JP2004002786A - Polyurethane resin as slush casting material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sluch casting material that has improved melt-flow properties in slush casting and has an excellent heat resistance. <P>SOLUTION: As a slush-casting material, is used a thermoplastic polyurethane resin (A) having a temperature difference of 0-30°C between the softening start and the softening completion according to the thermomechanical analysis penetration method and has a softening start temperature of 135-200°C.The resin (A) includes 5-50 wt.% of the hard segment comprising the number-average molecular weight of 200-2,000 constituted with a diisocyanate having a symmetric structure, a low-molecular diamine having a symmetrical structure and/or a low-molecular diol and the soft segment constituted with a polymeric diol having a number-averaged molecular weight of 500-5,000 in which the content of aromatic rings is ≤ 35wt.% and the aromatic ring content (x) and the urea group content (y) satisfy 0.1x+2.5 ≤ y ≤ -0.1x+6. <P>COPYRIGHT: (C)2004,JPO

Description

【００２３】
式中、Ｚは直接結合、炭素数１〜６のアルキレン基、炭素数２〜６のアルキリデン基、シクロアルキリデン基、アリールアルキリデン基、Ｏ、ＳＯ、ＳＯ_２、ＣＯ、Ｓ、ＣＦ_２、Ｃ（ＣＦ_３）_２又はＮＨを示す。
【００２４】
上記（ａ３’１）としては、例えば、炭素数２〜１８の直鎖アルキレンジオール、例えばエチレングリコール、１，４−ブタンジオール（以下ＢＧと略記する）、１，６−ヘキサンジオール（以下ＨＧと略記）、１，８−オクタンジオール、１，１２−ドデカンジオール；炭素数４〜１５の脂環式ジオール、例えば１，４−ビス（ヒドロキシメチル）シクロヘキサン、１，４−シクロヘキサンジオール；炭素数８〜１５の芳香脂肪族ジオール、例えばｐ−キシリレングリコール等が挙げられる。
【００２５】
上記（ａ３’２）としては、例えば、ハイドロキノンのＥＯ（２〜６モル）付加物、ビスフェノールＡのＥＯ（２〜６モル）付加物、ビスフェノールＦのＥＯ（２〜６モル）付加物及びビスフェノールＳのＥＯ（２〜６モル）付加物等が挙げられる。
【００２６】
上記（ａ３’３）としては、例えば、ハイドロキノンのＴＨＦ（２〜４モル）付加物、ビスフェノールＡのＴＨＦ（２〜４モル）付加物、ビスフェノールＦのＴＨＦ（２〜４モル）付加物及びビスフェノールＳのＴＨＦ（２〜４モル）付加物等が挙げられる。
【００２７】
上記（ａ３’４）としては、例えば、ジエチレングリコール、トリエチレングリコール等が挙げられる。
上記（ａ３’５）としては、例えば、ネオペンチルグリコール等が挙げられる。
【００２８】
上記（ａ３’）として好ましいものは、エチレングリコール、１，４−ブタンジオール、１，６−ヘキサンジオール、１，４−ビス（ヒドロキシメチル）シクロヘキサン及び１，４−シクロヘキサンジオールであり、特に好ましいものは１，４−ブタンジオール、１，６−ヘキサンジオール及び１，４−ビス（ヒドロキシメチル）シクロヘキサンである。
【００２９】
上記（ａ２）と上記（ａ３）は、それぞれ単独で用いることもできるが、（ａ２）と（ａ３）を併用するのが好ましく、そのモル比は（ａ２）／（ａ３）＝０．５〜１０、とくに１〜５が好ましい。
【００３０】
本発明において、上記（ａ１）、上記（ａ２）及び／または上記（ａ３）から構成されるハードセグメント（Ａ１）の数平均分子量（以下Ｍｎと略記）は、好ましくは２００〜２０００、さらに好ましくは３００〜１０００である。シャープメルト性の観点から２００以上が好ましく、ＳＴｉの観点から２０００以下が好ましい。ハードセグメント（Ａ１）のＭｎは、下記計算式（ｉｉ）から求めることができる。
［（ａ１）の重量＋（ａ２）の重量＋（ａ３）の重量］／［（ａ１）のモル数−（ａ２）のモル数−（ａ３）のモル数］　（ｉｉ）
【００３１】
また上記（Ａ）中のハードセグメント（Ａ１）［（ａ１）＋（ａ２）＋（ａ３）の合計］の含有量は、表皮の耐熱性の観点から５重量％以上が好ましく、ＳＴｉの観点から５０重量％以下が好ましい。さらに好ましくは８〜４０重量％、特に好ましくは１０〜３０重量％である。
【００３２】
４．高分子ジオール（ａ４）
以下、ソフトセグメント（Ａ２）を構成する高分子ジオール（ａ４）を説明する。高分子ジオール（ａ４）は、好ましくは５００〜５，０００、より好ましくは７００〜３，０００のＭｎを有し、好ましくは重量平均分子量（以下Ｍｗと略記）／Ｍｎの比が１．０〜３．０、特に好ましくは１．０〜２．０の比を有する。Ｍｎは、風合いとＳＴｉの観点から５００以上が好ましく、シャープメルト性の観点から５０００以下が好ましい。（ａ４）のＭｗ及びＭｎは、溶媒としてテトラヒドロフランを用いるゲルパーミエーションクロマトグラフィー（以下ＧＰＣと略記）法で測定される。
【００３３】
上記（ａ４）としては、例えば、ポリエーテルジオール、ポリエステルジオール、ポリシロキサングリコール、ポリブタジエングリコール、アクリルジオール、ポリマージオール（高分子量のジオール中でビニル単量体を重合してなるジオール）及びこれら２種以上の混合物等が挙げられる。これらのうち好ましくは、ポリエーテルジオール及びポリエステルジオールである。以下説明する。
【００３４】
ポリエーテルジオール
ポリエーテルジオールとしては、例えば、２個の活性水素原子を有する化合物（２価アルコール、２価フェノール、１級モノアミン等）にアルキレンオキサイド（以下ＡＯと略記）が付加した構造の化合物及びそれらの混合物等が挙げられる。
【００３５】
上記２価アルコールとしては、例えば、エチレングリコール、ジエチレングリコール、プロピレングリコール、１，３−及び１，４−ブタンジオール、１，６−ヘキサンジオール、ネオペンチルグリコール等のアルキレングリコール、環状基を有するジオール（例えば、特公昭４５−１４７４号公報に記載のもの）等が挙げられる。また、２価フェノールとしてはピロガロール、ハイドロキノン、フロログルシン等の単環多価フェノール；ビスフェノールＡ、ビスフェノールＳ、ビスフェノールＦ等のビスフェノール類等が挙げられる。
上記２個の活性水素原子を有する化合物として好ましいものは２価アルコール、特に１，４−ブタンジオールである。
【００３６】
ＡＯとしては、例えば、炭素数２〜８のＡＯ及び置換ＡＯ、例えばＥＯ、プロピレンオキサイド（以下ＰＯと略記）、１，２−、１，３−、及び２，３−ブチレンオキサイド、ＴＨＦ、スチレンオキサイド及びこれらの２種以上の併用（ブロックまたはランダム付加）等が挙げられる。これらのうち好ましいものはＰＯ単独及びＥＯとＰＯの併用である。
【００３７】
ポリエステルジオール
ポリエステルジオールとしては、例えば、▲１▼縮合ポリエステルジオール、▲２▼ポリラクトンジオール、▲３▼ポリカーボネートジオール、及びこれらの２種以上の併用が挙げられる。
上記▲１▼は例えばジオール（低分子ジオール及び／又はポリエーテルジオール等）の１種以上とジカルボン酸もしくはそのエステル形成性誘導体［低級アルキル（炭素数１〜４）エステル、酸無水物、ハライド（クロライド等）等］との縮合重合、又は、ジオールとジカルボン酸無水物及びＡＯとの反応により製造することができる。
上記▲２▼は上記ジオールの１種以上を開始剤としてラクトンを開環重合して得られる。
上記▲３▼は上記ジオールとアルキレンカーボネート（エチレンカーボネート）との反応により製造することができる。
【００３８】
上記▲１▼、▲２▼及び▲３▼のための原料ジオールのうち低分子ジオールとしては、例えば、脂肪族低分子ジオール類（エチレングリコール、ジエチレングリコール、プロピレングリコール、１，４−ブタンジオール、１，６−ヘキサンジオール等）；環状基を有する低分子ジオール類［例えば特公昭４５−１４７４号公報に記載のもの：１，４−ビス（ヒドロキシメチル）シクロヘキサン、ｍ−またはｐ−キシリレングリコール等］；ビスフェノール類のアルキレンオキサイド低モル付加物（分子量５００未満）；及びこれらの２種以上の併用等を挙げることができ、ポリエーテルジオールとしては、例えば、先に説明したポリエーテルジオールの１種以上等を挙げることができる。好ましいのは１，４−ブタンジオール及び１，６−ヘキサンジオールである。
【００３９】
上記▲１▼のための原料ジカルボン酸としては、例えば、炭素数２〜１０の脂肪族ジカルボン酸（コハク酸、アジピン酸、セバシン酸、グルタル酸、アゼライン酸、マレイン酸、フマル酸等）、炭素数８〜１２の芳香族ジカルボン酸（テレフタル酸、イソフタル酸等）及びこれらの２種以上の併用等が挙げられる。
【００４０】
上記▲１▼の好ましい例としては、例えば、ポリブチレンアジペートジオール及びポリヘキサメチレンイソフタレートジオール（以下、それぞれＰＢＡ及びＰＨＩＰと略記）ならびにこれらの併用等を挙げることができる。
【００４１】
上記▲２▼のための原料ラクトンとしては、例えば、γ−ブチロラクトン、γ−バレロラクトン、ε−カプロラクトン及びこれらの２種以上の併用等が挙げられる。
【００４２】
上記（Ａ）中の芳香環含量ｘは３５重量％以下が好ましく、ウレア基含量（重量％）ｙが以下の関係式（ｉ）を満たす範囲であることが好ましい。すなわち、溶融性の観点からｙが−０．１ｘ＋６を越えないことが好ましく、耐熱性の観点からｙが少なくとも−０．１ｘ＋２．５であることが好ましく、低温特性の観点からｘが３５重量％以下であることが好ましい。
−０．１ｘ＋２．５≦ｙ≦−０．１ｘ＋６　　　　（ｉ）
さらに、以下の式（ｉ’’）を満たしｘが１〜３０重量％であることが好ましく、
−０．１ｘ＋２．５≦ｙ≦−０．１ｘ＋５．５　　（ｉ’’）
特に、以下の式（ｉ’’’）を満たしｘが２〜３０重量％であることが好ましく、
−０．１ｘ＋２．５≦ｙ≦−０．１ｘ＋５．５　　（ｉ’’’）
耐摩耗性の観点から、以下の式（ｉ’）を満たしｘが５〜２５重量％であることが最も好ましい。
−０．１ｘ＋３≦ｙ≦−０．１ｘ＋５　　　　　　（ｉ’）
本明細書中、芳香環含量とは（Ａ）中の芳香環部分の含量のことである。また、ウレア基含量とは（Ａ）中の−ＮＨＣＯＮＨ−基の含量のことである。
【００４３】
本発明における熱可塑性ポリウレタン樹脂（Ａ）のＭｎは、樹脂強度の観点から４０００以上が好ましく、ＳＴｉの観点から４００００以下が好ましい。さらに好ましくは８０００〜２５０００である。
Ｍｎは、溶媒にＮ，Ｎ−ジメチルフォルムアミド（以下ＤＭＦと略記）を用いるＧＰＣ法で測定される。
【００４４】
上記（Ａ）は上記（ａ１）と活性水素含有成分［上記（ａ２）及び／又は上記（ａ３）、及び上記（ａ４）及び必要により重合停止剤（ａ５）］を一段で反応させるワンショット法；ジオール［上記（ａ４）及び必要により上記（ａ３）］ならびに必要により（ａ５）と過剰の（ａ１）を反応させてＮＣＯ末端ウレタンプレポリマー（以下Ｕｐと略記）を形成し、Ｕｐと残りの活性水素含有成分［（ａ２）及び／又は（ａ３）、及び必要により（ａ５）］を反応させるプレポリマー法のいずれで製造してもよい。好ましいのはプレポリマー法である。
【００４５】
上記（Ａ）は粉体として得ることが好ましい。（Ａ）の粉体を得る方法としては、▲１▼上記方法で得られたブロック状またはペレット状の（Ａ）を冷凍粉砕法、氷結粉砕法等の方法で粉砕し、（Ａ）の粉体を得る方法；▲２▼無溶剤下または溶剤の存在下で上記（ａ４）及び必要により上記（ａ３）及び／又は上記（ａ５）と過剰の上記（ａ１）を反応させて得られたＵｐを、分散安定剤を含む水中に高速撹拌機を用いて分散し、水及び／または（ａ２）と必要により（ａ５）とを反応させる方法；▲３▼無溶剤下または溶剤の存在下で▲２▼と同様にして得られたＵｐを、分散安定剤を含む非水系分散媒（ヘキサン、ヘプタン等）中に分散し、（ａ２）と必要により（ａ５）を反応させる方法等が挙げられる。これら▲１▼〜▲３▼の方法において、（ａ５）はプレポリマー製造時、又はウレタン樹脂製造時のいずれの時に添加してもよい。これらの方法のうち特に好ましい製造方法は▲２▼の方法である。
【００４６】
上記▲２▼及び▲３▼の方法において、Ｕｐ、上記（ａ２）及び必要により上記（ａ５）の混合体（Ｍ）１００重量部に対する、分散安定剤と水又は非水系分散媒とからなる分散安定剤液の量は、（Ｍ）の分散状態、得られる樹脂粉末の粒度の観点から５０重量部以上が好ましく、さらに好ましくは１００〜１０００重量部である。また必要により混合体（Ｍ）を低粘度化するために加温（例えば４０〜１００℃）してもよく、また、エステル系溶剤、ケトン系溶剤、塩素系溶剤、芳香族溶剤等のイソシアネートに不活性な有機溶剤を添加してもよい。高速分散機の回転数は好ましくは少なくとも１０００ｒｐｍ、さらに好ましくは３０００〜１００００ｒｐｍである。
【００４７】
この場合において上記（ａ２）及び必要により上記（ａ５）は、Ｕｐを水中に分散させた後に添加してもよく、またＵｐの分散直前に添加してもよいが、反応がより均一に行われる点で後者の方が好ましい。
【００４８】
上記（ａ５）としては、例えば、炭素数１〜１２の１価のアルコール（メタノール、エタノール、ｎ−ブタノール、ｎ−オクタノール、２−エチルヘキサノール、セロソルブ、フェノールのアルキレンオキサイド付加物等）及び炭素数１〜１２のモノアミン［ジエチルアミン、ジブチルアミン（以下ＤＢＡと略記）、ジエタノールアミン等］等が挙げられ、これらのうち１価のアルコールが好ましく、ｎ−オクタノール、２−エチルヘキサノールが特に好ましい。
【００４９】
ウレタン化反応において、必要により公知の触媒を使用できる。該触媒の具体例としては、例えば、有機金属化合物［スズ系触媒、例えば、ジブチルスズジラウレート、ジオクチルスズジラウレート、スタナスオクテート等；鉛系触媒、例えば、オクテン酸鉛等］；アミン類［トリエチルアミン、トリエチレンジアミン、ジアザビシクロウンデセン（サンアプロ（株）製，ＤＢＵ）等］；及びこれらの２種以上の併用等が挙げられる。触媒の使用量は特に限定はないが上記（Ａ）１００重量部当り、０．００１〜０．０５重量部が好ましい。
また、ウレタン化反応において、必要により公知の溶剤（ＴＨＦ、ＤＭＦ、トルエン、ＭＥＫ等）を使用できる。
【００５０】
本発明の成形用材料は、上記（Ａ）のみでもよく、可塑剤（Ｂ）を更に含んでいてもよく、また、必要により（Ａ）に、又は（Ａ）及び（Ｂ）に、更に添加剤（Ｃ）を含んでいてもよい。
上記（Ｂ）としては、例えば、リン酸エステル；ポリ（重合度３〜１０）アルキレン（炭素数２〜３）グリコールの芳香族モノカルボン酸ジエステル；フタル酸エステル［フタル酸ジブチル、フタル酸ジオクチル、フタル酸ジブチルベンジル、フタル酸ジイソデシル等］；脂肪族ジカルボン酸エステル［アジピン酸ジ−２−エチルヘキシル、セバシン酸−２−エチルヘキシル等］；トリメリット酸エステル［トリメリット酸トリ−２−エチルヘキシル、トリメリット酸トリオクチル等］；及び脂肪酸エステル［オレイン酸ブチル等］；ならびにこれらの２種以上の混合物等が挙げられる。
【００５１】
上記（Ｂ）として好ましいものは、耐吸湿性の観点からリン酸エステルであり、特に下記一般式（４）で示されるリン酸エステル（Ｂ１）であり、また、低温特性、特に低温でのエアバッグドアの開裂性の観点から、下記一般式（７）で示されるポリ（重合度３〜１０）アルキレン（炭素数２〜３）グリコールの芳香族モノカルボン酸ジエステル（Ｂ２）である。
【００５２】
【化３】

【００５３】
式中、Ｒは、それぞれ独立に、ハロゲンで置換されていてもよい炭素数１〜１０の１価の炭化水素基であり、複数個のＲは同一でも異なっていてもよい。Ｒ’はハロゲンで置換されていてもよい炭素数２〜１５の２価の有機基を表し、ｑは１〜６の整数を表す。
【００５４】
Ｒとしては、例えば、炭素数１〜１０の脂肪族炭化水素基（メチル基、エチル基、イソプロピル基、ｎ−ブチル基、ｔ−ブチル基、ヘキシル基等）、炭素数１〜４のアルキル基で置換されていてもよい芳香族炭化水素基（フェニル基、キシレニル基、クレジル基、エチルベンジル基、ブチルベンジル基等）及びこれらのハロゲン置換された基等が挙げられる。好ましくはフェニル基、アルキルフェニル基、又はハロゲン置換フェニル基である。
【００５５】
Ｒ’としては、例えば、炭素数２〜１５の２価の脂肪族炭化水素基（エチレン基、プロピレン基、ｎ−ブチレン基、ｔ−ブチレン基、ヘキシレン基等）、炭素数６〜１５の硫黄又は酸素原子を含んでもよい２価の芳香族炭化水素基［フェニレン基、ビフェニレン基、−Ｐｈ−ＣＨ_２−Ｐｈ−、−Ｐｈ−Ｃ（ＣＨ_３）_２−Ｐｈ−、−Ｐｈ−ＳＯ−Ｐｈ−（Ｐｈはフェニレン基を示す）、ビスフェノール類（ビスフェノールＡ、ビスフェノールＦ、ビスフェノールＳ等）の水酸基を除いた残基等］及びこれらのハロゲン置換された基等が挙げられる。
好ましいのは、炭素数６〜１５の硫黄又は酸素原子を含んでもよい２価の芳香族炭化水素基である。
【００５６】
上記（Ｂ１）として例示したもののうち、特に好ましいものは一般式（４）におけるＲがフェニル基、アルキルフェニル基、又はハロゲン置換フェニル基であり、Ｒ’が下記一般式（５）である可塑剤（Ｂ２）である。
−Ｐｈ’−（Ａ−Ｐｈ’）ｐ−　　　　　　　（５）
式中、Ｐｈ’は１，４−フェニレン基、ｐは０又は１，Ａは直接結合、メチレン基、イソプロピリデン基又はＳＯを表す。
【００５７】
上記（Ｂ２）としては、下記一般式（７）で示されるものが挙げられる。
【００５８】
【化４】

【００５９】
式中、Ｒ^１及びＲ^２は同一または異なる芳香族モノカルボン酸残基、Ｘは炭素数２〜４のアルキレン基を表し、ｎは１〜１０の整数を表す。
【００６０】
Ｒ^１及びＲ^２としては、例えば、炭素数１〜１０のアルキル基及び／またはハロゲン（Ｃｌ、Ｂｒ等）で核置換（置換度１〜３）されていてもよい芳香族炭化水素基（フェニル基、トルイル基、キシレニル基、４−ブチルフェニル基、２，４−ジブチルフェニル基、２−メチル−４−クロロフェニル基、ノニルフェニル基等）が挙げられる。
また、Ｘとしては、例えば、炭素数２〜４の直鎖または分岐のアルキレン基（エチレン基、１，２−及び１，３−プロピレン基、１，２−、２，３−、１，３−、１，４−ブチレン基等）及びこれらのハロゲン置換された基（１−クロロメチルエチレン基、１−ブロモメチルエチレン基等）が挙げられる。
（Ｂ２）の具体例としては、ポリエチレングリコール（重合度３〜１０）ジ安息香酸エステル、ポリプロピレングリコール（重合度３〜１０）ジ安息香酸エステル等が挙げられる。
【００６１】
上記（Ｂ１）及び（Ｂ２）はそれぞれ単独で、あるいは併用で、あるいはこれら以外の上記の他の可塑剤の１種以上と併用して用いられる。併用する場合は、特に（Ｂ１）の場合は耐吸湿性の観点から、（Ｂ２）の場合は低温特性、特に低温でのエアバッグドアの開裂性の観点から、上記（Ｂ）中の（Ｂ１）又は（Ｂ２）の含有量が５０重量％以上、特に７０重量％以上であることが望ましい。
【００６２】
本発明のスラッシュ成形用材料において、上記（Ｂ）の配合割合は、上記（Ａ）１００重量部に対して８０重量部以下が好ましく、より好ましくは２〜７０重量部、更に好ましくは５〜５０重量部である。（Ｂ）は成形時の溶融粘度の観点から２重量部以上がより好ましく、経時的なブリードアウトの観点から８０重量部以下が好ましい。
【００６３】
添加剤（Ｃ）としては、例えば、顔料、安定剤及びその他の添加剤が挙げられる。
顔料としては特に限定されず、例えば、公知の有機顔料及び／または無機顔料を使用することができ、上記（Ａ）１００重量部に対して、０〜５重量部配合することが好ましい。
有機顔料としては、例えば、不溶性アゾ顔料、溶性アゾ顔料、銅フタロシアニン系顔料、キナクリドン系顔料等が挙げられ、無機系顔料としては、例えば、クロム酸塩、フェロシアン化合物、金属酸化物、硫化セレン化合物、金属塩類（硫酸塩、珪酸塩、炭酸塩、燐酸塩等）、金属粉末、カーボンブラック等が挙げられる。
【００６４】
安定剤としては特に限定されず、例えば、公知の酸化防止剤及び／または紫外線吸収剤を使用することができ、上記（Ａ）１００重量部に対して、０〜５重量部配合することが好ましい。
酸化防止剤としては、例えば、フェノール系［２，６−ジ−ｔ−ブチル−ｐ−クレゾール、ブチル化ヒドロキシアニソール等］；ビスフェノール系［２，２’−メチレンビス（４−メチル−６−ｔ−ブチルフェノール）等］；リン系［トリフェニルフォスファイト、ジフェニルイソデシルフォスファイト等］等が挙げられる。
紫外線吸収剤としては、例えば、ベンゾフェノン系［２，４−ジヒドロキシベンゾフェノン、２−ヒドロキシ−４−メトキシベンゾフェノン等］；ベンゾトリアゾール系［２−（２’−ヒドロキシ−５’−メチルフェニル）ベンゾトリアゾール等］、サリチル酸系［フェニルサリシレート等］；ヒンダードアミン系［ビス（２，２，６，６−テトラメチル−４−ピペリジル）セバケート等］等が挙げられる。
【００６５】
その他の添加剤としては、例えば、ブロッキング防止剤、離型剤及び難燃剤等が挙げられる。
【００６６】
ブロッキング防止剤としては特に限定されず、公知の無機系ブロッキング防止剤、有機系ブロッキング防止剤を使用することができる。無機系ブロッキング防止剤としては、例えば、シリカ、タルク、酸価チタン、炭酸カルシウム等が挙げられ、有機系ブロッキング防止剤としては、例えば、粒子径１０μｍ以下の熱硬化性樹脂（熱硬化性ポリウレタン樹脂、グアナミン系樹脂、エポキシ系樹脂等）及び粒子径１０μｍ以下の熱可塑性樹脂（熱可塑性ポリウレタン樹脂、ポリ（メタ）アクリレート樹脂等）、フタル酸マレイミド粉末等が挙げられる。
ブロッキング防止剤の配合量は上記（Ａ）１００重量部に対して、０〜２重量部が好ましい。
【００６７】
離型剤としては特に限定されず、公知の離型剤が使用でき、例えば、フッ素系離型剤（リン酸フルオロアルキルエステル等）、シリコン系離型剤（ジメチルポリシロキサン、アミノ変性ジメチルポリシロキサン、カルボキシル変性ジメチルポリシロキサン等）、脂肪酸エステル系離型剤（アルカン（炭素数１１〜２４）酸アルケニル（炭素数６〜２４）エステル等）、リン酸エステル系離型剤（リン酸トリブチルエステル）等が挙げられる。離型剤の配合量は上記（Ａ）１００重量部に対し、０〜２重量部である。
【００６８】
難燃剤としては特に限定されず、公知の難燃剤、例えば、リン酸エステル系のもの、ハロゲン化水素系のもの等を使用することができる。
リン酸エステル系難燃剤としては、例えば、トリクレジルホスフェート（ＴＣＰ）、トリス（β−クロロエチル）ホスフェート、トリス（ジクロロプロピル）ホスフェート、トリス（ジブロムプロピル）ホスフェート、ブロモホスフェート等が挙げられる。ハロゲン化炭化水素系難燃剤としては、例えば、塩素化パラフィン、四臭化エチレンが挙げられる。該ハロゲン化炭化水素系難燃剤は酸化アンチモン、ジンクボレート等との併用が好ましい。難燃剤の配合量は上記（Ａ）１００重量部あたり、０〜２０重量部が好ましい。
【００６９】
上記（Ｃ）の合計の配合量は上記（Ａ）１００重量部に対して、０〜３４重量部が好ましく、より好ましくは０．０５〜２０重量部である。
【００７０】
本発明のスラッシュ成形用材料の製造方法は特に限定されないが、上記（Ｂ）及び上記（Ｃ）を含有する場合は、例えば以下の方法が例示できる。
▲１▼上記（Ａ）の粉体、（Ｂ）及び（Ｃ）を一括して混合装置で混合する方法。
▲２▼あらかじめ（Ｂ）及び（Ｃ）を混合しておき、これを（Ａ）の粉体と混合する方法。
▲３▼（Ａ）の粉体を製造する任意の段階であらかじめ（Ｂ）及び（Ｃ）の一部または全部を含有させておく方法。
これらうち製造工程の簡略化の点から▲２▼の方法が好ましい。
【００７１】
本発明において、スラッシュ成形用材料の製造装置は特に限定されず、公知の粉体混合装置を使用することができる。
粉体混合装置としては、例えば、高速剪断混合装置〔へンシェルミキサー（登録商標）等〕、低速混合装置〔ナウタミキサー（登録商標）、プラネタリーミキサー等〕等が挙げられる。
【００７２】
本発明のスラッシュ成形用材料の体積平均粒径は、粉体流動性及びスラッシュ成形時に金型の細部まで粉が入り込むという観点から、１００μｍ以上特に１３０μｍ以上が好ましく、成形表皮のピンホール発生の観点から、５００μｍ以下特に２００μｍ以下が好ましい。
また、粒径７５μｍ以下の粒子の割合は、粉塵による作業環境、粉体流動性及びスラッシュ成形時に金型の細部まで粉が入り込むという観点から２０重量％以下特に１５重量％以下が好ましい。
本明細書中、体積平均粒子径は、レーザー式光散乱法で測定した篩い下５０％の粒子径の値である。測定機器としては、例えばマイクロトラックＨＲＡ粒度分析計９３２０−Ｘ１００（日機装株式会社製）を挙げることができる。
【００７３】
本発明の成形用材料をスラッシュ成形法で成形するには、例えば、パウダー状にした本発明の成形用材料が入ったボックスと２００〜２８０℃に加熱した金型を共に揺動回転させ、パウダーを型内で溶融流動させた後冷却固化させ、表皮を製造する方法で好適に実施することができる。
本発明の成形用材料で成形された表皮の厚さは、０．５〜１．５ｍｍが好ましい。該表皮は自動車内装材、例えばインストルメントパネル、ドアトリム等の表皮に好適に使用される。
【００７４】
【実施例】
以下、製造例、実施例により本発明をさらに詳細に説明するが、本発明はこれらに限定されるものではない。
【００７５】
以下の例において使用したポリオールＩはＭｎが１０００のＰＢＡ、ポリオールＩＩはＭｎが９００のＰＨＩＰ、ポリオールＩＩＩはＭｎが２０００のポリエチレンアジペート、安定剤Ｉはチバスペシャリティーケミカルズ（株）社製イルガノックス１０１０、酸化チタンは石原産業（株）製タイペークＲ−８２０、分散剤Ｉは三洋化成工業（株）製サンスパールＰＳ−８、ケチミンＩはＨＤＡのＭＥＫケチミン、ケチミンＩＩは水添ＭＤＡのＭＥＫケチミン、ケチミンＩＩＩはイソホロンジアミンのＭＥＫケチミン、分散機Ｉはヤマト科学（株）製ウルトラディスパーザー、可塑剤Ｉは大八化学（株）社製ＣＲ７４１［一般式（５）でＲがフェニル基、ｑが１、Ｒ’が−Ｐｈ−イソプロピリデン−Ｐｈ−であるリン酸エステル］、可塑剤ＩＩは三洋化成工業（株）社製　サンソフトＥＢ３００、ブロッキング防止剤Ｉはフタル酸マレイミド樹脂粉末（体積平均粒子径３μｍ、融点２８０℃）である。
【００７６】
製造例１〜８
表１に記載の処方（重量部。表中では部と表示）に従って、以下のようにして、Ｕｐ（Ｕｐ１〜Ｕｐ８）の溶液を製造した。
温度計、撹拌機及び窒素吹込み管を備えた反応容器に、ポリオール、低分子ジオール及び１−オクタノールを仕込み、窒素置換した後、撹拌しながら１１０℃に加熱して溶融させた。続いて、ジイソシアネートを投入し、８５℃で６時間反応させてＮＣＯ末端Ｕｐを形成した。次いで、Ｕｐを６０℃に冷却した後、ＴＨＦ、安定剤及び酸化チタンを加えて（Ｕｐ７では、ＤＢＡを６０℃に冷却後に加えた。）、均一に混合して、Ｕｐの溶液を得た。それらのＵｐ（溶液）のＮＣＯ含量（重量％。表中では％と表示）を併せて表１に示した。
【００７７】
【表１】

【００７８】
製造例９
ジアミンのＭＥＫケチミン化物の製造
ジアミンと過剰のＭＥＫ（ジアミンに対して４倍モル量）を８０℃で２４時間還流させながら生成水を系外に除去した。その後減圧にて未反応のＭＥＫを除去してＭＥＫケチミン化物であるケチミンＩ〜ＩＩＩを得た。
【００７９】
製造例１０〜１４及び比較製造例１〜３
反応容器に、表２に記載の配合（重量部。表中では部と表示）でＵｐ及びケチミンを投入し、そこに１．３重量部の分散剤Ｉを溶解した水溶液３４０重量部を添加し、分散機Ｉを用いて９０００ｒｐｍの回転数で１分間混合した。この混合物を温度計、撹拌機及び窒素吹込み管を備えた反応容器に移し、窒素置換した後、撹拌しながら５０℃で１０時間反応さた。反応終了後、濾別及び乾燥を行い、ポリウレタン樹脂（Ｆ１〜Ｆ８）の粉末を製造した。
得られた樹脂のＭｎ、ＳＴｉ（℃）、ΔＳＴ（℃）、ハードセグメント含量（計算値）（重量％）、ウレア基含量（重量％）、芳香環含量（重量％）及び体積平均粒径（μｍ）を表２に示した。
【００８０】
【表２】

【００８１】
実施例１〜３、５及び比較例１〜３
表３に記載の樹脂の粉末１００重量部と１５重量部の可塑剤Ｉをへンシェルミキサー内に投入し２００ｒｐｍで１分間混合した。
混合後、８０℃で２時間熟成した後４０℃まで冷却し、１重量部のブロッキング防止剤Ｉを添加して、表３に記載の体積平均粒径（μｍ）及び粒子径が７５μｍ以下の微粒子の含量（重量％）を有するスラッシュ成形用材料（Ｓ１〜Ｓ３、Ｓ５〜Ｓ８）を製造した。
【００８２】
実施例４
表３に記載の樹脂の粉末１００重量部と１５重量部の可塑剤ＩＩをへンシェルミキサー内に投入し２００ｒｐｍで１分間混合した。
混合後、８０℃で２時間熟成した後４０℃まで冷却し、１重量部のブロッキング防止剤Ｉを添加して、表３に記載の体積平均粒径（μｍ）及び粒子径が７５μｍ以下の微粒子の含量（重量％）を有するスラッシュ成形用材料（Ｓ４）を製造した。
得られた材料について、レベリング時間（秒）を下記方法により測定した。
スミモールドＦＡ［住鉱潤滑油（株）製］を吹きつけ２５０℃に加熱した金型に、スラッシュ成形用材料（Ｓ１〜Ｓ８）を、３０秒間接触させ熱溶融後、室温中で１分間放置した後、水冷して成形シートを作成した。
得られた成形シートについて、溶融性及び耐熱性を下記方法により試験した。それらの結果を表３に示した。
【００８３】
【表３】

【００８４】
＜物性測定＞
（１）ＳＴｉ及びＳＴｅの測定方法
熱可塑性ウレタン樹脂粉末を１９０℃で２分間プレス成形し膜厚８００〜１２００μｍのフィルムを作成した。このフィルムを試料として、ＳＴｉ及びＳＴｅは、熱機械分析装置「サーモフレックスＴＭＡ８１４０」及び「ＴＡＳ１００」（理学電機株式会社製）を使用し、熱機械分析針入方式（以下、ＴＭＡと記す）により求めた。ＴＭＡチャートにおいて、「ＪＩＳ　Ｋ７１２１−１９８７、Ｐ．５、図３、階段状変化」の方法に準じて、ＳＴｉは補外ガラス転移開始温度（Ｔｉｇ、℃）と同じ方法で、ＳＴｅは補外ガラス転移終了温度（Ｔｅｇ、℃）と同じ方法でそれぞれ求めた。（ＴＭＡ測定条件：昇温速度５℃／分、荷重５ｇ、針直径０．５ｍｍ。）また、得られた樹脂粉末（Ｆ１）及び（Ｆ７）のＴＭＡチャートを図１及び図２にしめす。図中のＴＭＡ曲線（実線）の接線（破線）の交点の温度がＳＴｉ及びＳＴｅに相当する。ΔＳＴ＝ＳＴｅ−ＳＴｉである。
【００８５】
＜性能評価＞
溶融性、レベリング時間及び耐熱性の評価は、下記方法により行った。
（１）溶融性
成形シートの金型面と、その裏面の溶融状態を目視で観察し、以下の５段階で評価した。
５級：金型面は完全溶融。裏面は均一に溶解し、平坦であり、光沢がある状態
４級：金型面は完全溶融。裏面は均一に溶解しているが、やや凹凸がある。
３級：金型面は完全溶融。裏面に一部パウダーの溶け残りが存在する状態。
２級：金型面の溶融不十分。裏面は溶け残りが多い。
１級：全く溶融せず。
【００８６】
（２）レベリング時間
１９０℃に加熱したホットプレートにスリ鋼板をのせ、その上に試料粉末１０〜１４ｍｇをミクロスパチュラにとり落とす。落とす面積は４ｍｍ×８ｍｍになるようにする。スリ鋼板に落とした試料粉末が完全に溶融して表面が光るようになるまでの時間（秒）を測定する。
【００８７】
（３）耐熱性
成形シートを、循環乾燥機中に、１３０℃で２４時間放置し、その状態を以下の３段階で目視評価した。
◎：変化なし、○：シボは流れていないが、グロスアップする、×：シボ流れ、グロスアップ有り。
【００８８】
【発明の効果】
本発明のポリウレタン樹脂系スラッシュ成形用材料は下記の効果を有する。
１．耐熱性に優れ、高温の耐熱試験においても試験後の表皮外観がグロスアップしたり、表皮のシボが流れたりすることがない。
２．熱溶融性に優れるので、色ムラが無く、外観の優れた成形体を得ることができる。
３．粉末の長期貯蔵安定性がよい。
４．耐摩耗性に優れる成形体を得ることができる。
上記効果を奏することから本発明のスラッシュ成形用材料から得られる成形体及び自動車内装用スラッシュ成形表皮は、インストルメントパネル、ドアトリムをはじめ自動車の各種内装材として極めて有用である。また、表皮付きソファー等のインテリア家具等他の成形品への応用も可能である。
【図面の簡単な説明】
【図１】ウレタン樹脂粉末（Ｆ１）のＴＭＡチャートを示す。
【図２】ウレタン樹脂粉末（Ｆ８）のＴＭＡチャートを示す。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a slush molding material, particularly a slush molding material useful for automobile interiors.
[0002]
[Prior art]
Conventionally, the difference between the softening start temperature and the softening end temperature by the thermomechanical analysis penetrating method, and the softening start temperature in a specific range in order to improve the adhesiveness with the interlining, the washing resistance, and the dry cleaning resistance. A hot melt adhesive comprising a thermoplastic polyurethane resin has been proposed, and it is described that the hot melt adhesive can also be used as a slush molding material. (For example, see Patent Document 1)
[0003]
However, as a material for slush molding, particularly a material that can be suitably applied to the interior of automobiles, it is desirable to satisfy conditions such as heat resistance, a molded article having excellent appearance, excellent wear resistance, and the like. When attention is paid to a system material, a slush molding material satisfying these characteristics has not yet been known.
[0004]
[Patent Document 1]
Japanese Patent No. 2984921
[0005]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION An object of the present invention is to provide a slush molding material having improved fusibility during slush molding and having excellent heat resistance.
[0006]
[Means for Solving the Problems]
Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention. That is, the present invention comprises a thermoplastic polyurethane resin (A), and the difference (hereinafter abbreviated as ΔST) between the softening start temperature and the softening end temperature (hereinafter abbreviated as STi and STe, respectively) according to the thermomechanical analysis penetration method of the (A). ) Is 0 to 30 ° C. and STi is 135 to 200 ° C .; a molded product obtained by thermoforming the molding material; a slash for an automobile interior obtained by thermoforming the molded material Molded skin: Automotive interior material made of the molded skin.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
The thermoplastic polyurethane resin (A) in the present invention has an STi (measurement condition: heating rate 5 ° C./min, load 5 g, needle diameter 0.5 mm) of 135 to 200 ° C., preferably 145 to 180 ° C., and more preferably. Is 150 to 170 ° C. If it is lower than 135 ° C., the heat resistance of the skin deteriorates, and if it exceeds 200 ° C., the heat fusibility at the molding temperature deteriorates.
ΔST by the thermomechanical analysis penetration method is 0 to 30 ° C., preferably 2 to 27 ° C., and more preferably 3 to 25 ° C. If the temperature exceeds 30 ° C., it is impossible to achieve both the melting property and the heat resistance. Such a resin having a small ΔST has a sharp melt property.
[0008]
The thermomechanical analysis penetration method is described in, for example, "Basic of thermal analysis for material science" by Yasutoshi Saito [published by Kyoritsu Shuppan in 1990], p. Published by Realize Co., Ltd.] on page 68 and the method described in JP-A-10-259369.
[0009]
The thermoplastic polyurethane resin (A) in the present invention is not particularly limited, and examples thereof include the following polyurethane resins. That is, a hard segment (A1) having a number average molecular weight of 200 to 2,000, which is composed of a diisocyanate (a1) having a symmetric structure and a low molecular diamine (a2) and / or a low molecular diol (a3) having a symmetric structure. ) And a soft segment (A2) composed of a polymer diol (a4) having a number average molecular weight of 500 to 5,000, wherein the content of the hard segment in the polyurethane resin is 5 to 50% by weight. Preferably, the polyurethane resin has an aromatic ring content of 35% by weight or less, and the aromatic ring content and the urea group content satisfy the following relational expression (i).
−0.1x + 2.5 ≦ y ≦ −0.1x + 6 (i)
In the formula, x represents the aromatic ring content (% by weight) in the polyurethane resin, and y represents the urea group content (% by weight) in the polyurethane resin.
[0010]
In the present specification, having a symmetric structure means that the planar chemical structural formula of the compound has a line symmetric structure. Hereinafter, the diisocyanate (a1) having the symmetric structure, the low-molecular diamine (a2) having a symmetric structure, and the low-molecular diol (a3) constituting the hard segment (A1) will be described.
[0011]
1. Diisocyanate (a1)
As the diisocyanate (a1), for example, an aliphatic diisocyanate having 2 to 18 carbon atoms (excluding carbon in the NCO group; the same applies hereinafter), for example, 1,2-ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6 Hexamethylene diisocyanate (hereinafter abbreviated as HDI), 1,8-octamethylene diisocyanate, 1,12-dodecamethylene diisocyanate, etc .; an alicyclic diisocyanate having 4 to 15 carbon atoms, for example, 4,4′-dicyclohexylmethane diisocyanate (Hereinafter abbreviated as hydrogenated MDI), cyclohexane-1,4-diisocyanate and the like; araliphatic diisocyanate having 8 to 15 carbon atoms, for example, p-xylylene diisocyanate, α, α, α ′, α′-tetramethyl Xylylene diisocyanate, etc .; 8 aromatic diisocyanates, such as 4,4'-diphenylmethane diisocyanate; and carbonate diisocyanates having 3 to 17 carbon atoms, such as bis (2-isocyanatoethyl) carbonate; and modified diisocyanates having a symmetric structure (Modified products of a symmetrical structure containing a urethane group, a carbodiimide group, a urea group, a uretdione group, and an oxazolidone group); and a mixture of two or more of these.
[0012]
Of these, preferred are 1,2-ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,12-dodecamethylene diisocyanate, bis (2-isocyanatoethyl) carbonate, 4'-dicyclohexylmethane diisocyanate, cyclohexane-1,4-diisocyanate, p-xylylene diisocyanate, α, α, α ', α'-tetramethylxylylene diisocyanate, and 4,4'-diphenylmethane diisocyanate. Particularly preferred are hydrogenated MDI and HDI, with HDI being even more preferred.
[0013]
A diisocyanate (a1 ′) having an asymmetric structure (for example, isophorone diisocyanate, trimethylhexamethylene diisocyanate, etc.) can be used in combination with the above (a1). The amount of (a1 ′) used is preferably such that (a1 ′) / (a1) is 0.25 or less in terms of molar ratio from the viewpoint of meltability.
[0014]
2. Diamine (a2)
Examples of the diamine (a2) include linear alkylene diamines having 2 to 18 carbon atoms, for example, 1,2-ethylene diamine, 1,4-tetramethylene diamine, 1,6-hexamethylene diamine (hereinafter abbreviated as HDA), 1 , 8-octamethylenediamine, 1,12-dodecamethylenediamine and the like; an alicyclic diamine having 4 to 15 carbon atoms, for example, 4,4'-dicyclohexylmethanediamine (hereinafter abbreviated as hydrogenated MDA), cyclohexane-1,4 An aromatic diamine having 8 to 15 carbon atoms, such as p-xylylenediamine, α, α, α ′, α′-tetramethylxylylenediamine; an aromatic diamine having 6 to 18 carbon atoms, such as 4,4′-diamino-diphenylmethane and the like; a carbonate diamine having 3 to 17 carbon atoms, for example, bis (2-aminoethyl) carbonate Preparative like; polyoxyethylene diamine (molecular weight of 500 or less) and the like; polyoxytetramethylene diamine (molecular weight of 500 or less); and mixtures of two or more thereof, and the like.
[0015]
Of these, linear alkylene diamine having 2 to 18 carbon atoms, bis (2-aminoethyl) carbonate, 4,4′-dicyclohexylmethanediamine, cyclohexane-1,4-diamine, p-xylylenediamine, α , Α, α ', α'-tetramethylxylylenediamine and 4,4'-diamino-diphenylmethane. More preferred are ethylenediamine, hydrogenated MDA and HDA, with HDA being particularly preferred.
[0016]
As a combination of the above (a1) and the above (a2), it is preferable that the residue of (a2) (excluding the amino group) has the same structure as the residue of (a1) (excluding the isocyanate group). . For example, HDI and HDA; bis (2-isocyanatoethyl) carbonate and bis (2-aminoethyl) carbonate; hydrogenated MDI and hydrogenated MDA; cyclohexane-1,4-diisocyanate and cyclohexane-1,4-diamine; -Xylylene diisocyanate and p-xylylene diamine; α, α, α ', α'-tetramethyl xylylene diisocyanate and α, α, α', α'-tetramethyl xylylene diamine; 4,4'-diphenylmethane diisocyanate And 4,4'-diamino-diphenylmethane.
[0017]
A diamine (a2 ′) having an asymmetric structure (for example, isophoronediamine, trimethylhexamethylenediamine, etc.) can be used in combination with the above (a2). The amount of (a2 ′) used is preferably such that the molar ratio of (a2 ′) / (a2) is 0.25 or less from the viewpoint of meltability.
[0018]
The above (a2) may be used in the form of ketimine. Examples of ketimines include ketimines obtained by reacting a diamine with a ketone having 3 to 6 carbon atoms [acetone, methyl ethyl ketone (hereinafter abbreviated as MEK), methyl isobutyl ketone, etc.].
[0019]
3. Low molecular diol (a3)
Examples of the low molecular diol (a3) include diols having a number average molecular weight of less than 500.
Specific examples of the low-molecular diol include, for example, aliphatic diols having 2 to 18 carbon atoms [linear diols (ethylene glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol (1,4- BG), 1,5-pentanediol, 1,6-hexanediol and the like, and a diol having a branched chain (propylene glycol, neopentyl glycol, 3-methyl-1,5-pentanediol (hereinafter abbreviated as MPD). ), 2,2-diethyl-1,3-propanediol, 1,2-, 1,3- or 2,3-butanediol, etc.); diols having a cyclic group having 3 to 18 carbon atoms [for example, And diols containing an aliphatic cyclic group having 3 to 30 carbon atoms (1,4-bis (hydroxymethyl) cyclohexene). , Hydrogenated bisphenol A, etc.); an aromatic cyclic group-containing diol having 6 to 15 carbon atoms ((m- and p-) xylylene glycol); pyrocatechol, resorcinol, hydroquinone, bisphenol A, bisphenol S, bisphenol F AO adduct of at least one member selected from the group consisting of diol and dihydroxynaphthalene (addition mole number 2 to 6); AO adduct of the above-mentioned diol (addition mole number 1 to 6)] and a mixture of two or more of these. No.
[0020]
Examples of the AO include ethylene oxide (EO), propylene oxide (PO), 1,2-, 1,3-, 1,4, and 2,3-butylene oxide, styrene oxide, 5 to 10 carbon atoms, or 5 to 10 carbon atoms. Examples of the above α-olefin oxide, epichlorohydrin, and a mixture of two or more of these (block or random addition).
[0021]
Among the above low molecular diols (a3), for example, diols (a3 ′) having a number average molecular weight of less than 500 and having a symmetric structure, for example, those represented by the following general formulas (1), (2) and (3) [ Hereinafter, these are referred to as (a3′1), (a3′2), and (a3′3). The above-mentioned (a3'1) ethylene oxide (hereinafter abbreviated as EO) or tetrahydrofuran (hereinafter abbreviated as THF) adduct (a3'4), glycol having a side chain (a3'5) and the like; A combination of at least two or more species is preferred. Of these, (a3′1), (a3′2), and (a3′3) are more preferred.
HO (CH ₂ ) M- (Q ¹ ) P- (CH ₂ ) MOH (1)
H (OCH ₂ CH ₂ ) NO-Q ² -O (CH ₂ CH ₂ O) nH (2)
H (OCH ₂ CH ₂ CH ₂ CH ₂ ) KO-Q ² -O (CH ₂ CH ₂ CH ₂ CH ₂ O) kH (3)
In equation (1), Q ¹ Represents a methylene group, 1,4-cyclohexylene group or 1,4-phenylene group, p is 0 or 1, m is 0 or an integer of 1 to 6 (provided that p is 0 or Q ¹ M is 1 to 6 when is a 1,4-phenylene group. ). In equations (2) and (3), Q ² Represents a bisphenol residue or a 1,4-phenylene group. n represents an integer of 1 to 3. In the formula (3), k is 1 or 2. However, Q ² K is 1 when is a residue of a bisphenol.
Examples of the bisphenols include groups represented by the following general formula (6).
[0022]
Embedded image

[0023]
In the formula, Z is a direct bond, an alkylene group having 1 to 6 carbon atoms, an alkylidene group having 2 to 6 carbon atoms, a cycloalkylidene group, an arylalkylidene group, O, SO, SO ₂ , CO, S, CF ₂ , C (CF ₃ ) ₂ Or NH.
[0024]
Examples of (a3′1) include linear alkylene diols having 2 to 18 carbon atoms, for example, ethylene glycol, 1,4-butanediol (hereinafter abbreviated as BG), and 1,6-hexanediol (hereinafter HG). Abbreviations), 1,8-octanediol, 1,12-dodecanediol; an alicyclic diol having 4 to 15 carbon atoms, for example, 1,4-bis (hydroxymethyl) cyclohexane, 1,4-cyclohexanediol; To 15 aromatic aliphatic diols such as p-xylylene glycol.
[0025]
Examples of (a3′2) include EO (2 to 6 mol) adduct of hydroquinone, EO (2 to 6 mol) adduct of bisphenol A, EO (2 to 6 mol) adduct of bisphenol F, and bisphenol And an EO (2 to 6 mol) adduct of S.
[0026]
Examples of (a3′3) include, for example, THF (2 to 4 mol) adduct of hydroquinone, THF (2 to 4 mol) adduct of bisphenol A, THF (2 to 4 mol) adduct of bisphenol F, and bisphenol And a THF (2 to 4 mol) adduct of S.
[0027]
Examples of the above (a3′4) include diethylene glycol, triethylene glycol and the like.
Examples of the above (a3′5) include neopentyl glycol and the like.
[0028]
Preferred as (a3 ′) are ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,4-bis (hydroxymethyl) cyclohexane and 1,4-cyclohexanediol, and particularly preferred. Is 1,4-butanediol, 1,6-hexanediol and 1,4-bis (hydroxymethyl) cyclohexane.
[0029]
Although (a2) and (a3) can be used alone, it is preferable to use (a2) and (a3) in combination, and the molar ratio is (a2) / (a3) = 0.5 to 10, particularly preferably 1 to 5.
[0030]
In the present invention, the number average molecular weight (hereinafter abbreviated as Mn) of the hard segment (A1) composed of (a1), (a2) and / or (a3) is preferably 200 to 2,000, more preferably 300 to 1,000. It is preferably at least 200 from the viewpoint of sharp meltability, and is preferably at most 2,000 from the viewpoint of STi. Mn of the hard segment (A1) can be obtained from the following formula (ii).
[Weight of (a1) + weight of (a2) + weight of (a3)] / [moles of (a1) −moles of (a2) −moles of (a3)] (ii)
[0031]
The content of the hard segment (A1) [total of (a1) + (a2) + (a3)] in the above (A) is preferably 5% by weight or more from the viewpoint of heat resistance of the skin, and from the viewpoint of STi. It is preferably at most 50% by weight. It is more preferably from 8 to 40% by weight, particularly preferably from 10 to 30% by weight.
[0032]
4. Polymer diol (a4)
Hereinafter, the polymer diol (a4) constituting the soft segment (A2) will be described. The polymer diol (a4) preferably has a Mn of 500 to 5,000, more preferably 700 to 3,000, and preferably has a weight average molecular weight (hereinafter abbreviated as Mw) / Mn ratio of 1.0 to 5,000. It has a ratio of 3.0, particularly preferably 1.0 to 2.0. Mn is preferably 500 or more from the viewpoint of texture and STi, and preferably 5000 or less from the viewpoint of sharp meltability. Mw and Mn of (a4) are measured by gel permeation chromatography (hereinafter abbreviated as GPC) using tetrahydrofuran as a solvent.
[0033]
Examples of the above (a4) include polyether diol, polyester diol, polysiloxane glycol, polybutadiene glycol, acrylic diol, polymer diol (a diol obtained by polymerizing a vinyl monomer in a high molecular weight diol) and these two types. Examples thereof include the above mixtures. Of these, polyether diol and polyester diol are preferred. This will be described below.
[0034]
Polyether diol
Examples of the polyether diol include compounds having a structure in which an alkylene oxide (hereinafter abbreviated as AO) is added to a compound having two active hydrogen atoms (a dihydric alcohol, a dihydric phenol, a primary monoamine, etc.), and a mixture thereof. And the like.
[0035]
Examples of the dihydric alcohol include alkylene glycols such as ethylene glycol, diethylene glycol, propylene glycol, 1,3- and 1,4-butanediol, 1,6-hexanediol, and neopentyl glycol, and diols having a cyclic group ( For example, those described in JP-B No. 45-1474) and the like. Examples of the dihydric phenol include monocyclic polyhydric phenols such as pyrogallol, hydroquinone, and phloroglucin; and bisphenols such as bisphenol A, bisphenol S, and bisphenol F.
Preferred as the compound having two active hydrogen atoms are dihydric alcohols, particularly 1,4-butanediol.
[0036]
Examples of AO include AO having 2 to 8 carbon atoms and substituted AO such as EO, propylene oxide (hereinafter abbreviated as PO), 1,2-, 1,3-, and 2,3-butylene oxide, THF, and styrene. Oxides and combinations of two or more of these (block or random addition) and the like. Of these, preferred are PO alone and a combination of EO and PO.
[0037]
Polyester diol
Examples of the polyester diol include (1) condensed polyester diol, (2) polylactone diol, (3) polycarbonate diol, and a combination of two or more of these.
The above (1) represents, for example, one or more diols (such as low molecular weight diols and / or polyether diols) and dicarboxylic acids or their ester-forming derivatives [lower alkyl (1 to 4 carbon atoms) esters, acid anhydrides, halides ( And the like, or the reaction of a diol with a dicarboxylic anhydride and AO.
The above (2) is obtained by ring-opening polymerization of a lactone using one or more of the above diols as an initiator.
The above (3) can be produced by reacting the above diol with an alkylene carbonate (ethylene carbonate).
[0038]
Among the raw material diols for the above (1), (2) and (3), examples of the low molecular diol include aliphatic low molecular diols (ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, , 6-hexanediol, etc.); low molecular weight diols having a cyclic group [for example, those described in JP-B-45-1474: 1,4-bis (hydroxymethyl) cyclohexane, m- or p-xylylene glycol, etc. A low molar addition product of an alkylene oxide of a bisphenol (with a molecular weight of less than 500); and a combination of two or more of these. Examples of the polyether diol include one of the polyether diols described above. These can be mentioned. Preferred are 1,4-butanediol and 1,6-hexanediol.
[0039]
Examples of the raw material dicarboxylic acid for the above (1) include aliphatic dicarboxylic acids having 2 to 10 carbon atoms (succinic acid, adipic acid, sebacic acid, glutaric acid, azelaic acid, maleic acid, fumaric acid, etc.), carbon dioxide Examples include aromatic dicarboxylic acids of Formulas 8 to 12 (terephthalic acid, isophthalic acid, and the like), and combinations of two or more of these.
[0040]
Preferred examples of (1) include polybutylene adipate diol and polyhexamethylene isophthalate diol (hereinafter abbreviated as PBA and PHIP, respectively), and combinations thereof.
[0041]
Examples of the raw material lactone for the above (2) include γ-butyrolactone, γ-valerolactone, ε-caprolactone, and a combination of two or more of these.
[0042]
The aromatic ring content x in the above (A) is preferably 35% by weight or less, and the urea group content (% by weight) y is preferably in a range satisfying the following relational expression (i). That is, it is preferable that y does not exceed −0.1x + 6 from the viewpoint of meltability, y is preferably at least −0.1x + 2.5 from the viewpoint of heat resistance, and x is 35% by weight from the viewpoint of low-temperature characteristics. The following is preferred.
−0.1x + 2.5 ≦ y ≦ −0.1x + 6 (i)
Further, it is preferable that the following formula (i ″) is satisfied and x is 1 to 30% by weight,
−0.1x + 2.5 ≦ y ≦ −0.1x + 5.5 (i ″)
In particular, it is preferable that the following formula (i ′ ″) is satisfied and x is 2 to 30% by weight,
−0.1x + 2.5 ≦ y ≦ −0.1x + 5.5 (i ′ ″)
From the viewpoint of wear resistance, it is most preferable that the following formula (i ′) is satisfied and x is 5 to 25% by weight.
−0.1x + 3 ≦ y ≦ −0.1x + 5 (i ′)
In this specification, the content of the aromatic ring means the content of the aromatic ring portion in (A). The urea group content is the content of the -NHCONH- group in (A).
[0043]
Mn of the thermoplastic polyurethane resin (A) in the present invention is preferably 4000 or more from the viewpoint of resin strength, and is preferably 40,000 or less from the viewpoint of STi. More preferably, it is 8,000 to 25,000.
Mn is measured by a GPC method using N, N-dimethylformamide (hereinafter abbreviated as DMF) as a solvent.
[0044]
The above (A) is a one-shot method in which the above (a1) and the active hydrogen-containing component [the above (a2) and / or the above (a3), and the above (a4) and, if necessary, the polymerization terminator (a5)] are reacted in one step. Reacting a diol [(a4) and optionally (a3)] and optionally (a5) with an excess of (a1) to form an NCO-terminated urethane prepolymer (hereinafter abbreviated as Up); The active hydrogen-containing component [(a2) and / or (a3) and, if necessary, (a5)] may be reacted to produce a prepolymer. Preferred is the prepolymer method.
[0045]
The above (A) is preferably obtained as a powder. The method for obtaining the powder of (A) is as follows: (1) The block or pellet (A) obtained by the above method is pulverized by a method such as a freeze pulverization method or a freeze pulverization method, and the powder of (A) is obtained. (2) Up obtained by reacting (a4) and optionally (a3) and / or (a5) with an excess of (a1) in the absence or presence of a solvent. Is dispersed in water containing a dispersion stabilizer using a high-speed stirrer to react water and / or (a2) with (a5) if necessary; (3) in the absence of a solvent or in the presence of a solvent. A method in which Up obtained in the same manner as in 2) is dispersed in a non-aqueous dispersion medium (hexane, heptane, etc.) containing a dispersion stabilizer, and (a2) is reacted with (a5) if necessary. In these methods (1) to (3), (a5) may be added at any time of the production of the prepolymer or the production of the urethane resin. Among these methods, a particularly preferred production method is the method (2).
[0046]
In the above methods (2) and (3), the dispersion comprising a dispersion stabilizer and water or a non-aqueous dispersion medium with respect to 100 parts by weight of the mixture (M) of Up, the above (a2) and, if necessary, the above (a5). The amount of the stabilizer liquid is preferably 50 parts by weight or more, more preferably 100 to 1000 parts by weight, from the viewpoint of the dispersion state of (M) and the particle size of the obtained resin powder. If necessary, the mixture (M) may be heated (for example, 40 to 100 ° C.) in order to reduce the viscosity, and may be used for isocyanates such as ester solvents, ketone solvents, chlorine solvents, and aromatic solvents. An inert organic solvent may be added. The rotation speed of the high-speed dispersing machine is preferably at least 1000 rpm, more preferably 3000 to 10000 rpm.
[0047]
In this case, the above (a2) and, if necessary, the above (a5) may be added after Up is dispersed in water, or may be added immediately before Up is dispersed, but the reaction is performed more uniformly. The latter is preferred in that respect.
[0048]
Examples of the above (a5) include monovalent alcohols having 1 to 12 carbon atoms (methanol, ethanol, n-butanol, n-octanol, 2-ethylhexanol, cellosolve, phenol alkylene oxide adducts and the like) and carbon atoms And monoamines of 1 to 12 [diethylamine, dibutylamine (hereinafter abbreviated as DBA), diethanolamine, etc.] and the like. Of these, monohydric alcohols are preferable, and n-octanol and 2-ethylhexanol are particularly preferable.
[0049]
In the urethanization reaction, a known catalyst can be used if necessary. Specific examples of the catalyst include, for example, organometallic compounds [tin-based catalysts such as dibutyltin dilaurate, dioctyltin dilaurate, stannas octate and the like; lead-based catalysts such as lead octenoate and the like]; amines [triethylamine, Triethylenediamine, diazabicycloundecene (manufactured by San Apro Co., Ltd., DBU)], and a combination of two or more of these. The amount of the catalyst used is not particularly limited, but is preferably 0.001 to 0.05 parts by weight per 100 parts by weight of the above (A).
In the urethanization reaction, a known solvent (THF, DMF, toluene, MEK, etc.) can be used if necessary.
[0050]
The molding material of the present invention may be the above (A) alone, or may further contain a plasticizer (B), and if necessary, may be added to (A) or (A) and (B). It may contain the agent (C).
Examples of the above (B) include a phosphoric acid ester; an aromatic monocarboxylic acid diester of a poly (polymerization degree 3 to 10) alkylene (C2 to C3) glycol; a phthalic acid ester [dibutyl phthalate, dioctyl phthalate, Dibutylbenzyl phthalate, diisodecyl phthalate, etc.]; aliphatic dicarboxylic acid esters [di-2-ethylhexyl adipate, 2-ethylhexyl sebacate, etc.]; trimellitate esters [tri-2-ethylhexyl trimellitate, trimellitate] Trioctyl acid and the like]; and fatty acid esters [butyl oleate and the like]; and mixtures of two or more thereof.
[0051]
Preferred as the above (B) is a phosphoric acid ester from the viewpoint of moisture absorption resistance, particularly a phosphoric acid ester (B1) represented by the following general formula (4), and low-temperature characteristics, particularly air at a low temperature. From the viewpoint of the cleavability of the bag door, it is an aromatic monocarboxylic acid diester (B2) of a poly (polymerization degree 3 to 10) alkylene (C2 to C3) glycol represented by the following general formula (7).
[0052]
Embedded image

[0053]
In the formula, R is each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms which may be substituted with halogen, and a plurality of Rs may be the same or different. R 'represents a divalent organic group having 2 to 15 carbon atoms which may be substituted with halogen, and q represents an integer of 1 to 6.
[0054]
As R, for example, an aliphatic hydrocarbon group having 1 to 10 carbon atoms (methyl group, ethyl group, isopropyl group, n-butyl group, t-butyl group, hexyl group, etc.), an alkyl group having 1 to 4 carbon atoms And an aromatic hydrocarbon group (phenyl group, xyenyl group, cresyl group, ethylbenzyl group, butylbenzyl group and the like) which may be substituted, and halogen-substituted groups thereof. Preferably, it is a phenyl group, an alkylphenyl group, or a halogen-substituted phenyl group.
[0055]
R ′ is, for example, a divalent aliphatic hydrocarbon group having 2 to 15 carbon atoms (such as an ethylene group, a propylene group, an n-butylene group, a t-butylene group, or a hexylene group); Or a divalent aromatic hydrocarbon group which may contain an oxygen atom [phenylene group, biphenylene group, -Ph-CH ₂ -Ph-, -Ph-C (CH ₃ ) ₂ -Ph-, -Ph-SO-Ph- (Ph represents a phenylene group), bisphenols (bisphenol A, bisphenol F, bisphenol S, etc., excluding the hydroxyl group) and halogen-substituted groups thereof And the like.
Preferred are divalent aromatic hydrocarbon groups having 6 to 15 carbon atoms and optionally containing a sulfur or oxygen atom.
[0056]
Among those exemplified as (B1) above, particularly preferred are plasticizers in which R in the general formula (4) is a phenyl group, an alkylphenyl group, or a halogen-substituted phenyl group, and R ′ is a general formula (5) below. (B2).
-Ph '-(A-Ph') p- (5)
In the formula, Ph ′ represents a 1,4-phenylene group, p represents 0 or 1, and A represents a direct bond, a methylene group, an isopropylidene group or SO.
[0057]
Examples of the above (B2) include those represented by the following general formula (7).
[0058]
Embedded image

[0059]
Where R ¹ And R ² Represents the same or different aromatic monocarboxylic acid residues, X represents an alkylene group having 2 to 4 carbon atoms, and n represents an integer of 1 to 10.
[0060]
R ¹ And R ² Examples thereof include an aromatic hydrocarbon group (phenyl group, toluyl group, and the like) which may be nuclear-substituted (substitution degree: 1 to 3) with an alkyl group having 1 to 10 carbon atoms and / or halogen (such as Cl and Br). Xyenyl group, 4-butylphenyl group, 2,4-dibutylphenyl group, 2-methyl-4-chlorophenyl group, nonylphenyl group, etc.).
X is, for example, a linear or branched alkylene group having 2 to 4 carbon atoms (ethylene group, 1,2- and 1,3-propylene group, 1,2-, 2,3-, 1,3 -, 1,4-butylene group, etc.) and their halogen-substituted groups (1-chloromethylethylene group, 1-bromomethylethylene group, etc.).
Specific examples of (B2) include polyethylene glycol (polymerization degree 3 to 10) dibenzoate, polypropylene glycol (polymerization degree 3 to 10) dibenzoate, and the like.
[0061]
The above (B1) and (B2) are used alone or in combination, or in combination with one or more other plasticizers other than the above. In the case of using (B1) in combination with (B1), (B1) from the viewpoint of moisture absorption resistance, (B2) from the viewpoint of low-temperature characteristics, particularly the airbag door tearability at low temperatures. ) Or (B2) is preferably at least 50% by weight, particularly preferably at least 70% by weight.
[0062]
In the slush molding material of the present invention, the mixing ratio of the above (B) is preferably 80 parts by weight or less, more preferably 2 to 70 parts by weight, and still more preferably 5 to 50 parts by weight based on 100 parts by weight of the above (A). Parts by weight. (B) is more preferably 2 parts by weight or more from the viewpoint of melt viscosity at the time of molding, and is preferably 80 parts by weight or less from the viewpoint of bleed out over time.
[0063]
Examples of the additive (C) include a pigment, a stabilizer, and other additives.
The pigment is not particularly limited, and for example, known organic pigments and / or inorganic pigments can be used, and it is preferable to add 0 to 5 parts by weight based on 100 parts by weight of (A).
Examples of the organic pigment include an insoluble azo pigment, a soluble azo pigment, a copper phthalocyanine-based pigment, and a quinacridone-based pigment.Examples of the inorganic pigment include a chromate, a ferrocyanide compound, a metal oxide, and selenium sulfide. Examples include compounds, metal salts (sulfates, silicates, carbonates, phosphates, etc.), metal powders, carbon black and the like.
[0064]
The stabilizer is not particularly limited, and for example, a known antioxidant and / or ultraviolet absorber can be used. It is preferable to mix 0 to 5 parts by weight with respect to 100 parts by weight of (A). .
Examples of the antioxidant include phenol-based [2,6-di-t-butyl-p-cresol, butylated hydroxyanisole and the like]; bisphenol-based [2,2′-methylenebis (4-methyl-6-t- Butylphenol) and the like; and phosphorus-based [triphenylphosphite, diphenylisodecylphosphite and the like].
Examples of the ultraviolet absorber include benzophenone [2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, etc.]; benzotriazole [2- (2′-hydroxy-5′-methylphenyl) benzotriazole, etc. ], Salicylic acid type [phenyl salicylate etc.]; hindered amine type [bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate etc.] and the like.
[0065]
Other additives include, for example, an antiblocking agent, a release agent, a flame retardant, and the like.
[0066]
The blocking inhibitor is not particularly limited, and known inorganic blocking inhibitors and organic blocking inhibitors can be used. Examples of the inorganic antiblocking agent include silica, talc, acid value titanium, calcium carbonate, and the like. Examples of the organic antiblocking agent include a thermosetting resin having a particle diameter of 10 μm or less (thermosetting polyurethane resin). , A guanamine resin, an epoxy resin, etc.), a thermoplastic resin having a particle diameter of 10 μm or less (a thermoplastic polyurethane resin, a poly (meth) acrylate resin, etc.), a maleimide phthalate powder and the like.
The amount of the antiblocking agent is preferably from 0 to 2 parts by weight based on 100 parts by weight of the component (A).
[0067]
The release agent is not particularly limited, and a known release agent can be used. Examples of the release agent include a fluorine-based release agent (such as a fluoroalkyl phosphate ester) and a silicon-based release agent (dimethylpolysiloxane, amino-modified dimethylpolysiloxane). , Carboxyl-modified dimethylpolysiloxane, etc.), fatty acid ester release agent (alkane (C11-24) alkenyl (C6-24) ester, etc.), phosphate ester release agent (tributyl phosphate) And the like. The compounding amount of the release agent is 0 to 2 parts by weight based on 100 parts by weight of the above (A).
[0068]
The flame retardant is not particularly limited, and a known flame retardant, for example, a phosphoric acid ester type, a hydrogen halide type, or the like can be used.
Examples of the phosphate ester flame retardant include tricresyl phosphate (TCP), tris (β-chloroethyl) phosphate, tris (dichloropropyl) phosphate, tris (dibromopropyl) phosphate, bromophosphate, and the like. Examples of the halogenated hydrocarbon flame retardant include chlorinated paraffin and ethylene tetrabromide. The halogenated hydrocarbon flame retardant is preferably used in combination with antimony oxide, zinc borate and the like. The blending amount of the flame retardant is preferably 0 to 20 parts by weight per 100 parts by weight of the above (A).
[0069]
The total compounding amount of (C) is preferably 0 to 34 parts by weight, more preferably 0.05 to 20 parts by weight, based on 100 parts by weight of (A).
[0070]
The method for producing the slush molding material of the present invention is not particularly limited, but when it contains the above (B) and (C), for example, the following methods can be exemplified.
{Circle around (1)} A method in which the powder of (A), (B) and (C) are mixed together by a mixing device.
{Circle around (2)} A method in which (B) and (C) are mixed in advance and then mixed with the powder of (A).
{Circle around (3)} A method in which (B) and (C) are partially or wholly contained in an arbitrary step of producing the powder of (A).
Among them, the method (2) is preferable from the viewpoint of simplifying the manufacturing process.
[0071]
In the present invention, the production apparatus for the slush molding material is not particularly limited, and a known powder mixing apparatus can be used.
Examples of the powder mixing device include a high-speed shear mixing device (Henschel mixer (registered trademark), etc.) and a low-speed mixing device (Nauta mixer (registered trademark), planetary mixer, etc.).
[0072]
The volume average particle diameter of the material for slush molding of the present invention is preferably 100 μm or more, particularly preferably 130 μm or more, from the viewpoint of powder fluidity and that the powder enters the details of the mold during slush molding, and from the viewpoint of pinhole generation in the molded skin. Therefore, the thickness is preferably 500 μm or less, particularly preferably 200 μm or less.
Further, the proportion of particles having a particle diameter of 75 μm or less is preferably 20% by weight or less, particularly preferably 15% by weight or less, from the viewpoints of working environment due to dust, powder fluidity, and that powder enters into the details of a mold during slush molding.
In the present specification, the volume average particle diameter is a value of a particle diameter of 50% under a sieve measured by a laser light scattering method. As a measuring instrument, for example, a Microtrac HRA particle size analyzer 9320-X100 (manufactured by Nikkiso Co., Ltd.) can be mentioned.
[0073]
In order to mold the molding material of the present invention by the slush molding method, for example, a box containing the powdered molding material of the present invention and a mold heated to 200 to 280 ° C. are oscillated and rotated together to form a powder. Is melted and fluidized in a mold, and then cooled and solidified to suitably carry out a method for producing a skin.
The thickness of the skin formed with the molding material of the present invention is preferably 0.5 to 1.5 mm. The skin is suitably used for the interior material of automobiles, for example, the skin of instrument panels and door trims.
[0074]
【Example】
Hereinafter, the present invention will be described in more detail with reference to Production Examples and Examples, but the present invention is not limited thereto.
[0075]
Polyol I used in the following examples was PBA with Mn of 1000, polyol II was PHIP with Mn of 900, polyol III was polyethylene adipate with Mn of 2000, and stabilizer I was Irganox 1010 manufactured by Ciba Specialty Chemicals Co., Ltd. , Titanium oxide is Taipaque R-820 manufactured by Ishihara Sangyo Co., Ltd., dispersant I is Sunspearl PS-8 manufactured by Sanyo Chemical Industries, Ltd., ketimine I is MEK ketimine of HDA, ketimine II is MEK ketimine of hydrogenated MDA, Ketimine III is MEK ketimine of isophoronediamine, Disperser I is Ultra Disperser manufactured by Yamato Kagaku Co., Ltd., Plasticizer I is CR741 manufactured by Daihachi Chemical Co., Ltd. [R is a phenyl group in general formula (5), q is 1, R 'is -Ph-isopropylidene-Ph-]], a plasticizer II Is Sansoft EB300 manufactured by Sanyo Chemical Industries, Ltd., and the antiblocking agent I is maleimide phthalate resin powder (volume average particle diameter 3 μm, melting point 280 ° C.).
[0076]
Production Examples 1 to 8
A solution of Up (Up1 to Up8) was produced in the following manner according to the formulation (parts by weight; indicated as parts in the table) described in Table 1.
A polyol, a low molecular weight diol, and 1-octanol were charged into a reaction vessel equipped with a thermometer, a stirrer, and a nitrogen blowing tube, and after purging with nitrogen, the mixture was heated to 110 ° C. with stirring to be melted. Subsequently, diisocyanate was charged and reacted at 85 ° C. for 6 hours to form an NCO-terminated Up. Next, after Up was cooled to 60 ° C., THF, a stabilizer and titanium oxide were added (in Up7, DBA was added after cooling to 60 ° C.), and uniformly mixed to obtain an Up solution. Table 1 also shows the NCO content (% by weight; indicated in the table as%) of the Up (solution).
[0077]
[Table 1]

[0078]
Production Example 9
Production of MEK ketimine compound of diamine
The generated water was removed from the system while refluxing the diamine and excess MEK (4 times the molar amount with respect to the diamine) at 80 ° C. for 24 hours. Thereafter, unreacted MEK was removed under reduced pressure to obtain ketimines I to III, which are MEK ketimine compounds.
[0079]
Production Examples 10 to 14 and Comparative Production Examples 1 to 3
In a reaction vessel, Up and ketimine were charged in the proportions shown in Table 2 (parts by weight; indicated as parts in the table), and 340 parts by weight of an aqueous solution in which 1.3 parts by weight of dispersant I was dissolved was added thereto. Using a disperser I at 9000 rpm for 1 minute. This mixture was transferred to a reaction vessel equipped with a thermometer, a stirrer, and a nitrogen blowing tube, and after substituting with nitrogen, reacted at 50 ° C. for 10 hours while stirring. After the completion of the reaction, the resultant was separated by filtration and dried to produce a polyurethane resin (F1 to F8) powder.
Mn, STi (° C.), ΔST (° C.), hard segment content (calculated value) (% by weight), urea group content (% by weight), aromatic ring content (% by weight) and volume average particle size (%) of the obtained resin μm) are shown in Table 2.
[0080]
[Table 2]

[0081]
Examples 1-3, 5 and Comparative Examples 1-3
100 parts by weight of the resin powder shown in Table 3 and 15 parts by weight of the plasticizer I were charged into a Henschel mixer and mixed at 200 rpm for 1 minute.
After mixing, the mixture was aged at 80 ° C. for 2 hours, cooled to 40 ° C., and 1 part by weight of an antiblocking agent I was added. The fine particles having a volume average particle diameter (μm) and a particle diameter of 75 μm or less shown in Table 3 were obtained. Slush molding materials (S1 to S3, S5 to S8) having a content (% by weight) of slush.
[0082]
Example 4
100 parts by weight of the resin powder shown in Table 3 and 15 parts by weight of the plasticizer II were charged into a Henschel mixer and mixed at 200 rpm for 1 minute.
After mixing, the mixture was aged at 80 ° C. for 2 hours, cooled to 40 ° C., and 1 part by weight of an antiblocking agent I was added. The fine particles having a volume average particle diameter (μm) and a particle diameter of 75 μm or less shown in Table 3 were obtained. The slush molding material (S4) having the content (% by weight) was prepared.
The leveling time (second) of the obtained material was measured by the following method.
A slush molding material (S1 to S8) was brought into contact with a mold heated to 250 ° C. by spraying a Sumimold FA (manufactured by Sumiko Lubricating Oil Co., Ltd.) for 30 seconds, and after heat melting, allowed to stand at room temperature for 1 minute. Thereafter, the sheet was cooled with water to form a molded sheet.
The obtained molded sheet was tested for meltability and heat resistance by the following methods. Table 3 shows the results.
[0083]
[Table 3]

[0084]
<Physical property measurement>
(1) STi and STe measurement method
The thermoplastic urethane resin powder was press-molded at 190 ° C. for 2 minutes to form a film having a thickness of 800 to 1200 μm. Using this film as a sample, STi and STe were determined by a thermomechanical analysis penetration method (hereinafter referred to as TMA) using a thermomechanical analyzer “Thermoflex TMA8140” and “TAS100” (manufactured by Rigaku Corporation). Was. In the TMA chart, according to the method of “JIS K7121-1987, P.5, FIG. 3, stepwise change”, STi is the same as the extrapolated glass transition onset temperature (Tig, ° C.), and STe is the extrapolated glass. The transition end temperature (Teg, ° C) was determined by the same method. (TMA measurement conditions: heating rate 5 ° C./min, load 5 g, needle diameter 0.5 mm.) FIGS. 1 and 2 show TMA charts of the obtained resin powders (F1) and (F7). The temperature at the intersection of the tangent (broken line) of the TMA curve (solid line) in the figure corresponds to STi and STe. ΔST = STe−STi.
[0085]
<Performance evaluation>
Evaluation of meltability, leveling time and heat resistance was performed by the following methods.
(1) Meltability
The molten state of the mold surface and the back surface of the molded sheet was visually observed and evaluated according to the following five grades.
Grade 5: The mold surface is completely melted. Back side is uniformly dissolved, flat and glossy
Grade 4: The mold surface is completely melted. The back surface is uniformly dissolved, but has some irregularities.
Class 3: The mold surface is completely melted. A state where some undissolved powder is present on the back side.
Grade 2: Insufficient melting of the mold surface. The back has much unmelted residue.
First grade: No melting at all.
[0086]
(2) Leveling time
A pick-up steel plate is placed on a hot plate heated to 190 ° C., and 10 to 14 mg of the sample powder is dropped on a microspatula. The area to be dropped should be 4 mm x 8 mm. The time (seconds) required for the sample powder dropped on the pick-up steel plate to completely melt and the surface to glow is measured.
[0087]
(3) Heat resistance
The molded sheet was left in a circulation dryer at 130 ° C. for 24 hours, and the state was visually evaluated in the following three stages.
◎: no change, ：: no grain flow, but gross up, ×: grain flow, gross up.
[0088]
【The invention's effect】
The polyurethane resin-based slush molding material of the present invention has the following effects.
1. It has excellent heat resistance, and does not gloss up the surface of the skin after the test even in a high-temperature heat test, and does not have a texture of the skin.
2. Since it is excellent in heat melting property, it is possible to obtain a molded article having excellent appearance without color unevenness.
3. Good long-term storage stability of the powder.
4. A molded article having excellent wear resistance can be obtained.
Because of the above effects, the molded product and the slush molded skin for automobile interiors obtained from the slush molding material of the present invention are extremely useful as various interior materials for automobiles including instrument panels and door trims. Further, application to other molded articles such as interior furniture such as sofas with skins is also possible.
[Brief description of the drawings]
FIG. 1 shows a TMA chart of a urethane resin powder (F1).
FIG. 2 shows a TMA chart of a urethane resin powder (F8).

Claims (16)

It is made of a thermoplastic polyurethane resin (A), and the difference between the softening start temperature and the softening end temperature according to the thermomechanical analysis method of (A) is 0 to 30 ° C, and the softening start temperature is 135 to 200 ° C. A slush molding material, characterized in that: (A) having a number average molecular weight of 200 to 2,000 composed of a diisocyanate (a1) having a symmetric structure and a low molecular diamine (a2) and / or a low molecular diol (a3) having a symmetric structure. A polyurethane resin having a hard segment (A1) and a soft segment (A2) composed of a polymer diol (a4) having a number average molecular weight of 500 to 5,000, wherein the content of the hard segment in (A) is 5 to 50 The molding material according to claim 1, wherein the content of the aromatic ring in (A) is 35% by weight or less, and the content of the aromatic ring and the content of the urea group satisfy the following relational expression (i).
−0.1x + 2.5 ≦ y ≦ −0.1x + 6 (i)
[In the formula, x represents an aromatic ring content (% by weight) in (A), and y represents a urea group content (% by weight) in (A). ] The molding material according to claim 2, wherein the aromatic ring content x in (A) is 5 to 25% by weight, and the aromatic ring content and the urea group content y satisfy the following relational expression (i ').
−0.1x + 3 ≦ y ≦ −0.1x + 5 (i ′) (A1) is a diisocyanate (a1) having a symmetric structure, a low-molecular diamine (a2) having a symmetric structure and / or a low-molecular diol (a3 ′) having a symmetric structure, and has a number average molecular weight of 200. The molding material according to claim 2 or 3, wherein the number of hard segments is up to 2,000. (A2) is a linear alkylenediamine having 2 to 18 carbon atoms, bis (2-aminoethyl) carbonate, 4,4′-dicyclohexylmethanediamine, cyclohexane-1,4-diamine, p-xylylenediamine, α The molding material according to any one of claims 2 to 4, wherein the molding material is at least one selected from the group consisting of, α, α ', α'-tetramethylxylylenediamine and 4,4'-diamino-diphenylmethane. (A1) is 1,2-ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,12-dodecamethylene diisocyanate, bis (2-isocyanatoethyl) carbonate, 4,4 Selected from the group consisting of '-dicyclohexylmethane diisocyanate, cyclohexane-1,4-diisocyanate, p-xylylene diisocyanate, α, α, α', α'-tetramethylxylylene diisocyanate, and 4,4'-diphenylmethane diisocyanate The molding material according to any one of claims 2 to 5, which is at least one kind. The molding material according to any one of claims 2 to 6, wherein the residue (a2) has the same structure as the residue (a1). The molding material according to any one of claims 4 to 7, wherein (a3 ') is a diol represented by any of the following general formulas (1), (2), and (3).
^{_{HO (CH 2) m- (Q}} 1) p- (CH 2) mOH (1)
^{_{H (OCH 2 CH 2) nO}} -Q 2 -O (CH 2 CH 2 O) nH (2)
_{H (OCH 2 CH 2 CH 2} CH 2) kO-Q 2 -O (CH 2 CH 2 CH 2 CH 2 O) kH (3)
[In the formula (1), Q ¹ represents a methylene group, a 1,4-cyclohexylene group or a 1,4-phenylene group, p is 0 or 1, and m is 0 or an integer of 1 to 6 (provided that m is 1 to 6 when p is 0 or Q ¹ is a 1,4-phenylene group.). In the formula (2) and (3), ^{Q 2} represents a residue or 1,4-phenylene group of bisphenols. n represents an integer of 1 to 3. In the formula (3), k is 1 or 2. However, if Q ² is a residue of bisphenols, k is 1. ] A powder comprising a thermoplastic polyurethane resin (A) and a plasticizer (B), having a volume average particle size of 100 to 500 µm, and having a particle size of 75 µm or less and a content of 20 wt% or less. 9. The molding material according to any one of 1 to 8. The molding material according to claim 9, wherein (B) is a phosphate ester represented by the following general formula (4).

[Wherein, R is a monovalent hydrocarbon group having 1 to 10 carbon atoms which may be substituted with halogen, and a plurality of Rs may be the same or different. R 'represents a divalent organic group having 2 to 15 carbon atoms which may be substituted with halogen, and q represents an integer of 1 to 6. ] The molding material according to claim 10, wherein R in the general formula (4) is a phenyl group, an alkylphenyl group, or a halogen-substituted phenyl group, and R 'is a group represented by the following general formula (5).
-Ph '-(A-Ph') p- (5)
[In the formula, Ph ′ represents a 1,4-phenylene group, p represents 0 or 1, A represents a direct bond, a methylene group, an isopropylidene group or SO. ] The molding material according to claim 9, wherein (B) is an aromatic monocarboxylic acid diester of a polyalkylene glycol. The molding material according to any one of claims 1 to 12, further comprising an additive (C). A slush molded product obtained by heat molding the slush molding material according to any one of claims 1 to 13. A slush molded skin for automobile interiors, which is obtained by heating and molding the slush molding material according to any one of claims 1 to 14. An automotive interior material comprising the slush-molded skin according to claim 15.

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