JP4264482B2

JP4264482B2 - Fire extinguisher, water for fire extinguishing and fire extinguishing method

Info

Publication number: JP4264482B2
Application number: JP2000091579A
Authority: JP
Inventors: 恵三樫木; 晃史郎栄; 昌利住谷; 茂小松; 学士丸山; 岩峰王
Original assignee: Kohjin Holdings Co Ltd
Current assignee: Kohjin Holdings Co Ltd
Priority date: 1999-10-20
Filing date: 2000-03-29
Publication date: 2009-05-20
Anticipated expiration: 2020-03-29
Also published as: JP2001187165A

Description

【０００１】
【発明の属する技術分野】
本発明は、被消火物等の表面に消火用の水を保持させることのできる消火剤、消火用水及びこれを使用する消火方法に関するものである。
【０００２】
【従来の技術】
従来より消火には「水」が主に使用されている。わが国では水資源が比較的豊富でかつ上水道が普及しているため、消火には上水道が主として使用され、防火水槽や河川の水が補助的に用いられている。しかし、阪神・淡路大震災のような大地震などによって水道管の破裂や防火水槽の損壊などが生じた場合には限られた水で消火しなければならない。また、山林の火災などの場合も同様である。これらの場合の消火方法として、例えば、消火用の化学薬品を用いるとか砂を掛けるなど方法が採られているが、前者は水に比べて高価であるとか使用に注意が必要であるなどの問題点を有し、後者は重くてかつ流動性が無いため消火地点に容易に送れないなどの問題点を有している。
【０００３】
燃焼物に掛けられた水は、その蒸発潜熱によって燃焼物を着火点又は発火点以下に冷却する作用や酸素の遮断作用などにより消火するが、用いられた水の多くは燃焼物面より流れ落ちてしまうため、効率の悪い結果となっている。消火に使用した水が燃焼物の表面に残留すれば、上記の消火作用がより十分に得られるものと考えられる。
その対策の一つとして、高吸水性ポリマーの使用が研究されている。このポリマーは水に接すると数秒で自量の数百ないし数千倍の量の水を固形化するが、水に溶けている物質等によって固形化が著しく阻害されるとともに紫外線で分解され固形化した水が容易に流失するという欠点がある。また、該ポリマーは消火水とは別個に取扱わなければならないという問題点を有する。また、セルロース誘導体等の熱ゲル化剤と高吸水性樹脂を添加させた薬剤も報告されているが（例えば、特開平１−５６０７０号公報等）、水溶液ではないため消防ポンプ等に付着しその除去が容易でないという問題点があった。
【０００４】
一方、一般家庭の火災発生原因として、天ぷら油火災によるものが、近年ますます増加している傾向がある。都市部の住宅事情を考えると、一般家庭の火災についても甚大な災害の原因となり得ることから、火災の初期段階での確実且つより安全な消火方法を必要とするところである。
従来、広く使用されている消火薬剤として、粉末系の消火薬剤、ガス系の消火薬剤、水系の消火薬剤があるが、天ぷら油火災の場合は油の発火点以下に冷却しないと再着火するため、水系の消火薬剤が好ましいと考えられている。しかし、従来の水系の消火薬剤では、突沸を起こしたり、消火液が高いアルカリ性を示したり、炎が高く上がるなどの問題点を有している。
【０００５】
【発明が解決しようとする課題】
本発明は、これらの点に鑑み、従来の消火水と同様に取扱いができ、かつ、噴射した消火水が燃焼物面に残留する消火剤、消火用水を提供せんとするものである。
更に、天ぷら油火災等の油火災に対しても優れた消火作用を有する消火剤、消火用水を提供せんとするものである。
【０００６】
【課題を解決するための手段】
本発明者らは、消火用の「水」に添加してもその水は常温では液体のままで、粘度も比較的小さく流動性を有し既存の消防ポンプ等で充分に使用でき、燃焼物面で水を多量に含有し固形化し、空気を遮断すると共に冷却効果をも有する。更に油火災に対しても優れた消火作用を持つ物質を求めて種々研究した結果、感温性ポリマーがその目的に達成し得ることを見出して本発明を完成した。
【０００７】
すなわち本発明は、（１）特定の設定温度以下では水溶性で、設定温度以上では水を含んで固形化する感温性ポリマーを含むことを特徴とする消火剤、
（２）感温性ポリマーの固形化が、ハイドロゲルであることを特徴とする上記（１）記載の消火剤、
（３）感温性ポリマーが、水溶性アクリルアミド系ポリマーであることを特徴とする上記（１）及び（２）記載の消火剤、
（４）感温性ポリマーが、Ｎ−イソプロピルアクリルアミドを主成分とするポリマーであることを特徴とする上記（１）〜（３）記載の消火剤、
（５）感温性ポリマーが、Ｎ−イソプロピルアクリルアミド７５〜９９モル％とアクリル酸ナトリウム１〜２５モル％を共重合してなるポリマーであることを特徴とする上記（１）〜（４）記載の消火剤、
（６）上記（１）〜（５）に記載の消火剤を水に溶解することを特徴とする消火用水、
（７）感温性ポリマーのほかに、消火剤、防炎剤並びに必要に応じてこれら薬剤の浸透剤を含むことを特徴とする上記（６）記載の消火用水、
（８）水溶液の粘度が２０〜２０００ｍＰａ・ｓ（３０℃）であることを特徴とする上記（６）及び（７）記載の消火用水、
（９）請求項（６）〜（８）に記載の消火用水を使用することを特徴とする消火方法、
（10）感温性ポリマーを予め所定濃度に溶解した感温性ポリマー水溶液を消火用の水に添加しつつ噴射等することを特徴とする上記（９）記載の消火方法、
を提供するものである。
【０００８】
【発明の実施の形態】
本発明に用いられる感温性ポリマーは、「特定の設定温度（以下感温点と記述する）以下では水溶性で、感温点以上では固形化（水不溶のハイドロゲルとなる）する温度感応性ポリマー」と定義されるものである。
本発明は、この感温性ポリマーを消火剤として消防用の水に添加して、その水溶液が常温時には流動性を有し消火水と同様に従来の消防ポンプ等の消防器具で消火に使用でき、火災物（燃焼物）に噴射又は噴霧したとき、燃焼による熱で水を含んだ状態でゲル化ないしは固形化して燃焼物面に残留し、消火、延焼及び再着火を防止するようにしたものである。
【０００９】
本発明の感温性ポリマーは、例えば、
（１）そのホモポリマーが水中で下限臨界共溶温度を有するビニルモノマー（ａ）と、（ａ）と共重合可能な他のビニルモノマー（ｂ）とを共重合する方法、及び
（２）メチルセルロース、ヒドロキシプロピルセルロースのごとき水中で下限臨界共溶温度を有するポリマーにアクリル酸ナトリウムのようなイオン基を有するビニルモノマーをグラフト重合する方法
などの製法によって得ることができる。上記の製法のうち（１）の方法が、得られるポリマーの感温点を容易に調整できることからより好ましい。
ビニルモノマー（ａ）としては、Ｎ−イソプロピル（メタ）アクリルアミド、Ｎ−ｎ−プロピル（メタ）アクリルアミド、Ｎ，Ｎ−ジエチルアクリルアミド、アクリロイルピペリジン、アクリロイルピロリジン、ビニルカプロラクタム等のＮ−置換アクリルアミド及びその誘導体、メチルビニルエーテル、エチルビニルエーテル等のアルキルビニルエーテル、Ｎ−ビニルイソブチルアミド等のＮ−ビニルアルキルアミドなどが挙げられる。
【００１０】
ビニルモノマー（ｂ）としては、アクリル酸及びその塩（ナトリウム塩、カリウム塩、カルシウム塩等）、２−アクリルアミド−２−プロパンスルホン酸及びその塩（ナトリウム塩、カリウム塩、カルシウム塩等）、Ｎ，Ｎ−ジメチルアミノプロピルアクリルアミド及びその塩（硫酸塩、モノメチル硫酸塩、ジメチル硫酸塩、塩化メチル塩等）、Ｎ，Ｎ−ジメチルアミノエチル（メタ）アクリレート及びその塩（硫酸塩、モノメチル硫酸塩、ジメチル硫酸塩、塩化メチル塩等）等のイオン性基を有するビニルモノマー、アクリルアミド、ジアセトンアクリルアミド、ｔｅｒｔ−ブチルアクリルアミド等のアクリルアミド誘導体、（メタ）アクリル酸メチル、（メタ）アクリル酸エチル、（メタ）アクリル酸ブチル、ヒドロキシエチル（メタ）アクリレート等の（メタ）アクリル酸エステル等が挙げられる。
【００１１】
感温性ポリマーの固形化温度は特に限定されないが、常温ないしは火災現場での温度で、また盛夏時の温度でゲル化しない温度以上とすることが必要である。冬期及び火災現場での温度を考慮して１０〜１４０℃（１００℃以上は、加圧下で測定した値）、好ましくは５０〜１００℃の温度範囲で設定するとよい。
具体的な感温性ポリマーとしては、ビニルモノマー（ａ）としてＮ−イソプロピルアクリルアミドを主成分とし、他のビニルモノマー（ｂ）と共重合させたポリマーが好ましく、特にＮ−イソプロピルアクリルアミド７５〜９９モル％とビニルモノマー（ｂ）としてアクリル酸ナトリウム１〜２５モル％とを共重合させたポリマーが天ぷら油火災、石油ストーブ火災にも優れた消火性能を持つためより好ましい。
【００１２】
本発明では、更に、感温性ポリマーを含んだ消火剤を水に溶解させた消火用水が提供される。
感温性ポリマーの分子量並びに水への溶解濃度については、消火に用いる水溶液の状態でかつ、感温性ポリマーが水溶性を示す温度範囲において、感温性ポリマーを含む水が２０〜２０００ｍＰａ・ｓ（３０の℃）の粘度を有する量であることが望ましい。この範囲より粘度が低い場合、消火用水を十分にハイドロゲル状とすることができず高い消火並びに延焼防止効果を期待できない。また、この範囲より高い粘度の場合、輸送・放水操作が困難となり好ましくない。
感温性ポリマーの種類、分子量等によって異なるが、水に対して０．１〜１０重量％、好ましくは、０．５〜２重量％程度の水溶液とするとよい。濃度が、０．１重量％未満であると熱による固形化が十分でなく、１０重量％を越えると水溶液の粘度が高くなり流動性に乏しくなる場合があり好ましくない。
【００１３】
感温性ポリマーを含む消火用水には、必要に応じて、従来より消火用薬剤として使用されている薬剤を添加することもできる。例えば、燐酸第１アンモニウム、燐酸第２アンモニウムのごとき消火剤、防炎剤や、ジオクチルスルホコハク酸ナトリウムのごとき浸透剤としての界面活性剤等を混合溶解して使用しても何ら差し支えないばかりか、感温性ポリマーの固形化作用により防炎剤等の飛散・流出を防止できるため、より効果的に消火並びに延焼防止を行うことができる。
これら消火剤、防炎剤、浸透剤等は、消火用水に対して０．０５〜５重量％の濃度で使用することが望ましい。濃度が０．０５重量％以下であると防炎剤あるいは浸透剤の効果が乏しく、５重量％以上の添加は感温性ポリマーの析出等を招くため好ましくない。
【００１４】
本発明の消火用水は、そのまま一般的な消火方法と同様の方法で放水し消火に用いることができる。例えば、噴霧状又は水滴状にホースより噴出させて、火炎中で固形化して燃焼物面に落下・付着するようにしてもよく、また、従来の消防ホースで噴射させて燃焼物面で固形化するようにしてもよい。
この他、予め感温性ポリマーの濃厚水溶液を調整しておき、消火時に消火用の水に添加しつつ放水するようにしてもよい。
【００１５】
【実施例及び試験例】
以下に感温性ポリマーの製造例及び消火剤、消火用水の試験例を示すが、本発明はこれらの例に限定されるものではない。なお、以下の例において、特記しない限り％は重量％を示す。
【００１６】
製造例１：感温性ポリマーＡの製造
２Ｌ容量のガラス製セパラブルフラスコに脱塩水１３６０ｇを入れ、Ｎ−イソプロピルアクリルアミド２２２．６ｇを加えて攪拌下溶解した。溶解した溶液を１０℃に冷却した後、２−アクリルアミド−２−メチルプロパンスルホン酸３５．５ｇを加え、攪拌下溶解した。この溶解液の温度を１５℃以下に保ちながら、４８％苛性ソーダ水溶液を徐々に添加し、溶液のｐＨを７．０とし、モノマー調整液とした。モノマー調整液を０℃まで冷却した後、窒素ガスをバブリングして脱気した。脱気終了後、重合開始剤として、Ｎ，Ｎ，Ｎ′、Ｎ′−テトラメチルエチレンジアミンの１０％水溶液１４．７ｍｌ、ペルオキソ２硫酸アンモニウムの１０％水溶液７．４ｍｌを順に加え、重合反応を開始させた。目視にてモノマー調整液の粘度が上昇してきたことを確認し、攪拌並びに窒素ガスバブリングを停止し、密栓状態にて、室温下１６時間重合反応を行った。重合終了後、反応容器よりポリマーを取り出し、約５ｍｍ角に裁断し、４０℃にて真空乾燥、粉砕、分級の後、粒子径１ｍｍ以下の感温性ポリマーＡ２６０．４ｇを得た。
得られたポリマーＡの１％水溶液の粘度を３０℃にて、Ｂ型粘度計を用いて測定したところ、１６００ｍＰａ・ｓであった。また、ポリマー１％、防炎剤として燐酸第２アンモニウム１％を含む水溶液の場合、３０℃下、Ｂ型粘度計を用いて測定したところ、１４０ｍＰａ・ｓであった。感温点５５℃〜６０℃
【００１７】
製造例２：感温性ポリマーＢの製造
２Ｌ容量のガラス製セパラブルフラスコに脱塩水１３６０ｇ、Ｎ−イソプロピルアクリルアミド２０８．５ｇ、アクリル酸８０％水溶液２６．６ｇを入れ、攪拌下モノマーを溶解した。攪拌下、モノマーを溶解した溶液を１５〜２０℃に保ちながら、４８％苛性ソーダ水溶液を徐々に添加し、溶液のｐＨを７．０とし、モノマー調整液とした。モノマー調整液を０℃まで冷却の後、窒素ガスをバブリングし脱気した。脱気終了後、重合開始剤として、Ｎ，Ｎ，Ｎ′、Ｎ′−テトラメチルエチレンジアミンの１０％水溶液１４．７ｍｌ、ペルオキソ２硫酸アンモニウムの１０％水溶液７．４ｍｌを順に加え、重合反応を開始させた。目視にてモノマー調整液の粘度が上昇してきたことを確認し、攪拌並びに窒素ガスバブリングを停止し、密栓状態にて、室温下１６時間重合反応を行った。重合終了後、反応容器よりポリマーを取り出し、約５ｍｍ角に裁断し、４０℃にて真空乾燥、粉砕、分級の後、粒子径１ｍｍ以下の感温性ポリマーＢ２３０ｇを得た。
得られたポリマーＢの１％水溶液の粘度を３０℃下、Ｂ型粘度計を用いて測定したところ、１６００ｍＰａ・ｓであった。また、ポリマー１％、防炎剤として燐酸第２アンモニウム１％を含む水溶液の場合、３０℃下、Ｂ型粘度計を用いて測定した該水溶液の粘度は、２００ｍＰａ・ｓであった。感温点５５℃〜６０℃。
【００１８】
製造例３：感温性ポリマーＣの製造
感温性ポリマーＣは、アクリル酸８０％水溶液を２９．３ｇとした以外は、製造例２と同様の操作を行い製造した。
得られたポリマーＣの１％水溶液の粘度を３０℃下、Ｂ型粘度計を用いて測定したところ、２０００ｍＰａ・ｓであった。また、ポリマー１％、防炎剤として燐酸第２アンモニウム１％を含む水溶液の場合、３０℃下、Ｂ型粘度計を用いて測定した該水溶液の粘度は、２００ｍＰａ・ｓであった。感温点６０℃〜７０℃
。
【００１９】
製造例４：感温性ポリマーＤの製造
重合開始剤を投入前のモノマー調整液温度を２０℃とした以外は、製造例２と同様の操作を行い感温性ポリマーＤ２２９ｇを得た。
得られたポリマーＤの１％水溶液の粘度を３０℃下、Ｂ型粘度計を用いて測定したところ、６００ｍＰａ・ｓであった。また、ポリマー１％、防炎剤として燐酸第２アンモニウム１％を含む水溶液の場合、３０℃下、Ｂ型粘度計を用いて測定した該水溶液の粘度は、１５０ｍＰａ・ｓであった。感温点６０〜７０℃。
【００２０】
試験例１
防災剤として燐酸第２アンモニウム０．５％を含む水９９ｇに感温性ポリマーＢ１ｇを混合溶解した。得られたポリマー水溶液２０ｍｌを、内径１８ｍｍ、長さ１８０ｍｍのガラス製ねじ口試験管に入れ、密栓の後、任意の温度に溶液を加温し、溶液の流動性の有無を目視にて確認した。結果を表１に示す。
表中：
○：溶液全体が固形状態（ハイドロゲルを形成した状態）で試験管を傾けても液が全く流動しない。
△：かなり溶液が増粘状態であるが、まだ流動性が認められる状態。
×：流動性のある液体状態を示す。
【００２１】
表１：温度感応性試験結果

【００２２】
なお、感温性ポリマーＢを使用せずに、燐酸第２アンモニウムのみを溶解させた燐酸第２アンモニウム０．５％水溶液の粘度をＢ型粘度計にて上記の各温度条件下で測定した結果、７５℃以下の温度において溶液は、１０ｍＰａ・ｓ以下の粘度を有する液体状態であった。
【００２３】
試験例２
１）感温性ポリマー水溶液の組成
表２に本試験に供した感温性ポリマー水溶液の組成を示す。水としてイオン交換水を使用し、これに各成分（重量％）を加えて１００とした。
表中、ＤＯＳＳ・Ｎａはジオクチルスルホコハク酸ナトリウムを示す。
【００２４】
表２

【００２５】
２）各溶液の粘度の測定
表２に示した溶液１及び２、並びに溶液３に燐酸水素二アンモニウムを１％加えたもの（溶液３Ａ）、燐酸水素アンモニウム１％とジオクチルスルホコハク酸ナトリウム０．１％を加えた水溶液（溶液３Ｂ）の各粘度を表３に示す。
【００２６】
表３

【００２７】
３）各溶液の感温性試験
試験方法：
▲１▼ 直径１３ｃｍの金属製平皿を２５０℃に均一に加熱した上に試験すべき溶液（試料）を１０ｇ、２０ｇ、５０ｇを滴下して、状態変化を観測する。
▲２▼ 感温点付近で恒温槽中で試料が均一温度になるまで加温しゲル化又は完全に固形化した状況を観測する。
▲３▼ 試料の加熱・冷却を繰り返すことによりその状態を観察する。
【００２８】
結果１：
試験方法▲１▼及び▲２▼の結果を表４に示す。加熱平皿に溶液（試料）を滴下してから水分が蒸発するまでの時間（試験方法▲１▼）と金属製平皿に入れた試料を加温して固形化するか否かを測定した（試験方法▲２▼）。
【００２９】
表４：２５０℃の加熱平皿に滴下して蒸発するまでの時間及び状況

注：○は完全固化する。△は固化するがぶよぶよする。×は固化しない。
なお、平皿滴下時、水は飛散するがその他の溶液は飛散しない。
【００３０】
上記表の結果から分かるように、感温性ポリマー２％水溶液に対して４倍程度の水を加えた溶液も加温によって固形化する。そのため、感温性ポリマー量の２５０倍程度の水を保水することができる。
【００３１】
結果２：
試験方法▲３▼の試料として、上記溶液３Ａ（溶液３に燐酸二水素アンモニウム１％を加えたもの）に水を等量加えた溶液（溶液３Ａ：水＝１：１）を用い、２５０℃に加熱して固形化した試料を常温放置して、温度低下による変化を観察した。その結果を表５に示す。
【００３２】
表５

【００３３】
表５の結果からわかるように、本発明の消火用水は一旦固形化した後は常温付近まで冷却しても燃焼物面に残留し、流出することがない。
【００３４】
試験例３
本発明の消火剤、消火用水と従来より使用されている防火薬剤及び他の混入物との併用について検討した。
感温性ポリマーとして製造例３の感温性ポリマーＣを用い、表６に示す割合の水溶液として各温度での固形化状態を観察した。結果を表６に示す。
【００３５】
表６

注：◎は完全な固形、○は固形（◎より劣る）、＊固形化するが分離等あり、△は柔らかい（固形と言えない）、×は全くの液体。
【００３６】
表６の結果からわかるように、他の防火薬剤（燐安）及び無機物（炭酸ナトリウム）が溶解していても本発明の消火用水は固形化する。このことは、河川の水に対しても適用できることを示している。
【００３７】
試験例４
消火剤として、製造例１で合成した感温性ポリマー１００ｇを用い、燐酸第２アンモニウム５０ｇ、ジオクチルスルホコハク酸ナトリウム５ｇとともに水道水４８４５ｇに溶解し消火用水とした。作製した消火用水３Ｌを水消火器に入れ、圧搾空気を用いて消火器内の圧力を５×１０⁵ Ｐａに加圧し、３ｃｍ角、長さ５０ｃｍの松材５本を１段とし、２０段を格子状に積み上げた櫓に着火し、櫓全体が、独立燃焼状態となった後、消火器より消火用水を放水し、消火試験を行った。同一条件での消火試験を１０回行い、放水開始から鎮火までに要した平均時間（秒）と使用した消火用水の平均使用量（ｋｇ）の積算値を使用した消火用水の消火効率とし、その値を算出したところ、９６．７ｋｇ・秒であった。更に、消火作業中並びに鎮火直後、放水した消火用水の飛散・流出は認められなかった。
【００３８】
試験例５
消火用水として、製造例１で合成した感温性ポリマー５０ｇ、燐酸第２アンモニウム５０ｇ、ジオクチルスルホコハク酸ナトリウム５ｇを水道水４８４５ｇに溶解したものを用いた以外は、試験例４と同様の操作にて消火試験を行った。その結果、消火効率は１００．０ｋｇ・秒であった。更に、消火作業中並びに鎮火直後において、放水した消火用水の飛散・流失は認められなかった。
【００３９】
比較試験例１
消火用水として、燐酸第２アンモニウム５０ｇ、ジオクチルスルホコハク酸ナトリウム５ｇを水道水４９４５ｇに溶解したものを用いた以外は、試験例４と同様の操作にて消火試験を行った。その結果、消火効率は１３２．２ｋｇ・秒であった。更に、消火作業中並びに鎮火直後において、放水した消火用水の飛散・流失が認められた。
【００４０】
比較試験例２
水道水を消火用水として用いた以外は、試験例４と同様の操作にて消火試験を行った。その結果、消火効率は２５５．２ｋｇ・秒であった。更に、消火作業中並びに鎮火直後において、放水した消火用水の飛散・流出が認められた。
【００４１】
試験例６
直径２５０ｍｍ、深さ７０ｍｍの中華鍋に５００ｍｌの大豆油を入れガスコンロにて加熱発火させた。発火３０秒後に、消火液（消火用水）として、製造例２で合成した感温性ポリマーＢの１％水溶液３００ｍｌを柄付きのステンレス製ジョッキを用い中華鍋に一括投入し、投入から鎮火に至る時間を測定すると共に、炎の様子を目視にて確認した。その結果、鎮火迄に要した時間は３秒であり、消火液投入時から鎮火に至るまで炎が高く上がる現象は観察されなかった。更に、鎮火後、消火剤がハイドロゲルの膜状となり鍋上部を覆っていることが確認でき、再発火もなかった。
【００４２】
試験例７
感温性ポリマーＢ１％、燐酸アンモニ第２アンモニウム１％、ジオクチルスルホコハク酸ナトリウム０．１％の水溶液を消火液として用いた以外は、試験例６と同様の評価を行った。その結果、鎮火迄に要した時間は７秒であり、消火液投入時から鎮火に至るまで、炎が高く上がる現象はほとんど観察されなかった。更に、鎮火後、ハイドロゲルの固まりとなった消火剤が、油中に存在することが確認でき、再発火もなかった。
【００４３】
試験例８
製造例４で合成した感温性ポリマーＤ１％の水溶液を消火液として用いた以外は、試験例６と同様の評価を行った。その結果、鎮火迄に要した時間は２秒であり、消火液投入時から鎮火に至るまで、炎が高く上がる現象はほとんど観察されなかった。更に、鎮火後、消火剤がハイドロゲルの膜状となり鍋上部を覆っていることが確認でき、再発火もなかった。
【００４４】
比較試験例３
酢酸カリウム２５％、四ホウ酸カリウム５％の割合で溶解した水溶液を消火液として用いた以外は、試験例６と同様の評価を行った。その結果、鎮火迄に要した時間は９秒であったが、消火液投入直後に炎が高く上がり、周辺に油が飛散した。鎮火後、再発火については認められなかった。
【００４５】
試験例９
消火剤として、製造例４で合成した感温性ポリマーＤ１００ｇを用い、その１％水溶液３ｋｇを直径２ｍｍφのノズルのついた消火器（ハッタ製：消火訓練用消火器、テスター７）に入れ、窒素ガスを用いて消火器内の圧力を５×１０⁵ Ｐａに加圧し、３ｃｍ角、長さ５０ｃｍの松材５本を１段とし、２０段を格子状に積み上げた櫓に着火し、櫓全体が、独立燃焼状態となった後、消火器より消火用水を放水し、消火試験を行った。同一条件での消火試験を１０回行い、放水開始から鎮火までに要した平均時間（秒）と使用した消火用水の平均使用量（ｋｇ）の積算値を使用した消火用水の消火効率とし、その値を算出したところ、９７．６ｋｇ・秒であった。更に、消火作業中並びに鎮火直後、放水した消火用水の飛散・流出は認められず、消火後、櫓を１時間放置したが再燃も認められなかった。
【００４６】
試験例１０
消火用水として、製造例４で合成した感温性ポリマー５０ｇ、燐酸第２アンモニウム５０ｇ、ジオクチルスルホコハク酸ナトリウム５ｇを水道水４８４５ｇに溶解したものを用いた以外は、試験例９と同様の操作にて消火試験を行った。その結果、消火効率は５８．３ｋｇ・秒であった。更に、消火作業中並びに鎮火直後において、放水した消火用水の飛散・流出は認められなかった。
【００４７】
比較試験例４
消火用水として水道水を使用した以外は試験例９と同様の操作にて消火試験を行った。その結果、消火効率は２４２．３ｋｇ・秒であった。更に、消火終了の後、約２０分で再び当初の燃焼状態に近い状態まで再燃した。
【００４８】
【発明の効果】
本発明の感温性ポリマーを含む水を消火用水として使用するためには、
▲１▼ 消防に使用する水であるから常温ないし常温より若干高めの温度は液体のままであること、
▲２▼ 火災時の燃焼熱のみで瞬時に水が固まること、
▲３▼ 火災熱に曝されても容易に分解しないこと、
▲４▼ 鎮火後可燃物が冷却して常温になった時にも流動しないこと、
等のことが必要であるが、上記各試験例によって本発明の消火剤、これを水に溶解した消火用水はこれらの条件を満足し、充分に消火・延焼防止能力を有することが認められた。
【００４９】
調整原液としての感温性ポリマー２％を含む溶液は、水に比べ６０〜３００倍の粘度を有するが６０℃位までは液体で安定しており、濃厚液として火災現場で固形化することなく消火用の水に供給できる。また、これらの感熱性ポリマーは消火能力のある燐酸第２アンモニウム等を添加することにより感温点を明瞭化することができる。この他、河川の水を使用しても同様に固形化することができるので、都市部の火災のみならず、山林火災等にも使用することができる。
更に、感温性ポリマーとしてＮ−イソプロピルアクリルアミドを主成分とするポリマー、特にＮ−イソプロピルアクリルアミド７５〜９９モル％とアクリル酸ナトリウム１〜２５モル％を共重合してなるポリマーを消火剤として用いることにより、天ぷら油火災に対しても、より安全にかつ効率的に使用することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fire extinguishing agent that can hold fire-extinguishing water on the surface of an object to be extinguished, fire-extinguishing water, and a fire-extinguishing method using the same.
[0002]
[Prior art]
Conventionally, "water" has been mainly used for fire extinguishing. In Japan, water resources are relatively abundant and water supply is widespread, so water supply is mainly used for fire extinguishing, and fire prevention water tanks and river water are used supplementarily. However, if the water pipe ruptures or the water tank is damaged due to a major earthquake such as the Great Hanshin-Awaji Earthquake, it must be extinguished with limited water. The same applies to a fire in a forest. As a fire extinguishing method in these cases, for example, methods such as using chemicals for fire extinguishing or applying sand are adopted, but the former is a problem that it is more expensive than water or requires attention to use The latter has problems such as being unable to be easily sent to a fire extinguishing point because it is heavy and has no fluidity.
[0003]
The water applied to the combustion product extinguishes by the action of cooling the combustion product to the ignition point or lower than the ignition point or the blocking action of oxygen by the latent heat of vaporization, but most of the water used flows down from the surface of the combustion product Therefore, the result is inefficient. If the water used for extinguishing remains on the surface of the combustion product, it is considered that the above-described extinguishing action can be obtained more sufficiently.
As one of countermeasures, the use of superabsorbent polymers has been studied. This polymer solidifies several hundred to several thousand times its own amount of water in a few seconds when it comes into contact with water. However, solidification is significantly inhibited by substances dissolved in water, and it is decomposed and solidified by ultraviolet rays. There is a disadvantage that the drained water is easily washed away. In addition, the polymer has a problem that it must be handled separately from fire extinguishing water. In addition, there are reports of drugs in which a thermal gelling agent such as a cellulose derivative and a superabsorbent resin are added (for example, JP-A-1-56070, etc.). There was a problem that removal was not easy.
[0004]
On the other hand, tempura oil fires as a cause of fires in general households tend to increase in recent years. Considering housing conditions in urban areas, fires in general households can also cause serious disasters, so there is a need for a reliable and safer fire extinguishing method at the initial stage of the fire.
Conventionally, there are powder-based fire extinguishing agents, gas-based fire-extinguishing agents, and water-based fire-extinguishing agents as widely used extinguishing agents. However, in the case of tempura oil fires, re-ignition if not cooled below the ignition point of the oil. It is believed that water-based fire extinguishing agents are preferred. However, conventional water-based fire extinguishing agents have problems such as bumping, fire extinguishing liquid showing high alkalinity, and high flame.
[0005]
[Problems to be solved by the invention]
In view of these points, the present invention is intended to provide a fire extinguishing agent and water for fire extinguishing that can be handled in the same manner as conventional fire extinguishing water and in which the jetted fire extinguishing water remains on the surface of the combustion product.
Furthermore, the present invention is intended to provide a fire extinguishing agent and water for fire fighting that have an excellent fire fighting action against oil fires such as tempura oil fires.
[0006]
[Means for Solving the Problems]
The present inventors have added water to fire extinguishing “water”, the water remains liquid at room temperature, has a relatively small viscosity and fluidity, and can be used satisfactorily with existing firefighting pumps, etc. It contains a large amount of water on the surface, solidifies, blocks air and has a cooling effect. Furthermore, as a result of various researches for substances having an excellent fire extinguishing action against oil fires, it was found that a temperature-sensitive polymer can achieve the purpose, and the present invention was completed.
[0007]
That is, the present invention includes (1) a fire-extinguishing agent characterized by comprising a temperature-sensitive polymer that is water-soluble at a specific set temperature or lower and solidifies with water at a set temperature or higher,
(2) The extinguishing agent according to (1) above, wherein the solidification of the temperature-sensitive polymer is a hydrogel,
(3) The fire-extinguishing agent according to the above (1) and (2), wherein the temperature-sensitive polymer is a water-soluble acrylamide polymer,
(4) The fire-extinguishing agent according to any one of (1) to (3), wherein the temperature-sensitive polymer is a polymer mainly composed of N-isopropylacrylamide.
(5) The above-mentioned (1) to (4), wherein the thermosensitive polymer is a polymer obtained by copolymerizing N-isopropylacrylamide 75 to 99 mol% and sodium acrylate 1 to 25 mol%. Fire extinguishing agent,
(6) Fire extinguishing water characterized by dissolving the fire extinguishing agent according to (1) to (5) in water,
(7) In addition to a temperature-sensitive polymer, a fire-extinguishing agent, a flameproofing agent, and a penetrating agent for these agents as required,
(8) The water for fire extinguishing according to (6) and (7) above, wherein the viscosity of the aqueous solution is 20 to 2000 mPa · s (30 ° C.),
(9) A fire extinguishing method using the water for fire extinguishing according to claims (6) to (8),
(10) The fire extinguishing method according to the above (9), characterized by jetting while adding a temperature sensitive polymer aqueous solution in which a temperature sensitive polymer is dissolved in advance to a predetermined concentration to water for fire extinguishing,
Is to provide.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The temperature-sensitive polymer used in the present invention is “temperature-sensitive, which is water-soluble below a specific set temperature (hereinafter referred to as temperature-sensitive point) and solidifies (becomes a water-insoluble hydrogel) above the temperature-sensitive point. It is defined as “adhesive polymer”.
In the present invention, this temperature-sensitive polymer is added to water for fire fighting as a fire extinguisher, and the aqueous solution has fluidity at room temperature and can be used for fire fighting with fire fighting equipment such as conventional fire pumps as well as fire fighting water. , When sprayed or sprayed on a fire (combustion), it is gelled or solidified in a state containing water with the heat of combustion and remains on the surface of the combustion, preventing fire extinguishing, spreading fire and reignition It is.
[0009]
The temperature sensitive polymer of the present invention is, for example,
(1) a method of copolymerizing a vinyl monomer (a) whose homopolymer has a lower critical solution temperature in water and another vinyl monomer (b) copolymerizable with (a), and (2) methylcellulose It can be obtained by a method such as graft polymerization of a vinyl monomer having an ionic group such as sodium acrylate to a polymer having a lower critical solution temperature in water such as hydroxypropylcellulose. Among the above production methods, the method (1) is more preferable because the temperature sensitive point of the obtained polymer can be easily adjusted.
As the vinyl monomer (a), N-substituted acrylamide such as N-isopropyl (meth) acrylamide, Nn-propyl (meth) acrylamide, N, N-diethylacrylamide, acryloylpiperidine, acryloylpyrrolidine, vinylcaprolactam and derivatives thereof , Alkyl vinyl ethers such as methyl vinyl ether and ethyl vinyl ether, and N-vinyl alkyl amides such as N-vinyl isobutyramide.
[0010]
Examples of the vinyl monomer (b) include acrylic acid and salts thereof (sodium salt, potassium salt, calcium salt, etc.), 2-acrylamido-2-propanesulfonic acid and salts thereof (sodium salt, potassium salt, calcium salt, etc.), N , N-dimethylaminopropylacrylamide and salts thereof (sulfate, monomethyl sulfate, dimethyl sulfate, methyl chloride, etc.), N, N-dimethylaminoethyl (meth) acrylate and salts thereof (sulfate, monomethyl sulfate, Vinyl monomers having ionic groups such as dimethyl sulfate and methyl chloride), acrylamide derivatives such as acrylamide, diacetone acrylamide and tert-butyl acrylamide, methyl (meth) acrylate, ethyl (meth) acrylate, (meth ) Butyl acrylate, hydroxyethyl (meth) (Meth) acrylic acid esters such as acrylate and the like.
[0011]
The solidification temperature of the temperature-sensitive polymer is not particularly limited, but it is necessary that the temperature-sensitive polymer be not less than a temperature at which it does not gel at room temperature, a temperature at a fire site, or a temperature in midsummer. In consideration of the temperature in winter and the fire site, the temperature is set to 10 to 140 ° C. (100 ° C. or higher is a value measured under pressure), preferably 50 to 100 ° C.
As a specific temperature-sensitive polymer, a polymer having N-isopropylacrylamide as a main component as a vinyl monomer (a) and copolymerized with another vinyl monomer (b) is preferable, and particularly 75-99 mol of N-isopropylacrylamide. % And a vinyl monomer (b) copolymerized with 1 to 25 mol% of sodium acrylate are more preferable because they have excellent fire extinguishing performance in tempura oil fires and petroleum stove fires.
[0012]
The present invention further provides fire-fighting water in which a fire-extinguishing agent containing a temperature-sensitive polymer is dissolved in water.
Regarding the molecular weight of the temperature-sensitive polymer and the concentration in water, 20 to 2000 mPa · s of water containing the temperature-sensitive polymer is in the temperature range where the temperature-sensitive polymer is water-soluble in the state of an aqueous solution used for fire fighting. An amount having a viscosity of (30 ° C.) is desirable. If the viscosity is lower than this range, the fire-extinguishing water cannot be made sufficiently hydrogel-like and high fire extinguishing and fire spread prevention effects cannot be expected. On the other hand, when the viscosity is higher than this range, the transportation / water discharge operation becomes difficult, which is not preferable.
Although it varies depending on the type and molecular weight of the temperature-sensitive polymer, the aqueous solution is about 0.1 to 10% by weight, preferably about 0.5 to 2% by weight with respect to water. If the concentration is less than 0.1% by weight, solidification by heat is not sufficient, and if it exceeds 10% by weight, the viscosity of the aqueous solution becomes high and the fluidity may be poor.
[0013]
A chemical that has been conventionally used as a fire-extinguishing agent can be added to the fire-extinguishing water containing the temperature-sensitive polymer, if necessary. For example, a fire extinguishing agent such as primary ammonium phosphate and secondary ammonium phosphate, a flame retardant, and a surfactant as a penetrating agent such as sodium dioctyl sulfosuccinate may be mixed and dissolved. The solidification action of the temperature-sensitive polymer can prevent the flameproofing agent from scattering and flowing out, so that fire extinguishing and fire spread prevention can be performed more effectively.
These fire extinguishing agents, flameproofing agents, penetrants and the like are desirably used at a concentration of 0.05 to 5% by weight with respect to water for fire extinguishing. When the concentration is 0.05% by weight or less, the effect of the flameproofing agent or penetrant is poor, and the addition of 5% by weight or more is not preferable because it causes precipitation of a temperature-sensitive polymer.
[0014]
The water for fire extinguishing of the present invention can be used for fire extinguishing by discharging water as it is by a method similar to a general fire extinguishing method. For example, it may be sprayed from the hose in the form of spray or water droplets, solidified in the flame and dropped / attached to the surface of the combustion product, or it may be injected by a conventional fire hose and solidified on the surface of the combustion product You may make it do.
In addition, a concentrated aqueous solution of a temperature-sensitive polymer may be prepared in advance, and the water may be discharged while being added to the water for fire extinguishing at the time of fire extinguishing.
[0015]
[Examples and test examples]
Although the manufacture example of a thermosensitive polymer and the test example of a fire extinguisher and fire extinguishing water are shown below, this invention is not limited to these examples. In the following examples, “%” means “% by weight” unless otherwise specified.
[0016]
Production Example 1: Production of thermosensitive polymer A 1360 g of demineralized water was placed in a 2 L glass separable flask, and 222.6 g of N-isopropylacrylamide was added and dissolved under stirring. After the dissolved solution was cooled to 10 ° C., 35.5 g of 2-acrylamido-2-methylpropanesulfonic acid was added and dissolved with stirring. While maintaining the temperature of this solution at 15 ° C. or lower, a 48% aqueous sodium hydroxide solution was gradually added to adjust the pH of the solution to 7.0, thereby preparing a monomer adjusting solution. The monomer adjustment liquid was cooled to 0 ° C., and then degassed by bubbling nitrogen gas. After degassing, as polymerization initiators, 14.7 ml of a 10% aqueous solution of N, N, N ′, N′-tetramethylethylenediamine and 7.4 ml of a 10% aqueous solution of ammonium peroxodisulfate were sequentially added to initiate the polymerization reaction. It was. After confirming that the viscosity of the monomer adjustment liquid had been increased by visual observation, stirring and nitrogen gas bubbling were stopped, and a polymerization reaction was carried out at room temperature for 16 hours in a sealed state. After the completion of the polymerization, the polymer was taken out from the reaction vessel, cut into about 5 mm square, vacuum dried at 40 ° C., pulverized and classified to obtain 260.4 g of a temperature sensitive polymer A having a particle diameter of 1 mm or less.
It was 1600 mPa * s when the viscosity of the 1% aqueous solution of the obtained polymer A was measured at 30 degreeC using the B-type viscosity meter. In the case of an aqueous solution containing 1% polymer and 1% diammonium phosphate as a flameproofing agent, it was 140 mPa · s when measured using a B-type viscometer at 30 ° C. Temperature sensitive point 55 ℃ -60 ℃
[0017]
Production Example 2: Production of thermosensitive polymer B In a 2 L glass separable flask, 1360 g of demineralized water, 208.5 g of N-isopropylacrylamide, and 26.6 g of an 80% aqueous solution of acrylic acid were added, and the monomer was dissolved under stirring. While stirring, the solution in which the monomer was dissolved was maintained at 15 to 20 ° C., and a 48% aqueous sodium hydroxide solution was gradually added to adjust the pH of the solution to 7.0 to prepare a monomer adjusting solution. After the monomer adjustment liquid was cooled to 0 ° C., nitrogen gas was bubbled and degassed. After degassing, as polymerization initiators, 14.7 ml of a 10% aqueous solution of N, N, N ′, N′-tetramethylethylenediamine and 7.4 ml of a 10% aqueous solution of ammonium peroxodisulfate were sequentially added to initiate the polymerization reaction. It was. After confirming that the viscosity of the monomer adjustment liquid had been increased by visual observation, stirring and nitrogen gas bubbling were stopped, and a polymerization reaction was carried out at room temperature for 16 hours in a sealed state. After the completion of the polymerization, the polymer was taken out from the reaction vessel, cut into about 5 mm square, vacuum dried at 40 ° C., pulverized, and classified to obtain 230 g of thermosensitive polymer B having a particle diameter of 1 mm or less.
The viscosity of the obtained 1% aqueous solution of polymer B was measured at 30 ° C. using a B-type viscometer and found to be 1600 mPa · s. In the case of an aqueous solution containing 1% polymer and 1% diammonium phosphate as a flameproofing agent, the viscosity of the aqueous solution measured using a B-type viscometer at 30 ° C. was 200 mPa · s. Temperature point 55 ° C-60 ° C.
[0018]
Production Example 3: Production of Temperature Sensitive Polymer C Thermosensitive polymer C was produced by the same operation as in Production Example 2 except that 29.3 g of an 80% aqueous solution of acrylic acid was used.
It was 2000 mPa * s when the viscosity of the obtained 1% aqueous solution of the polymer C was measured using the B-type viscometer under 30 degreeC. In the case of an aqueous solution containing 1% polymer and 1% diammonium phosphate as a flameproofing agent, the viscosity of the aqueous solution measured using a B-type viscometer at 30 ° C. was 200 mPa · s. Temperature sensitive point 60 ℃ ~ 70 ℃
.
[0019]
Production Example 4: Production of thermosensitive polymer D A thermosensitive polymer D229g was obtained in the same manner as in Production Example 2 except that the temperature of the monomer adjusting solution before addition of the polymerization initiator was 20 ° C.
The viscosity of a 1% aqueous solution of the obtained polymer D was measured at 30 ° C. using a B-type viscometer, and was 600 mPa · s. In the case of an aqueous solution containing 1% polymer and 1% diammonium phosphate as a flameproofing agent, the viscosity of the aqueous solution measured with a B-type viscometer at 30 ° C. was 150 mPa · s. Temperature sensitive point 60-70 ° C.
[0020]
Test example 1
As a disaster prevention agent, 1 g of thermosensitive polymer B was mixed and dissolved in 99 g of water containing 0.5% of dibasic ammonium phosphate. 20 ml of the obtained polymer aqueous solution was put into a glass screw-cap test tube having an inner diameter of 18 mm and a length of 180 mm, and after sealing, the solution was heated to an arbitrary temperature, and the presence or absence of fluidity of the solution was visually confirmed. . The results are shown in Table 1.
In the table:
○: The liquid does not flow at all even if the test tube is tilted when the whole solution is in a solid state (a state in which a hydrogel is formed).
Δ: The solution is considerably thickened but still fluid.
X: Indicates a fluid liquid state.
[0021]
Table 1: Temperature sensitivity test results

[0022]
In addition, the result of having measured the viscosity of the 0.5% aqueous solution of secondary ammonium phosphate in which only secondary ammonium phosphate was dissolved without using the temperature sensitive polymer B with a B-type viscometer under the above temperature conditions. At a temperature of 75 ° C. or lower, the solution was in a liquid state having a viscosity of 10 mPa · s or lower.
[0023]
Test example 2
1) Composition of temperature-sensitive polymer aqueous solution Table 2 shows the composition of the temperature-sensitive polymer aqueous solution used in this test. Ion exchange water was used as water, and each component (% by weight) was added thereto to make 100.
In the table, DOSS · Na represents sodium dioctylsulfosuccinate.
[0024]
Table 2

[0025]
2) Measurement of viscosity of each solution Solution 1 and 2 shown in Table 2, and solution 3 with 1% diammonium hydrogen phosphate added (solution 3A), 1% ammonium hydrogen phosphate and sodium dioctylsulfosuccinate 0.1 Table 3 shows the respective viscosities of the aqueous solution (solution 3B) with% added.
[0026]
Table 3

[0027]
3) Temperature sensitivity test test method for each solution:
{Circle around (1)} 10 g, 20 g, and 50 g of a solution (sample) to be tested are dropped on a metal flat dish having a diameter of 13 cm uniformly heated to 250 ° C., and the state change is observed.
{Circle around (2)} Observe the state of gelation or solidification by heating the sample until it reaches a uniform temperature in a thermostatic chamber near the temperature sensing point.
(3) Observe the state by repeatedly heating and cooling the sample.
[0028]
Result 1:
Table 4 shows the results of the test methods (1) and (2). The time from when the solution (sample) was dropped to the heated flat dish until the water evaporated (test method (1)) and whether the sample placed in the metal flat dish was heated and solidified was measured (test Method (2)).
[0029]
Table 4: Time and conditions for dropping and evaporating on a heated flat plate at 250 ° C

Note: ○ solidifies completely. △ solidifies but smolders. X does not solidify.
In addition, when a flat dish is dropped, water is scattered but other solutions are not scattered.
[0030]
As can be seen from the results in the above table, a solution obtained by adding about 4 times the water to the 2% aqueous solution of the thermosensitive polymer is also solidified by heating. Therefore, water about 250 times the amount of the temperature sensitive polymer can be retained.
[0031]
Result 2:
As a sample of test method (3), a solution (solution 3A: water = 1: 1) in which an equal amount of water was added to the above solution 3A (a solution 3 added with 1% ammonium dihydrogen phosphate) was used at 250 ° C. The sample solidified by heating to room temperature was allowed to stand at room temperature, and changes due to temperature decrease were observed. The results are shown in Table 5.
[0032]
Table 5

[0033]
As can be seen from the results in Table 5, the water for fire extinguishing of the present invention once solidifies, remains on the combustion product surface and does not flow out even when cooled to near room temperature.
[0034]
Test example 3
The combined use of the fire-extinguishing agent of the present invention, fire-fighting water, and conventionally used fire-preventing agents and other contaminants was studied.
The temperature-sensitive polymer C of Production Example 3 was used as the temperature-sensitive polymer, and the solidified state at each temperature was observed as an aqueous solution having the ratio shown in Table 6. The results are shown in Table 6.
[0035]
Table 6

Note: ◎ is completely solid, ○ is solid (inferior to ◎), * solidifies but has separation, etc. Δ is soft (not solid), x is a completely liquid.
[0036]
As can be seen from the results in Table 6, the fire-fighting water of the present invention is solidified even if other fireproofing agents (phosphorus) and inorganic substances (sodium carbonate) are dissolved. This indicates that it can also be applied to river water.
[0037]
Test example 4
As a fire extinguisher, 100 g of the temperature-sensitive polymer synthesized in Production Example 1 was used and dissolved in 4845 g of tap water together with 50 g of dibasic ammonium phosphate and 5 g of sodium dioctylsulfosuccinate to obtain fire extinguishing water. The fire extinguishing water 3L thus prepared is put into a water fire extinguisher, the pressure inside the fire extinguisher is increased to 5 × 10 ⁵ Pa using compressed air, and 5 pine trees of 3 cm square and 50 cm in length are made up of 20 steps. After the firewood was ignited in a grid, the firewood was discharged from the fire extinguisher and fire extinguishing test was conducted. The fire extinguishing test under the same conditions was conducted 10 times, and the fire extinguishing efficiency of the fire extinguishing water using the integrated value of the average time (seconds) required from the start of water discharge to extinguishing and the average usage of fire extinguishing water (kg) was used. The value calculated was 96.7 kg · sec. In addition, during fire extinguishing work and immediately after the fire was extinguished, there was no scattering or outflow of fire-fighting water discharged.
[0038]
Test Example 5
The same operation as in Test Example 4 was conducted except that 50 g of the temperature-sensitive polymer synthesized in Production Example 1, 50 g of diammonium phosphate, and 5 g of sodium dioctylsulfosuccinate were dissolved in 4845 g of tap water as fire-extinguishing water. A fire extinguishing test was conducted. As a result, the fire extinguishing efficiency was 100.0 kg · sec. In addition, during fire extinguishing work and immediately after extinguishing, there was no scattering or loss of fire-fighting water discharged.
[0039]
Comparative Test Example 1
A fire extinguishing test was performed in the same manner as in Test Example 4 except that 50 g of dibasic ammonium phosphate and 5 g of sodium dioctyl sulfosuccinate dissolved in 4945 g of tap water were used as fire fighting water. As a result, the fire extinguishing efficiency was 132.2 kg · sec. Furthermore, during fire extinguishing work and immediately after extinguishing the fire, the fire extinguishing water was scattered and washed away.
[0040]
Comparative test example 2
A fire extinguishing test was performed in the same manner as in Test Example 4 except that tap water was used as fire fighting water. As a result, the fire extinguishing efficiency was 255.2 kg · sec. In addition, during fire extinguishing work and immediately after extinguishing the fire, the fire-fighting water was scattered and discharged.
[0041]
Test Example 6
500 ml of soybean oil was put in a wok with a diameter of 250 mm and a depth of 70 mm, and heated and ignited with a gas stove. 30 seconds after ignition, 300 ml of a 1% aqueous solution of temperature-sensitive polymer B synthesized in Production Example 2 as a fire extinguishing liquid (fire-extinguishing water) is charged all at once into a wok using a stainless steel mug with a handle. While measuring time, the state of the flame was confirmed visually. As a result, the time required to extinguish the fire was 3 seconds, and no phenomenon was observed in which the flame was raised from the time when the fire extinguishing liquid was introduced until the fire was extinguished. Furthermore, after the fire was extinguished, it was confirmed that the fire extinguisher became a hydrogel film covering the top of the pan, and there was no recurrence.
[0042]
Test Example 7
Evaluations were made in the same manner as in Test Example 6 except that an aqueous solution of 1% temperature-sensitive polymer B, 1% ammonium ammonium secondary phosphate, and 0.1% sodium dioctylsulfosuccinate was used as the fire extinguishing solution. As a result, the time required to extinguish was 7 seconds, and from the time when the fire extinguishing liquid was added to the extinction, there was hardly any phenomenon that the flame increased. Furthermore, after extinguishing, it was confirmed that the fire extinguisher that became a mass of hydrogel was present in the oil, and there was no recurrence.
[0043]
Test Example 8
The same evaluation as in Test Example 6 was performed, except that an aqueous solution of a thermosensitive polymer D1% synthesized in Production Example 4 was used as a fire extinguishing liquid. As a result, the time required for extinguishing was 2 seconds, and from the time when the fire extinguishing liquid was added to the extinguishing, a phenomenon in which the flame was raised was hardly observed. Furthermore, after the fire was extinguished, it was confirmed that the fire extinguisher became a hydrogel film covering the top of the pan, and there was no recurrence.
[0044]
Comparative test example 3
The same evaluation as in Test Example 6 was performed except that an aqueous solution dissolved in a ratio of 25% potassium acetate and 5% potassium tetraborate was used as a fire extinguishing liquid. As a result, it took 9 seconds to extinguish the fire, but immediately after the fire extinguishing liquid was added, the flame rose and the oil scattered around. There was no recurrence after the fire was extinguished.
[0045]
Test Example 9
As a fire extinguisher, 100 g of the thermosensitive polymer D synthesized in Production Example 4 was used, and 3 kg of the 1% aqueous solution was put into a fire extinguisher with a nozzle having a diameter of 2 mmφ (manufactured by Hatta: fire extinguisher for fire fighting training, tester 7), and nitrogen. Using gas, pressurize the fire extinguisher to 5 × 10 ⁵ Pa, ignite the firewood stacked in a grid with 5 pine pieces of 3 cm square and 50 cm length, and fire the 20 firewood However, after becoming an independent combustion state, water for fire extinguishing was discharged from a fire extinguisher and a fire extinguishing test was conducted. The fire extinguishing test under the same conditions was conducted 10 times, and the fire extinguishing efficiency of the fire extinguishing water using the integrated value of the average time (seconds) required from the start of water discharge to extinguishing and the average usage of fire extinguishing water (kg) was used. The calculated value was 97.6 kg · sec. Furthermore, during fire extinguishing work and immediately after extinguishing the fire, the fire extinguishing water was not scattered or discharged, and after the fire was extinguished, the firewood was left for 1 hour, but no relapse was observed.
[0046]
Test Example 10
The same operation as in Test Example 9 was conducted except that 50 g of the thermosensitive polymer synthesized in Production Example 4, 50 g of diammonium phosphate, and 5 g of sodium dioctylsulfosuccinate were dissolved in 4845 g of tap water as fire-extinguishing water. A fire extinguishing test was conducted. As a result, the fire extinguishing efficiency was 58.3 kg · sec. In addition, during fire extinguishing work and immediately after extinguishing the fire, there was no scattering or outflow of fire-fighting water.
[0047]
Comparative Test Example 4
A fire extinguishing test was performed in the same manner as in Test Example 9 except that tap water was used as fire extinguishing water. As a result, the fire extinguishing efficiency was 242.3 kg · sec. Furthermore, after the extinguishing of fire, it re-flared to a state close to the initial combustion state again in about 20 minutes.
[0048]
【The invention's effect】
In order to use the water containing the thermosensitive polymer of the present invention as water for fire extinguishing,
(1) Since it is water used for fire fighting, it should be liquid at room temperature or slightly higher than room temperature.
(2) Water can be instantly solidified only by the heat of combustion during a fire,
(3) Do not decompose easily even if exposed to fire heat.
▲ 4 ▼ Do not flow when the combustible material cools to room temperature after quenching,
It is recognized that the fire extinguishing agent of the present invention and water for extinguishing fire dissolved in water satisfy these conditions and have sufficient fire extinguishing / fire spread prevention ability according to each of the above test examples. .
[0049]
A solution containing 2% of a temperature-sensitive polymer as an adjustment stock solution has a viscosity 60 to 300 times that of water, but is stable up to about 60 ° C. as a liquid, and does not solidify as a concentrated liquid at the fire site. Can be supplied to fire-fighting water. In addition, these thermosensitive polymers can clarify the temperature sensitive point by adding diammonium phosphate having a fire extinguishing ability. In addition, since it can be solidified in the same way even if river water is used, it can be used not only for urban fires but also for forest fires.
Furthermore, a polymer comprising N-isopropylacrylamide as a main component as a temperature-sensitive polymer, particularly a polymer obtained by copolymerizing N-isopropylacrylamide 75 to 99 mol% and sodium acrylate 1 to 25 mol% is used as a fire extinguishing agent. Therefore, it can be used more safely and efficiently against a tempura oil fire.

Claims

Water-soluble in the following specific set temperature, it solidified contain water above the set temperature, and a fire extinguishing agent which the set temperature comprises a temperature-sensitive polymer is 50 to 100 ° C., the temperature sensitive polymer , A polymer obtained by copolymerizing N-isopropylacrylamide and another vinyl monomer, and the other vinyl monomer is acrylic acid and its salt, 2-acrylamido-2-methylpropanesulfonic acid and its salt, N, N- A fire extinguishing agent, which is at least one of dimethylaminopropylacrylamide and its salt, N, N-dimethylaminoethyl (meth) acrylate and its salt .

The fire-extinguishing agent according to claim 1, wherein the temperature-sensitive polymer is a polymer obtained by copolymerizing 75 to 99 mol% of N-isopropylacrylamide and 1 to 25 mol% of sodium acrylate.

A fire-extinguishing water, wherein the fire-extinguishing agent according to claim 1 or 2 is dissolved in water.

The water for fire extinguishing according to claim 3 , further comprising a fire extinguishing agent other than the fire extinguishing agent containing the temperature sensitive polymer, or a flameproofing agent in addition to the temperature sensitive polymer.

The water for fire extinguishing according to claim 3 or 4, wherein the viscosity of the aqueous solution is 20 to 2000 mPa · s (30 ° C).

A fire extinguishing method using the fire extinguishing water according to any one of claims 3 to 5 .