JP2004123105A

JP2004123105A - Paper container

Info

Publication number: JP2004123105A
Application number: JP2002285524A
Authority: JP
Inventors: Yoshihiko Uejima; 上島　嘉彦; Kiyomi Toge; 峠　清美; Masafumi Nishinokoshi; 西之腰　雅史; Nariyuki Ishibashi; 石橋　成幸
Original assignee: UEDA INSATSU SHIKO KK
Current assignee: UEDA INSATSU SHIKO KK
Priority date: 2002-09-30
Filing date: 2002-09-30
Publication date: 2004-04-22
Anticipated expiration: 2022-09-30
Also published as: JP4098051B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper container, of which a lid can be fitted into a container body firmly, has no gap between the trunk wall of the container body and an engaging part of the lid, and cannot be altered easily, thus superior in preventing a malignant alteration. <P>SOLUTION: The lid 2 has a circular wall 7 having a lower curled portion 14 curled inward and upward. The lower curled portion 14 comprises a lower arc 17, whose end is in contact with the trunk wall 3 of the container body 1, at the lower end of the curled portion, a trunk wall contacting linear part 18 extending upward from the arc 17 while in contact with the trunk wall 3, and an upper arc 19 extending from the top end of the contacting linear part 18 to come in contact with the lower end of a reinforcing part 5 of the container body 1. The lower curled portion 14 is formed in a post-processing carried out after fitting the lid 2 into the container body 1. An opening tab 20 is formed on the circular wall 7 of the lid 2 in such a way that the tab 20 can be pressed into a space formed between the lower arc 17 and the upper arc 19. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、紙製容器、特に改竄防止蓋付のコップ状の紙製容器に関する。
【０００２】
【従来の技術】
近年、コップ状の紙製容器にスナック食品等の固形、練り又は粉末食品、あるいは粘性内容物等を封入したものが多く流通している。これらのものは、容器本体の開口部にシート状蓋材をヒートシールして密封したものと、所定形状に成形された蓋体を容器口部に容易に離脱しないように嵌合したものがある。前者は、密封性及び流通段階でのいたずらによる蓋の改竄防止性には優れているが、容器本体及び蓋材のヒートシール面となる側にヒートシール性樹脂をラミネート又はコートしなければならず、容器材に制限を受けると共に、開封後のリシール性がない欠点がある。一方、後者は容器材料に制限を受けないが、容器本体との嵌合封止機能が十分でなく、流通段階での改竄防止性に劣っている欠点がある。
【０００３】
後者の形式の蓋体は、容器本体に嵌合した状態で容器本体の開口端部外周に形成されたカール部（補強部）の下面に係合する係合カール部を予め環状壁の下端に形成しておき、容器本体に内容物充填後に、蓋体を容器本体に上部から押圧して、あるいは容器本体を蓋体に押し上げることにより、蓋体および容器本体のカール部が相対的に弾性変形して、蓋体のカール部が容器本体のカール部を乗り越えて蓋体が嵌合し、嵌合後は蓋体を上部に持ち上げても蓋体のカール部上面と容器本体のカール部が係合するので、開封することができない。したがって、開封するには、蓋体のカール部を無理に起したり或いは破断しない限り開封できず、開封があった場合は、外観で容易に判別することができるので、改竄防止及び改竄表示機能を果たすことができる。しかしながら、従来のこの形式の蓋体は、容器本体と蓋体との嵌合のときカール部同士を無理に変形させて乗り越え嵌合させるため、固く嵌合することができず、嵌合にガタが生じ易い欠点がある。また、蓋体のカール部と容器本体の胴部壁にも隙間が生じるので、該隙間から針金等を挿入して蓋体のカールを起して蓋体を開封して、再び元に戻して悪戯しても容易に発見できない場合が生じる恐れがある。
【０００４】
そのため、従来蓋体の環状壁の下半分の内面に接着剤を塗って巻き込み部を形成すると共に巻込部の下方にローレット等で内側から圧接して硬壁を作って巻込部を起すことができないようにしたものが提案されている（例えば、特許文献１参照）。また、蓋体の環状壁の下側に折り曲げ自在な係止壁を連続して設け、容器本体に蓋体を嵌合させた後、後加工により係止壁を環状壁の内側に折り返して、補強部に係合させるようにして容器本体と蓋体をロック状態にするようにしたものも提案されている（特許文献２参照）。
【０００５】
【特許文献１】
実公昭５６−１２２０７号公報（第１頁、第２図）
【特許文献２】
特開２０００−２８９７５９号公報（段落０００５〜０００７、図２）
【０００６】
【発明が解決しようとする課題】
前記提案されている従来技術のうち、前者は環状壁に接着剤を塗って巻き込み部を形成すると共に巻込部の下方にローレット等で内側から圧接して硬壁を作らねばならないので、製造工程が複雑でコスト高になる欠点があると共に、蓋を容器本体に無理に嵌合させるので、ガタが生じ易く堅い嵌合が得にくい問題点がある。また後者の場合は、蓋体を容器本体に嵌合後後加工でカール部を形成させるので、容器本体に堅く嵌合させることができるが、蓋体の係止壁と容器本体の胴部壁との間に隙間ができるので、該隙間から工具等を使って係止壁を起して改竄するのを防止するに未だ満足するものではなかった。さらに、従来のものは、万一蓋体の環状壁内径が容器口径より大き過ぎ、容器本体の補強部と巻締バンド間に隙間ができると、蓋体の巻締が緩くなり改竄防止機能が低下する欠点がある。さらにまた、紙製容器をアイスクリーム等の容器として使用する場合、蓋表面に付着した水滴が巻締カール部内で氷結し、巻締部が単に円弧状のカールであると、長期保存中に次第１２にカールが戻り改竄防止機能が失われるおそれがあった。
【０００７】
そこで、本発明は従来の蓋付き紙製容器の上記問題点を同時に解決しようとするものであり、蓋体を容器本体に堅く嵌合でき、且つ容器本体の胴部壁と蓋体の係合部との隙間がなく、たとえ万一蓋体の巻締バンド内径が容器口径より大き過ぎても、あるいは冷凍内容物の長期保存に使用しても、容易に改竄できない改竄防止に優れた紙製容器を提供することを目的とする。
【０００８】
【課題を解決するための手段】
上記問題点を解決する本発明の紙製容器は、胴部壁と底壁を有し、前記胴部壁の上部開口端部外側に補強部を有する容器本体と、該容器本体に嵌合する環状壁と天壁を有する蓋体の組合せからなる紙製容器であって、前記蓋体の環状壁は内側上向きにカールする下部カール部を有してなり、該下部カール部は、下端にその終端が容器本体の胴部壁に接触する半径Ｒの下側円弧部と、該円弧部から前記容器本体の胴部壁に接触しながら上向きに延びる胴部壁接触直線部と、該胴部壁接触直線部の上端から延び容器本体の補強部の下端と接触するような半径ｒの上側円弧部からなり、前記下部カール部は、前記蓋体を容器本体に嵌合後に後加工で形成してなることを特徴とするものである。
【０００９】
蓋体の環状壁に、周方向にミシン目等の弱化線を形成し、該弱化線の一部が、所定長さだけ環状壁軸方向上向きに屈曲して開口タブを形成して、該開口タブが前記下部カール部の上側円弧部と下側円弧部との間に位置するように配置することによって、該開口タブを前記下側円弧部と上側円弧部間で形成される空間内に押し込むことができるので、カール部に引張タブを設ける必要がなく、全周に同じようにカールを形成することができ、堅く巻き締めるのに有利である。前記周方向の弱化線は、環状壁の上部から該環状壁高さの約１／２〜約４／５の位置に形成するのが望ましい。
【００１０】
前記蓋体は、天壁と環状壁が一体に形成されているもの、環状壁と天壁が別体に形成されているもの何れであってもよい。環状壁と天壁が別体に形成されているものでは、前記環状壁は内側下向きにカールする上部カール部を有し、該上部カール部の下面と容器本体の前記補強部上面とで前記天壁の周縁部を挟持して固定する。また、環状壁と天壁が別体に形成されているものでは、前記環状壁は、帯状ブランクの両端を接着して形成され、該帯状ブランクの接着部となる両端部の上下角部は、互いに斜めに切り欠いて形成され、両端部を接着した状態で、上下端部に上側切欠部、下側切欠部を形成すると、カール部の形成が容易となると共に、接合部での段差も少なくなり良好にカール形成ができるので望ましい。
なお，本発明における「紙製容器」は、基材が紙を主体とする容器をいい、単に天然木材パルプのみからなる紙に限らず、樹脂と紙パルプを混抄した合成紙、あるいは紙層と合成樹脂フィルムや金属箔を積層した積層紙等で製造した容器をいう。
【００１１】
【発明の実施の形態】
以下、本発明を図１及び図２に示す実施形態により詳細に説明する。
図１〜図３は本発明の実施形態に係る紙製容器を示している。
本発明の紙製容器は、コップ状の容器本体１と該容器本体の開口部に外嵌合して開口部を封止する蓋体２とから構成されている。容器本体１は、通常の紙コップと同様に、扇形状の胴部ブランクから形成されたテーパー角θのテーパ円筒状の胴部壁３と、円盤状の底部ブランクの周縁部を下方に屈曲して胴部壁３の下端部に巻締した底壁４とからなり、胴部壁の開口上端は外側にカールさせて補強した補強部５となっている。本実施形態では、補強部５は上下方向に長い楕円状のローングカールとなっている。
【００１２】
一方、蓋体２は、前記コップ本体の補強部５の外径にほぼ等しい直径を有する円盤状の蓋板６と、円筒状の環状壁７の２ピースから構成されている。環状壁７は、帯状ブランクの両端部を接着することにより円筒状に形成したものであるが、帯状ブランクの接着部９となる両端部の上下角部は、互いに斜めに切り欠いて形成され、円筒状に両端部を接着した状態で、図２に示すように上下端部に上側切欠部１１、下側切欠部１２が形成されている。それにより、筒状になった上下両端部を内側に巻いてカール加工する際に、カール加工がし易くなると共に、繋ぎ部のカール厚みの増大を抑え、繋ぎ部によって生じる段差を小さくし、上側カール部では、蓋板との接触面に段差部により生じる隙間を小さく若しくは無くし、下側カール部では容器本体の補強部５の下面との接触面段差部により生じる隙間を小さく若しくは無くすことができるという利点がある。
【００１３】
環状壁７は、蓋板６を容器本体の開口部に強固に保持し、流通段階で悪戯等で開口できないように容器を強固に封鎖し、且つ仮に改竄があった場合は、直ぐにそのことが分かるように表示する改竄防止及び改竄表示機能を果たすものであり、それが確実に果たすことができるように、次のような構造及び寸法関係で形成されている。
蓋体２が容器本体１の補強部に載って容器本体に被さった状態で、蓋体の上側カール部と下側カール部で、容器本体のカール部を挟み付けることで蓋体２は、容器本体１に固定される。したがって、蓋板６を強固に固定するためには、上側カール部１５が蓋板上面に、下側カール部１４が容器本体１の補強部５下面に密接し、且つ容器本体のテーパー状の胴部壁３に密接していることが望ましく、また改竄防止のためには、下側カール部のカールを起すことができないように、下側カール部と胴部壁との間に隙間を無くすこと、また仮にカールを起すことができて開封できたとしても、元の状態に戻すことができないようにすることが望ましい。
【００１４】
そこで、本発明では、上記条件を全て達成する構造として、蓋体２が容器本体１に被さった状態で、次のような巻締構造となっている。即ち、本実施形態では図３に示すように、前記蓋体２の環状壁７は内側上向きにカールする下部カール部１４と内側下向きにカールする上部カール部１５を有し、その間が直線部１６となっている。下部カール部１４は、下端にその終端が容器本体１の胴部壁３に接触する半径Ｒの下側円弧部１７と、該円弧部から前記容器本体１の胴部壁３に接触しながら上向きに延びる胴部壁接触直線部１８と、該胴部壁接触直線部１８の上端から延び容器本体の補強部５の下端及び環状壁の直線部内面と接触するような半径ｒの上側円弧部１９からなっている。そして、前記下部カール部は、後述するように、蓋体２を容器本体１に嵌合後に後加工により形成される。
【００１５】
後加工により巻締するので、前記容器本体１の胴部壁３は、蓋体２の胴部壁接触直線部１８が確実に胴部壁に接触し、且つ上側円弧部１９が確実に容器本体の補強部５の下端と接触し、且つ蓋体の環状壁の直線部内面に密に接触させることができる。その際、上側円弧１９は、その円弧周面が少なくとも補強部５の円弧と接し、且つ望ましくは直線部内面に接していればよく、その先端が完全に丸くなるまでカールする必要はない。また、下部カール部１４の胴部壁接触直線部１８は必ずしも長くなくてもよく、下側円弧部１７と上側円弧部１９が近接して殆ど接するようにしてもよいが、胴部壁接触直線部１８が長い程、該胴部壁接触直線部１８とそれに接触している容器本体の胴部壁３との間に強制的に器具等を挿入して上側円弧部に掛けて下側カール部を起すことが困難となるので、器具等を使って下側カール部を起して改竄するのを確実に防ぐために、また後述するように開口タブを円弧部にかからないように設けるためには、胴部壁接触直線部１８はある程度の長さを有するのが望ましい。
【００１６】
以上のように、蓋体の環状壁の下部カール部１４が下側円弧部１７と上側円弧部１９及びその間を結ぶ直線部１６からなり、図３に示すように、下部カール部高さが寸法Ｆとなっている。そして、該下部カール部高さＦ、上部カール部高さＫ、及び容器本体の補強部高さＧの総和が巻締バンド高さＡとなる。上記寸法のうち、上部カール部高さＫは可能な限り小さくすることが望ましく、蓋体の大きさに関係なくほぼ同一寸法であり、容器本体の補強部高さＧは容器本体の補強部形状によって任意に選択できる。巻締バンド高さＡは、容器の外観設計によって任意に決定される。従って、巻締バンド高さＡが決定されることによって、下部カール部高さＦが決定され、下側円弧部１７が容器本体のテーパー壁３と接するための下側円弧部の半径Ｒ、及び上側円弧部１９がテーパー壁３と補強部５及びストレート部１６と接するための上側円弧部の半径ｒ及び胴部壁接触直線部１８の長さが決定され、環状壁７の高さＢ（図２）が決定される。
【００１７】
以上のように、本発明の紙製容器においては、蓋体の環状壁７の下部カール部１４は、その外周面が下側円弧部１７と上側円弧部１９及びその間を結ぶ直線部１６からなり、内周面は下側円弧部１７と上側円弧部１９及びその間を結ぶ胴部壁接触直線部１８とからなり、図３に示すように、内部がほぼ断面楕円形状を呈し中空となっている。そのため、開口抵抗が増し改竄防止に有効であると共に、次のように下部カール部１４に面する直線部１６に開口タブ２０を上向きに設けることができるという有利さがある。従来のこの種紙容器の場合、環状壁の下方に周方向の弱化線と該周方向の弱化線から下方円弧部に延びる縦方向弱化線を入れて、該縦方向弱化線から所定幅を下方に伸ばして、開口する際の開口タブ（引張タブ）とし、開蓋する際には該開口タブを引張ることにより、巻締バンド部をミシン目に沿って周方向に破断することによって開口できるようにしている。そのため、開口タブが位置する部分は、巻締が緩みその分、強固な巻締ができない欠点があった。
【００１８】
これに対し、本実施形態では、特に図３に明示するように、下部カール部１４が中空になっているので、該中空に面して周方向弱化線２２（図１）から上側に開口タブ２０を設けて、矢印２１方向から開口タブ２０を下部カール部内に押し込むことによって、図３に仮想線で示すように開口タブ２０を区画している弱化線２２を破断させて、押し倒すことが可能になった。そして、押し倒した開口タブ２０を摘んで、外側に引き起こしてそのまま引張れば、周方向弱化線２０に沿って破断させて開封することができる。従って、本実施形態によれば、開口タブをカール部に係らないように設けることができるので、カール部の巻締に開口タブが悪影響を与えることがなく、強固にカール部を形成することができる。前記周方向の弱化線は、環状壁７の上部から該環状壁高さＢの約１／２〜約４／５の位置に形成するのが望ましい。
【００１９】
本実施形態の紙製容器は、以上の構造からなり、容器本体１は通常の紙コップと同様にして製造することができる。蓋体は、図２に示すように、予め弱化線２２及び開口タブ２０が形成されたブランクを接着部９で接着して環状壁７を形成し、その上端部を内側にカール加工して上部カール部１５を形成する。そして、その内部に蓋板６を上部カール部１５下面に接触するまで嵌合する。なお、蓋板６は単に嵌合するだけでもよく、あるいは蓋板６の上面と上部カール部１５下面と接着剤で接着して分離しないように一体に組立てもよい。蓋体は、以上のような状態で出荷され、充填密封ラインで内容物充填後に容器本体に嵌合してから後加工により下部カール部を巻締して形成する。後加工は、蓋体を容器本体に被せて、その上面をチャックで押えた状態で下方にストレートなっている環状壁７を下方より巻締ツールで押し上げてその先端部にカール癖をつけ、さらにツールを相対的に上方に移動させることにより行う。それにより、環状壁は下方部で湾曲しながら容器本体の胴部壁３に摺接して上昇し、その上端部が容器本体の補強部５下端に当たって湾曲変形しながら進み、さらに環状壁内周面に当たって曲げられることにより、上側円弧部１９が形成され、容器本体への蓋体の巻締が完了する。
【００２０】
以上のような後加工方法で巻締を行うため、蓋体の環状壁の下側カールが容器本体のテーパー状の胴部壁３と補強部５下端に密接し、且つ環状壁内周面に密接した状態で巻締することができるので、堅い状態に巻締することができる。
【００２１】
図４と図５は、本発明の他の実施形態に係る紙製容器を示し、この実施形態は、容器本体３０の補強部３１が円形にカールされている場合を示している。その他の構造は、前記実施形態と同様であるので、同様な引出し符号を付し、詳細な説明は省略する。また、図６と図７は本発明のさらに他の実施形態に係る紙製容器を示し、この実施形態は、容器本体３５の補強部３６は、カールしたのをプレスすることによって平坦フランジに形成してある点が相違している。従って、この実施形態の場合は、上側円弧部がフランジ状の補強部３６下面の平坦部に接することになる。
【００２２】
【実施例】
本発明に係る紙製容器の改竄防止機能の有効性を確認するために、図４及び図５に示す形状の蓋体及び容器本体を製造し、その開口強度を測定して比較例として蓋体の環状壁４２が図８に示す従来形状の紙製容器４０と比較した。比較例は下部カール部４３は半カール状となっている。
容器本体及び蓋体の各寸法は次の通りである。
容器本体：
口径　　　　：　　９６．５ｍｍ、
補強部　　　：　　丸カール
テーパー角θ：　　８°
蓋体：
巻締バンド高さＡ：　　１３．５ｍｍ
上部カール部半径：　　　１．２５ｍｍ
下部カール部高さＦ：　　８．０ｍｍ
下側円弧部半径Ｒ：　　　１．９６ｍｍ
上側円弧部半径ｒ：　　　１．４４ｍｍ
【００２３】
開口強度の試験方法
上記紙製容器の開口強度を測定するために、専用の蓋取付用ジグと容器本体取付用ジグを製作し、上下への引張力が容器本体及び蓋体の全周に渡って均等に作用するように工夫して、それを引張試験機に取り付けて測定した。
試験方法は、容器本体に蓋体を巻締して容器を封緘した状態で、蓋体の上部カール部１５と蓋板６との隙間に蓋取付用ジグに６０°間隔で設けられた突起を差込み螺子で閉め付け固定して蓋取付用ジグに蓋体を取り付けた。また、容器本体は、その底部巻締壁に９０°間隔で穴を開け、容器本体取付用ジグに９０°間隔で設けられた螺子で固定して取り付けた。以上のように，容器本体及び蓋にセットされた容器本体取付用ジグと蓋取付用ジグを引張試験機にセットし、容器本体取付用ジグを固定した状態で、蓋取付用ジグ側を試験速度２０ｍｍ／ｍｉｎで垂直方向に引っ張り、容器本体から蓋体が外れるまでの間の最大値を開口強度とした。
【００２４】
その結果、実施例及び比較例の開口強度はそれぞれ表１に示す通りであった。試験数はそれぞれについて５個について行ったところ、５個ともほぼ同様な結果を示したので、それ以上行っても同様な結果が予測され、５個で終了した。
【表１】

【００２５】
表１から明らかなように、本実施形態の紙製容器は、図８に示す従来のものと比較して、開口強度が約１．５倍もあり、改竄防止性に極めて優れていることが確認された。
【００２６】
【発明の効果】
以上のように、本発明によれば、蓋体を容器本体に堅く嵌合でき、且つ容器本体の胴部壁と蓋体の係合部との隙間がなく、たとえ万一蓋体の巻締バンド内径が容器口径より大き過ぎても、あるいは冷凍内容物の長期保存に使用しても、容易に改竄できない改竄防止に優れた紙製容器を得ることができる。その上請求項２記載の発明によれば、開口タブを下部カール部内に押し込んで開口することができるので、カール部に引張タブを設ける必要がなく、全周に同じようにカールを形成することができ、堅く巻締することができる。さらに、請求項５記載の発明によれば、環状壁接合部のカール部形成が容易となる共に、接合部での段差も少なくなり、良好にカール形成ができる。
【図面の簡単な説明】
【図１】本発明の実施形態に係る紙製容器の中心線より右側が正面断面、左側が正面図である。
【図２】蓋体の環状壁ブランクを接着した状態での正面図である。
【図３】図１に示す紙製容器の巻締部断面の拡大図である。
【図４】本発明の他の実施形態に係る紙製容器の中心線より右側が正面断面、左側が正面図である。
【図５】図４に示す紙製容器の巻締部断面の拡大図である。
【図６】本発明のさらに他の実施形態に係る紙製容器の中心線より右側が正面断面、左側が正面図である。
【図７】図６に示す紙製容器の巻締部断面の拡大図である。
【図８】比較例の紙製容器の巻締部断面の拡大図である。
【符号の説明】
１　容器本体　　　　　　　　　　２　蓋体
３　胴部壁　　　　　　　　　　　４　底壁
６　蓋板　　　　　　　　　　　　７　環状壁
９　接着部　　　　　　　　　　　１１　上側切欠き部
１２　下側切欠き部　　　　　　　　１４　下部カール部
１５　上部カール部　　　　　　　　１６　ストレート部
１７　下側円弧部　　　　　　　　　１８　胴部壁接触直線部
１９　上側円弧部　　　　　　　　　２０　開口タブ
２２　周方向弱化線[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a paper container, particularly a cup-shaped paper container with a tamper-proof lid.
[0002]
[Prior art]
2. Description of the Related Art In recent years, many cup-shaped paper containers in which solid, kneaded or powdered foods such as snack foods, or viscous contents are sealed are widely distributed. These include those in which a sheet-like lid material is heat-sealed and sealed in the opening of the container body, and those in which a lid molded into a predetermined shape is fitted to the container mouth so as not to be easily detached. . The former is excellent in sealing property and preventing falsification of the lid due to tampering at the distribution stage, but the heat sealing resin must be laminated or coated on the side of the container body and the lid material that is to be the heat sealing surface. In addition, there is a disadvantage that the material of the container is limited and there is no resealability after opening. On the other hand, the latter is not limited by the material of the container, but has a drawback that the function of fitting and sealing with the container main body is not sufficient, and the tampering prevention at the distribution stage is poor.
[0003]
In the latter type of lid, an engaging curl portion that engages with the lower surface of a curl portion (reinforcement portion) formed on the outer periphery of the opening end portion of the container body in a state fitted to the container body is previously provided at the lower end of the annular wall. After the contents are filled in the container body, the lid body is pressed against the container body from above or the container body is pushed up to the lid body, so that the curl portions of the lid body and the container body are relatively elastically deformed. Then, the curled portion of the lid rides over the curled portion of the container body and the lid is fitted. After the fitting, the upper surface of the curled portion of the lid and the curled portion of the container body are engaged even if the lid is lifted up. Cannot be opened. Therefore, in order to open the lid, the lid cannot be opened unless the curled portion of the lid is forcibly raised or broken, and if the lid is opened, it can be easily identified by the appearance. Can be fulfilled. However, in the conventional lid of this type, when the container body and the lid are fitted together, the curled portions are forcibly deformed to fit over each other. There is a disadvantage that is easily generated. In addition, since a gap is also formed between the curled portion of the lid and the body wall of the container body, a wire or the like is inserted from the gap to cause curling of the lid, open the lid, and then return to the original position. There is a possibility that mischief may not be easily discovered.
[0004]
Therefore, the adhesive is applied to the inner surface of the lower half of the annular wall of the conventional lid to form the entangled portion, and a hard wall is formed below the entangled portion by pressing against the inside with a knurl or the like to raise the entangled portion. There has been proposed a device that is not able to perform the above-described operations (for example, see Patent Document 1). Further, a bendable locking wall is continuously provided below the annular wall of the lid, and after the lid is fitted to the container body, the locking wall is folded back inside the annular wall by post-processing, There has also been proposed one in which the container body and the lid are locked by engaging with the reinforcing portion (see Patent Document 2).
[0005]
[Patent Document 1]
Japanese Utility Model Publication No. 56-12207 (page 1, FIG. 2)
[Patent Document 2]
JP-A-2000-289759 (paragraphs 0005 to 0007, FIG. 2)
[0006]
[Problems to be solved by the invention]
Among the proposed prior arts, the former requires forming an entrained portion by applying an adhesive to the annular wall and pressing the inner side of the encircled portion with a knurl or the like to form a hard wall. However, there is a problem in that the lid is complicated and the cost is high, and since the lid is forcibly fitted to the container main body, there is a problem that play is likely to occur and a firm fitting is difficult to obtain. In the latter case, since the curl portion is formed by post-processing after fitting the lid to the container main body, it can be firmly fitted to the container main body, but the locking wall of the lid and the body wall of the container main body can be fitted. However, it has not been satisfactory yet to prevent the locking wall from being tampered with by using a tool or the like through the gap. Furthermore, in the case of the conventional one, if the inner diameter of the annular wall of the lid is too large than the diameter of the container and a gap is formed between the reinforcing portion of the container body and the tightening band, the tightening of the lid becomes loose and the tampering prevention function is reduced. There is a disadvantage that it decreases. Furthermore, when a paper container is used as a container for ice cream or the like, water droplets adhering to the lid surface freeze in the wound curl portion, and if the wound portion is simply an arc-shaped curl, it gradually increases during long-term storage. There is a risk that the curl will return to No. 12 and the tampering prevention function will be lost.
[0007]
Accordingly, the present invention is to simultaneously solve the above-mentioned problems of the conventional paper container with a lid, in which the lid can be firmly fitted to the container main body, and the engagement between the body wall of the container main body and the lid can be achieved. There is no gap with the part, and even if the inner diameter of the tightening band of the lid is too large than the diameter of the container, or even if it is used for long-term storage of frozen contents, it is easy to tamper with paper It is intended to provide a container.
[0008]
[Means for Solving the Problems]
A paper container of the present invention that solves the above problems has a body wall and a bottom wall, and a container body having a reinforcing portion outside the upper opening end of the body wall, and is fitted to the container body. A paper container comprising a combination of a lid having an annular wall and a top wall, wherein the annular wall of the lid has a lower curl portion curled inward upward, and the lower curl portion has a lower curl at its lower end. A lower arc portion having a radius R whose end contacts the body wall of the container body, a body wall contact straight portion extending upward from the arc portion while contacting the body wall of the container body, and the body wall The lower curl portion is formed by post-processing after the lid is fitted to the container body, the upper arc portion having a radius r extending from the upper end of the contact straight portion and contacting the lower end of the reinforcing portion of the container body. It is characterized by becoming.
[0009]
A weakening line such as a perforation is formed in the annular wall of the lid in the circumferential direction, and a part of the weakening line is bent upward by a predetermined length in the axial direction of the annular wall to form an opening tab. By arranging the tab so as to be located between the upper arc portion and the lower arc portion of the lower curl portion, the opening tab is pressed into the space formed between the lower arc portion and the upper arc portion. Therefore, it is not necessary to provide a tension tab on the curled portion, and the curl can be formed in the same manner on the entire circumference, which is advantageous for tightly tightening. It is preferable that the circumferential weakening line is formed at a position of about 1/2 to about 4/5 of the height of the annular wall from the top of the annular wall.
[0010]
The lid may be one in which the top wall and the annular wall are formed integrally, or one in which the annular wall and the top wall are formed separately. In the case where the annular wall and the top wall are formed separately, the annular wall has an upper curl portion curled inward downward, and the lower surface of the upper curl portion and the upper surface of the reinforcing portion of the container main body form the ceiling. Hold and fix the peripheral edge of the wall. Further, in the case where the annular wall and the top wall are formed separately, the annular wall is formed by bonding both ends of the band-shaped blank, and the upper and lower corners of both ends serving as the bonded portion of the band-shaped blank are: Forming the upper notch and the lower notch at the upper and lower ends in a state where both ends are adhered while being formed by diagonally notching each other facilitates the formation of the curled portion and reduces the step at the joint. This is desirable because curl formation can be performed well.
The “paper container” in the present invention refers to a container whose base material is mainly paper, and is not limited to paper consisting of only natural wood pulp, but also synthetic paper obtained by mixing resin and paper pulp, or paper layer. This refers to a container manufactured from laminated paper in which a synthetic resin film or metal foil is laminated.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the embodiments shown in FIGS.
1 to 3 show a paper container according to an embodiment of the present invention.
The paper container of the present invention comprises a cup-shaped container main body 1 and a lid 2 which is fitted to the opening of the container main body to seal the opening. The container body 1 bends the peripheral edge of the tapered cylindrical body blank 3 having a taper angle θ formed from a fan-shaped body blank and the peripheral edge of the disc-shaped bottom blank in the same manner as a normal paper cup. The bottom wall 4 is wound around the lower end of the body wall 3, and the upper end of the opening of the body wall is a reinforcing portion 5 which is curled outward and reinforced. In this embodiment, the reinforcing portion 5 has an elliptical long curl that is long in the vertical direction.
[0012]
On the other hand, the lid 2 is composed of a disc-shaped lid plate 6 having a diameter substantially equal to the outer diameter of the reinforcing portion 5 of the cup body, and a cylindrical annular wall 7. The annular wall 7 is formed in a cylindrical shape by bonding both ends of the band-shaped blank, and upper and lower corners of both ends serving as the bonding portions 9 of the band-shaped blank are formed by being cut off obliquely with each other. As shown in FIG. 2, an upper cutout 11 and a lower cutout 12 are formed at upper and lower ends in a state where both ends are adhered in a cylindrical shape. As a result, when the upper and lower ends of the tubular shape are curled inward by curling, the curling becomes easier, the increase in the curl thickness of the connecting portion is suppressed, the step generated by the connecting portion is reduced, and In the curl portion, the gap generated by the step portion on the contact surface with the lid plate can be reduced or eliminated, and in the lower curl portion, the gap generated by the contact surface step portion with the lower surface of the reinforcing portion 5 of the container body can be reduced or eliminated. There is an advantage.
[0013]
The annular wall 7 holds the cover plate 6 firmly in the opening of the container body, tightly closes the container so that it cannot be opened by mischief, etc. at the distribution stage, and if there is tampering, immediately It fulfills the function of preventing falsification and displaying falsification so that it can be understood, and is formed with the following structure and dimensional relationship so that it can be reliably performed.
In a state where the cover 2 is placed on the reinforcing portion of the container body 1 and covers the container body, the curl portion of the container body is sandwiched between the upper curl portion and the lower curl portion of the cover, so that the cover 2 It is fixed to the main body 1. Therefore, in order to firmly fix the cover plate 6, the upper curl portion 15 is in close contact with the upper surface of the cover plate, the lower curl portion 14 is in close contact with the lower surface of the reinforcing portion 5 of the container main body 1, and the tapered body of the container main body. It is desirable that the lower curl portion is close to the body wall 3 and, in order to prevent tampering, there is no gap between the lower curl portion and the body wall so that the lower curl portion cannot be curled. Further, even if curling can be caused and the package can be opened, it is desirable that the original state cannot be restored.
[0014]
Therefore, in the present invention, as a structure that achieves all of the above conditions, the following tightening structure with the lid 2 covered on the container body 1 is provided. That is, in the present embodiment, as shown in FIG. 3, the annular wall 7 of the lid 2 has a lower curl portion 14 curling inward upward and an upper curl portion 15 curling inward downward, and a linear portion 16 therebetween. It has become. The lower curl portion 14 has a lower circular arc portion 17 whose lower end has a lower end with a radius R contacting the trunk wall 3 of the container main body 1, and an upward direction from the arc portion while contacting the trunk wall 3 of the container main body 1. A wall portion contacting straight portion 18 extending to the upper portion and an upper arc portion 19 having a radius r extending from the upper end of the body wall contacting linear portion 18 and contacting the lower end of the reinforcing portion 5 of the container body and the inner surface of the straight portion of the annular wall. Consists of The lower curl portion is formed by post-processing after fitting the lid 2 to the container body 1 as described later.
[0015]
Since the body wall 3 of the container body 1 is securely tightened by post-processing, the body wall contact linear portion 18 of the lid 2 reliably contacts the body wall, and the upper circular arc portion 19 reliably secures the container body. Can be in contact with the lower end of the reinforcing portion 5 and closely contact the inner surface of the linear portion of the annular wall of the lid. At this time, the upper circular arc 19 only needs to have at least its circular peripheral surface in contact with the circular arc of the reinforcing portion 5 and preferably in contact with the inner surface of the straight portion, and does not need to be curled until its tip is completely rounded. The trunk wall contact straight portion 18 of the lower curl portion 14 does not necessarily have to be long, and the lower arc portion 17 and the upper arc portion 19 may be close to and almost in contact with each other. As the length of the portion 18 is longer, an instrument or the like is forcibly inserted between the body wall contacting straight portion 18 and the body wall 3 of the container body in contact therewith, and the device is hung on the upper arc portion to lower the lower curl portion. In order to reliably prevent the lower curl portion from being tampered with by using an instrument or the like, and to provide an opening tab so as not to cover the arc portion as described later, It is desirable that the body wall contact straight portion 18 has a certain length.
[0016]
As described above, the lower curl portion 14 of the annular wall of the lid is composed of the lower circular arc portion 17, the upper circular arc portion 19, and the straight line portion 16 connecting between them, and as shown in FIG. It is F. Then, the sum of the lower curl portion height F, the upper curl portion height K, and the height G of the reinforcing portion of the container body is the tightening band height A. Of the above dimensions, it is desirable that the height K of the upper curl portion is as small as possible, and is substantially the same regardless of the size of the lid, and the height G of the reinforcing portion of the container main body is the shape of the reinforcing portion of the container main body. Can be selected arbitrarily. The height A of the tightening band is arbitrarily determined by the external design of the container. Accordingly, by determining the height A of the tightening band, the height F of the lower curl portion is determined, and the radius R of the lower arc portion for the lower arc portion 17 to contact the tapered wall 3 of the container body, and The radius r of the upper arc portion and the length of the trunk wall contact straight portion 18 for the upper arc portion 19 to contact the tapered wall 3 with the reinforcing portion 5 and the straight portion 16 are determined, and the height B of the annular wall 7 (FIG. 2) is determined.
[0017]
As described above, in the paper container of the present invention, the lower curl portion 14 of the annular wall 7 of the lid body has the outer peripheral surface formed of the lower circular arc portion 17, the upper circular arc portion 19, and the linear portion 16 connecting between them. The inner peripheral surface is composed of a lower circular arc portion 17, an upper circular arc portion 19, and a trunk wall contact linear portion 18 connecting the lower circular arc portion 17 and the inside, as shown in FIG. . Therefore, there is an advantage that the opening resistance is increased, which is effective in preventing tampering, and that the opening tab 20 can be provided upward in the linear portion 16 facing the lower curl portion 14 as follows. In the case of this type of conventional paper container, a circumferential weakening line and a vertical weakening line extending from the circumferential weakening line to the lower arc portion are inserted below the annular wall, and a predetermined width is lowered from the vertical weakening line. To form an opening tab (tensile tab) at the time of opening, and at the time of opening the cover, by pulling the opening tab, so that the opening can be opened by breaking the tightening band portion in the circumferential direction along the perforation. I have to. For this reason, the portion where the opening tab is located has a disadvantage in that the tightening is loosened, and accordingly, a strong tightening cannot be performed.
[0018]
On the other hand, in the present embodiment, since the lower curl portion 14 is hollow, as clearly shown in FIG. 3 in particular, the opening tab extends upward from the circumferential weakening line 22 (FIG. 1) facing the hollow. By providing the opening 20 and pushing the opening tab 20 into the lower curl portion from the direction of the arrow 21, the weakening line 22 defining the opening tab 20 can be broken and pushed down as shown by the phantom line in FIG. Became. Then, if the pushed-down opening tab 20 is pinched, raised outward and pulled as it is, it can be broken along the circumferential weakening line 20 and opened. Therefore, according to the present embodiment, since the opening tab can be provided so as not to be involved in the curled portion, the opening tab does not adversely affect the tightening of the curled portion, and the curled portion can be formed firmly. it can. The circumferential weakening line is preferably formed at a position of about 1/2 to about 4/5 of the height B of the annular wall from the upper part of the annular wall 7.
[0019]
The paper container of the present embodiment has the above structure, and the container body 1 can be manufactured in the same manner as a normal paper cup. As shown in FIG. 2, the lid body is formed by bonding a blank in which the weakening line 22 and the opening tab 20 have been formed in advance by the bonding portion 9 to form the annular wall 7, and curling the upper end thereof inward to form the upper portion. A curl portion 15 is formed. Then, the cover plate 6 is fitted therein until it comes into contact with the lower surface of the upper curl portion 15. Note that the cover plate 6 may be simply fitted, or may be assembled integrally with the upper surface of the cover plate 6 and the lower surface of the upper curl portion 15 with an adhesive so as not to be separated. The lid is shipped in such a state as described above, is fitted to the container body after filling the contents in the filling and sealing line, and is formed by winding the lower curl portion by post-processing. In the post-processing, the lid is put on the container body, and the annular wall 7 that is straight downward is pushed up from below by a tightening tool with the upper surface being pressed by a chuck, and a curl is formed on the tip end thereof. This is done by moving the tool relatively upward. Accordingly, the annular wall slides against the body wall 3 of the container body and rises while curving at the lower portion, and its upper end portion advances while bending and deforming against the lower end of the reinforcing portion 5 of the container body. , The upper arc portion 19 is formed, and the fastening of the lid to the container body is completed.
[0020]
Since the winding is performed by the post-processing method as described above, the lower curl of the annular wall of the lid is in close contact with the tapered body wall 3 and the lower end of the reinforcing portion 5 of the container main body, and is formed on the inner peripheral surface of the annular wall. Since it can be tightly wound, it can be tightly wound.
[0021]
FIGS. 4 and 5 show a paper container according to another embodiment of the present invention. This embodiment shows a case where the reinforcing portion 31 of the container body 30 is curled in a circular shape. Other structures are the same as those of the above-described embodiment, and therefore, the same reference numerals are given and the detailed description is omitted. 6 and 7 show a paper container according to still another embodiment of the present invention. In this embodiment, the reinforcing portion 36 of the container body 35 is formed into a flat flange by pressing the curled portion. The difference is that they are. Therefore, in the case of this embodiment, the upper circular portion comes into contact with the flat portion on the lower surface of the flange-like reinforcing portion 36.
[0022]
【Example】
In order to confirm the effectiveness of the falsification prevention function of the paper container according to the present invention, a lid body and a container body having the shapes shown in FIGS. 4 and 5 were manufactured, and the opening strength was measured. The annular wall 42 was compared with the conventional paper container 40 shown in FIG. In the comparative example, the lower curl portion 43 has a semi-curl shape.
The dimensions of the container body and the lid are as follows.
Container body:
Caliber: 96.5mm,
Reinforcing part: Round curl taper angle θ: 8 °
Lid:
Winding band height A: 13.5 mm
Upper curl radius: 1.25 mm
Lower curl height F: 8.0 mm
Lower circular arc radius R: 1.96 mm
Upper circular arc radius r: 1.44 mm
[0023]
Test method for opening strength To measure the opening strength of the paper container, a special jig for mounting the lid and a jig for mounting the main body of the container were manufactured, and the pulling force was applied vertically to the entire circumference of the main body and the lid. It was devised to work evenly, and it was attached to a tensile tester and measured.
The test method is as follows. In a state where the lid is wound around the container body and the container is sealed, protrusions provided at intervals of 60 ° on the lid mounting jig are provided in the gap between the upper curl portion 15 of the lid and the lid plate 6. The cover was attached and fixed to the lid mounting jig by closing and fixing with an insertion screw. Further, the container main body was formed by making holes at 90 ° intervals on the bottom tightened wall thereof and fixing it to the container body mounting jig with screws provided at 90 ° intervals. As described above, the jig for mounting the container body and the jig for mounting the lid set on the container body and the lid are set on the tensile tester. Pulling in the vertical direction at 20 mm / min, the maximum value until the lid came off from the container body was defined as the opening strength.
[0024]
As a result, the opening strengths of the examples and the comparative examples were as shown in Table 1. When the number of tests was 5 for each sample, almost the same results were obtained for all the five tests. Similar results were expected even if the test was performed for more than five tests, and the test was completed with five tests.
[Table 1]

[0025]
As is clear from Table 1, the paper container of the present embodiment has an opening strength about 1.5 times that of the conventional container shown in FIG. confirmed.
[0026]
【The invention's effect】
As described above, according to the present invention, the lid can be firmly fitted to the container main body, and there is no gap between the body wall of the container main body and the engaging portion of the lid. Even if the inner diameter of the band is too large than the diameter of the container, or if it is used for long-term storage of frozen contents, a paper container excellent in prevention of tampering that cannot be easily tampered can be obtained. According to the second aspect of the present invention, since the opening tab can be pushed into the lower curl portion and opened, there is no need to provide a tension tab in the curl portion, and the curl is formed in the same manner all around. And can be tightly wound. Further, according to the fifth aspect of the invention, it is easy to form the curled portion of the annular wall joint portion, and the step at the joined portion is reduced, so that the curl can be favorably formed.
[Brief description of the drawings]
FIG. 1 is a front sectional view on the right side of a center line of a paper container according to an embodiment of the present invention, and a front view on the left side.
FIG. 2 is a front view in a state where an annular wall blank of a lid is bonded.
FIG. 3 is an enlarged view of a cross section of a tightening portion of the paper container shown in FIG.
FIG. 4 is a front sectional view on the right side of the center line of the paper container according to another embodiment of the present invention, and a front view on the left side.
FIG. 5 is an enlarged view of a cross section of a tightening portion of the paper container shown in FIG.
FIG. 6 is a front sectional view on the right side of the center line of the paper container according to still another embodiment of the present invention, and a front view on the left side.
FIG. 7 is an enlarged view of a cross section of a tightening portion of the paper container shown in FIG. 6;
FIG. 8 is an enlarged view of a section of a tightening portion of a paper container of a comparative example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Container main body 2 Lid 3 Body wall 4 Bottom wall 6 Cover plate 7 Annular wall 9 Adhesive part 11 Upper notch part 12 Lower notch part 14 Lower curl part 15 Upper curl part 16 Straight part 17 Lower circular arc part 18 Body wall contact linear portion 19 Upper arc portion 20 Opening tab 22 Circumferential weakening line

Claims

Paper comprising a container body having a body wall and a bottom wall, having a reinforcing portion outside the upper opening end of the body wall, and a lid having an annular wall and a top wall fitted to the container body. Container, wherein the annular wall of the lid has a lower curl portion curled inward upward, and the lower curl portion has a lower end with a radius R at which the end thereof contacts the body wall of the container body. A lower circular arc portion, a trunk wall contact linear portion extending upward from the circular arc portion while contacting the trunk wall of the container body, and a reinforcing portion of the container main body extending from an upper end of the trunk wall contact linear portion. A paper container comprising an upper arc portion having a radius r so as to be in contact with a lower end, wherein the lower curl portion is formed by post-processing after the lid is fitted to the container body.

In the annular wall of the lid, a weakening line is formed in a circumferential direction, and a part of the weakening line is bent upward by a predetermined length in the annular wall axial direction to form an opening tab, and the opening tab is formed. The lower tab is disposed so as to be located between the upper arc portion and the lower arc portion of the lower curl portion, and the opening tab is pushed into a space formed between the lower arc portion and the upper arc portion. The paper container according to claim 1, wherein the paper container is formed.

3. The paper container according to claim 1, wherein the circumferential weakening line is formed at a position of about 1/2 to about 4/5 of the height B of the annular wall from an upper portion of the annular wall.

The lid has an annular wall and a top wall formed separately, and the annular wall has an upper curl that curls inward and downward. The paper container according to any one of claims 1 to 3, wherein the paper container holds and fixes the peripheral portion of the top wall.

The annular wall is formed by bonding both ends of the band-shaped blank, and the upper and lower corners of both ends serving as bonding portions of the band-shaped blank are formed by being cut off diagonally to each other. The paper container according to any one of claims 1 to 4, wherein an upper cutout and a lower cutout are formed at an end.