JP3781645B2 - Antifogging rubber-modified styrene resin sheet and molded product thereof - Google Patents
Antifogging rubber-modified styrene resin sheet and molded product thereof Download PDFInfo
- Publication number
- JP3781645B2 JP3781645B2 JP2001221250A JP2001221250A JP3781645B2 JP 3781645 B2 JP3781645 B2 JP 3781645B2 JP 2001221250 A JP2001221250 A JP 2001221250A JP 2001221250 A JP2001221250 A JP 2001221250A JP 3781645 B2 JP3781645 B2 JP 3781645B2
- Authority
- JP
- Japan
- Prior art keywords
- rubber
- mass
- resin sheet
- antifogging
- styrene resin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Manufacture Of Macromolecular Shaped Articles (AREA)
- Laminated Bodies (AREA)
- Containers Having Bodies Formed In One Piece (AREA)
- Wrappers (AREA)
- Coating Of Shaped Articles Made Of Macromolecular Substances (AREA)
Description
【０００１】
【発明の属する技術分野】
本発明は、シートのブロッキング防止、強靱性、防曇効果に優れた防曇性ゴム変性スチレン系樹脂シート及びその成形品に関する。更に詳しくは包装材分野等に広く用いられているスチレン系樹脂シートに対し、シートのブロッキング防止、強靱性、防曇効果に優れた特性を付与したスチレン系樹脂シート及びその成形品に関するものである。
【０００２】
【従来の技術】
スチレン系樹脂シートやその成形品は包装、被覆材として広く使用されているが、その表面が疎水性の為に気温や湿度の変化により凝集した水分が微小水滴となり表面に付着する、いわゆる曇りが発生することがある。その曇りにより収納物の見分けが困難となり、商品価値を低下させたり、水滴が成長し内容物に落下した場合、品質の不良化、腐敗の原因となる場合が多かった。また、スチレン系樹脂シートを成形品にする工程で、成形品を重ねてトリミングする際、成形品が割れ、生産性を低下させる原因となる場合も多かった。
【０００３】
この問題を解決しようと、特開平５−２８７０９７号公報ではショ糖脂肪酸エステルとシリコーンエマルジョンと多糖類及び／又は親水性高分子とを含む表面処理剤で、特開平１０−３０９７８５号公報ではショ糖脂肪酸エステルとメチルセルロースの混合物を用いることが記載されているがシートのブロッキング防止、強靱性、防曇効果に優れたとは言えなかった。
【０００４】
【発明が解決しようとする課題】
本発明は、上記のような技術状況の基で、シートのブロッキング防止、強靱性、防曇効果に優れたスチレン系樹脂シート及びその成形品を提供することを目的とする。
【０００５】
【課題を解決するための手段】
本発明者らは、上記の課題を解決すべく鋭意検討を重ねた結果、特定の構成からなる防曇剤を使用することによって本発明に達したものである。すなわち、本発明は、ゴム変性スチレン系樹脂シートをショ糖脂肪酸エステル７６〜９９．９質量％と未反応ビニルピロリドンの量が１０００ｐｐｍ以下であるポリビニルピロリドン系（共）重合体０．１〜２４質量％を含有してなる防曇剤で表面処理して得た防曇性ゴム変性スチレン系樹脂シート及びそのシートを用いて得た成形品とすることによって課題を解決したものである。
【０００６】
以下に本発明を詳しく説明する。
本発明の防曇剤はショ糖脂肪酸エステルと未反応ビニルピロリドンが１０００ｐｐｍ以下であるポリビニルピロリドン系（共）重合体を必須とする。ショ糖脂肪酸エステルは、ショ糖と脂肪酸とのエステルである。ショ糖脂肪酸エステルを構成する脂肪酸としては、例えば、カプロン酸、カプリル酸、ラウリン酸、ミスチリン酸、パルミチン酸、ステアリン酸、ベヘニン酸、モンタン酸等の炭素数６〜３０程度の飽和脂肪酸、リンデン酸、パルミトオレイン酸、オレイン酸、エライジン酸、イソオレイン酸、エルカ酸、リノール酸、リノレン酸等の炭素数１０〜２４程度の不飽和脂肪酸が挙げられ、これら脂肪酸は単独でも併用してもよい。その中でもショ糖脂肪酸エステルを構成する脂肪酸がラウリン酸であり、ラウリン酸成分としての割合が５０質量％以上、更に好ましくは５５質量％以上、特に好ましくは６５質量％以上であるものが好ましい。ラウリン酸成分としての割合が５０質量％以上の場合、表面処理性に優れ、更に防曇効果にも優れる傾向が見られる。なお、ショ糖脂肪酸エステルを構成する脂肪酸とは、ショ糖と脂肪酸からショ糖脂肪酸エステルを成すが、そのエステルを成す前の脂肪酸をここではいう。また、これらショ糖脂肪酸エステルは少なくとも単独でも一種類以上併用使用することもできる。
【０００７】
本発明のポリビニルピロリドン系（共）重合体はビニルピロリドン系単量体の重合体、並びにビニルピロリドン系単量体とビニルピロリドン系単量体に共重合可能な単量体との共重合体である。
【０００８】
本発明で使用されるビニルピロリドン系単量体としてはビニルピロリドン及びその誘導体であって、好ましくはビニルピロリドンである。これらビニルピロリドン系単量体は少なくとも一種以上併用して使用出来る。
【０００９】
本発明で使用されるビニルピロリドン系単量体と共重合可能な単量体としては酢酸ビニル、ビニルイミダゾ−ル、ビニルカプロラクタム等が挙げられる。ビニルピロリドン系単量体及びビニルピロリドン系単量体と共重合可能な単量体との割合は特に制限されることはないが、好ましくはビニルピロリドン系単量体が３０質量％以上、更に好ましくは４０質量％以上、特に好ましくは６０質量％以上である。ビニルピロリドン系単量体が３０質量％以上の場合、防曇効果に優れる傾向が見られる。
【００１０】
本発明のポリビニルピロリドン系（共）重合体中に存在する未反応ビニルピロリドンの量は１０００ｐｐｍ以下である。好ましくは５００ｐｐｍ以下、更に好ましくは３００ｐｐｍ以下、特に好ましくは１００ｐｐｍ以下である。未反応ビニルピロリドンが１０００ｐｐｍより多いとシート成形時に金型が汚染され易く、成形品の透明性を低下させる。また、ショ糖脂肪酸エステルとポリビニルピロリドン系（共）重合体からなる本発明の防曇剤組成中の未反応ビニルピロリドンは好ましくは２００ｐｐｍ以下、更に好ましくは１００ｐｐｍ以下である。
【００１１】
本発明の防曇剤中のショ糖脂肪酸エステルとポリビニルピロリドン系（共）重合体の割合は、ショ糖脂肪酸エステルが７６〜９９．９質量％とポリビニルピロリドン系（共）重合体０．１〜２４質量％である。好ましくはショ糖脂肪酸エステルが８０〜９９．５質量％でポリビニルピロリドン系（共）重合体０．５〜２０質量％、更に好ましくはショ糖脂肪酸エステルが８５〜９８質量％でポリビニルピロリドン系（共）重合体２〜１５質量％、特に好ましくはショ糖脂肪酸エステルが９０〜９７質量％でポリビニルピロリドン系（共）重合体３〜１０質量％である。ショ糖脂肪酸エステルが７６質量％より少ないと防曇効果に劣る。また、ポリビニルピロリドン系（共）重合体が０．１質量％より少ないと防曇効果の持続性に劣り、２４質量％より多いとシートのブロッキング防止に劣る。
【００１２】
ゴム変性スチレン系樹脂シートの表面を防曇剤で処理する際には、ショ糖脂肪酸エステルとポリビニルピロリドン系（共）重合体を溶媒に溶解した溶液として用いる。溶媒としては水、アルコール等が用いられるが特にこれらに限定されるものではない。取扱い上は水が好ましい。その場合、ショ糖脂肪酸エステルとポリビニルピロリドン系（共）重合体の溶液濃度は特に限定されることはないが０．０１〜１０質量％が好ましい。
【００１３】
本発明の防曇性ゴム変性スチレン系樹脂シートに用いるゴム変性スチレン系樹脂シートとは、ゴム変性スチレン系樹脂を成形加工して得た防曇剤で処理する前のシートである。ゴム変性スチレン系樹脂には、ブタジエン系ゴム存在下でスチレン系単量体及び／又はスチレン系単量体と共重合可能な単量体を共重合して得た共重合体及びそれらの混合物が挙げられる。
【００１４】
上記の共重合体に用いられるスチレン系単量体にはスチレン、α−メチルスチレン、ｐ−メチルスチレン、ビニルトルエン、ｔ−ブチルスチレン等が挙げられ、また、スチレン系単量体と共重合可能な単量体としてはアクリル酸、アクリル酸エチル、アクリル酸メチル、アクリル酸ブチル、アクリル酸２−エチルヘキシル、アクリロニトリル、メタクリル酸、メタクリル酸エチル、メタクリル酸メチル、メタクリル酸ブチル、メタクリル酸２−エチルヘキシル、１，３−ブタジエン、２−メチル−１，３−ブタジエン（イソプレン）等が挙げられる。
更にブタジエン系ゴムにはハイシスポリブタジエン、ローシスポリブタジエン、スチレン−ブタジエンゴム、スチレン−ブタジエンブロックゴム、スチレン−ブタジエン−スチレンブロックゴム、部分水添ポリブタジエンゴム等が挙げられる。なお、重合に用いる単量体やブタジエン系ゴムは少なくとも１種類以上を用いることができる。これらゴム変性スチレン系樹脂としてはハイシスポリブタジエン、ローシスポリブタジエン、スチレン−ブタジエン−スチレンブロックゴムの少なくとも１種類以上の存在下でスチレンを重合して得られる耐衝撃性ポリスチレン（ＨＩＰＳ）が好ましい。
【００１５】
ゴム変性スチレン系樹脂、ゴム変性スチレン系樹脂シート中のゴム含有量、ゴム粒子径は特に限定されることはないが、透明性を損なわない範囲であればより好ましい。透明性を重視する場合には、ゴム含有量として好ましくは０．０１〜１０質量％であり、更に好ましくは０．１〜５質量％である。ゴム含有量が０．０１質量％より少ないと、強靱性に劣る傾向にあり、１０質量％より大きいと、透明性に劣る傾向にある。また、ゴム粒子径として好ましくは０．０１μｍ〜１０μｍであり、更に好ましくは０．１μｍ〜５μｍである。ゴム粒子径が０．０１μｍより小さいと強靱性に劣る傾向にあり、１０μｍより大きいと透明性に劣る傾向にある。
【００１６】
ゴム変性スチレン系樹脂をシートに加工する方法は特に限定されることはなく、１軸延伸法、２軸延伸法、多軸延伸法、共押出法、積層法等の常法が挙げられる。また、シートを防曇処理するにはシートの表面をコロナ放電処理法、オゾン処理法、プラズマ処理法等で改質したものが好ましい。
【００１７】
防曇剤処理液をゴム変性スチレン系樹脂シートに処理する方法は特に限定されることはなく、簡便にはロールコーター、ナイフコーター、グラビアロールコーター等を用い塗布する方法が挙げられる。また、噴霧、浸漬等を採用することも出来る。
【００１８】
防曇剤処理した本発明のゴム変性スチレン系樹脂シート表面の防曇剤の固形分は好ましくは０．００５〜０．５ｇ／ｍ2 、更に好ましくは０．０１〜０．４５ｇ／ｍ2 、特に好ましくは０．０１〜０．４ｇ／ｍ2 である。ゴム変性スチレン系樹脂シートの防曇剤の固形分が０．００５ｇ／ｍ2 より少ないと防曇効果に劣る傾向が見られ、また、０．５ｇ／ｍ2 より多いとシート表面の塗工ムラが目立ち始める。
【００１９】
本発明の防曇性ゴム変性スチレン系樹脂シートは、食料品の包装材或いは被覆材としてそのまま使用される。該防曇性ゴム変性スチレン系樹脂シートの厚みは特に限定されることはなく、一般に１００μｍ〜１０ｍｍである。このシートは成形して容器にも用いられる。また、該防曇性ゴム変性スチレン系樹脂シートの透明性を重要視する場合には、該防曇性ゴム変性スチレンの透明性として好ましくはＨａｚｅ（ヘーズ）が１０％以下である。
【００２０】
本発明の成形品とは防曇性ゴム変性スチレン系樹脂シートを圧空成形、真空成形、真空圧空成形等を用いて成形された食料品を包装する蓋容器やフードパックである。
【００２１】
【実施例】
以下に実施例により本発明を説明するが、本発明はこれら実施例によって制限されるものではない。
なお、実施例における物性測定は以下の通り実施した。
（１）ゴム分：ゴム変性スチレン系樹脂シートを試料として日本電子社製９０ＭＨｚ Ｈ１−ＮＭＲを用いて測定した。
（２）ゴム粒子径：ギヤオーブン中で、温度１３０℃、１時間で加熱収縮させたゴム変性スチレン系樹脂シートを日本電子社製透過型電子顕微鏡で撮影した写真を用いて測定した。なお、ゴム粒子径は数１式で計算した平均体積径（[Ｄ]）で表す。
【数１】
（３）未反応ビニルピロリドン量：試料として個体のポリビニピロリドン系（共）重合体１０ｇを１００ｍｌの純水に溶解し、２ｇの酢酸ナトリウムと５０ｍｌのメタノールを加える。この溶液に０．１Ｎのヨウ素液をヨウ素の色が無くなるまで滴定し、更に１０ｍｌ加え、反応が完全に終了するまで約３０分放置する（ヨウ素のトータル量をＡｍｌとする）。その後、０．１Ｎのチオ硫酸ナトリウムで滴定する（チオ硫酸ナトリウム消費量をＢｍｌとする）。なお、指示薬としてデンプン試液を使用する。次式より未反応ビニルピロリドン量を求める。
ビニルピロリドン量（％）＝｛（Ａ−Ｂ）×０．５５５／（試料量（ｇ）｝
【００２２】
（４）シートの透明性：縦方向に２．５倍、横方向に２．５倍延伸した０．２５ｍｍ厚みの２軸延伸ゴム変性スチレン系樹脂シートに、防曇剤を塗布した防曇性ゴム変性スチレン系樹脂シートのＨａｚｅを日本電色工業社製測定機ＮＤＨ−１００１ＤＰにて測定した。
◎：Ｈａｚｅが１０％未満
○：Ｈａｚｅが１０％以上２０％未満
△：Ｈａｚｅが２０％以上
【００２３】
（５）金型汚染性：（４）で得た防曇性ゴム変性スチレン系樹脂シートを関西自動成型機（株）製の真空圧空成型機ＰＫ４００を用い、成型温度１３０℃で天面が平らな蓋容器（２００ｍｍ長×１２０ｍｍ幅×５０ｍｍ高）を２００ショット成型した。２００ショット成型した後、金型の汚染性を目視にて評価した。
○：金型汚染が殆ど見られない。
△：金型汚染が半分程度見られる。
×：金型汚染が大部分で見られる。
【００２４】
（６）シートブロッキング性：（４）で得た防曇剤を塗布した防曇性ゴム変性スチレン系樹脂シートと何も塗布して無いゴム変性スチレン系樹脂シートをそれぞれ１０ｃｍ×１０ｃｍの面積で重ね合わせ、１０ＭＰａの加重下で２４時間放置した後、ゴム変性スチレン系樹脂シートを引き剥がした。全１０組の組み合わせからその時のシート状態を目視にて評価した。
◎：シートに白化無し
○：シート面積の１０％未満に白化が有る
△：シート面積の１０〜４０％に白化が有る
×：シート面積の４０％を超えて白化が有る
【００２５】
（７）防曇効果▲１▼：温度４５℃のお湯を張ったＰＳＰ（ポリスチレンペーパー）容器の上に（５）で得られた蓋容器をそれぞれ１個を張り付けた後、更に温度５℃の冷蔵庫に３０分放置した。その後蓋容器の曇りを目視で評価した。なお、２１から３０ショット目の１０個の容器を用いて評価した。
◎：曇りが殆ど見られない。
○：曇りが一部で見られる。
△：曇りが半分程度見られる。
×：曇りが大部分で見られる。
（８）防曇効果▲２▼：防曇効果▲１▼を評価後、蓋容器を３０ｃｍ／ｓｅｃの速度で上下に１０ｃｍ（元の位置とその位置から１０ｃｍ上）、２０回往復移動させた時、落下した水滴の数をカウントした。水滴のカウント数が少ない方が防曇性に優れていることを示す。
【００２６】
（９）強靱性評価：（５）で得られた耳の付いている蓋容器を２０個重ね、２０個一度に耳の部分をトリミングする作業を合計５回、蓋容器１００個分行った時、蓋容器に割れが発生した個数をカウントした。割れの発生したカウント数が少ない程、強靱性に優れていることを示す。
【００２７】
実施例１
ゴム変性スチレン系樹脂シートとして、ゴム分２．５質量％、ゴム粒子径０．２μｍ、シート厚み０．２５ｍｍの２軸延伸耐衝撃性ポリスチレンシートを用いた。また、防曇剤としてはショ糖脂肪酸エステルを構成する脂肪酸の７０質量％がラウリン酸であるショ糖ラウリン酸エステルで、かつその３８質量％水溶液を用い、ポリビニルピロリドン系（共）重合体には未反応ビニルピロリドンが６０ｐｐｍであるポリビニルピロリドンを用いて、ショ糖ラウリン酸エステルとポリビニルピロリドンを固形分割合で９６質量％と４質量％になるように調整して得た。更にこの防曇剤を１．５質量％水溶液に希釈して、シート表面の防曇剤の固形分が０．０６ｇ／ｍ2 に塗布したシートを得た。また、そのシートを用い、蓋容器（２００ｍｍ長×１２０ｍｍ幅×５０ｍｍ高さ）を成形した。なお、ショ糖ラウリン酸エステルの３８質量％水溶液に第一工業製薬社製ＤＫエステルＳ−Ｌ１８Ａ、ポリビニルピロリドンにＢＡＳＦジャパン社製ルビスコールＫ１７を用いた。表１にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。
【００２８】
実施例２
防曇剤としてはショ糖脂肪酸エステルに実施例１で用いたショ糖ラウリン酸エステルの３８質量％水溶液と、構成する脂肪酸の９５質量％がミリスチン酸であるショ糖ミリスチン酸エステルのペレットを用い、またポリビニルピロリドン系（共）重合体には実施例１で用いたポリビニルピロリドンを用いた。ショ糖ラウリン酸エステルとショ糖ミリスチン酸エステルとポリビニルピロリドンの固形分割合をそれぞれ８６質量％と６質量％と８質量％になるように調整して得た。この防曇剤を用いた以外は実施例１と同様に行った。なお、ショ糖ミリスチン酸エステルに第一工業製薬社製Ｍ−１６０を用いた。表１にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。
【００２９】
実施例３
防曇剤としてはショ糖脂肪酸エステルに実施例１で用いたショ糖ラウリン酸エステルの３８％質量水溶液を用い、ポリビニルピロリドン系（共）重合体に未反応ビニルピロリドンが４０ｐｐｍでビニルピロリドンと酢酸ビニルの割合が７０質量％と３０質量％であるポリビニルピロリドン−酢酸ビニル共重合体を用いた。ショ糖ラウリン酸エステルとポリビニルピロリドン−酢酸ビニル共重合体の固形分割合をそれぞれ８８質量％と１２質量％になるように調整して得た。更にこの防曇剤を０．２５質量％水溶液に希釈して、シート表面の防曇剤の固形分が０．０１ｇ／ｍ2 に塗布したシートを得た。このシートを用いた以外は実施例１と同様に行った。なお、ポリビニルピロリドン−酢酸ビニル共重合体にＢＡＳＦジャパン社製ルビスコールＶＡ６４Ｐを用いた。表１にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。
【００３０】
実施例４
防曇剤としてはショ糖脂肪酸エステルに実施例１で用いたショ糖ラウリン酸エステルの３８質量％水溶液と構成する脂肪酸の７０質量％がステアリン酸であるショ糖ステアリン酸エステルを用い、またポリビニルピロリドン系（共）重合体に実施例１で用いたポリビニルピロリドンと実施例３で用いたポリビニルピロリドン−酢酸ビニル共重合体を用いた。ショ糖ラウリン酸エステルとショ糖ステアリン酸エステルとポリビニルピロリドンとポリビニルピロリドン−酢酸ビニル共重合体の固形分割合をそれぞれ６５質量％と１５質量％と１０質量％と１０質量％になるように調整して得た。この防曇剤を用いた以外は実施例１と同様に行った。なお、防曇剤を成す各成分物質は前記記載の物を用いた。表１にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。
【００３１】
実施例５
ゴム変性スチレン系樹脂シートとして、ゴム分６．０質量％、ゴム粒子径１．０μｍ、シート厚み０．２５ｍｍの２軸延伸メタクリル酸メチル−ブタジエン−スチレン共重合体シートを用いた以外は実施例１と同様に行った。表１にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。
【００３２】
実施例６
ゴム変性スチレン系樹脂シートとして、ゴム分０．５質量％、ゴム粒子径０．０８μｍ、シート厚み０．４ｍｍの２軸延伸耐衝撃性ポリスチレンシートを用いた以外は実施例１と同様に行った。表１にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。
【００３３】
比較例１
防曇剤としては実施例１で用いたショ糖ラウリン酸エステルの３８質量％水溶液を用い、ポリビニルピロリドン系（共）重合体に実施例１で用いたポリビニルピロリドンを用い、ショ糖ラウリン酸エステルとポリビニルピロリドンの固形分割合をそれぞれ５質量％と９５質量％となるように調整して得た。この防曇剤を用いた以外は実施例１と同様行った。表２にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。ブロッキング防止、防曇効果に劣ることが分かる。
【００３４】
比較例２
ゴム変性スチレン系樹脂シートとして、ゴム分１５質量％、ゴム粒子径１．５μｍ、シート厚み０．２５ｍｍの２軸延伸耐衝撃性ポリスチレンシートを用いた。また、防曇剤としては実施例１で用いたショ糖ラウリン酸エステルの３８質量％水溶液を用い、ポリビニルピロリドン系（共）重合体に未反応ビニルピロリドンが２０００ｐｐｍ、重量平均分子量が１２０万であるポリビニルピロリドンを用い、ショ糖ラウリン酸エステルとポリビニルピロリドンの固形分割合をそれぞれ６７質量％と３３質量％となるように調整して得た。更にこの防曇剤を３質量％水溶液に希釈して、シート表面の防曇剤の固形分が０．０３ｇ／ｍ2 に塗布したシートを得た。このシートを用いた以外は実施例１と同様行った。表２にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。金型汚染性、ブロッキング防止、防曇効果に劣ることが分かる。
【００３５】
比較例３
防曇剤としては実施例１で用いたショ糖ラウリン酸エステルの３８質量％水溶液を用い、ポリビニルピロリドン系（共）重合体に未反応ビニルピロリドンが１２００ｐｐｍであるポリビニルピロリドンを用い、ショ糖ラウリン酸エステルとポリビニルピロリドンの固形分割合をそれぞれ７８質量％と２２質量％となるように調整して得た。この防曇剤を用いた以外は実施例１と同様行った。表２にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。金型汚染性に劣ることが分かる。
【００３６】
比較例４
防曇剤としては実施例１で用いたショ糖ラウリン酸エステルの３８質量％水溶液とメチルセルロースを用い、固形分割合でそれぞれ７５質量％と２５質量％となるように調整して得た。更にこの防曇剤を０．５質量％水溶液に希釈して、シート表面の防曇剤の固形分が０．０２ｇ／ｍ2 に塗布したシートを得た。このシートを用いた以外は実施例１と同様行った。表２にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。防曇効果に劣ることが分かる。
【００３７】
比較例５
スチレン系樹脂シートにブタジエン系ゴムが無いシート厚み０．２５ｍｍの２軸延伸ＧＰポリスチレンシートを用いた。また、防曇剤としては実施例１で用いたショ糖ラウリン酸エステルの３８質量％水溶液を用い、ポリビニルピロリドン系（共）重合体に未反応ビニルピロリドンが１２００ｐｐｍであるポリビニルピロリドンを用い、ショ糖ラウリン酸エステルとポリビニルピロリドンの固形分割合をそれぞれ７８質量％と２２質量％となるように調整して得た。この防曇剤を用いた以外は実施例１と同様行った。表２にゴム変性スチレン系樹脂シート中のゴム分を質量％、ゴム粒子径をμｍ、防曇剤の固形分の配合割合を質量％で示し、得られた物性も示した。金型汚染性、強靱性に劣ることが分かる。
【００３８】
【表１】
【表２】
【発明の効果】
本発明の防曇性ゴム変性スチレン系樹脂シート及びその成形品はシートブロッキング防止、強靱性、及び防曇効果に優れているので食料品の包装等に広く使用でき、非常に有用である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an antifogging rubber-modified styrenic resin sheet excellent in sheet blocking prevention, toughness and antifogging effect, and a molded product thereof. More specifically, the present invention relates to a styrene resin sheet that is widely used in the field of packaging materials, and the like, and a molded product thereof, which has been imparted with characteristics excellent in sheet blocking prevention, toughness, and antifogging effect. .
[0002]
[Prior art]
Styrene-based resin sheets and molded products are widely used as packaging and covering materials, but because the surface is hydrophobic, the water that aggregates due to changes in temperature and humidity becomes minute water droplets and adheres to the surface. May occur. The cloudiness makes it difficult to distinguish the stored items, and when the product value is reduced, or when water drops grow and fall on the contents, they often cause poor quality and spoilage. In addition, in the process of forming a styrene resin sheet into a molded product, when the molded product is overlaid and trimmed, the molded product is often broken, which causes a decrease in productivity.
[0003]
In order to solve this problem, JP-A-5-287097 discloses a surface treatment agent containing a sucrose fatty acid ester, a silicone emulsion, a polysaccharide and / or a hydrophilic polymer, and JP-A-10-309785 discloses a sucrose. Although it is described that a mixture of a fatty acid ester and methyl cellulose is used, it cannot be said that the sheet is excellent in blocking prevention, toughness and antifogging effect.
[0004]
[Problems to be solved by the invention]
An object of this invention is to provide the styrene resin sheet excellent in the antiblocking of a sheet | seat, toughness, and an anti-fogging effect, and its molded article based on the above technical situations.
[0005]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the present inventors have reached the present invention by using an antifogging agent having a specific configuration. That is, the present invention provides a rubber-modified styrene resin sheet having a sucrose fatty acid ester of 76-99.9% by mass and an unreacted vinyl pyrrolidone content of 1000 ppm or less of 0.1-24 mass of a polyvinylpyrrolidone-based (co) polymer. The problem is solved by forming an antifogging rubber-modified styrene resin sheet obtained by surface treatment with an antifogging agent containing 1% and a molded product obtained using the sheet.
[0006]
The present invention is described in detail below.
The antifogging agent of the present invention essentially comprises a polyvinylpyrrolidone (co) polymer in which sucrose fatty acid ester and unreacted vinylpyrrolidone are 1000 ppm or less. Sucrose fatty acid ester is an ester of sucrose and a fatty acid. Examples of the fatty acid constituting the sucrose fatty acid ester include caproic acid, caprylic acid, lauric acid, myristylic acid, palmitic acid, stearic acid, behenic acid, and montanic acid, saturated fatty acids having about 6 to 30 carbon atoms, and lindenic acid. , Unsaturated fatty acids having about 10 to 24 carbon atoms such as palmitooleic acid, oleic acid, elaidic acid, isooleic acid, erucic acid, linoleic acid, linolenic acid and the like, and these fatty acids may be used alone or in combination. Among them, the fatty acid constituting the sucrose fatty acid ester is lauric acid, and the ratio as the lauric acid component is 50% by mass or more, more preferably 55% by mass or more, and particularly preferably 65% by mass or more. When the ratio as a lauric acid component is 50 mass% or more, the tendency to be excellent in surface treatment property and also in the antifogging effect is seen. The fatty acid constituting the sucrose fatty acid ester forms sucrose fatty acid ester from sucrose and fatty acid, but here refers to the fatty acid before forming the ester. These sucrose fatty acid esters can be used alone or in combination of one or more.
[0007]
The polyvinylpyrrolidone (co) polymer of the present invention is a polymer of a vinylpyrrolidone monomer and a copolymer of a vinylpyrrolidone monomer and a monomer copolymerizable with the vinylpyrrolidone monomer. is there.
[0008]
The vinyl pyrrolidone monomer used in the present invention is vinyl pyrrolidone and its derivatives, preferably vinyl pyrrolidone. These vinyl pyrrolidone monomers can be used in combination of at least one or more.
[0009]
Examples of the monomer copolymerizable with the vinylpyrrolidone monomer used in the present invention include vinyl acetate, vinyl imidazole, and vinyl caprolactam. The ratio of the vinyl pyrrolidone monomer and the monomer copolymerizable with the vinyl pyrrolidone monomer is not particularly limited, but the vinyl pyrrolidone monomer is preferably 30% by mass or more, more preferably Is 40% by mass or more, particularly preferably 60% by mass or more. When the vinylpyrrolidone monomer is 30% by mass or more, a tendency to be excellent in the antifogging effect is observed.
[0010]
The amount of unreacted vinylpyrrolidone present in the polyvinylpyrrolidone-based (co) polymer of the present invention is 1000 ppm or less. Preferably it is 500 ppm or less, More preferably, it is 300 ppm or less, Most preferably, it is 100 ppm or less. If the amount of unreacted vinyl pyrrolidone is more than 1000 ppm, the mold is easily contaminated during sheet molding, and the transparency of the molded product is lowered. Further, the unreacted vinyl pyrrolidone in the antifogging agent composition of the present invention comprising a sucrose fatty acid ester and a polyvinyl pyrrolidone (co) polymer is preferably 200 ppm or less, more preferably 100 ppm or less.
[0011]
The ratio of the sucrose fatty acid ester and the polyvinyl pyrrolidone (co) polymer in the antifogging agent of the present invention is 76-99.9% by mass of the sucrose fatty acid ester and the polyvinyl pyrrolidone (co) polymer 0.1. 24% by mass. Preferably, the sucrose fatty acid ester is 80 to 99.5% by mass and the polyvinyl pyrrolidone-based (co) polymer is 0.5 to 20% by mass, more preferably the sucrose fatty acid ester is 85 to 98% by mass and the polyvinyl pyrrolidone-based (co-polymer). ) 2 to 15% by mass of polymer, particularly preferably 90 to 97% by mass of sucrose fatty acid ester and 3 to 10% by mass of polyvinylpyrrolidone (co) polymer. When the amount of sucrose fatty acid ester is less than 76% by mass, the antifogging effect is poor. Moreover, when there is less than 0.1 mass% polyvinylpyrrolidone type (co) polymer, it will be inferior to the sustainability of an anti-fogging effect, and when it exceeds 24 mass%, it will be inferior to sheet blocking prevention.
[0012]
When the surface of the rubber-modified styrene resin sheet is treated with an antifogging agent, it is used as a solution in which a sucrose fatty acid ester and a polyvinylpyrrolidone (co) polymer are dissolved in a solvent. As the solvent, water, alcohol or the like is used, but is not particularly limited thereto. Water is preferable for handling. In that case, the solution concentration of the sucrose fatty acid ester and the polyvinylpyrrolidone-based (co) polymer is not particularly limited, but is preferably 0.01 to 10% by mass.
[0013]
The rubber-modified styrene resin sheet used in the antifogging rubber-modified styrene resin sheet of the present invention is a sheet before being treated with an antifogging agent obtained by molding and processing a rubber-modified styrene resin. The rubber-modified styrenic resin includes a copolymer obtained by copolymerizing a styrene monomer and / or a monomer copolymerizable with a styrene monomer in the presence of a butadiene rubber, and a mixture thereof. Can be mentioned.
[0014]
Styrene monomers used in the above copolymer include styrene, α-methyl styrene, p-methyl styrene, vinyl toluene, t-butyl styrene, etc., and can be copolymerized with styrene monomers. Examples of such monomers include acrylic acid, ethyl acrylate, methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, acrylonitrile, methacrylic acid, ethyl methacrylate, methyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, Examples include 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene) and the like.
Further, examples of the butadiene rubber include high-cis polybutadiene, low-cis polybutadiene, styrene-butadiene rubber, styrene-butadiene block rubber, styrene-butadiene-styrene block rubber, and partially hydrogenated polybutadiene rubber. Note that at least one monomer or butadiene rubber used for polymerization can be used. These rubber-modified styrene resins are preferably high-impact polystyrene (HIPS) obtained by polymerizing styrene in the presence of at least one of high-cis polybutadiene, low-cis polybutadiene, and styrene-butadiene-styrene block rubber.
[0015]
The rubber content and the rubber particle diameter in the rubber-modified styrene resin and the rubber-modified styrene resin sheet are not particularly limited, but are more preferable as long as the transparency is not impaired. When emphasizing transparency, the rubber content is preferably 0.01 to 10% by mass, more preferably 0.1 to 5% by mass. When the rubber content is less than 0.01% by mass, the toughness tends to be inferior, and when it is more than 10% by mass, the transparency tends to be inferior. The rubber particle diameter is preferably 0.01 μm to 10 μm, and more preferably 0.1 μm to 5 μm. When the rubber particle diameter is smaller than 0.01 μm, the toughness tends to be inferior, and when it is larger than 10 μm, the transparency tends to be inferior.
[0016]
The method for processing the rubber-modified styrenic resin into a sheet is not particularly limited, and examples thereof include conventional methods such as a uniaxial stretching method, a biaxial stretching method, a multiaxial stretching method, a coextrusion method, and a lamination method. In addition, for the antifogging treatment of the sheet, it is preferable to modify the surface of the sheet by a corona discharge treatment method, an ozone treatment method, a plasma treatment method or the like.
[0017]
The method for treating the antifogging agent treatment liquid into the rubber-modified styrene resin sheet is not particularly limited, and a method of applying using a roll coater, a knife coater, a gravure roll coater or the like can be used. Moreover, spraying, immersion, etc. can also be employ | adopted.
[0018]
The solid content of the antifogging agent on the surface of the rubber-modified styrene resin sheet of the present invention treated with the antifogging agent is preferably 0.005 to 0.5 g / m 2 , more preferably 0.01 to 0.45 g / m 2 , Most preferably, it is 0.01-0.4 g / m < 2 >. Solids of rubber-modified styrenic resin sheet antifogging agents tended to be inferior in low antifogging effect than 0.005 g / m 2, also uneven coating of more sheet surface than 0.5 g / m 2 Begins to stand out.
[0019]
The antifogging rubber-modified styrenic resin sheet of the present invention is used as it is as a food packaging or covering material. The thickness of the antifogging rubber-modified styrene resin sheet is not particularly limited and is generally 100 μm to 10 mm. This sheet is molded and used for containers. Moreover, when importance is attached to the transparency of the antifogging rubber-modified styrene resin sheet, the transparency of the antifogging rubber-modified styrene is preferably 10% or less.
[0020]
The molded product of the present invention is a lid container or a food pack for packaging a food product molded from an antifogging rubber-modified styrenic resin sheet using pressure forming, vacuum forming, vacuum pressure forming or the like.
[0021]
【Example】
EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.
In addition, the physical-property measurement in an Example was implemented as follows.
(1) Rubber content: Measured using 90 MHz H1-NMR manufactured by JEOL Ltd., using a rubber-modified styrene resin sheet as a sample.
(2) Rubber particle diameter: It was measured using a photograph taken with a transmission electron microscope manufactured by JEOL Ltd., in a gear oven, a rubber-modified styrenic resin sheet that had been heated and shrunk at 130 ° C. for 1 hour. The rubber particle diameter is represented by the average volume diameter ([D]) calculated by the equation (1).
[Expression 1]
(3) Amount of unreacted vinyl pyrrolidone: As a sample, 10 g of the individual polyvinyl pyrrolidone (co) polymer is dissolved in 100 ml of pure water, and 2 g of sodium acetate and 50 ml of methanol are added. To this solution, titrate 0.1N iodine solution until the color of iodine disappears, add 10 ml, and leave it for about 30 minutes until the reaction is completely completed (the total amount of iodine is Aml). Thereafter, titration is performed with 0.1N sodium thiosulfate (consumption amount of sodium thiosulfate is Bml). In addition, starch test solution is used as an indicator. The amount of unreacted vinyl pyrrolidone is obtained from the following formula.
Vinylpyrrolidone amount (%) = {(A−B) × 0.555 / (sample amount (g)}
[0022]
(4) Transparency of sheet: Antifogging property in which antifogging agent is applied to 0.25 mm thick biaxially stretched rubber-modified styrene resin sheet stretched 2.5 times in the vertical direction and 2.5 times in the horizontal direction. The haze of the rubber-modified styrene resin sheet was measured with a measuring machine NDH-1001DP manufactured by Nippon Denshoku Industries Co., Ltd.
◎: Haze is less than 10% ○: Haze is 10% or more and less than 20% Δ: Haze is 20% or more [0023]
(5) Mold fouling property: The antifogging rubber-modified styrene resin sheet obtained in (4) is flattened at a molding temperature of 130 ° C using a vacuum / pressure forming machine PK400 manufactured by Kansai Automatic Molding Machine Co., Ltd. A simple lid container (200 mm long × 120 mm wide × 50 mm high) was molded into 200 shots. After molding 200 shots, the contamination of the mold was visually evaluated.
○: Mold contamination is hardly seen.
Δ: About half of mold contamination is observed.
X: Mold contamination is mostly observed.
[0024]
(6) Sheet blocking property: The antifogging rubber-modified styrene resin sheet coated with the antifogging agent obtained in (4) and the rubber-modified styrene resin sheet not coated with anything are stacked in an area of 10 cm × 10 cm, respectively. The rubber-modified styrenic resin sheet was peeled off after being allowed to stand under a load of 10 MPa for 24 hours. The sheet state at that time was visually evaluated from all 10 combinations.
◎: No whitening on sheet ○: Whitening occurs in less than 10% of sheet area Δ: Whitening occurs in 10-40% of sheet area ×: Whitening occurs in excess of 40% of sheet area
(7) Anti-fogging effect {circle around (1)}: After pasting each one of the lid containers obtained in (5) on a PSP (polystyrene paper) container filled with hot water at a temperature of 45 ° C., the temperature is further lowered to 5 ° C. Left in the refrigerator for 30 minutes. Thereafter, the cloudiness of the lid container was visually evaluated. In addition, it evaluated using 10 containers of 21 to 30 shots.
A: Almost no cloudiness is observed.
○: Some cloudiness is seen.
Δ: About half of cloudiness is observed.
X: Mostly cloudy.
(8) Antifogging effect {circle around (2)}: After evaluating the antifogging effect {circle around (1)}, the lid container was reciprocated 20 times up and down 10 cm (original position and 10 cm above the position) at a speed of 30 cm / sec. At that time, the number of drops dropped was counted. A smaller water droplet count indicates better anti-fogging properties.
[0026]
(9) Toughness evaluation: When 20 lid containers with ears obtained in (5) were stacked and 20 ears were trimmed at once, a total of 5 operations were performed for 100 lid containers. The number of cracks in the lid container was counted. It shows that it is excellent in toughness, so that the count number which the crack generate | occur | produced is small.
[0027]
Example 1
As the rubber-modified styrene resin sheet, a biaxially stretched impact-resistant polystyrene sheet having a rubber content of 2.5% by mass, a rubber particle diameter of 0.2 μm, and a sheet thickness of 0.25 mm was used. Further, as an antifogging agent, 70% by mass of the fatty acid constituting the sucrose fatty acid ester is sucrose lauric acid ester in which lauric acid is used, and a 38% by mass aqueous solution thereof is used. Using polyvinyl pyrrolidone having an unreacted vinyl pyrrolidone of 60 ppm, the sucrose laurate and polyvinyl pyrrolidone were adjusted to a solid content ratio of 96% by mass and 4% by mass. Further, this antifogging agent was diluted with a 1.5% by mass aqueous solution to obtain a sheet coated with a solid content of the antifogging agent on the sheet surface of 0.06 g / m 2 . Moreover, the lid | cover container (200 mm length x 120 mm width x 50 mm height) was shape | molded using the sheet | seat. In addition, DK ester S-L18A manufactured by Daiichi Kogyo Seiyaku Co., Ltd. was used for a 38 mass% aqueous solution of sucrose laurate, and Rubiscol K17 manufactured by BASF Japan was used for polyvinylpyrrolidone. Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties.
[0028]
Example 2
As an antifogging agent, a sucrose fatty acid ester using 38 mass% aqueous solution of sucrose lauric acid ester used in Example 1, and a pellet of sucrose myristic acid ester in which 95 mass% of the constituent fatty acid is myristic acid, The polyvinyl pyrrolidone used in Example 1 was used as the polyvinyl pyrrolidone-based (co) polymer. It was obtained by adjusting the solid content ratios of sucrose laurate, sucrose myristate, and polyvinylpyrrolidone to 86 mass%, 6 mass%, and 8 mass%, respectively. It carried out similarly to Example 1 except having used this antifogging agent. In addition, Dai-ichi Kogyo Seiyaku M-160 was used for sucrose myristic acid ester. Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties.
[0029]
Example 3
As an antifogging agent, a 38% mass aqueous solution of sucrose laurate used in Example 1 was used as the sucrose fatty acid ester, and the polyvinylpyrrolidone-based (co) polymer had 40 ppm of unreacted vinylpyrrolidone and vinylpyrrolidone and vinyl acetate. Polyvinylpyrrolidone-vinyl acetate copolymer having a proportion of 70% by mass and 30% by mass was used. The sucrose lauric acid ester and the polyvinylpyrrolidone-vinyl acetate copolymer were obtained by adjusting the solid content ratios to 88% by mass and 12% by mass, respectively. Further, this antifogging agent was diluted with a 0.25% by mass aqueous solution to obtain a sheet coated with a solid content of the antifogging agent on the sheet surface of 0.01 g / m 2 . The same operation as in Example 1 was performed except that this sheet was used. In addition, BASF Japan rubiscol VA64P was used for the polyvinylpyrrolidone-vinyl acetate copolymer. Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties.
[0030]
Example 4
As the antifogging agent, a sucrose fatty acid ester used is a 38% by mass aqueous solution of the sucrose lauric acid ester used in Example 1, and a sucrose stearate in which 70% by mass of the fatty acid is stearic acid. The polyvinyl pyrrolidone used in Example 1 and the polyvinyl pyrrolidone-vinyl acetate copolymer used in Example 3 were used for the system (co) polymer. The solid content ratios of sucrose laurate, sucrose stearate, polyvinylpyrrolidone, and polyvinylpyrrolidone-vinyl acetate copolymer were adjusted to 65 mass%, 15 mass%, 10 mass%, and 10 mass%, respectively. I got it. It carried out similarly to Example 1 except having used this antifogging agent. In addition, the above-mentioned thing was used for each component substance which comprises an antifogging agent. Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties.
[0031]
Example 5
Example except that a biaxially stretched methyl methacrylate-butadiene-styrene copolymer sheet having a rubber content of 6.0% by mass, a rubber particle diameter of 1.0 μm, and a sheet thickness of 0.25 mm was used as the rubber-modified styrene resin sheet. 1 was performed. Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties.
[0032]
Example 6
The same procedure as in Example 1 was performed except that a biaxially stretched impact-resistant polystyrene sheet having a rubber content of 0.5% by mass, a rubber particle diameter of 0.08 μm, and a sheet thickness of 0.4 mm was used as the rubber-modified styrene resin sheet. . Table 1 shows the rubber content in the rubber-modified styrenic resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties.
[0033]
Comparative Example 1
As the anti-fogging agent, a 38% by mass aqueous solution of the sucrose laurate used in Example 1 was used, and the polyvinyl pyrrolidone used in Example 1 was used as the polyvinyl pyrrolidone (co) polymer. It was obtained by adjusting the solid content ratio of polyvinylpyrrolidone to 5% by mass and 95% by mass, respectively. The same procedure as in Example 1 was performed except that this antifogging agent was used. Table 2 shows the rubber content in the rubber-modified styrene-based resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties. It turns out that it is inferior to blocking prevention and an anti-fogging effect.
[0034]
Comparative Example 2
As the rubber-modified styrene resin sheet, a biaxially stretched impact-resistant polystyrene sheet having a rubber content of 15% by mass, a rubber particle diameter of 1.5 μm, and a sheet thickness of 0.25 mm was used. Further, as the antifogging agent, the 38% by mass aqueous solution of sucrose laurate used in Example 1 was used, and the polyvinylpyrrolidone-based (co) polymer had 2000 ppm of unreacted vinylpyrrolidone and the weight average molecular weight was 1,200,000. Polyvinylpyrrolidone was used, and the solid content ratio of sucrose laurate and polyvinylpyrrolidone was adjusted to 67% by mass and 33% by mass, respectively. Further, this antifogging agent was diluted with a 3% by mass aqueous solution to obtain a sheet coated with a solid content of the antifogging agent on the sheet surface of 0.03 g / m 2 . The same operation as in Example 1 was performed except that this sheet was used. Table 2 shows the rubber content in the rubber-modified styrene-based resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties. It turns out that it is inferior to a mold pollution property, blocking prevention, and an anti-fogging effect.
[0035]
Comparative Example 3
As the antifogging agent, the 38 mass% aqueous solution of sucrose laurate used in Example 1 was used, and polyvinylpyrrolidone having 1200 ppm of unreacted vinylpyrrolidone was used as the polyvinylpyrrolidone (co) polymer, and sucrose lauric acid was used. The solid content ratio of the ester and polyvinylpyrrolidone was adjusted to 78% by mass and 22% by mass, respectively. The same procedure as in Example 1 was performed except that this antifogging agent was used. Table 2 shows the rubber content in the rubber-modified styrene-based resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties. It can be seen that the mold contamination is poor.
[0036]
Comparative Example 4
As the antifogging agent, the 38% by mass aqueous solution of sucrose lauric acid ester used in Example 1 and methylcellulose were used, and the solid content ratio was adjusted to 75% by mass and 25% by mass, respectively. Further, this antifogging agent was diluted to a 0.5% by mass aqueous solution to obtain a sheet coated with a solid content of the antifogging agent on the sheet surface of 0.02 g / m 2 . The same operation as in Example 1 was performed except that this sheet was used. Table 2 shows the rubber content in the rubber-modified styrene-based resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties. It turns out that it is inferior to an anti-fogging effect.
[0037]
Comparative Example 5
A biaxially stretched GP polystyrene sheet having a sheet thickness of 0.25 mm without butadiene rubber was used as the styrene resin sheet. Further, as the antifogging agent, the 38 mass% aqueous solution of sucrose laurate used in Example 1 was used, and polyvinyl pyrrolidone having 1200 ppm of unreacted vinyl pyrrolidone was used as the polyvinyl pyrrolidone-based (co) polymer. It was obtained by adjusting the solid content ratio of lauric acid ester and polyvinylpyrrolidone to 78% by mass and 22% by mass, respectively. The same procedure as in Example 1 was performed except that this antifogging agent was used. Table 2 shows the rubber content in the rubber-modified styrene-based resin sheet in mass%, the rubber particle diameter in μm, the blending ratio of the solid content of the antifogging agent in mass%, and the obtained physical properties. It can be seen that the mold contamination and toughness are inferior.
[0038]
[Table 1]
[Table 2]
【The invention's effect】
The antifogging rubber-modified styrenic resin sheet and its molded product of the present invention are excellent in sheet blocking prevention, toughness, and antifogging effect, and thus can be widely used for food packaging and the like and are very useful.
Claims (7)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001221250A JP3781645B2 (en) | 2001-07-23 | 2001-07-23 | Antifogging rubber-modified styrene resin sheet and molded product thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001221250A JP3781645B2 (en) | 2001-07-23 | 2001-07-23 | Antifogging rubber-modified styrene resin sheet and molded product thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2003026833A JP2003026833A (en) | 2003-01-29 |
| JP3781645B2 true JP3781645B2 (en) | 2006-05-31 |
Family
ID=19054941
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001221250A Expired - Fee Related JP3781645B2 (en) | 2001-07-23 | 2001-07-23 | Antifogging rubber-modified styrene resin sheet and molded product thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3781645B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4991095B2 (en) * | 2003-04-04 | 2012-08-01 | ダイセルポリマー株式会社 | Anti-fogging sheet and container using the same |
| JP4515844B2 (en) * | 2003-11-20 | 2010-08-04 | 三菱樹脂株式会社 | Anti-fogging resin sheet and anti-fogging food packaging container using the same |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000280410A (en) * | 1999-03-31 | 2000-10-10 | Chuo Kagaku Co Ltd | Anti-fogging sheet material and anti-fogging food packaging container |
-
2001
- 2001-07-23 JP JP2001221250A patent/JP3781645B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2003026833A (en) | 2003-01-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9884931B2 (en) | Vinylidene chloride copolymer latex and film for blister pack | |
| JP4905971B2 (en) | Anti-fogging styrene resin sheet and its molded product | |
| JPH05287097A (en) | Surface treatment, coated polymer film and production of the same | |
| JP3781645B2 (en) | Antifogging rubber-modified styrene resin sheet and molded product thereof | |
| JP3810284B2 (en) | Antifogging styrene-based transparent resin sheet and molded product thereof | |
| JP3904545B2 (en) | Styrenic resin sheet, molded product thereof, and manufacturing method thereof | |
| JP3721349B2 (en) | Antifogging styrene-based transparent resin sheet and molded product thereof | |
| JP6306871B2 (en) | Polystyrene resin sheet suitable for microwave heating applications and molded containers thereof | |
| JP6807597B2 (en) | Matte barrier polyamide film and its manufacturing method | |
| JP2010155612A (en) | Sealing member | |
| JPH0839718A (en) | Vacuum-deposited composite film and its production | |
| JP3497613B2 (en) | Styrene resin sheet / film | |
| JPS6365682B2 (en) | ||
| JP4787480B2 (en) | Resin modifier and thermoplastic resin composition | |
| JPS6239619B2 (en) | ||
| JP2003213024A (en) | Antifogging thermoplastic transparent resin sheet and moldings therefrom | |
| JP2000309645A (en) | Biaxially oriented styrene-based resin sheet | |
| JP2016535141A (en) | Process for producing vinylidene chloride-based heteropolymers | |
| JPH0496980A (en) | Latex for coating of polystyrene | |
| JP2001049016A (en) | Anti-fogging, rubber modified styrenic resin sheet and molded article therefor | |
| JP7010624B2 (en) | Styrene-based resin film for thermal laminating, laminated sheets, containers, and packaging | |
| JP2019196213A (en) | Packaging body | |
| JP2001164012A (en) | Antifogging rubber-modified styrene-based resin sheet and molded product thereof | |
| JP2000026637A (en) | Antifogging rubber-modified styrene resin sheet and molded product thereof | |
| JP2018043507A (en) | Multilayer sheet for ptp, and ptp using the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20050614 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20050621 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20050913 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20051213 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20060307 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20060307 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100317 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110317 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120317 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130317 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130317 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140317 Year of fee payment: 8 |
|
| LAPS | Cancellation because of no payment of annual fees |