JP2004035092A

JP2004035092A - Container making paper, paper-made container, and manufacturing method for paper-made container

Info

Publication number: JP2004035092A
Application number: JP2002198312A
Authority: JP
Inventors: Minoru Nagae; 永江　実
Original assignee: Toppan Printing Co Ltd
Current assignee: Toppan Inc
Priority date: 2002-07-08
Filing date: 2002-07-08
Publication date: 2004-02-05
Anticipated expiration: 2022-07-08
Also published as: JP4182696B2

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems in pre-foamed type foamed paper that a paper cup is liable to wrinkle in a paper cup making process, a lot of paper powder is generated during foaming, the surface is not smooth because of foaming to show not good printability, neither good transportation efficiency nor good keeping efficiency is obtained because of its low density and so on and to solve problems in post-foamed type foamed paper that a paper making amount of each lot becomes large, small amount production is difficult in view of a profit, freedom in feeding the foamed paper is limited and so on. <P>SOLUTION: The container making paper is obtained by laminating the post-foaming coat paper 2 on one surface of a container making stencil paper 1 such as coat ball, cup stencil paper, no-coat ivory or the like wherein the foaming coat paper 2 is made by coating or impregnating the low density paper with a foaming agent. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、紙箱等のカートン、紙カップ、トレー容器、紙パック等の容器成形用に使用される容器成形用紙及びそれを用いた紙製容器及び紙製容器の製造方法に関する。
【０００２】
【従来の技術】
従来の紙カップ等の紙製容器成形用紙には、通常は、カップ原紙が使用されるが、紙カップの保温性や手触り感等を考慮した場合は、成形用紙として紙層内部に空気を抱き込んだ発泡タイプの発泡紙が使用される。
【０００３】
この発泡紙は、抄紙工程でパルプ材に発泡剤を混入させて抄紙するとともに、この抄紙工程の段階で加熱発泡又は化学発泡処理されたものであり、既に発泡処理された既発泡タイプ（低密度タイプ）の発泡紙であるため、紙カップ成形工程において、皺になり易く、また発泡時の紙粉が多く発生したり、発泡されているために紙面が平滑でなく、そのため印刷適性が良好でないし、また、発泡紙は低密度であるため良好な輸送効率や保管効率が得られない等の問題がある。
【０００４】
また、従来の発泡紙としては、抄紙工程でパルプ材に発泡剤を混入させて抄紙して、この抄紙工程の段階では発泡剤が発泡しないように乾燥処理し、その後の段階で加熱発泡処理するようにした後発泡タイプ（混抄タイプ）の発泡紙があるが、抄紙工程で発泡剤を混抄して製造するため、製造ロット毎の抄紙量が大きくなり、また発泡紙の抄紙機専用化が必要になって、少量生産が採算的に困難で、発泡紙供給の小回りが効かないなどの問題がある。
【０００５】
【発明が解決しようとする課題】
本発明の課題は、既発泡タイプの発泡紙の上記問題を解決するとともに、後発泡タイプの発泡紙の上記問題を解決することにある。
【０００６】
【課題を解決するための手段】
本発明の請求項１に係る発明は、コートボール、カップ原紙、ノーコートアイボリー等の容器成形用原紙の片面に接着性樹脂層を介して後発泡コート紙がラミネートされていることを特徴とする容器成形用紙である。
【０００７】
本発明の請求項２に係る発明は、上記請求項１に係る容器成形用紙において、前記接着性樹脂層が耐水層であることを特徴とする容器成形用紙である。
【０００８】
本発明の請求項３に係る発明は、上記請求項１又は請求項２に係る容器成形用紙において、前記後発泡コート紙が、低密度用紙に発泡剤をコートした又は含浸させたものであることを特徴とする容器成形用紙である。
【０００９】
本発明の請求項４に係る発明は、上記請求項３に係る容器成形用紙において、前記低密度用紙が、不織布又はコースター原紙であることを特徴とする容器成形用紙である。
【００１０】
本発明の請求項５に係る発明は、上記請求項１乃至４のいずれか１項に係る容器成形用紙を用いて容器状に成形され且つ成形後に加熱発泡処理されていることを特徴とする紙製容器である。
【００１１】
本発明の請求項６に係る発明は、上記請求項１乃至４のいずれか１項に係る容器成形用紙を用いて容器状に成形加工した後、加熱発泡工程にて発泡処理することを特徴とする紙製容器の製造方法である。
【００１２】
【発明の実施の形態】
本発明の容器成形用紙の発明の実施の形態を以下に詳細に説明すれば、図１の側断面図に示すように、コートボール、カップ原紙、ノーコートアイボリー等の容器成形原紙１が使用され、該原紙１の片面に、接着性層又は／及び耐水性層として接着性樹脂層３を介して、後発泡コート紙２がラミネートされているものである。
【００１３】
コートボール、カップ原紙、ノーコートアイボリー等の容器成形用原紙１には好ましくは坪量１００ｇ／ｍ２　〜２００ｇ／ｍ２　、又は１５０ｇ／ｍ２　〜２００ｇ／ｍ２　又はそれ以上のものが使用される。
【００１４】
後発泡コート紙２は、密度が０．８ｇ／ｃｍ３　以下、層間剥離強度が３００ｇｆ／１５ｍｍ幅以下の低密度用紙に発泡剤をコートするか又は含浸させたものである。
【００１５】
本発明の容器成形用紙の後発泡コート紙２は、図２に示すように、パルプ不織布等の天然繊維不織布、レーヨン不織布等の化学繊維不織布、あるいはコースター原紙などの低密度用紙４に、熱膨張性マイクロカプセル６（又は化学反応膨張性マイクロカプセル）と、低密度用紙４の繊維５とマイクロカプセル６とを結び付けるアクリル樹脂などのバインダーを配合した発泡剤をコートし又は含浸させたものである。
【００１６】
本発明の容器成形用紙は、容器成形原紙１側の面を容器外面側に、後発泡コート紙２側の面を容器内面側にして、従来の紙製容器の成形加工に使用する一般的なコートボール、カップ原紙、ノーコートアイボリー等の容器成形用原紙の成形加工と同様の公知の成形加工により、図３（ａ）に示すように紙箱、紙カップ、トレー容器、紙パック容器等の紙製容器を成形加工する。
【００１７】
そして、その後、成形加工された前記紙製容器の後発泡コート紙２を、加熱発泡方式（又は化学反応発泡方式）にて発泡処理することにより、図３（ｂ）に示すように、後発泡コート紙２の紙層内に多数の膨張発泡した発泡部２ａを発生させて、後発泡コート紙２の厚さが増加した断熱、保温性、剛性（コシ）のある紙製容器が得られる。
【００１８】
以下に本発明の容器成形用紙の具体的実施例を説明する。
【００１９】
＜実施例１＞
（後発泡コート紙の作成）
坪量４０ｇ／ｍ２　のレーヨン不織布に、下記加熱発泡剤を、全塗布量４０ｇ／ｍ２　ｗｅｔにて、それを４回に分割して塗布した後、加熱乾燥して、後発泡コート紙を得た。
加熱発泡剤（２５重量％固形分）組成：
カプセル材・・・アクリル樹脂
カプセル内ガス・・・イソブタン
バインダー・・・アクリル樹脂
塗布された発泡剤固形分：（１０×０．２５）×４＝１０ｇ／ｍ２
乾燥温度：１２０℃
塗布・乾燥ラインスピード：４０ｍ／分
（後発泡タイプの容器成形用紙の作成）
下記の積層構成にて、本発明の後発泡タイプの容器成形用紙を作成した。
（容器外面側）［ノーコートアイボリー（坪量１９０ｇ／ｍ２　）／ポリエチレン（厚さ３０μｍ）／後発泡コート紙（坪量４０ｇ／ｍ２　、発泡剤固形分１０ｇ／ｍ２　）／ポリエチレン（厚さ３０μｍ）］（容器内面側）
なお、ノーコートアイボリーと後発泡コート紙とのラミネートは、接着性樹脂層（接着性層又は／及び耐水性層）として熱溶融ポリエチレンをサンドラミネートした。
【００２０】
＜実施例２＞
上記実施例１にて作成した後発泡タイプの容器成形用紙を用いて、公知の紙カップ成形加工により、紙製容器として紙カップを成形加工した。
【００２１】
＜実施例３＞
上記実施例２にて得られた紙カップを、１５０℃にて２分間加熱して、紙カップの後発泡コート紙層を発泡させて、断熱性のある紙カップを得た。
紙カップの厚み：加熱前　０．３５ｍｍ
加熱後　１．２０ｍｍ
【００２２】
上記実施例１、２、３により得られた本発明品（後発泡タイプの容器成形用紙及びそれを用いた紙カップ及び発泡後の紙カップ）と、従来品（混抄後発泡タイプの容器成形用紙とカップ原紙）との比較評価結果を下記表１に示す。
◎・・・良好
×・・・不良
【００２３】
【表１】

【００２４】
【発明の効果】
本発明の容器成形用紙は、断熱性や保温性のある紙製容器の成形加工に使用する後発泡タイプのラミネート発泡紙であり、紙カップなどの紙製容器の成形工程後において発泡させることができるため、紙製容器成形工程においては通常の容器成形用原紙と同様に成形でき、成形加工適性も良好であって発泡による紙粉の発生もなく成形でき、また成形加工における皺の発生を解消できる効果がある。
【００２５】
また、本発明の容器成形用紙は、紙製容器成形工程後の発泡処理までは紙面が平滑であるため、それまでは印刷適性が良好であり、また発泡処理までは発泡紙は、従来の既発泡タイプの用紙とは異なり比較的高密度であるため、容器成形用紙による原料又は半製品の良好な輸送効率や保管効率が得られる効果がある。
【００２６】
また、本発明の容器成形用紙は、後発泡タイプの発泡紙でありながら、ラミネートタイプの発泡紙であるため、抄紙工程でパルプ材に発泡剤を混入する工程は省略でき、したがって製造ロット毎の抄紙量が大きくならず、小ロット生産に対応でき、採算的に見合う少量生産が可能であり、発泡紙の供給小回りが効くという効果があり、断熱性能や手触り感の良好な紙製容器の製造に効果的である。
【図面の簡単な説明】
【図１】本発明の容器成形用紙の側断面図。
【図２】本発明の容器成形用紙における後発泡コート紙の層構造を説明する側断面模式図。
【図３】（ａ）〜（ｂ）は本発明の容器成形用紙を用いて成形された紙製容器の側断面図。
【符号の説明】
１…容器成形用原紙　２…後発泡コート紙　２ａ…発泡中空部
３…接着性樹脂層　４…低密度紙　５…パルプ繊維
６…発泡性マイクロカプセル[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a container forming paper used for forming a container such as a carton such as a paper box, a paper cup, a tray container, and a paper pack, a paper container using the same, and a method for manufacturing a paper container.
[0002]
[Prior art]
Conventionally, cup base paper is used for paper container forming paper such as a conventional paper cup, but in consideration of the heat retaining property and the feeling of touch of the paper cup, air is held inside the paper layer as a forming paper. Foamed foam paper is used.
[0003]
This foamed paper is a paper made by mixing a foaming agent into a pulp material in a paper making process, and is also subjected to a heat foaming or a chemical foaming process in a stage of the paper making process. Since it is foamed paper of type (1), it is easy to wrinkle in the paper cup molding process, a lot of paper powder is generated at the time of foaming, and the paper surface is not smooth due to foaming, so that printability is not good. In addition, since the foamed paper has a low density, there is a problem that good transport efficiency and storage efficiency cannot be obtained.
[0004]
Further, as a conventional foamed paper, in a papermaking process, a foaming agent is mixed into a pulp material to make a paper, and in the stage of the papermaking process, a drying process is performed so that the foaming agent does not foam, and a heating and foaming process is performed in a subsequent stage. After that, there is foaming type (mixed paper type) foamed paper, but since it is manufactured by blending the foaming agent in the paper making process, the amount of paper making for each production lot becomes large, and it is necessary to specialize the foamed paper for the paper machine. Therefore, there is a problem that small-scale production is difficult to be profitable, and supply of foamed paper is not effective.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to solve the above-mentioned problems of the foamed paper of the pre-expanded type and to solve the above-mentioned problems of the foamed paper of the post-expanded type.
[0006]
[Means for Solving the Problems]
The invention according to claim 1 of the present invention is characterized in that a post-foam coated paper is laminated via an adhesive resin layer to one side of a container forming raw paper such as a coated ball, a cup raw paper, and an uncoated ivory. Container forming paper.
[0007]
The invention according to claim 2 of the present invention is the container forming paper according to claim 1, wherein the adhesive resin layer is a water-resistant layer.
[0008]
The invention according to claim 3 of the present invention is the container-formed paper according to

claim

1 or 2, wherein the post-foam coated paper is obtained by coating or impregnating a low-density paper with a foaming agent. Container forming paper characterized by the following.
[0009]
The invention according to claim 4 of the present invention is the container forming paper according to claim 3, wherein the low-density paper is a nonwoven fabric or a coaster base paper.
[0010]
The invention according to claim 5 of the present invention is characterized in that the paper is formed into a container shape using the container forming paper according to any one of claims 1 to 4, and is subjected to a heat foaming treatment after the molding. Container.
[0011]
The invention according to claim 6 of the present invention is characterized in that after forming into a container using the container forming paper according to any one of claims 1 to 4, a foaming treatment is performed in a heating foaming step. This is a method for manufacturing a paper container.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
BEST MODE FOR CARRYING OUT THE INVENTION The container forming paper according to the embodiment of the present invention will be described below in detail. As shown in the side sectional view of FIG. 1, a container forming base paper 1 such as a coated ball, cup base paper, and uncoated ivory is used. The post-foam coated paper 2 is laminated on one side of the base paper 1 via an adhesive resin layer 3 as an adhesive layer and / or a water-resistant layer.
[0013]
As the base paper 1 for forming a container such as a coated ball, a base paper for a cup, and an uncoated ivory, those having a basis weight of 100 g / m2 to 200 g / m2, or 150 g / m2 to 200 g / m2 or more are preferably used.
[0014]
The post-foam coated paper 2 is obtained by coating or impregnating a low-density paper having a density of 0.8 g / cm 3 or less and a delamination strength of 300 gf / 15 mm width or less with a foaming agent.
[0015]
As shown in FIG. 2, the post-foam coated paper 2 of the container-formed paper of the present invention is thermally expanded on natural fiber non-woven fabric such as pulp non-woven fabric, chemical fiber non-woven fabric such as rayon non-woven fabric, or low-density paper 4 such as coaster base paper. The microcapsules 6 are coated or impregnated with a foaming agent containing a binder such as an acrylic resin that binds the conductive microcapsules 6 (or the chemically reactive expandable microcapsules) with the fibers 5 of the low-density paper 4 and the microcapsules 6.
[0016]
The container forming paper of the present invention is a general paper used for forming conventional paper containers, with the surface on the side of the container forming base paper 1 facing the outer surface of the container and the surface on the side of the foam-coated paper 2 facing the inner surface of the container. As shown in FIG. 3 (a), a paper box, a paper cup, a tray container, a paper pack container or the like is formed by a known forming process similar to the forming process of the container forming base paper such as a coated ball, a cup base paper, and a non-coated ivory. Form the container.
[0017]
Then, the post-foamed coated paper 2 formed from the paper container is subjected to a foaming treatment by a heating foaming method (or a chemical reaction foaming method), as shown in FIG. By generating a large number of expanded foamed portions 2a in the paper layer of the coated paper 2, a paper container with increased heat insulation, heat retention, and rigidity (stiffness) in which the thickness of the post-foam coated paper 2 is increased can be obtained.
[0018]
Hereinafter, specific examples of the container forming paper of the present invention will be described.
[0019]
<Example 1>
(Create post-foam coated paper)
The following heating foaming agent was applied to a rayon nonwoven fabric having a basis weight of 40 g / m2 in a total application amount of 40 g / m2 wet in four divided applications, and then heated and dried to obtain a post-foamed coated paper. .
Heating foaming agent (25% by weight solids) composition:
Capsule material: acrylic resin capsule gas: isobutane binder: acrylic resin applied foaming agent solid content: (10 × 0.25) × 4 = 10 g / m 2
Drying temperature: 120 ° C
Coating / drying line speed: 40 m / min (preparation of post-foaming type container forming paper)
A post-foaming type container forming paper of the present invention was prepared with the following laminated structure.
(Container outer surface side) [No coat ivory (basis weight 190 g / m2) / polyethylene (thickness 30 μm) / post-foam coated paper (basis weight 40 g / m2, foaming agent solid content 10 g / m2) / polyethylene (thickness 30 μm) ] (Inside of container)
The lamination of the uncoated ivory and the post-foam coated paper was performed by sand-laminating hot-melt polyethylene as an adhesive resin layer (adhesive layer and / or water-resistant layer).
[0020]
<Example 2>
A paper cup was formed as a paper container by the known paper cup molding process using the foaming type container molding paper prepared in Example 1 above.
[0021]
<Example 3>
The paper cup obtained in Example 2 was heated at 150 ° C. for 2 minutes to expand the foam-coated paper layer after the paper cup, thereby obtaining a heat-insulating paper cup.
Paper cup thickness: 0.35mm before heating
After heating 1.20mm
[0022]
The product of the present invention (post-foaming type container-formed paper and paper cup and foamed paper cup using the same) obtained by the above Examples 1, 2 and 3, and a conventional product (mixed and expanded foam-type container-formed paper and cup) Table 1 below shows the results of the comparative evaluation with the base paper).
◎ ・・・ Good × ・・・ Poor [0023]
[Table 1]

[0024]
【The invention's effect】
The container forming paper of the present invention is a laminated foamed paper of a post-foaming type used for forming a heat-insulating or heat-retaining paper container, and can be foamed after a paper container forming process such as a paper cup. Therefore, in the paper container forming step, it can be formed in the same manner as a normal container forming base paper, has good forming processability, can be formed without generating paper powder due to foaming, and can eliminate the occurrence of wrinkles in the forming process. effective.
[0025]
Further, since the container-formed paper of the present invention has a smooth paper surface until the foaming treatment after the paper-made container molding process, the printability is good up to that time. Unlike foam-type paper, it has a relatively high density, so that there is an effect that good transport efficiency and storage efficiency of raw materials or semi-finished products by container-formed paper can be obtained.
[0026]
Further, since the container forming paper of the present invention is a laminated foamed paper while being a post-foamed foamed paper, the step of mixing the foaming agent into the pulp material in the papermaking process can be omitted, and therefore, for each production lot. Manufacture of paper containers with good heat insulation performance and good touch with the effect that the amount of paper making does not increase, it can cope with small lot production, it can produce profitable small quantities, and the supply of foamed paper is effective. It is effective for
[Brief description of the drawings]
FIG. 1 is a side sectional view of a container forming paper of the present invention.
FIG. 2 is a schematic side sectional view illustrating a layer structure of a post-foam coated paper in the container-formed paper of the present invention.
FIGS. 3A and 3B are side sectional views of a paper container formed by using the container forming paper of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Base paper for container molding 2: Post-foam coated paper 2a ... Foam hollow part 3 ... Adhesive resin layer 4 ... Low density paper 5 ... Pulp fiber 6 ... Foamable microcapsule

Claims

Container molded paper characterized in that post-foam coated paper is laminated on one side of a container molded base paper such as a coated ball, cup base paper, and uncoated ivory via an adhesive resin layer.

The container forming paper according to claim 1, wherein the adhesive resin layer is a water-resistant layer.

3. The container-formed paper according to claim 1, wherein the post-foam coated paper is obtained by coating or impregnating a low-density paper with a foaming agent.

The container-formed paper according to claim 3, wherein the low-density paper is a nonwoven fabric or a coaster base paper.

A paper container, which is formed into a container using the container forming paper according to any one of claims 1 to 4, and is subjected to a heat foaming treatment after the formation.

A method for producing a paper container, comprising forming a container using the container forming paper according to any one of claims 1 to 4, and performing a foaming process in a heating foaming step.