral wall 5 extending laterally from the second peripheral wall, and a fourth peripheral wall extending from the third peripheral wall 5 to the bottom wall 1 The angle of the first peripheral wall portion 3, the second peripheral wall portion 4, and the third peripheral wall portion 5 is gradually reduced toward the bottom wall 1 side. The first peripheral wall 3 on the side of the opening includes a plurality of annular steps 3a, 3b, 3c that increase in diameter toward the opening in order to enhance the reinforcing properties, and the peripheral edge of the opening has It has a folded part 3d.
[0020]
A plurality of bendable hinge portions are formed on the side wall 2. In this example, hinge portions are formed on both sides of the second peripheral wall portion 4. That is, the first hinge portion 7 is interposed between the first peripheral wall portion 3 and the second peripheral wall portion 4, and the first hinge portion 7 is interposed between the second peripheral wall portion 4 and the third peripheral wall portion 5. The second hinge portion 8 is interposed. In addition, a boundary area between the third peripheral wall 5 and the fourth peripheral wall 6 also functions as a third hinge 9 that can be bent. The first hinge portion 7 has a smooth narrow width (for example, a width of about 0.1 to 0.5 mm) in order to hold the first peripheral wall portion 3 in an annular shape while the container is extended. The second hinge portion 8 is formed in a linear shape (or a bent linear shape) in order to smoothly fold or invert the third peripheral wall portion 5 inward (or the opening side) by a contracting operation. I have.
[0021]
Furthermore, in order to impart elasticity in the circumferential direction and absorb circumferential stress accompanying extension (or unfolding) and contraction operations, longitudinal folds are formed adjacent to each other in the circumferential direction of the plurality of peripheral walls. I have. That is, the peripheral wall portions (the second peripheral wall portion 4, the third peripheral wall portion 5, and the fourth peripheral wall portion 6) except for the first peripheral wall portion 3 respectively extend along the same line in the vertical or radial direction. A number of longitudinal folds 10, 11, 12 extending in the longitudinal or radial direction without displacement are formed adjacent to each other in the circumferential direction. Further, in the extended state or the expanded state, the vertical fold 10 is interrupted in the first hinge portion 7 in order to provide reinforcement and maintain the shape in a circular shape. On the other hand, longitudinal folds 10 and 11 are formed continuously in the second hinge portion 8 in order to enhance the flexibility and contractibility (or folding property). The width of the vertical folds 10 to 12 adjacent in the circumferential direction is formed radially, that is, gradually wider toward the opening. In addition, the vertical fold forms a concavo-convex peripheral wall portion having a substantially uniform thickness, and functions as a circumferential fold in the inner and outer surfaces of the peripheral wall portion.
[0022]
As shown in FIGS. 1 and 2, the container in such a contracted or molded state is provided inside the first peripheral wall 3, the second peripheral wall 4, the third peripheral wall 5, and the fourth peripheral wall 6. Is accommodated, and the second to fourth peripheral walls 4 to 6 are formed in a trapezoidal shape (or a bridge shape or a polygonal bridge shape) having a mountain-shaped cross section toward the opening. . That is, the second peripheral wall portion 4 is inclined inward as it goes from the first hinge portion 7 to the opening side, and the third peripheral wall portion 5 becomes the second hinge portion in the contracted or molded container. 8 extends substantially laterally from the second peripheral wall part 4 via 8. More specifically, as shown in FIG. 2, in a contracted or molded state, when a vertical angle with respect to the bottom wall 1 is set as a reference angle, the first peripheral wall portion 3 moves from the reference angle toward the opening. At an angle of 5 to 15 ° from the first hinge portion 7 to the outside of the container, and the second peripheral wall portion 4 is at a first angle of 20 to 40 ° (eg, 20 to 30 °) from the reference angle. It is inclined from the hinge part 7 to the inside of the container. Further, toward the opening, the third peripheral wall 5 is inclined from the second hinge 8 to the inside of the container at an angle of 90 to 110 ° from the reference angle. That is, the third peripheral wall portion 5 is inclined substantially parallel to the inner surface at an angle of 0 to 20 ° with respect to the surface of the bottom wall 1 as it goes in the direction of the bottom wall 1. The fourth peripheral wall portion 6 is substantially erected from the bottom wall 1 and is inclined outward from the container at an angle of 5 to 15 degrees from the reference angle toward the opening.
[0023]
The container in such a contracted or compressed state can be reversibly expanded and contracted (expanded or reduced) by an extension operation and a contraction operation, and the peripheral wall portions 4 and 5 on the bottom wall side are different from the peripheral wall portion 3 on the opening side. It can be folded relatively. That is, when the third peripheral wall 5 and the bottom wall 1 are pressed or pushed down from the opening side of the container in the contracted or compressed state toward the bottom wall 1, circumferential stress is applied to the peripheral walls 4, 5 and 6. Since the absorbable longitudinal folds (elastic folds) 10, 11, and 12 are formed and the second peripheral wall 4 and the third peripheral wall 5 are inclined inward of the container, the fourth peripheral wall is formed. With the lowering of the bottom wall 6 and the bottom wall 1, the second peripheral wall portion 4 and the third peripheral wall portion 5 can be gradually bent and smoothly deployed or folded. In particular, since the second peripheral wall portion 4 is not curved toward the first peripheral wall portion 3, the second peripheral wall portion 4 and the third peripheral wall portion 5 can be smoothly developed or folded with a relatively small pressing force. To form an elongated or expanded container. Further, in the extended or unfolded state, the first hinge portion 7 is formed as a smooth portion having an annular narrow width, so that the shape of the container can be maintained in a cylindrical shape. In such a container, the first peripheral wall portion 3 to the third peripheral wall portion 5 gradually increase in diameter from the bottom wall 1 toward the opening side and are inclined.
[0024]
Further, since the first peripheral wall portion and the third peripheral wall portion are housed in the contracted container, the height is more than doubled (particularly about 2-3 times) from the contracted or compressed state by the extension operation. ).
[0025]
On the other hand, when the bottom wall 1 or the like is pushed in the container in the extended (or unfolded) state, the second hinge portion 8 is linear and the vertical folds 10 and 11 are continuously extended. As the peripheral wall portion 6 and the bottom wall 1 descend (or move inward to the opening side), the second peripheral wall portion 4 and the third peripheral wall portion 5 are smoothly folded into the container or the first peripheral wall portion 3. Thus, a compact container in a compressed state can be formed.
[0026]
The container of the present invention includes a bottom wall and a cylindrical side wall formed from the bottom wall toward the opening, and the bottom wall and the side wall have a plurality of peripheral wall portions folded into the container. As long as folding is possible, the shape is not limited to a circular shape or a cylindrical shape, but may be an elliptical shape, an elliptical cylindrical shape, a polygonal shape (for example, a hexagonal shape to a 24-sided shape), or a polygonal cylindrical shape. The bottom wall and the side wall are usually formed in a circular or cylindrical shape, an elliptical shape, or an elliptical cylindrical shape. Further, the bottom wall does not necessarily have to have the annular concave portion, and may be formed of a flat wall, and may have a concave portion, a rib, or the like in an appropriate position.
[0027]
The side wall constituted by the plurality of peripheral wall portions may be continuously inclined outward as a whole, but is generally inclined stepwise by the plurality of peripheral wall portions and the hinge portion. In addition, although each peripheral wall portion is usually formed in a linear shape in many cases, it may be curved inward or outward of the container.
[0028]
The side wall is provided with a plurality of peripheral wall portions (annular wall portions) in a longitudinal direction or a radial direction of the container via a plurality of bendable hinge portions. The side wall includes an upper peripheral wall on an opening side, a lower peripheral wall on a bottom wall, and at least one intermediate peripheral wall (for example, a plurality of intermediate peripheral walls) interposed between the upper peripheral wall and the lower peripheral wall. What is necessary is just to comprise. That is, the side wall can be constituted by at least three peripheral wall parts (for example, about 4 to 8, especially about 4 to 6 peripheral wall parts). The side wall is generally constituted by at least four peripheral wall portions (for example, 4 to 8, especially 4 to 6 peripheral wall portions).
[0029]
In the container in a contracted state, the intermediate peripheral wall portion having hinge portions formed on both sides of the intermediate peripheral wall portion reduces the size of the container and smoothly performs expansion and contraction operations. It is inclined inward toward the opening. In the container in an extended or expanded state, usually, at least the intermediate peripheral wall and the upper peripheral wall gradually increase in diameter from the bottom wall toward the opening side and are inclined, and also include the lower peripheral wall. The side wall may be gradually increased in diameter and inclined toward the opening.
[0030]
In the contracted or compressed state, the plurality of intermediate peripheral wall portions and the lower peripheral wall portion have a polygonal shape having a mountain-shaped cross section with a narrower opening (or smaller diameter) toward the opening, for example, a trapezoidal cross section ( Or an inverted U-shape or an arch shape. For example, in a contracted container, the upper peripheral wall and the first peripheral wall are inclined inward of the container from the opening toward the bottom wall, and the intermediate peripheral wall and the second peripheral wall are opened from the first hinge. The intermediate peripheral wall portion and the third peripheral wall portion that incline toward the inside of the container and that extend therefrom may extend substantially laterally from the second hinge portion.
[0031]
The length and angle of each of the peripheral wall portions can be appropriately selected as long as they do not impair the compactness and the extension and contraction operations. In the contracted state, the length of each peripheral wall portion is, for example, when the length of the upper peripheral wall portion or the first peripheral wall portion is set to the reference length “1”, the length of each of the plurality of intermediate peripheral wall portions (or the second peripheral wall portion). Each length can be selected from a range of about 0.2 to 1.5 (preferably 0.3 to 1) with respect to the reference length, and the length of the lower peripheral wall portion or the fourth peripheral wall portion is the reference length. About 0.5 to 1.5 (preferably 0.5 to 1.2, and more preferably 0.6 to 1). The length of the second peripheral wall is about 0.5 to 1.5 (preferably 0.5 to 1.2, more preferably 0.6 to 1) with respect to the reference length, The length of the portion is about 0.2 to 1 (preferably 0.3 to 0.8) with respect to the reference length. The length of each peripheral wall (particularly, the plurality of intermediate peripheral walls and the second and third peripheral walls) also defines the height of the container in the extended or deployed state.
[0032]
In the contracted state, when a vertical angle with respect to the bottom wall surface is set as a reference angle, for example, at least one intermediate peripheral wall portion has an angle of 10 to 60 ° (preferably 15 to 45 °, more preferably 20 to 40 °) from the reference angle. And the intermediate peripheral wall portion on the side of the lower peripheral wall portion is substantially in a horizontal direction, for example, an angle of 60 to 120 ° (preferably 70 to 110 °, more preferably 85) from a reference angle. １０５105 °). More specifically, in the illustrated example, in a container in a contracted or molded state, when a vertical angle with respect to a bottom wall is set as a reference angle, the first peripheral wall (upper peripheral wall) is at an angle of 5 to 30 from the reference angle. ° (preferably 5 to 20 °, more preferably 5 to 15 °) and outwardly slope toward the opening, and the second peripheral wall is formed at an angle of 10 to 60 ° (preferably 10 to 50) from a reference angle. °, more preferably 15 to 40 °, particularly about 15 to 30 ° (for example, about 20 to 30 °), and the third peripheral wall is inclined at an angle of 60 to 120 from the reference angle. At an angle (preferably 70-110 °, more preferably 90-110 °), which slopes inward in the lateral direction or towards the opening. The fourth peripheral wall (lower peripheral wall) extends outward from the bottom wall 1 toward the opening at an angle of 5 to 30 ° (preferably 5 to 20 °, more preferably 5 to 15 °) from the reference angle. It is inclined. If the inclination angle of the second peripheral wall portion with respect to the reference angle is too large, a vertically long container may be formed by the elongating operation, and the stability may be reduced, and the inclination angle of the second peripheral wall portion 4 is too small. In some cases, a large extension force is required.
[0033]
In order to enhance the reinforcing property and the shape retaining property, the upper peripheral wall portion on the opening side has reinforcing ribs extending in the circumferential direction together with the annular step portion or the folded portion of the peripheral edge of the opening or instead of the annular step portion or the folded portion. May be formed.
[0034]
A hinge portion is formed on both sides of at least one intermediate peripheral wall portion of the plurality of intermediate peripheral wall portions, and a hinge portion is interposed between a plurality of adjacent intermediate peripheral wall portions, and the adjacent intermediate peripheral wall portions are adjacent to each other. A plurality of intermediate peripheral wall portions may be connected to bendable. The number of intermediate peripheral wall portions is not particularly limited, and may be, for example, about 2 to 4. Furthermore, the hinge part may be formed as a thin part.
[0035]
Note that, of the intermediate peripheral wall portions having hinge portions formed on both sides, the hinge portion (for example, the first hinge portion) on the upper peripheral wall side (or the opening side) has a V-shaped or U-shaped cross section. The cutout or cutout recess may be formed linearly (for example, thin and linear), but is preferably formed to have a predetermined width (particularly a smooth or curved predetermined width) in order to maintain the shape of the container. The width of the hinge part varies depending on the size of the container and the like, but may be generally about 0.1 to 0.5 mm. In particular, the vertical folds (stretch folds or contraction folds) may cross the hinge portion (for example, the first hinge portion) from an adjacent peripheral wall portion, but are interrupted at the hinge portion without crossing. Is preferred. Furthermore, the hinge portion (for example, the second hinge portion) on the lower peripheral wall side (or the bottom wall side) of the intermediate peripheral wall portion having the hinge portions formed on both sides may be formed to be narrow. In order to enhance the flexibility, it is advantageous to form a V-shaped or U-shaped notch or cut-out recess into a line (a thin line formed by a notch or the like). In particular, the vertical fold may be interrupted at the hinge portion (second hinge portion), but the vertical fold is formed or crossed continuously from the adjacent peripheral wall portion at the hinge portion (second hinge portion). Is preferred.
[0036]
Further, a bendable reinforcing portion may be formed on the hinge portion (second hinge portion). FIG. 5 is a schematic perspective view showing another example of the elastic container (in a contracted state) of the present invention, and FIG. 6 is a partial end view showing the elastic container of FIG. Note that the same members or elements as those of the container shown in FIG.
[0037]
In this example, the second hinge portion is formed as an annular rib 18 having a convex cross section in order to adjust the shape of the container in an expanded or extended state to an annular shape. Therefore, the vertical folds 10 and 11 are interrupted by the annular rib 18 in the second hinge portion. In such a container, not only the strength in the deployed state can be increased by the annular ribs 18, but also the annular shape can be maintained, and the appearance can be improved.
[0038]
The annular rib does not need to have a convex cross section as long as it can maintain an annular shape in a deployed state, and may have a concave cross section, a curved cross section, or a thick cross section. Further, it is not necessary to form an annular rib portion over the entire periphery of the second hinge portion, and a reinforcing portion may be formed at predetermined intervals.
[0039]
The longitudinal folds (contraction folds) are formed adjacent to each other in the circumferential direction (without displacement) along the same longitudinal or radial line of the container. In addition, the vertical fold is generally formed in a radial shape that is wider toward the opening. The width and depth of the vertical fold can be selected from a range that does not impair the elasticity according to the diameter of the opening of the container, and is usually 1 to 10 mm (preferably 1.5 to 5 mm, particularly 2 to 5 mm). ) And a depth of about 0.2 to 3 mm (preferably 0.5 to 2 mm).
[0040]
The vertical fold may be formed on all the peripheral walls, but at least a region where a stress acts upon bending (or a peripheral wall including this region or a peripheral wall adjacent to the hinge), for example, at least an intermediate peripheral wall And the second and third peripheral walls. Although the vertical fold may be formed entirely on the fourth peripheral wall, the vertical fold is formed in a region of the fourth peripheral wall adjacent to the third hinge portion and where a bending stress acts. It may be formed.
[0041]
As described above, even when the container of the present invention is formed of a non-foamed resin sheet, the peripheral wall portion on the bottom wall side can be folded back relative to the peripheral wall portion on the opening side, and the opening portion is formed. The peripheral wall portion on the bottom wall side can be folded (or folded) and accommodated in the peripheral wall portion on the side (or inside the container). In particular, as shown in FIGS. 1 and 2, a non-foamed resin sheet is formed into a container in a compressed or shrunk form, and when used, can be expanded to a form in which the volume is twice or more larger than the shrunk state by an elongating operation. Therefore, there is no need to compress and reduce the size of the container after molding the container having a large volume, thereby increasing the productivity of the container, reducing the storage space, and greatly reducing the transportation or storage cost.
[0042]
Therefore, the present invention also includes a method for manufacturing the container. In this method, a stretchable container having the above-described structure is manufactured by forming a resin sheet (forming a container of the sheet). In this method, for example, by forming a resin sheet, a bottom wall and a side wall having a peripheral wall portion that is inclined outward from the bottom wall as a whole toward the opening, and the peripheral wall on the opening side are formed. The container is manufactured such that the peripheral wall portion on the bottom wall side with respect to the portion can be extended from the contracted state. In molding the container, the container may be contracted and compacted after molding the container in the expanded or expanded state, but from the viewpoint of productivity, it is advantageous to mold the container in the contracted or compressed state.
[0043]
Further, from the viewpoint of moldability, the upper peripheral wall portion does not normally incline inward of the container beyond the reference angle as it goes to the opening, and the outside of the container at the angle as described above as it goes to the opening. It is inclined. Further, the plurality of intermediate peripheral wall portions and the lower peripheral wall portion are usually formed in a shape in which the opening side is narrowed, for example, a trapezoidal cross section (or a bridge shape), a polygonal shape of a mountain shape (or an inverted U shape or an arch shape). Have been. Specifically, each peripheral wall is formed at the above-mentioned angle. Then, in forming the container of the sheet, since the peripheral wall portion located inside the container is narrowed toward the opening side, the container in a contracted or compressed state can be easily and efficiently manufactured by a forming method such as heat compression molding. .
[0044]
In forming the sheet, a plurality of peripheral wall portions having the hinge structure and the vertical folds may be formed. That is, a plurality of peripheral wall regions (regions corresponding to the upper and lower peripheral wall portions, the plurality of intermediate peripheral wall portions, and the first to fourth peripheral wall portions) are provided in the radial direction via a plurality of bendable hinge portions, and By forming longitudinal folds extending along the same radial line adjacent to each other in a plurality of peripheral wall regions (particularly, at least a plurality of peripheral wall portions adjacent to both sides of the hinge portion), a container in a contracted state can be formed.
[0045]
The container of the present invention may be formed of a foamed resin sheet (such as a foamed resin sheet having an expansion ratio of about 1.1 to 3 times) or a non-foamed resin sheet. It can be formed of a resin sheet. Examples of the resin sheet include thermoplastic resin sheets, for example, polyolefin resin sheets (such as polypropylene resin sheets), styrene resin sheets, vinyl halide resin sheets (vinyl chloride resin sheets), and polyester resin sheets (polyethylene terephthalate). And polyalkylene arylate resins such as polybutylene terephthalate and polyalkylene arylate copolyester). These resin sheets may be uniaxially or biaxially stretched as necessary. The styrene resin sheet is made of a polystyrene resin, a polystyrene resin and a soft resin (at least one soft resin selected from impact-resistant polystyrene or a rubber-grafted styrene resin, a styrene-diene copolymer, a thermoplastic elastomer, and the like). And a styrene-based resin composition composed of The thickness of the resin sheet is not particularly limited, and may be, for example, about 0.1 to 2 mm, preferably about 0.2 to 1.5 mm, and particularly about 0.3 to 1 mm.
[0046]
The container forming of the sheet can be performed by using a conventional method, for example, a thermoforming method such as vacuum forming, blow molding, pressure forming, and matched molding.
[0047]
The container of the present invention may have a lid that can open and close the opening of the container. In a container provided with a lid, a fitting portion to which the lid can be attached / detached may be formed at the periphery of the opening.
[0048]
The container (or packaging container) of the present invention is compact, has high portability or transportability, and can be restored to a container having a large volume when used. Therefore, the container (or packaging container) can be used in various containers such as cups and cups. Widely available. It can also be used as a portable container.
[0049]
【The invention's effect】
In the present invention, since there are a plurality of peripheral walls formed with a plurality of hinge portions and vertical folds, the container can be reversibly expanded and contracted, and a container having a predetermined shape can be formed by an extension operation. Further, even if it is formed of a non-foamed resin sheet, it can be smoothly expanded or contracted by the expansion and contraction operation, and can be expanded to a height twice or more as high as the contracted state. Furthermore, the elastic container of the present invention can form a compact container in a contracted or compressed state from a sheet, and can be smoothly extended or expanded into a large-volume container form when used, thereby increasing the productivity of the elastic container. Can be.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing an example of an elastic container of the present invention.
FIG. 2 is a partial end view showing the elastic container of FIG. 1;
FIG. 3 is a schematic perspective view showing an extended state of the elastic container of FIG. 1;
FIG. 4 is a partial end view showing the elastic container of FIG. 3;
FIG. 5 is a schematic perspective view showing another example of the elastic container (in a contracted state) of the present invention.
FIG. 6 is a partial end view showing the elastic container of FIG. 5;
[Explanation of symbols]
1. Bottom wall
2 ... side wall
3. First peripheral wall
4: Second peripheral wall
5: Third peripheral wall
6: Fourth peripheral wall
7 First hinge part
8: second hinge portion
10, 11, 12 ... vertical fold
18 ... Circular rib

Claims

A container constituted by a bottom wall and a side wall which is inclined outward as a whole from the bottom wall toward the opening, wherein the side wall has a plurality of vertically extending plurality of hinge portions. A peripheral fold extending along the same line in the vertical direction is formed adjacent to each other on the plurality of peripheral walls, and the peripheral wall on the bottom wall side with respect to the peripheral wall on the opening side; Is an elastic container that can be folded relatively.

The side wall includes an upper peripheral wall on the opening side, a lower peripheral wall on the bottom wall, a plurality of intermediate peripheral walls interposed between the upper peripheral wall and the lower peripheral wall, and at least one intermediate peripheral wall. A hinge portion is formed on both sides of the intermediate peripheral wall, and in a contracted state, a plurality of intermediate peripheral walls and a lower peripheral wall are formed in a polygonal shape having a mountain cross section toward the opening, and the intermediate peripheral wall is extended. The stretchable container according to claim 1, wherein the portion and the upper peripheral wall gradually increase in diameter from the bottom wall toward the opening and are inclined.

A first peripheral wall that inclines inward from the opening toward the bottom wall, and a second peripheral wall that inclines from the first peripheral wall toward the opening through the first hinge portion , A third peripheral wall extending laterally from the second peripheral wall via a second hinge, and a fourth peripheral wall extending from the third peripheral wall to the bottom wall. Vertical folds are formed adjacent to each other on at least the second peripheral wall and the third peripheral wall, the first hinge is formed to have a narrow width, and the second hinge is linearly formed. The elastic container according to claim 1, which is formed.

The stretchable container according to any one of claims 1 to 3, wherein the vertical fold is interrupted at the hinge on the opening side, and the vertical fold is formed continuously at the hinge on the bottom wall.

The elastic container according to claim 1, wherein the second hinge portion is formed as an annular rib.

In the contracted state, when a vertical angle with respect to the bottom wall surface is set as a reference angle, the first peripheral wall portion is inclined outward toward the opening at an angle of 5 to 30 ° from the reference angle, and the second peripheral wall portion is The elasticity according to claim 3, wherein the third peripheral wall portion is inclined inward toward the opening at an angle of 10 to 50 degrees from the reference angle, and the third peripheral wall portion extends laterally at an angle of 70 to 110 degrees from the reference angle. container.

The stretchable container according to claim 1, wherein the stretchable container is formed of a resin sheet, and the width of the vertical fold adjacent in the circumferential direction is increased toward the opening.

A method for producing a stretchable container according to claim 1, wherein the resin sheet is molded.

By forming a resin sheet, a bottom wall is formed, and a side wall having a peripheral wall portion that is inclined outward as a whole from the bottom wall toward the opening is formed. A method of manufacturing a container in which a peripheral wall portion on the side is relatively extensible from a contracted state, wherein a plurality of peripheral wall regions are radially formed through a plurality of hinge portions that can be bent by forming a sheet; 9. A method according to claim 8, wherein longitudinally extending longitudinal folds are formed in the peripheral wall region of the peripheral wall and are adjacent to each other in the circumferential direction to form a container in a contracted state.