JP3765346B2 - Thermosetting resin composition, molding material containing the same, and artificial marble - Google Patents

Description

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等のチオエーテル系抗酸化剤が挙げられる。これら含硫黄抗酸化剤は、一種類のみを用いてもよく、また、二種類以上を併用してもよい。上記例示の含硫黄抗酸化剤のうち、化合物Ａ、および、化合物Ｇがより好ましい。
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熱硬化性樹脂組成物における含硫黄抗酸化剤の含有量は、特に限定されるものではないが、熱硬化性樹脂、および必要に応じて用いられる低収縮化剤（後述する）等の合成樹脂を含む全合成樹脂成分１００重量部に対して、含硫黄抗酸化剤を０．０５重量部〜３．０重量部の範囲内で添加することがより好ましく、０．１重量部〜１．５重量部の範囲内で添加することがさらに好ましい。含硫黄抗酸化剤の添加量が０．０５重量部よりも少ない場合には、含硫黄抗酸化剤を添加することにより得られる効果が乏しくなるおそれがある。また、含硫黄抗酸化剤の添加量が２．０重量部よりも多い場合には、熱硬化性樹脂が備えている各種物性を低下させるおそれがある。
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本発明にかかる含リン抗酸化剤としては、具体的には、例えば、
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ビスフェノールＡペンタエリスリトールホスファイト等のホスファイト系抗酸化剤が挙げられるが、特に限定されるものではない。これら含リン抗酸化剤は、必要に応じて、一種類のみを含硫黄抗酸化剤と併用してもよく、また、二種類以上を含硫黄抗酸化剤と併用してもよい。上記例示の含リン抗酸化剤のうち、化合物Ｂ、化合物Ｃ、化合物Ｄ、化合物Ｅ、および、化合物Ｆがより好ましい。
【００６４】
含硫黄抗酸化剤と含リン抗酸化剤とを併用する場合において、熱硬化性樹脂組成物における含リン抗酸化剤の含有量は、特に限定されるものではないが、熱硬化性樹脂、および必要に応じて用いられる低収縮化剤等の合成樹脂を含む全合成樹脂成分１００重量部に対して、含リン抗酸化剤を０．０５重量部〜２．０重量部の範囲内で添加することがより好ましく、０．１重量部〜１．０重量部の範囲内で添加することがさらに好ましく、０．２重量部〜０．６重量部の範囲内で添加することが特に好ましい。含リン抗酸化剤の添加量が０．０５重量部よりも少ない場合には、含リン抗酸化剤を併用することにより得られる相乗効果が乏しくなる。また、含リン抗酸化剤の添加量が２．０重量部よりも多い場合には、熱硬化性樹脂が備えている各種物性を低下させるおそれがある。
【００６５】
含硫黄抗酸化剤と含リン抗酸化剤とを併用する場合において、両者の重量比は、特に限定されるものではない。また、含硫黄抗酸化剤や含リン抗酸化剤を熱硬化性樹脂組成物、即ち、熱硬化性樹脂に添加する際の添加方法や、その時期（タイミング）等は、特に限定されるものではない。つまり、含硫黄抗酸化剤や含リン抗酸化剤は、熱硬化性樹脂組成物を硬化させる時点、具体的には、熱硬化性樹脂組成物を含む成形材料を成形する時点で、熱硬化性樹脂組成物に含まれていればよい。
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以上のように、本発明にかかる熱硬化性樹脂組成物は、熱硬化性樹脂と、前記一般式（１）で表される構造を有する含硫黄抗酸化剤と、必要に応じて含リン抗酸化剤とを含んでなる。これにより、熱水に長期間曝された場合の黄変等の変色に対する抑制効果に優れた熱硬化性樹脂組成物を提供することができる。また、含硫黄抗酸化剤と含リン抗酸化剤とを併用すると、両者の相乗効果により、黄変等の変色に対する抑制効果により一層優れた熱硬化性樹脂組成物を提供することができる。
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尚、熱硬化性樹脂組成物は、必要に応じて、従来公知のフェノール系抗酸化剤をさらに含んでなっていてもよい。つまり、本発明にかかる熱硬化性樹脂組成物においては、含硫黄抗酸化剤とフェノール系抗酸化剤とを併用することもでき、或いは、含硫黄抗酸化剤と含リン抗酸化剤とフェノール系抗酸化剤とを併用することもできる。
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本発明にかかる成形材料は、上記構成の熱硬化性樹脂組成物を含んでなる。さらに、成形材料は、必要に応じて、従来公知の副資材（添加剤）や補強材等を含んでいてもよい。上記の副資材としては、具体的には、例えば、硬化剤、増粘剤、充填剤、低収縮化剤、（内部）離型剤、顔料、減粘剤、カップリング剤等が挙げられる。本発明にかかる成形材料は、例えば、注型用材料、ＳＭＣ（シートモールディングコンパウンド）、ＢＭＣ（バルクモールディングコンパウンド）等として好適である。
【００６９】
上記の硬化剤としては、例えば、ベンゾイルパーオキサイド、ラウロイルパーオキサイド、メチルエチルケトンパーオキサイド、ｔ−ブチルパーオキシ−２−エチルヘキサノエート、ｔ−ブチルパーオキシオクトエート、ｔ−ブチルパーオキシベンゾエート、クメンヒドロパーオキサイド、シクロヘキサノンパーオキサイド、ジクミルパーオキサイド、ビス（４−ｔ−ブチルシクロヘキシル）パーオキシジカーボネート、１，１−ビス（ｔ−ヘキシルパーオキシ）−３，３，５−トリメチルシクロヘキサン等の有機過酸化物；２，２’−アゾビスイソブチロニトリル、２−フェニルアゾ−２，４−ジメチル−４−メトキシバレロニトリル等のアゾ化合物；等のラジカル重合開始剤が挙げられるが、特に限定されるものではない。これら硬化剤は、一種類のみを用いてもよく、また、二種類以上を併用してもよい。また、硬化剤の添加量は、その種類や熱硬化性樹脂との組み合わせ、成形材料の成形条件、或いは、成形材料を成形してなる成形品の用途や所望される物性等に応じて設定すればよく、特に限定されるものではない。
【００７０】
上記の増粘剤としては、例えば、酸化マグネシウム、酸化カルシウム、酸化亜鉛等の多価金属酸化物；水酸化マグネシウム、水酸化カルシウム、水酸化アルミニウム等の多価金属水酸化物；多官能イソシアネート；等が挙げられるが、特に限定されるものではない。これら増粘剤は、一種類のみを用いてもよく、また、二種類以上を併用してもよい。増粘剤の使用量は、その種類や熱硬化性樹脂との組み合わせ、熱硬化性樹脂の重量平均分子量や粘度、成形品の用途や所望される物性等に応じて設定すればよく、特に限定されるものではない。
【００７１】
上記の充填剤としては、例えば、水酸化アルミニウム、炭酸カルシウム、硫酸カルシウム、硫酸バリウム、アルミナ、クレー、タルク、ミルドファイバー、シリカ（珪砂）、川砂、珪藻土、雲母粉末、石膏、寒水石、ガラス粉末、ガラス球、ポリマービーズ等の、無機充填剤および有機充填剤が挙げられるが、特に限定されるものではない。これら充填剤は、一種類のみを用いてもよく、また、二種類以上を併用してもよい。また、充填剤の配合量は、その種類や熱硬化性樹脂との組み合わせ、成形材料の成形条件、或いは、成形品の用途や所望される物性等に応じて設定すればよく、特に限定されるものではない。尚、充填剤を適宜選択することにより、成形品にいわゆる透明感を付与することもできる。
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上記の低収縮化剤としては、例えば、ポリエチレン、ポリプロピレン、ポリスチレン、三次元架橋ポリスチレン、ポリメタクリル酸メチル、ポリエチレングリコール、ポリプロピレングリコール、セルロースブチレート、アセテート、ポリ塩化ビニル、ポリ酢酸ビニル、ポリカプロラクトン、飽和ポリエステル等が挙げられるが、特に限定されるものではない。これら低収縮化剤は、一種類のみを用いてもよく、また、二種類以上を併用してもよい。また、低収縮化剤の添加量は、その種類や熱硬化性樹脂との組み合わせ、成形材料の成形条件、或いは、成形品の用途や所望される物性等に応じて設定すればよく、特に限定されるものではない。低収縮化剤を添加することにより、成形材料を成形してなる成形品の寸法安定性をより一層向上させることができる。
【００７３】
上記の離型剤としては、例えば、ステアリン酸、ステアリン酸亜鉛、ステアリン酸アルミニウム、ステアリン酸カルシウム、ステアリン酸バリウム、ステアリン酸アミド、ラウリル酸、トリフェニルホスフェート、アルキルホスフェート等が挙げられるが、特に限定されるものではない。また、一般に用いられているワックス類、シリコーンオイル等の離型剤を用いることもできる。これら離型剤は、一種類のみを用いてもよく、また、二種類以上を併用してもよい。また、離型剤の添加量は、その種類や熱硬化性樹脂との組み合わせ、成形材料の成形条件、或いは、成形品の用途や所望される物性等に応じて設定すればよく、特に限定されるものではない。
【００７４】
上記の顔料は、特に限定されるものではなく、従来より熱硬化性樹脂に使用されている無機顔料や有機顔料を用いることができる。顔料の添加量は、特に限定されるものではなく、成形品の用途等に応じて適宜設定すればよい。
【００７５】
上記の減粘剤は、特に限定されるものではなく、従来より熱硬化性樹脂に使用されている減粘剤を用いることができる。また、上記のカップリング剤は、特に限定されるものではなく、従来より熱硬化性樹脂に使用されているカップリング剤を用いることができる。
【００７６】
上記の補強材としては、例えば、ガラス繊維、炭素繊維、金属繊維、セラミックからなる繊維等の無機繊維；アラミドやポリエステル等からなる有機繊維；天然繊維等が挙げられるが、特に限定されるものではない。また、繊維の形態は、例えば、ロービング、チョップトストランド、マット、クロス（織物）等が挙げられるが、特に限定されるものではない。これら補強材は、一種類のみを用いてもよく、また、二種類以上を併用してもよい。また、補強材の使用量は、その種類や熱硬化性樹脂との組み合わせ、成形品の用途や所望される物性等に応じて設定すればよく、特に限定されるものではない。
【００７７】
また、熱硬化性樹脂組成物と補強材とを混合する方法は、特に限定されるものではなく、該補強材の形態に応じて適宜設定すればよい。例えば、補強材の形態がマットやクロス等である場合には、該補強材に熱硬化性樹脂組成物を含浸させればよい。また、例えば、補強材の形態がロービングやチョップトストランド等である場合には、該補強材と熱硬化性樹脂組成物とを混練すればよい。補強材を含む成形材料は、例えばＳＭＣやＢＭＣとして好適である。
【００７８】
本発明にかかる成形材料の製造方法、つまり、熱硬化性樹脂組成物に上記副資材や補強材を添加する方法は、特に限定されるものではない。また、成形材料の硬化方法や硬化条件、つまり、成形品の製造方法は、特に限定されるものではない。
【００７９】
以上のように、本発明にかかる成形材料は、上記構成の熱硬化性樹脂組成物を含んでなる。該成形材料は、種々の成形方法に適用可能である。上記の成形材料を成形してなる成形品は、熱水に長期間曝された場合の黄変等の変色に対する抑制効果に優れており、経時変化による変色が従来の成形品と比較して低減されるので、美観（外観）を損なうことがなく、耐久性が向上する。成形材料を成形してなる成形品は、例えば、人工大理石として好適であり、浴槽（バスタブ）や洗面台（カウンター）、流し台（シンク）等、温水や熱水を使用する場所に好適に用いられる。
【００８０】
【実施例】
以下、実施例および比較例により、本発明をさらに詳細に説明するが、本発明はこれらにより何ら限定されるものではない。尚、実施例および比較例に記載の「部」は、「重量部」を示す。
【００８１】
〔実施例１〕
不飽和ポリエステル７０部およびビニルエステル樹脂１８部からなる熱硬化性樹脂８８部に、含硫黄抗酸化剤としての前記化合物Ａ（旭電化工業株式会社製；商品名 アデカスタブ ＡＯ−２３）０．５部を添加し、均一に混合することにより、本発明にかかる熱硬化性樹脂組成物を調製した。
【００８２】
上記の不飽和ポリエステルは、無水マレイン酸と、水素化ビスフェノールＡと、プロピレングリコールとをモル比が「１．００：０．３０：０．７５」となるように用いて縮合させた後、得られた重合体を、スチレンの割合が４５重量％となるように該スチレンに溶解することにより製造した。また、上記のビニルエステル樹脂は、ビスフェノールタイプのエポキシ樹脂１．００モル（エポキシ当量として）に対して、メタクリル酸１．０５モルの割合で用いて付加重合させて得られた反応物を、スチレンの割合が４５重量％となるように該スチレンに溶解することにより製造した。
【００８３】
次に、上記の熱硬化性樹脂組成物に、硬化剤としての１，１−ビス（ｔ−ヘキシルパーオキシ）−３，３，５−トリメチルシクロヘキサン１部、充填剤としての水酸化アルミニウム１５０部、低収縮化剤としての三次元架橋ポリスチレン粒子１２部、増粘剤としての酸化マグネシウム０．７部、および、離型剤としてのステアリン酸亜鉛４部を加えて混合した。
【００８４】
次いで、得られたコンパウンドをＳＭＣ製造装置に適用し、補強材としてのガラス繊維６０部に含浸させることにより、本発明にかかる成形材料としてのＳＭＣを製造した。上記のＳＭＣを、１１０℃〜１５０℃に加熱された金型を用い、所定の成形条件で加熱加圧成形した。これにより、厚みが約４ｍｍの成形品を製造した。
【００８５】
得られた成形品の耐久性、つまり、熱水に長期間曝された場合の黄変等の変色に対する抑制効果を評価するために、以下に示す試験を行った。即ち、先ず、成形品の黄色度（ＹＩ）を色差計（日本電色工業株式会社製・ＳＺ−Σ９０）を用いて測定した。次に、成形品を９８℃の熱水に１００時間浸漬し、浸漬後の成形品の黄色度と色差（ΔＥ）とを上記色差計を用いて測定した。そして、浸漬前の成形品の黄色度と、浸漬後の成形品の黄色度との差を求め、この数値を黄変度（ΔＹＩ）とした。尚、上記の試験において、浸漬時間１００時間は、例えば成形品が浴槽である場合には、該浴槽に４０℃〜５０℃の温水を満たし、毎日４時間、３年〜５年にわたって使用した場合に相当する。
【００８６】
また、上記と同様にして、成形品を９８℃の熱水に２００時間浸漬した後、並びに３００時間浸漬した後の、該成形品の黄色度と色差とを測定すると共に、黄変度を求めた。上記の試験結果、即ち、色差および黄変度を、表１にまとめて記載した。
【００８７】
〔比較例１〕
熱硬化性樹脂に前記化合物Ａを添加しない以外は、実施例１の操作等と同様の操作等を行って、比較用のＳＭＣ（比較用成形材料）を製造した。つまり、実施例１において、含硫黄抗酸化剤を用いないで比較用ＳＭＣを製造した。
【００８８】
上記の比較用ＳＭＣを、実施例１のＳＭＣの成形条件と同一の成形条件で加熱加圧成形した。これにより、厚みが約４ｍｍの比較用の成形品を製造した。次いで、実施例１と同様にして、得られた比較用成形品の色差および黄変度を測定した。上記の色差および黄変度を、表１にまとめて記載した。
【００８９】
〔実施例２〕
不飽和ポリエステル７０部およびビニルエステル樹脂１８部からなる熱硬化性樹脂８８部に、含硫黄抗酸化剤としての前記化合物Ａ（同社製・アデカスタブ ＡＯ−２３）０．３部と、含リン抗酸化剤としての前記化合物Ｃ（旭電化工業株式会社製；商品名 アデカスタブ ＰＥＰ−３６）０．３部とを添加し、均一に混合することにより、本発明にかかる熱硬化性樹脂組成物を調製した。尚、上記の不飽和ポリエステルおよびビニルエステル樹脂の組成は、実施例１で用いた不飽和ポリエステルおよびビニルエステル樹脂の組成と同一である。
【００９０】
次に、上記の熱硬化性樹脂組成物に、１，１−ビス（ｔ−ヘキシルパーオキシ）−３，３，５−トリメチルシクロヘキサン１部、水酸化アルミニウム１５０部、三次元架橋ポリスチレン粒子１２部、酸化マグネシウム０．７部、および、ステアリン酸亜鉛４部を加えて混合した。
【００９１】
次いで、得られたコンパウンドをＳＭＣ製造装置に適用し、補強材としてのガラス繊維６０部に含浸させることにより、本発明にかかる成形材料としてのＳＭＣを製造した。上記のＳＭＣを、実施例１のＳＭＣの成形条件と同一の成形条件で加熱加圧成形した。これにより、厚みが約４ｍｍの成形品を製造した。次いで、実施例１と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表１にまとめて記載した。
【００９２】
〔比較例２〕
熱硬化性樹脂に前記化合物Ａを添加しない以外は、実施例２の操作等と同様の操作等を行って、比較用のＳＭＣ（比較用成形材料）を製造した。つまり、実施例２において、含硫黄抗酸化剤を用いないで比較用ＳＭＣを製造した。
【００９３】
上記の比較用ＳＭＣを、実施例１のＳＭＣの成形条件と同一の成形条件で加熱加圧成形した。これにより、厚みが約４ｍｍの比較用の成形品を製造した。次いで、実施例１と同様にして、得られた比較用成形品の色差および黄変度を測定した。上記の色差および黄変度を、表１にまとめて記載した。
【００９４】
【表１】

【００９５】
実施例１と比較例１との対比から明らかなように、含硫黄抗酸化剤が添加されているＳＭＣを成形してなる成形品は、含硫黄抗酸化剤が添加されていない比較用ＳＭＣを成形してなる比較用成形品と比較して、色差および黄変度の経時変化が低減されていることがわかる。即ち、本発明にかかるＳＭＣを成形してなる成形品は、熱水に長期間曝された場合における変色に対する抑制効果に優れていることがわかる。
【００９６】
また、実施例１と実施例２との対比、並びに、実施例２と比較例２との対比から明らかなように、含硫黄抗酸化剤と含リン抗酸化剤とが添加されているＳＭＣを成形してなる成形品は、両者の相乗効果により、色差および黄変度の経時変化がより一層低減されていることがわかる。
【００９７】
尚、比較例１と比較例２との対比から明らかなように、含リン抗酸化剤のみが添加されている比較用ＳＭＣを成形してなる比較用成形品は、浸漬時間が１００時間の時点では色差および黄変度の経時変化が低減されているものの、浸漬時間が２００時間を越えると色差および黄変度の経時変化が顕著となっている。つまり、含リン抗酸化剤のみを用いてなる比較用成形品は、含リン抗酸化剤を用いないでなる比較用成形品よりも、変色が促進されてしまっている。
【００９８】
〔実施例３〕
熱硬化性樹脂としてのアクリルシラップ１００部に、含硫黄抗酸化剤としての前記化合物Ａ（同社製・アデカスタブ ＡＯ−２３）０．６部を添加し、均一に混合することにより、本発明にかかる熱硬化性樹脂組成物を調製した。
【００９９】
上記のアクリルシラップは、メチルメタクリレートと、メタクリル酸と、エチレングリコールジメタクリレートとを重量比が「９１．７：３．３：５．０」となるように用いると共に、上記メチルメタクリレートを部分重合することにより製造した。
【０１００】
次に、上記の熱硬化性樹脂組成物に、１，１−ビス（ｔ−ヘキシルパーオキシ）−３，３，５−トリメチルシクロヘキサン１部、水酸化アルミニウム１５０部、酸化マグネシウム０．７部、および、ステアリン酸亜鉛４部を加えて混合した。これにより、本発明にかかる成形材料を製造した。
【０１０１】
上記の成形材料を、８０℃〜１３０℃に加熱された金型を用い、所定の成形条件で加熱加圧成形した。これにより、厚みが約７ｍｍの成形品を製造した。次いで、実施例１と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表２にまとめて記載した。
【０１０２】
〔比較例３〕
熱硬化性樹脂に前記化合物Ａを添加しない以外は、実施例３の操作等と同様の操作等を行って、比較用の成形材料を製造した。つまり、実施例３において、含硫黄抗酸化剤を用いないで比較用成形材料を製造した。
【０１０３】
上記の比較用成形材料を、実施例３の成形材料の成形条件と同一の成形条件で加熱加圧成形した。これにより、厚みが約７ｍｍの比較用の成形品を製造した。次いで、実施例１と同様にして、得られた比較用成形品の色差および黄変度を測定した。上記の色差および黄変度を、表２にまとめて記載した。
【０１０４】
〔実施例４〕
熱硬化性樹脂としてのアクリルシラップ１００部に、含硫黄抗酸化剤としての前記化合物Ａ（同社製・アデカスタブ ＡＯ−２３）０．３部と、含リン抗酸化剤としての前記化合物Ｃ（同社製・アデカスタブ ＰＥＰ−３６）０．３部とを添加し、均一に混合することにより、本発明にかかる熱硬化性樹脂組成物を調製した。尚、上記のアクリルシラップの組成は、実施例３で用いたアクリルシラップの組成と同一である。
【０１０５】
次に、上記の熱硬化性樹脂組成物に、１，１−ビス（ｔ−ヘキシルパーオキシ）−３，３，５−トリメチルシクロヘキサン１部、水酸化アルミニウム１５０部、酸化マグネシウム０．７部、および、ステアリン酸亜鉛４部を加えて混合した。これにより、本発明にかかる成形材料を製造した。
【０１０６】
上記の成形材料を、実施例３の成形材料の成形条件と同一の成形条件で加熱加圧成形した。これにより、厚みが約７ｍｍの成形品を製造した。次いで、実施例１と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表２にまとめて記載した。
【０１０７】
【表２】

【０１０８】
実施例３と比較例３との対比から明らかなように、含硫黄抗酸化剤が添加されている成形材料を成形してなる成形品は、含硫黄抗酸化剤が添加されていない比較用成形材料を成形してなる比較用成形品と比較して、色差および黄変度の経時変化が低減されていることがわかる。即ち、本発明にかかる成形材料を成形してなる成形品は、熱水に長期間曝された場合における変色に対する抑制効果に優れていることがわかる。
【０１０９】
また、実施例３と実施例４との対比から明らかなように、含硫黄抗酸化剤と含リン抗酸化剤とが添加されている成形材料を成形してなる成形品は、両者の相乗効果により、色差および黄変度の経時変化がより一層低減されていることがわかる。
【０１１０】
〔実施例５〕
実施例１で用いた熱硬化性樹脂の組成と同一の組成の熱硬化性樹脂、即ち、不飽和ポリエステル７０部およびビニルエステル樹脂１８部からなる熱硬化性樹脂８８部に、含硫黄抗酸化剤としての前記化合物Ａ（同社製・アデカスタブ ＡＯ−２３）０．２３部と、含リン抗酸化剤としての前記化合物Ｆ（同社製・アデカスタブ １５００）０．２３部とを添加し、均一に混合することにより、本発明にかかる熱硬化性樹脂組成物を調製した。
【０１１１】
次に、上記の熱硬化性樹脂組成物に、１，１−ビス（ｔ−ヘキシルパーオキシ）−３，３，５−トリメチルシクロヘキサン１部、水酸化アルミニウム１５０部、三次元架橋ポリスチレン粒子１２部、酸化マグネシウム０．７部、および、ステアリン酸亜鉛４部を加えて混合した。
【０１１２】
次いで、得られたコンパウンドをＳＭＣ製造装置に適用し、補強材としてのガラス繊維６０部に含浸させることにより、本発明にかかる成形材料としてのＳＭＣを製造した。上記のＳＭＣを、実施例１のＳＭＣの成形条件と同一の成形条件で加熱加圧成形した。これにより、厚みが約４ｍｍの成形品を製造した。次いで、実施例１と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表３にまとめて記載した。
【０１１３】
〔実施例６〕
化合物Ｆ０．２３部の代わりに、含リン抗酸化剤としての前記化合物Ｅ（同社製・アデカスタブ ２６０）０．２３部を添加した以外は、実施例５の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例５と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表３にまとめて記載した。
【０１１４】
〔実施例７〕
化合物Ｆ０．２３部の代わりに、含リン抗酸化剤としての前記化合物Ｂ（同社製・アデカスタブ ＰＥＰ−２４Ｇ）０．２３部を添加した以外は、実施例５の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例５と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表３にまとめて記載した。
【０１１５】
〔比較例４〕
熱硬化性樹脂に前記化合物Ａと前記化合物Ｆとを添加しない以外は、実施例５の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの比較用の成形品を製造した。つまり、実施例５において、含硫黄抗酸化剤と含リン抗酸化剤とを用いないで比較用成形品を製造した。次いで、実施例５と同様にして、得られた比較用成形品の色差および黄変度を測定した。上記の色差および黄変度を、表３にまとめて記載した。
【０１１６】
【表３】

【０１１７】
実施例５〜７と比較例４との対比から明らかなように、含硫黄抗酸化剤と含リン抗酸化剤とが添加されているＳＭＣを成形してなる成形品は、含硫黄抗酸化剤と含リン抗酸化剤とが添加されていない比較用ＳＭＣを成形してなる比較用成形品と比較して、色差および黄変度の経時変化が低減されていることがわかる。即ち、本発明にかかるＳＭＣを成形してなる成形品は、熱水に長期間曝された場合における変色に対する抑制効果に優れていることがわかる。
【０１１８】
〔実施例８〕
実施例１で用いた熱硬化性樹脂の組成と同一の組成の熱硬化性樹脂、即ち、不飽和ポリエステル７０部およびビニルエステル樹脂１８部からなる熱硬化性樹脂８８部に、含硫黄抗酸化剤としての前記化合物Ｇ（同社製・アデカスタブ ＡＯ−４１２Ｓ）０．３部を添加し、均一に混合することにより、本発明にかかる熱硬化性樹脂組成物を調製した。
【０１１９】
次に、上記の熱硬化性樹脂組成物に、１，１−ビス（ｔ−ヘキシルパーオキシ）−３，３，５−トリメチルシクロヘキサン１部、水酸化アルミニウム１５０部、三次元架橋ポリスチレン粒子１２部、酸化マグネシウム０．７部、および、ステアリン酸亜鉛４部を加えて混合した。
【０１２０】
次いで、得られたコンパウンドをＳＭＣ製造装置に適用し、補強材としてのガラス繊維６０部に含浸させることにより、本発明にかかる成形材料としてのＳＭＣを製造した。上記のＳＭＣを、実施例１のＳＭＣの成形条件と同一の成形条件で加熱加圧成形した。これにより、厚みが約４ｍｍの成形品を製造した。次いで、成形品を浸漬する熱水の温度を９８℃から９０℃に変更した以外は、実施例１と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表４にまとめて記載した。
【０１２１】
〔実施例９〕
化合物Ｇの添加量を０．３部から０．５部に変更した以外は、実施例８の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例８と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表４にまとめて記載した。
【０１２２】
〔実施例１０〕
化合物Ｇの添加量を０．３部から０．８部に変更した以外は、実施例８の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例８と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表４にまとめて記載した。
【０１２３】
〔実施例１１〕
熱硬化性樹脂に、含硫黄抗酸化剤としての前記化合物Ｇ（同社製・アデカスタブ ＡＯ−４１２Ｓ）０．３部と、含リン抗酸化剤としての前記化合物Ｆ（同社製・アデカスタブ １５００）０．３部とを添加した以外は、実施例８の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例８と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表４にまとめて記載した。
【０１２４】
〔実施例１２〕
熱硬化性樹脂に、含硫黄抗酸化剤としての前記化合物Ｇ（同社製・アデカスタブ ＡＯ−４１２Ｓ）０．３部と、含リン抗酸化剤としての前記化合物Ｅ（同社製・アデカスタブ ２６０）０．３部とを添加した以外は、実施例８の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例８と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表４にまとめて記載した。
【０１２５】
〔実施例１３〕
熱硬化性樹脂に、含硫黄抗酸化剤としての前記化合物Ｇ（同社製・アデカスタブ ＡＯ−４１２Ｓ）０．３部と、含リン抗酸化剤としての前記化合物Ｃ（同社製・アデカスタブ ＰＥＰ−３６）０．３部とを添加した以外は、実施例８の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例８と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表４にまとめて記載した。
【０１２６】
〔比較例５〕
熱硬化性樹脂に前記化合物Ｇを添加しない以外は、実施例８の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの比較用の成形品を製造した。つまり、実施例８において、含硫黄抗酸化剤を用いないで比較用成形品を製造した。次いで、実施例８と同様にして、得られた比較用成形品の色差および黄変度を測定した。上記の色差および黄変度を、表４にまとめて記載した。
【０１２７】
【表４】

【０１２８】
実施例８〜１０と比較例５との対比から明らかなように、含硫黄抗酸化剤が添加されているＳＭＣを成形してなる成形品は、含硫黄抗酸化剤が添加されていない比較用ＳＭＣを成形してなる比較用成形品と比較して、色差および黄変度の経時変化が低減されていることがわかる。即ち、本発明にかかるＳＭＣを成形してなる成形品は、熱水に長期間曝された場合における変色に対する抑制効果に優れていることがわかる。
【０１２９】
また、実施例８と実施例１１〜１３との対比から明らかなように、含硫黄抗酸化剤と含リン抗酸化剤とが添加されている成形材料を成形してなる成形品は、両者の相乗効果により、色差および黄変度の経時変化がより一層低減されていることがわかる。
【０１３０】
〔実施例１４〕
熱硬化性樹脂としての不飽和ポリエステル８８部に、含硫黄抗酸化剤としての前記化合物Ａ（同社製・アデカスタブ ＡＯ−２３）０．５部を添加し、均一に混合することにより、本発明にかかる熱硬化性樹脂組成物を調製した。尚、上記の不飽和ポリエステルの組成は、実施例１で用いた不飽和ポリエステルの組成と同一である。
【０１３１】
次に、上記の熱硬化性樹脂組成物に、１，１−ビス（ｔ−ヘキシルパーオキシ）−３，３，５−トリメチルシクロヘキサン１部、水酸化アルミニウム１５０部、三次元架橋ポリスチレン粒子１２部、酸化マグネシウム０．７部、および、ステアリン酸亜鉛４部を加えて混合した。
【０１３２】
次いで、得られたコンパウンドをＳＭＣ製造装置に適用し、補強材としてのガラス繊維６０部に含浸させることにより、本発明にかかる成形材料としてのＳＭＣを製造した。上記のＳＭＣを、実施例１のＳＭＣの成形条件と同一の成形条件で加熱加圧成形した。これにより、厚みが約４ｍｍの成形品を製造した。次いで、成形品を浸漬する熱水の温度を９８℃から９０℃に変更した以外は、実施例１と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表５にまとめて記載した。
【０１３３】
〔実施例１５〕
熱硬化性樹脂に、含硫黄抗酸化剤としての前記化合物Ａ（同社製・アデカスタブ ＡＯ−２３）０．３部と、含リン抗酸化剤としての前記化合物Ｃ（同社製・アデカスタブ ＰＥＰ−３６）０．３部とを添加した以外は、実施例１４の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例１４と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表５にまとめて記載した。
【０１３４】
〔比較例６〕
熱硬化性樹脂に前記化合物Ａを添加しない以外は、実施例１４の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの比較用の成形品を製造した。つまり、実施例１４において、含硫黄抗酸化剤を用いないで比較用成形品を製造した。次いで、実施例１４と同様にして、得られた比較用成形品の色差および黄変度を測定した。上記の色差および黄変度を、表５にまとめて記載した。
【０１３５】
〔実施例１６〕
不飽和ポリエステル８８部の代わりに、不飽和ポリエステル７９．２部およびビニルエステル樹脂８．８部からなる熱硬化性樹脂８８部を用いた以外は、実施例１４の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。尚、上記の不飽和ポリエステルおよびビニルエステル樹脂の組成は、実施例１で用いた不飽和ポリエステルおよびビニルエステル樹脂の組成と同一である。
【０１３６】
次いで、実施例１４と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表５にまとめて記載した。
【０１３７】
〔実施例１７〕
不飽和ポリエステル８８部の代わりに、実施例１６で用いた熱硬化性樹脂８８部を用いた以外は、実施例１５の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例１４と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表５にまとめて記載した。
【０１３８】
〔比較例７〕
不飽和ポリエステル８８部の代わりに、実施例１６で用いた熱硬化性樹脂８８部を用いた以外は、比較例６の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの比較用の成形品を製造した。つまり、実施例１６において、含硫黄抗酸化剤を用いないで比較用成形品を製造した。次いで、実施例１４と同様にして、得られた比較用成形品の色差および黄変度を測定した。上記の色差および黄変度を、表５にまとめて記載した。
【０１３９】
〔実施例１８〕
不飽和ポリエステル８８部の代わりに、不飽和ポリエステル６１．６部およびビニルエステル樹脂２６．４部からなる熱硬化性樹脂８８部を用いた以外は、実施例１４の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。尚、上記の不飽和ポリエステルおよびビニルエステル樹脂の組成は、実施例１で用いた不飽和ポリエステルおよびビニルエステル樹脂の組成と同一である。
【０１４０】
次いで、実施例１４と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表５にまとめて記載した。
【０１４１】
〔実施例１９〕
不飽和ポリエステル８８部の代わりに、実施例１８で用いた熱硬化性樹脂８８部を用いた以外は、実施例１５の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの成形品を製造した。次いで、実施例１４と同様にして、得られた成形品の色差および黄変度を測定した。上記の色差および黄変度を、表５にまとめて記載した。
【０１４２】
〔比較例８〕
不飽和ポリエステル８８部の代わりに、実施例１８で用いた熱硬化性樹脂８８部を用いた以外は、比較例６の操作並びに加熱加圧成形等と同様の操作並びに加熱加圧成形等を行って、厚みが約４ｍｍの比較用の成形品を製造した。つまり、実施例１８において、含硫黄抗酸化剤を用いないで比較用成形品を製造した。次いで、実施例１４と同様にして、得られた比較用成形品の色差および黄変度を測定した。上記の色差および黄変度を、表５にまとめて記載した。
【０１４３】
【表５】

【０１４４】
実施例１４・１５と比較例６との対比、実施例１６・１７と比較例７との対比、並びに、実施例１８・１９と比較例８との対比から明らかなように、含硫黄抗酸化剤が添加されているＳＭＣを成形してなる成形品は、含硫黄抗酸化剤が添加されていない比較用ＳＭＣを成形してなる比較用成形品と比較して、色差および黄変度の経時変化が低減されていることがわかる。即ち、本発明にかかるＳＭＣを成形してなる成形品は、熱水に長期間曝された場合における変色に対する抑制効果に優れていることがわかる。
【０１４５】
そして、上記実施例１〜１９の結果から明らかなように、本発明にかかる成形材料は、熱水に長期間曝された場合の黄変等の変色に対する抑制効果に優れているので、該成形材料を用いて例えば浴槽等の成形品を製造すると、該成形品は、経時変化による変色が従来の成形品と比較して低減される。従って、該成形品は、美観（外観）を損なうことがないので、耐久性が向上する。
【０１４６】
【発明の効果】
本発明の熱硬化性樹脂組成物は、以上のように、不飽和ポリエステル、ビニルエステル樹脂、および、（メタ）アクリルシラップからなる群より選ばれる少なくとも一種のラジカル重合型樹脂と、一般式（１）
Ｒ_a −Ｓ−ＣＨ₂ −ＣＨ₂ −ＣＯＯＲ_b ……（１）
（式中、Ｒ_a 、Ｒ_b は、それぞれ独立して有機残基を表す）
で表される含硫黄抗酸化剤とを含む構成である。
【０１４７】
これにより、所定の熱硬化性樹脂を含み、熱水に長期間曝された場合の黄変等の変色に対する抑制効果に優れた熱硬化性樹脂組成物を提供することができるという効果を奏する。
【０１４８】
また、本発明の熱硬化性樹脂組成物は、以上のように、不飽和ポリエステルと、ビニルエステル樹脂と、一般式（１）
Ｒ _a −Ｓ−ＣＨ ₂ −ＣＨ ₂ −ＣＯＯＲ _b ……（１）
（式中、Ｒ _a 、Ｒ _b は、それぞれ独立して有機残基を表す）
で表される含硫黄抗酸化剤とを含む構成である。
【０１４９】
これにより、所定の熱硬化性樹脂を含み、熱水に長期間曝された場合の黄変等の変色に対する抑制効果に優れた熱硬化性樹脂組成物を提供することができるという効果を奏する。
【０１５０】
本発明の熱硬化性樹脂組成物では、以上のように、含リン抗酸化剤をさらに含む構成であることが好ましい。
【０１５１】
これにより、含硫黄抗酸化剤と含リン抗酸化剤との相乗効果により、熱水に長期間曝された場合の黄変等の変色に対する抑制効果により一層優れた熱硬化性樹脂組成物を提供することができるという効果を奏する。
【０１５２】
本発明の成形材料は、以上のように、上記本発明の熱硬化性樹脂組成物を含む構成であることが好ましい。
【０１５３】
これにより、熱水に長期間曝された場合の黄変等の変色に対する抑制効果により一層優れた成形材料を提供することができる。該成形材料を用いて例えば浴槽等の成形品を製造すると、該成形品は、経時変化による変色が従来の成形品と比較して低減されるので、美観（外観）を損なうことがなく、耐久性が向上するという効果を奏する。 [0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a thermosetting resin composition and a molding material containing the same. A molded product formed by molding the molding material is preferably used in places where hot water or hot water is used, such as a bathtub (bathtub), a washstand (counter), a sink (sink), and the like.
[0002]
[Prior art]
  For example, JP-A-6-248168 and JP-A-7-11117 disclose an unsaturated polyester composition obtained by adding a phosphite antioxidant to an unsaturated polyester which is a kind of thermosetting resin. It is disclosed. Since the unsaturated polyester composition contains a phosphite antioxidant, discoloration such as yellowing during molding and yellowing when exposed to hot water for a long period of time is suppressed.
[0003]
[Problems to be solved by the invention]
  However, it is difficult to say that the conventional unsaturated polyester composition containing a phosphite antioxidant sufficiently suppresses discoloration such as yellowing when exposed to hot water for a long period of time. That is, in the conventional configuration comprising a phosphite-based antioxidant, the effect of suppressing discoloration such as yellowing is insufficient, for example, when a bathtub or the like is produced using the unsaturated polyester composition, As the bathtub is used, the color of the bathtub changes with time. Therefore, the conventional thermosetting resin composition has a problem that the effect of suppressing discoloration such as yellowing is insufficient, and the appearance (appearance) is impaired, resulting in poor durability.
[0004]
  The present invention has been made in view of the above-described conventional problems, and the purpose thereof is a thermosetting resin composition excellent in the effect of suppressing discoloration such as yellowing when exposed to hot water for a long time, and Another object is to provide a molding material containing the same.
[0005]
[Means for Solving the Problems]
  In order to solve the above-mentioned conventional problems, the inventors of the present application have made extensive studies on a thermosetting resin composition and a molding material containing the same. As a result, a thermosetting resin composition containing a sulfur-containing antioxidant having a specific structure, and a yellowing when a molding material containing the thermosetting resin composition is exposed to hot water for a long period of time, etc. As a result, the present invention has been completed.
[0006]
  That is,Of the present inventionIn order to solve the above problems, the thermosetting resin compositionAt least one radical polymerization resin selected from the group consisting of unsaturated polyester, vinyl ester resin, and (meth) acrylic syrup;General formula (1)
    R_a-S-CH₂-CH₂-COOR_b    ...... (1)
    (Wherein R_a, R_bEach independently represents an organic residue)
Sulfur-containing antioxidant represented byWhenIt is characterized by including.
[0007]
  the aboveAccording to the configurationIncluding a predetermined thermosetting resin,It is possible to provide a thermosetting resin composition having an excellent inhibitory effect on discoloration such as yellowing when exposed to hot water for a long period of time.
[0008]
  Of the present inventionIn order to solve the above problems, the thermosetting resin compositionUnsaturated polyester, vinyl ester resin, and general formula (1)
R _a -S-CH ₂ -CH ₂ -COOR _b ...... (1)
(Wherein R _a , R _b Each independently represents an organic residue)
A sulfur-containing antioxidant represented byIt is characterized by including.
[0009]
  the aboveAccording to the configurationA thermosetting resin composition containing a predetermined thermosetting resin and having an excellent effect of suppressing discoloration such as yellowing when exposed to hot water for a long period of time can be provided.
[0010]
  The thermosetting resin composition of the present invention preferably further contains a phosphorus-containing antioxidant.
[0011]
  According to the above configuration, the thermosetting resin composition is more excellent in suppressing the discoloration such as yellowing when exposed to hot water for a long time due to the synergistic effect of the sulfur-containing antioxidant and the phosphorus-containing antioxidant. Things can be provided.
[0012]
  Moreover, in order to solve said subject, the molding material of this invention is characterized by including the thermosetting resin composition of the said invention.
[0013]
  According to the said structure, the still more excellent molding material can be provided by the inhibitory effect with respect to discoloration, such as yellowing, when exposed to hot water for a long period of time. For example, when a molded product such as a bathtub is manufactured using the molding material, the discoloration due to aging is reduced compared to a conventional molded product, so that the appearance (appearance) is not impaired and the durability is improved. Improve. Moreover, it is preferable that the said molding material is used for a bathtub, a washstand, or a sink.
[0014]
The artificial marble of the present invention is characterized by comprising the molding material of the present invention.
[0015]
  The present invention is described in detail below.
[0016]
  The thermosetting resin composition according to the present invention comprises a thermosetting resin, a sulfur-containing antioxidant having a specific structure, and, if necessary, a phosphorus-containing antioxidant.
[0017]
  The thermosetting resin is not particularly limited, and any conventionally known thermosetting resin that can be used as a molding material can be employed. However, unsaturated polyester, vinyl ester resin, and At least one radical polymerization type resin selected from the group consisting of (meth) acrylic syrup is more preferable, and it is more preferable to include unsaturated polyester and vinyl ester resin.
[0018]
  The unsaturated polyester is a radical formed by dissolving, in a vinyl monomer, a polymer having a weight average molecular weight (Mw) of several hundred to several tens of thousands obtained by condensing an acid component and an alcohol component by a conventional method. It is a polymerization type resin.
[0019]
  Examples of the acid component include unsaturated dibasic acids such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, mesaconic acid, citraconic acid, citraconic anhydride; phthalic acid, phthalic anhydride, tetrahydrophthal Acids, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, halogenated phthalic anhydride, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, het acid, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, etc. A saturated dibasic acid; a tribasic or higher polybasic acid such as trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic dianhydride; and the like. These acid components may be used alone or in combination of two or more.
[0020]
  Examples of the alcohol component include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, and bisphenol A. , Glycols such as hydrogenated bisphenol A, propylene oxide adducts of bisphenol A, ethylene oxide adducts of bisphenol A; trifunctional or higher alcohols such as glycerin, trimethylolpropane, pentaerythritol; epoxides such as ethylene oxide, propylene oxide, epichlorohydrin, etc. And the like. These alcohol components may be used alone or in combination of two or more.
[0021]
  The method for reacting the acid component and the alcohol component is not particularly limited. The reaction conditions such as reaction temperature and reaction time may be appropriately set according to, for example, the types and combinations of acid components and alcohol components, or various physical properties desired for the unsaturated polyester or molding material. In addition, the combination of the acid component and the alcohol component, the amount used, and the like are not particularly limited. Moreover, the polymer obtained may be modified with various components such as a diene compound such as dicyclopentadiene and a rubber component such as a terminal functional butadiene-acrylonitrile copolymer.
[0022]
  The above vinyl monomer is a reactive monomer and undergoes a crosslinking reaction with the unsaturated group of the above polymer during heat and pressure molding. Examples of the vinyl monomer include, but are not limited to, styrene, vinyl toluene, chlorostyrene, diallyl phthalate, triallyl isocyanurate, and methyl methacrylate. Only one kind of these vinyl monomers may be used, or two or more kinds may be used in combination. Moreover, what is necessary is just to set the usage-amount of a vinyl monomer according to the kind, combination with the said polymer, etc., and it does not specifically limit.
[0023]
  The method for producing the unsaturated polyester is not particularly limited. The combination of the polymer and the vinyl monomer is not particularly limited. That is, the composition of the unsaturated polyester is not particularly limited.
[0024]
  The above vinyl ester resins (epoxy acrylate resins) add vinyl unsaturated carboxylic acids such as acrylic acid and methacrylic acid to the end of epoxy resins such as bisphenol type, novolac type, cycloaliphatic type, and epoxidized polybutadiene type. It is a radical polymerization type resin obtained by dissolving a reaction product obtained by polymerization in a vinyl monomer such as styrene, vinyl toluene, methyl methacrylate, vinyl acetate, chlorostyrene, diallyl phthalate, triallyl isocyanurate or the like.
[0025]
  The method for producing the vinyl ester resin, that is, the method for addition polymerization of a vinyl unsaturated carboxylic acid at the terminal of the epoxy resin is not particularly limited. In addition, the reaction conditions such as reaction temperature and reaction time may be appropriately set according to, for example, the types and combinations of epoxy resins and vinyl unsaturated carboxylic acids, or various physical properties desired for vinyl ester resins and molding materials. Good. In addition, the combination of the epoxy resin, the vinyl unsaturated carboxylic acid, and the vinyl monomer, the amount of use, and the like are not particularly limited. That is, the composition of the vinyl ester resin is not particularly limited.
[0026]
  The (meth) acrylic syrup is a mixture comprising a monomer (meth) acrylic ester, a polymer of the (meth) acrylic ester, and a crosslinking agent. Furthermore, it is a radical polymerization type resin.
[0027]
  Examples of the (meth) acrylic acid ester include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and lauryl (meth) acrylate. , Cyclohexyl (meth) acrylate, glycidyl (meth) acrylate, and the like, but are not particularly limited. Moreover, (meth) acrylamide can also be used. Only one kind of these (meth) acrylic acid esters may be used, or two or more kinds may be used in combination. Of the above-exemplified compounds, methyl methacrylate and (meth) acrylic acid ester having methyl methacrylate as a main component are particularly preferable. By using methyl methacrylate as a main component, various physical properties such as weather resistance, transparency, gloss of the surface, appearance, safety, etc. of molded products formed from molding materials containing (meth) acrylic syrup are further enhanced. Can be improved.
[0028]
  The polymer of the (meth) acrylic acid ester is obtained by polymerizing the (meth) acrylic acid ester. The degree of polymerization of the resulting polymer is not particularly limited. In addition, the monomer component which should become this polymer may contain the vinyl compound other than (meth) acrylic acid ester as needed.
[0029]
  Examples of the crosslinking agent include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Multifunctional (meth) acrylates such as trimethylolpropane tri (meth) acrylate and pentaerythritol tetra (meth) acrylate; divinylbenzene, diallyl phthalate, diallyl isophthalate, triallyl cyanurate, triallyl isocyanurate, etc. It is not particularly limited. Only one kind of these crosslinking agents may be used, or two or more kinds may be used in combination. Moreover, what is necessary is just to set the addition amount of a crosslinking agent according to the combination with a kind, (meth) acrylic acid ester, etc., and it is not specifically limited.
[0030]
  Examples of the vinyl compound include styrene, α-methylstyrene, vinyl toluene, chlorostyrene, vinyl acetate, allyl alcohol, ethylene glycol monoallyl ether, propylene glycol monoallyl ether; acrylic acid, methacrylic acid, crotonic acid, and the like. Unsaturated monocarboxylic acids; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, and monoesters of these unsaturated dicarboxylic acids; styrene, acrylonitrile, maleimides; It is not something. Further, for example, (meth) acrylic polymers having an unsaturated group in the side chain, such as obtained by reacting a (meth) acrylic polymer having a carboxyl group with glycidyl esters of (meth) acrylic acid, etc. It can be used as a vinyl compound. These vinyl compounds may be used alone or in combination of two or more as required. In addition, when (meth) acrylic syrup contains a vinyl compound, the amount of vinyl compound added may be set according to the type, combination with (meth) acrylic acid ester, etc., and is particularly limited. is not.
[0031]
  The method for producing the (meth) acrylic syrup is not particularly limited, and the reaction conditions such as reaction temperature and reaction time are, for example, types and combinations of (meth) acrylic acid ester, crosslinking agent and vinyl compound. Or what is necessary is just to set suitably according to the various physical properties etc. which are desired for (meth) acryl syrup or a molding material. The composition of the (meth) acrylic acid ester, the crosslinking agent and the vinyl compound, and the combination and the amount of use of the (meth) acrylic acid ester, the crosslinking agent and the vinyl compound are not particularly limited. That is, the composition of (meth) acrylic syrup is not particularly limited.
[0032]
  And when said thermosetting resin contains two or more types of radical polymerization type resin chosen from the group which consists of unsaturated polyester, vinyl ester resin, and (meth) acryl syrup, that is, thermosetting resin is these. In the case of the mixture, the mixing ratio is not particularly limited. That is, when the thermosetting resin contains, for example, an unsaturated polyester and a vinyl ester resin, the content of each resin is not particularly limited. Further, the thermosetting resin may contain a radical polymerizable resin other than the above exemplified radical polymerizable resins.
[0033]
  The sulfur-containing antioxidant according to the present invention has the general formula (1)
    R_a-S-CH₂-CH₂-COOR_b    ...... (1)
    (Wherein R_a, R_bEach independently represents an organic residue)
There is no particular limitation as long as it has a structure represented by: As the sulfur-containing antioxidant, specifically, for example,
[0034]
[Chemical 1]

[0035]
[Chemical formula 2]

[0036]
[Chemical Formula 3]

[0037]
[Formula 4]

[0038]
[Chemical formula 5]

[0039]
And thioether-based antioxidants. These sulfur-containing antioxidants may be used alone or in combination of two or more. Of the sulfur-containing antioxidants exemplified above, Compound A and Compound G are more preferred.
[0040]
  The content of the sulfur-containing antioxidant in the thermosetting resin composition is not particularly limited, but a synthetic resin such as a thermosetting resin and a low shrinkage agent (described later) used as necessary. More preferably, the sulfur-containing antioxidant is added in the range of 0.05 to 3.0 parts by weight with respect to 100 parts by weight of the total synthetic resin component containing 0.1 to 1.5 parts by weight. More preferably, it is added within the range of parts by weight. When the addition amount of the sulfur-containing antioxidant is less than 0.05 parts by weight, the effect obtained by adding the sulfur-containing antioxidant may be poor. Moreover, when there is more addition amount of a sulfur-containing antioxidant than 2.0 weight part, there exists a possibility of reducing the various physical properties with which the thermosetting resin is equipped.
[0041]
  As the phosphorus-containing antioxidant according to the present invention, specifically, for example,
[0042]
[Chemical 6]

[0043]
[Chemical 7]

[0044]
[Chemical 8]

[0045]
[Chemical 9]

[0046]
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[0047]
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[0048]
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[0049]
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[0050]
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[0051]
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[0052]
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[0053]
Embedded image

[0054]
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[0055]
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[0056]
Embedded image

[0057]
Embedded image

[0058]
Embedded image

[0059]
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[0060]
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[0061]
Embedded image

[0062]
Embedded image

[0063]
A phosphite-based antioxidant such as bisphenol A pentaerythritol phosphite can be mentioned, but it is not particularly limited. Only one kind of these phosphorus-containing antioxidants may be used in combination with the sulfur-containing antioxidant, or two or more kinds thereof may be used in combination with the sulfur-containing antioxidant. Of the phosphorus-containing antioxidants exemplified above, Compound B, Compound C, Compound D, Compound E, and Compound F are more preferable.
[0064]
  In the case where a sulfur-containing antioxidant and a phosphorus-containing antioxidant are used in combination, the content of the phosphorus-containing antioxidant in the thermosetting resin composition is not particularly limited, but the thermosetting resin, and A phosphorus-containing antioxidant is added within a range of 0.05 to 2.0 parts by weight with respect to 100 parts by weight of a total synthetic resin component including a synthetic resin such as a low shrinkage agent used as necessary. More preferably, it is more preferable to add within the range of 0.1 part by weight to 1.0 part by weight, and particularly preferable to add within the range of 0.2 part by weight to 0.6 part by weight. When the addition amount of the phosphorus-containing antioxidant is less than 0.05 parts by weight, the synergistic effect obtained by using the phosphorus-containing antioxidant in combination becomes poor. Moreover, when there is more addition amount of a phosphorus containing antioxidant than 2.0 weight part, there exists a possibility of reducing the various physical properties with which the thermosetting resin is equipped.
[0065]
  In the case where a sulfur-containing antioxidant and a phosphorus-containing antioxidant are used in combination, the weight ratio between them is not particularly limited. Moreover, the addition method when adding a sulfur-containing antioxidant or a phosphorus-containing antioxidant to a thermosetting resin composition, that is, a thermosetting resin, its timing (timing), etc. are not particularly limited. Absent. That is, the sulfur-containing antioxidant and the phosphorus-containing antioxidant are thermosetting at the time of curing the thermosetting resin composition, specifically, at the time of molding the molding material containing the thermosetting resin composition. What is necessary is just to be contained in the resin composition.
[0066]
  As described above, the thermosetting resin composition according to the present invention includes a thermosetting resin, a sulfur-containing antioxidant having a structure represented by the general formula (1), and, if necessary, a phosphorus-containing antioxidant. An oxidizing agent. Thereby, the thermosetting resin composition excellent in the inhibitory effect with respect to discoloration, such as yellowing when exposed to hot water for a long period of time, can be provided. Moreover, when a sulfur-containing antioxidant and a phosphorus-containing antioxidant are used in combination, a thermosetting resin composition that is more excellent in suppressing the discoloration such as yellowing can be provided by the synergistic effect of both.
[0067]
  In addition, the thermosetting resin composition may further contain a conventionally known phenolic antioxidant as necessary. That is, in the thermosetting resin composition according to the present invention, a sulfur-containing antioxidant and a phenol-based antioxidant can be used in combination, or a sulfur-containing antioxidant, a phosphorus-containing antioxidant, and a phenol-based agent. An antioxidant can be used in combination.
[0068]
  The molding material concerning this invention comprises the thermosetting resin composition of the said structure. Furthermore, the molding material may contain conventionally known auxiliary materials (additives), reinforcing materials, and the like, if necessary. Specific examples of the auxiliary material include a curing agent, a thickening agent, a filler, a low shrinkage agent, an (internal) release agent, a pigment, a viscosity reducing agent, and a coupling agent. The molding material according to the present invention is suitable as, for example, a casting material, SMC (sheet molding compound), BMC (bulk molding compound), and the like.
[0069]
  Examples of the curing agent include benzoyl peroxide, lauroyl peroxide, methyl ethyl ketone peroxide, t-butyl peroxy-2-ethylhexanoate, t-butyl peroxy octoate, t-butyl peroxybenzoate, cumene. Hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, bis (4-t-butylcyclohexyl) peroxydicarbonate, 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, etc. Organic peroxides; radical polymerization initiators such as 2,2′-azobisisobutyronitrile, azo compounds such as 2-phenylazo-2,4-dimethyl-4-methoxyvaleronitrile; Is not to be done. These curing agents may be used alone or in combination of two or more. In addition, the amount of the curing agent to be added may be set according to the type, combination with the thermosetting resin, molding conditions of the molding material, use of the molded product obtained by molding the molding material, or desired physical properties. There is no particular limitation.
[0070]
  Examples of the thickener include polyvalent metal oxides such as magnesium oxide, calcium oxide, and zinc oxide; polyvalent metal hydroxides such as magnesium hydroxide, calcium hydroxide, and aluminum hydroxide; polyfunctional isocyanates; However, it is not particularly limited. These thickeners may be used alone or in combination of two or more. The amount used of the thickener may be set according to the type and combination with the thermosetting resin, the weight average molecular weight and viscosity of the thermosetting resin, the use of the molded product and the desired physical properties, etc. Is not to be done.
[0071]
  Examples of the filler include aluminum hydroxide, calcium carbonate, calcium sulfate, barium sulfate, alumina, clay, talc, milled fiber, silica (silica sand), river sand, diatomaceous earth, mica powder, gypsum, chlorite, and glass powder. Inorganic fillers and organic fillers such as glass spheres and polymer beads may be mentioned, but are not particularly limited. Only one type of these fillers may be used, or two or more types may be used in combination. Further, the blending amount of the filler may be set according to the type and combination with the thermosetting resin, the molding conditions of the molding material, the use of the molded product, the desired physical properties, etc., and is particularly limited. It is not a thing. In addition, what is called transparency can also be provided to a molded article by selecting a filler suitably.
[0072]
  Examples of the low shrinkage agent include polyethylene, polypropylene, polystyrene, three-dimensional crosslinked polystyrene, polymethyl methacrylate, polyethylene glycol, polypropylene glycol, cellulose butyrate, acetate, polyvinyl chloride, polyvinyl acetate, polycaprolactone, Although saturated polyester etc. are mentioned, it is not specifically limited. These low shrinkage agents may be used alone or in combination of two or more. Further, the amount of addition of the low shrinkage agent may be set according to the type and combination with the thermosetting resin, the molding conditions of the molding material, the use of the molded product, the desired physical properties, etc. Is not to be done. By adding a low shrinkage agent, it is possible to further improve the dimensional stability of a molded product obtained by molding a molding material.
[0073]
  Examples of the release agent include stearic acid, zinc stearate, aluminum stearate, calcium stearate, barium stearate, stearic acid amide, lauric acid, triphenyl phosphate, alkyl phosphate, and the like, but are not particularly limited. It is not something. Moreover, generally used release agents such as waxes and silicone oils can also be used. Only one type of these release agents may be used, or two or more types may be used in combination. Further, the addition amount of the release agent may be set according to the type and combination with the thermosetting resin, the molding conditions of the molding material, the use of the molded product, the desired physical properties, etc., and is particularly limited. It is not something.
[0074]
  The pigment is not particularly limited, and inorganic pigments and organic pigments conventionally used for thermosetting resins can be used. The addition amount of the pigment is not particularly limited, and may be appropriately set according to the use of the molded product.
[0075]
  The above-mentioned viscosity reducing agent is not particularly limited, and a viscosity reducing agent conventionally used for thermosetting resins can be used. Moreover, said coupling agent is not specifically limited, The coupling agent conventionally used for the thermosetting resin can be used.
[0076]
  Examples of the reinforcing material include inorganic fibers such as fibers made of glass fiber, carbon fiber, metal fiber, and ceramic; organic fibers made of aramid or polyester; natural fibers, etc., but are not particularly limited. Absent. Examples of the fiber form include roving, chopped strand, mat, and cloth (woven fabric), but are not particularly limited. Only one type of these reinforcing materials may be used, or two or more types may be used in combination. Moreover, the usage-amount of a reinforcing material should just be set according to the combination, the combination with a thermosetting resin, the use of a molded article, a desired physical property, etc., and is not specifically limited.
[0077]
  Moreover, the method of mixing the thermosetting resin composition and the reinforcing material is not particularly limited, and may be appropriately set according to the form of the reinforcing material. For example, when the reinforcing material is in the form of a mat or cloth, the reinforcing material may be impregnated with a thermosetting resin composition. For example, when the form of the reinforcing material is roving or chopped strand, the reinforcing material and the thermosetting resin composition may be kneaded. A molding material containing a reinforcing material is suitable as, for example, SMC or BMC.
[0078]
  The manufacturing method of the molding material concerning this invention, ie, the method of adding the said auxiliary material and a reinforcing material, to a thermosetting resin composition, is not specifically limited. Further, the method for curing the molding material and the curing conditions, that is, the method for producing the molded product are not particularly limited.
[0079]
  As mentioned above, the molding material concerning this invention comprises the thermosetting resin composition of the said structure. The molding material can be applied to various molding methods. Molded products made by molding the above molding materials are excellent in suppressing discoloration such as yellowing when exposed to hot water for a long time, and discoloration due to aging is reduced compared to conventional molded products. Therefore, the aesthetic appearance (appearance) is not impaired and the durability is improved. A molded product formed by molding a molding material is suitable as, for example, artificial marble, and is suitably used in places where hot water or hot water is used, such as a bathtub (bathtub), a wash basin (counter), a sink (sink), etc. .
[0080]
【Example】
  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited at all by these. In the examples and comparative examples, “parts” indicates “parts by weight”.
[0081]
  [Example 1]
  To 88 parts of thermosetting resin composed of 70 parts of unsaturated polyester and 18 parts of vinyl ester resin, 0.5 part of Compound A (trade name ADK STAB AO-23, manufactured by Asahi Denka Kogyo Co., Ltd.) as a sulfur-containing antioxidant Was added and mixed uniformly to prepare a thermosetting resin composition according to the present invention.
[0082]
  The unsaturated polyester is obtained by condensing maleic anhydride, hydrogenated bisphenol A, and propylene glycol using a molar ratio of “1.00: 0.30: 0.75”. The obtained polymer was produced by dissolving in styrene such that the proportion of styrene was 45% by weight. In addition, the above vinyl ester resin is obtained by subjecting a reaction product obtained by addition polymerization using 1.05 mol of methacrylic acid to 1.00 mol (epoxy equivalent) of a bisphenol type epoxy resin as styrene. Was dissolved in the styrene so that the ratio of the amount was 45% by weight.
[0083]
  Next, 1 part of 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane as a curing agent and 150 parts of aluminum hydroxide as a filler are added to the above thermosetting resin composition. Then, 12 parts of three-dimensional crosslinked polystyrene particles as a low shrinkage agent, 0.7 part of magnesium oxide as a thickener, and 4 parts of zinc stearate as a release agent were added and mixed.
[0084]
  Next, the obtained compound was applied to an SMC manufacturing apparatus and impregnated into 60 parts of glass fiber as a reinforcing material, thereby manufacturing SMC as a molding material according to the present invention. The above SMC was heated and pressed under predetermined molding conditions using a mold heated to 110 ° C to 150 ° C. Thereby, a molded product having a thickness of about 4 mm was produced.
[0085]
  In order to evaluate the durability of the obtained molded product, that is, the inhibitory effect on discoloration such as yellowing when exposed to hot water for a long period of time, the following tests were conducted. That is, first, the yellowness (YI) of the molded product was measured using a color difference meter (Nippon Denshoku Industries Co., Ltd., SZ-Σ90). Next, the molded product was immersed in hot water of 98 ° C. for 100 hours, and the yellowness and color difference (ΔE) of the molded product after immersion were measured using the color difference meter. And the difference of the yellowness of the molded product before immersion and the yellowness of the molded product after immersion was calculated | required, and this numerical value was made into yellowing degree ((DELTA) YI). In the above test, the immersion time is 100 hours, for example, when the molded product is a bathtub, when the bathtub is filled with hot water of 40 ° C. to 50 ° C. and used every day for 4 hours, 3 years to 5 years. It corresponds to.
[0086]
  Further, in the same manner as above, after measuring the yellowness and color difference of the molded product after immersing the molded product in hot water at 98 ° C. for 200 hours and after immersing for 300 hours, the degree of yellowing is obtained. It was. The test results, that is, the color difference and the degree of yellowing are summarized in Table 1.
[0087]
  [Comparative Example 1]
  A comparative SMC (Comparative Molding Material) was produced by performing the same operation as in Example 1 except that the compound A was not added to the thermosetting resin. That is, in Example 1, a comparative SMC was produced without using a sulfur-containing antioxidant.
[0088]
  The comparative SMC was subjected to heat and pressure molding under the same molding conditions as the SMC molding conditions of Example 1. This produced a comparative molded product having a thickness of about 4 mm. Next, in the same manner as in Example 1, the color difference and yellowing degree of the obtained comparative molded article were measured. The above color difference and yellowing degree are summarized in Table 1.
[0089]
  [Example 2]
  To 88 parts of thermosetting resin composed of 70 parts of unsaturated polyester and 18 parts of vinyl ester resin, 0.3 part of the above compound A (Adekastab AO-23 manufactured by the same company) as a sulfur-containing antioxidant, and phosphorus-containing antioxidant The thermosetting resin composition according to the present invention was prepared by adding 0.3 part of the compound C (manufactured by Asahi Denka Kogyo Co., Ltd .; trade name ADK STAB PEP-36) as an agent and mixing uniformly. . The composition of the unsaturated polyester and vinyl ester resin is the same as that of the unsaturated polyester and vinyl ester resin used in Example 1.
[0090]
  Next, to the above thermosetting resin composition, 1 part of 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 150 parts of aluminum hydroxide, 12 parts of three-dimensional crosslinked polystyrene particles Then, 0.7 parts of magnesium oxide and 4 parts of zinc stearate were added and mixed.
[0091]
  Next, the obtained compound was applied to an SMC manufacturing apparatus and impregnated into 60 parts of glass fiber as a reinforcing material, thereby manufacturing SMC as a molding material according to the present invention. The above SMC was subjected to heat and pressure molding under the same molding conditions as the SMC molding conditions of Example 1. Thereby, a molded product having a thickness of about 4 mm was produced. Next, in the same manner as in Example 1, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 1.
[0092]
  [Comparative Example 2]
  A comparative SMC (Comparative Molding Material) was produced by performing the same operations as in Example 2 except that the compound A was not added to the thermosetting resin. That is, in Example 2, a comparative SMC was produced without using a sulfur-containing antioxidant.
[0093]
  The comparative SMC was subjected to heat and pressure molding under the same molding conditions as the SMC molding conditions of Example 1. This produced a comparative molded product having a thickness of about 4 mm. Next, in the same manner as in Example 1, the color difference and yellowing degree of the obtained comparative molded article were measured. The above color difference and yellowing degree are summarized in Table 1.
[0094]
[Table 1]

[0095]
  As is clear from the comparison between Example 1 and Comparative Example 1, a molded product formed by molding SMC to which a sulfur-containing antioxidant is added is a comparative SMC to which no sulfur-containing antioxidant is added. It can be seen that the color difference and the yellowing degree change with time are reduced as compared with a comparative molded product formed by molding. That is, it can be seen that a molded product obtained by molding the SMC according to the present invention is excellent in the effect of suppressing discoloration when exposed to hot water for a long time.
[0096]
  Further, as is clear from the comparison between Example 1 and Example 2 and the comparison between Example 2 and Comparative Example 2, SMC to which a sulfur-containing antioxidant and a phosphorus-containing antioxidant are added is used. It can be seen that the molded product formed by molding is further reduced in color change and yellowing due to synergistic effects.
[0097]
  As is clear from the comparison between Comparative Example 1 and Comparative Example 2, the comparative molded product obtained by molding the comparative SMC to which only the phosphorus-containing antioxidant is added has a dipping time of 100 hours. Although the color difference and yellowing change with time are reduced, the color difference and yellowing change with time are prominent when the immersion time exceeds 200 hours. That is, the comparative molded product using only the phosphorus-containing antioxidant has been promoted to discolor more than the comparative molded product without using the phosphorus-containing antioxidant.
[0098]
  Example 3
  According to the present invention, 0.6 parts of the compound A (Adekastab AO-23, manufactured by the same company) as a sulfur-containing antioxidant is added to 100 parts of acrylic syrup as a thermosetting resin and mixed uniformly. A thermosetting resin composition was prepared.
[0099]
  The acrylic syrup uses methyl methacrylate, methacrylic acid, and ethylene glycol dimethacrylate in a weight ratio of “91.7: 3.3: 5.0” and partially polymerizes the methyl methacrylate. It was manufactured by.
[0100]
  Next, to the above thermosetting resin composition, 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane 1 part, aluminum hydroxide 150 parts, magnesium oxide 0.7 parts, And 4 parts of zinc stearate was added and mixed. Thereby, the molding material concerning this invention was manufactured.
[0101]
  The molding material was subjected to heat and pressure molding under predetermined molding conditions using a mold heated to 80 ° C to 130 ° C. Thus, a molded product having a thickness of about 7 mm was manufactured. Next, in the same manner as in Example 1, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 2.
[0102]
  [Comparative Example 3]
  Except not adding the compound A to the thermosetting resin, operations similar to those of Example 3 were performed to produce a comparative molding material. That is, in Example 3, a comparative molding material was produced without using a sulfur-containing antioxidant.
[0103]
  The comparative molding material was subjected to heat and pressure molding under the same molding conditions as the molding material of Example 3. This produced a comparative molded product having a thickness of about 7 mm. Next, in the same manner as in Example 1, the color difference and yellowing degree of the obtained comparative molded article were measured. The above color difference and yellowing degree are summarized in Table 2.
[0104]
  Example 4
  100 parts of acrylic syrup as a thermosetting resin, 0.3 part of the compound A (Adekastab AO-23) manufactured as a sulfur-containing antioxidant, and the compound C (manufactured by the company as a phosphorus-containing antioxidant) -Adeka stub PEP-36) 0.3 part was added and mixed uniformly to prepare a thermosetting resin composition according to the present invention. The composition of the acrylic syrup is the same as that of the acrylic syrup used in Example 3.
[0105]
  Next, to the above thermosetting resin composition, 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane 1 part, aluminum hydroxide 150 parts, magnesium oxide 0.7 parts, And 4 parts of zinc stearate was added and mixed. Thereby, the molding material concerning this invention was manufactured.
[0106]
  The above molding material was subjected to heat and pressure molding under the same molding conditions as the molding material of Example 3. Thus, a molded product having a thickness of about 7 mm was manufactured. Next, in the same manner as in Example 1, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 2.
[0107]
[Table 2]

[0108]
  As is clear from the comparison between Example 3 and Comparative Example 3, a molded product formed by molding a molding material to which a sulfur-containing antioxidant is added is a comparative molding to which no sulfur-containing antioxidant is added. It can be seen that changes over time in color difference and yellowing degree are reduced as compared with a comparative molded product obtained by molding the material. That is, it can be seen that a molded product obtained by molding the molding material according to the present invention is excellent in the effect of suppressing discoloration when exposed to hot water for a long period of time.
[0109]
  Further, as is clear from the comparison between Example 3 and Example 4, a molded product obtained by molding a molding material to which a sulfur-containing antioxidant and a phosphorus-containing antioxidant are added has a synergistic effect of both. Thus, it can be seen that the color difference and the yellowing degree change with time are further reduced.
[0110]
  Example 5
  A sulfur-containing antioxidant is added to a thermosetting resin having the same composition as that of the thermosetting resin used in Example 1, that is, 88 parts of a thermosetting resin composed of 70 parts of unsaturated polyester and 18 parts of vinyl ester resin. 0.23 parts of the compound A (manufactured by Adeka Stub AO-23) and 0.23 parts of the compound F (manufactured by Adeka Stub 1500) as a phosphorus-containing antioxidant are added and mixed uniformly. Thus, a thermosetting resin composition according to the present invention was prepared.
[0111]
  Next, to the above thermosetting resin composition, 1 part of 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 150 parts of aluminum hydroxide, 12 parts of three-dimensional crosslinked polystyrene particles Then, 0.7 parts of magnesium oxide and 4 parts of zinc stearate were added and mixed.
[0112]
  Next, the obtained compound was applied to an SMC manufacturing apparatus and impregnated into 60 parts of glass fiber as a reinforcing material, thereby manufacturing SMC as a molding material according to the present invention. The above SMC was subjected to heat and pressure molding under the same molding conditions as the SMC molding conditions of Example 1. Thereby, a molded product having a thickness of about 4 mm was produced. Next, in the same manner as in Example 1, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 3.
[0113]
  Example 6
  Instead of 0.23 part of compound F, the same operation as in Example 5 and heating and pressing, etc., except that 0.23 part of compound E (manufactured by Adeka Stub 260) as a phosphorus-containing antioxidant was added. A molded product having a thickness of about 4 mm was manufactured by performing the operation and heating and pressing. Next, in the same manner as in Example 5, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 3.
[0114]
  Example 7
  In place of 0.23 part of Compound F, the operation of Example 5 and heating and pressing, etc., except that 0.23 part of Compound B (manufactured by Adeka Stub PEP-24G) as a phosphorus-containing antioxidant was added. The same operation and heat and pressure molding were performed to produce a molded product having a thickness of about 4 mm. Next, in the same manner as in Example 5, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 3.
[0115]
  [Comparative Example 4]
  Except that the compound A and the compound F are not added to the thermosetting resin, the same operation as in Example 5 and the heat-pressure molding, etc., the heat-pressure molding, etc. are performed, and the thickness is about 4 mm. A molded product was produced. That is, in Example 5, a comparative molded article was produced without using a sulfur-containing antioxidant and a phosphorus-containing antioxidant. Next, in the same manner as in Example 5, the color difference and the yellowing degree of the obtained comparative molded article were measured. The above color difference and yellowing degree are summarized in Table 3.
[0116]
[Table 3]

[0117]
  As is clear from the comparison between Examples 5 to 7 and Comparative Example 4, a molded product formed by molding SMC to which a sulfur-containing antioxidant and a phosphorus-containing antioxidant are added is a sulfur-containing antioxidant. It can be seen that color change and yellowing change over time are reduced as compared with a comparative molded product obtained by molding a comparative SMC to which no phosphorous-containing antioxidant is added. That is, it can be seen that a molded product obtained by molding the SMC according to the present invention is excellent in the effect of suppressing discoloration when exposed to hot water for a long time.
[0118]
  Example 8
  A sulfur-containing antioxidant is added to a thermosetting resin having the same composition as that of the thermosetting resin used in Example 1, that is, 88 parts of a thermosetting resin composed of 70 parts of unsaturated polyester and 18 parts of vinyl ester resin. The thermosetting resin composition according to the present invention was prepared by adding 0.3 part of the above-mentioned compound G (manufactured by Adeka Stub AO-412S) as a uniform mixture.
[0119]
  Next, to the above thermosetting resin composition, 1 part of 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 150 parts of aluminum hydroxide, 12 parts of three-dimensional crosslinked polystyrene particles Then, 0.7 parts of magnesium oxide and 4 parts of zinc stearate were added and mixed.
[0120]
  Next, the obtained compound was applied to an SMC manufacturing apparatus and impregnated into 60 parts of glass fiber as a reinforcing material, thereby manufacturing SMC as a molding material according to the present invention. The above SMC was subjected to heat and pressure molding under the same molding conditions as the SMC molding conditions of Example 1. Thereby, a molded product having a thickness of about 4 mm was produced. Subsequently, the color difference and yellowing degree of the obtained molded product were measured in the same manner as in Example 1 except that the temperature of hot water in which the molded product was immersed was changed from 98 ° C. to 90 ° C. The above color difference and yellowing degree are summarized in Table 4.
[0121]
  Example 9
  Except that the amount of compound G added was changed from 0.3 part to 0.5 part, the same operation as in Example 8 and heating and pressing, etc. and heating and pressing were performed, and the thickness was about 4 mm. The molded article was manufactured. Next, in the same manner as in Example 8, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 4.
[0122]
  Example 10
  Except that the amount of compound G added was changed from 0.3 part to 0.8 part, the same operation as in Example 8 and the heat and pressure molding and the like were performed, and the thickness was about 4 mm. The molded article was manufactured. Next, in the same manner as in Example 8, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 4.
[0123]
  Example 11
  In a thermosetting resin, 0.3 part of the compound G (manufactured by Adeka Stub AO-412S) as a sulfur-containing antioxidant and the compound F (manufactured by Adeka Stub 1500) as a phosphorus-containing antioxidant Except for the addition of 3 parts, the same operation as in Example 8 and the same heat pressure molding and the like, and heat pressure molding were performed to produce a molded product having a thickness of about 4 mm. Next, in the same manner as in Example 8, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 4.
[0124]
  Example 12
  In a thermosetting resin, 0.3 part of the compound G (manufactured by Adeka Stub AO-412S) as a sulfur-containing antioxidant and the compound E (manufactured by Adeka Stub 260) as a phosphorus-containing antioxidant Except for the addition of 3 parts, the same operation as in Example 8 and the same heat pressure molding and the like, and heat pressure molding were performed to produce a molded product having a thickness of about 4 mm. Next, in the same manner as in Example 8, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 4.
[0125]
  Example 13
  In a thermosetting resin, 0.3 part of the compound G (manufactured by Adeka Stub AO-412S) as a sulfur-containing antioxidant, and the compound C (manufactured by Adeka Stub PEP-36 as a phosphorus-containing antioxidant) Except for the addition of 0.3 part, the same operation as in Example 8, heat pressure molding, etc., heat pressure molding, etc. were performed to produce a molded product having a thickness of about 4 mm. Next, in the same manner as in Example 8, the color difference and the yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 4.
[0126]
  [Comparative Example 5]
  Except for not adding the compound G to the thermosetting resin, the same operation as in Example 8 and heating and pressing, etc. and heating and pressing are performed to obtain a comparative molded product having a thickness of about 4 mm. Manufactured. That is, in Example 8, a comparative molded product was produced without using a sulfur-containing antioxidant. Next, in the same manner as in Example 8, the color difference and yellowing degree of the obtained comparative molded article were measured. The above color difference and yellowing degree are summarized in Table 4.
[0127]
[Table 4]

[0128]
  As is clear from the comparison between Examples 8 to 10 and Comparative Example 5, the molded product formed by molding SMC to which the sulfur-containing antioxidant is added is a comparative product to which no sulfur-containing antioxidant is added. It can be seen that changes over time in color difference and yellowing degree are reduced as compared with a comparative molded product formed by molding SMC. That is, it can be seen that a molded product obtained by molding the SMC according to the present invention is excellent in the effect of suppressing discoloration when exposed to hot water for a long time.
[0129]
  Further, as is clear from the comparison between Example 8 and Examples 11 to 13, a molded article formed by molding a molding material to which a sulfur-containing antioxidant and a phosphorus-containing antioxidant are added is It can be seen that the color difference and the yellowing change with time are further reduced by the synergistic effect.
[0130]
  Example 14
  By adding 0.5 parts of the compound A (Adeka Stub AO-23) as a sulfur-containing antioxidant to 88 parts of the unsaturated polyester as a thermosetting resin, and uniformly mixing, Such a thermosetting resin composition was prepared. The composition of the unsaturated polyester is the same as that of the unsaturated polyester used in Example 1.
[0131]
  Next, to the above thermosetting resin composition, 1 part of 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 150 parts of aluminum hydroxide, 12 parts of three-dimensional crosslinked polystyrene particles Then, 0.7 parts of magnesium oxide and 4 parts of zinc stearate were added and mixed.
[0132]
  Next, the obtained compound was applied to an SMC manufacturing apparatus and impregnated into 60 parts of glass fiber as a reinforcing material, thereby manufacturing SMC as a molding material according to the present invention. The above SMC was subjected to heat and pressure molding under the same molding conditions as the SMC molding conditions of Example 1. Thereby, a molded product having a thickness of about 4 mm was produced. Subsequently, the color difference and yellowing degree of the obtained molded product were measured in the same manner as in Example 1 except that the temperature of hot water in which the molded product was immersed was changed from 98 ° C. to 90 ° C. The above color difference and yellowing degree are summarized in Table 5.
[0133]
  Example 15
  In a thermosetting resin, 0.3 part of the compound A (manufactured by Adeka Stub AO-23) as a sulfur-containing antioxidant, and the compound C (manufactured by Adeka Stub PEP-36 by the company) as a phosphorus-containing antioxidant. Except for the addition of 0.3 part, the same operation as in Example 14, heat pressure molding, and the like, and heat pressure molding were performed to produce a molded product having a thickness of about 4 mm. Next, in the same manner as in Example 14, the color difference and yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 5.
[0134]
  [Comparative Example 6]
  Except that the compound A is not added to the thermosetting resin, the same operation as in Example 14 and the heat and pressure molding and the like and the heat and pressure molding are performed to obtain a comparative molded product having a thickness of about 4 mm. Manufactured. That is, in Example 14, a comparative molded product was produced without using a sulfur-containing antioxidant. Next, in the same manner as in Example 14, the color difference and yellowing degree of the obtained comparative molded article were measured. The above color difference and yellowing degree are summarized in Table 5.
[0135]
  Example 16
  In place of 88 parts of unsaturated polyester, the operation of Example 14 and heating and pressing, etc., except that 88 parts of thermosetting resin consisting of 79.2 parts of unsaturated polyester and 8.8 parts of vinyl ester resin were used. The same operation and heat and pressure molding were performed to produce a molded product having a thickness of about 4 mm. The composition of the unsaturated polyester and vinyl ester resin is the same as that of the unsaturated polyester and vinyl ester resin used in Example 1.
[0136]
  Next, in the same manner as in Example 14, the color difference and yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 5.
[0137]
  Example 17
  Except for using 88 parts of the unsaturated polyester, 88 parts of the thermosetting resin used in Example 16 were used, and the same operations as those of Example 15 and heating and pressing, etc., and heating and pressing were performed. Thus, a molded product having a thickness of about 4 mm was manufactured. Next, in the same manner as in Example 14, the color difference and yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 5.
[0138]
  [Comparative Example 7]
  Except for using 88 parts of the thermosetting resin used in Example 16 instead of 88 parts of the unsaturated polyester, the same operation as that of Comparative Example 6 and heating and pressing, and the like were performed. Thus, a comparative molded product having a thickness of about 4 mm was manufactured. That is, in Example 16, a comparative molded product was produced without using a sulfur-containing antioxidant. Subsequently, in the same manner as in Example 14, the color difference and the yellowing degree of the obtained comparative molded article were measured. The above color difference and yellowing degree are summarized in Table 5.
[0139]
  Example 18
  In place of 88 parts of unsaturated polyester, except that 88 parts of thermosetting resin consisting of 61.6 parts of unsaturated polyester and 26.4 parts of vinyl ester resin was used, the operation of Example 14 and heating and pressure molding, etc. The same operation and heat and pressure molding were performed to produce a molded product having a thickness of about 4 mm. The composition of the unsaturated polyester and vinyl ester resin is the same as that of the unsaturated polyester and vinyl ester resin used in Example 1.
[0140]
  Subsequently, the color difference and yellowing degree of the obtained molded product were measured in the same manner as in Example 14. The above color difference and yellowing degree are summarized in Table 5.
[0141]
  Example 19
  Except for using 88 parts of the unsaturated polyester, 88 parts of the thermosetting resin used in Example 18 were used, and the same operations as those of Example 15 and heating and pressing, etc. and heating and pressing were performed. Thus, a molded product having a thickness of about 4 mm was manufactured. Next, in the same manner as in Example 14, the color difference and yellowing degree of the obtained molded product were measured. The above color difference and yellowing degree are summarized in Table 5.
[0142]
  [Comparative Example 8]
  Except for using 88 parts of the thermosetting resin used in Example 18 instead of 88 parts of the unsaturated polyester, the same operation as that of Comparative Example 6 and the heat and pressure molding and the like and the heat and pressure molding are performed. Thus, a comparative molded product having a thickness of about 4 mm was manufactured. That is, in Example 18, a comparative molded product was produced without using a sulfur-containing antioxidant. Subsequently, in the same manner as in Example 14, the color difference and the yellowing degree of the obtained comparative molded article were measured. The above color difference and yellowing degree are summarized in Table 5.
[0143]
[Table 5]

[0144]
  As is clear from the comparison between Examples 14 and 15 and Comparative Example 6, the comparison between Examples 16 and 17 and Comparative Example 7, and the comparison between Examples 18 and 19 and Comparative Example 8, sulfur-containing antioxidants The molded product formed by molding SMC to which the additive is added has a color difference and a yellowing degree over time as compared with a comparative molded product formed by molding a comparative SMC to which no sulfur-containing antioxidant is added. It can be seen that the change is reduced. That is, it can be seen that a molded product obtained by molding the SMC according to the present invention is excellent in the effect of suppressing discoloration when exposed to hot water for a long time.
[0145]
  As is apparent from the results of Examples 1 to 19, the molding material according to the present invention is excellent in the effect of suppressing discoloration such as yellowing when exposed to hot water for a long time. When a molded product such as a bathtub is manufactured using the material, the color of the molded product due to change with time is reduced as compared with a conventional molded product. Therefore, the molded article does not impair the aesthetic appearance (appearance), so that the durability is improved.
[0146]
【The invention's effect】
  The thermosetting resin composition of the present invention isAs aboveAt least one radical polymerization resin selected from the group consisting of unsaturated polyester, vinyl ester resin, and (meth) acrylic syrup;General formula (1)
    R_a-S-CH₂-CH₂-COOR_b    ...... (1)
    (Wherein R_a, R_bEach independently represents an organic residue)
Sulfur-containing antioxidant represented byWhenIt is the structure containing.
[0147]
  ThisIncluding a predetermined thermosetting resin,There is an effect that it is possible to provide a thermosetting resin composition excellent in the effect of suppressing discoloration such as yellowing when exposed to hot water for a long period of time.
[0148]
  Moreover, the thermosetting resin composition of the present invention comprises:As aboveUnsaturated polyester, vinyl ester resin, and general formula (1)
R _a -S-CH ₂ -CH ₂ -COOR _b ...... (1)
(Wherein R _a , R _b Each independently represents an organic residue)
A sulfur-containing antioxidant represented byIt is the composition which includes.
[0149]
  ThisThere is an effect that it is possible to provide a thermosetting resin composition that contains a predetermined thermosetting resin and is excellent in the effect of suppressing discoloration such as yellowing when exposed to hot water for a long period of time.
[0150]
  As described above, the thermosetting resin composition of the present invention preferably includes a phosphorus-containing antioxidant.
[0151]
  As a result, a synergistic effect of the sulfur-containing antioxidant and the phosphorus-containing antioxidant provides a thermosetting resin composition that is more excellent in suppressing the discoloration such as yellowing when exposed to hot water for a long time. There is an effect that can be done.
[0152]
  As described above, the molding material of the present invention preferably has a configuration including the thermosetting resin composition of the present invention.
[0153]
  Thereby, it is possible to provide a more excellent molding material due to the effect of suppressing discoloration such as yellowing when exposed to hot water for a long period of time. For example, when a molded product such as a bathtub is manufactured using the molding material, the color change due to aging of the molded product is reduced as compared with a conventional molded product. There is an effect that the property is improved.

Claims (6)

At least one radical polymerization resin selected from the group consisting of unsaturated polyester, vinyl ester resin, and (meth) acrylic syrup;
General formula (1)
R _a —S—CH ₂ —CH ₂ —COOR _b (1)
(Wherein R _a and R _b each independently represents an organic residue)
The thermosetting resin composition which comprises a sulfur-containing antioxidant represented in. With unsaturated polyester;
Vinyl ester resin,
General formula (1)
R _a -S-CH ₂ -CH ₂ -COOR _b     ...... (1)
(Wherein R _a , R _b Each independently represents an organic residue)
The thermosetting resin composition characterized by including the sulfur-containing antioxidant represented by these. The thermosetting resin composition according to claim 1 , further comprising a phosphorus-containing antioxidant. A molding material comprising the thermosetting resin composition according to any one of claims 1 to 3 . The molding material according to claim 4 , wherein the molding material is used for a bathtub, a wash basin or a sink. An artificial marble comprising the molding material according to claim 4 .