JP4351376B2 - Heat-sensitive adhesive material, its attaching method, and method for producing heat-sensitive adhesive - Google Patents

Description

【００２５】
請求項１３に係る感熱性粘着材料は、請求項１１において前記固体可塑剤が、下記構造式で表されるベンゾトリアゾール化合物（化合物▲２▼）であることを特徴とする。
【００２６】
【化５】

【００２７】
請求項１４に係る感熱性粘着材料は、請求項１１において前記固体可塑剤が、下記構造式で表されるスルホンアミド化合物（化合物▲３▼）であることを特徴とする。
【００２８】
【化６】

【００２９】
請求項１５に係る感熱性粘着材料は、請求項１〜１４のいずれかにおいて、前記感熱性粘着層と支持体の間に、中空粒子を主成分とするアンダー層が付与されていることを特徴とする。
【００３０】
請求項１６に係る感熱性粘着材料は、請求項１〜１５のいずれかにおいて、前記感熱性粘着層上に、ロイコ染料と顕色剤を主成分とする感熱記録層が設けられていることを特徴とする。
【００３１】
請求項１７に係る感熱性粘着材料は、請求項１〜１６のいずれかに記載の感熱性粘着材料を被着体に貼着する方法であって、感熱性粘着材料を感熱性粘着層側の面からサーマルヘッドで加熱することにより、前記感熱性粘着剤を活性化させて粘着力を発現させ、この粘着力の発現した感熱性粘着材料を被着体に貼り付けることを特徴とする。
【００３２】
請求項１８に係る感熱性粘着剤の製造方法は、熱可塑性樹脂と可塑剤が複合した微粒子を主成分とする感熱性粘着剤の製造方法であって、熱可塑性樹脂の有機溶媒溶液と可塑剤の有機溶媒溶液を混合および乳化分散して得た分散液から、前記有機溶媒を完全に気化させて前記熱可塑性樹脂と前記可塑剤とを複合した微粒子を形成し、次いで、粘着付与剤の有機溶媒分散液を混合してなり、前記熱可塑性樹脂は、２−エチルヘキシルアクリレートからなることを特徴とする。この製造方法では前記熱可塑性樹脂、可塑剤（固体可塑剤）として、上記請求項に記載のものを使用することができる。
【００３３】
本発明者は、感熱性粘着材料について種々の研究を重ねた結果、熱可塑性樹脂と可塑剤が複合した微粒子、あるいは熱可塑性樹脂と可塑剤および粘着付与剤が複合した微粒子を主成分とした感熱性粘着層を支持体上に付与してなることを特徴とする感熱性粘着材料を提供することで、上記第１の課題が解決できた。
【００３４】
従来の感熱性粘着材料は、たとえば樹脂粒子と固体可塑剤粒子が別々に感熱性粘着層内に存在しているために、熱を印加されたときに、まず固体可塑剤が液状化に溶解し、それが樹脂内に相溶していき樹脂が軟化および粘着を発現するという熱活性化プロセスであった。
【００３５】
この問題点は固体可塑剤が液状化するプロセスとそれが樹脂内に相溶するプロセスという２段階プロセスを経ており、粘着を活性化させるために大きなエネルギーを必要とし非常に活性化装置等に付加がかかる。また液状化した可塑剤が樹脂内に相溶するプロセス時に１００％の可塑剤が樹脂内に相溶せず粘着力を十分に発現させることができない。
【００３６】
ところが本発明によればあらかじめ熱可塑性樹脂と固体可塑剤が分子レベルで複合した粒子形状をとっているために、液状化した可塑剤が樹脂内へ相溶するプロセスが必要としなく、また１００％の可塑剤が樹脂と相溶できるのである。
【００３７】
さらに、前記熱可塑性樹脂が、アクリル酸エステル共重合体、スチレンアクリル共重合体、エチレン酢酸ビニル共重合体から選ばれる少なくとも１種以上を用いることで、従来の感熱性粘着材料よりも強度な粘着力を発現でき、たとえばポリオレフィンラップに対しても一般粘着ラベルと同レベルの粘着力を得ることを見出した。
【００３８】
さらに、熱可塑性樹脂と可塑剤が複合した微粒子または、熱可塑性樹脂と可塑剤および粘着付与剤が複合した微粒子の体積平均粒子径が０．５μｍ〜１０．０μｍである感熱性粘着材料、熱可塑性樹脂のガラス転移点が０℃〜−７０℃である感熱性粘着材料、平均分子量が１０万〜３０万である熱可塑性樹脂を用いた感熱性粘着材料は、いずれも一層の粘着力を発現することができる。これらの特徴を生かした熱可塑性樹脂としては、アクリル酸エステル共重合体である２−エチルヘキシルアクリレートが挙げられる。
【００３９】
一方、前記可塑剤として固体可塑剤を用いることで粘着力のみならず、耐ブロッキング性についても改善できることを見出した。通常状態では微粒子内の可塑剤は固体状のために熱可塑性樹脂は活性化状態になっておらず粘着力は発現しない。そのため耐ブロッキング性を向上させることができるのである。
【００４０】
さらに、融点が５０〜１２０℃である可塑剤、常温で固体状態を示し、加熱により液状化後、２０℃温度環境下に保存したときに、再び固体化しないことを特徴とする可塑剤を用いた感熱性粘着材料は一層、耐ブロッキング性改善と高粘着力とくに低温環境条件下での高粘着力を発揮することができる。低温環境での高粘着力を持つ感熱性粘着材料について様々な技術手段が施されてきたが、十分な粘着力発現には至らなかった。通常用いられる固体可塑剤がある温度で液状化しそれが低温化に保管されると再度固体化し粘着力を消失してしまうのが技術的な要因である。さまざまな固体可塑剤の中から上記に述べた常温環境で固体化しない固体可塑剤を用いることで低温環境下での高粘着力を実現できたのである。
【００４１】
また、前記固体可塑剤としてヒンダードフェノール化合物、ベンゾトリアゾール化合物、スルホンアミド化合物から選ばれた少なくとも１種を用いることで、さらなる耐ブロッキング性改善機能を有する感熱性粘着材料を提供することができる。これらの固体可塑剤は熱可塑性樹脂や粘着付与剤との相溶性も非常に高いため、耐ブロッキング性向上ばかりでなく、粘着力の向上にも有効である。このような固体可塑剤としては特に、上記した化合物▲１▼、化合物▲２▼、化合物▲３▼から選ばれる少なくとも１種以上を用いることが好ましい。また、これらの固体可塑剤では、熱可塑性樹脂との組み合わせにより、特に粘着力について相乗効果が得られる。
【００４２】
さらには粘着層と支持体の間に、中空粒子を主成分とするアンダー層を設けることで、サーマルヘッドから供給される熱エネルギーを高効率に利用することができ、少ないエネルギーで十分な粘着力を発現させることができる。
【００４３】
本発明の感熱性粘着材料では感熱性粘着層上に、ロイコ染料と顕色剤を主成分とする感熱記録層（感熱発色層）を設けることでも、様々な付加価値が得られる。例えば感熱記録層側、感熱粘着層側から熱を印加することで、粘着活性化と感熱発色を同時に行うことができる。
【００４４】
本発明に係わる感熱性粘着材料の活性化方法としては、熱風活性化方式、熱ロール活性化方式、サーマルヘッド活性化方式などさまざまな活性化方式が可能であるが、サーマルヘッドを用いた活性化方式が一般的である。この場合、１つのプリンターで両面を熱印加して使用することが可能である。
【００４５】
【発明の実施の形態】
以下に、本発明の感熱性粘着材料にかかる特徴について詳細に説明する。本発明における感熱性粘着層を構成する固体可塑剤を、以下の［表１］〜［表７］（化合物１〜化合物３７）に列挙するが、必ずしもこの限りではない。なお、これらの表において、化合物１〜７はヒンダードフェノール化合物、化合物８〜１５はベンゾトリアゾール化合物、化合物１６〜２９はスルホンアミド化合物、化合物３０〜３７はフタル酸化合物である。
【００４６】
【表１】

【００４７】
【表２】

【００４８】
【表３】

【００４９】
【表４】

【００５０】
【表５】

【００５１】
【表６】

【００５２】
【表７】

【００５３】
これら固体可塑剤の中では、［表１］の化合物１（上記化合物▲１▼）、［表３］の化合物１１（上記化合物▲２▼）および、［表５］の化合物１７（上記化合物▲３▼）が粘着力、ブロッキング性の面から特に好ましい。
【００５４】
さらに、本発明における感熱性粘着剤層を構成する液体可塑剤を以下に列挙するが必ずしもこの限りではない。本発明で使用される液体可塑剤としてはアジピン酸ジブチル、アジピン酸ジ−２−エチルヘキシル、アジピン酸ジ−ｎ−ヘキシル、セバシン酸ジブチル、セバシン酸−２−エチルヘキシル、フタル酸ブチルヘキシル、フタル酸ブチルベンジル、フタル酸ジメチル、フタル酸ジブチル、フタル酸ジ−２−エチルヘキシル、フタル酸ジエチル、フタル酸ジヘプチル、フタル酸ジオクチル等が挙げられる。これら液体可塑剤は、マイクロカプセルに内包させて用いられるのが一般的である。
【００５５】
本発明における感熱性粘着剤層を構成する熱可塑性樹脂を以下に列挙するが必ずしもこの限りではない。熱可塑性樹脂の種類としては、（メタ）アクリル酸エステル共重合体、スチレン−イソプレン共重合体、スチレン−アクリル酸エステル共重合体、スチレン−ブタジエン共重合体、アクリロニトリル−ブタジエン共重合体、エチレン−酢酸ビニル共重合体、酢酸ビニル−アクリル酸エステル共重合体、エチレン−塩化ビニル共重合体、エチレン−アクリル酸エステル共重合体、酢酸ビニル−エチレン−塩化ビニル共重合体、酢酸ビニル−エチレン−アクリル酸エステル共重合体、酢酸ビニル−エチレン−スチレン共重合体、ポリブタジエン、ポリウレタン等の樹脂が挙げられる。これら熱可塑性樹脂の中で特にアクリル酸エステル共重合体、スチレン−アクリル共重合体、アチレン酢酸ビニル共重合体が粘着品質に好ましく、前記に記載した化合物１、化合物１１、化合物１７との組み合わせによりさらに粘着性、ブロッキング性の効果が相乗する。
【００５６】
本発明において、様々なワックスを添加することもできる。ワックスとしては例えば動植物性ワックス、合成ワックスなどのワックス類や高級脂肪酸、高級脂肪酸アミド、高級脂肪酸アニリド、芳香族アミンのアセチル化物、パラフィンワックス、木ろう、カルナウバろう、シェラック、モンタンろう、酸化パラフィン、ポリエチレンワックス、酸化ポリエチレン等が、高級脂肪酸としては、例えばステアリン酸、ベヘン酸等が、高級脂肪酸アミドとしては、例えばステアリン酸アミド、オレイン酸アミド、Ｎ−メチルステアリン酸アミド、エルカ酸アミド、メチロールベヘン酸アミド、メチロールステアリン酸アミド、メチレンビスステアリン酸アミド、エチレンビスステアリン酸アミド等が、高級脂肪酸アニリドとしては、例えばステアリン酸アニリド、リノール酸アニリド等が、芳香族アミンのアセチル化物としては、例えばアセトトルイジド等が、各々例示されるが、高級脂肪族アミドの中のステアリン酸アミドのエマルジョン粒子を用いることで粘着性に影響を与えないでブロッキングを改善することができる。
【００５７】
本発明における、アンダー層に用いる中空粒子は、アクリル系ポリマーや塩化ビニリデン系ポリマーなどの高分子化合物のものが挙げられる。
【００５８】
本発明に係わる感熱性粘着剤層には、粘着力を向上するために、粘着付与剤を添加することができる。本発明に用いる粘着付与剤の具体例としては、テルペン樹脂、脂肪族系石油樹脂、芳香族系石油樹脂、クマロンインデン樹脂、スチレン系樹脂、フェノール樹脂、テルペンフェノール樹脂、ロジン誘導体樹脂等が用いられる。これら粘着付与剤は、熱可塑性樹脂１００部に対し２００部以下、好ましくは２０〜１５０部の範囲で混合して用いられる。粘着付与剤の添加部数が２００部を越えるとブロッキングを生じ易くなる。
【００５９】
本発明に係わる感熱性粘着剤層には、フィラー等も本発明の目的を妨げない範囲で添加可能であり、例えばアルミニウム、亜鉛、カルシウム、マグネシウム、バリウム、チタン等の炭酸塩、酸化物、水酸化物、硫酸塩等、および天然シリカ、ゼオライト、カオリン、焼成カオリン等の粘度類を含む無機系顔料、澱粉、スチレン樹脂、ポリオレフィン樹脂、メラミン樹脂、アクリル樹脂、パラフィン、天然ワックス、合成ワックス等が使用可能である。
【００６０】
本発明に係わる感熱性粘着剤層には、感熱性粘着剤層と支持体との接着または感熱性粘着剤層内の凝集力を高める目的で、水性高分子バインダー、例えばポリビニルアルコール、ポリ酢酸ビニル、酸化澱粉、エーテル化澱粉、カルボキシメチルセルロース、ヒドロキシエチルセルロース等のセルロース誘導体、カゼイン、ゼラチン、アルギン酸ソーダ等を添加することができる。上記水性高分子バインダーの混合比率は、感熱性粘着シートの本来の粘着力を損なわない範囲で添加され、具体的には感熱性粘着剤層全固形分に対し３０重量％以下、より好ましくは１０重量％以下の範囲で用いられる。
【００６１】
本発明に係わる感熱性粘着剤層には上記成分以外に必要に応じて硬膜剤、防腐剤、染料、紫外線吸収剤、酸化防止剤、ｐＨ調節剤、消泡剤等の各種添加剤を添加することができる。
【００６２】
本発明に係わる支持体に好ましく用いられる原紙は、木材パルプと填料を主成分として構成される。木材パルプとしては、ＬＢＫＰ、ＮＢＫＰ等の化学パルプ、ＧＰ、ＰＧＷ、ＲＭＰ、ＴＭＰ、ＣＴＭＰ、ＣＭＰ、ＣＧＰ等の機械パルプ、ＤＩＰ等の古紙パルプ等のパルプを含み、必要に応じて従来公知の顔料やバインダー及びサイズ剤や定着剤、歩留まり向上剤、カチオン化剤、紙力増強剤等の各種添加剤を１種以上用いて混合し、長網抄紙機、円網抄紙機、ツインワイヤ抄紙機等の各種装置で支持体の製造が可能であり、酸性、中性、アルカリ性で抄造できる。また、該原紙は、金属ロールと合成樹脂ロールからなるカレンダー装置をオンマシン処理しても良い。その際、オフマシン処理しても良く、処理後に、更にマシンカレンダー、スーパーカレンダー等でカレンダー処理を施して平坦性をコントロールしても良い。
【００６３】
原紙に含まれる填料としては、例えば、軽質炭酸カルシウム、重質炭酸カルシウム、カオリン、タルク、硫酸カルシウム、硫酸バリウム、二酸化チタン、酸化亜鉛、硫化亜鉛、サチンホワイト、珪酸アルミニウム、ケイソウ土、珪酸カルシウム、珪酸マグネシウム、合成シリカ、水酸化アルミニウム、アルミナ、リトポン、ゼオライト、炭酸マグネシウム、水酸化マグネシウムのような白色無機顔料、スチレン系プラスチックピグメント、アクリル系プラスチックピグメント、ポリエチレン、マイクロカプセル、尿素樹脂、メラミン樹脂のような有機顔料等が挙げられる。
【００６４】
原紙に含まれるサイズ剤としては、例えば、酸性抄紙用ロジンサイズ剤、中性抄紙用変性ロジンサイズ剤、ＡＫＤ、ＡＳＡ、カチオンポリマー型サイズ剤等を挙げることができる。
【００６５】
本発明に係わる支持体としてはさらに、グラシン紙、アート紙、コーテッド紙、キャスト紙などの一般紙を用いることができ、填料、サイズ剤、紙力増強剤、染料等、通常抄紙で用いられる原材料を必要に応じて使用することが可能である。ポリエチレン、ポリプロピレン、ポリエチレンテレフタレート、ポリアミド等のプラスチックシート、およびこれらの合成繊維からなる合成紙や不織布、または合成樹脂を紙に片面、または両面にラミネートしたラミネート紙、金属箔、または金属箔と紙、蒸着紙、ホログラム処理を施した不透明シート、合成樹脂フィルムとの貼り合わせ品、マイカ紙、ガラスペーパー等も使用可能である。
【００６６】
本発明に係わる感熱性粘着剤層は、通常紙塗工用に用いられているブレードコーター、グラビアコーター、グラビアオフセットコーター、バーコーター、ロールコーター、ナイフコーター、エアナイフコーター、コンマコーター、Ｕコンマコーター、ＡＫＫＵコーター、スムージングコーター、マイクログラビアコーター、リバースロールコーター、４本あるいは５本ロールコーター、ディップコーター、落下カーテンコーター、スライドコーター、ダイコーター等、若しくはフレキソ、凸版、グラビア、オフセット等の各種印刷機を用いて支持体に塗工、印刷される。
【００６７】
支持体に塗工若しくは印刷の際の乾燥条件は使用される固体可塑剤が融解しない温度範囲で乾燥されなければならない。乾燥の手段としては熱風乾燥の他に赤外線、マイクロ波、高周波による熱源を利用した乾燥方法が使用できる。
【００６８】
感熱性粘着剤層の塗布量は、乾燥塗工量で通常２〜５０ｇ／ｍ² 、好ましくは５〜３５ｇ／ｍ² の範囲で塗布される。感熱性粘着剤層の塗工量が２ｇ／ｍ² 未満であると、加熱による接着を行う際に十分な接着力が得られない。また、５０ｇ／ｍ² を越えると接着機能が飽和し経済上好ましくない。
【００６９】
本発明において感熱記録層があっても良い。本発明に用いる感熱記録層の感熱記録用ロイコ染料、顕色剤に関しては、一般に感熱記録用紙に用いられているものであれば特に制限されない。
【００７０】
塩基性ロイコ染料の具体例としては、例えばフルオラン系化合物、トリアリールメタン系化合物、スピロ系化合物、ジフェニルメタン系化合物、チアジン系化合物、ラクタム系化合物、フルオレン系化合物等が挙げられるが、好ましくはそれらの吸収スペクトルの特性が５５０〜１０００ｎｍ間に少なくとも１個以上の極大吸収波長を有するものがよい。
【００７１】
このうちフルオラン系化合物としては、例えば３−ジエチルアミノ−６−メチル−７−アニリノフルオラン、３−ジブチルアミノ−６−メチル−７−アニリノフルオラン、３−（Ｎ−メチル−Ｎ−シクロヘキシルアミノ）−６−メチル−７−アニリノフルオラン、３−（Ｎ−エチル−Ｎ−イソペンチルアミノ）−６−メチル−７−アニリノフルオラン、３−（Ｎ−イソブチル−Ｎ−エチルアミノ）−６−メチル−７−アニリノフルオラン、３−［Ｎ−エチル−Ｎ−（３−エトキシプロピル）アミノ］−６−メチル−７−アニリノフルオラン、３−（Ｎ−エチル−Ｎ−ヘキシルアミノ）−６−メチル−７−アニリノフルオラン、３−ジペンチルアミノ−６−メチル−７−アニリノフルオラン、３−（Ｎ−メチル−Ｎ−プロピルアミノ）−６−メチル−７−アニリノフルオラン、３−（Ｎ−エチル−Ｎ−テトラヒドロフリルアミノ）−６−メチル−７−アニリノフルオラン、３−ジエチルアミノ−６−メチル−７−（ｐ−クロロアニリノ）フルオラン、３−ジエチルアミノ−６−メチル−７−（ｐ−フルオロアニリノ）フルオラン、３−（ｐ−トルイジノエチルアミノ）−６−メチル−７−アニリノフルオラン、３−ジエチルアミノ−６−メチル−７−（ｐ−トルイジノ）フルオラン、３−ジエチルアミノ−７−（３，４−ジクロロアニリノ）フルオラン、３−ピロリジノ−６−メチル−７−アニリノフルオラン、３−ジエチルアミノ−６−クロロ−７−エトキシエチルアミノフルオラン、３−ジエチルアミノ−６−クロロ−７−アニリノフルオラン、３−ジエチルアミノ−７−フェニルフルオラン、３−（ｐ−トルイジノエチルアミノ）−６−メチル−７−フェネチルフルオラン等が挙げられる。
【００７２】
又、トリールメタン系化合物としては、例えば３，３−ビス（ｐ−ジメチルアミノフェニル）−６−ジメチルアミノフタリド（別名：クリスタルバイオレットラクトン又はＣＶＬ）、３，３−ビス（ｐ−ジメチルアミノフェニル）フタリド、３−（ｐ−ジメチルアミノフェニル）−３−（１，２−ジメチルアミノインドール−３−イル）フタリド、３−（ｐ−ジメチルアミノフェニル）−３−（２−メチルインドール−３−イル）フタリド、３−（ｐ−ジメチルアミノフェニル）−３−（２−フェニルインドール−３−イル）フタリド、３，３−ビス（１，２−ジメチルインドール−３−イル）−５−ジメチルアミノフタリド、３，３−ビス（１，２−ジメチルインドール−３−イル）−６−ジメチルアミノフタリド、３，３−ビス（９−エチルカルバゾール−３−イル）−５−ジメチルアミノフタリド、３，３−（２−フェニルインドール−３−イル）−５−ジメチルアミノフタリド、３−ｐ−ジメチルアミノフェニル−３−（１−メチルピロール−２−イル）−６−ジメチルアミノフタリド等が挙げられる。
【００７３】
更に、スピロ系化合物としては、例えば３−メチルスピロジナフトピラン、３−エチルスピロジナフトピラン、３，３’−ジクロロスピロジナフトピラン、３−ベンジルスピロジナフトピラン、３−プロピルスピロベンゾピラン、３−メチルナフト−（３−メトキシベンゾ）スピロピラン、１，３，３−トリメチル−６−ニトロ−８’−メトキシスピロ（インドリン−２，２’−ベンゾピラン）等が、ジフェニルメタン系化合物としては、例えばＮ−ハロフェニル−ロイコオーラミン、４，４−ビス−ジメチルアミノフェニルベンズヒドリルベンジルエーテル、Ｎ−２，４，５−トリクロロフェニルロイコオーラミン等が、チアジン系化合物としては、例えばベンゾイルロイコメチレンブルー、ｐ−ニトロベンゾイルロイコメチレンブルー等が、ラクタム系化合物としては、例えばローダミンＢアニリノラクタム、ローダミンＢ−ｐ−クロロアニリノラクタム等が、フルオレン系化合物としては、例えば３，６−ビス（ジメチルアミノ）フルオレンスピロ（９，３’）−６’−ジメチルアミノフタリド、３，６−ビス（ジメチルアミノ）フルオレンスピロ（９，３’）−６’−ピロリジノフタリド、３−ジメチルアミノ−６−ジエチルアミノフルオレンスピロ（９，３’）−６’−ピロリジノフタリド等が挙げられる。またカラー塩基性ロイコ染料として３−ジエチルアミノ−６−メチル−７−クロロフルオラン、３−シクロヘキシルアミノ−６−クロロフルオラン、３−ジエチルアミノ−ベンゾ［α］フルオラン、３−ジブチルアミノ−ベンゾ［α］フルオラン、３−ジエチルアミノ−７−クロロフルオラン、３−ジエチルアミノ−７−メチルフルオラン、３−Ｎ−エチル−Ｎ−イソアミルアミノ−ベンゾ［α］フルオラン、３−Ｎ−エチル−Ｎ−ｐ−メチルフェニルアミノ−７−メチルフルオラン、３−ジエチルアミノ−６，８−ジメチルフルオラン、３−ジブチルアミノ−６−メチル−７−ブロモフルオラン、３，６−ビス（ジエチルアミノフルオラン）−γ−（４’−ニトロ）アニリノラクタム、ビス（１−ｎ−ブチル−２−メチルインドール−３−イル）フタリド、ビス（１−エチル−２−メチルインドール−３−イル）フタリド、３−（４−ジエチルアミノフェニル）−３−（１−エチル−２−メチルインドリル−３−イル）フタリド、３−（４−ジエチルアミノ−２−エトキシフェニル）−３−（１−エチル−２−メチルインドリル−３−イル）−４−アザフタリド、３−（４−ジエチルアミノフェニル）−３−（１−メチル−２−メチルインドリル−３−イル）フタリド、３−（４−ジエチルアミノ−２−メチルフェニル）−３−（１−エチル−２−メチルインドリル−３−イル）フタリド、３、３―ビス（４−ジメチルアミノフェニル）−６−ジエチルアミノフタリド、３、７―ビス（４−ジメチルアミノ）−１０−ベンゾリルフェノチアジン、３、３―ビス（４−ジエチルアミノ−６−エトキシフェニル）−４−アザフタリド、３−ジエチルアミノ−７−ジアニリノフルオラン、３−Ｎ−エチル−Ｎ−４−メチルフェニルアミノ−７−Ｎ−メチルアニリノフルオラン、３−ジエチルアミノ−７−Ｎ−ジベンジルアミノフルオラン、３，６−ジメトキシフルオラン、３，６−ジブトキシフルオラン、３’−メトキシ−４’−ラノキシフェニル−２−シチリルキノリン、２’、４’−ジオクトクシフェニル−２−シチリルキノリン等が挙げられる。
【００７４】
顕色剤の具体例としては一般に感圧記録紙や感熱記録紙に用いられているものであればよく、特に制限されないが、ビス（３−アリル−４−ヒドロキシフェニル）スルホン、α−ナフトール、β−ナフトール、ｐ−オクチルフェノール、４−ｔ−オクチルフェノール、ｐ−ｔ−ブチルフェノール、ｐ−フェニルフェノール、１，１−ビス（ｐ−ヒドロキシフェニル）プロパン、２，２−ビス（ｐ−ヒドロキシフェニル）プロパン（別名：ビスフェノールＡ又はＢＰＡ）、２，２−ビス（ｐ−ヒドロキシフェニル）ブタン、１，１−ビス（ｐ−ヒドロキシフェニル）シクロヘキサン、４，４’−チオビスフェノール、４，４’−シクロヘキシリデンジフェノール、２，２’−（２，５−ジブロム−４−ヒドロキシフェニル）プロパン、４，４−イソプロピリデンビス（２−ｔ−ブチルフェノール）、２，２’−メチレンビス（４−クロロフェノール）、４，４’−ジヒドロキシジフェニルスルホン、、４−ヒドロキシ−４’−メトキシジフェニルスルホン、４−ヒドロキシ−４’−エトキシジフェニルスルホン、４−ヒドロキシ−４’−イソプロポキシジフェニルスルホン、４−ヒドロキシ−４’−ブトキシジフェニルスルホン、ビス−（４−ヒドロキシフェニル）酢酸メチル、ビス−（４−ヒドロキシフェニル）酢酸ブチル、ビス−（４−ヒドロキシフェニル）酢酸ベンジル、２，４−ジヒドロキシ−２’−メトキシベンズアニリド等のフェノール性化合物、ｐ−ヒドロキシ安息香酸ベンジル、ｐ−ヒドロキシ安息香酸エチル、４−ヒドロキシフタル酸ジベンジル、４−ヒドロキシフタル酸ジメチル、５−ヒドロキシイソフタル酸エチル、３，５−ジ−ｔ−ブチルサリチル酸、３，５−ジ−α−メチルベンジルサリチル酸等の芳香族カルボン酸誘導体、芳香族カルボン酸又はその金属塩等が挙げられる。
【００７５】
本発明における感熱記録層において使用されるバインダーとしては、澱粉類、ヒドロキシエチルセルロース、メチルセルロース、エチルセルロース、カルボキシメチルセルロースなどのセルロース誘導体、カゼイン、ゼラチンなどのプロテイン、酸化澱粉、エステル化合物澱粉などのサッカロースの如き水性天然高分子化合物、ポリビニルアルコール、変性ポリビニルアルコール、ポリビニルピロリドン、ポリアクリル酸、ポリアクリル酸ソーダ、アクリル酸アミド−アクリル酸エステル共重合体、アクリル酸アミド−アクリル酸エステル−メタクリル酸３元共重合体、スチレン−無水マレイン酸共重合体のアルカリ塩、ラテックス、ポリアクリルアミド、スチレン−無水マレイン酸共重合体などの如き水溶性合成高分子化合物やラテックス類、エチレン−無水マレイン酸共重合体のアルカリ塩などの水溶性接着樹脂、ポリ酢酸ビニル、ポリウレタン、ポリアクリル酸エステル、スチレン−ブタジエン共重合体、アクリロニトリル−ブタジエン共重合体、アクリル酸メチル−ブタジエン共重合体、アクリロニトリル−ブタジエン−アクリル酸共重合体、エチレン−酢酸ビニル共重合体などのラテックスなどが挙げられる。
【００７６】
また、感熱記録層の感度をさらに向上させるために、増感剤として、Ｎ−ヒドロキシメチルステアリン酸アミド、ステアリン酸アミド、パルミチン酸アミドなどのワックス類、２−ベンジルオキシナフタレンなどのナフトール誘導体、ｐ−ベンジルビフェニル、４−アリルオキシビフェニルなどのビフェニル誘導体、１，２−ビス（３−メチルフェノキシ）エタン、２，２’−ビス（４−メトキシフェノキシ）ジエチルエーテル、ビス（４−メトキシフェニル）エーテルなどのポリエーテル化合物、炭酸ジフェニル、シュウ酸ジベンジル、シュウ酸ジ（ｐ−クロルベンジル）エステルなどの炭酸またはシュウ酸ジエステル誘導体などを添加することができる。
【００７７】
感熱記録層に使用される顔料としては、ケイソウ土、タルク、カオリン、焼成カオリン、炭酸カルシウム、炭酸マグネシウム、酸化チタン、酸化亜鉛、酸化ケイ素、水酸化アルミニウム、尿素−ホルマリン樹脂などが挙げられる。
感熱記録層の下部、すなわち支持体の上に感熱発色性を向上させ、印字によるカスを防止するための中間層を設けること、あるいは感熱記録層の上に発色汚れや耐水性などを付与する目的で保護層を設けることは何ら差し支えない。
感熱記録層、中間層、保護層を設ける塗工方法として、ブレード塗工法、グラビア塗工法、グラビアオフセット塗工法、バー塗工法、ロール塗工法、ナイフ塗工法、エアナイフ塗工法、コンマ塗工法、Ｕコンマ塗工法、ＡＫＫＵ塗工法、スムージング塗工法、マイクログラビア塗工法、リバースロール塗工法、４本あるいは５本ロール塗工法、ディップ塗工法、落下カーテン塗工法、スライド塗工法、ダイ塗工法、等公知の塗工方法が利用可能である。
【００７８】
【実施例】
以下、実施例により本発明を詳しく説明するが、本発明の内容は、実施例に限られるものではない。以下に示す部および％のいずれも重量基準である。また、塗工量を示す値は断わりのない限り乾燥後の塗工量である。尚、以下に示す実施例の中で、実施例１〜７は本発明の範囲に属しない参考例に相当する例である。
【００７９】
＜実施例１＞
〔熱可塑性樹脂と可塑剤の複合微粒子分散液［Ａ液］の調製〕
天然ゴムを主成分とし、それに対して２５重量％の比率でメタメチルアクリレートをグラフト重合した熱可塑性樹脂（ガラス転移点１０℃、平均分子量４５万）をトルエン／酢酸エチルの有機溶剤（トルエン：酢酸エチル＝８：２）中に固形分５０％となるように完全溶解させた。ついで液体可塑剤アジピン酸ジオクチルを前記熱可塑性溶解液１００部に対して４０部の処方比率になるように添加して十分に相溶するまで攪拌混合した。別に８％に調製されたのポリビニルアルコール１００部に対して前記熱可塑性樹脂と液体可塑剤溶解液を５０部添加して、液温度を１５℃に管理した条件で、平均粒径が１５．０μｍになるようにホモミキサーを用いて乳化分散を行い、Ｏ／Ｗエマルジョン分散液を得た。このエマルジョン分散液を８０℃に昇温させて有機溶剤が完全に気化するまで保管した。有機溶剤が完全に気化したあと液温が室温になるまで静置させ、その後に全体の固形分が３０％になるよう水を添加し熱可塑性樹脂と可塑剤の複合微粒子分散液［Ａ液］を調製した。
【００８０】
〔感熱性粘着剤層塗液［Ｂ液］の調製〕
複合微粒子分散液［Ａ液］を１３２．５部に、粘着付与剤としてテルペンフェノール５０％分散液１５．０部とを混合して、感熱性粘着剤層塗液［Ｂ液］を調製した。
【００８１】
〔染料分散液［Ｃ液］の生成〕
３−ジブチルアミノ−６−メチル−７−アニリノフルオラン１．０部とポリビニルアルコール１０％水溶液を１．０部と水２．０部の処方比率になる混合物をサンドグラインダーを用いて平均粒径が０．７〜１．０μｍになるように粉砕、分散化して［Ｃ液］を生成した。
【００８２】
〔顕色剤液［Ｄ液］の生成〕
４−ヒドロキシ−４’−イソプロポキシジフェニルスルホン３．０部とシリカ１．０部とポリビニルアルコール１０％水溶液４．０部と水１０．０部の処方比率になる混合物をサンドグラインダーを用いて平均粒径が３μｍ以下になるように粉砕、分散化して［Ｄ液］を生成した。
【００８３】
〔感熱液［Ｅ液］の生成〕
上記染料分散液［Ｃ液］を４．０部と顕色剤液［Ｄ液］を１８．０部と水３．０部の処方比率になる混合液を十分に攪拌して感熱液［Ｅ液］を生成した。
【００８４】
〔シリカ分散液［Ｆ液］の生成〕
シリカを１．０部とポリビニルアルコール１０％水溶液を１．０部と水２．０部の処方比率になる混合物をサンドグラインダーを用いて平均粒径が３．０μｍ以下になるように粉砕、分散化して［Ｆ液］を生成した。
【００８５】
〔保護層液［Ｇ液］の生成〕
上記シリカ分散液［Ｆ液］を４．０部、ポリビニルアルコール１０％水溶液を１０．０部、ステアリン酸亜鉛３０％分散液（中京油脂製Ｚ−７３０）を１．０部、ポリアミドエピクロルヒドリンの１２．５％溶解液を３．２部および水５．８部の処方比率になる混合液を十分に攪拌して保護層液［Ｇ液］を生成した。
【００８６】
〔感熱性粘着材料の作製〕
支持体の片面に、ワイヤーバーを用いて感熱液［Ｅ液］を坪量５０ｇ／ｍ² の上質紙に染料重量が約０．５ｇ／ｍ² および保護層液［Ｇ液］が乾燥重量３．５ｇ／ｍ² となるように順次、塗布および乾燥して、キャレンダー処理を行い表面を王研式平滑度計で２０００ｓにした。さらにその裏面に感熱性粘着剤層塗液の調製で作製した感熱性粘着剤層塗液［Ｂ液］を乾燥重量が１２ｇ／ｍ² になるように塗工、乾燥して本発明の感熱性粘着材料を得た。
【００８７】
＜実施例２＞
実施例１に用いられた天然ゴムを主成分とし、それに対して２５重量％の比率でメタメチルアクリレートをグラフト重合した熱可塑性樹脂（ガラス転移点１０℃、平均分子量４５万）のかわりにアクリル酸エステル樹脂（ガラス転移点１０℃、平均分子量５０万）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【００８８】
＜実施例３＞
実施例１に用いられた天然ゴムを主成分とし、それに対して２５重量％の比率でメタメチルアクリレートをグラフト重合した熱可塑性樹脂（ガラス転移点１０℃、平均分子量４５万）のかわりにスチレンアクリル樹脂（ガラス転移点５℃、平均分子量５０万）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【００８９】
＜実施例４＞
実施例１に用いられた天然ゴムを主成分とし、それに対して２５重量％の比率でメタメチルアクリレートをグラフト重合した熱可塑性樹脂（ガラス転移点１０℃、平均分子量４５万）のかわりにエチレン酢酸ビニル樹脂（ガラス転移点２５℃、平均分子量５０万）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【００９０】
＜実施例５＞
実施例１に用いられた天然ゴムを主成分とし、それに対して２５重量％の比率でメタメチルアクリレートをグラフト重合した熱可塑性樹脂（ガラス転移点１０℃、平均分子量４５万）のかわりにアクリル酸エステル樹脂（ガラス転移点１０℃、平均分子量５０万）に変更し、さらに複合微粒子の平均粒径を１５．０μｍから３．０μｍになるように調製した以外は同様にして本発明の感熱性粘着材料を得た。
【００９１】
＜実施例６＞
実施例１に用いられた天然ゴムを主成分とし、それに対して２５重量％の比率でメタメチルアクリレートをグラフト重合した熱可塑性樹脂（ガラス転移点１０℃、平均分子量４５万）のかわりにアクリル酸エステル樹脂（ガラス転移点−６５℃、平均分子量５０万）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【００９２】
＜実施例７＞
実施例１に用いられた天然ゴムを主成分とし、それに対して２５重量％の比率でメタメチルアクリレートをグラフト重合した熱可塑性樹脂（ガラス転移点１０℃、平均分子量４５万）のかわりにアクリル酸エステル樹脂（ガラス転移点１０℃、平均分子量２５万）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【００９３】
＜実施例８＞
実施例１に用いられた天然ゴムを主成分とし、それに対して２５重量％の比率でメタメチルアクリレートをグラフト重合した熱可塑性樹脂（ガラス転移点１０℃、平均分子量４５万）のかわりにアクリル酸エステル樹脂である２−エチルヘキシルアクリレート（ガラス転移点−６０℃、平均分子量２５万）に変更し、さらに複合微粒子の平均粒径を１５．０μｍから３．０μｍになるように調製した以外は同様にして本発明の感熱性粘着材料を得た。
【００９４】
＜実施例９＞
〔熱可塑性樹脂と可塑剤の複合微粒子分散液［Ｈ］調製〕
熱可塑性樹脂２−エチルヘキシルアクリレート（ガラス転移点−６０℃、平均分子量２５万）をトルエン／酢酸エチルの有機溶剤（トルエン：酢酸エチル＝８：２）中に固形分５０％となるように完全溶解させた。ついで固体可塑剤化合物３０（融点７３．０℃）をトルエン／酢酸エチルの有機溶剤（トルエン：酢酸エチル＝８：２）中に固形分５０％となるように完全溶解させた。さらに前記熱可塑性溶解液７０部に相溶するまで攪拌混合した。別に８％に調製されたのポリビニルアルコール１００部に対して前記熱可塑性樹脂と液体可塑剤溶解液を５０部添加して、液温度を１５℃に管理した条件で、平均粒径が３．０μｍになるようにホモミキサーを用いて乳化分散を行い、Ｏ／Ｗエマルジョン分散液を得た。このエマルジョン分散液を８０℃に昇温させて有機溶剤が完全に気化するまで保管した。有機溶剤が完全に気化したあと液温が室温になるまで静置させ、その後に全体の固形分が２５．０％になるよう水を添加し熱可塑性樹脂と可塑剤の複合微粒子分散液［Ｈ液］を調製した。
【００９５】
〔感熱性粘着剤層塗液［Ｉ液］の調製〕
複合微粒子分散液［Ｈ液］を１２５．０部に、粘着付与剤としてテルペンフェノール５０％分散液１５．０部とを混合して、感熱性粘着剤層塗液［Ｉ液］を調製した。
【００９６】
〔感熱性粘着材料の作製〕
支持体の片面に、ワイヤーバーを用いて感熱液［Ｅ液］を坪量５０ｇ／ｍ² の上質紙に染料重量が約０．５ｇ／ｍ² および保護層液［Ｇ液］が乾燥重量３．５ｇ／ｍ² となるように順次、塗布および乾燥して、キャレンダー処理を行い表面を王研式平滑度計で２０００ｓにした。さらにその裏面に感熱性粘着剤層塗液の調製で作製した感熱性粘着剤層塗液［Ｉ液］を乾燥重量が１２ｇ／ｍ² になるように塗工、乾燥して本発明の感熱性粘着材料を得た。
【００９７】
＜実施例１０＞
実施例９に用いられた可塑剤である化合物３０（融点７３℃）を化合物６（融点１５８℃）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【００９８】
＜実施例１１＞
実施例９に用いられた可塑剤である化合物３０（融点７３℃）を化合物８（融点１２９℃）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【００９９】
＜実施例１２＞
実施例９に用いられた可塑剤である化合物３０（融点７３℃）を化合物１８（融点１３５℃）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【０１００】
＜実施例１３＞
実施例９に用いられた可塑剤である化合物３０（融点１５８℃）を化合物４（融点６５℃）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【０１０１】
＜実施例１４＞
実施例９に用いられた可塑剤である化合物３０（融点７３℃）を化合物２（融点１０５℃）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【０１０２】
＜実施例１５＞
実施例９に用いられた可塑剤である化合物３０（融点７３℃）を化合物１（融点７７℃）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【０１０３】
＜実施例１６＞
実施例９に用いられた可塑剤である化合物３０（融点７３℃）を化合物１１（融点１０４℃）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【０１０４】
＜実施例１７＞
実施例９に用いられた可塑剤である化合物３０（融点７３℃）を化合物１７（融点８７℃）に変更した以外は同様にして本発明の感熱性粘着材料を得た。
【０１０５】
＜実施例１８＞
〔アンダー液［Ｊ液］の調製〕
中空粒子エマルジョン（中空率５０％、固形分２５％）４．０部とスチレンブタジエンラテックス（固形分５０％）０．４部とポリビニルアルコール（固形分１０％水溶液）１．０部および水１．１部を十分に混合してアンダー液［Ｊ液］を調製した。
【０１０６】
〔感熱性粘着材料の作製〕
支持体の片面に、ワイヤーバーを用いて感熱液［Ｅ液］を坪量５０ｇ／ｍ² の上質紙に染料重量が約０．５ｇ／ｍ² および保護層液［Ｇ液］が乾燥重量３．５ｇ／ｍ² となるように順次、塗布および乾燥して、キャレンダー処理を行い表面を王研式平滑度計で２０００ｓにした。さらにその裏面にアンダー液［Ｊ液］を乾燥重量が３ｇ／ｍ² になるように塗工、乾燥して、ついで実施例１５に用いられている感熱性粘着剤層塗液を乾燥重量が１２ｇ／ｍ² になるように塗工、乾燥して本発明の感熱性粘着材料を得た。
【０１０７】
＜比較例１＞
〔熱可塑性樹脂エマルジョン分散液［Ｋ液］の調製〕
天然ゴムを主成分とし、それに対して２５重量％の比率でメタメチルアクリレートをグラフト重合した熱可塑性樹脂（ガラス転移点１０℃、平均分子量４５万）をトルエン／酢酸エチルの有機溶剤（トルエン：酢酸エチル＝８：２）中に固形分５０％となるように完全溶解させた。別に８％に調製されたのポリビニルアルコール１００部に対して前記熱可塑性樹脂溶解液を５０部添加して、液温度を１５℃に管理した条件で、平均粒径が１５．０μｍになるようにホモミキサーを用いて乳化分散を行い、Ｏ／Ｗエマルジョン分散液を得た。このエマルジョン分散液を８０℃に昇温させて有機溶剤が完全に気化するまで保管した。有機溶剤が完全に気化したあと液温が室温になるまで静置させ、その後に全体の固形分が２５％になるよう水を添加し熱可塑性樹脂と可塑剤の複合微粒子分散液［Ｋ液］を調製した。
【０１０８】
〔固体可塑剤分散液［Ｌ液］の生成〕
固体可塑剤化合物３０を１０部とポリビニルアルコール１０％水溶液を１０部と水７．５部の処方比率になる混合物をサンドグラインダーを用いて平均粒径が０．７〜１．０μｍになるように粉砕、分散化して［Ｌ液］を生成した。
【０１０９】
〔感熱性粘着剤層塗液［Ｍ液］の調製〕
熱可塑性樹脂エマルジョン分散液［Ｋ液］を１２５部と固体可塑剤分散液［Ｌ液］を１００部および粘着付与剤としてテルペンフェノール５０％分散液２０部の処方比率になるように混合して、感熱性粘着剤層塗液［Ｍ液］を調製した。
【０１１０】
〔感熱性粘着材料の作製〕
支持体の片面に、ワイヤーバーを用いて感熱液［Ｅ液］を坪量５０ｇ／ｍ² の上質紙に染料重量が約０．５ｇ／ｍ² および保護層液［Ｇ液］が乾燥重量３．５ｇ／ｍ² となるように順次、塗布および乾燥して、キャレンダー処理を行い表面を王研式平滑度計で２０００ｓにした。さらにその裏面に感熱性粘着剤層塗液の調製で作製した感熱性粘着剤層塗液［Ｍ液］を乾燥重量が１２ｇ／ｍ² になるように塗工、乾燥して本発明の感熱性粘着材料を得た。
【０１１１】
以上の実施例、比較例により得られた感熱性粘着材料に対し、粘着性および耐ブロッキング性を以下の試験方法により評価した。なお、粒子径の測定は、掘場製作所製の粒度分布計ＬＡ−７００を用いて行った。
【０１１２】
＜粘着性＞
本発明の感熱性粘着材料を４．０ｃｍ×９．０ｃｍの長方形にカットし、大倉電気製感熱印字装置ＴＨ−ＰＭＤを用いて、ヘッド条件０．５４ｍＪ／ｄｏｔ、印字スピード４ｍｓ／ｌｉｎｅ、プラテン圧６ｋｇｆ／ｌｉｎｅの条件にて感熱性粘着層を熱活性化させる。ついで被着体（ポリオレフィンラップ）に加圧２ｋｇのゴムローラーで長手方向に貼り付けて、１分後に剥離角度１８０℃、剥離速度３００ｍｍ／ｍｉｎの条件で剥離させる。その時の粘着力の抵抗値を数値で示した。なお単位はｇｆ／４０ｍｍである。この試験を低温環境（０℃、１５％）、常温環境（２０℃、６５％）、高温環境（４０℃、８０％）の各環境で実施した。
【０１１３】
＜耐ブロッキング性＞
同一サンプルの感熱記録層の保護層面と感熱性粘着層面とを接触させ、２ｋｇ／ｃｍ² の圧力で５０℃、Ｄｒｙ条件下で２４時間試験した後、室温で放置後サンプルを剥し、その時の耐ブロッキング性を下記［表８］のようなランクで評価した。粘着性および耐ブロッキング性の評価結果を下記［表９］に示す。
【０１１４】
【表８】

【０１１５】
【表９】

【０１１６】
【発明の効果】
本発明の感熱性粘着材料は、粘着力を維持しつつ（低下させないで）ポリオレフィンへの粘着力が高く、しかも耐ブロッキング性に優れたものである。また、本発明の貼着方法によれば、上記感熱性粘着材料をポリオレフィンラップに、高い粘着力で粘着させることができる。さらに、本発明に係わる感熱性粘着剤の製造方法貼着方法によれば、簡便な工程で所定の感熱性粘着剤を提供することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat-sensitive adhesive material, a method for attaching the heat-sensitive adhesive material, and a method for producing a heat-sensitive adhesive for forming a heat-sensitive adhesive layer of the heat-sensitive adhesive material. It is related to a heat-sensitive pressure-sensitive adhesive sheet in which the stickiness persists even after the stickiness is expressed.
[0002]
[Prior art]
In recent years, the use of pressure-sensitive adhesive sheets for labels such as labels for price display, labels for product display (barcode), labels for quality display, labels for weighing display, labels for advertising (stickers) has increased. ing. There are various recording methods such as an inkjet recording method, a thermal recording method, and a pressure sensitive recording method.
[0003]
Conventional adhesive sheet with a configuration in which a pressure-sensitive adhesive layer and release paper are laminated on the opposite side of the label's information recording surface can be easily attached by simply peeling off the release paper at the time of bonding. Widely used.
[0004]
However, the pressure-sensitive adhesive sheet having a general configuration is used by peeling the release paper, but the peeled release paper is hardly collected and reused and is almost always disposed of. Also, the so-called pressure-sensitive adhesive layer has a tack, it is very difficult to handle after peeling the release paper, and if you try to peel off the pressure-sensitive adhesive sheet to re-attach when it is inadvertently attached to the adherend, The adhesive sheet curls or wrinkles, and in the worst case, there is a problem that the sheet is torn. In recent years, heat-sensitive adhesive sheets that do not exhibit adhesiveness at room temperature and do not require release paper have attracted attention.
[0005]
The heat-sensitive adhesive is composed of a solid plasticizer and / or a liquid plasticizer and a thermoplastic resin as essential components, and these are mixed with a tackifier, etc., and these mixtures are placed on the opposite side of the printed surface on the support. A heat-sensitive adhesive material is obtained by coating. The adhesive layer surface of the heat-sensitive adhesive material does not show any adhesiveness at room temperature, but it develops adhesiveness when heated, and maintains adhesiveness for a while after removing the heat source. First, it is considered that the solid plasticizer is melted and the adhesiveness is developed by dissolving the thermoplastic resin and the tackifier. In addition, liquid plasticizers are generally encapsulated in microcapsules, and are considered to develop adhesiveness by heating and causing shell breakage and shell permeation, and by dissolving the thermoplastic resin and tackifier as described above. .
[0006]
The heat-sensitive adhesive material is advantageous in terms of resource saving and environmental problems because it does not use release paper like the above-mentioned general adhesive material. Furthermore, since it can adhere | attach if it heats a heat sensitive adhesive material after making it contact | abut to a to-be-adhered body, a sticking mistake can be prevented.
[0007]
Even heat-sensitive adhesive materials having such advantages have some problems with conventional ones. One of the problems is adhesive strength. In recent years, in the food POS industry and the like, food wraps are being switched from polyvinyl chloride wraps to polyolefin wraps in order to prevent environmental problems, particularly dioxin generation. Although a POS label is affixed on such a wrap, polyolefin wraps have a problem that they are easily peeled off because they are much weaker in adhesiveness and wettability than adhesive wraps. Measures have been taken against such wrapping for adhesive materials made of general adhesive and release paper. Although efforts have been made to increase the adhesion to such wraps with respect to conventional heat-sensitive adhesive materials, they have not yet been fully satisfactory.
[0008]
Another problem is blocking. Blocking is a phenomenon that develops adhesiveness even though the adhesive is not intended, and may be induced when exposed to a temperature atmosphere higher than room temperature for a long time. In either the roll state or the state where the sheet is cut and stacked, once blocking is induced, the heat-sensitive adhesive layer and the outer surface (the surface opposite to the heat-sensitive adhesive layer across the support) ) Will not only interfere with paper feeding but also adversely affect printing on the outer surface.
[0009]
Therefore, as means for preventing blocking, a method of blending a wax having lubricity in a heat-sensitive adhesive (Japanese Patent Publication No. 62-21835), a method of adding or mixing an inorganic substance (Japanese Patent Laid-Open No. 2-282050) And a method of preventing blocking by protecting the surface of the solid plasticizer with an inorganic compound or colloidal particles and suppressing softening of the solid plasticizer (Japanese Patent Laid-Open Nos. 6-57223, 6-100847, and 6-100848) and the like.
[0010]
However, when a wax is blended, the anti-blocking effect is insufficient, and conversely, the tackiness is lowered. The blocking resistance is insufficient only by adding a normal inorganic substance. If the surface of the solid plasticizer is protected with inorganic compounds or colloidal particles, it takes time to melt and diffuse the solid plasticizer, and the stickiness of the heat-sensitive adhesive is unlikely to appear, resulting in problems such as a decrease in adhesive performance. Inadequate. In addition, blocking is improved by using a high melting point plasticizer, but side effects such as a significant decrease in adhesive strength occur, and it is transported and stored under low temperature conditions where blocking does not actually occur. The current situation is.
[0011]
[Problems to be solved by the invention]
Therefore, the first problem to be solved by the present invention is to obtain a heat-sensitive adhesive material having improved adhesive strength and blocking resistance, that is, while maintaining (without reducing) the adhesive strength, An object is to provide an improved heat-sensitive adhesive material. Moreover, the 2nd subject of this invention is providing the method of sticking the said thermosensitive adhesive material to a to-be-adhered body. Furthermore, the 3rd subject of this invention is providing the manufacturing method of the thermosensitive adhesive which forms the thermosensitive adhesive layer of the said thermosensitive adhesive material.
[0012]
[Means for Solving the Problems]
  The heat-sensitive adhesive material according to claim 1 is:After dissolving the thermoplastic resin and plasticizer in the organic solvent, emulsifying and dispersing, and then completely evaporating the organic solvent.A heat-sensitive adhesive layer comprising a heat-sensitive adhesive mainly composed of fine particles of a thermoplastic resin and a plasticizer is provided on the support.The thermoplastic resin is made of 2-ethylhexyl acrylate.It is characterized by that.
[0013]
  The heat-sensitive adhesive material according to claim 2 is:After dissolving the thermoplastic resin and plasticizer in the organic solvent, emulsifying and dispersing, and then completely evaporating the organic solvent.Thermoplastic resin and plasticityAgentComposite fine particlesAnd tackifiersA heat-sensitive adhesive layer comprising a heat-sensitive adhesive mainly composed ofThe thermoplastic resin is made of 2-ethylhexyl acrylate.It is characterized by that.
[0014]
The heat-sensitive adhesive material according to claim 3 is the heat-sensitive adhesive material according to claim 1 or 2, wherein the volume average particle diameter of the fine particles is 0.5 μm to 10.0 μm.
[0015]
The heat-sensitive adhesive material according to claim 4 is the thermosensitive adhesive material according to any one of claims 1 to 3, wherein the thermoplastic resin is at least selected from an acrylic ester copolymer, a styrene acrylic copolymer, and an ethylene vinyl acetate copolymer. It is a kind of thermoplastic resin.
[0016]
The heat-sensitive adhesive material according to claim 5 is characterized in that in any one of claims 1 to 4, the glass transition point of the thermoplastic resin is 0 ° C to -70 ° C.
[0017]
The heat-sensitive adhesive material according to claim 6 is characterized in that, in any one of claims 1 to 5, the thermoplastic resin has an average molecular weight of 100,000 to 300,000.
[0018]
  The heat-sensitive adhesive material according to claim 7 is:Claim 2InThe tackifier comprises terpene phenolIt is characterized by that.
[0019]
The heat-sensitive adhesive material according to claim 8 is characterized in that in any one of claims 1 to 7, the plasticizer is a solid plasticizer.
[0020]
The heat-sensitive adhesive material according to claim 9 is characterized in that, in claim 8, the solid plasticizer has a melting point of 50C to 120C.
[0021]
The heat-sensitive adhesive material according to claim 10 is the heat-sensitive adhesive material according to claim 9, wherein the solid plasticizer exhibits a solid state at room temperature and does not solidify again when stored in a 20 ° C temperature environment after liquefaction by heating. Features.
[0022]
A heat-sensitive adhesive material according to an eleventh aspect is characterized in that, in the tenth aspect, the solid plasticizer contains at least one selected from a hindered phenol compound, a benzotriazole compound, and a sulfonamide compound.
[0023]
A heat-sensitive adhesive material according to claim 12 is characterized in that, in claim 11, the solid plasticizer is a hindered phenol compound (compound (1)) represented by the following structural formula.
[0024]
[Formula 4]

[0025]
The heat-sensitive adhesive material according to claim 13 is characterized in that, in claim 11, the solid plasticizer is a benzotriazole compound (compound (2)) represented by the following structural formula.
[0026]
[Chemical formula 5]

[0027]
The heat-sensitive adhesive material according to claim 14 is characterized in that, in claim 11, the solid plasticizer is a sulfonamide compound (compound (3)) represented by the following structural formula.
[0028]
[Chemical 6]

[0029]
The heat-sensitive adhesive material according to claim 15 is characterized in that, in any one of claims 1 to 14, an under layer mainly composed of hollow particles is provided between the heat-sensitive adhesive layer and the support. And
[0030]
The heat-sensitive adhesive material according to claim 16 is any one of claims 1 to 15, wherein a heat-sensitive recording layer mainly comprising a leuco dye and a developer is provided on the heat-sensitive adhesive layer. Features.
[0031]
The heat-sensitive adhesive material according to claim 17 is a method of sticking the heat-sensitive adhesive material according to any one of claims 1 to 16 to an adherend, wherein the heat-sensitive adhesive material is disposed on the heat-sensitive adhesive layer side. Heating from the surface with a thermal head activates the heat-sensitive adhesive to develop an adhesive force, and the heat-sensitive adhesive material exhibiting the adhesive force is attached to an adherend.
[0032]
  The method for producing a heat-sensitive adhesive according to claim 18 is a method for producing a heat-sensitive adhesive mainly comprising fine particles in which a thermoplastic resin and a plasticizer are combined, and an organic solvent solution of the thermoplastic resin and a plasticizer Dispersion obtained by mixing and emulsifying dispersion of organic solvent solutionThen, the organic solvent is completely vaporized to form fine particles in which the thermoplastic resin and the plasticizer are combined,Dispersion of tackifier in organic solventLiquidmixtureThe thermoplastic resin is made of 2-ethylhexyl acrylate.It is characterized by that. In this production method, those described in the above claims can be used as the thermoplastic resin and plasticizer (solid plasticizer).
[0033]
The inventor has conducted various studies on the heat-sensitive adhesive material, and as a result, the heat-sensitive material mainly comprises fine particles of a thermoplastic resin and a plasticizer, or a fine particle of a thermoplastic resin, a plasticizer, and a tackifier. The first problem can be solved by providing a heat-sensitive adhesive material characterized in that a heat-sensitive adhesive layer is provided on a support.
[0034]
In conventional heat-sensitive adhesive materials, for example, resin particles and solid plasticizer particles are separately present in the heat-sensitive adhesive layer, so when heat is applied, the solid plasticizer first dissolves into a liquefied state. It was a heat activation process in which the resin became compatible in the resin and the resin developed softening and adhesion.
[0035]
This problem is a two-stage process: a process in which the solid plasticizer is liquefied and a process in which it is dissolved in the resin, which requires a large amount of energy to activate the adhesion and is extremely added to the activation device. It takes. Moreover, 100% of the plasticizer is not compatible with the resin during the process in which the liquefied plasticizer is compatible with the resin, and the adhesive force cannot be sufficiently developed.
[0036]
However, according to the present invention, a particle shape in which a thermoplastic resin and a solid plasticizer are combined at a molecular level is taken in advance, so that a process in which the liquefied plasticizer is compatible with the resin is not required, and 100% This plasticizer is compatible with the resin.
[0037]
Furthermore, when the thermoplastic resin uses at least one selected from an acrylic ester copolymer, a styrene acrylic copolymer, and an ethylene vinyl acetate copolymer, the adhesive is stronger than a conventional heat-sensitive adhesive material. It was found that the adhesive strength can be expressed, and for example, the same level of adhesive strength as that of a general adhesive label can be obtained for polyolefin wrap.
[0038]
Further, the heat-sensitive adhesive material, the thermoplastic resin having a volume average particle diameter of 0.5 μm to 10.0 μm of the fine particles in which the thermoplastic resin and the plasticizer are combined, or the fine particles in which the thermoplastic resin is combined with the plasticizer and the tackifier A heat-sensitive adhesive material having a glass transition point of the resin of 0 ° C. to −70 ° C. and a heat-sensitive adhesive material using a thermoplastic resin having an average molecular weight of 100,000 to 300,000 both exhibit a further adhesive force. be able to. Examples of the thermoplastic resin taking advantage of these characteristics include 2-ethylhexyl acrylate which is an acrylate copolymer.
[0039]
On the other hand, it has been found that not only adhesive strength but also blocking resistance can be improved by using a solid plasticizer as the plasticizer. Under normal conditions, the plasticizer in the fine particles is solid, so that the thermoplastic resin is not activated and does not exhibit adhesive strength. Therefore, blocking resistance can be improved.
[0040]
Furthermore, a plasticizer having a melting point of 50 to 120 ° C., a plasticizer that exhibits a solid state at ordinary temperature, does not solidify again when stored in a 20 ° C. temperature environment after liquefaction by heating, is used. The heat-sensitive adhesive material that has been used can further improve blocking resistance and exhibit high adhesive strength, particularly high adhesive strength under low-temperature environmental conditions. Various technical means have been applied to heat-sensitive adhesive materials having high adhesive strength in a low-temperature environment, but sufficient adhesive strength has not been achieved. A technical factor is that a solid plasticizer that is usually used is liquefied at a certain temperature and then solidified again when it is stored at a low temperature to lose its adhesive strength. By using the above-mentioned solid plasticizer that does not solidify in a normal temperature environment, high adhesive strength in a low temperature environment can be realized.
[0041]
Further, by using at least one selected from a hindered phenol compound, a benzotriazole compound, and a sulfonamide compound as the solid plasticizer, a heat-sensitive adhesive material having a further anti-blocking function can be provided. Since these solid plasticizers are very compatible with thermoplastic resins and tackifiers, they are effective not only in improving blocking resistance but also in improving adhesive strength. As such a solid plasticizer, it is particularly preferable to use at least one selected from the above-mentioned compound (1), compound (2), and compound (3). Moreover, in these solid plasticizers, a synergistic effect is obtained particularly with respect to adhesive strength by combination with a thermoplastic resin.
[0042]
Furthermore, by providing an under layer mainly composed of hollow particles between the adhesive layer and the support, the thermal energy supplied from the thermal head can be used with high efficiency, and sufficient adhesive force can be obtained with less energy. Can be expressed.
[0043]
In the heat-sensitive adhesive material of the present invention, various added values can be obtained by providing a heat-sensitive recording layer (heat-sensitive color developing layer) mainly composed of a leuco dye and a developer on the heat-sensitive adhesive layer. For example, by applying heat from the heat-sensitive recording layer side and the heat-sensitive adhesive layer side, adhesion activation and heat-sensitive color development can be performed simultaneously.
[0044]
As the activation method of the heat-sensitive adhesive material according to the present invention, various activation methods such as a hot air activation method, a thermal roll activation method, and a thermal head activation method are possible, but activation using a thermal head is possible. The method is common. In this case, it is possible to use by applying heat to both sides with one printer.
[0045]
DETAILED DESCRIPTION OF THE INVENTION
Below, the characteristic concerning the heat-sensitive adhesive material of this invention is demonstrated in detail. Although the solid plasticizer which comprises the thermosensitive adhesive layer in this invention is enumerated in the following [Table 1]-[Table 7] (compound 1-compound 37), it is not necessarily this limitation. In these tables, compounds 1 to 7 are hindered phenol compounds, compounds 8 to 15 are benzotriazole compounds, compounds 16 to 29 are sulfonamide compounds, and compounds 30 to 37 are phthalic acid compounds.
[0046]
[Table 1]

[0047]
[Table 2]

[0048]
[Table 3]

[0049]
[Table 4]

[0050]
[Table 5]

[0051]
[Table 6]

[0052]
[Table 7]

[0053]
Among these solid plasticizers, compound 1 in Table 1 (compound 1), compound 11 in Table 3 (compound 2), and compound 17 in Table 5 (compound ▲) 3 ▼) is particularly preferable from the viewpoints of adhesive strength and blocking properties.
[0054]
Furthermore, although the liquid plasticizer which comprises the heat-sensitive adhesive layer in this invention is enumerated below, it is not necessarily this limitation. Liquid plasticizers used in the present invention include dibutyl adipate, di-2-ethylhexyl adipate, di-n-hexyl adipate, dibutyl sebacate, 2-ethylhexyl sebacate, butylhexyl phthalate, butyl phthalate Examples include benzyl, dimethyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, diethyl phthalate, diheptyl phthalate, and dioctyl phthalate. These liquid plasticizers are generally used by being encapsulated in microcapsules.
[0055]
Although the thermoplastic resin which comprises the heat-sensitive adhesive layer in this invention is enumerated below, it is not necessarily this limitation. The types of thermoplastic resins are (meth) acrylic acid ester copolymer, styrene-isoprene copolymer, styrene-acrylic acid ester copolymer, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, ethylene- Vinyl acetate copolymer, vinyl acetate-acrylic acid ester copolymer, ethylene-vinyl chloride copolymer, ethylene-acrylic acid ester copolymer, vinyl acetate-ethylene-vinyl chloride copolymer, vinyl acetate-ethylene-acrylic Examples thereof include resins such as acid ester copolymers, vinyl acetate-ethylene-styrene copolymers, polybutadiene, and polyurethane. Among these thermoplastic resins, acrylic acid ester copolymers, styrene-acrylic copolymers, and acetylene vinyl acetate copolymers are particularly preferable for the adhesive quality, and in combination with Compound 1, Compound 11, and Compound 17 described above. Furthermore, the effects of tackiness and blocking properties are synergistic.
[0056]
In the present invention, various waxes can also be added. Examples of waxes include waxes such as animal and plant waxes, synthetic waxes, higher fatty acids, higher fatty acid amides, higher fatty acid anilides, acetylated aromatic amines, paraffin wax, wood wax, carnauba wax, shellac, montan wax, oxidized paraffin, Polyethylene wax, polyethylene oxide and the like, higher fatty acids such as stearic acid and behenic acid, and higher fatty acid amides such as stearic acid amide, oleic acid amide, N-methyl stearic acid amide, erucic acid amide, and methylol behen. Acid amide, methylol stearic acid amide, methylene bis stearic acid amide, ethylene bis stearic acid amide, etc., as higher fatty acid anilide, for example, stearic acid anilide, linoleic acid anilide and the like are aromatic amines. The cetyl iodide, e.g. Asetotoruijido etc., although each illustrated, it is possible to improve the blocking without affecting the adhesiveness by using the emulsion particles of stearic acid amide in the higher aliphatic amides.
[0057]
Examples of the hollow particles used in the under layer in the present invention include high molecular compounds such as acrylic polymers and vinylidene chloride polymers.
[0058]
In order to improve the adhesive strength, a tackifier can be added to the heat-sensitive adhesive layer according to the present invention. Specific examples of tackifiers used in the present invention include terpene resins, aliphatic petroleum resins, aromatic petroleum resins, coumarone indene resins, styrene resins, phenol resins, terpene phenol resins, rosin derivative resins, and the like. It is done. These tackifiers are used in a mixture of 200 parts or less, preferably 20 to 150 parts, per 100 parts of the thermoplastic resin. When the added part of the tackifier exceeds 200 parts, blocking tends to occur.
[0059]
In the heat-sensitive adhesive layer according to the present invention, fillers and the like can be added within a range that does not interfere with the object of the present invention. For example, aluminum, zinc, calcium, magnesium, barium, titanium and other carbonates, oxides, water Inorganic pigments containing oxides, sulfates, etc. and viscosity such as natural silica, zeolite, kaolin, calcined kaolin, starch, styrene resin, polyolefin resin, melamine resin, acrylic resin, paraffin, natural wax, synthetic wax, etc. It can be used.
[0060]
The heat-sensitive pressure-sensitive adhesive layer according to the present invention includes an aqueous polymer binder such as polyvinyl alcohol or polyvinyl acetate for the purpose of increasing the adhesion between the heat-sensitive pressure-sensitive adhesive layer and the support or the cohesive force in the heat-sensitive pressure-sensitive adhesive layer. Oxidized starch, etherified starch, cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose, casein, gelatin, sodium alginate and the like can be added. The mixing ratio of the aqueous polymer binder is added within a range that does not impair the original adhesive strength of the heat-sensitive adhesive sheet. Specifically, it is 30% by weight or less, more preferably 10%, based on the total solid content of the heat-sensitive adhesive layer. It is used in the range of weight percent or less.
[0061]
Various additives such as hardeners, preservatives, dyes, UV absorbers, antioxidants, pH adjusters, antifoaming agents, etc. are added to the heat-sensitive adhesive layer according to the present invention as necessary in addition to the above components. can do.
[0062]
The base paper preferably used for the support according to the present invention is composed mainly of wood pulp and filler. Wood pulp includes chemical pulps such as LBKP and NBKP, mechanical pulps such as GP, PGW, RMP, TMP, CTMP, CMP, and CGP, and pulps such as waste paper pulp such as DIP. , Binder, sizing agent, fixing agent, yield improver, cationizing agent, paper strength enhancer, etc. are mixed using one or more kinds of additives, long net paper machine, circular net paper machine, twin wire paper machine, etc. The support can be produced with various devices, and can be made in an acidic, neutral or alkaline paper. The base paper may be subjected to on-machine treatment with a calender device composed of a metal roll and a synthetic resin roll. At that time, off-machine processing may be performed, and after processing, the flatness may be controlled by further performing calendar processing with a machine calendar, a super calendar, or the like.
[0063]
Examples of the filler contained in the base paper include light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, satin white, aluminum silicate, diatomaceous earth, calcium silicate, White inorganic pigments such as magnesium silicate, synthetic silica, aluminum hydroxide, alumina, lithopone, zeolite, magnesium carbonate, magnesium hydroxide, styrene plastic pigment, acrylic plastic pigment, polyethylene, microcapsule, urea resin, melamine resin Such organic pigments can be mentioned.
[0064]
Examples of the sizing agent contained in the base paper include a rosin sizing agent for acidic papermaking, a modified rosin sizing agent for neutral papermaking, AKD, ASA, and a cationic polymer sizing agent.
[0065]
As the support according to the present invention, general paper such as glassine paper, art paper, coated paper, cast paper, and the like can be used. Fillers, sizing agents, paper strength enhancers, dyes, etc., raw materials usually used in papermaking Can be used as needed. Plastic sheets such as polyethylene, polypropylene, polyethylene terephthalate, and polyamide, and synthetic paper or nonwoven fabric made of these synthetic fibers, or laminated paper in which synthetic resin is laminated on one side or both sides, metal foil, or metal foil and paper, It is also possible to use vapor-deposited paper, an opaque sheet subjected to hologram processing, a bonded product with a synthetic resin film, mica paper, glass paper, and the like.
[0066]
The heat-sensitive adhesive layer according to the present invention is a blade coater, a gravure coater, a gravure offset coater, a bar coater, a roll coater, a knife coater, an air knife coater, a comma coater, a U comma coater, which are usually used for paper coating. AKKU coater, smoothing coater, micro gravure coater, reverse roll coater, 4 or 5 roll coater, dip coater, falling curtain coater, slide coater, die coater, etc., or various printing machines such as flexo, letterpress, gravure, offset Used for coating and printing on the support.
[0067]
The drying conditions at the time of coating or printing on the support must be such that the solid plasticizer used does not melt. As a means for drying, in addition to hot air drying, a drying method using a heat source using infrared rays, microwaves, and high frequencies can be used.
[0068]
The coating amount of the heat-sensitive adhesive layer is usually 2 to 50 g / m in dry coating amount.², Preferably 5 to 35 g / m²It is applied in the range of The coating amount of the heat-sensitive adhesive layer is 2 g / m²When it is less than this, sufficient adhesion cannot be obtained when performing adhesion by heating. 50 g / m²Exceeding this is not economically preferable because the adhesive function is saturated.
[0069]
In the present invention, there may be a heat-sensitive recording layer. The leuco dye and developer for the thermal recording layer used in the present invention are not particularly limited as long as they are generally used for thermal recording paper.
[0070]
Specific examples of basic leuco dyes include, for example, fluorane compounds, triarylmethane compounds, spiro compounds, diphenylmethane compounds, thiazine compounds, lactam compounds, fluorene compounds, and the like. It is preferable that the absorption spectrum has at least one maximum absorption wavelength between 550 and 1000 nm.
[0071]
Of these, examples of the fluorane compound include 3-diethylamino-6-methyl-7-anilinofluorane, 3-dibutylamino-6-methyl-7-anilinofluorane, and 3- (N-methyl-N-cyclohexyl). Amino) -6-methyl-7-anilinofluorane, 3- (N-ethyl-N-isopentylamino) -6-methyl-7-anilinofluorane, 3- (N-isobutyl-N-ethylamino) ) -6-Methyl-7-anilinofluorane, 3- [N-ethyl-N- (3-ethoxypropyl) amino] -6-methyl-7-anilinofluorane, 3- (N-ethyl-N) -Hexylamino) -6-methyl-7-anilinofluorane, 3-dipentylamino-6-methyl-7-anilinofluorane, 3- (N-methyl-N-propylamino) -6-me Ru-7-anilinofluorane, 3- (N-ethyl-N-tetrahydrofurylamino) -6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7- (p-chloroanilino) fluorane 3-diethylamino-6-methyl-7- (p-fluoroanilino) fluorane, 3- (p-toluidinoethylamino) -6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl -7- (p-toluidino) fluorane, 3-diethylamino-7- (3,4-dichloroanilino) fluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane, 3-diethylamino-6-chloro- 7-ethoxyethylaminofluorane, 3-diethylamino-6-chloro-7-anilinofluorane, 3-diethylamino-7-pheny Fluoran, 3- (p-preparative Luigi Bruno ethylamino) -6-methyl-7-phenethyl fluoran and the like.
[0072]
Examples of tolylmethane compounds include 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide (also known as crystal violet lactone or CVL) and 3,3-bis (p-dimethylaminophenyl). ) Phthalide, 3- (p-dimethylaminophenyl) -3- (1,2-dimethylaminoindol-3-yl) phthalide, 3- (p-dimethylaminophenyl) -3- (2-methylindole-3- Yl) phthalide, 3- (p-dimethylaminophenyl) -3- (2-phenylindol-3-yl) phthalide, 3,3-bis (1,2-dimethylindol-3-yl) -5-dimethylamino Phthalide, 3,3-bis (1,2-dimethylindol-3-yl) -6-dimethylaminophthalide, 3,3-bis (9- Rucarbazol-3-yl) -5-dimethylaminophthalide, 3,3- (2-phenylindol-3-yl) -5-dimethylaminophthalide, 3-p-dimethylaminophenyl-3- (1- Methylpyrrol-2-yl) -6-dimethylaminophthalide and the like.
[0073]
Furthermore, examples of the spiro compound include 3-methylspirodinaphthopyran, 3-ethylspirodinaphthopyran, 3,3′-dichlorospirodinaphthopyran, 3-benzylspirodinaphthopyran, 3-propylspirobenzopyran. , 3-methylnaphtho- (3-methoxybenzo) spiropyran, 1,3,3-trimethyl-6-nitro-8′-methoxyspiro (indoline-2,2′-benzopyran), N-halophenyl-leucooramine, 4,4-bis-dimethylaminophenylbenzhydrylbenzyl ether, N-2,4,5-trichlorophenylleucooramine, and the like, as thiazine compounds, for example, benzoylleucomethylene blue, p-nitrobenzoyl leucomethylene blue, etc. Examples of the lactam compound include rhodamine B anilinolactam and rhodamine Bp-chloroanilinolactam. Examples of the fluorene compound include 3,6-bis (dimethylamino) fluorene spiro (9,3 '). -6′-dimethylaminophthalide, 3,6-bis (dimethylamino) fluorene spiro (9,3 ′)-6′-pyrrolidinophthalide, 3-dimethylamino-6-diethylaminofluorene spiro (9,3 ′) ) -6'-pyrrolidinophthalide and the like. Further, as a color basic leuco dye, 3-diethylamino-6-methyl-7-chlorofluorane, 3-cyclohexylamino-6-chlorofluorane, 3-diethylamino-benzo [α] fluorane, 3-dibutylamino-benzo [α ] Fluoran, 3-diethylamino-7-chlorofluorane, 3-diethylamino-7-methylfluorane, 3-N-ethyl-N-isoamylamino-benzo [α] fluorane, 3-N-ethyl-Np- Methylphenylamino-7-methylfluorane, 3-diethylamino-6,8-dimethylfluorane, 3-dibutylamino-6-methyl-7-bromofluorane, 3,6-bis (diethylaminofluorane) -γ- (4′-nitro) anilinolactam, bis (1-n-butyl-2-methylindole-3-i) ) Phthalide, bis (1-ethyl-2-methylindol-3-yl) phthalide, 3- (4-diethylaminophenyl) -3- (1-ethyl-2-methylindolyl-3-yl) phthalide, 3- (4-Diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindolyl-3-yl) -4-azaphthalide, 3- (4-diethylaminophenyl) -3- (1-methyl-2) -Methylindolyl-3-yl) phthalide, 3- (4-diethylamino-2-methylphenyl) -3- (1-ethyl-2-methylindolyl-3-yl) phthalide, 3,3-bis (4 -Dimethylaminophenyl) -6-diethylaminophthalide, 3,7-bis (4-dimethylamino) -10-benzoylphenothiazine, 3,3-bis (4-diethylamino- 6-ethoxyphenyl) -4-azaphthalide, 3-diethylamino-7-dianilinofluorane, 3-N-ethyl-N-4-methylphenylamino-7-N-methylanilinofluorane, 3-diethylamino-7 -N-dibenzylaminofluorane, 3,6-dimethoxyfluorane, 3,6-dibutoxyfluorane, 3'-methoxy-4'-lanoxyphenyl-2-cytyrylquinoline, 2 ', 4'-dioct Xylphenyl-2-cytyrylquinoline and the like.
[0074]
Specific examples of the developer are not particularly limited as long as they are generally used for pressure-sensitive recording paper and heat-sensitive recording paper, but bis (3-allyl-4-hydroxyphenyl) sulfone, α-naphthol, β-naphthol, p-octylphenol, 4-t-octylphenol, pt-butylphenol, p-phenylphenol, 1,1-bis (p-hydroxyphenyl) propane, 2,2-bis (p-hydroxyphenyl) propane (Alternative name: Bisphenol A or BPA), 2,2-bis (p-hydroxyphenyl) butane, 1,1-bis (p-hydroxyphenyl) cyclohexane, 4,4'-thiobisphenol, 4,4'-cyclohexylene Dendiphenol, 2,2 '-(2,5-dibromo-4-hydroxyphenyl) propane, 4,4-i Sopropylidenebis (2-t-butylphenol), 2,2′-methylenebis (4-chlorophenol), 4,4′-dihydroxydiphenylsulfone, 4-hydroxy-4′-methoxydiphenylsulfone, 4-hydroxy- 4′-ethoxydiphenylsulfone, 4-hydroxy-4′-isopropoxydiphenylsulfone, 4-hydroxy-4′-butoxydiphenylsulfone, methyl bis- (4-hydroxyphenyl) acetate, bis- (4-hydroxyphenyl) acetic acid Phenolic compounds such as butyl, benzyl bis- (4-hydroxyphenyl) acetate, 2,4-dihydroxy-2′-methoxybenzanilide, benzyl p-hydroxybenzoate, ethyl p-hydroxybenzoate, 4-hydroxyphthalic acid Dibenzyl, 4-hydroxyph Aromatic carboxylic acid derivatives such as dimethyl oxalate, ethyl 5-hydroxyisophthalate, 3,5-di-t-butylsalicylic acid, 3,5-di-α-methylbenzylsalicylic acid, aromatic carboxylic acids or metal salts thereof, etc. Is mentioned.
[0075]
Examples of the binder used in the heat-sensitive recording layer of the present invention include starches, cellulose derivatives such as hydroxyethylcellulose, methylcellulose, ethylcellulose, and carboxymethylcellulose; proteins such as casein and gelatin; aqueous solutions such as saccharose such as oxidized starch and ester compound starch. Natural polymer compound, polyvinyl alcohol, modified polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, sodium polyacrylate, acrylic amide-acrylic ester copolymer, acrylic amide-acrylic ester-methacrylic acid terpolymer , Water-soluble synthetic polymer compounds such as styrene-maleic anhydride copolymer alkali salt, latex, polyacrylamide, styrene-maleic anhydride copolymer, and latex Water-soluble adhesive resin such as alkali salt of ethylene-maleic anhydride copolymer, polyvinyl acetate, polyurethane, polyacrylic ester, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, methyl acrylate-butadiene copolymer Examples thereof include latex such as a polymer, an acrylonitrile-butadiene-acrylic acid copolymer, and an ethylene-vinyl acetate copolymer.
[0076]
In order to further improve the sensitivity of the thermosensitive recording layer, as sensitizers, waxes such as N-hydroxymethyl stearamide, stearamide, and palmitic acid amide, naphthol derivatives such as 2-benzyloxynaphthalene, p -Biphenyl derivatives such as benzylbiphenyl and 4-allyloxybiphenyl, 1,2-bis (3-methylphenoxy) ethane, 2,2'-bis (4-methoxyphenoxy) diethyl ether, bis (4-methoxyphenyl) ether Polyether compounds such as diphenyl carbonate, dibenzyl oxalate, and carbonic acid or oxalic acid diester derivatives such as di (p-chlorobenzyl) oxalate can be added.
[0077]
Examples of the pigment used in the heat-sensitive recording layer include diatomaceous earth, talc, kaolin, calcined kaolin, calcium carbonate, magnesium carbonate, titanium oxide, zinc oxide, silicon oxide, aluminum hydroxide, urea-formalin resin and the like.
The purpose of providing an intermediate layer for improving heat-sensitive color development under the heat-sensitive recording layer, i.e., on the support and preventing dregs due to printing, or for imparting color stains and water resistance to the heat-sensitive recording layer. It is possible to provide a protective layer.
As a coating method for providing a thermal recording layer, an intermediate layer, and a protective layer, blade coating method, gravure coating method, gravure offset coating method, bar coating method, roll coating method, knife coating method, air knife coating method, comma coating method, U Comma coating method, AKKU coating method, smoothing coating method, micro gravure coating method, reverse roll coating method, four or five roll coating method, dip coating method, falling curtain coating method, slide coating method, die coating method, etc. The following coating methods are available.
[0078]
【Example】
  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, the content of this invention is not restricted to an Example. All parts and percentages shown below are on a weight basis. Further, the value indicating the coating amount is the coating amount after drying unless otherwise specified.In addition, in the Example shown below, Examples 1-7 are examples corresponded to the reference example which does not belong to the scope of the present invention.
[0079]
<Example 1>
[Preparation of Composite Fine Particle Dispersion Liquid [A Liquid] of Thermoplastic Resin and Plasticizer]
A thermoplastic resin (glass transition point 10 ° C., average molecular weight 450,000) obtained by graft polymerization of metamethyl acrylate in a proportion of 25% by weight with natural rubber as the main component is an organic solvent of toluene / ethyl acetate (toluene: acetic acid). It was completely dissolved in ethyl = 8: 2) so as to have a solid content of 50%. Subsequently, the liquid plasticizer dioctyl adipate was added to 100 parts of the thermoplastic solution so as to have a formulation ratio of 40 parts, and the mixture was stirred and mixed until it was sufficiently compatible. Separately, 50 parts of the thermoplastic resin and liquid plasticizer solution were added to 100 parts of polyvinyl alcohol prepared to 8%, and the average particle size was 15.0 μm under the condition that the liquid temperature was controlled at 15 ° C. The mixture was emulsified and dispersed using a homomixer to obtain an O / W emulsion dispersion. The emulsion dispersion was heated to 80 ° C. and stored until the organic solvent was completely evaporated. After the organic solvent is completely vaporized, the mixture is allowed to stand until the liquid temperature reaches room temperature, and then water is added so that the total solid content is 30%, and a composite fine particle dispersion of thermoplastic resin and plasticizer [liquid A] Was prepared.
[0080]
[Preparation of heat-sensitive adhesive layer coating solution [Liquid B]]
A heat-sensitive adhesive layer coating solution [Liquid B] was prepared by mixing 132.5 parts of the composite fine particle dispersion [Liquid A] and 15.0 parts of terpenephenol 50% dispersion as a tackifier.
[0081]
[Production of Dye Dispersion Liquid [C Liquid]]
Average mixture of 1.0 part of 3-dibutylamino-6-methyl-7-anilinofluorane and 1.0 part of polyvinyl alcohol 10% aqueous solution and 2.0 parts of water using a sand grinder The liquid [C] was pulverized and dispersed so that the diameter was 0.7 to 1.0 μm.
[0082]
[Generation of developer solution [D solution]]
A mixture of 3.0 parts of 4-hydroxy-4'-isopropoxydiphenylsulfone, 1.0 part of silica, 4.0 parts of polyvinyl alcohol 10% aqueous solution and 10.0 parts of water was averaged using a sand grinder. [D liquid] was produced by pulverization and dispersion so that the particle size was 3 μm or less.
[0083]
[Generation of thermosensitive liquid [E liquid]]
The liquid mixture having a formulation ratio of 4.0 parts of the dye dispersion liquid [C liquid], 18.0 parts of the developer liquid [D liquid], and 3.0 parts of water is sufficiently stirred, and the heat sensitive liquid [E Liquid] was produced.
[0084]
[Formation of silica dispersion [F liquid]]
A mixture of 1.0 part of silica and 1.0 part of polyvinyl alcohol 10% aqueous solution and 2.0 parts of water is pulverized and dispersed using a sand grinder so that the average particle size is 3.0 μm or less. To produce [F solution].
[0085]
[Generation of protective layer solution [G solution]]
4.0 parts of the silica dispersion [F liquid], 10.0 parts of a 10% polyvinyl alcohol aqueous solution, 1.0 part of a 30% zinc stearate dispersion (Z-730, manufactured by Chukyo Yushi), 12 parts of polyamide epichlorohydrin A mixed solution having a formulation ratio of 3.2 parts of a 5% solution and 5.8 parts of water was sufficiently stirred to produce a protective layer solution [solution G].
[0086]
[Production of heat-sensitive adhesive material]
Using a wire bar on one side of the support, heat sensitive liquid [E liquid] has a basis weight of 50 g / m.²The weight of dye is about 0.5g / m on high quality paper²And the protective layer solution [G solution] has a dry weight of 3.5 g / m.²Then, coating and drying were performed sequentially, and a calendar process was performed to make the surface 2000 s with a Oken type smoothness meter. Furthermore, the dry weight of the heat-sensitive adhesive layer coating solution [Liquid B] prepared by preparing the heat-sensitive adhesive layer coating solution on the back surface is 12 g / m.²Coating and drying were performed to obtain a heat-sensitive adhesive material of the present invention.
[0087]
<Example 2>
Acrylic acid instead of the thermoplastic resin (glass transition point 10 ° C., average molecular weight 450,000) obtained by graft polymerization of methyl methacrylate with a proportion of 25% by weight based on the natural rubber used in Example 1 The heat-sensitive adhesive material of the present invention was obtained in the same manner except that the ester resin (glass transition point 10 ° C., average molecular weight 500,000) was changed.
[0088]
<Example 3>
Styrene acrylic instead of the thermoplastic resin (glass transition point 10 ° C., average molecular weight 450,000) obtained by graft polymerization of metamethyl acrylate with a proportion of 25% by weight based on natural rubber used in Example 1 A heat-sensitive adhesive material of the present invention was obtained in the same manner except that the resin (glass transition point 5 ° C., average molecular weight 500,000) was changed.
[0089]
<Example 4>
Ethylene acetic acid instead of the thermoplastic resin (glass transition point 10 ° C., average molecular weight 450,000) obtained by graft polymerization of methyl methacrylate with a proportion of 25% by weight based on natural rubber used in Example 1 The heat-sensitive adhesive material of the present invention was obtained in the same manner except that the resin was changed to a vinyl resin (glass transition point 25 ° C., average molecular weight 500,000).
[0090]
<Example 5>
Acrylic acid instead of the thermoplastic resin (glass transition point 10 ° C., average molecular weight 450,000) obtained by graft polymerization of methyl methacrylate with a proportion of 25% by weight based on the natural rubber used in Example 1 The heat-sensitive adhesive of the present invention was similarly used except that the resin was changed to an ester resin (glass transition point 10 ° C., average molecular weight 500,000), and the composite fine particles were further adjusted to have an average particle size of 15.0 μm to 3.0 μm. Obtained material.
[0091]
<Example 6>
Acrylic acid instead of the thermoplastic resin (glass transition point 10 ° C., average molecular weight 450,000) obtained by graft polymerization of methyl methacrylate with a proportion of 25% by weight based on the natural rubber used in Example 1 The heat-sensitive adhesive material of the present invention was obtained in the same manner except that the ester resin (glass transition point -65 ° C, average molecular weight 500,000) was changed.
[0092]
<Example 7>
Acrylic acid instead of the thermoplastic resin (glass transition point 10 ° C., average molecular weight 450,000) obtained by graft polymerization of methyl methacrylate with a proportion of 25% by weight based on the natural rubber used in Example 1 The heat-sensitive adhesive material of the present invention was obtained in the same manner except that the ester resin (glass transition point 10 ° C., average molecular weight 250,000) was changed.
[0093]
<Example 8>
Acrylic acid instead of the thermoplastic resin (glass transition point 10 ° C., average molecular weight 450,000) obtained by graft polymerization of methyl methacrylate with a proportion of 25% by weight based on the natural rubber used in Example 1 The same procedure was performed except that the ester resin was changed to 2-ethylhexyl acrylate (glass transition point -60 ° C., average molecular weight 250,000), and the average particle size of the composite fine particles was adjusted from 15.0 μm to 3.0 μm. Thus, the heat-sensitive adhesive material of the present invention was obtained.
[0094]
<Example 9>
[Preparation of composite fine particle dispersion [H] of thermoplastic resin and plasticizer]
The thermoplastic resin 2-ethylhexyl acrylate (glass transition point -60 ° C., average molecular weight 250,000) is completely dissolved in a toluene / ethyl acetate organic solvent (toluene: ethyl acetate = 8: 2) so as to have a solid content of 50%. I let you. Next, the solid plasticizer compound 30 (melting point: 73.0 ° C.) was completely dissolved in an organic solvent of toluene / ethyl acetate (toluene: ethyl acetate = 8: 2) so as to have a solid content of 50%. Further, the mixture was stirred and mixed until dissolved in 70 parts of the thermoplastic solution. Separately, 50 parts of the thermoplastic resin and liquid plasticizer solution were added to 100 parts of polyvinyl alcohol prepared to 8%, and the average particle size was 3.0 μm under the condition that the liquid temperature was controlled at 15 ° C. The mixture was emulsified and dispersed using a homomixer to obtain an O / W emulsion dispersion. The emulsion dispersion was heated to 80 ° C. and stored until the organic solvent was completely evaporated. After the organic solvent is completely evaporated, the mixture is allowed to stand until the liquid temperature reaches room temperature, and then water is added so that the total solid content becomes 25.0%, and a composite fine particle dispersion of thermoplastic resin and plasticizer [H Liquid] was prepared.
[0095]
[Preparation of heat-sensitive adhesive layer coating solution [I solution]]
A heat-sensitive adhesive layer coating liquid [I liquid] was prepared by mixing 125.0 parts of the composite fine particle dispersion [H liquid] and 15.0 parts of terpenephenol 50% dispersion as a tackifier.
[0096]
[Production of heat-sensitive adhesive material]
Using a wire bar on one side of the support, heat sensitive liquid [E liquid] has a basis weight of 50 g / m.²The weight of dye is about 0.5g / m on high quality paper²And the protective layer solution [G solution] has a dry weight of 3.5 g / m.²Then, coating and drying were performed sequentially, and a calendar process was performed to make the surface 2000 s with a Oken type smoothness meter. Furthermore, the dry weight of the heat-sensitive adhesive layer coating liquid [I liquid] prepared by preparing the heat-sensitive adhesive layer coating liquid on the back surface is 12 g / m.²Coating and drying were performed to obtain a heat-sensitive adhesive material of the present invention.
[0097]
<Example 10>
The heat-sensitive adhesive material of the present invention was obtained in the same manner except that the plasticizer compound 30 (melting point 73 ° C.) used in Example 9 was changed to compound 6 (melting point 158 ° C.).
[0098]
<Example 11>
A heat-sensitive adhesive material of the present invention was obtained in the same manner except that the plasticizer compound 30 (melting point 73 ° C.) used in Example 9 was changed to the compound 8 (melting point 129 ° C.).
[0099]
<Example 12>
The heat-sensitive adhesive material of the present invention was obtained in the same manner except that the plasticizer compound 30 (melting point 73 ° C.) used in Example 9 was changed to the compound 18 (melting point 135 ° C.).
[0100]
<Example 13>
A heat-sensitive adhesive material of the present invention was obtained in the same manner except that the plasticizer compound 30 (melting point 158 ° C.) used in Example 9 was changed to compound 4 (melting point 65 ° C.).
[0101]
<Example 14>
The heat-sensitive adhesive material of the present invention was obtained in the same manner except that the plasticizer compound 30 (melting point 73 ° C.) used in Example 9 was changed to compound 2 (melting point 105 ° C.).
[0102]
<Example 15>
The heat-sensitive adhesive material of the present invention was obtained in the same manner except that the plasticizer compound 30 (melting point 73 ° C.) used in Example 9 was changed to compound 1 (melting point 77 ° C.).
[0103]
<Example 16>
A heat-sensitive adhesive material of the present invention was obtained in the same manner except that the compound 30 (melting point: 73 ° C.), which was a plasticizer used in Example 9, was changed to the compound 11 (melting point: 104 ° C.).
[0104]
<Example 17>
The heat-sensitive adhesive material of the present invention was obtained in the same manner except that the plasticizer compound 30 (melting point 73 ° C.) used in Example 9 was changed to the compound 17 (melting point 87 ° C.).
[0105]
<Example 18>
[Preparation of under solution [J solution]]
Hollow particle emulsion (hollow rate 50%, solid content 25%) 4.0 parts, styrene butadiene latex (solid content 50%) 0.4 parts, polyvinyl alcohol (solid content 10% aqueous solution) 1.0 part and water 1. Underpart [J liquid] was prepared by thoroughly mixing 1 part.
[0106]
[Production of heat-sensitive adhesive material]
Using a wire bar on one side of the support, heat sensitive liquid [E liquid] has a basis weight of 50 g / m.²The weight of dye is about 0.5g / m on high quality paper²And the protective layer solution [G solution] has a dry weight of 3.5 g / m.²Then, coating and drying were performed sequentially, and a calendar process was performed to make the surface 2000 s with a Oken type smoothness meter. Furthermore, the dry weight of under liquid [J liquid] is 3g / m on the back side.²Then, the heat-sensitive adhesive layer coating solution used in Example 15 was dried at a weight of 12 g / m.²Coating and drying were performed to obtain a heat-sensitive adhesive material of the present invention.
[0107]
<Comparative Example 1>
[Preparation of thermoplastic resin emulsion dispersion [liquid K]]
A thermoplastic resin (glass transition point 10 ° C., average molecular weight 450,000) obtained by graft polymerization of metamethyl acrylate in a proportion of 25% by weight with natural rubber as the main component is an organic solvent of toluene / ethyl acetate (toluene: acetic acid). It was completely dissolved in ethyl = 8: 2) so as to have a solid content of 50%. Separately, 50 parts of the thermoplastic resin solution was added to 100 parts of polyvinyl alcohol prepared to 8%, and the average particle size was 15.0 μm under the condition that the liquid temperature was controlled at 15 ° C. Emulsion dispersion was performed using a homomixer to obtain an O / W emulsion dispersion. The emulsion dispersion was heated to 80 ° C. and stored until the organic solvent was completely evaporated. After the organic solvent is completely vaporized, the mixture is allowed to stand until the liquid temperature reaches room temperature, and then water is added so that the total solid content is 25%, and a composite fine particle dispersion of thermoplastic resin and plasticizer [liquid K] Was prepared.
[0108]
[Production of Solid Plasticizer Dispersion [Liquid L]]
A mixture having a formulation ratio of 10 parts of solid plasticizer compound 30 and 10 parts of polyvinyl alcohol 10% and 7.5 parts of water is adjusted using a sand grinder so that the average particle size becomes 0.7 to 1.0 μm. After pulverizing and dispersing, [Liquid L] was produced.
[0109]
[Preparation of heat-sensitive adhesive layer coating solution [M solution]]
125 parts of the thermoplastic resin emulsion dispersion [Liquid K], 100 parts of the solid plasticizer dispersion [Liquid L] and 20 parts of a 50% terpene phenol dispersion as a tackifier are mixed together, A heat-sensitive adhesive layer coating solution [M solution] was prepared.
[0110]
[Production of heat-sensitive adhesive material]
Using a wire bar on one side of the support, heat sensitive liquid [E liquid] has a basis weight of 50 g / m.²The weight of dye is about 0.5g / m on high quality paper²And the protective layer solution [G solution] has a dry weight of 3.5 g / m.²Then, coating and drying were performed sequentially, and a calendar process was performed to make the surface 2000 s with a Oken type smoothness meter. Furthermore, the dry weight of the heat-sensitive adhesive layer coating liquid [M liquid] prepared by preparing the heat-sensitive adhesive layer coating liquid on the back surface is 12 g / m.²Coating and drying were performed to obtain a heat-sensitive adhesive material of the present invention.
[0111]
For the heat-sensitive adhesive materials obtained in the above Examples and Comparative Examples, the tackiness and blocking resistance were evaluated by the following test methods. In addition, the measurement of the particle diameter was performed using the particle size distribution meter LA-700 made from a dug mill.
[0112]
<Adhesiveness>
The heat-sensitive adhesive material of the present invention is cut into a 4.0 cm × 9.0 cm rectangle, and a head condition of 0.54 mJ / dot, a printing speed of 4 ms / line, and a platen pressure using a thermal printing apparatus TH-PMD manufactured by Okura Electric Co., Ltd. The heat-sensitive adhesive layer is thermally activated under the condition of 6 kgf / line. Subsequently, it adheres to a to-be-adhered body (polyolefin wrap) in the longitudinal direction with a rubber roller of 2 kg under pressure, and after 1 minute, it is peeled under conditions of a peeling angle of 180 ° C. and a peeling speed of 300 mm / min. The resistance value of the adhesive strength at that time was indicated by a numerical value. The unit is gf / 40 mm. This test was performed in a low temperature environment (0 ° C., 15%), a normal temperature environment (20 ° C., 65%), and a high temperature environment (40 ° C., 80%).
[0113]
<Blocking resistance>
The surface of the heat-sensitive recording layer of the same sample is brought into contact with the surface of the heat-sensitive adhesive layer and 2 kg / cm.²The sample was peeled off after standing at room temperature for 24 hours under the pressure of 50 ° C. and Dry, and the blocking resistance at that time was evaluated according to the rank shown in Table 8 below. The evaluation results of tackiness and blocking resistance are shown in [Table 9] below.
[0114]
[Table 8]

[0115]
[Table 9]

[0116]
【The invention's effect】
The heat-sensitive adhesive material of the present invention has a high adhesive force to polyolefin while maintaining the adhesive force (without reducing it), and is excellent in blocking resistance. Moreover, according to the sticking method of this invention, the said thermosensitive adhesive material can be adhered to polyolefin wrap with high adhesive force. Furthermore, according to the manufacturing method sticking method of the thermosensitive adhesive concerning this invention, a predetermined thermosensitive adhesive can be provided in a simple process.

Claims (18)

The thermoplastic resin and plasticizer are dissolved in an organic solvent, then emulsified and dispersed, and then the organic solvent is completely vaporized so that the heat-sensitive adhesive mainly comprises fine particles of a thermoplastic resin and a plasticizer combined. Na to impart heat-sensitive adhesive layer on a support made it is,
The said thermoplastic resin consists of 2-ethylhexyl acrylate, The heat-sensitive adhesive material characterized by the above-mentioned . After the organic solvent dissolving the thermoplastic resin and a plasticizer, emulsified and dispersed, and then the thermoplastic resin and the plasticizer mainly of fine particles and the tackifier complexed with to completely vaporize the organic solvent sensitive Ri Na to impart heat-sensitive adhesive layer made of sexual adhesive on a support,
The said thermoplastic resin consists of 2-ethylhexyl acrylate, The heat-sensitive adhesive material characterized by the above-mentioned .   3. The heat-sensitive adhesive material according to claim 1, wherein a volume average particle diameter of the fine particles is 0.5 μm to 10.0 μm.   4. The thermoplastic resin according to claim 1, wherein the thermoplastic resin is at least one thermoplastic resin selected from an acrylic ester copolymer, a styrene acrylic copolymer, and an ethylene vinyl acetate copolymer. The heat-sensitive adhesive material described in 1.   The heat-sensitive adhesive material according to claim 1, wherein the thermoplastic resin has a glass transition point of 0 ° C. to −70 ° C.   6. The thermosensitive adhesive material according to claim 1, wherein the thermoplastic resin has an average molecular weight of 100,000 to 300,000. The heat-sensitive adhesive material according to claim 2, wherein the tackifier contains terpene phenol .   The heat-sensitive adhesive material according to claim 1, wherein the plasticizer is a solid plasticizer.   The heat-sensitive adhesive material according to claim 8, wherein the solid plasticizer has a melting point of 50C to 120C.   The heat-sensitive adhesive material according to claim 9, wherein the solid plasticizer exhibits a solid state at room temperature and does not solidify again when stored in a temperature environment at 20 ° C after being liquefied by heating.   The heat-sensitive adhesive material according to claim 10, wherein the solid plasticizer contains at least one selected from a hindered phenol compound, a benzotriazole compound, and a sulfonamide compound. The heat-sensitive adhesive material according to claim 11, wherein the solid plasticizer is a hindered phenol compound represented by the following structural formula.

The heat-sensitive adhesive material according to claim 11, wherein the solid plasticizer is a benzotriazole compound represented by the following structural formula.

The heat-sensitive adhesive material according to claim 11, wherein the solid plasticizer is a sulfonamide compound represented by the following structural formula.

  The heat-sensitive adhesive material according to any one of claims 1 to 14, wherein an under layer mainly composed of hollow particles is provided between the heat-sensitive adhesive layer and the support.   The heat-sensitive adhesive material according to any one of claims 1 to 15, wherein a heat-sensitive recording layer mainly comprising a leuco dye and a developer is provided on the heat-sensitive adhesive layer.   A method of sticking the heat-sensitive adhesive material according to any one of claims 1 to 16 to an adherend, wherein the heat-sensitive adhesive material is heated with a thermal head from the surface of the heat-sensitive adhesive layer side, A method for attaching a heat-sensitive adhesive material, comprising: activating a heat-sensitive adhesive to develop an adhesive force, and attaching the heat-sensitive adhesive material exhibiting the adhesive force to an adherend. A method for producing a thermosensitive adhesive mainly comprising fine particles of a thermoplastic resin and a plasticizer, wherein the dispersion is obtained by mixing, emulsifying and dispersing an organic solvent solution of a thermoplastic resin and an organic solvent solution of a plasticizer. from the liquid, the organic solvent was completely vaporized form fine particles that combines with the plasticizer and the thermoplastic resin, then, becomes a mixture of organic solvent dispersion of tackifier,
The said thermoplastic resin consists of 2-ethylhexyl acrylate , The manufacturing method of the thermosensitive adhesive characterized by the above-mentioned .