JP2005027742A

JP2005027742A - Water based fire extinguishant, and fire extinguishing method using the same

Info

Publication number: JP2005027742A
Application number: JP2003193644A
Authority: JP
Inventors: Iwamine Ou; 岩峰王; Koji Teramoto; 広司寺本; Takashi Maruyama; 学士丸山
Original assignee: Kohjin Holdings Co Ltd; Kohjin Co
Current assignee: Kohjin Holdings Co Ltd; Kohjin Co
Priority date: 2003-07-08
Filing date: 2003-07-08
Publication date: 2005-02-03

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water based fire extinguishant having an excellent initial fire extinguishing power even by a small using amount against a normal fire, an oil fire, a forest fire, a bush fire or the like and also having an excellent rekindled fire preventing effect without causing any physical property change in the agent even when preserved for a long period of time, and to provide a fire extinguishing method using the fire extinguishant. <P>SOLUTION: A temperature sensitive polymer, which has no lower limit critical solution temperature up to 100°C in pure water and has the lower limit critical solution temperature of 35 to 100°C in the water solution mixture of 5 wt.% ammonium dihydrogen phosphate and 5 wt.% diammonium hydrogen phosphate, and an extinguishing agent such as phosphate, condensed phosphate, sulphate, bicarbonate or tungstate are dissolved into water , thereby preparing the water based fire extinguishant. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、感温性ポリマーと消炎剤とを併用する、少量の水で効率の良い消火活動を行うことができ、しかも水損を著しく減少させ、速消火性能、再着火防止性能に優れた水系消火薬剤、及びそれを用いた消火方法に関する。
【０００２】
【従来の技術】
一般的な消火手段としては火元に向けて淡水を放射散布する方法がある。これは、水の蒸発により大量の熱（蒸発潜熱）を奪い、燃焼物を着火温度以下の温度に冷却させるだけでなく、燃焼物から蒸発潜熱を奪い蒸発することにより、体積が約１７００倍にも増加し、発生した水蒸気による燃焼物への空気の遮断いわゆる窒息効果も生じ、消火が容易になるためである。しかしながら、燃焼物に掛けられた水の大部分は、流れ落ちてしまい、消火効率が極めて低いため、連続放水は必要となるほか、消火にも時間がかかる。
【０００３】
淡水の消火性能を向上させるために、数多くの研究がなされており、主として消炎効果を有する無機塩、有機塩、燐酸と有機アミンの中和塩、各種の界面活性剤などを高濃度添加してなるものである（特許文献１）。しかしながら、これらの水系消火薬剤は、初期消火性能を向上させたものの、燃焼物の表面に留まることができず、依然として消火効率が低く、再燃防止効果及び延焼抑制効果が十分とは言い難く、少ない消火剤の使用で効率良く消火活動を行うことができない。
【０００４】
かかる欠点を解消するため、水膨潤性ポリマー微粒子、含水ゲル等を使用した消火薬剤が報告されている（特許文献２）。しかしながら、これらは水不溶性の吸水性樹脂を添加しているため、一般に粘度が高く、消火機器の閉塞が起こりやすく、実用上においては極めて危険性を伴う。
【０００５】
そこで、これら不溶性樹脂にかえて、種々の水溶性高分子増粘剤が提案されている。例えば、特許文献３には、カルボキシメチルセルロースナトリウム塩、ポリアクリル酸ナトリウム塩、アルギン酸ナトリウム塩などを増粘剤として添加してなる水系消火薬剤が、また、特許文献４には、ポリアミン系水溶性高分子等が添加された水成膜性あるいは泡形成性の水系消火薬剤が提案されている。更に、アクリルアミド又はそれらのＮ−置換体をベースとする親水性ポリマーについても、例えば、特許文献５には、水溶性アクリルアミド誘導体を含むアニオン性共重合体が多糖ガムを含む極性溶剤泡沫消火剤組成物の粘度低減剤として使用できることが、特許文献６には、アクリルアミドあるいはＮ−置換アクリルアミドとフッ素化モノマーとの共重合体が乳化剤における添加剤として安定な泡を形成し特に極性液体の出火に有効なことが、それぞれ開示されている。
しかしながら、これらの消火薬剤は、燃焼物の表面に噴射されると、初期において一定の粘度を有するものの、火災の熱により容易に流下して、空気（酸素）隔離膜を形成できず、速やかに蒸発乾燥するため、再着火あるいは再燃しやすく、薬液を大量に噴射しない限り、充分な消火効果を挙げることができない。即ち、消火効果の持続性及び再着火防止性能の改善は必ずしも十分とは言えない。また、ポリアミン系水溶性高分子はアミンの骨格が酸化されやすく保存中変色変質してしまうという問題点が残り、フッ素化モノマーの使用はコストアップを招く。
【０００６】
本発明者らは、延焼及び消火用水の流失を防ぐために、常温では低粘度を有し、火災の熱により高温になると水を含んだままで不流動性になる水系消火薬剤を提案した（特許文献７）。これは主として感温性ポリマーと燐酸第二アンモニウムあるいはカリウム塩類などの組成からなるものであるが、使用される感温性ポリマーが、純水中において下限臨界溶液温度を示すものであるため、一定濃度以上の燐酸アンモニウムなどの塩を添加すると常温において不溶となり均一な溶液として得ることができず、初期消火力の向上に必要とされる塩の高濃度配合、即ち薬液の高濃度化調整には十分に対応できないという問題点があった。
【０００７】
【特許文献１】
特公昭５２−３７３１９号公報、同５８−５８１０７号公報、特開平１１−５７０５９号公報、同１１−１２８３８９号公報、同１１−１５５９７７号公報、同１１−２３５３９９号公報、特開２０００−４２１３２号公報、同２００２−２１９１９０号公報
【特許文献２】
特開平８−１０７９４６号公報、同９−１４０８２６号公報、同１０−１５５９３２号公報、同１１−２４４４１１号公報
【特許文献３】
特開平１−１６６７７７号公報
【特許文献４】
特開２０００−１２６３２７号公報、同２０００−３２５４９３号公報、同２００１−７９１０８号公報、同２００１−２６９４２１号公報、同２００１−３１４５２５号公報
【特許文献５】
特開平６−２５６６６９号公報
【特許文献６】
特開平９−２５３２３４号公報、同１０−１８２７５２号公報、特表２００２−５１７５３０号公報
【特許文献７】
特開２００１−１８７１６５号公報、同２００２−２９１９３９号公報
【０００８】
【発明が解決しようとする課題】
水系消火薬剤にかかる現状を踏まえて、本発明は、長期間保存しても、薬液の物性変化が起こることがなく、普通火災、油火災、森林火災、山火事などに対して少ない使用量でも優れた初期消火力を有するのみならず、驚異な再着火防止効果を有する水系消火薬剤並びにそれを用いる消火方法を提供するを課題とする。
【０００９】
【課題を解決するための手段】
本発明者等は、水系消火薬剤について鋭意研究した結果、一定濃度の燐酸塩、縮合燐酸塩などの消炎剤とこれらの消炎剤の存在下で下限臨界溶液温度を示すアミド系のポリマーを含有せしめることにより、かかる課題を解決できることを見いだし、本発明に到達した。
すなわち本発明は、
（１）純水中においては１００℃まで下限臨界溶液温度を有さず、塩存在下で下限臨界溶液温度を示す感温性ポリマーと、消炎剤とを、水に溶解した水系消火薬剤、
（２）塩存在下での下限臨界溶液温度が、５重量％燐酸二水素アンモニウムと５重量％燐酸水素二アンモニウムの混合水溶液中において、３５〜１００℃である、上記（１）記載の水系消火薬剤、
（３）感温性ポリマーが、ノニオン性ビニルモノマーの単独重合体又はノニオン性ビニルモノマーとイオン性ビニルモノマーの共重合体である、上記（１）乃至（２）記載の水系消火薬剤、
（４）ノニオン性ビニルモノマーが、ノニオン性アクリルアミド誘導体又はノニオン性ビニルアルキルアミドモノマーである、上記（１）乃至（３）のいずれか一に記載の水系消火薬剤、
（５）ノニオン性アクリルアミド誘導体が、Ｎ，Ｎ−ジメチルアクリルアミド、Ｎ−メチルアクリルアミド、Ｎ−アクリロイルモルホリンの中から選択される少なくとも１種以上である、上記（１）乃至（４）のいずれか一に記載の水系消火薬剤、
（６）ノニオン性ビニルアルキルアミドモノマーが、Ｎ−ビニルピロリドン、Ｎ−ビニルホルムアミド、Ｎ−ビニルアセトアミドの中から選択される少なくとも１種以上である、上記（１）乃至（４）のいずれか一に記載の水系消火薬剤、
（７）イオン性ビニルモノマーが、アニオン性ビニルモノマーである、上記（１）乃至（３）のいずれか一に記載の水系消火薬剤、
（８）消炎剤が、燐酸塩、縮合燐酸塩、硫酸塩、重炭酸塩、タングステン酸塩の中から選ばれる１種以上の化合物である、上記（１）乃至（４）のいずれか一に記載の水系消火薬剤、
（９）消炎剤の添加濃度が、５〜２０重量％の範囲である、上記（１）乃至（８）のいずれか一に記載の水系消火薬剤、
（１０）感温性ポリマーの１重量％水溶液の粘度が、５０〜１００００Ｐａ・ｓ（２５℃）である、上記（１）乃至（９）のいずれか一に記載の水系消火薬剤、
（１１）感温性ポリマーと消炎剤のほかに、湿潤浸透剤、防錆剤、氷結防止剤、着色剤、防腐剤のうち１種以上を更に配合してなる、上記（１）乃至（１０）のいずれか一に記載の水系消火薬剤、
（１２）水系消火薬剤の粘度が、５〜５０００ｍＰａ・ｓ（２５℃）である、上記（１）乃至（１１）のいずれか一に記載の水系消火薬剤、
（１３）上記（１）乃至（１２）のいずれか一に記載の水系消火薬剤を用いる消火方法、
（１４）水系消火薬剤を、予め５〜１００ｍＰａ・ｓ（２５℃）の粘度に調整し、噴射剤と共に消火機器に充填して被消火物に噴出する、上記（１３）記載の消火方法、
（１５）水系消火薬剤を、予め５〜１００ｍＰａ・ｓ（２５℃）の粘度に調整し、消防車、通常消防装置により被消火物に噴出する、上記（１３）記載の消火方法、
（１６）水系消火薬剤を、予め１０〜５０００ｍＰａ・ｓ（２５℃）の粘度に調整し、使用時希釈しながら、消防車又は通常消防装置により被消火物に噴出する、上記（１３）記載の消火方法、
を提供するものである。
【００１０】
【発明の実施の形態】
以下、本発明を詳細に説明する。
本発明の水系消火薬剤は、消炎剤として使用される化合物の水溶液に、これらの塩の存在下で下限臨界溶液温度を有するポリマーを併用配合したものであり、更に必要に応じて湿潤浸透剤、防錆剤、氷結防止剤、着色剤、防腐剤を添加してなるものである。
本発明のいう消炎剤とは、火災に対して防火性を示し、火災の消火に使用される水の消火能力を高める効果を有する有機塩化合物又は無機塩化合物をいう。
本発明に使用される物質の種類及び添加量の範囲並びにそれぞれの効能について説明する。
【００１１】
本発明に使用されるポリマーは、純水中においては１００℃まで下限臨界溶液温度を有さず、塩（消炎剤）の存在下で下限臨界溶液温度を有するもので（以下感温性ポリマーと称する）、５重量％燐酸二水素アンモニウムと５重量％燐酸水素二アンモニウムの混合水溶液中では下限臨界溶液温度を有するものが好ましい。
該感温性ポリマーの下限臨界溶液温度（増粘乃至ゲル化温度）は、季節や使用条件などにより異なるが、５重量％燐酸二水素アンモニウムと５重量％燐酸水素二アンモニウムの混合水溶液で測定した温度を、概ね３５〜１００℃に制御することが好ましい。
【００１２】
感温性ポリマーは、特に性能と入手の容易さを考慮すると、▲１▼ノニオン性ビニルモノマー、好ましくはノニオン性アクリルアミド誘導体又はノニオン性ビニルアルキルアミドモノマー、のホモポリマー、▲２▼ノニオン性ビニルモノマーとイオン性ビニルモノマーとのラジカル共重合体、が好ましい。
ビニルモノマーの重合を開始する方法としては、ラジカル重合開始剤を用いた熱又は光によるラジカル重合法、放射線重合法、電子線重合法、紫外線重合法等が挙げられ、また、重合方法としては、溶液重合法、懸濁重合法、逆相懸濁重合法、エマルション重合法、逆相エマルション重合法等が挙げられるが、通常、熱によるラジカル重合法と溶液重合法を使用することが好ましい。更に、重合は、攪拌しながら行ってもよく、静置状態で行ってもよい。尚、ビニルモノマーは、本発明にかかる消炎剤の存在下で重合させることもできる。
重合開始剤としてはラジカル重合を開始する能力を有するものであれば特に制限はなく、例えば、過硫酸アンモニウム、過硫酸ナトリウム、過硫酸カリウム等の過硫酸塩、過酸化水素、過酢酸、ｔ−ブチルパーオキサイド、ジ−ｔ−ブチルパーオキサイドなどの水溶性有機過酸化物、２，２’−アゾビス［２−（５−メチル−２−イミダゾリン−２−イル）プロパン］二塩酸塩（ＶＡ−０４１）、２，２’−アゾビス［２−（２−イミダゾリン−２−イル）プロパン］二塩酸塩（ＶＡ−０４４）、２，２’−アゾビス［２−（２−イミダゾリン−２−イル）プロパン］二硫酸塩（ＶＡ−０４６Ｂ）、２，２’−アゾビス［２−（３，４，５，６−テトラヒドロピリミジン−２−イル）プロパン］二塩酸塩（ＶＡ−０５８）、２，２’−アゾビス｛２−［１−（２−ヒドロキシエチル）−２−イミダゾリン−２−イル］プロパン｝二塩酸塩（ＶＡ−０６０）、２，２’−アゾビス［２−（２−イミダゾリン−２−イル）プロパン］（ＶＡ−０６１）、２，２’−アゾビス（２−メチルプロピオンアミジン）二塩酸塩（ＶＡ−５０）、２，２’−アゾビス［Ｎ−（２−カルボキシエチル）−２−メチル−プロピオンアミジン］（ＶＡ−０５７）、２，２’−アゾビス｛２−メチル−Ｎ−［１，１−ビス（ヒドロキシメチル）−２−ヒドロキシエチル］プロピオンアミド｝（ＶＡ−０８０）、２，２’−アゾビス｛２−メチル−Ｎ−［２−（１−ヒドロキシブチル）］−プロピオンアミド｝（ＶＡ−０８５）、２，２’−アゾビス［２−メチル−Ｎ−（２−ヒドロキシエチル）−プロピオンアミド］（ＶＡ−０８６）等の水溶性アゾ系化合物（熱分解型ラジカル重合開始剤）などを例示することができる。これらのラジカル重合開始剤は、単独で用いてもよく、二種類以上を併用してもよい。
また、これらのラジカル重合開始剤の分解を促進する還元剤を併用し、両者を組み合せることによりレドックス型開始剤（酸化還元型ラジカル重合開始剤）とすることもできる。還元剤としては、具体的には、例えば、亜硫酸水素ナトリウム、亜硫酸ナトリウムなどの亜硫酸塩、ナトリウムホルムアルデヒドスルホキシレート（ロンガリット）等の複合型還元性化合物、ハイドロサルファイトナトリウム、チオ硫酸ナトリウムなど還元性化合物、Ｌ−アスコルビン酸（塩）、第一鉄塩等の還元性金属（塩）、アミン類化合物等が挙げられるが、特に限定されるものではない。更に、これらのレドックス型重合開始剤とアゾ系重合開始剤は、単独で用いてもよく、二種類以上を併用してもよい。
【００１３】
用いられるノニオン性アクリルアミド誘導体としては、Ｎ，Ｎ−ジメチルアクリルアミド、Ｎ−メチルアクリルアミド、Ｎ−アクリロイルモルホリン等のアクリルアミド誘導体を例示することができる。またノニオン性ビニルアルキルアミドモノマーとしては、ビニルアセトアミド、ビニルホルムアミド、ビニルピロリドン等が例示される。これらのビニルモノマーは、単独で使用してもよく、二種類以上を併用してもよい。
これらのノニオン性ビニルモノマーは、塩水溶液中において下限臨界溶液温度を付与するために使用される成分であり、その割合は、ポリマー中の構成ビニルモノマーの総量に対して、８０モル％以上が好ましく、９５モル％以上が更に好ましい。これらのノニオン性ビニルモノマーの割合が８０モル％未満の場合には、昇温による感温性ポリマーの増粘乃至ゲル化性が著しく低下してしまうため、初期消火力の向上並びに再着火防止効果を達成できない。
【００１４】
また、イオン性ビニルモノマーは、感温性ポリマーの下限臨界溶液温度の高低並びに増粘乃至ゲル化後の保水力を制御するための成分であり、具体的には、例えば、（メタ）アクリル酸塩（アルカリ金属塩、アンモニウム塩）、２−（メタ）アクリルアミド−２−メチルプロパンスルホン酸塩（アルカリ金属塩、アンモニウム塩、アルカリ土類金属塩）、アクリルアミドエチルスルホン酸塩（アルカリ金属塩、アンモニウム塩、アルカリ土類金属塩）、ｐ−スチレンスルホン酸塩（アルカリ金属塩、アンモニウム塩、アルカリ土類金属塩）、ビニルスルホン酸塩（アルカリ金属塩、アンモニウム塩、アルカリ土類金属塩）、メタアリルスルホン酸塩（アルカリ金属塩、アンモニウム塩、アルカリ土類金属塩）、２−（メタ）アクリロイルオキシエタンスルホン酸塩（アルカリ金属塩、アンモニウム塩、アルカリ土類金属塩）、ビニルホスホン酸塩（アルカリ金属塩、アンモニウム塩）、モノ（２−（メタ）アクリロイルオキシエチル）アシッドホスフェート塩（アルカリ金属塩、アンモニウム塩）などのアニオン性ビニルモノマー、第３級アミノ基を有する（メタ）アクリレート誘導体由来の各種４級アンモニウム塩、第３級アミノ基を有する（メタ）アクリルアミド誘導体由来の各種４級アンモニウム塩などのカチオン性ビニルモノマー、第３級アミノ基を有する（メタ）アクリレート誘導体由来の各種両性イオン基を持つ分子内塩形成性単量体、第３級アミノ基を有する（メタ）アクリルアミド誘導体由来の各種両性イオン基を持つ分子内塩形成性単量体などの両性ビニルモノマー、アミノ酸塩を含むアクリルアミド誘導体などが挙げられるが、特に限定されるものではない。これらのイオン性ビニルモノマーは、単独で使用してもよく、また、二種類以上を併用してもよい。
これらのイオン性ビニルモノマーのうち、アニオン性ビニルモノマーが好ましく、アクリル酸のアルカリ金属塩、スルホン酸塩型のアニオン性ビニルモノマーがより好ましい。
【００１５】
感温性ポリマーは、その１重量％の２５℃における粘度が、５０〜１００００ｍＰａ・ｓを有することが好ましく、７０〜２５００ｍＰａ・ｓを有することがより好ましく、１００〜１０００ｍＰａ・ｓを有することが更に好ましい。
【００１６】
感温性ポリマーの添加量は、その共重合組成、重量平均分子量の大小、消炎剤の種類と添加量、並びに水系消火薬剤の粘度によって異なるが、主として水系消火薬剤に対して、０．０１〜２．５重量％が好ましく、０．０５〜１．５重量％がより好ましく、０．１〜１．０重量％が更に好ましい。
添加量が０．０１重量％未満の場合は、感温性ポリマーが十分な増粘乃至ゲル化効果を発揮できない恐れがあり、逆に、２．５重量％を超えると、有機成分の含有量が高く、消火に不利な影響を及ぼすのみならず、水系消火薬剤の粘度が高くなりすぎて、有効に使用できる消火機器又は消火器具が限定される。
【００１７】
本発明に使用される消炎剤は、具体的に例えば、燐酸二水素アンモニウム、燐酸水素二アンモニウム、燐酸水素アンモニウムナトリウム、燐酸グアニジン、燐酸と有機アミンの中和塩等の燐酸塩、縮合燐酸アンモニウム、縮合燐酸と有機アミンの中和塩等の縮合燐酸塩、硫酸アンモニウムなどの硫酸塩、炭酸水素アンモニウム、炭酸水素ナトリウム、炭酸水素カリウム等の重炭酸塩、タングステン酸ナトリウムなどのタングステン酸塩が例示されるが、消炎効果を有する塩類であれば、特に限定されるものではない。
これらの消炎剤は、単独で用いても良いが、相乗効果を引き出すために二種類以上を併用することが好ましい。消炎効果並びに経済性を考慮すると、燐酸二水素アンモニウム、燐酸水素二アンモニウムがより好ましい。
【００１８】
本発明にかかる水系消火薬剤は、使用時における消炎剤の含有量が５〜２０重量％の水溶液、好ましくは７〜２０重量％の水溶液として使用される。
消炎剤の濃度がそれ未満であると、消火効果を初期の目的通り発揮することが困難であり、一方、それを超えても効果の向上が見られず経済的に不利であり、また、感温性ポリマーが十分に溶解しない場合もある。
消炎剤はそれぞれ単独で使用しても良いが、混合して用いることが望ましい。混合割合は任意であるが、例えば、燐酸二水素アンモニウムと燐酸水素二アンモニウムの混合塩が５〜１８重量％、その他の消炎剤並びに添加剤が０〜２重量％となる範囲から選択することが好ましい。
【００１９】
本発明にかかる水系消火薬剤は、保存中の安定性、消火対象並びに使用環境により、必要に応じて湿潤浸透剤、防錆剤、氷結防止剤、着色剤、防腐剤を添加することができる。湿潤浸透剤は、ジアルキルスルホコハク酸ナトリウム、ラウリル硫酸アンモニウム、カルボキシベタイン、イミダゾリニウムベタインなどのベタイン型界面活性剤が挙げられるが、特に限定されるものではない。また、浸透性、界面張力低下能並びに塩（防炎剤）に対する相溶性を考慮すると、ジアルキルスルホコハク酸ナトリウム、ベタイン型の界面活性剤が好ましい。防錆剤は、タングステン酸ナトリウム、モリブデン酸ナトリウム、亜硝酸ナトリウム、安息香酸ナトリウム、モノエタノールアミン、ジエタノールアミン、トリエタノールアミン、１，２，３−ベンゾトリアゾールなどが挙げられるが、特に限定されるものではない。これらの防錆性は、単独で用いてもよく、二種類以上併用してもよい。氷結防止剤は、エタノール、イソプロパノール、エチレングリコール、プロピレングリコール、グリセリン、ＰＥＧ２００、尿素などが挙げられるが、特に限定されるものではない。これらの氷結防止剤の中で、エチレングリコール、グリセリンが特に好ましい。着色剤は、一般に森林火災、山火事等大規模火災の消火活動を行うときに、空中散布した薬液の飛行軌跡や着地位置を確認するために添加使用されているものであり、一般に親水性又は水溶性の顔料や染料等であれば、特に限定されるものではない。防腐剤は、水溶性臭化テトラメチルアンモニウム塩、臭化テトラメチルホスホニウム塩、銀や銅、亜鉛などの金属を主体とする防腐剤などが好適に使用することができる。
【００２０】
本発明の水系消火薬剤の各成分の作用は以下の通りである。
（１）塩の存在下で下限臨界溶液温度を有する感温性ポリマーは、火災の熱により一定濃度以上の消炎剤の塩水溶液と共に増粘乃至ゲル化することができ、空気を遮断する不流動性のゲル化隔離層が形成され、燃焼物の表面で長時間滞留することができるばかりではなく、高い保水性を有するため持続的な冷却作用及び空気遮断効果を発揮する。即ち、少ない消火薬剤の使用量で鎮火可能となり、高い消火効率を達成でき、消火力の一層向上を実現できる。また、これらの感温性ポリマーは、使用量の変更により、水系消火薬剤の粘度を任意に調整することができる。更に、これらの感温性ポリマーの使用により、従来初期消火能力の向上に必要とされる燐酸塩又は縮合燐酸塩の高濃度添加は、不要となる。
（２）燐酸塩や縮合燐酸塩等に代表される消炎剤、特にこれらのアンモニウム塩は、従来から一般火災や林野火災に対して優れた消火作用を持つことが知られており、且つ安価、高い安全性などの優位性を有するため、消火並びに消防活動に幅広く使用されてきた。これらの消炎剤は、上記感温性ポリマーの増粘乃至ゲル化特性を誘起させることができるため、火災に対する消火能力の一層向上を実現させることができる。また、ｐＨも中性領域にあり、人畜や環境に対して極めて安全である。消炎剤の添加量の適切範囲は、５〜２０重量％である。
（３）硫酸アンモニウムなどの硫酸塩や炭酸水素アンモニウム、炭酸水素ナトリウム、炭酸水素カリウム等の重炭酸塩は、燐酸塩又は縮合燐酸塩との相乗効果により、火災に対して消炎効果を一層向上させることができる。また、これらの塩は、比較的低い分解温度を有し、且つ分解後二酸化炭素や水などのガスが発生するので、空気（酸素）が排除され、燃焼が抑制されるため、消火作用の一翼を担うものである。
（４）タングステン酸ナトリウムなどのタングステン酸塩は、上記消炎剤との相乗作用を有するのみならず、鉄鋼類の金属に対して優れた防錆効果を示し、水系消火薬剤の中で、重要な役割を果たすものである。
（５）必要に応じて添加される湿潤浸透剤、防錆剤、氷結防止剤、着色剤、防腐剤は、使用条件に合わせて、水系消火薬剤の性能を向上させるために必要なものである。
【００２１】
本発明の水系消火薬剤の調整方法は任意であるが、例えば、所定量の塩（消炎剤）を溶解した水溶液に、特定の濃度の感温性ポリマー水溶液を加え均一に混合させる方法、特定の濃度の感温性ポリマー水溶液に、防炎剤の水溶液を加え均一に混合させる方法、等を挙げることができる。
【００２２】
本発明の水系消火薬剤は、バケツなどの容器に収納しておき、単純に火元に向けて散布することも可能であるが、キャリアガスによって水系消火薬剤を火元に散布するような消火機器又は消火器具を利用して使用することもでき、ポンプなどの動力源によって水系消火薬剤を火元に噴射するような消防自動車を利用して使用することもできる。更に、予め高濃度に調製した水系消火薬液は、消防車又はヘリコプターなどの貯蔵室に貯めておき、消火時に希釈混合させながら火元に噴射散布することもできる。
消火機器又は消火器具としては、本発明の水系消火薬剤、水系消火薬剤を収納する収納容器及び水系消火薬剤を収納容器から噴出させる圧縮された窒素ガス、二酸化炭素ガス等のキャリアガスとを有した消火機器又は消火器具、例えば小型消火器、大型消火器、エアゾール式簡易消火具等が例示される。また、特殊消火機器としては、インパルス消火機器やハイドレックス消火機器などが挙げられる。
【００２３】
本発明の水系消火薬剤の初期調製濃度に関しては、上述した消火方法に併せて任意に調整することができる。例えば、消火に使用する使用濃度に合わせて調整すれば、原液のままで使用することができ、貯蔵性を考慮すると予め高濃度に調製して、使用直前に所要濃度に希釈して用いることができる。
また、本発明の水系消火薬剤の初期調製粘度は、防炎剤の種類、濃度、感温性ポリマーの組成、添加量の変更によって、５〜５０００ｍＰａ・ｓ（２５℃）の範囲に任意に制御することができ、その使用時の粘度（２５℃）は、消火機器、消火器具などの特性によって異なるが、具体的に、例えば、小型消火器に充填使用される場合は、水系消火薬剤の粘度が５〜１００ｍＰａ・ｓであることが好ましく、５〜６０ｍＰａ・ｓであることがより好ましい。また、エアゾール式簡易消火器具に充填使用される場合は、水系消火薬剤の粘度が５〜５０ｍＰａ・ｓであることが好ましく、５〜３０ｍＰａ・ｓであることがより好ましい。これらの小型消火機器に使用される場合は、上記粘度が５ｍＰａ・ｓ未満であると、十分な消火力を奏することができず、逆に上記粘度以上になると噴射性が大きく低下してしまうため、実用上において不都合を生じる。
【００２４】
【実施例】
以下、実施例を挙げて本発明を詳細に説明する。なお、本発明はこれらの例によって限定されるものではない。
合成例１：ポリマーＡ１−１の合成
１Ｌ容量のセパラブルフラスコにＮ，Ｎ−ジメチルアクリルアミド（ＤＭＡＡ）１２０ｇ、脱イオン水６００ｇを加えて、攪拌しながら５重量％の硫酸水溶液を徐々に添加し、溶液のｐＨを７．３０に合わせ、中和操作を行った後、モノマー水溶液の濃度が１５重量％になるように、脱イオン水を補填した。そして、モノマー調製液を、２０℃の恒温槽に入れ、マグネチックスターラーで攪拌しながら窒素ガスをバブリングし、１時間通気した。そこで、重合開始剤としてＶＡ−０４４の５重量％水溶液を２．７４０ｇ、ロンガリットの５重量％水溶液を３．７３１ｇ、ｔｅｒｔ−ブチルヒドロペルオキシド（ｔ−ＢＨＰＯ）の５重量％水溶液を２．１８２ｇ順次投入し、２０℃にて重合反応を開始させた。５分後、攪拌並びに窒素ガスの通気を止め、密閉状態で室温下１６時間重合反応を続けた後、８５重量％の水を含む水あめ状のポリマーＡ１−１を得た。さらにＡ１−１を裁断し、脱イオン水に溶解させ、１、２、５重量％の水溶液をそれぞれ調製した。
【００２５】
合成例２：ポリマーＡ１−２の合成
１Ｌ容量のセパラブルフラスコにＮ，Ｎ−ジメチルアクリルアミド（ＤＭＡＡ）１２０ｇ、脱イオン水６００ｇを加えて、攪拌しながら５重量％の硫酸水溶液を徐々に添加し、溶液のｐＨを７．３０に合わせ、中和操作を行った後、モノマー水溶液の濃度が１５重量％になるように、脱イオン水を補填した。そして、モノマー調製液を、０℃の恒温槽に入れ、マグネチックスターラーで攪拌しながら窒素ガスをバブリングし、１時間通気した。そこで、重合開始剤としてＶＡ−０４４の５重量％水溶液を２．７４０ｇ、ロンガリットの５重量％水溶液を１．８６６ｇ、ｔｅｒｔ−ブチルヒドロペルオキシド（ｔ−ＢＨＰＯ）の５重量％水溶液を１．０９１ｇ順次投入し、２０℃にて重合反応を開始させた。５分後、攪拌並びに窒素ガスの通気を止め、密閉状態で室温下１６時間重合反応を続けた後、８５重量％の水を含む水あめ状のポリマーＡ１−２を得た。さらにＡ１−２を裁断し、脱イオン水に溶解させ、１、２、５重量％の水溶液をそれぞれ調製した。
【００２６】
合成例３：ポリマーＡ２−１の合成
１Ｌ容量のセパラブルフラスコにＮ−メチルアクリルアミド（ＮＭＡＡ）１２０ｇ、脱イオン水６００ｇを加えて、攪拌しながら５重量％の硫酸水溶液を徐々に添加し、溶液のｐＨを７．３０に合わせ、中和操作を行った後、モノマー水溶液の濃度が１５重量％になるように、脱イオン水を補填した。モノマー調製液を２０℃の恒温槽に入れ、マグネチックスターラーで攪拌しながら窒素ガスをバブリングし、１時間通気した。そこで、ＶＡ−０４４の５重量％水溶液を４．５５９ｇ、ロンガリットの５重量％水溶液を４．３４６ｇ、ｔ−ＢＨＰＯの５重量％水溶液を２．５４２ｇ順次投入し、２０℃にて重合反応を開始させた。５分後、攪拌並びに窒素ガスの通気を止め、密閉状態で室温下１６時間重合反応を続けた後、８５重量％の水を含む水あめ状のポリマーＡ２−１を得た。さらにＡ２−１を裁断し、脱イオン水に溶解させ、１、２、５重量％の水溶液をそれぞれ調製した。
【００２７】
合成例４：ポリマーＡ２−２の合成
１Ｌ容量のセパラブルフラスコにＮ−メチルアクリルアミド（ＮＭＡＡ）１２０ｇ、脱イオン水６００ｇを加えて、攪拌しながら５重量％の硫酸水溶液を徐々に添加し、溶液のｐＨを７．３０に合わせ、中和操作を行った後、モノマー水溶液の濃度が１５重量％になるように、脱イオン水を補填した。モノマー調製液を２０℃の恒温槽に入れ、マグネチックスターラーで攪拌しながら窒素ガスをバブリングし、１時間通気した。そこで、ＶＡ−０４４の５重量％水溶液を４．５５９ｇ、ロンガリットの５重量％水溶液を２．１７３ｇ、ｔ−ＢＨＰＯの５重量％水溶液を１．２７１ｇ順次投入し、０℃にて重合反応を開始させた。５分後、攪拌並びに窒素ガスの通気を止め、密閉状態で室温下１６時間重合反応を続けた後、８５重量％の水を含む水あめ状のポリマーＡ２−１を得た。さらにＡ２−１を裁断し、脱イオン水に溶解させ、１、２、５重量％の水溶液をそれぞれ調製した。
【００２８】
合成例５：ポリマーＡ３の合成
１Ｌ容量のセパラブルフラスコにＤＭＡＡ６４．５７ｇ、ＮＭＡＡ５５．４３ｇ、脱イオン水６００ｇを加えて、合成例２と同様に中和操作を行い、１５重量％のモノマー水溶液を調製した。これを２０℃の恒温槽に入れ、同様に窒素ガスを１時間通気した。そこで、ＶＡ−０４４の５重量％水溶液を４．２１２ｇ、ロンガリットの５重量％水溶液を４．０１５ｇ、ｔ−ＢＨＰＯの５重量％水溶液を２．３４８ｇ順次投入し、２０℃にて重合反応を開始させた。５分後、攪拌並びに窒素ガスの通気を止め、密閉状態で室温下１６時間重合反応を続けた後、８５重量％の水を含む水あめ状のポリマーＡ３を得た。さらにＡ３を裁断し、脱イオン水に溶解させ、１、２、５重量％の水溶液をそれぞれ調製した。
【００２９】
合成例６：ポリマーＡ４の合成
１Ｌ容量のセパラブルフラスコにＤＭＡＡ１２０ｇ、アクリル酸（ＡＡｃ）０．８８１ｇ、脱イオン水６００ｇを加えて、攪拌しながら５重量％の水酸化カリウム水溶液を徐々に添加し、溶液のｐＨを７．３０に合わせ、中和操作を行った後、モノマー水溶液の濃度が１５重量％になるように、脱イオン水を補充した。モノマー調製液を２０℃の恒温槽に入れ、マグネチックスターラーで攪拌しながら窒素ガスをバブリングし、１時間通気した。そこで、ＶＡ−０４４の５重量％水溶液を２．７６７ｇ、ロンガリットの５重量％水溶液を５．６５４ｇ、ｔ−ＢＨＰＯの５重量％水溶液を３．３０６ｇ順次投入し、２０℃にて重合反応を開始させた。５分後、攪拌並びに窒素ガスの通気を止め、密閉状態で室温下１６時間重合反応を続けた後、８５重量％の水を含む水あめ状のポリマーＡ４を得た。さらにＡ４を裁断し、脱イオン水に溶解させ、１、２、５重量％の水溶液をそれぞれ調製した。
【００３０】
合成例７：ポリマーＡ５〜７の合成
１Ｌ容量のセパラブルフラスコにＤＭＡＡ１２０ｇ、ＡＡｃ２．６９８ｇ、脱イオン水６００ｇを加えて、合成例６と同様に中和操作を行い、１５重量％のモノマー水溶液を三つ調製した。それぞれを０、１３、２０℃の恒温槽に入れ、同様に窒素ガスを１時間通気した。その後、ＶＡ−０４４の５重量％水溶液を２．８２４ｇ、ロンガリットの５重量％水溶液を３．８４７ｇ、ｔ−ＢＨＰＯの５重量％水溶液を２．２４９ｇ順次投入し、それぞれ０、１３、２０℃にて重合反応を開始させた。５分後、攪拌並びに窒素ガスの通気を止め、密閉状態で室温下１６時間重合反応を続けた後、８５重量％の水を含む水あめ状のポリマーＡ５、Ａ６、Ａ７を得た。さらにＡ５〜７を裁断し、脱イオン水に溶解させ、各々の１、２、５重量％の水溶液をそれぞれ調製した。
【００３１】
前記ポリマーＡ１〜７の組成、重合開始温度及び１重量％水溶液の粘度を表１に纏めた。
【００３２】
【表１】

【００３３】
実施例１〜２５、比較例１〜１３
合成例１〜７で得られた、１、２、又は５重量％のポリマー水溶液に、燐酸二水素アンモニウム、燐酸水素二アンモニウムなどの防炎剤の水溶液を加え、均一に混合させて、本発明の原液型水系消火薬剤を調製した。
また、使用時に希釈しながら消火活動に使用できる濃縮型の水系消火薬剤を調製した。
本発明の水系消火薬剤の組成並びに物性を表２、表３、表４に示す。
【００３４】
【表２】

【００３５】
【表３】

【００３６】
【表４】

【００３７】
この結果から、明らかのように、▲１▼ポリマーの組成と配合濃度、消炎剤の種類と濃度を変更することで、水系消火薬剤の下限臨界溶液温度並びに粘度を任意に制御できる、▲２▼消炎剤の濃度が２０重量％を超えるとポリマーの溶解性は著しく低下し、水系消火薬剤の調製は不能となった。▲３▼水系消火薬剤を予め高濃度に調製することができ、且つ希釈後の水系消火薬剤の物性が殆ど変わらず、大規模火災の消火用に好都合である。
【００３８】
比較例１４〜１９
本発明の水系消火薬剤と比較するための比較の水系消火薬剤の組成を表５に示す。
【００３９】
【表５】

【００４０】
評価例１
上記実施例及び比較例に基づく水系消火薬剤を用いて、住宅用水消火器に充填して、圧縮空気を用いて消火器の内圧を７ｋｇｆ／ｃｍ^２に加圧し、２５℃における噴射試験を行い、放射距離を確認した。その結果を表６に記す。
【００４１】
【表６】

【００４２】
表６から明らかなように、住宅用水消火器に充填される水系消火薬剤の粘度が高すぎると、噴射が困難であり、噴射距離も短くなってしまうため、消火活動に著しく支障を生じることが分かる。
【００４３】
評価例２
本発明の水系消火薬剤１．５ｋｇを評価例１と同様の条件で充填した消火器を用いて、木材火災、天ぷら油火災に対する消火試験を行った。
なお、木材消火試験は、消火器の技術上の規格を定める省令に基づき行った。即ち、３５×３０×４５０ｍｍの杉の気乾材を５本・５本・４本・４本・５本・５本・・・・・・４本・４本と井桁状に７２本組み、高さ３０ｃｍ幅４５０×４５０ｍｍの架台に置き、燃焼なべに予燃焼剤として０．６リットルのノルマルヘプタンを入れ、３分間燃焼させた後に消火を開始し消火状況と消火後の再着火の有無の確認試験を行った。
結果を表７に記す。
【００４４】
【表７】

【００４５】
評価例３
本発明の水系消火薬剤５００ｇを評価例１と同様の条件で充填した消火器を用いて、天ぷら油火災に対する消火試験を行った。
天ぷら油消火試験も、同様に消火器の技術上の規格を定める省令に基づき行った。即ち、直径３００ｍｍ深さ７５ｍｍの中華鍋に１リットルの大豆油を入れてガスコンロで加熱発火させ、油の温度が４００℃になった時点で消火を開始した。そして、噴射直後から消火に至るまでの時間を消火時間として計測し、更に消火時の炎の立ち上がりの有無、再着火の有無、並びに消火後油の表面状態について試験を行った。
結果を表８に記す。
なお、表８における消火可否の基準は、以下の通りである。
○：消火可、×：消火不可（５００ｇ全量噴射しても、消火できない）
【００４６】
【表８】

【００４７】
以上の各実施例と比較例から明らかなように、本発明による水系消火薬剤は、木材火災、天ぷら油火災に対して優れた消火性能を発揮し、少ない消火薬剤の使用量で効率よく消火活動を遂行することができる。
【００４８】
【発明の効果】
本発明の水系消火薬剤は、火災の熱により増粘乃至ゲル化を起こすことによって、燃焼物の表面に対する付着性が著しく向上し、緻密な皮膜を形成できる。これによって、空気（酸素）を遮断し、持続的な消火力を発揮することができ、消火後再着火を充分に防止することができるという極めて優れた効果を奏し、木材火災、てんぷら油火災の消火に確実に対応できる。更に、本発明によれば、少量の放出でも消火活動を実施することができ、水損防止効果を有し、且つｐＨも中性付近であるので、消火性能が優れるのみならず、安全性の高い水系消火薬剤を提供することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention uses a temperature-sensitive polymer and a flame retardant in combination, and can perform an effective fire extinguishing activity with a small amount of water. Moreover, the water loss is remarkably reduced, and the fire extinguishing performance and the reignition prevention performance are excellent. The present invention relates to a water-based fire extinguishing agent and a fire extinguishing method using the same.
[0002]
[Prior art]
As a general fire extinguishing means, there is a method of radiating fresh water toward a fire source. This not only removes a large amount of heat (evaporation latent heat) from the evaporation of water and cools the combustion product to a temperature below the ignition temperature, but also removes the latent heat of evaporation from the combustion product and evaporates, thereby increasing the volume by about 1700 times. This is because there is also a so-called suffocation effect that shuts off air to the combustion products by the generated water vapor, making it easier to extinguish the fire. However, most of the water applied to the combusted material flows down, and the fire extinguishing efficiency is extremely low. Therefore, continuous water discharge is required and it takes time to extinguish the fire.
[0003]
Numerous studies have been conducted to improve the fire fighting performance of fresh water, mainly by adding high concentrations of inorganic salts, organic salts, neutralized salts of phosphoric acid and organic amines, and various surfactants that have a flame-retardant effect. (Patent Document 1). However, although these water-based fire extinguishing agents have improved the initial fire extinguishing performance, they cannot remain on the surface of the combusted material, and still have low fire extinguishing efficiency, and it is difficult to say that the reflaming prevention effect and the fire spread suppressing effect are sufficient and few. Fire extinguishing activities cannot be performed efficiently using fire extinguishing agents.
[0004]
In order to eliminate such drawbacks, a fire extinguishing agent using water-swellable polymer fine particles, hydrous gel, etc. has been reported (Patent Document 2). However, since a water-insoluble water-absorbent resin is added to these, the viscosity is generally high, and fire-extinguishing equipment is likely to be clogged, which is extremely dangerous in practical use.
[0005]
Therefore, various water-soluble polymer thickeners have been proposed in place of these insoluble resins. For example, Patent Document 3 discloses an aqueous fire extinguishing agent obtained by adding carboxymethylcellulose sodium salt, polyacrylic acid sodium salt, sodium alginate and the like as a thickener, and Patent Document 4 discloses a polyamine water-soluble high-water-soluble agent. Water-based film-forming or foam-forming water-based fire extinguishing agents to which molecules are added have been proposed. Further, for hydrophilic polymers based on acrylamide or N-substituted products thereof, for example, Patent Document 5 discloses a polar solvent foam fire extinguisher composition in which an anionic copolymer containing a water-soluble acrylamide derivative contains a polysaccharide gum. Patent Document 6 discloses that a copolymer of acrylamide or N-substituted acrylamide and a fluorinated monomer forms a stable foam as an additive in an emulsifier, and is particularly effective for the ignition of polar liquids. Each is disclosed.
However, these fire extinguishing agents have a certain viscosity at the initial stage when injected onto the surface of the combustion product, but they easily flow down due to the heat of the fire and cannot form an air (oxygen) isolating film. Since it evaporates and dries, it is easy to re-ignite or re-flame, and a sufficient fire-extinguishing effect cannot be obtained unless a large amount of chemical is injected. That is, the improvement of the sustainability of the fire-extinguishing effect and the performance of preventing reignition is not necessarily sufficient. In addition, polyamine-based water-soluble polymers still have the problem that the amine skeleton is easily oxidized and discolors during storage, and the use of fluorinated monomers increases the cost.
[0006]
The present inventors have proposed a water-based fire extinguishing agent that has low viscosity at room temperature and becomes non-flowable while containing water when heated to high temperatures due to fire heat in order to prevent the spread of fire spread and fire extinguishing water (Patent Literature). 7). This is mainly composed of a temperature-sensitive polymer and a composition such as diammonium phosphate or potassium salt, but since the temperature-sensitive polymer used exhibits a lower critical solution temperature in pure water, it is constant. When adding salt such as ammonium phosphate above the concentration, it becomes insoluble at room temperature and cannot be obtained as a uniform solution, and it is necessary to adjust the concentration of the chemical solution to a high concentration, that is, to improve the initial fire extinguishing power. There was a problem that it was not able to respond sufficiently.
[0007]
[Patent Document 1]
JP-B-52-37319, JP-A-58-58107, JP-A-11-57059, JP-A-11-128389, JP-A-11-155777, JP-A-11-235399, JP-A-2000-42132 Gazette, 2002-219190 gazette
[Patent Document 2]
JP-A-8-107946, JP-A-9-140826, JP-A-10-155932, JP-A-11-244411
[Patent Document 3]
JP-A-1-166777
[Patent Document 4]
JP-A-2000-126327, 2000-325493, 2001-79108, 2001-269421, 2001-314525
[Patent Document 5]
JP-A-6-256669
[Patent Document 6]
JP-A-9-253234, JP-A-10-182275, JP-T-2002-517530
[Patent Document 7]
Japanese Patent Application Laid-Open Nos. 2001-187165 and 2002-291939
[0008]
[Problems to be solved by the invention]
Based on the current situation concerning water-based fire extinguishing agents, the present invention does not change the physical properties of chemicals even if stored for a long period of time, and even with a small amount of use for ordinary fires, oil fires, forest fires, forest fires, etc. It is an object of the present invention to provide a water-based fire extinguishing agent that not only has an excellent initial fire extinguishing power but also has an amazing reignition prevention effect, and a fire extinguishing method using the same.
[0009]
[Means for Solving the Problems]
As a result of diligent research on water-based fire extinguishing agents, the present inventors include flame retardants such as phosphates and condensed phosphates at a certain concentration, and amide-based polymers that exhibit a lower critical solution temperature in the presence of these flame retardants. Thus, the present inventors have found that such a problem can be solved, and have reached the present invention.
That is, the present invention
(1) A water-based fire extinguishing agent in which a thermosensitive polymer having a lower critical solution temperature in the presence of salt and a flame retardant is dissolved in water without having a lower critical solution temperature up to 100 ° C. in pure water,
(2) The water-based fire extinguishing according to the above (1), wherein the lower critical solution temperature in the presence of salt is 35 to 100 ° C. in a mixed aqueous solution of 5% by weight ammonium dihydrogen phosphate and 5% by weight diammonium hydrogen phosphate. Drugs,
(3) The water-based fire extinguishing agent according to the above (1) to (2), wherein the temperature-sensitive polymer is a homopolymer of a nonionic vinyl monomer or a copolymer of a nonionic vinyl monomer and an ionic vinyl monomer,
(4) The water-based fire extinguishing agent according to any one of (1) to (3), wherein the nonionic vinyl monomer is a nonionic acrylamide derivative or a nonionic vinyl alkylamide monomer,
(5) Any one of the above (1) to (4), wherein the nonionic acrylamide derivative is at least one selected from N, N-dimethylacrylamide, N-methylacrylamide, and N-acryloylmorpholine. Water-based fire extinguishing agent according to
(6) Any one of the above (1) to (4), wherein the nonionic vinylalkylamide monomer is at least one selected from N-vinylpyrrolidone, N-vinylformamide, and N-vinylacetamide. Water-based fire extinguishing agent according to
(7) The water-based fire extinguishing agent according to any one of (1) to (3), wherein the ionic vinyl monomer is an anionic vinyl monomer,
(8) Any one of the above (1) to (4), wherein the flame retardant is at least one compound selected from phosphates, condensed phosphates, sulfates, bicarbonates, and tungstates. The water-based fire extinguishing agent described,
(9) The aqueous fire extinguishing agent according to any one of (1) to (8) above, wherein the addition concentration of the flame retardant is in the range of 5 to 20% by weight,
(10) The water-based fire extinguishing agent according to any one of (1) to (9) above, wherein the viscosity of a 1% by weight aqueous solution of the temperature-sensitive polymer is 50 to 10,000 Pa · s (25 ° C.),
(11) In addition to the temperature-sensitive polymer and the anti-inflammatory agent, the above (1) to (10), wherein one or more of a wet penetrant, a rust inhibitor, an anti-icing agent, a colorant, and an antiseptic are further blended. ) Water-based fire extinguishing agent according to any one of
(12) The water-based fire extinguishing agent according to any one of (1) to (11) above, wherein the viscosity of the water-based fire extinguishing agent is 5 to 5000 mPa · s (25 ° C.),
(13) A fire extinguishing method using the water-based fire extinguishing agent according to any one of (1) to (12) above,
(14) The fire extinguishing method according to (13) above, wherein the water-based fire extinguishing agent is adjusted in advance to a viscosity of 5 to 100 mPa · s (25 ° C.), filled in a fire extinguishing device together with a propellant, and ejected to a fire extinguisher.
(15) The fire extinguishing method according to (13) above, wherein the water-based fire extinguishing agent is adjusted in advance to a viscosity of 5 to 100 mPa · s (25 ° C.), and is jetted onto the fire extinguisher by a fire truck or a normal fire fighting device.
(16) The water-based fire extinguishing agent is adjusted to a viscosity of 10 to 5000 mPa · s (25 ° C.) in advance, and is jetted onto a fire extinguisher by a fire truck or a normal fire fighting apparatus while being diluted during use. Fire extinguishing method,
Is to provide.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
The water-based fire extinguishing agent of the present invention is a combination of a polymer having a lower critical solution temperature in the presence of these salts in an aqueous solution of a compound used as a flame retardant, and a wet penetrant, if necessary. A rust preventive, an anti-icing agent, a colorant, and a preservative are added.
The flame retardant according to the present invention refers to an organic salt compound or an inorganic salt compound that has an effect of enhancing fire extinguishing ability of water used for extinguishing fires.
The types of substances used in the present invention, the ranges of the amounts added, and the effects of each will be described.
[0011]
The polymer used in the present invention does not have a lower critical solution temperature up to 100 ° C. in pure water, and has a lower critical solution temperature in the presence of a salt (anti-inflammatory agent) (hereinafter referred to as a thermosensitive polymer). In the mixed aqueous solution of 5 wt% ammonium dihydrogen phosphate and 5 wt% diammonium hydrogen phosphate, those having a lower critical solution temperature are preferable.
The lower critical solution temperature (thickening or gelling temperature) of the thermosensitive polymer was measured with a mixed aqueous solution of 5% by weight ammonium dihydrogen phosphate and 5% by weight diammonium hydrogen phosphate, depending on the season and use conditions. It is preferable to control the temperature to approximately 35 to 100 ° C.
[0012]
In view of performance and availability, the thermosensitive polymer is, in particular, (1) a nonionic vinyl monomer, preferably a homopolymer of a nonionic acrylamide derivative or a nonionic vinyl alkylamide monomer, and (2) a nonionic vinyl monomer. And a radical copolymer of an ionic vinyl monomer.
Examples of the method for initiating the polymerization of the vinyl monomer include a radical polymerization method using heat or light using a radical polymerization initiator, a radiation polymerization method, an electron beam polymerization method, an ultraviolet polymerization method, and the like. Examples include solution polymerization, suspension polymerization, reverse phase suspension polymerization, emulsion polymerization, and reverse emulsion polymerization, and it is usually preferable to use a radical polymerization method and a solution polymerization method using heat. Furthermore, the polymerization may be performed with stirring or may be performed in a stationary state. The vinyl monomer can be polymerized in the presence of the flame retardant according to the present invention.
The polymerization initiator is not particularly limited as long as it has the ability to initiate radical polymerization. For example, persulfates such as ammonium persulfate, sodium persulfate, potassium persulfate, hydrogen peroxide, peracetic acid, t-butyl Water-soluble organic peroxides such as peroxide and di-t-butyl peroxide, 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride (VA-041) ), 2,2′-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride (VA-044), 2,2′-azobis [2- (2-imidazolin-2-yl) propane ] Disulfate (VA-046B), 2,2'-azobis [2- (3,4,5,6-tetrahydropyrimidin-2-yl) propane] dihydrochloride (VA-058), 2,2 ' -Azobis {2 [1- (2-hydroxyethyl) -2-imidazolin-2-yl] propane} dihydrochloride (VA-060), 2,2′-azobis [2- (2-imidazolin-2-yl) propane] ( VA-061), 2,2′-azobis (2-methylpropionamidine) dihydrochloride (VA-50), 2,2′-azobis [N- (2-carboxyethyl) -2-methyl-propionamidine] (VA-057), 2,2′-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide} (VA-080), 2,2′-azobis {2-Methyl-N- [2- (1-hydroxybutyl)]-propionamide} (VA-085), 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide] (VA And water-soluble azo compounds (thermally decomposable radical polymerization initiator) such as -086). These radical polymerization initiators may be used alone or in combination of two or more.
In addition, a reducing agent that promotes the decomposition of these radical polymerization initiators may be used in combination, and a combination of both may be used as a redox initiator (oxidation-reduction type radical polymerization initiator). Specific examples of the reducing agent include sulfites such as sodium bisulfite and sodium sulfite, complex-type reducing compounds such as sodium formaldehyde sulfoxylate (Longalite), reducing agents such as hydrosulfite sodium and sodium thiosulfate. Compounds, L-ascorbic acid (salt), reducing metals (salts) such as ferrous salts, amine compounds, and the like can be mentioned, but there is no particular limitation. Further, these redox polymerization initiators and azo polymerization initiators may be used alone or in combination of two or more.
[0013]
Examples of the nonionic acrylamide derivative used include acrylamide derivatives such as N, N-dimethylacrylamide, N-methylacrylamide, and N-acryloylmorpholine. Examples of nonionic vinylalkylamide monomers include vinylacetamide, vinylformamide, vinylpyrrolidone and the like. These vinyl monomers may be used alone or in combination of two or more.
These nonionic vinyl monomers are components used to impart a lower critical solution temperature in an aqueous salt solution, and the proportion thereof is preferably 80 mol% or more based on the total amount of constituent vinyl monomers in the polymer. 95 mol% or more is more preferable. When the ratio of these nonionic vinyl monomers is less than 80 mol%, the increase in initial fire extinguishing power and the prevention of re-ignition are caused because the increase in viscosity or gelation of the temperature-sensitive polymer due to temperature rise is significantly reduced. Cannot be achieved.
[0014]
The ionic vinyl monomer is a component for controlling the lower critical solution temperature of the thermosensitive polymer and the water retention after thickening or gelation. Specifically, for example, (meth) acrylic acid Salt (alkali metal salt, ammonium salt), 2- (meth) acrylamide-2-methylpropane sulfonate (alkali metal salt, ammonium salt, alkaline earth metal salt), acrylamide ethyl sulfonate (alkali metal salt, ammonium) Salt, alkaline earth metal salt), p-styrene sulfonate (alkali metal salt, ammonium salt, alkaline earth metal salt), vinyl sulfonate (alkali metal salt, ammonium salt, alkaline earth metal salt), meta Allyl sulfonate (alkali metal salt, ammonium salt, alkaline earth metal salt), 2- (meth) acryloyloxy Ethane sulfonate (alkali metal salt, ammonium salt, alkaline earth metal salt), vinyl phosphonate (alkali metal salt, ammonium salt), mono (2- (meth) acryloyloxyethyl) acid phosphate salt (alkali metal salt) , Ammonium salts), various quaternary ammonium salts derived from (meth) acrylate derivatives having tertiary amino groups, and various quaternary ammonium salts derived from (meth) acrylamide derivatives having tertiary amino groups Cationic vinyl monomers such as, derived from (meth) acrylate derivatives having tertiary amino groups, various intramolecular salt-forming monomers derived from zwitterionic groups, derived from (meth) acrylamide derivatives having tertiary amino groups Amphoteric vinyl monomers such as internal salt-forming monomers with various zwitterionic groups Chromatography, although acrylamide derivatives containing amino acid salts, but is not particularly limited. These ionic vinyl monomers may be used alone or in combination of two or more.
Among these ionic vinyl monomers, anionic vinyl monomers are preferable, and alkali metal salts of acrylic acid and sulfonic acid salt type anionic vinyl monomers are more preferable.
[0015]
The temperature-sensitive polymer preferably has a 1% by weight viscosity at 25 ° C. of 50 to 10,000 mPa · s, more preferably 70 to 2500 mPa · s, and more preferably 100 to 1000 mPa · s. preferable.
[0016]
The addition amount of the temperature-sensitive polymer varies depending on the copolymer composition, the size of the weight average molecular weight, the type and addition amount of the flame retardant, and the viscosity of the water-based fire extinguishing agent. 2.5 weight% is preferable, 0.05-1.5 weight% is more preferable, 0.1-1.0 weight% is still more preferable.
If the amount added is less than 0.01% by weight, the temperature-sensitive polymer may not exhibit sufficient thickening or gelling effects. Conversely, if it exceeds 2.5% by weight, the content of organic components The water-based fire extinguishing agent becomes too high in viscosity, and the fire extinguishing apparatus or fire extinguishing apparatus that can be used effectively is limited.
[0017]
Specific examples of the flame retardant used in the present invention include, for example, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, sodium ammonium phosphate, guanidine phosphate, phosphates such as neutralized salts of phosphoric acid and organic amines, condensed ammonium phosphates, Examples include condensed phosphates such as neutralized salts of condensed phosphoric acid and organic amines, sulfates such as ammonium sulfate, bicarbonates such as ammonium bicarbonate, sodium bicarbonate and potassium bicarbonate, and tungstates such as sodium tungstate. However, it is not particularly limited as long as the salt has an anti-inflammatory effect.
These anti-inflammatory agents may be used alone, but it is preferable to use two or more kinds in combination in order to bring out a synergistic effect. In view of the flame extinguishing effect and economy, ammonium dihydrogen phosphate and diammonium hydrogen phosphate are more preferable.
[0018]
The water-based fire extinguishing agent according to the present invention is used as an aqueous solution having a flame retardant content of 5 to 20% by weight, preferably 7 to 20% by weight in use.
If the concentration of the flame retardant is less than that, it is difficult to exert the fire-extinguishing effect as intended, but if the concentration exceeds that, the improvement of the effect is not seen and it is economically disadvantageous. The warm polymer may not dissolve sufficiently.
Although each of the anti-inflammatory agents may be used alone, it is desirable to use them in combination. The mixing ratio is arbitrary, but for example, it is selected from the range in which the mixed salt of ammonium dihydrogen phosphate and diammonium hydrogen phosphate is 5 to 18% by weight, and other flame retardants and additives are 0 to 2% by weight. preferable.
[0019]
The water-based fire extinguishing agent according to the present invention can be added with a wetting penetrant, a rust inhibitor, an anti-icing agent, a colorant, and an antiseptic as required depending on the stability during storage, the fire extinguishing target, and the use environment. Examples of the wet penetrating agent include betaine surfactants such as sodium dialkylsulfosuccinate, ammonium lauryl sulfate, carboxybetaine, and imidazolinium betaine, but are not particularly limited. In consideration of permeability, interfacial tension reducing ability, and compatibility with salts (flameproofing agents), sodium dialkylsulfosuccinate and betaine type surfactants are preferred. Examples of the rust preventive include sodium tungstate, sodium molybdate, sodium nitrite, sodium benzoate, monoethanolamine, diethanolamine, triethanolamine, 1,2,3-benzotriazole, and the like. is not. These rust preventive properties may be used alone or in combination of two or more. Examples of the anti-icing agent include ethanol, isopropanol, ethylene glycol, propylene glycol, glycerin, PEG200, and urea, but are not particularly limited. Of these anti-icing agents, ethylene glycol and glycerin are particularly preferred. Colorants are generally used to confirm the flight trajectory and landing position of chemicals sprayed in the air when extinguishing large-scale fires such as forest fires and wildfires. It is not particularly limited as long as it is a water-soluble pigment or dye. As the preservative, a water-soluble tetramethylammonium bromide salt, a tetramethylphosphonium bromide salt, a preservative mainly composed of metals such as silver, copper, and zinc can be preferably used.
[0020]
The action of each component of the water-based fire extinguishing agent of the present invention is as follows.
(1) A thermosensitive polymer having a lower critical solution temperature in the presence of salt can be thickened or gelled together with a salt solution of a flame retardant having a certain concentration or more by the heat of a fire, and does not flow to block air In addition to being able to stay on the surface of the combustion product for a long time, it has a high water retention and exhibits a continuous cooling action and air blocking effect. That is, the fire can be extinguished with a small amount of extinguishing agent, high fire extinguishing efficiency can be achieved, and fire extinguishing power can be further improved. Moreover, these thermosensitive polymers can adjust the viscosity of a water-based fire extinguishing agent arbitrarily by changing the usage-amount. Furthermore, the use of these temperature-sensitive polymers eliminates the need for high concentration addition of phosphates or condensed phosphates conventionally required for improving the initial fire extinguishing ability.
(2) Flame retardants represented by phosphates, condensed phosphates, etc., especially these ammonium salts have been known to have an excellent fire fighting action against general fires and forest fires, and are inexpensive. Because of its superior safety and other advantages, it has been widely used for fire fighting and fire fighting activities. Since these flame retardants can induce thickening or gelling properties of the temperature-sensitive polymer, it is possible to realize further improvement in fire extinguishing ability against fire. Moreover, pH is also in a neutral region and is extremely safe for human livestock and the environment. An appropriate range of the addition amount of the anti-inflammatory agent is 5 to 20% by weight.
(3) Sulfates such as ammonium sulfate and bicarbonates such as ammonium hydrogen carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, etc., can further improve the fire-extinguishing effect against fire due to a synergistic effect with phosphate or condensed phosphate. Can do. In addition, these salts have a relatively low decomposition temperature, and gas such as carbon dioxide and water is generated after decomposition, so that air (oxygen) is excluded and combustion is suppressed. Is responsible for.
(4) Tungstates such as sodium tungstate not only have a synergistic effect with the above-mentioned flame retardants, but also show an excellent rust prevention effect against steel metals, and are important among water-based fire extinguishing agents. It plays a role.
(5) Wet penetrant, rust preventive, anti-icing agent, colorant, and preservative added as necessary are necessary to improve the performance of water-based fire extinguishing agents according to the use conditions. .
[0021]
The method for adjusting the water-based fire extinguishing agent of the present invention is arbitrary. For example, a method of adding a temperature-sensitive polymer aqueous solution having a specific concentration to an aqueous solution in which a predetermined amount of salt (anti-inflammatory agent) is dissolved, and uniformly mixing, Examples thereof include a method in which an aqueous solution of a flameproofing agent is added to a temperature-sensitive polymer aqueous solution having a concentration and mixed uniformly.
[0022]
The water-based fire extinguishing agent of the present invention is stored in a container such as a bucket and can be simply sprayed toward the fire source, but a fire extinguishing device that sprays the water-based fire extinguishing agent on the fire source with a carrier gas Or it can also be used using a fire extinguisher, and it can also be used using the fire engine which injects a water-system fire extinguishing agent to a fire source with power sources, such as a pump. Furthermore, the water-based fire extinguisher liquid prepared in advance at a high concentration can be stored in a storage room such as a fire truck or a helicopter, and sprayed and sprayed to the fire source while being diluted and mixed during fire extinguishing.
As a fire extinguishing device or fire extinguishing apparatus, the water-based fire extinguishing agent of the present invention, a storage container for storing the water-based fire extinguishing agent, and a carrier gas such as compressed nitrogen gas or carbon dioxide gas for ejecting the water-based fire extinguishing agent from the storage container. Examples include fire extinguishers or fire extinguishers, such as small fire extinguishers, large fire extinguishers, aerosol-type simple fire extinguishers, and the like. Examples of special fire extinguishing equipment include impulse fire extinguishing equipment and Hydrex fire extinguishing equipment.
[0023]
The initial preparation concentration of the water-based fire extinguishing agent of the present invention can be arbitrarily adjusted in accordance with the above-described fire extinguishing method. For example, if it is adjusted according to the concentration used for fire extinguishing, it can be used as it is as a stock solution. In consideration of storability, it should be prepared at a high concentration in advance and diluted to the required concentration just before use. it can.
The initial viscosity of the water-based fire extinguishing agent of the present invention is arbitrarily controlled in the range of 5 to 5000 mPa · s (25 ° C.) by changing the type, concentration, composition of the temperature-sensitive polymer, and addition amount of the flameproofing agent. The viscosity at the time of use (25 ° C.) varies depending on the characteristics of fire extinguishing equipment, fire extinguishing equipment, etc., but specifically, for example, when used in a small fire extinguisher, the viscosity of the water-based fire extinguishing agent Is preferably 5 to 100 mPa · s, and more preferably 5 to 60 mPa · s. Moreover, when filling and using for an aerosol-type simple fire extinguishing apparatus, it is preferable that the viscosity of a water-system fire extinguishing agent is 5-50 mPa * s, and it is more preferable that it is 5-30 mPa * s. When used in these small fire extinguishing equipment, if the viscosity is less than 5 mPa · s, sufficient fire-extinguishing power cannot be achieved. This causes inconvenience in practical use.
[0024]
【Example】
Hereinafter, the present invention will be described in detail with reference to examples. Note that the present invention is not limited to these examples.
Synthesis Example 1: Synthesis of polymer A1-1
To a 1 L separable flask, add 120 g of N, N-dimethylacrylamide (DMAA) and 600 g of deionized water, and gradually add a 5% by weight sulfuric acid aqueous solution with stirring to adjust the pH of the solution to 7.30. After the neutralization operation, deionized water was supplemented so that the concentration of the monomer aqueous solution was 15% by weight. And the monomer preparation liquid was put into a 20 degreeC thermostat, nitrogen gas was bubbled stirring with a magnetic stirrer, and it ventilated for 1 hour. Therefore, as a polymerization initiator, 2.740 g of a 5 wt% aqueous solution of VA-044, 3.731 g of a 5 wt% aqueous solution of Rongalite, and 2.182 g of a 5 wt% aqueous solution of tert-butyl hydroperoxide (t-BHPO) were sequentially added. The polymerization reaction was started at 20 ° C. After 5 minutes, stirring and nitrogen gas aeration were stopped, and the polymerization reaction was continued for 16 hours at room temperature in a sealed state. Then, a candy-like polymer A1-1 containing 85% by weight of water was obtained. Further, A1-1 was cut and dissolved in deionized water to prepare 1, 2, and 5 wt% aqueous solutions, respectively.
[0025]
Synthesis Example 2: Synthesis of polymer A1-2
To a 1 L separable flask, add 120 g of N, N-dimethylacrylamide (DMAA) and 600 g of deionized water, and gradually add a 5% by weight sulfuric acid aqueous solution with stirring to adjust the pH of the solution to 7.30. After the neutralization operation, deionized water was supplemented so that the concentration of the monomer aqueous solution was 15% by weight. And the monomer preparation liquid was put into a 0 degreeC thermostat, nitrogen gas was bubbled stirring with a magnetic stirrer, and it ventilated for 1 hour. Therefore, as a polymerization initiator, 2.740 g of a 5 wt% aqueous solution of VA-044, 1.866 g of a 5 wt% aqueous solution of Rongalite, and 1.091 g of a 5 wt% aqueous solution of tert-butyl hydroperoxide (t-BHPO) are sequentially added. The polymerization reaction was started at 20 ° C. After 5 minutes, stirring and nitrogen gas aeration were stopped, and the polymerization reaction was continued for 16 hours at room temperature in a sealed state. Then, a candy-like polymer A1-2 containing 85% by weight of water was obtained. Further, A1-2 was cut and dissolved in deionized water to prepare 1, 2, and 5 wt% aqueous solutions, respectively.
[0026]
Synthesis Example 3: Synthesis of polymer A2-1
To a 1 L separable flask, add 120 g of N-methylacrylamide (NMAA) and 600 g of deionized water, gradually add a 5 wt% aqueous sulfuric acid solution with stirring, and adjust the pH of the solution to 7.30. After performing the summing operation, deionized water was supplemented so that the concentration of the monomer aqueous solution was 15% by weight. The monomer preparation solution was placed in a constant temperature bath at 20 ° C., and nitrogen gas was bubbled while stirring with a magnetic stirrer and aerated for 1 hour. Therefore, 4.559 g of a 5 wt% aqueous solution of VA-044, 4.346 g of a 5 wt% aqueous solution of Rongalite, and 2.542 g of a 5 wt% aqueous solution of t-BHPO were sequentially added, and the polymerization reaction was started at 20 ° C. I let you. After 5 minutes, stirring and nitrogen gas aeration were stopped, and the polymerization reaction was continued for 16 hours at room temperature in a sealed state. Then, a candy-like polymer A2-1 containing 85% by weight of water was obtained. Further, A2-1 was cut and dissolved in deionized water to prepare 1, 2, and 5 wt% aqueous solutions, respectively.
[0027]
Synthesis Example 4: Synthesis of polymer A2-2
To a 1 L separable flask, add 120 g of N-methylacrylamide (NMAA) and 600 g of deionized water, gradually add a 5 wt% aqueous sulfuric acid solution with stirring, and adjust the pH of the solution to 7.30. After performing the summing operation, deionized water was supplemented so that the concentration of the monomer aqueous solution was 15% by weight. The monomer preparation solution was placed in a constant temperature bath at 20 ° C., and nitrogen gas was bubbled while stirring with a magnetic stirrer and aerated for 1 hour. Therefore, 4.559 g of a 5 wt% aqueous solution of VA-044, 2.173 g of a 5 wt% aqueous solution of Rongalite, and 1.271 g of a 5 wt% aqueous solution of t-BHPO were sequentially added, and the polymerization reaction was started at 0 ° C. I let you. After 5 minutes, stirring and nitrogen gas aeration were stopped, and the polymerization reaction was continued for 16 hours at room temperature in a sealed state. Then, a candy-like polymer A2-1 containing 85% by weight of water was obtained. Further, A2-1 was cut and dissolved in deionized water to prepare 1, 2, and 5 wt% aqueous solutions, respectively.
[0028]
Synthesis Example 5: Synthesis of polymer A3
To a 1 L separable flask, 64.57 g of DMAA, 55.43 g of NMAA, and 600 g of deionized water were added, and a neutralization operation was performed in the same manner as in Synthesis Example 2 to prepare a 15 wt% aqueous monomer solution. This was put into a 20 degreeC thermostat, and nitrogen gas was similarly ventilated for 1 hour. Therefore, 4.22 g of a 5 wt% aqueous solution of VA-044, 4.015 g of a 5 wt% aqueous solution of Rongalite, and 2.348 g of a 5 wt% aqueous solution of t-BHPO were sequentially added, and the polymerization reaction was started at 20 ° C. I let you. After 5 minutes, stirring and aeration of nitrogen gas were stopped, and the polymerization reaction was continued for 16 hours at room temperature in a sealed state, to obtain a starchy polymer A3 containing 85% by weight of water. Further, A3 was cut and dissolved in deionized water to prepare 1, 2, and 5 wt% aqueous solutions, respectively.
[0029]
Synthesis Example 6: Synthesis of polymer A4
To a 1 L separable flask, 120 g of DMAA, 0.881 g of acrylic acid (AAc) and 600 g of deionized water were added, and a 5 wt% aqueous potassium hydroxide solution was gradually added with stirring to adjust the pH of the solution to 7.30. After the neutralization operation, deionized water was replenished so that the concentration of the monomer aqueous solution was 15% by weight. The monomer preparation solution was placed in a constant temperature bath at 20 ° C., and nitrogen gas was bubbled while stirring with a magnetic stirrer and aerated for 1 hour. Therefore, 2.767 g of a 5 wt% aqueous solution of VA-044, 5.654 g of a 5 wt% aqueous solution of Rongalite, and 3.306 g of a 5 wt% aqueous solution of t-BHPO were sequentially added, and the polymerization reaction was started at 20 ° C. I let you. After 5 minutes, stirring and aeration of nitrogen gas were stopped, and the polymerization reaction was continued for 16 hours at room temperature in a sealed state. Then, a candy-like polymer A4 containing 85% by weight of water was obtained. Further, A4 was cut and dissolved in deionized water to prepare 1, 2, and 5 wt% aqueous solutions, respectively.
[0030]
Synthesis Example 7: Synthesis of Polymers A5-7
DMAA 120 g, AAc 2.698 g, and 600 g of deionized water were added to a 1 L separable flask, and a neutralization operation was performed in the same manner as in Synthesis Example 6 to prepare three 15% by weight monomer aqueous solutions. Each was placed in a thermostatic bath at 0, 13, and 20 ° C., and nitrogen gas was similarly passed through for 1 hour. Thereafter, 2.824 g of a 5 wt% aqueous solution of VA-044, 3.847 g of a 5 wt% aqueous solution of Rongalite, and 2.249 g of a 5 wt% aqueous solution of t-BHPO were sequentially added to 0, 13, and 20 ° C., respectively. The polymerization reaction was started. After 5 minutes, stirring and aeration of nitrogen gas were stopped, and the polymerization reaction was continued for 16 hours at room temperature in a sealed state. Then, candy-like polymers A5, A6, and A7 containing 85% by weight of water were obtained. Further, A5 to 7 were cut and dissolved in deionized water to prepare 1, 2 and 5 wt% aqueous solutions, respectively.
[0031]
Table 1 summarizes the compositions of Polymers A1 to A7, the polymerization initiation temperature, and the viscosity of a 1 wt% aqueous solution.
[0032]
[Table 1]

[0033]
Examples 1-25, Comparative Examples 1-13
An aqueous solution of a flame retardant such as ammonium dihydrogen phosphate or diammonium hydrogen phosphate was added to the polymer aqueous solution of 1, 2 or 5% by weight obtained in Synthesis Examples 1 to 7 and mixed uniformly to obtain the present invention. An undiluted aqueous fire extinguishing agent was prepared.
In addition, a concentrated water-based fire extinguishing agent that can be used for fire fighting activities while diluting at the time of use was prepared.
Tables 2, 3 and 4 show the composition and physical properties of the water-based fire extinguishing agent of the present invention.
[0034]
[Table 2]

[0035]
[Table 3]

[0036]
[Table 4]

[0037]
As is apparent from the results, (1) the lower critical solution temperature and viscosity of the water-based fire extinguishing agent can be arbitrarily controlled by changing the composition and blending concentration of the polymer and the type and concentration of the anti-extinguishing agent. (2) When the concentration of the fire extinguishing agent exceeded 20% by weight, the solubility of the polymer was remarkably lowered, making it impossible to prepare an aqueous fire extinguishing agent. (3) A water-based fire extinguishing agent can be prepared in a high concentration in advance, and the physical properties of the water-based fire extinguishing agent after dilution are hardly changed, which is convenient for extinguishing a large-scale fire.
[0038]
Comparative Examples 14-19
Table 5 shows the composition of a comparative aqueous fire extinguishing agent for comparison with the aqueous fire extinguishing agent of the present invention.
[0039]
[Table 5]

[0040]
Evaluation Example 1
Using water-based fire extinguishing agents based on the above examples and comparative examples, the water fire extinguisher for residential use is filled, and the internal pressure of the fire extinguisher is 7 kgf / cm using compressed air. ² And an injection test at 25 ° C. was performed to confirm the radiation distance. The results are shown in Table 6.
[0041]
[Table 6]

[0042]
As is clear from Table 6, if the viscosity of the water-based fire extinguishing agent filled in the water fire extinguisher for home use is too high, injection is difficult and the injection distance is shortened. I understand.
[0043]
Evaluation example 2
Using a fire extinguisher filled with 1.5 kg of the water-based fire extinguishing agent of the present invention under the same conditions as in Evaluation Example 1, fire extinguishing tests were conducted for wood fires and tempura oil fires.
The wood fire extinguishing test was conducted based on the ministerial ordinance that establishes the technical standards for fire extinguishers. That is, 35 x 30 x 450 mm cedar air-dried materials are assembled in a 5-girder shape with 5, 5, 4, 5, 5, 4, 4, 4, and so on. Place it on a gantry with a height of 30 cm and a width of 450 x 450 mm, put 0.6 liters of normal heptane as a pre-combustion agent in the combustion pan, burn it for 3 minutes, and then start extinguishing the fire extinguishing status and whether or not reignition after extinguishing A confirmation test was conducted.
The results are shown in Table 7.
[0044]
[Table 7]

[0045]
Evaluation Example 3
Using a fire extinguisher filled with 500 g of the water-based fire extinguishing agent of the present invention under the same conditions as in Evaluation Example 1, a fire extinguishing test for a tempura oil fire was conducted.
Similarly, the tempura oil fire extinguishing test was conducted based on the ministerial ordinance that establishes technical standards for fire extinguishers. That is, 1 liter of soybean oil was put into a wok with a diameter of 300 mm and a depth of 75 mm, and heated and ignited with a gas stove. Fire extinguishing was started when the temperature of the oil reached 400 ° C. Then, the time from immediately after injection to extinguishing was measured as the extinguishing time, and further tests were conducted for the presence or absence of a flame during extinguishing, the presence or absence of re-ignition, and the surface condition of the oil after extinguishing.
The results are shown in Table 8.
In addition, the criteria of fire extinguishing propriety in Table 8 are as follows.
○: Fire extinguishing is possible, ×: Fire extinguishing is not possible (cannot be extinguished even if 500g of the whole amount is injected)
[0046]
[Table 8]

[0047]
As is clear from the above examples and comparative examples, the water-based fire extinguishing agent according to the present invention exhibits excellent fire extinguishing performance against wood fires and tempura oil fires, and efficiently extinguishes with a small amount of extinguishing agent used. Can be carried out.
[0048]
【The invention's effect】
The water-based fire extinguishing agent of the present invention can be thickened or gelled by the heat of the fire, thereby significantly improving the adhesion to the surface of the combustion product and forming a dense film. As a result, the air (oxygen) can be shut off, a continuous fire extinguishing power can be demonstrated, and the re-ignition after fire extinguishing can be sufficiently prevented. We can cope with fire extinguishing surely. Furthermore, according to the present invention, fire extinguishing activities can be carried out even with a small amount of release, and since it has a water loss prevention effect and the pH is near neutral, not only fire extinguishing performance is excellent, but also safety. High water-based fire extinguishing agent can be provided.

Claims

A water-based fire-extinguishing agent obtained by dissolving a thermosensitive polymer exhibiting a lower-limit critical solution temperature in the presence of salt and a flame retardant in water without dissolving it in pure water.

The water-based fire extinguishing agent according to claim 1, wherein the lower critical solution temperature in the presence of salt is 35 to 100 ° C in a mixed aqueous solution of 5 wt% ammonium dihydrogen phosphate and 5 wt% diammonium hydrogen phosphate.

The water-based fire extinguishing agent according to claim 1 or 2, wherein the temperature-sensitive polymer is a homopolymer of a nonionic vinyl monomer or a copolymer of a nonionic vinyl monomer and an ionic vinyl monomer.

The water-based fire extinguishing agent according to any one of claims 1 to 3, wherein the nonionic vinyl monomer is a nonionic acrylamide derivative or a nonionic vinyl alkylamide monomer.

The water-based fire extinguishing agent according to any one of claims 1 to 4, wherein the nonionic acrylamide derivative is at least one selected from N, N-dimethylacrylamide, N-methylacrylamide, and N-acryloylmorpholine. .

The water-based fire extinguishing agent according to any one of claims 1 to 4, wherein the nonionic vinylalkylamide monomer is at least one selected from N-vinylpyrrolidone, N-vinylformamide, and N-vinylacetamide. .

The water-based fire extinguishing agent according to any one of claims 1 to 3, wherein the ionic vinyl monomer is an anionic vinyl monomer.

The water-based fire extinguishing agent according to any one of claims 1 to 7, wherein the flame retardant is at least one compound selected from phosphates, condensed phosphates, sulfates, bicarbonates, and tungstates.

The water-based fire extinguishing agent according to any one of claims 1 to 8, wherein the addition concentration of the extinguishing agent is in the range of 5 to 20% by weight.

The water-based fire extinguishing agent according to any one of claims 1 to 9, wherein the viscosity of a 1% by weight aqueous solution of the temperature-sensitive polymer is 50 to 10,000 Pa · s (25 ° C).

11. In addition to a thermosensitive polymer and an anti-inflammatory agent, one or more of wet penetrants, rust inhibitors, anti-icing agents, colorants, and preservatives are further blended. The water-based fire extinguishing agent described.

The water-based fire-extinguishing agent according to any one of claims 1 to 11, wherein the viscosity of the water-based fire-extinguishing agent is 5 to 5000 mPa · s (25 ° C).

A fire extinguishing method using the water-based fire extinguishing agent according to any one of claims 1 to 12.

The fire extinguishing method according to claim 13, wherein the water-based fire extinguishing agent is adjusted in advance to a viscosity of 5 to 100 mPa · s (25 ° C.), filled in a fire extinguishing device together with a propellant, and ejected to a fire extinguisher.

The fire extinguishing method according to claim 13, wherein the water-based fire extinguishing agent is adjusted in advance to a viscosity of 5 to 100 mPa · s (25 ° C.), and is jetted onto the fire extinguisher by a fire truck or a normal fire fighting apparatus.

The fire-extinguishing method according to claim 13, wherein the water-based fire extinguishing agent is adjusted to a viscosity of 10 to 5000 mPa · s (25 ° C.) in advance and is jetted onto a fire extinguisher by a fire truck or a normal fire fighting apparatus while being diluted during use.