JP2004051946A - Sheet and its laminated sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a colorless and transparent sheet excellent in heat resistance, which excels in scuff resistance, oil resistance, chemical resistance, gas barrier properties and weatherability in good balance, and a laminated sheet which excels in colorless transparency, scuff resistance, oil resistance, chemical resistance, gas barrier and weatherability in good balance. <P>SOLUTION: The sheet comprises a thermoplastic copolymer comprising a glutaric anhydride unit (i) expressed by formula (1) and an unsaturated alkyl carboxylate unit (ii), or a thermoplastic copolymer comprising the unit (i), the unit (ii) and an unsaturated carboxylic acid unit (iii), or a thermoplastic copolymer comprising the units (i) and (ii), or (i), (ii) and (iii) and further, another vinyl monomer unit (iv) containing no aromatic ring with ≤0.5 absorbance at 280 nm and ≥130°C glass transition temperature, where in formula (1), R<SP>1</SP>and R<SP>2</SP>are the same or different and each denotes a hydrogen atom or a 1-5C alkyl group. <P>COPYRIGHT: (C)2004,JPO

Description

【００１３】
（上記式中、Ｒ^１、Ｒ^２は、同一または相異なる水素原子または炭素数１〜５のアルキル基を表す）
［２］不飽和カルボン酸アルキルエステル単量体および不飽和カルボン酸単量体を含む単量体混合物を、９５℃以下の温度で重合して（Ｃ）原共重合体を得、次いで（Ｃ）原共重合体を加熱し、（イ）脱アルコール反応および／または（ロ）脱水反応により、（Ａ）熱可塑性共重合体を得ることを特徴とする上記［１］記載のシート、
［３］（ｉｉｉ）不飽和カルボン酸単位が、下記一般式（２）で表される構造を有する上記［１］または［２］記載のシート、
【００１４】
【化５】

【００１５】
（ただし、Ｒ^３は水素又は炭素数１〜５のアルキル基を表す）
［４］（ｉｉ）不飽和カルボン酸アルキルエステル単位が、下記一般式（３）で表される構造を有する上記［１］〜［３］いずれか記載のシート、
【００１６】
【化６】

【００１７】
（ただし、Ｒ^４は水素又は炭素数１〜５のアルキル基を表し、Ｒ^５は炭素数１〜６の脂肪族若しくは脂環式炭化水素基又は１個以上炭素数以下の数の水酸基若しくはハロゲンで置換された炭素数１〜６の脂肪族若しくは脂環式炭化水素基を表す）
［５］表面硬度が、鉛筆硬度で４Ｈ以上であることを特徴とする上記［１］〜［４］いずれか記載のシート、
［６］表面層の少なくとも一方が、上記［１］〜［４］いずれか記載の（Ａ）熱可塑性共重合体からなる層である積層シート、
［７］（Ａ）熱可塑性共重合体からなる表面層の表面硬度が、鉛筆硬度で４Ｈ以上であることを特徴とする上記［６］記載の積層シート、
［８］さらに（Ｂ）基材を有し、該基材が熱可塑性樹脂であることを特徴とする上記［６］または［７］いずれか記載の積層シート、
［９］熱可塑性樹脂が、透明樹脂であることを特徴とする上記［８］記載の積層シート、
［１０］（Ａ）熱可塑性共重合体と熱可塑性樹脂とを、一体に共押出することを特徴とする上記［６］〜［９］いずれか記載の積層シートの製造方法
を提供するものである。
【００１８】
【発明の実施の形態】
以下、本発明のシートおよび積層シートについて具体的に説明する。
【００１９】
本発明のシートまたは積層シートに使用される（Ａ）熱可塑性共重合体は、（ｉ）下記一般式（１）
【００２０】
【化７】

【００２１】
（上記式中、Ｒ^１、Ｒ^２は、同一または相異なる水素原子または炭素数１〜５のアルキル基を表す）
で表されるグルタル酸無水物単位、（ｉｉ）不飽和カルボン酸アルキルエステル系単位からなる熱可塑性共重合体、若しくは上記（ｉ）、（ｉｉ）の単位および（ｉｉｉ）不飽和カルボン酸単位を有する熱可塑性共重合体、または上記（ｉ）、（ｉｉ）の単位若しくは上記（ｉ）、（ｉｉ）、（ｉｉｉ）の単位および（ｉｖ）芳香環を含まないその他ビニル系単量体からなる熱可塑性共重合体であることを特徴とするものであり、これらは一種または二種以上で用いることができる。
【００２２】
本発明に用いる（Ａ）熱可塑性共重合体の製造方法に特に制限はないが、基本的には以下に示す方法により製造することができる。すなわち、後の加熱工程により上記一般式（１）で表される（ｉ）グルタル酸無水物単位を与える不飽和カルボン酸アルキルエステル単量体及び不飽和カルボン酸単量体と、その他のビニル系単量体単位を含む場合には該単位を与えるビニル系単量体とを共重合させ、（Ｃ）原共重合体とした後、かかる（Ｃ）原共重合体を適当な触媒の存在下あるいは非存在下で加熱し、（イ）脱アルコールおよび／または（ロ）脱水による分子内環化反応を行わせることにより本発明に用いる（Ａ）熱可塑性共重合体を製造することができる。この場合、典型的には、（Ｃ）原共重合体を加熱することにより２単位の（ｉｉｉ）不飽和カルボン酸単位のカルボキシル基からの水の脱離により、あるいは、隣接する１単位の（ｉｉｉ）不飽和カルボン酸単位と１単位の（ｉｉ）不飽和カルボン酸アルキルエステル単位からアルコールの脱離により１単位の（ｉ）グルタル酸無水物単位が生成される。
【００２３】
この際に用いられる不飽和カルボン酸単量体としては特に制限はなく、他のビニル化合物と共重合させることが可能ないずれの不飽和カルボン酸単量体も使用可能である。好ましい不飽和カルボン酸単量体として、下記一般式（４）
【００２４】
【化８】

【００２５】
（ただし、Ｒ^３は水素又は炭素数１〜５のアルキル基を表す）
で表される化合物、マレイン酸、及びさらには無水マレイン酸の加水分解物などが挙げられるが、特に熱安定性が優れる点でアクリル酸、メタクリル酸が好ましく、より好ましくはメタクリル酸である。これらはその１種または２種以上用いることができる。なお、上記一般式（４）で表される不飽和カルボン酸単量体は、共重合すると上記一般式（２）で表される構造の（ｉｉｉ）不飽和カルボン酸単位を与える。
【００２６】
また不飽和カルボン酸アルキルエステル系単量体としては特に制限はないが、好ましい例として、下記一般式（５）で表されるものを挙げることができる。
【００２７】
【化９】

【００２８】
（ただし、Ｒ^４は水素又は炭素数１〜５のアルキル基を表し、Ｒ^５は炭素数１〜６の脂肪族若しくは脂環式炭化水素基又は１個以上炭素数以下の数の水酸基若しくはハロゲンで置換された炭素数１〜６の脂肪族若しくは脂環式炭化水素基を表す）
これらのうち、炭素数１〜６の脂肪族若しくは脂環式炭化水素基又は置換基を有する該炭化水素基を持つアクリル酸エステルおよび／またはメタクリル酸エステルが特に好適である。なお、上記一般式（５）で表される不飽和カルボン酸アルキルエステル単量体は、共重合すると上記一般式（３）で表される構造の（ｉｉ）不飽和カルボン酸アルキルエステル単位を与える。
【００２９】
不飽和カルボン酸アルキルエステル単量体の好ましい具体例としては、（メタ）アクリル酸メチル、（メタ）アクリル酸エチル、（メタ）アクリル酸ｎ−プロピル、（メタ）アクリル酸ｎ−ブチル、（メタ）アクリル酸ｔ−ブチル、（メタ）アクリル酸ｎ−へキシル、（メタ）アクリル酸シクロヘキシル、（メタ）アクリル酸クロロメチル、（メタ）アクリル酸２−クロロエチル、（メタ）アクリル酸２−ヒドロキシエチル、（メタ）アクリル酸３−ヒドロキシプロピル、（メタ）アクリル酸２，３，４，５，６−ペンタヒドロキシヘキシルおよび（メタ）アクリル酸２，３，４，５−テトラヒドロキシペンチルなどが挙げられ、なかでもメタクリル酸メチルが最も好ましく用いられる。これらはその１種または２種以上を用いることができる。
【００３０】
また、本発明で用いる（Ａ）熱可塑性共重合体の製造においては、本発明の効果を損なわない範囲で、芳香環を含まないその他のビニル系単量体を用いてもかまわない。芳香環を含まないその他のビニル系単量体の好ましい具体例としては、アクリロニトリル、メタクリロニトリル、エタクリロニトリルなどのシアン化ビニル系単量体、アリルグリシジルエーテル、無水マレイン酸、無水イタコン酸、Ｎ−メチルマレイミド、Ｎ−エチルマレイミド、Ｎ−シクロヘキシルマレイミド、アクリルアミド、メタクリルアミド、Ｎ−メチルアクリルアミド、ブトキシメチルアクリルアミド、Ｎ−プロピルメタクリルアミド、アクリル酸アミノエチル、アクリル酸プロピルアミノエチル、メタクリル酸ジメチルアミノエチル、メタクリル酸エチルアミノプロピル、メタクリル酸シクロヘキシルアミノエチル、Ｎ−ビニルジエチルアミン、Ｎ−アセチルビニルアミン、アリルアミン、メタアリルアミン、Ｎ−メチルアリルアミン、２−イソプロペニル−オキサゾリン、２−ビニル−オキサゾリン、２−アクロイル−オキサゾリンなどを挙げることができる。これらは単独ないし２種以上を用いることができる。
【００３１】
芳香環を含むビニル系単量体を共重合すると、耐擦傷性、耐油性、耐薬品性、耐候性が低下する傾向にあるため、共重合しないことが好ましいが、本発明の効果を損なわない範囲であれば差し支えない。かかる芳香環を含むビニル系単量体としては、Ｎ−フェニルマレイミド、メタクリル酸フェニルアミノエチル等があげられる。なお、スチレン、α−メチルスチレン、ｐ−グリシジルスチレン、スチレン−ｐ−グリシジルエーテル、ｐ−アミノスチレン、２−スチリル−オキサゾリンなどの芳香族ビニル系単量体については、特に上記特性が低下する傾向が強いため、共重合しないことが好ましいが、共重合する場合には１重量％未満にとどめる必要がある。
【００３２】
（Ｃ）原共重合体の重合方法については、基本的にはラジカル重合による、塊状重合、溶液重合、懸濁重合、乳化重合等の公知の重合方法を用いることができるが、不純物がより少ない点で溶液重合、塊状重合、懸濁重合が特に好ましい。
【００３３】
また、加熱処理後の熱可塑性共重合体の吸光度を本発明の範囲内に制御するために、（Ｃ）原共重合体は通常９５℃以下の温度で重合されるが、加熱処理後の無色透明性をさらに向上させるためには９０℃以下の重合温度で製造することが好ましく、より好ましい重合温度は８５℃以下であり、さらに好ましくは８０℃以下であり、特に好ましくは７５℃以下であり、最も好ましくは７０℃以下である。また、重合温度の下限は、重合が進行する温度であれば、特に制限はないが、重合速度を考慮した生産性の面から、通常５０℃以上、好ましくは６０℃以上である。重合収率あるいは重合速度を向上させる目的で、重合進行に従い重合温度を昇温することも可能であるが、この場合も昇温する上限温度は通常９５℃以下、好ましくは９０℃以下に制御する。重合開始温度も７５℃以下の比較的低温で行うことが好ましい。また重合時間は、必要な重合率を得るのに十分な時間であれば特に制限はないが、生産効率の点から６０〜３６０分間の範囲が好ましく、９０〜１８０分間の範囲が特に好ましい。
【００３４】
本発明において、（Ｃ）原共重合体の製造時に用いられるこれらの単量体混合物の好ましい割合は、該単量体混合物を１００重量％として、不飽和カルボン酸系単量体が１５〜５０重量％、より好ましくは２０〜４５重量％、不飽和カルボン酸アルキルエステル系単量体は好ましくは５０〜８５重量％、より好ましくは５５〜８０重量％である。これらに共重合可能な芳香環を含まないその他のビニル系単量体を用いる場合、その好ましい割合は０〜３５重量％であるが、芳香族ビニル化合物を共重合する場合は、本発明の耐擦傷性、耐油性、耐薬品性および耐候性の向上を損なわない範囲である１重量％未満である必要がある。
【００３５】
不飽和カルボン酸系単量体量が１５重量％未満の場合には、（Ｃ）原共重合体の加熱による上記一般式（１）で表されるグルタル酸無水物単位の生成量が少なくなり、耐熱性向上効果が小さくなる傾向がある。一方、不飽和カルボン酸系単量体量が５０重量％を超える場合には、（Ｃ）原共重合体の加熱による環化反応後に、不飽和カルボン酸単位が多量に残存する傾向があり、無色透明性、滞留安定性が低下する傾向がある。
【００３６】
本発明における（Ｃ）原共重合体を加熱し、（イ）脱アルコールおよび／または（ロ）脱水による分子内環化反応を行い、グルタル酸無水物単位を含有する熱可塑性重合体を製造する方法は、特に制限はないが、ベントを有する加熱した押出機に通して製造する方法や窒素気流中または真空下で加熱脱気できる装置内で製造する方法が好ましい。なお、上記の方法により加熱脱気する温度は、（イ）脱アルコールおよび／または（ロ）脱水による分子内環化反応が生じる温度であれば特に限定されないが、好ましくは１８０〜３００℃の範囲、特に２００〜２８０℃の範囲が好ましい。また、この際の加熱脱気する時間は特に限定されず、所望する共重合組成に応じて適宜設定可能であるが、通常、１分間〜６０分間の範囲が好ましい。
【００３７】
さらに本発明では、（Ｃ）原共重合体を上記方法等により加熱する際にグルタル酸無水物への環化反応を促進させる触媒として、酸、塩基、塩化合物の１種以上を添加することができる。その添加量は特に制限はなく、（Ｃ）原共重合体１００重量部に対し、０．０１〜１重量部程度が適当である。また、これら酸、塩基、塩化合物の種類についても特に制限はなく、酸触媒としては、塩酸、硫酸、ｐ−トルエンスルホン酸、リン酸、亜リン酸、フェニルホスホン酸、リン酸メチル等が挙げられる。塩基性触媒としては、金属水酸化物、アミン類、イミン類、アルカリ金属誘導体、アルコキシド類、水酸化アンモニウム塩等が挙げられる。さらに、塩系触媒としては、酢酸金属塩、ステアリン酸金属塩、炭酸金属塩等が挙げられる。塩系触媒の中には、水溶液とすることにより酸性あるいは塩基性を示すものが含まれるが、これらは塩系触媒とし、酸触媒あるいは塩基性触媒と区別する。これら触媒は本発明の目的を損なわない範囲で１種または２種以上添加することができる。
【００３８】
本発明に使用される（Ａ）熱可塑性共重合体中の前記一般式（１）で表される（ｉ）グルタル酸無水物単位の含有量は、ガラス転移温度が本発明の範囲内であれば、特に制限はないが、好ましくは（Ａ）熱可塑性共重合体１００重量％中に５〜５０重量％、より好ましくは１０〜４５重量％である。グルタル酸無水物単位が５重量％未満である場合、耐熱性向上効果が小さく、また十分な耐候性が得られない傾向がある。また、該グルタル酸無水物単位の定量には、赤外分光光度計が使用できる。グルタル酸無水物単位は、１８００ｃｍ^−１及び１７６０ｃｍ^−１の吸収が特徴的であり、不飽和カルボン酸単位や不飽和カルボン酸アルキルエステル単位から区別することができる。なお、本発明の共重合体中に含有される各成分の定量には、上記した赤外分光光度計による方法とともに、^１Ｈ−ＮＭＲによる方法を使用することができる。例えば、グルタル酸無水物単位、メタクリル酸、メタクリル酸メチルからなる共重合体の場合、スペクトルの帰属を、０．５〜１．５ｐｐｍのピークがメタクリル酸、メタクリル酸メチルおよびグルタル酸無水物環化合物のα−メチル基の水素、１．６〜２．１ｐｐｍのピークはポリマー主鎖のメチレン基の水素、３．５ｐｐｍのピークはメタクリル酸メチルのカルボン酸エステル（−ＣＯＯＣＨ_３）の水素、１２．４ｐｐｍのピークはメタクリル酸のカルボン酸の水素と、スペクトルの積分比から共重合体組成を決定することができる。
【００３９】
また、本発明に使用される（Ａ）熱可塑性共重合体中に含有される（ｉｉｉ）不飽和カルボン酸単位量は０〜１０重量％、より好ましくは０〜５重量％である。（ｉｉｉ）不飽和カルボン酸単位量が１０重量％を超える場合には、無色透明性、滞留安定性が低下する傾向がある。また（ｉｉ）不飽和カルボン酸アルキルエステル単位量は好ましくは５０〜９５重量％、より好ましくは５５〜９０重量％、共重合可能な他のビニル系単量体は好ましくは０〜３５重量％である。
【００４０】
また、本発明に用いられる（Ａ）熱可塑性共重合体の極限粘度に特に制限はないが、ウベローデ型粘度計でジメチルホルムアミド溶液、３０℃で測定した極限粘度が０．１〜０．７ｄｌ／ｇであることが好ましく、より好ましくは０．３〜０．６ｄｌ／ｇである。
【００４１】
かくして得られる（Ａ）熱可塑性共重合体は、以下の特性を有する。すなわち、２８０ｎｍの吸光度（ここで、吸光度は、厚さ１００μｍのフィルムを用いて、分光光度計で測定した値）が０．５以下、特に好ましい態様においては０．４５以下の熱可塑性重合体が得られることを見出した。下限については、通常、０．２程度のものを得ることができる。
【００４２】
上記特定範囲の吸光度特性を満たすことにより、黄色度（Ｙｅｌｌｏｗｎｅｓｓ　Ｉｎｄｅｘ）の値が約６以下、特に好ましい態様においては５以下と着色が極めて抑制されることを見いだした。
【００４３】
上記（Ａ）熱可塑性共重合体は、ガラス転移温度が１３０℃以上と優れた耐熱性を有し、過酷な気象条件下で使用されるシートとして、実用耐熱性の面で好ましい。また、好ましい態様においては１４０℃以上、特に好ましい態様においては１５０℃以上の極めて優れた耐熱性を有する。（Ａ）熱可塑性共重合体のガラス転移温度は、（ｉ）〜（ｉｖ）の共重合組成に依存するが、主としてグルタル酸無水物単位の含有量に左右され、これが多いほどガラス転移温度が高くなる傾向にある。本発明においては、通常、ガラス転移温度１７０℃以下程度のものが好ましい。なお、ここでいうガラス転移温度とは、示差走査熱量計（Ｐｅｒｋｉｎ　Ｅｌｍｅｒ社製ＤＳＣ−７型）を用いて昇温速度２０℃／分で測定したガラス転移温度である。
【００４４】
本発明のシートの製造方法には、公知の方法を使用することができる。すなわち、インフレーション法、Ｔ−ダイ法、カレンダー法、切削法、キャスト法、エマルション法、ホットプレス法等の製造法が使用できるが、好ましくは、インフレーション法、Ｔ−ダイ法、キャスト法、ホットプレス法が使用できる。インフレーション法やＴ−ダイ法による製造法の場合、単軸あるいは二軸押出スクリューのついたエクストルーダ型溶融押出装置等が使用できる。本発明のシートを製造するための溶融押出温度は、グルタル酸無水物単位を含有する共重合体の種類にも依るが、好ましくは１５０〜３５０℃、より好ましくは２００〜３００℃である。また、溶融押出装置を使用し溶融混練する場合、着色抑制の観点から、ベントを使用し減圧下での溶融混練あるいは窒素気流下での溶融混練を行うことが好ましい。また、キャスト法により本発明のシートを製造する場合、テトラヒドロフラン、アセトン、ジメチルホルムアミド、ジメチルスルホキシド、Ｎ−メチルピロリドン等の溶剤が使用可能であり、好ましくはテトラヒドロフラン、アセトンあるいはＮ−メチルピロリドン等が使用できる。本発明のシートは、（Ａ）熱可塑性共重合体を前記の１種以上の溶剤に溶かし、その溶液を大型ドラム上あるいは大型金属バンド上に流し出し、溶剤を蒸発除去する乾式法あるいは溶液を凝固液で固化する湿式法等を用いることにより製造できる。また、ホットプレス法により本発明のシートを製造する場合、グルタル酸無水物単位を含有する共重合体の種類にも依るが、好ましいプレス温度は１５０〜３５０℃、より好ましくは２００〜３００℃である。
【００４５】
また、本発明のシートの厚みについては、特に制限はないが、０．１〜２０ｍｍの範囲内にあることが好ましい。
【００４６】
また、本発明は、（Ａ）熱可塑性共重合体から構成されるシートを少なくとも一層に含む積層シートであってもよい。なかでも表面層の少なくとも一方が、上記（Ａ）熱可塑性共重合体からなる層である積層シートとすることが好ましく、かかる積層シートは２層であっても３層以上であってもよく、（Ｂ）基材を有し、表面層の少なくとも一方が上記（Ａ）熱可塑性共重合体からなる層を有していることが本発明で用いる熱可塑性共重合体が有する優れた特性をより一層発揮させ得る点で好ましい。
【００４７】
本発明の積層シートにおける基材とは、（Ａ）熱可塑性共重合体を積層することが可能であれば特に制限されず、基材自体も単層または積層シートであってもよい。基材を構成する材料として好ましくは、熱可塑性樹脂、紙、布、ガラス、アルミ箔、銅箔、セロファン、不織布等であり、最も好ましくは、本発明の効果である耐擦傷性、耐油性、耐薬品性、耐候性の向上効果が顕著である熱可塑性樹脂である。
【００４８】
本発明の積層シートを製造する場合、公知の方法を使用することができる。すなわち、（Ｂ）基材の両面あるいは片面に、（Ａ）熱可塑性共重合体のシートをラミネートする方法や、（Ｂ）基材が熱可塑性樹脂である場合、（Ａ）熱可塑性共重合体と熱可塑性樹脂とを共押出成形する方法等が使用できる。ラミネート法により本発明の積層シートを得る場合、公知の技術が使用できる。すなわち、ウェットラミネート、ドライラミネート、ホットメルトラミネート等が使用できる。ウェットラミネートの場合、水性接着剤を（Ａ）熱可塑性共重合体シートあるいは（Ｂ）基材に塗布し、接着剤が乾かない内に、直ちに（Ｂ）基材あるいは（Ａ）熱可塑性共重合体シートを貼り合わせ、乾燥して積層シートとする。また、ドライラミネートの場合、（Ａ）熱可塑性共重合体シートあるいは（Ｂ）基材に水性あるいは有機溶剤に熔解させた接着剤をグラビアコートあるいはリバースコートで均一に塗布し、乾燥オーブン中で溶剤分を蒸発・乾燥させ、乾燥粘着状態になった接着剤層面に貼り合わせるべき（Ｂ）基材あるいは（Ａ）熱可塑性共重合体シートを重ね、通常４０〜１００℃に加熱した金属ロールとゴムロールとで圧着ラミネートし、冷却金属ロールを通過させ積層シートとする。ホットメルトラミネートの場合、ホットメルト接着剤を使用し、押出方式やグラビアロールコーティング、ロールコーティング等の方法を使用し、積層シートとする。
【００４９】
本発明の積層シートの製造において、（Ｂ）基材が熱可塑性樹脂である場合、工程数が少ないこと、接着剤・溶剤が不要であること、極薄の層を形成可能であること等から共押出成形する方法が好ましく使用される。また、共押出成形の中でも、Ｔ−ダイ法、インフレーション法等が好ましく使用でき、より好ましくは、膜厚の制御が容易なＴ−ダイ法による共押出が使用できる。Ｔ−ダイ共押出成形法は、２種以上の樹脂を別々の押出機から同時に押出、Ｔ−ダイの中または外で樹脂を積層し、２層以上の積層シートを１工程で製造する方法である。Ｔ−ダイ共押出成形法により、本発明の積層シートを製造する場合、樹脂の合流方式、合流位置の異なるブラックボックス方式や、マルチマニホールドダイ方式、２−スロットダイ方式等の公知の技術が使用できる。ブラックボックス方式あるいはマルチマニホールドダイ方式では、ブラックボックスあるいはマルチマニホールドダイの中でそれぞれの樹脂を合流・積層し、積層した樹脂をＴ−ダイに導入しシート状に成形した後、成形ロール（ポリッシングロール）を通し積層シートを製造する。また、２−スロットダイ方式では、２−スロットダイに導入されたそれぞれの樹脂を、２−スロットダイの外で合流・積層し、積層した樹脂をＴ−ダイに導入しシート状に成形した後、成形ロール（ポリッシングロール）を通し積層シートを製造する。また、Ｔ−ダイ共押出成形法により、本発明の積層シートを製造する場合、（Ａ）熱可塑性共重合体と熱可塑性樹脂のそれぞれの押出機中での樹脂温度は、それぞれの樹脂が押出できる温度であれば、特に制限されないが、層間の接着性およびヒートシール性を向上させるために、ダイに導入されるそれぞれの樹脂温度に温度差が生じている方が好ましい。積層する際の好ましい温度差としては、ブラックボックスで１０〜２０℃程度、マルチマニホールドダイで３０℃程度、２−スロットダイで５０℃程度である。
【００５０】
本発明の積層シートの製造において、（Ｂ）基材が熱可塑性樹脂である場合、熱可塑性樹脂として使用される樹脂として、特に制限はないが、実用上、透明樹脂である場合には（Ａ）熱可塑性共重合体の優れた透明性を活かして優れた透明積層シートが得られる点で好ましい。ここでいう透明樹脂とは、３ｍｍ厚のシートにおいて、ＪＩＳ−Ｋ−６７１８に従い、東洋精機（株）製直読ヘイズメーターを用いた、２３℃での全光線透過率が７０％以上、好ましくは８０％以上の樹脂をいう。透明樹脂の中でも、好ましくはポリエチレンテレフタレートとシクロヘキサンジメタノールの共重合体（ＰＥＴＧ、ＰＣＴＧ）等の非晶性ポリエステル系樹脂や、ポリカーボネート系樹脂、透明アクリロニトリル−ブタジエン−スチレン共重合体（透明ＡＢＳ樹脂）、ＰＭＭＡ等のアクリル系樹脂、ビニル脂環式炭化水素系重合体等の環状オレフィン系樹脂等が使用されるが、より好ましくは、本発明の積層シートとすることにより、本発明の特徴である耐擦傷性や耐候性の向上効果がより大きくなるポリエチレンテレフタレートとシクロヘキサンジメタノールの共重合体（ＰＥＴＧ、ＰＣＴＧ）等の非晶性ポリエステル系樹脂や、透明アクリロニトリル−ブタジエン−スチレン共重合体（透明ＡＢＳ樹脂）、ポリカーボネート系樹脂等が使用できる。
【００５１】
また、本発明の積層シートのそれぞれの層の厚みについては、特に制限はないが、（Ｂ）基材の層の厚みは、好ましくは０．１〜２０ｍｍ、表面層である（Ａ）熱可塑性共重合体の層の厚みは、好ましくは０．０１〜１０ｍｍである。
【００５２】
かくして得られる本発明の熱可塑性共重合体シートおよび積層シートの熱可塑性共重合体からなる表面層は、好ましい態様において鉛筆硬度として４Ｈ以上の表面硬度、より好ましくは５Ｈ以上の優れた表面硬度が得られる。なお、鉛筆硬度はシート表面または積層シートの（Ａ）熱可塑性共重合体からなる表面層について、ＪＩＳ−Ｋ−５４０１に従い測定されるものである。
【００５３】
さらに、本発明の熱可塑性共重合体シートには、本発明の目的を損なわない範囲でヒンダードフェノール系、ベンゾトリアゾール系、ベンゾフェノン系、ベンゾエート系、およびシアノアクリレート系の紫外線吸収剤および酸化防止剤、高級脂肪酸や酸エステル系および酸アミド系、さらに高級アルコールなどの滑剤および可塑剤、モンタン酸およびその塩、そのエステル、そのハーフエステル、ステアリルアルコール、ステアラミドおよびエチレンワックスなどの離型剤、亜リン酸塩、次亜リン酸塩などの着色防止剤、ハロゲン系難燃剤、リン系やシリコーン系の非ハロゲン系難燃剤、核剤、アミン系、スルホン酸系、ポリエーテル系などの帯電防止剤、顔料などの着色剤などの添加剤を任意に含有させてもよい。ただし、その添加剤保有の色が本発明のシートに悪影響を及ぼさず、かつ透明性が低下しない範囲で添加する必要がある。
【００５４】
これら添加剤の混合方法としては、本発明に使用されるグルタル酸無水物単位を含有する共重合体中に、これら添加剤が十分に分散する方法であれば、特に制限はないが、（Ｃ）原共重合体の製造時、（Ａ）熱可塑性共重合体製造時あるいは本発明の熱可塑性共重合体シート、積層シートの製造時に混合することができるが、好ましくは（Ａ）熱可塑性共重合体製造時あるいは本発明の熱可塑性共重合体シート、積層シートの製造時である。
【００５５】
本発明の熱可塑性共重合体シートおよび積層シートは、製品化のため、公知の技術により、二次加工することが可能である。すなわち、真空成形、圧空成形、圧縮成形、エンボス加工、塗装加工、印刷加工等の方法により、二次加工することが可能である。
【００５６】
本発明の熱可塑性共重合体シートは、無色透明性、耐熱性に優れ、かつ耐擦傷性、耐油性、耐薬品性、ガスバリア性および耐候性が均衡して優れ、また本発明の積層シートは、無色透明性、耐擦傷性、耐油性、耐薬品性、ガスバリア性および耐候性が均衡して優れるため、自動販売機カバーや照明カバー等のカバー類、道路透光板、採光板、道路シェルター、カーポート等の土木建築材料類、バスタブ材料類、ガーニッシュ等の車両外装類、食品や医薬品等の包装材料等に好適に使用することができる。
【００５７】
【実施例】
以下、実施例により本発明の構成、効果をさらに具体的に説明するが、本発明は下記実施例に限定されるものではない。
（Ａ）熱可塑性共重合体の製造
（Ａ−１）：
容量が５リットルで、バッフルおよびファウドラ型撹拌翼を備えたステンレス製オートクレーブに、メタクリル酸メチル／アクリルアミド共重合体系懸濁剤（以下の方法で調整した。メタクリル酸メチル２０重量部、アクリルアミド８０重量部、過硫酸カリウム０．３重量部、イオン交換水１５００重量部を反応器中に仕込み反応器中を窒素ガスで置換しながら７０℃に保った。反応は単量体が完全に、重合体に転化するまで続け、アクリル酸メチルとアクリルアミド共重合体の水溶液として得た。得られた水溶液を懸濁剤として使用した）０．０５部をイオン交換水１６５部に溶解した溶液を供給し、４００ｒｐｍで撹拌し、系内を窒素ガスで置換した。次に、下記混合物質を反応系を撹拌しながら添加し、７０℃に昇温した。内温が７０℃に達した時点を重合開始として、１８０分間保ち、重合を終了した。以降、通常の方法に従い、反応系の冷却、ポリマーの分離、洗浄、乾燥を行い、ビーズ状の（Ｃ−１）原共重合体を得た。この（Ｃ−１）原共重合体の重合率は９８％であった。
【００５８】
メタクリル酸（ＭＡＡ）　　　　　　　　３０重量部
メタクリル酸メチル（ＭＭＡ）　　　　　７０重量部
ｔ−ドデシルメルカプタン　　　　　　　０．６重量部
２，２’−アゾビスイソブチロニトリル　０．４重量部
このビーズ状の（Ｃ−１）原共重合体およびナトリウムメトキシド（（Ｃ−１）原共重合体１００重量部に対し、０．５重量部となる量）を、スクリュウ径３０ｍｍ、Ｌ／Ｄが２５のベント付き同方向回転２軸押出機（池貝鉄工製　ＰＣＭ−３０）のホッパー口より５ｋｇ／ｈで供給して、樹脂温度２５０℃、スクリュウ回転数１００ｒｐｍで溶融押出し、ペレット状のグルタル酸無水物単位を含有する（Ａ−１）熱可塑性共重合体を得た。滞留時間（原料を供給してから、吐出口より吐出されるまでの時間）は、約５分であった。得られた（Ａ−１）熱可塑性共重合体を赤外分光光度計を用いて分析した結果、１８００ｃｍ^−１及び１７６０ｃｍ^−１に吸収ピークが確認され、この（Ａ−１）熱可塑性共重合体中にグルタル酸無水物単位が形成していることを確認した。また、この共重合体を重ジメチルスルホキシドに溶解させ、室温（２３℃）にて^１Ｈ−ＮＭＲを測定し、共重合体組成を決定したところ、メタクリル酸メチル単位７０重量％、グルタル酸無水物単位３０重量％、メタクリル酸単位０重量％であった。また、この（Ａ−１）熱可塑性共重合体の極限粘度は０．４６ｄｌ／ｇであった。
【００５９】
（Ａ−２）：
単量体仕込み組成を下記組成に変更した以外は（Ｃ−１）と同様に重合を行い、ビーズ状の（Ｃ−２）原共重合体を得た。この（Ｃ−２）原共重合体の重合率は９８％であった。
【００６０】
メタクリル酸（ＭＡＡ）　　　　　　　　１５重量部
メタクリル酸メチル（ＭＭＡ）　　　　　８５重量部
ｔ−ドデシルメルカプタン　　　　　　　０．６重量部
２，２’−アゾビスイソブチロニトリル　０．４重量部
このビーズ状の（Ｃ−２）原共重合体を、スクリュウ径３０ｍｍ、Ｌ／Ｄが２５のベント付き同方向回転２軸押出機（池貝鉄工製　ＰＣＭ−３０）のホッパー口より５ｋｇ／ｈで供給して、樹脂温度２５０℃、スクリュウ回転数１００ｒｐｍで溶融押出し、ペレット状のグルタル酸無水物単位を含有する（Ａ−２）熱可塑性共重合体を得た。滞留時間（原料を供給してから、吐出口より吐出されるまでの時間）は、約５分であった。得られた（Ａ−２）熱可塑性共重合体を（Ａ−１）と同様の方法で、共重合体組成を決定したところ、メタクリル酸メチル単位８５重量％、グルタル酸無水物単位１０重量％、メタクリル酸単位５重量％であった。また、この（Ａ−２）熱可塑性共重合体の極限粘度は０．４４ｄｌ／ｇであった。
【００６１】
（Ａ−３）：
ｔ−ドデシルメルカプタンを１．２重量部に変更した以外は（Ｃ−１）と同様に重合を行い、ビーズ状の（Ｃ−３）原共重合体を得た。この（Ｃ−３）原共重合体の重合率は９８％であった。
【００６２】
このビーズ状の（Ｃ−３）原共重合体を、スクリュウ径３０ｍｍ、Ｌ／Ｄが２５のベント付き同方向回転２軸押出機（池貝鉄工製　ＰＣＭ−３０）のホッパー口より５ｋｇ／ｈで供給して、樹脂温度２５０℃、スクリュウ回転数１００ｒｐｍで溶融押出し、ペレット状のグルタル酸無水物単位を含有する（Ａ−３）熱可塑性共重合体を得た。滞留時間（原料を供給してから、吐出口より吐出されるまでの時間）は、約５分であった。得られた（Ａ−３）熱可塑性共重合体を（Ａ−１）と同様の方法で、共重合体組成を決定したところ、メタクリル酸メチル単位７０重量％、グルタル酸無水物単位３０重量％であった。また、この（Ａ−３）熱可塑性共重合体の極限粘度は０．４０ｄｌ／ｇであった。
【００６３】
（Ａ−４）：
単量体仕込み組成を下記組成に変更した以外は（Ｃ−１）と同様に重合を行い、ビーズ状の（Ｃ−４）原共重合体を得た。この（Ｃ−４）原共重合体の重合率は９８％であった。
【００６４】
メタクリル酸（ＭＡＡ）　　　　　　　　２５重量部
メタクリル酸メチル（ＭＭＡ）　　　　　６５重量部
スチレン（Ｓｔ）　　　　　　　　　　　１０重量部
ｔ−ドデシルメルカプタン　　　　　　　０．６重量部
２，２’−アゾビスイソブチロニトリル　０．４重量部
このビーズ状の（Ｃ−４）原共重合体を、スクリュウ径３０ｍｍ、Ｌ／Ｄが２５のベント付き同方向回転２軸押出機（池貝鉄工製　ＰＣＭ−３０）のホッパー口より５ｋｇ／ｈで供給して、樹脂温度２５０℃、スクリュウ回転数１００ｒｐｍで溶融押出し、ペレット状のグルタル酸無水物単位を含有する（Ａ−４）熱可塑性共重合体を得た。滞留時間（原料を供給してから、吐出口より吐出されるまでの時間）は、約５分であった。得られた（Ａ−４）熱可塑性共重合体を（Ａ−１）と同様の方法で、共重合体組成を決定したところ、メタクリル酸メチル単位６０重量％、グルタル酸無水物単位２０重量％、メタクリル酸単位５重量％、スチレン単位１５重量％であった。また、この（Ａ−４）熱可塑性共重合体の極限粘度は０．４５ｄｌ／ｇであった。
【００６５】
（Ａ−５）：
特開平２−２３９９３１の実施例に記載の方法を参考にし（Ｃ−５）原共重合体の製造を行った。すなわち、メタクリル酸８重量部、メタクリル酸メチル４１重量部、スチレン４１重量部、ｔ−ドデシルメルカプタン０．６重量部およびトルエン３００重量部からなる混合溶液を調整し、環流装置の付いた反応器に供給して重合を行った。重合開始剤として２，２’−アゾビスイソブチロニトリル０．４重量部を用い、重合温度を１２６℃とした。６時間重合後、得られたポリマー溶液を、ヘキサンで再沈・ろ過後、得られたポリマーを粉砕し、７０℃で４８時間真空乾燥し、（Ｃ−５）原共重合体を得た。この（Ｃ−５）原共重合体の重合率は９５％であった。
【００６６】
この（Ｃ−５）原共重合体を、スクリュウ径３０ｍｍ、Ｌ／Ｄが２５のベント付き同方向回転２軸押出機（池貝鉄工製　ＰＣＭ−３０）のホッパー口より５ｋｇ／ｈで供給して、樹脂温度２５０℃、スクリュウ回転数１００ｒｐｍで溶融押出し、ペレット状のグルタル酸無水物単位を含有する（Ａ−５）熱可塑性共重合体を得た。滞留時間（原料を供給してから、吐出口より吐出されるまでの時間）は約５分であった。得られた（Ａ−５）熱可塑性共重合体を（Ａ−１）と同様の方法で、共重合体組成を決定したところ、メタクリル酸メチル単位４４重量％、グルタル酸無水物単位９重量％、メタクリル酸単位２重量％、スチレン単位４５重量％であった。また、この（Ａ−５）熱可塑性共重合体の極限粘度は０．４２ｄｌ／ｇであった。
【００６７】
（Ａ−６）：
特開平９−２７７４６４の実施例に記載の方法を参考にし（Ｃ−６）原共重合体の製造を行った。重合温度・時間を８０℃で１００分、その後９８℃で６０分とした以外は（Ｃ−１）と同様に重合を行い、ビーズ状の（Ｃ−６）原共重合体を得た。この（Ｃ−６）原共重合体の重合率は９８％であった。
【００６８】
このビーズ状の（Ｃ−６）原共重合体およびナトリウムメトキシド（（Ｃ−６）原共重合体１００重量部に対し、０．５重量部となる量）を、スクリュウ径３０ｍｍ、Ｌ／Ｄが２５のベント付き同方向回転２軸押出機（池貝鉄工製　ＰＣＭ−３０）のホッパー口より５ｋｇ／ｈで供給して、樹脂温度２５０℃、スクリュウ回転数１００ｒｐｍで溶融押出し、ペレット状のグルタル酸無水物単位を含有する（Ａ−６）熱可塑性共重合体を得た。滞留時間（原料を供給してから、吐出口より吐出されるまでの時間）は、約５分であった。得られた（Ａ−６）熱可塑性共重合体を（Ａ−１）と同様の方法で、共重合体組成を決定したところ、メタクリル酸メチル単位７０重量％、グルタル酸無水物単位３０重量％、メタクリル酸単位０重量％であった。また、この（Ａ−６）熱可塑性共重合体の極限粘度は０．４６ｄｌ／ｇであった。
【００６９】
（Ｂ−１）：ＰＣである三菱エンジニアリングプラスチック社製“ユーピロン”Ｓ３０００を使用した。
【００７０】
（Ｂ−２）：ＰＭＭＡである住友化学社製“スミペックス”ＬＧを使用した。
【００７１】
実施例１、２、３、比較例１、２、４、５
ペレット状の熱可塑性共重合体（Ａ−１（実施例１）、Ａ−２（実施例２）、Ａ−３（実施例３）、Ａ−４（比較例１）、Ａ−５（比較例４）、Ａ−６（比較例５））およびＢ−１（比較例２）ＰＣである三菱エンジニアリングプラスチック社製“ユーピロン”Ｓ３０００を、東邦プレス社製ホットプレスＴ２−４に供し、プレス温度を２５０℃とし、８０ｍｍ×８０ｍｍ×０．５ｍｍおよび８０ｍｍ×８０ｍｍ×３ｍｍのシートを得、下記方法により評価した。
【００７２】
比較例３
ペレット状の（Ｂ−２）ＰＭＭＡである住友化学社製“スミペックス”ＬＧを、東邦プレス社製ホットプレスＴ２−４に供し、プレス温度を２３０℃とし、８０ｍｍ×８０ｍｍ×０．５ｍｍおよび８０ｍｍ×８０ｍｍ×３ｍｍのシートを得、下記方法により評価した。
（１）透明性
東洋精機（株）製直読ヘイズメーターを用いて、２３℃での全光線透過率（％）、ヘイズ（曇度）（％）を測定し、得られた３ｍｍ厚のシートの透明性を評価した。
【００７３】
（２）耐熱性
得られた熱可塑性共重合体、（Ｂ−１）ＰＣ、（Ｂ−２）ＰＭＭＡのペレットを、示差走査熱量計（Ｐｅｒｋｉｎ　Ｅｌｍｅｒ社製ＤＳＣ−７型）を用い、窒素雰囲気下、２０℃／ｍｉｎの昇温速度でガラス転移温度（Ｔｇ）を測定した。
【００７４】
（３）表面硬度
得られた３ｍｍ厚シートの鉛筆硬度を、太佑機材（株）社製鉛筆引かき試験機に供しＪＩＳ−Ｋ−５４０１に従い測定した。
【００７５】
（４）耐油性
得られた３ｍｍ厚シートをギアー油（（株）ジャパンエナジー製ＧＥＡＲ５）に浸し、４０℃で２４時間浸漬処理後の全光線透過率を上記（１）項記載の方法で測定し、処理前後での全光線透過率の保持率（（処理後の全光線透過率（％）／処理後の全光線透過率（％））×１００（％））を算出し、耐油性の指標とした。
【００７６】
（５）耐薬品性
得られた３ｍｍ厚シートを（イ）エタノールあるいは（ロ）トルエンに浸し、４０℃で２４時間浸漬処理後の全光線透過率を上記（１）項記載の方法で測定し、処理前後での全光線透過率の保持率（（処理後の全光線透過率（％）／処理後の全光線透過率（％））×１００（％））を算出し、耐薬品性の指標とした。
【００７７】
（６）耐候性
得られた３ｍｍ厚シートをＪＩＳ　Ｄ０２０５に規定されたサンシャインウェザーメーターで１０００時間暴露処理後の全光線透過率を上記（１）項記載の方法で測定し、処理前後での全光線透過率の保持率（（処理後の全光線透過率（％）／処理後の全光線透過率（％））×１００（％））を算出し、耐候性の指標とした。
【００７８】
（７）吸光度
得られた熱可塑性共重合体ペレット、（Ｂ−１）ＰＣ、（Ｂ−２）ＰＭＭＡのペレットを使用し、２０重量％のテトラヒドロフラン溶液を調製し、この溶液を使用し流延法により１００μｍフィルムを作成した。島津製作所製紫外可視分光光度計（ＵＶ−１６００ＰＣ）を用いて、該フィルムの２８０ｎｍ波長における吸光度を測定した。
【００７９】
（８）黄色度（ΔＹＩ値）
得られた３ｍｍ厚シートをＪＩＳ−Ｋ−７１０３に従い、ＳＭカラーコンピューター（スガ試験機社製）を用いて、透過法によりΔＹＩ値を測定した。
【００８０】
（９）ガスバリア性（酸素、水蒸気）
得られた０．５ｍｍ厚シートを、ＧＴＲテック社製ＧＴＲ−３０ＸＡＴＫガス透過性試験機に供し、ＪＩＳ−Ｋ−７１２６　Ａ法（差圧法）に従って、３５℃、ｄｒｙガス（酸素）および４０℃、１００％ＲＨ（水蒸気）で酸素透過係数および水蒸気透過係数を測定した。なお、透過係数が小さいほど、ガスバリア性に優れることを意味する。
【００８１】
【表１】

【００８２】
実施例１〜３、比較例１〜３の比較により、本発明のシートに使用される特定の共重合体は、従来材料であるＰＣやＰＭＭＡに対して、良好な透明性、耐熱性を有し、耐擦傷性、耐油性、耐薬品性、ガスバリア性および耐候性が均衡して優れることがわかる。
【００８３】
また、実施例１〜３、比較例４〜５の比較により、本発明のシートに使用される特定の共重合体は、重合温度を９５℃以下とすることにより、無色透明性が大きく改良されることがわかる。
【００８４】
一方、比較例１に示した共重合体は、良好な無色透明性、耐熱性を有するものの、耐擦傷性、耐油性、耐候性に劣り十分なシートとしての性能を発現しないことがわかる。
【００８５】
［実施例４］
（Ｂ−１）ＰＣである三菱エンジニアリングプラスチック社製　“ユーピロン”Ｓ３０００を、４０ｍｍ直径のベント付き単軸押出機に供し、２７０℃で２０ｋｇ／ｈの速度で押出すとともに、（Ａ−２）熱可塑性共重合体を、２２ｍｍ直径のベント付き単軸押出機に供し、２５０℃で２ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、二層積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ａ−２）熱可塑性共重合体層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを、８０ｍｍ×８０ｍｍ×０．５ｍｍおよび８０ｍｍ×８０ｍｍ×３ｍｍに切削し、下記（１０）〜（１４）の方法により評価した。
【００８６】
［実施例５］
（Ｂ−３）透明ＡＢＳ樹脂である東レ社製　“トヨラック”９２０を４０ｍｍ直径のベント付き単軸押出機に供し、２３０℃で２０ｋｇ／ｈの速度で押出すとともに、（Ａ−２）熱可塑性共重合体を、２２ｍｍ直径のベント付き単軸押出機に供し、２５０℃で２ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ａ−２）熱可塑性共重合体層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを、実施例４と同様に評価した。
【００８７】
［実施例６］
（Ｂ−４）ＰＥＴＧであるイーストマンケミカル社製“イースター”ＧＮ００２を４０ｍｍ直径のベント付き単軸押出機に供し、２３０℃で２０ｋｇ／ｈの速度で押出すとともに、（Ａ−２）熱可塑性共重合体を、２２ｍｍ直径のベント付き単軸押出機に供し、２５０℃で２ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ａ−２）熱可塑性共重合体層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを、実施例４と同様に評価した。
【００８８】
［実施例７］
（Ｂ−２）ＰＭＭＡである住友化学社製“スミペックス”ＬＧを４０ｍｍ直径のベント付き単軸押出機に供し、２３０℃で２０ｋｇ／ｈの速度で押出すとともに、（Ａ−２）熱可塑性共重合体を、２２ｍｍ直径のベント付き単軸押出機に供し、２５０℃で２ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ａ−２）熱可塑性共重合体層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを、実施例４と同様に評価した。
【００８９】
［実施例８］
（Ａ−２）熱可塑性共重合体を４０ｍｍ直径のベント付き単軸押出機に供し、２５０℃で２０ｋｇ／ｈの速度で押出すとともに、（Ｂ−２）ＰＭＭＡである住友化学社製”スミペックス”ＬＧを、２２ｍｍ直径のベント付き単軸押出機に供し、２３０℃で２ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ｂ−２）ＰＭＭＡ層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを、実施例４と同様に評価した。
【００９０】
［実施例９］
（Ａ−２）熱可塑性共重合体を（Ａ−１）熱可塑性共重合体に変更した以外は、実施例４と同様の手法で、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ａ−１）熱可塑性共重合体層の厚みは、それぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを、実施例４と同様に評価した。
【００９１】
［比較例６］
（Ｂ−１）ＰＣである三菱エンジニアリングプラスチック社製　“ユーピロン”Ｓ３０００を、４０ｍｍ直径のベント付き単軸押出機に供し、２７０℃で２０ｋｇ／ｈの速度で押出し、幅２００ｍｍのシート製造用Ｔ−ダイに供しシート状とし、ポリッシングロールに供し、シート厚が０．５ｍｍおよび３ｍｍのシートを得た。得られたシートを、実施例４と同様に評価した。
【００９２】
［比較例７］
（Ｂ−３）透明ＡＢＳ樹脂である東レ社製　“トヨラック”９２０を４０ｍｍ直径のベント付き単軸押出機に供し、２３０℃で２０ｋｇ／ｈの速度で押出し、幅２００ｍｍのシート製造用Ｔ−ダイに供しシート状とし、ポリッシングロールに供し、シート厚が０．５ｍｍおよび３ｍｍのシートを得た。得られたシートを、実施例４と同様に評価した。
【００９３】
［比較例８］
（Ｂ−４）ＰＥＴＧであるイーストマンケミカル社製“イースター”ＧＮ００２を４０ｍｍ直径の単軸押出機に供し、２３０℃で２０ｋｇ／ｈの速度で押出し、幅２００ｍｍのシート製造用Ｔ−ダイに供しシート状とし、ポリッシングロールに供し、シート厚が０．５ｍｍおよび３ｍｍのシートを得た。得られたシートを実施例４と同様に評価した。
【００９４】
［比較例９］
（Ｂ−１）ＰＣである三菱エンジニアリングプラスチック社製　“ユーピロン”Ｓ３０００を、４０ｍｍ直径のベント付き単軸押出機に供し、２７０℃で２０ｋｇ／ｈの速度で押出すとともに、（Ｂ−２）ＰＭＭＡである住友化学社製　スミペックスＬＧを、２２ｍｍ直径のベント付き単軸押出機に供し、２３０℃で２ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、二層積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ｂ−２）ＰＭＭＡ層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを実施例４と同様に評価した。
【００９５】
［比較例１０］
（Ｂ−１）ＰＣである三菱エンジニアリングプラスチック社製　“ユーピロン”Ｓ３０００を、２２ｍｍ直径のベント付き単軸押出機に供し、２５０℃で２ｋｇ／ｈの速度で押出すとともに、（Ｂ−２）ＰＭＭＡである住友化学社製　スミペックスＬＧを、２２ｍｍ直径のベント付き単軸押出機に供し、２３０℃で２ｋｇ／ｈの速度で押出し、さらに（Ｂ−４）ＰＥＴＧであるイーストマンケミカル社製イースターＧＮ００２を４０ｍｍ直径の単軸押出機に供し、２３０℃で２０ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、（Ｂ−２）ＰＭＭＡ、（Ｂ−１）ＰＣ、（Ｂ−４）ＰＥＴＧの順に配し三層積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ｂ−２）ＰＭＭＡ層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）、中間層（Ｂ−１）ＰＣ層の厚みはそれぞれ０．０８ｍｍ（０．５ｍｍ厚積層シート）および０．１ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを、実施例４と同様に評価した。
【００９６】
［比較例１１］
（Ｂ−２）ＰＭＭＡである住友化学社製“スミペックス”ＬＧを４０ｍｍ直径のベント付き単軸押出機に供し、２３０℃で２０ｋｇ／ｈの速度で押出すとともに、（Ａ−５）熱可塑性共重合体を、２２ｍｍ直径のベント付き単軸押出機に供し、２５０℃で２ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ａ−５）熱可塑性共重合体層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを、実施例４と同様に評価した。
【００９７】
［比較例１２］
（Ａ−５）熱可塑性共重合体を、４０ｍｍ直径のベント付き単軸押出機に供し、２５０℃で２０ｋｇ／ｈの速度で押出すとともに、（Ｂ−２）ＰＭＭＡである住友化学社製　スミペックスＬＧを、２２ｍｍ直径のベント付き単軸押出機に供し、２３０℃で２ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、二層積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ｂ−２）ＰＭＭＡ層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを実施例４と同様に評価した。
【００９８】
［比較例１３］
（Ｂ−１）ＰＣである三菱エンジニアリングプラスチック社製　“ユーピロン”Ｓ３０００を、４０ｍｍ直径のベント付き単軸押出機に供し、２７０℃で２０ｋｇ／ｈの速度で押出すとともに、（Ａ−６）熱可塑性共重合体を、２２ｍｍ直径のベント付き単軸押出機に供し、２５０℃で２ｋｇ／ｈの速度で押出し、これら押し出された層状物をマルチマニホールドダイ中で合流させ、幅２００ｍｍのシート製造用Ｔ−ダイに供し、二層積層状とした。その積層状物を、ポリッシングロールに供し、全シート厚が０．５ｍｍおよび３ｍｍの積層シートを得た。得られた積層シートの、表面層（Ａ−６）熱可塑性共重合体層の厚みはそれぞれ０．０５ｍｍ（０．５ｍｍ厚積層シート）および０．０８ｍｍ（３ｍｍ厚積層シート）であった。得られた積層シートを実施例４と同様に評価した。
【００９９】
（１０）表面硬度
得られた３ｍｍ厚のシートおよび積層シートの表面層の鉛筆硬度を、太佑機材（株）社製鉛筆引かき試験機に供しＪＩＳ−Ｋ−５４０１に従い測定した。
【０１００】
（１１）耐油性
得られた３ｍｍ厚のシートおよび積層シートを基材層が下、表面層が上となるように静置し、ギアー油を浸した布をシートにかぶせ表面層のみギアー油に触れる様にし、室温で２４時間処理後の全光線透過率を上記（１）項記載の方法で測定し、処理前後での全光線透過率の保持率（（処理後の全光線透過率（％）／処理後の全光線透過率（％））×１００（％））を算出し、耐油性の指標とした。
【０１０１】
（１２）耐薬品性
得られた３ｍｍ厚のシートおよび積層シートを基材層が下、表面層が上となるように静置し、（イ）エタノールあるいは（ロ）トルエンを浸した布をシートにかぶせ表面層のみ薬液に触れる様にし、室温で２４時間浸漬処理後の全光線透過率を上記（１）項記載の方法で測定し、処理前後での全光線透過率の保持率（（処理後の全光線透過率（％）／処理後の全光線透過率（％））×１００（％））を算出し、耐薬品性の指標とした。
【０１０２】
（１３）耐候性
得られた３ｍｍ厚のシートおよび積層シートを、表面層が暴露される状態に治具に設置し、ＪＩＳ　Ｄ０２０５に規定されたサンシャインウェザーメーターで１０００時間暴露処理後の全光線透過率を上記（１）項記載の方法で測定し、処理前後での全光線透過率の保持率（（処理後の全光線透過率（％）／処理後の全光線透過率（％））×１００（％））を算出し、耐候性の指標とした。
【０１０３】
（１４）黄色度（ΔＹＩ値）
得られた３ｍｍ厚のシートおよび積層シートを、ＪＩＳ−Ｋ−７１０３に従い、ＳＭカラーコンピューター（スガ試験機社製）を用いて、透過法により、シートおよび積層シート全体のΔＹＩ値を測定した。
【０１０４】
（１５）ガスバリア性
得られた０．５ｍｍ厚のシートおよび積層シートを、ＧＴＲテック社製ＧＴＲ−３０ＸＡＴＫガス透過試験機に供し、表面層側からガスを流入するように設置し、ＪＩＳ−Ｋ−７１２６　Ａ法（差圧法）に従って、３５℃、ｄｒｙガス（酸素）および４０℃、１００％ＲＨ（水蒸気）で、酸素透過係数および水蒸気透過係数を測定した。なお、透過係数が小さいほど、ガスバリア性が優れることを意味する。
【０１０５】
【表２】

【０１０６】
実施例４〜６、比較例４〜８の比較により、本発明の積層シートは、従来の熱可塑性樹脂シートあるいは積層シートに対して、耐擦傷性、耐油性、耐薬品性、ガスバリア性および耐候性が均衡して優れることがわかる。
【０１０７】
また、実施例７〜８、比較例１１〜１２の比較により、本発明の積層シートは、無色透明性、耐候性およびガスバリア性が均衡して優れることがわかる。
【０１０８】
また、実施例９、比較例１３の比較により、本発明の積層シートは、重合温度を９５℃以下に規定した熱可塑性共重合体を使用することにより、無色透明性に大きく優れることがわかる。
【０１０９】
【発明の効果】
以上述べたように、本発明によれば、無色透明性、耐熱性に優れ、耐擦傷性、耐油性、耐薬品性、ガスバリア性および耐候性が均衡して優れたシートおよび無色透明性、耐擦傷性、耐油性、耐薬品性、ガスバリア性および耐候性が均衡して優れた積層シートを提供することができる。そのため、本発明の熱可塑性共重合体シートおよび積層シートは、自動販売機カバーや照明カバー等のカバー類、道路透光板、採光板、道路シェルター、カーポート等の土木建築材料類、バスタブ材料類、ガーニッシュ等の車両外装類、食品や医薬品等の包装材料等に好適に使用することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a sheet having excellent colorless transparency, excellent heat resistance, and excellent balance of scratch resistance, oil resistance, chemical resistance, gas barrier property and weather resistance, and colorless transparency, scratch resistance, oil resistance, The present invention relates to a laminated sheet excellent in chemical properties, gas barrier properties and weather resistance.
[0002]
[Prior art]
In recent years, as a transparent resin sheet, polymethyl methacrylate (PMMA), polycarbonate (PC), an amorphous polyester resin, a transparent ABS resin, polyvinyl chloride (PVC), and the like have been developed for various uses. For example, PMMA sheets and PC sheets are used for bathtub materials, road translucent plates, large aquarium materials, lighting covers, automotive window glasses, carports, building roofs, etc. It is mainly used in civil engineering and construction fields, such as passage shelters and road shelters in snowfall areas. In addition, the PC sheet is partially used as a food packaging sheet in a molded container requiring insect repellency and heat resistance. Amorphous polyester-based resins are used not only in the daily necessities field, the medical field, the optical field, and the outdoor field, but also in covers for machines and games. The transparent ABS resin is used for panels and lids of home electric appliances, front covers of OA equipment, housings of TV game machines, and the like.
[0003]
However, although PMMA is excellent in transparency, weather resistance, etc., it is inferior in heat resistance, so it cannot be used for applications requiring heat resistance, such as covers for lighting that emits high temperature such as incandescent lamps, and has poor scratch resistance. Although excellent, a higher surface hardness is required to enable use under severe conditions. In addition, PC is excellent in heat resistance and impact resistance, but is inferior in weather resistance and abrasion resistance.For example, when used for carports and road translucent boards, to improve weather resistance and abrasion resistance, It is necessary to apply a treatment such as laminating an acrylic film on the surface of the PC board or coating the surface with an acrylic resin. Further, although the PC sheet is excellent in transparency, heat resistance, impact resistance, and the like, when it is used for a packaging material for food containers, there is a problem that the PC sheet is inferior in gas barrier properties, moisture resistance, and chemical resistance.
[0004]
As a conventional study, there is a thermoplastic copolymer sheet composed of a copolymer having a specific 6-membered acid anhydride unit and an aromatic vinyl compound unit (for example, see Patent Document 1). Although the copolymer sheet is excellent in transparency, heat resistance and oil resistance, it is not at a practically satisfactory level because it contains an aromatic vinyl compound unit in an amount of 1% by weight or more. There was a problem that the scratch resistance and chemical resistance were poor.
[0005]
As means for improving the scratch resistance and weather resistance of the thermoplastic resin sheet, there is a method of laminating a resin having excellent scratch resistance and weather resistance on the surface of the thermoplastic resin sheet. For example, a PMMA sheet is disposed on both sides of PETG as a means of improving the scratch resistance and weather resistance of a copolymer of a non-crystalline polyester resin, polycyclohexylene terephthalate and polyethylene terephthalate (PETG), and between them. A laminated sheet provided with a PC sheet is disclosed (for example, see Patent Document 2). Certainly, the laminated sheet is excellent in abrasion resistance and weather resistance, but is not a satisfactory level in fields where high abrasion resistance and weather resistance are required, such as carports and road translucent plates. There was a problem.
[0006]
Further, in order to improve the weather resistance of a heat-resistant copolymer resin sheet having 6-membered cyclic anhydride units obtained by heat-treating a copolymer containing unsaturated carboxylic acid units, an acrylic resin sheet is provided on one or both sides. (For example, see Patent Document 3). Certainly, the weather resistance of the heat-resistant copolymer resin sheet is improved by this technique. However, in the invention described in the publication, the copolymer containing unsaturated carboxylic acid units, which is a precursor of the heat-resistant copolymer resin, is polymerized at a high temperature of 126 ° C. The heat-resistant copolymer resin having an acid anhydride unit has a problem that it is greatly colored and the colorless transparency is reduced. Further, in this publication, an acrylic resin sheet is laminated on one or both surfaces of a heat-resistant copolymer resin sheet to form a surface layer, and thus there is a problem that scratch resistance is practically insufficient. Furthermore, the heat-resistant copolymer resin described in the examples of this publication contains styrene units, and the laminated sheet of this publication has improved weather resistance, but has a problem that it is not at a practically satisfactory level. there were.
[0007]
As a technique for improving the gas barrier properties of a PC sheet, there is a method of laminating a copolymer sheet having a specific 6-membered cyclic anhydride unit on one or both sides of the PC sheet (for example, see Patent Document 4). . Certainly, although the laminated sheet is excellent in gas barrier properties, the described copolymer sheet having a specific 6-membered cyclic anhydride unit contains an unsaturated carboxylic acid unit which is a precursor of the copolymer. Since the polymerization temperature of the contained copolymer was high (final polymerization temperature of 98 ° C.), the copolymer was greatly colored, and there was a problem that the colorless transparency was impaired.
[0008]
[Patent Document 1]
JP-A-60-149435 (page 1-2, Example)
[Patent Document 2]
JP-A-8-290532 (page 1-2, Example)
[Patent Document 3]
JP-A-2-23931 (page 1-2, Example)
[Patent Document 4]
JP-A-9-277664 (page 1-2, Example)
[0009]
[Problems to be solved by the invention]
Therefore, the present invention provides a sheet excellent in colorless transparency and heat resistance, and excellent in abrasion resistance, oil resistance, chemical resistance, gas barrier property and weather resistance, and colorless transparency, abrasion resistance, oil resistance Another object of the present invention is to obtain a laminated sheet having excellent chemical resistance, gas barrier properties and weather resistance.
[0010]
[Means for Solving the Problems]
The present inventors have conducted intensive studies to solve the above-mentioned problems, and have as a main component a thermoplastic copolymer composed of an unsaturated carboxylic acid alkyl ester unit and a glutaric anhydride unit and other units as necessary. The present invention has been found that the material has excellent colorless transparency, heat resistance, and excellent scratch resistance, oil resistance, chemical resistance, gas barrier properties and weather resistance, and is useful as a sheet and a laminated sheet. Reached.
[0011]
That is, the present invention
[1] (i) a thermoplastic copolymer comprising a glutaric anhydride unit represented by the following general formula (1) and (ii) an unsaturated carboxylic acid alkyl ester unit, or a thermoplastic copolymer of the above (i) and (ii) A thermoplastic copolymer comprising a unit and (iii) an unsaturated carboxylic acid unit, or a unit of (i) or (ii) or a unit of (i), (ii) or (iii) and (iv) an aromatic ring Is a thermoplastic copolymer composed of other vinyl-based monomer units containing no, and having an absorbance at a wavelength of 280 nm (where the absorbance is measured with a UV-visible spectrophotometer using a film having a thickness of 100 μm). A sheet having a glass transition temperature of 130 ° C. or higher, which is 0.5 or less,
[0012]
Embedded image

[0013]
(In the above formula, R ¹ , R ² Represents the same or different hydrogen atoms or alkyl groups having 1 to 5 carbon atoms)
[2] A monomer mixture containing an unsaturated carboxylic acid alkyl ester monomer and an unsaturated carboxylic acid monomer is polymerized at a temperature of 95 ° C. or lower to obtain (C) a raw copolymer, and then (C) The sheet according to the above [1], wherein the raw copolymer is heated, and (A) a thermoplastic copolymer is obtained by (a) a dealcoholization reaction and / or (b) a dehydration reaction.
[3] (3) The sheet according to the above [1] or [2], wherein the unsaturated carboxylic acid unit has a structure represented by the following general formula (2):
[0014]
Embedded image

[0015]
(However, R ³ Represents hydrogen or an alkyl group having 1 to 5 carbon atoms)
[4] The sheet according to any one of the above [1] to [3], wherein the (ii) unsaturated carboxylic acid alkyl ester unit has a structure represented by the following general formula (3):
[0016]
Embedded image

[0017]
(However, R ⁴ Represents hydrogen or an alkyl group having 1 to 5 carbon atoms; ⁵ Represents an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms or an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms substituted by a hydroxyl group having 1 or more carbon atoms or less and a halogen. )
[5] The sheet according to any one of [1] to [4], wherein the surface hardness is 4H or more in pencil hardness.
[6] a laminated sheet in which at least one of the surface layers is a layer comprising the thermoplastic copolymer (A) according to any one of the above [1] to [4];
[7] The laminated sheet according to the above [6], wherein (A) the surface layer of the thermoplastic copolymer has a surface hardness of 4H or more in pencil hardness.
[8] The laminated sheet according to any of [6] or [7], further comprising (B) a base material, wherein the base material is a thermoplastic resin.
[9] The laminated sheet according to the above [8], wherein the thermoplastic resin is a transparent resin.
[10] The method for producing a laminated sheet according to any one of the above [6] to [9], wherein (A) the thermoplastic copolymer and the thermoplastic resin are coextruded integrally.
Is provided.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the sheet and the laminated sheet of the present invention will be specifically described.
[0019]
The thermoplastic copolymer (A) used in the sheet or laminated sheet of the present invention comprises (i) the following general formula (1)
[0020]
Embedded image

[0021]
(In the above formula, R ¹ , R ² Represents the same or different hydrogen atoms or alkyl groups having 1 to 5 carbon atoms)
A glutaric anhydride unit represented by the following formula, (ii) a thermoplastic copolymer comprising an unsaturated carboxylic acid alkyl ester-based unit, or the units (i) and (ii) and the (iii) unsaturated carboxylic acid unit. A thermoplastic copolymer, or a unit of the above (i) or (ii) or a unit of the above (i), (ii) or (iii) and (iv) another vinyl monomer containing no aromatic ring. It is characterized by being a thermoplastic copolymer, and these can be used alone or in combination of two or more.
[0022]
The method for producing the thermoplastic copolymer (A) used in the present invention is not particularly limited, but can be basically produced by the following method. That is, (i) an unsaturated carboxylic acid alkyl ester monomer and an unsaturated carboxylic acid monomer which give a glutaric anhydride unit represented by the above general formula (1) in a subsequent heating step, and other vinyl-based monomers. When a monomer unit is contained, the monomer unit is copolymerized with a vinyl monomer to give the unit to form a (C) raw copolymer, and then the (C) raw copolymer is prepared in the presence of a suitable catalyst. Alternatively, the thermoplastic copolymer (A) used in the present invention can be produced by heating in the absence of the compound and performing an intramolecular cyclization reaction by (a) dealcoholization and / or (b) dehydration. In this case, typically, (C) elimination of water from the carboxyl group of two units (iii) unsaturated carboxylic acid units by heating the raw copolymer, or (C) The elimination of the alcohol from the iii) unsaturated carboxylic acid unit and one unit of (ii) the unsaturated carboxylic acid alkyl ester unit produces one unit of (i) glutaric anhydride unit.
[0023]
The unsaturated carboxylic acid monomer used at this time is not particularly limited, and any unsaturated carboxylic acid monomer that can be copolymerized with another vinyl compound can be used. As a preferred unsaturated carboxylic acid monomer, the following general formula (4)
[0024]
Embedded image

[0025]
(However, R ³ Represents hydrogen or an alkyl group having 1 to 5 carbon atoms)
And maleic anhydride, and furthermore, a hydrolyzate of maleic anhydride, and the like. Of these, acrylic acid and methacrylic acid are preferable, and methacrylic acid is more preferable, in particular, because heat stability is excellent. These can be used alone or in combination of two or more. The unsaturated carboxylic acid monomer represented by the above general formula (4), when copolymerized, gives (iii) an unsaturated carboxylic acid unit having a structure represented by the above general formula (2).
[0026]
The unsaturated carboxylic acid alkyl ester-based monomer is not particularly limited, but preferred examples include those represented by the following general formula (5).
[0027]
Embedded image

[0028]
(However, R ⁴ Represents hydrogen or an alkyl group having 1 to 5 carbon atoms; ⁵ Represents an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms or an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms substituted by a hydroxyl group having 1 or more carbon atoms or less and a halogen. )
Among them, acrylates and / or methacrylates having an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms or a hydrocarbon group having a substituent are particularly preferred. The unsaturated carboxylic acid alkyl ester monomer represented by the general formula (5) gives, when copolymerized, (ii) an unsaturated carboxylic acid alkyl ester unit having a structure represented by the general formula (3). .
[0029]
Preferred specific examples of the unsaturated carboxylic acid alkyl ester monomer include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, and (meth) acrylate. ) T-butyl acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, chloromethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate , 3-hydroxypropyl (meth) acrylate, 2,3,4,5,6-pentahydroxyhexyl (meth) acrylate, 2,3,4,5-tetrahydroxypentyl (meth) acrylate and the like. Of these, methyl methacrylate is most preferably used. One or more of these can be used.
[0030]
In the production of the thermoplastic copolymer (A) used in the present invention, other vinyl monomers containing no aromatic ring may be used as long as the effects of the present invention are not impaired. Preferred specific examples of other vinyl monomers containing no aromatic ring include acrylonitrile, methacrylonitrile, vinyl cyanide monomers such as ethacrylonitrile, allyl glycidyl ether, maleic anhydride, itaconic anhydride, N-methylmaleimide, N-ethylmaleimide, N-cyclohexylmaleimide, acrylamide, methacrylamide, N-methylacrylamide, butoxymethylacrylamide, N-propylmethacrylamide, aminoethyl acrylate, propylaminoethyl acrylate, dimethylamino methacrylate Ethyl, ethylaminopropyl methacrylate, cyclohexylaminoethyl methacrylate, N-vinyldiethylamine, N-acetylvinylamine, allylamine, methallylamine, N-methylallyl Min, 2-isopropenyl - oxazoline, 2-vinyl - oxazoline, 2-acryloyl - oxazoline, and the like. These can be used alone or in combination of two or more.
[0031]
When a vinyl monomer containing an aromatic ring is copolymerized, scratch resistance, oil resistance, chemical resistance, and weather resistance tend to decrease, so it is preferable not to copolymerize, but the effects of the present invention are not impaired. If it is within the range, it does not matter. Examples of such a vinyl monomer containing an aromatic ring include N-phenylmaleimide and phenylaminoethyl methacrylate. Note that, especially for aromatic vinyl monomers such as styrene, α-methyl styrene, p-glycidyl styrene, styrene-p-glycidyl ether, p-aminostyrene, and 2-styryl-oxazoline, the above-mentioned properties tend to deteriorate. However, it is preferable that the copolymerization is not carried out, but in the case of copolymerization, it is necessary to keep the amount to less than 1% by weight.
[0032]
(C) As the polymerization method of the raw copolymer, a known polymerization method such as bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization, which is basically based on radical polymerization, can be used. From the viewpoint, solution polymerization, bulk polymerization and suspension polymerization are particularly preferred.
[0033]
In order to control the absorbance of the thermoplastic copolymer after the heat treatment within the range of the present invention, (C) the raw copolymer is usually polymerized at a temperature of 95 ° C. or less. In order to further improve the transparency, it is preferable to produce at a polymerization temperature of 90 ° C. or lower, more preferably a polymerization temperature of 85 ° C. or lower, further preferably 80 ° C. or lower, particularly preferably 75 ° C. or lower. , Most preferably 70 ° C or lower. The lower limit of the polymerization temperature is not particularly limited as long as the polymerization proceeds, but is usually 50 ° C. or higher, preferably 60 ° C. or higher from the viewpoint of productivity in consideration of the polymerization rate. For the purpose of improving the polymerization yield or the polymerization rate, it is possible to raise the polymerization temperature in accordance with the progress of the polymerization. In this case, too, the upper limit temperature is usually controlled to 95 ° C. or lower, preferably 90 ° C. or lower. . It is preferable to carry out the polymerization at a relatively low temperature of 75 ° C. or lower. The polymerization time is not particularly limited as long as it is a time sufficient to obtain a required polymerization rate, but is preferably in the range of 60 to 360 minutes, particularly preferably 90 to 180 minutes from the viewpoint of production efficiency.
[0034]
In the present invention, a preferable ratio of the monomer mixture used in the production of the (C) raw copolymer is 15 to 50% by weight of the unsaturated carboxylic acid monomer based on 100% by weight of the monomer mixture. % By weight, more preferably 20 to 45% by weight, and the content of the unsaturated carboxylic acid alkyl ester monomer is preferably 50 to 85% by weight, more preferably 55 to 80% by weight. When other vinyl monomers containing no copolymerizable aromatic ring are used, the preferable ratio thereof is 0 to 35% by weight. However, when an aromatic vinyl compound is copolymerized, the resistance of the present invention is improved. It is necessary to be less than 1% by weight which does not impair the abrasion resistance, oil resistance, chemical resistance and weather resistance.
[0035]
When the amount of the unsaturated carboxylic acid monomer is less than 15% by weight, the amount of the glutaric anhydride unit represented by the above general formula (1) due to heating of the raw copolymer (C) is reduced. , The effect of improving heat resistance tends to decrease. On the other hand, when the amount of the unsaturated carboxylic acid monomer exceeds 50% by weight, a large amount of the unsaturated carboxylic acid unit tends to remain after the cyclization reaction of the (C) raw copolymer by heating, Colorless transparency and retention stability tend to decrease.
[0036]
The (C) raw copolymer in the present invention is heated, and an intramolecular cyclization reaction is performed by (a) dealcoholization and / or (b) dehydration to produce a thermoplastic polymer containing a glutaric anhydride unit. The method is not particularly limited, but is preferably a method of producing through a heated extruder having a vent, or a method of producing in a device capable of being heated and degassed in a nitrogen stream or under vacuum. The temperature for heating and degassing by the above method is not particularly limited as long as it is a temperature at which an intramolecular cyclization reaction by (a) dealcoholization and / or (b) dehydration occurs, but is preferably in the range of 180 to 300 ° C. And particularly preferably in the range of 200 to 280 ° C. In addition, the time for heating and degassing at this time is not particularly limited, and can be appropriately set depending on a desired copolymer composition, but is usually preferably in a range of 1 minute to 60 minutes.
[0037]
Further, in the present invention, (C) adding at least one of an acid, a base and a salt compound as a catalyst for promoting a cyclization reaction to glutaric anhydride when the raw copolymer is heated by the above method or the like. Can be. The addition amount is not particularly limited, and is suitably about 0.01 to 1 part by weight based on 100 parts by weight of the raw copolymer (C). There are no particular restrictions on the type of these acids, bases, and salt compounds. Examples of the acid catalyst include hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, phosphoric acid, phosphorous acid, phenylphosphonic acid, and methyl phosphate. Can be Examples of the basic catalyst include metal hydroxides, amines, imines, alkali metal derivatives, alkoxides, and ammonium hydroxide salts. Further, examples of the salt-based catalyst include metal acetate, metal stearate, and metal carbonate. Among the salt-based catalysts, those exhibiting acidity or basicity when prepared as an aqueous solution are included. These are salt-based catalysts and are distinguished from acid catalysts or basic catalysts. One or more of these catalysts can be added as long as the object of the present invention is not impaired.
[0038]
The content of the (i) glutaric anhydride unit represented by the general formula (1) in the thermoplastic copolymer (A) used in the present invention is determined so that the glass transition temperature is within the range of the present invention. The amount is not particularly limited, but is preferably 5 to 50% by weight, more preferably 10 to 45% by weight, per 100% by weight of the thermoplastic copolymer (A). When the glutaric anhydride unit is less than 5% by weight, the effect of improving heat resistance is small, and sufficient weather resistance tends to be not obtained. In addition, an infrared spectrophotometer can be used for the determination of the glutaric anhydride unit. Glutaric anhydride unit is 1800cm ^-1 And 1760cm ^-1 And can be distinguished from unsaturated carboxylic acid units and unsaturated carboxylic acid alkyl ester units. In addition, for the quantification of each component contained in the copolymer of the present invention, together with the method using the infrared spectrophotometer described above, ¹ A method based on H-NMR can be used. For example, in the case of a copolymer consisting of glutaric anhydride units, methacrylic acid and methyl methacrylate, the peak of 0.5 to 1.5 ppm is assigned to a spectrum, and the peak of 0.5 to 1.5 ppm is methacrylic acid, methyl methacrylate and a glutaric anhydride ring compound. , A peak at 1.6 to 2.1 ppm is a hydrogen of a methylene group in the polymer main chain, and a peak at 3.5 ppm is a carboxylic acid ester of methyl methacrylate (—COOCH). ₃ The hydrogen of 12.4 ppm can determine the copolymer composition from the hydrogen of carboxylic acid of methacrylic acid and the integral ratio of the spectrum.
[0039]
Further, the amount of the unsaturated carboxylic acid unit (iii) contained in the thermoplastic copolymer (A) used in the present invention is 0 to 10% by weight, more preferably 0 to 5% by weight. (Iii) When the amount of the unsaturated carboxylic acid unit exceeds 10% by weight, colorless transparency and retention stability tend to decrease. Also, (ii) the unsaturated carboxylic acid alkyl ester unit amount is preferably 50 to 95% by weight, more preferably 55 to 90% by weight, and the other copolymerizable vinyl monomer is preferably 0 to 35% by weight. is there.
[0040]
Although the intrinsic viscosity of the thermoplastic copolymer (A) used in the present invention is not particularly limited, the intrinsic viscosity measured at 30 ° C. in a dimethylformamide solution with an Ubbelohde viscometer is 0.1 to 0.7 dl /. g, more preferably 0.3 to 0.6 dl / g.
[0041]
The thermoplastic copolymer (A) thus obtained has the following properties. That is, a thermoplastic polymer having an absorbance of 280 nm (where the absorbance is a value measured by a spectrophotometer using a film having a thickness of 100 μm) is 0.5 or less, and in a particularly preferred embodiment, 0.45 or less. It was found that it was obtained. As for the lower limit, usually, a value of about 0.2 can be obtained.
[0042]
By satisfying the above-mentioned specific range of absorbance characteristics, it has been found that coloring is extremely suppressed, with the value of yellowness (Yellowness Index) being about 6 or less, particularly 5 or less in a particularly preferred embodiment.
[0043]
The thermoplastic copolymer (A) has excellent heat resistance such as a glass transition temperature of 130 ° C. or higher, and is preferable in terms of practical heat resistance as a sheet used under severe weather conditions. Further, in a preferred embodiment, it has extremely excellent heat resistance of 140 ° C. or more, and particularly preferably 150 ° C. or more. (A) The glass transition temperature of the thermoplastic copolymer depends on the copolymerization composition of (i) to (iv), but mainly depends on the content of the glutaric anhydride unit. It tends to be higher. In the present invention, usually, those having a glass transition temperature of about 170 ° C. or less are preferable. In addition, the glass transition temperature mentioned here is a glass transition temperature measured at a heating rate of 20 ° C./min using a differential scanning calorimeter (DSK-7 manufactured by Perkin Elmer).
[0044]
Known methods can be used for the method for producing the sheet of the present invention. That is, production methods such as an inflation method, a T-die method, a calendar method, a cutting method, a casting method, an emulsion method, and a hot press method can be used, but preferably, an inflation method, a T-die method, a cast method, and a hot press method are used. Law can be used. In the case of the production method by the inflation method or the T-die method, an extruder-type melt extruder equipped with a single-screw or twin-screw extrusion screw can be used. The melt extrusion temperature for producing the sheet of the present invention depends on the type of the copolymer containing glutaric anhydride units, but is preferably 150 to 350 ° C, more preferably 200 to 300 ° C. When melt kneading is performed using a melt extruder, it is preferable to use a vent to perform melt kneading under reduced pressure or melt kneading under a nitrogen stream from the viewpoint of suppressing coloration. When the sheet of the present invention is manufactured by a casting method, solvents such as tetrahydrofuran, acetone, dimethylformamide, dimethylsulfoxide, and N-methylpyrrolidone can be used.Preferably, tetrahydrofuran, acetone, N-methylpyrrolidone, and the like are used. it can. The sheet of the present invention comprises a dry method of dissolving the thermoplastic copolymer (A) in one or more of the above-mentioned solvents, flowing the solution onto a large drum or a large metal band, and evaporating and removing the solvent. It can be produced by using a wet method of solidifying with a coagulating liquid or the like. When the sheet of the present invention is produced by a hot pressing method, the preferred pressing temperature is 150 to 350 ° C, more preferably 200 to 300 ° C, depending on the type of the copolymer containing glutaric anhydride units. is there.
[0045]
The thickness of the sheet of the present invention is not particularly limited, but is preferably in the range of 0.1 to 20 mm.
[0046]
Further, the present invention may be a laminated sheet including at least one sheet composed of the thermoplastic copolymer (A). Above all, it is preferable that at least one of the surface layers is a laminated sheet that is a layer composed of the thermoplastic copolymer (A), and the laminated sheet may have two layers or three or more layers. It is preferable that the thermoplastic copolymer used in the present invention has (B) a base material and at least one of the surface layers has a layer composed of the thermoplastic copolymer (A). This is preferable in that it can be further exerted.
[0047]
The substrate in the laminated sheet of the present invention is not particularly limited as long as (A) the thermoplastic copolymer can be laminated, and the substrate itself may be a single layer or a laminated sheet. Preferably, the material constituting the base material is a thermoplastic resin, paper, cloth, glass, aluminum foil, copper foil, cellophane, nonwoven fabric, and the like, and most preferably, the abrasion resistance, oil resistance, and the effects of the present invention. It is a thermoplastic resin that has a remarkable effect of improving chemical resistance and weather resistance.
[0048]
When manufacturing the laminated sheet of the present invention, a known method can be used. That is, (A) a method of laminating a sheet of a thermoplastic copolymer on both surfaces or one surface of a base material, or (A) a thermoplastic copolymer when the base material is a thermoplastic resin. And a method of co-extrusion molding with a thermoplastic resin. When the laminated sheet of the present invention is obtained by a laminating method, a known technique can be used. That is, wet lamination, dry lamination, hot melt lamination, and the like can be used. In the case of wet lamination, the aqueous adhesive is applied to the thermoplastic copolymer sheet (A) or the base material (B), and immediately before the adhesive does not dry, the base material (A) or the thermoplastic copolymer (A) is dried. The united sheet is laminated and dried to form a laminated sheet. In the case of dry lamination, an adhesive dissolved in an aqueous or organic solvent is uniformly applied to (A) the thermoplastic copolymer sheet or (B) the substrate by gravure coating or reverse coating, and the solvent is dried in a drying oven. The (B) base material or (A) the thermoplastic copolymer sheet to be bonded is laminated on the adhesive layer surface which has been evaporated and dried to a dry tacky state, and a metal roll and a rubber roll usually heated to 40 to 100 ° C. And laminated by pressing, and passed through a cooling metal roll to form a laminated sheet. In the case of hot melt lamination, a hot melt adhesive is used, and a method such as an extrusion method, gravure roll coating, or roll coating is used to form a laminated sheet.
[0049]
In the production of the laminated sheet of the present invention, when the base material (B) is a thermoplastic resin, the number of steps is small, no adhesive or solvent is required, and an extremely thin layer can be formed. A method of coextrusion is preferably used. In addition, among co-extrusion molding, a T-die method, an inflation method and the like can be preferably used, and more preferably, a co-extrusion by a T-die method in which the film thickness can be easily controlled can be used. The T-die co-extrusion molding method is a method of simultaneously extruding two or more kinds of resins from separate extruders, laminating the resin inside or outside the T-die, and manufacturing a laminated sheet of two or more layers in one step. is there. When the laminated sheet of the present invention is manufactured by the T-die coextrusion molding method, a known technique such as a resin merging method, a black box method having different merging positions, a multi-manifold die method, or a 2-slot die method is used. it can. In the black box method or the multi-manifold die method, respective resins are merged and laminated in a black box or a multi-manifold die, the laminated resin is introduced into a T-die, formed into a sheet, and then formed into a forming roll (polishing roll). ) To produce a laminated sheet. In the 2-slot die method, the respective resins introduced into the 2-slot die are joined and laminated outside the 2-slot die, and the laminated resin is introduced into a T-die and formed into a sheet. Then, a laminated sheet is manufactured through a forming roll (polishing roll). When the laminated sheet of the present invention is manufactured by the T-die coextrusion molding method, the resin temperature of each of the thermoplastic copolymer and the thermoplastic resin in the respective extruders is determined as follows. The temperature is not particularly limited as long as it is a temperature that can be achieved, but it is preferable that a temperature difference is generated between the respective resins introduced into the die in order to improve the adhesion between layers and the heat sealing property. Preferred temperature differences for lamination are about 10 to 20 ° C. for a black box, about 30 ° C. for a multi-manifold die, and about 50 ° C. for a two-slot die.
[0050]
In the production of the laminated sheet of the present invention, when the base material (B) is a thermoplastic resin, the resin used as the thermoplastic resin is not particularly limited. This is preferable because an excellent transparent laminated sheet can be obtained by utilizing the excellent transparency of the thermoplastic copolymer. The term “transparent resin” used herein refers to a sheet having a thickness of 3 mm and a total light transmittance at 23 ° C. of 70% or more, preferably 80%, using a direct-reading haze meter manufactured by Toyo Seiki Co., Ltd. in accordance with JIS-K-6718. % Resin. Among the transparent resins, preferably, an amorphous polyester resin such as a copolymer of polyethylene terephthalate and cyclohexanedimethanol (PETG, PCTG), a polycarbonate resin, a transparent acrylonitrile-butadiene-styrene copolymer (transparent ABS resin) An acrylic resin such as PMMA, a cyclic olefin resin such as a vinyl alicyclic hydrocarbon-based polymer, or the like is used. More preferably, the laminated sheet of the present invention is a feature of the present invention. Amorphous polyester resins such as polyethylene terephthalate and cyclohexane dimethanol copolymers (PETG, PCTG) and transparent acrylonitrile-butadiene-styrene copolymers (transparent ABS), which have a greater effect of improving scratch resistance and weather resistance Resin), polycarbonate resin, etc. It can be.
[0051]
The thickness of each layer of the laminated sheet of the present invention is not particularly limited, but the thickness of the (B) base material layer is preferably 0.1 to 20 mm, and the surface layer is (A) thermoplastic. The thickness of the copolymer layer is preferably 0.01 to 10 mm.
[0052]
The thus obtained thermoplastic copolymer sheet of the present invention and the surface layer composed of the thermoplastic copolymer of the laminated sheet have a surface hardness of 4H or more as a pencil hardness in a preferred embodiment, and more preferably an excellent surface hardness of 5H or more. can get. The pencil hardness is measured in accordance with JIS-K-5401 for the sheet surface or the surface layer of the laminated sheet made of the thermoplastic copolymer (A).
[0053]
Further, the thermoplastic copolymer sheet of the present invention includes a hindered phenol-based, benzotriazole-based, benzophenone-based, benzoate-based, and cyanoacrylate-based ultraviolet absorber and antioxidant within a range not to impair the purpose of the present invention. Lubricants and plasticizers such as higher fatty acids, acid esters and acid amides, higher alcohols and the like, release agents such as montanic acid and salts thereof, esters thereof, half esters thereof, stearyl alcohol, stearamide and ethylene wax, phosphorous acid Colorants such as acid salts and hypophosphites, halogen-based flame retardants, phosphorus-based and silicone-based non-halogen-based flame retardants, nucleating agents, amine-based, sulfonic acid-based, polyether-based antistatic agents, An additive such as a colorant such as a pigment may be optionally contained. However, it is necessary to add the additive within a range in which the color of the additive does not adversely affect the sheet of the present invention and the transparency is not reduced.
[0054]
The method of mixing these additives is not particularly limited as long as these additives are sufficiently dispersed in the copolymer containing glutaric anhydride units used in the present invention. ) It can be mixed at the time of production of the raw copolymer, (A) at the time of production of the thermoplastic copolymer or at the time of production of the thermoplastic copolymer sheet or laminated sheet of the present invention. This is at the time of production of the polymer or at the time of production of the thermoplastic copolymer sheet and the laminated sheet of the present invention.
[0055]
The thermoplastic copolymer sheet and the laminated sheet of the present invention can be subjected to secondary processing by a known technique for commercialization. That is, secondary processing can be performed by a method such as vacuum forming, pressure forming, compression forming, embossing, painting, and printing.
[0056]
The thermoplastic copolymer sheet of the present invention is colorless and transparent, excellent in heat resistance, and excellent in abrasion resistance, oil resistance, chemical resistance, gas barrier properties and weather resistance, and the laminated sheet of the present invention is , Colorless and transparent, abrasion resistance, oil resistance, chemical resistance, gas barrier properties and weather resistance are balanced and excellent, so covers such as vending machine covers and lighting covers, road translucent boards, daylighting boards, road shelters It can be suitably used for civil engineering construction materials such as carports, bathtub materials, vehicle exterior materials such as garnishes, packaging materials for foods and pharmaceuticals, and the like.
[0057]
【Example】
Hereinafter, the configuration and effects of the present invention will be described more specifically with reference to Examples, but the present invention is not limited to the following Examples.
(A) Production of thermoplastic copolymer
(A-1):
In a stainless steel autoclave having a capacity of 5 liters and equipped with a baffle and a Faudra type stirring blade, a methyl methacrylate / acrylamide copolymer suspension (prepared by the following method: 20 parts by weight of methyl methacrylate, 80 parts by weight of acrylamide) Then, 0.3 parts by weight of potassium persulfate and 1500 parts by weight of ion-exchanged water were charged into a reactor, and the temperature of the reactor was maintained at 70 ° C. while replacing the reactor with nitrogen gas. The reaction was continued until the conversion, and an aqueous solution of methyl acrylate and acrylamide copolymer was obtained. The obtained aqueous solution was used as a suspending agent. A solution obtained by dissolving 0.05 part in 165 parts of ion-exchanged water was supplied, and 400 rpm was supplied. And the system was purged with nitrogen gas. Next, the following mixture was added while stirring the reaction system, and the temperature was raised to 70 ° C. The time when the internal temperature reached 70 ° C. was defined as the start of polymerization, and was maintained for 180 minutes to complete the polymerization. Thereafter, the reaction system was cooled, the polymer was separated, washed, and dried according to a usual method to obtain a bead-like (C-1) raw copolymer. The polymerization rate of this (C-1) raw copolymer was 98%.
[0058]
Methacrylic acid (MAA) 30 parts by weight
70 parts by weight of methyl methacrylate (MMA)
0.6 parts by weight of t-dodecyl mercaptan
0.4 parts by weight of 2,2'-azobisisobutyronitrile
The bead-shaped (C-1) raw copolymer and sodium methoxide (an amount of 0.5 parts by weight with respect to 100 parts by weight of the (C-1) raw copolymer) were mixed with a screw diameter of 30 mm, L / D is supplied at 5 kg / h from a hopper port of a co-rotating twin-screw extruder (PCM-30 manufactured by Ikegai Tekko Co., Ltd.) with 25 vents, melt-extruded at a resin temperature of 250 ° C. and a screw rotation speed of 100 rpm, and pelletized glutar. (A-1) a thermoplastic copolymer containing an acid anhydride unit was obtained. The residence time (time from supply of the raw material to discharge from the discharge port) was about 5 minutes. The obtained (A-1) thermoplastic copolymer was analyzed using an infrared spectrophotometer. ^-1 And 1760cm ^-1 The absorption peak was confirmed in this, and it was confirmed that a glutaric anhydride unit was formed in this (A-1) thermoplastic copolymer. Further, this copolymer was dissolved in heavy dimethyl sulfoxide, and the solution was dissolved at room temperature (23 ° C.). ¹ H-NMR was measured to determine the copolymer composition. As a result, methyl methacrylate unit was 70% by weight, glutaric anhydride unit was 30% by weight, and methacrylic acid unit was 0% by weight. The intrinsic viscosity of this (A-1) thermoplastic copolymer was 0.46 dl / g.
[0059]
(A-2):
Polymerization was carried out in the same manner as in (C-1) except that the monomer charge composition was changed to the following composition, to obtain a bead-like (C-2) raw copolymer. The polymerization rate of this (C-2) raw copolymer was 98%.
[0060]
Methacrylic acid (MAA) 15 parts by weight
Methyl methacrylate (MMA) 85 parts by weight
0.6 parts by weight of t-dodecyl mercaptan
0.4 parts by weight of 2,2'-azobisisobutyronitrile
This bead-like (C-2) raw copolymer was fed at 5 kg / h from the hopper port of a co-rotating twin-screw extruder (PCM-30 manufactured by Ikegai Iron Works) with a vent having a screw diameter of 30 mm and an L / D of 25 (PCM-30). The mixture was supplied and melt-extruded at a resin temperature of 250 ° C. and a screw rotation speed of 100 rpm to obtain a pellet-like thermoplastic copolymer (A-2) containing glutaric anhydride units. The residence time (time from supply of the raw material to discharge from the discharge port) was about 5 minutes. When the copolymer composition of the obtained thermoplastic copolymer (A-2) was determined by the same method as in (A-1), methyl methacrylate units were 85% by weight and glutaric anhydride units were 10% by weight. And methacrylic acid unit was 5% by weight. The intrinsic viscosity of this (A-2) thermoplastic copolymer was 0.44 dl / g.
[0061]
(A-3):
Polymerization was carried out in the same manner as in (C-1) except that t-dodecyl mercaptan was changed to 1.2 parts by weight to obtain a bead-like (C-3) raw copolymer. The polymerization rate of this (C-3) raw copolymer was 98%.
[0062]
The bead-shaped (C-3) raw copolymer was fed at 5 kg / h from the hopper port of a co-rotating twin-screw extruder (PCM-30 manufactured by Ikegai Iron Works) with a vent having a screw diameter of 30 mm and an L / D of 25. The mixture was supplied and melt-extruded at a resin temperature of 250 ° C. and a screw rotation speed of 100 rpm to obtain a pellet-shaped thermoplastic copolymer (A-3) containing glutaric anhydride units. The residence time (time from supply of the raw material to discharge from the discharge port) was about 5 minutes. When the copolymer composition of the obtained thermoplastic copolymer (A-3) was determined in the same manner as in (A-1), methyl methacrylate unit 70% by weight, glutaric anhydride unit 30% by weight. Met. The intrinsic viscosity of this (A-3) thermoplastic copolymer was 0.40 dl / g.
[0063]
(A-4):
Polymerization was carried out in the same manner as in (C-1) except that the monomer charge composition was changed to the following composition, to obtain a bead-shaped (C-4) raw copolymer. The polymerization rate of this (C-4) raw copolymer was 98%.
[0064]
Methacrylic acid (MAA) 25 parts by weight
Methyl methacrylate (MMA) 65 parts by weight
Styrene (St) 10 parts by weight
0.6 parts by weight of t-dodecyl mercaptan
0.4 parts by weight of 2,2'-azobisisobutyronitrile
This bead-shaped (C-4) raw copolymer was fed at 5 kg / h from the hopper port of a co-rotating twin-screw extruder (PCM-30 manufactured by Ikegai Iron Works) with a vent having a screw diameter of 30 mm and an L / D of 25. The mixture was supplied and melt-extruded at a resin temperature of 250 ° C. and a screw rotation speed of 100 rpm to obtain a thermoplastic copolymer (A-4) containing pelletized glutaric anhydride units. The residence time (time from supply of the raw material to discharge from the discharge port) was about 5 minutes. When the copolymer composition of the obtained thermoplastic copolymer (A-4) was determined in the same manner as in (A-1), methyl methacrylate unit 60% by weight, glutaric anhydride unit 20% by weight. And methacrylic acid units were 5% by weight and styrene units were 15% by weight. The intrinsic viscosity of this (A-4) thermoplastic copolymer was 0.45 dl / g.
[0065]
(A-5):
With reference to the method described in the examples of JP-A-2-239931, a (C-5) raw copolymer was produced. That is, a mixed solution consisting of 8 parts by weight of methacrylic acid, 41 parts by weight of methyl methacrylate, 41 parts by weight of styrene, 0.6 parts by weight of t-dodecylmercaptan and 300 parts by weight of toluene was prepared, and placed in a reactor equipped with a reflux device. The polymerization was carried out by feeding. 0.4 parts by weight of 2,2′-azobisisobutyronitrile was used as a polymerization initiator, and the polymerization temperature was set to 126 ° C. After polymerization for 6 hours, the obtained polymer solution was reprecipitated with hexane and filtered, and then the obtained polymer was pulverized and vacuum-dried at 70 ° C for 48 hours to obtain a (C-5) raw copolymer. The polymerization rate of this (C-5) raw copolymer was 95%.
[0066]
The (C-5) raw copolymer was supplied at a rate of 5 kg / h from a hopper port of a co-rotating twin-screw extruder (PCM-30 manufactured by Ikegai Iron Works) with a screw diameter of 30 mm and an L / D of 25 with a screw diameter of 25 mm. The resin was melt-extruded at a resin temperature of 250 ° C. and a screw rotation speed of 100 rpm to obtain a thermoplastic copolymer (A-5) containing glutaric anhydride units in the form of pellets. The residence time (time from supply of the raw material to discharge from the discharge port) was about 5 minutes. When the copolymer composition of the obtained thermoplastic copolymer (A-5) was determined in the same manner as in (A-1), methyl methacrylate unit was 44% by weight and glutaric anhydride unit was 9% by weight. And methacrylic acid units were 2% by weight and styrene units were 45% by weight. Further, the intrinsic viscosity of this (A-5) thermoplastic copolymer was 0.42 dl / g.
[0067]
(A-6):
The (C-6) raw copolymer was produced with reference to the method described in the examples of JP-A-9-277664. Polymerization was carried out in the same manner as in (C-1) except that the polymerization temperature and time were changed to 80 ° C. for 100 minutes, and then to 98 ° C. for 60 minutes, to obtain a bead-like (C-6) raw copolymer. The polymerization rate of this (C-6) raw copolymer was 98%.
[0068]
The bead-shaped (C-6) raw copolymer and sodium methoxide (an amount of 0.5 parts by weight based on 100 parts by weight of the (C-6) raw copolymer) were mixed with a screw diameter of 30 mm, L / D is supplied at 5 kg / h from a hopper port of a co-rotating twin-screw extruder with 25 vents (PCM-30 manufactured by Ikegai Iron Works), melt-extruded at a resin temperature of 250 ° C. and a screw rotation speed of 100 rpm, and pelletized glutar. (A-6) a thermoplastic copolymer containing an acid anhydride unit was obtained. The residence time (time from supply of the raw material to discharge from the discharge port) was about 5 minutes. When the copolymer composition of the obtained thermoplastic copolymer (A-6) was determined by the same method as in (A-1), methyl methacrylate unit was 70% by weight and glutaric anhydride unit was 30% by weight. And methacrylic acid unit was 0% by weight. The intrinsic viscosity of this (A-6) thermoplastic copolymer was 0.46 dl / g.
[0069]
(B-1): PC "Iupilon" S3000 manufactured by Mitsubishi Engineering-Plastics Corporation was used.
[0070]
(B-2): PMMA “SUMIPEX” LG manufactured by Sumitomo Chemical Co., Ltd. was used.
[0071]
Examples 1, 2, 3, Comparative Examples 1, 2, 4, 5
Pellets of thermoplastic copolymer (A-1 (Example 1), A-2 (Example 2), A-3 (Example 3), A-4 (Comparative Example 1), A-5 (Comparative Example 4) A-6 (Comparative Example 5)) and B-1 (Comparative Example 2) PC "Mupilon" S3000 manufactured by Mitsubishi Engineering-Plastics Co., Ltd. was subjected to a hot press T2-4 manufactured by Toho Press Co., Ltd. Was set to 250 ° C., and sheets of 80 mm × 80 mm × 0.5 mm and 80 mm × 80 mm × 3 mm were obtained and evaluated by the following method.
[0072]
Comparative Example 3
The pellet-form (B-2) PMMA "SUMIPEX" LG manufactured by Sumitomo Chemical Co., Ltd. was subjected to a hot press T2-4 manufactured by Toho Press Co., at a press temperature of 230 ° C., and 80 mm × 80 mm × 0.5 mm and 80 mm × An 80 mm × 3 mm sheet was obtained and evaluated by the following method.
(1) Transparency
The total light transmittance (%) and haze (cloudiness) (%) at 23 ° C. were measured using a direct-read haze meter manufactured by Toyo Seiki Co., Ltd., and the transparency of the obtained 3 mm-thick sheet was evaluated. .
[0073]
(2) Heat resistance
The obtained thermoplastic copolymer, (B-1) PC, and (B-2) PMMA pellets were subjected to a differential scanning calorimeter (DSK-7 manufactured by Perkin Elmer) at 20 ° C. The glass transition temperature (Tg) was measured at a heating rate of min.
[0074]
(3) Surface hardness
The pencil hardness of the obtained 3 mm thick sheet was measured with a pencil scratch tester manufactured by Taiyo Kiki Co., Ltd. in accordance with JIS-K-5401.
[0075]
(4) Oil resistance
The obtained 3 mm thick sheet is immersed in gear oil (GEAR5 manufactured by Japan Energy Co., Ltd.), and the total light transmittance after immersion treatment at 40 ° C. for 24 hours is measured by the method described in the above (1). Was calculated ((total light transmittance after treatment (%) / total light transmittance after treatment (%)) × 100 (%)) as an index of oil resistance.
[0076]
(5) Chemical resistance
The obtained 3 mm thick sheet is immersed in (a) ethanol or (b) toluene, and the total light transmittance after immersion treatment at 40 ° C. for 24 hours is measured by the method described in the above (1). The retention of light transmittance ((total light transmittance after treatment (%) / total light transmittance after treatment (%)) × 100 (%)) was calculated and used as an index of chemical resistance.
[0077]
(6) Weather resistance
The total light transmittance of the obtained 3 mm-thick sheet after exposure treatment for 1000 hours with a sunshine weather meter specified in JIS D0205 is measured by the method described in the above item (1), and the total light transmittance before and after the treatment is maintained. The ratio ((total light transmittance after treatment (%) / total light transmittance after treatment (%)) × 100 (%)) was calculated and used as an index of weather resistance.
[0078]
(7) Absorbance
Using the obtained thermoplastic copolymer pellets, (B-1) PC, and (B-2) PMMA pellets, a 20% by weight tetrahydrofuran solution is prepared, and a 100 μm film is cast using this solution by a casting method. It was created. The absorbance of the film at a wavelength of 280 nm was measured using an ultraviolet-visible spectrophotometer (UV-1600PC) manufactured by Shimadzu Corporation.
[0079]
(8) Yellowness (ΔYI value)
The ΔYI value of the obtained 3 mm thick sheet was measured by a transmission method using an SM color computer (manufactured by Suga Test Instruments Co., Ltd.) according to JIS-K-7103.
[0080]
(9) Gas barrier properties (oxygen, water vapor)
The obtained 0.5 mm-thick sheet was subjected to a GTR-30XATK gas permeability tester manufactured by GTR Tech Co., Ltd., and according to JIS-K-7126 A method (differential pressure method), 35 ° C, dry gas (oxygen) and 40 ° C, The oxygen transmission coefficient and the water vapor transmission coefficient were measured at 100% RH (water vapor). In addition, it means that gas permeability is excellent, so that a transmission coefficient is small.
[0081]
[Table 1]

[0082]
By comparing Examples 1 to 3 and Comparative Examples 1 to 3, the specific copolymer used for the sheet of the present invention has good transparency and heat resistance with respect to PC and PMMA which are conventional materials. However, it can be seen that the abrasion resistance, oil resistance, chemical resistance, gas barrier property and weather resistance are balanced and excellent.
[0083]
In addition, according to the comparison of Examples 1 to 3 and Comparative Examples 4 and 5, the specific copolymer used in the sheet of the present invention is greatly improved in colorless transparency by setting the polymerization temperature to 95 ° C or lower. You can see that
[0084]
On the other hand, although the copolymer shown in Comparative Example 1 has good colorless transparency and heat resistance, it is inferior in scratch resistance, oil resistance, and weather resistance and does not exhibit sufficient performance as a sheet.
[0085]
[Example 4]
(B-1) PC "Mitsubishi Engineering Plastics" Iupilon S3000 is supplied to a 40 mm diameter vented single screw extruder at 270 ° C. at a rate of 20 kg / h, and (A-2) heat The plastic copolymer is supplied to a 22 mm diameter vented single screw extruder at 250 ° C. and extruded at a rate of 2 kg / h, and the extruded layered materials are combined in a multi-manifold die to produce a 200 mm wide sheet. It was subjected to a T-die to form a two-layer laminate. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (A-2) thermoplastic copolymer layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was cut into 80 mm x 80 mm x 0.5 mm and 80 mm x 80 mm x 3 mm, and evaluated by the following methods (10) to (14).
[0086]
[Example 5]
(B-3) A transparent ABS resin “Toyolac” 920 manufactured by Toray Co., Ltd. was supplied to a 40 mm diameter vented single screw extruder at 230 ° C. and extruded at a rate of 20 kg / h. (A-2) Thermoplastic The copolymer is supplied to a 22 mm diameter vented single screw extruder at 250 ° C. and extruded at a rate of 2 kg / h. The extruded layers are combined in a multi-manifold die to form a 200 mm wide sheet-forming T. -Die and laminated. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (A-2) thermoplastic copolymer layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0087]
[Example 6]
(B-4) PETG “Easter” GN002 manufactured by Eastman Chemical Co., Ltd. was subjected to a 40 mm diameter vented single screw extruder at 230 ° C. and extruded at a rate of 20 kg / h. The copolymer is supplied to a 22 mm diameter vented single screw extruder at 250 ° C. and extruded at a rate of 2 kg / h. The extruded layers are combined in a multi-manifold die to form a 200 mm wide sheet-forming T. -Die and laminated. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (A-2) thermoplastic copolymer layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0088]
[Example 7]
(B-2) PMMA “SUMIPEX” LG manufactured by Sumitomo Chemical Co., Ltd. was supplied to a 40 mm diameter vented single screw extruder at 230 ° C. and extruded at a rate of 20 kg / h. The polymer is supplied to a 22 mm diameter vented single screw extruder at 250 ° C. and extruded at a rate of 2 kg / h, and the extruded layered materials are combined in a multi-manifold die to produce a 200 mm width T-sheet. It was subjected to a die to form a laminate. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (A-2) thermoplastic copolymer layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0089]
Example 8
(A-2) The thermoplastic copolymer is supplied to a 40 mm diameter vented single screw extruder at 250 ° C. and extruded at a rate of 20 kg / h, and (B-2) PMMA, “SUMIPEX manufactured by Sumitomo Chemical Co., Ltd.” The LG was supplied to a 22 mm diameter vented single screw extruder at 230 ° C. and extruded at a rate of 2 kg / h, and the extruded layers were combined in a multi-manifold die to produce a 200 mm width T-sheet. It was subjected to a die to form a laminate. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (B-2) PMMA layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0090]
[Example 9]
(A-2) A laminated sheet having a total sheet thickness of 0.5 mm and 3 mm was obtained in the same manner as in Example 4, except that the thermoplastic copolymer was changed to (A-1) the thermoplastic copolymer. Was. The thickness of the surface layer (A-1) thermoplastic copolymer layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0091]
[Comparative Example 6]
(B-1) PC "Iupilon" S3000 manufactured by Mitsubishi Engineering-Plastics Co., Ltd. is supplied to a 40 mm diameter vented single screw extruder at 270 ° C. and extruded at a speed of 20 kg / h to produce a 200 mm wide sheet T-. The sheet was supplied to a die, formed into a sheet, and supplied to a polishing roll to obtain sheets having a sheet thickness of 0.5 mm and 3 mm. The obtained sheet was evaluated in the same manner as in Example 4.
[0092]
[Comparative Example 7]
(B-3) A transparent ABS resin “Toyolac” 920 manufactured by Toray Co., Ltd. is supplied to a 40 mm diameter vented single screw extruder at 230 ° C. and extruded at a speed of 20 kg / h to produce a 200 mm wide sheet T-die. To obtain a sheet having a sheet thickness of 0.5 mm and 3 mm. The obtained sheet was evaluated in the same manner as in Example 4.
[0093]
[Comparative Example 8]
(B-4) PETG “Easter” GN002 manufactured by Eastman Chemical Company is supplied to a 40 mm diameter single screw extruder, extruded at 230 ° C. at a speed of 20 kg / h, and supplied to a T-die for manufacturing a 200 mm wide sheet. The sheet was formed into a sheet and subjected to a polishing roll to obtain sheets having a sheet thickness of 0.5 mm and 3 mm. The obtained sheet was evaluated in the same manner as in Example 4.
[0094]
[Comparative Example 9]
(B-1) PC "Mitsubishi Engineering Plastics Co., Ltd.""Iupilon" S3000 is supplied to a 40 mm diameter vented single screw extruder at 270 ° C. at a rate of 20 kg / h, and (B-2) PMMA Is supplied to a 22 mm diameter vented single screw extruder at 230 ° C. and extruded at a rate of 2 kg / h, and the extruded layered materials are combined in a multi-manifold die to have a width of 200 mm. To produce a two-layer laminate. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (B-2) PMMA layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0095]
[Comparative Example 10]
(B-1) A PC, "Iupilon" S3000 manufactured by Mitsubishi Engineering-Plastics Co., Ltd. is supplied to a 22 mm diameter vented single screw extruder at 250 ° C. at a rate of 2 kg / h, and (B-2) PMMA Sumipex LG manufactured by Sumitomo Chemical Co., Ltd. is supplied to a 22 mm diameter vented single screw extruder at 230 ° C. and extruded at a rate of 2 kg / h. Further, (B-4) PETG, Easterman GN002 manufactured by Eastman Chemical Co., Ltd. A single-screw extruder having a diameter of 40 mm is used, and extruded at 230 ° C. at a speed of 20 kg / h. -2) PMMA, (B-1) PC, (B-4) PETG were arranged in this order to form a three-layer laminate. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (B-2) PMMA layer of the obtained laminated sheet is 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively, and the intermediate layer (B-1) PC The thicknesses of the layers were 0.08 mm (0.5 mm thick laminated sheet) and 0.1 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0096]
[Comparative Example 11]
(B-2) PMMA “SUMIPEX” LG manufactured by Sumitomo Chemical Co., Ltd. was supplied to a 40 mm diameter vented single screw extruder at 230 ° C. and extruded at a speed of 20 kg / h. The polymer is supplied to a 22 mm diameter vented single screw extruder at 250 ° C. and extruded at a rate of 2 kg / h, and the extruded layered materials are combined in a multi-manifold die to produce a 200 mm width T-sheet. It was subjected to a die to form a laminate. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (A-5) thermoplastic copolymer layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0097]
[Comparative Example 12]
(A-5) The thermoplastic copolymer is supplied to a vented single-screw extruder having a diameter of 40 mm, extruded at a rate of 20 kg / h at 250 ° C., and (B-2) Sumipex manufactured by Sumitomo Chemical Co., Ltd., which is a PMMA. The LG is supplied to a 22 mm diameter vented single screw extruder, extruded at 230 ° C. at a rate of 2 kg / h, and the extruded layers are combined in a multi-manifold die to produce a 200 mm wide sheet-forming T-die. To form a two-layer laminate. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (B-2) PMMA layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0098]
[Comparative Example 13]
(B-1) A "Iupilon" S3000 manufactured by Mitsubishi Engineering-Plastics Co., Ltd., which is a PC, is supplied to a 40 mm diameter vented single screw extruder at 270 [deg.] C. at a rate of 20 kg / h, and (A-6) heat The plastic copolymer is supplied to a 22 mm diameter vented single screw extruder at 250 ° C. and extruded at a rate of 2 kg / h, and the extruded layered materials are combined in a multi-manifold die to produce a 200 mm wide sheet. It was subjected to a T-die to form a two-layer laminate. The laminated product was subjected to a polishing roll to obtain laminated sheets having a total sheet thickness of 0.5 mm and 3 mm. The thickness of the surface layer (A-6) thermoplastic copolymer layer of the obtained laminated sheet was 0.05 mm (0.5 mm thick laminated sheet) and 0.08 mm (3 mm thick laminated sheet), respectively. The obtained laminated sheet was evaluated in the same manner as in Example 4.
[0099]
(10) Surface hardness
The pencil hardness of the surface layer of the obtained 3 mm-thick sheet and the laminated sheet was measured by a pencil scratch tester manufactured by Taiyo Kiki Co., Ltd. in accordance with JIS-K-5401.
[0100]
(11) Oil resistance
The resulting 3 mm-thick sheet and the laminated sheet were allowed to stand still with the base layer facing down and the surface layer facing up. A cloth soaked with gear oil was placed over the sheet so that only the surface layer was in contact with the gear oil, and room temperature was applied. The total light transmittance after the treatment for 24 hours was measured by the method described in the above item (1), and the retention of the total light transmittance before and after the treatment ((total light transmittance after treatment (%) / after treatment) Total light transmittance (%)) x 100 (%)) was calculated and used as an index of oil resistance.
[0101]
(12) Chemical resistance
The resulting 3 mm-thick sheet and the laminated sheet are allowed to stand with the base material layer facing down and the surface layer facing up, and a cloth dipped in (a) ethanol or (b) toluene is placed on the sheet, and only the surface layer has a chemical solution. The total light transmittance after the immersion treatment at room temperature for 24 hours was measured by the method described in the above item (1), and the retention of the total light transmittance before and after the treatment ((total light transmittance after the treatment) (%) / Total light transmittance (%) after treatment) × 100 (%)) was calculated and used as an index of chemical resistance.
[0102]
(13) Weather resistance
The obtained 3 mm-thick sheet and laminated sheet were placed on a jig in a state where the surface layer was exposed, and the total light transmittance after exposure treatment for 1000 hours with a sunshine weather meter specified in JIS D0205 was determined as (1). ), The retention of the total light transmittance before and after the treatment ((total light transmittance after treatment (%) / total light transmittance after treatment (%)) × 100 (%)) Was calculated and used as an index of weather resistance.
[0103]
(14) Yellowness (ΔYI value)
The obtained 3 mm-thick sheet and laminated sheet were measured for ΔYI value of the entire sheet and laminated sheet by a transmission method using an SM color computer (manufactured by Suga Test Instruments Co., Ltd.) according to JIS-K-7103.
[0104]
(15) Gas barrier properties
The obtained 0.5 mm-thick sheet and the laminated sheet are subjected to a GTR-30XATK gas permeation tester manufactured by GTR Tech Co., Ltd., and set so that gas flows in from the surface layer side, and the JIS-K-7126 A method (difference Pressure method), the oxygen transmission coefficient and the water vapor transmission coefficient were measured at 35 ° C., dry gas (oxygen) and 40 ° C., 100% RH (steam). It should be noted that the smaller the transmission coefficient, the better the gas barrier properties.
[0105]
[Table 2]

[0106]
By comparing Examples 4 to 6 and Comparative Examples 4 to 8, the laminated sheet of the present invention is more resistant to abrasion, oil, chemical, gas barrier and weather than a conventional thermoplastic resin sheet or laminated sheet. It can be seen that the properties are balanced and excellent.
[0107]
Further, a comparison of Examples 7 to 8 and Comparative Examples 11 to 12 shows that the laminated sheet of the present invention is excellent in colorless transparency, weather resistance and gas barrier properties.
[0108]
In addition, a comparison between Example 9 and Comparative Example 13 shows that the laminated sheet of the present invention is significantly excellent in colorless transparency by using a thermoplastic copolymer having a polymerization temperature of 95 ° C. or lower.
[0109]
【The invention's effect】
As described above, according to the present invention, a sheet having excellent colorless transparency, excellent heat resistance, excellent abrasion resistance, oil resistance, chemical resistance, gas barrier property and weather resistance, and colorless transparency, An excellent laminated sheet can be provided in which the abrasion resistance, oil resistance, chemical resistance, gas barrier property and weather resistance are balanced. Therefore, the thermoplastic copolymer sheet and the laminated sheet of the present invention can be used for covers such as vending machine covers and lighting covers, civil engineering construction materials such as road transmissive plates, daylighting plates, road shelters, carports, and bathtub materials. , Garnish and other vehicle exteriors, and packaging materials for foods and pharmaceuticals, etc.

Claims (10)

(I) a thermoplastic copolymer comprising a glutaric anhydride unit represented by the following general formula (1) and (ii) an unsaturated carboxylic acid alkyl ester unit, or the units (i) and (ii) and ( iii) not containing a thermoplastic copolymer comprising unsaturated carboxylic acid units, or units (i) and (ii) or units (i), (ii) and (iii) and (iv) an aromatic ring It is a thermoplastic copolymer composed of other vinyl monomer units, and has an absorbance at a wavelength of 280 nm (where the absorbance is a value measured with an ultraviolet-visible spectrophotometer using a film having a thickness of 100 μm). Is 0.5 or less and a glass transition temperature is 130 ° C. or more.

(In the above formula, R ¹ and R ² represent the same or different hydrogen atoms or alkyl groups having 1 to 5 carbon atoms.) A monomer mixture containing an unsaturated carboxylic acid alkyl ester monomer and an unsaturated carboxylic acid monomer is polymerized at a temperature of 95 ° C. or lower to obtain (C) a raw copolymer, and then (C) a raw copolymer. The sheet according to claim 1, wherein the polymer is heated and (A) a thermoplastic copolymer is obtained by (a) a dealcoholization reaction and / or (b) a dehydration reaction. (Iii) The sheet according to claim 1 or 2, wherein the unsaturated carboxylic acid unit has a structure represented by the following general formula (2).

(However, R ³ represents hydrogen or an alkyl group having 1 to 5 carbon atoms) (Ii) The sheet according to any one of claims 1 to 3, wherein the unsaturated carboxylic acid alkyl ester unit has a structure represented by the following general formula (3).

(However, R ⁴ represents hydrogen or an alkyl group having 1 to ⁵ carbon atoms, and R ⁵ represents an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms or a hydroxyl group or halogen having at least one but no more than carbon atoms. Represents an aliphatic or alicyclic hydrocarbon group having 1 to 6 carbon atoms substituted with The sheet according to any one of claims 1 to 4, wherein the surface hardness is 4H or more in pencil hardness. A laminated sheet in which at least one of the surface layers is a layer comprising the thermoplastic copolymer (A) according to any one of claims 1 to 4. The laminated sheet according to claim 6, wherein the surface hardness of the surface layer (A) made of a thermoplastic copolymer is 4H or more in pencil hardness. The laminated sheet according to claim 6, further comprising (B) a base material, wherein the base material is a thermoplastic resin. 9. The laminated sheet according to claim 8, wherein the thermoplastic resin is a transparent resin. (A) The method for producing a laminated sheet according to any one of claims 6 to 9, wherein the thermoplastic copolymer and the thermoplastic resin are co-extruded integrally.