JP3563716B2 - Vacuum insulation material, method of manufacturing vacuum insulation material, refrigerator and refrigerator using vacuum insulation material, notebook computer, electric water heater - Google Patents

Description

【０１２９】
このように構成された真空断熱材は、ヒュームドシリカの凝集粒子を導電性材料である鉄組成物が、その帯電力で解砕、微細化する効果により、ヒュームドシリカ単体の場合より優れた断熱性能を示すのである。実施の形態７における断熱熱性能改善効果は約４６％である。
【０１３０】
以上表１より、導電性粉体添加により、母材であるシリカの凝集粒子が解砕、微細化されており、その結果、熱伝導率改善効果が得られていることが明らかである。
【０１３１】
また、その効果は、粉体比抵抗値が１×１０^８Ω／ｃｍ未満の場合に高く、母材の熱伝導率に対して２５％以上もの改善効果が得られるのである。
【０１３２】
さらに、その効果は、平均１次粒子径が５０ｎｍ以下の乾式シリカの場合、特に顕著であり、実施の形態２と実施の形態３を比較すると、同じ添加剤を使用していながら、母材が平均１次粒子径が５０ｎｍ以下の乾式シリカであるために、その改善効果が２９％から４３％に向上した。
【０１３３】
また、粉体比抵抗値の小さい粉体状カーボンや、金属を含む組成物、金属酸化物を含む組成物などで、非常に良好な断熱性能改善効果が得られていることが分かる。
【０１３４】
（実施の形態８）
実施の形態１と同様の構成の粉体を使用し、攪拌羽根のない混合装置で十分に混合した芯材を１１０℃で１時間乾燥後、被覆材に挿入し、その内部を圧力１３３Ｐａまで減圧した後、開口部をヒートシールにより接着して真空断熱材を作製した。この熱伝導率を測定したところ、実施の形態１と同等の熱伝導率を得るためには、混合に要する時間を約２０％延長する必要があった。
【０１３５】
これは、攪拌羽根がないために混合の効率が低下しているためであると考える。
【０１３６】
（実施の形態９）
図８は、本発明の冷凍冷蔵庫１２の断面図であり、内箱１３と外箱１４とで構成される箱体内部にあらかじめ実施の形態３における真空断熱材１を配設し、前記真空断熱材以外の空間部を硬質ウレタンフォーム１５で発泡充填したことを特徴としている。この場合の冷凍冷蔵庫の全表面積に対して真空断熱材を適用する面積の割合は、６０％である。このように構成された冷凍冷蔵庫は、ヒュームドシリカとカーボンブラックとを均一に分散することにより、導電性材料であるカーボンブラックが、その帯電力でヒュームドシリカの凝集粒子を解砕、微細化する効果により、単位体積あたりの固体接触点が増加するため、その結果、固体熱抵抗が高くなり、固体の熱伝導率が低下するため、ヒュームドシリカ単体の場合より一層優れた断熱性能を有し、かつ、金属蒸着フィルム層を有する被覆材の使用によりヒートリークが抑制されているため、優れた省エネルギー効果を示す。消費電力量を測定したところ、真空断熱材を適用していない際よりも１５％低下しており、断熱効果を確認した。
【０１３７】
（実施の形態１０）
図９は、本発明の冷凍冷蔵庫１２の断面図であり、内箱１３と外箱１４とで構成される箱体内部にあらかじめ実施の形態３における真空断熱材１を配設し、前記真空断熱材以外の空間部を硬質ウレタンフォーム１５で発泡充填したことを特徴としており、冷蔵庫下部に位置する機械室１６にあるコンプレッサー１７近傍と庫内１８との間にも真空断熱材を配設している。この場合の冷凍冷蔵庫の全表面積に対して真空断熱材を適用する面積の割合は、９０％である。このように構成された冷凍冷蔵庫は、ヒュームドシリカとカーボンブラックとを均一に分散することにより、導電性材料であるカーボンブラックが、その帯電力でヒュームドシリカの凝集粒子を解砕、微細化する効果により、単位体積あたりの固体接触点が増加するため、その結果、固体熱抵抗が高くなり、固体の熱伝導率が低下するため、ヒュームドシリカ単体の場合より一層優れた断熱性能を有し、かつ、金属蒸着フィルム層を有する被覆材の使用によりヒートリークが抑制されているため、優れた省エネルギー効果を示す。消費電力量を測定したところ、真空断熱材を適用していない際よりも２５％低下しており、断熱効果を確認した。
【０１３８】
（実施の形態１１）
図１０は、本発明の冷凍冷蔵庫１２の断面図であり、内箱１３と外箱１４とで構成される箱体内部にあらかじめ実施の形態３における真空断熱材１を配設し、前記真空断熱材以外の空間部を硬質ウレタンフォーム１５で発泡充填したことを特徴としており、冷蔵庫下部に位置する機械室１６にあるコンプレッサー１７近傍と庫内１８との間にも真空断熱材を配設している。この場合の冷凍冷蔵庫の全表面積に対して真空断熱材を適用する面積の割合は、９０％である。また、真空断熱材と内箱、および、真空断熱材と外箱のいずれの空間にもウレタンフォームが充填されているために、冷凍冷蔵庫の外観の平面性が改善された。このように構成された冷凍冷蔵庫は、ヒュームドシリカとカーボンブラックとを均一に分散することにより、導電性材料であるカーボンブラックが、その帯電力でヒュームドシリカの凝集粒子を解砕、微細化する効果により、単位体積あたりの固体接触点が増加するため、その結果、固体熱抵抗が高くなり、固体の熱伝導率が低下するため、ヒュームドシリカ単体の場合より一層優れた断熱性能を有し、かつ、金属蒸着フィルム層を有する被覆材の使用によりヒートリークが抑制されているため、優れた省エネルギー効果を示す。消費電力量を測定したところ、真空断熱材を適用していない際よりも２５％低下しており、断熱効果を確認した。
【０１３９】
（実施の形態１２）
図１１は、本発明のノート型コンピュータ１９の断面図であり、装置内部のメインボード２０上の発熱部２１と装置ケース２２底部との間を遮断する、実施の形態５における真空断熱材１と、放熱板２３とを具備し、真空断熱材１が装置ケース２２底部に密着していることを特徴とする。このように構成されたノート型コンピュータは、ヒュームドシリカとカーボンブラックとを均一に分散することにより、導電性材料であるカーボンブラックが、その帯電力でヒュームドシリカの凝集粒子を解砕、微細化する効果により、単位体積あたりの固体接触点が増加するため、その結果、固体熱抵抗が高くなり、固体の熱伝導率が低下するため、ヒュームドシリカ単体の場合より一層優れた断熱性能を有し、かつ、金属蒸着フィルム層を有する被覆材の使用によりヒートリークをも抑制された真空断熱材が、底面への熱伝達を効果的に遮断するために、装置ケース底部と密着されているために、高度に断熱されており、装置表面の温度上昇を抑え利用者に不快感を与えることがない。
【０１４０】
ノート型コンピュータ底面の温度を測定したところ、真空断熱材を適用していない際よりも６℃低下しており、断熱効果を確認した。
【０１４１】
（実施の形態１３）
図１２は、本発明のノート型コンピュータ１９の断面図であり、装置内部のメインボード２０上の発熱部２１と装置ケース２２底部との間を遮断する、実施の形態５における真空断熱材１と、放熱板２３とを具備し、真空断熱材１の被覆面積が、発熱部２１面積より大きいことを特徴とする。このように構成されたノート型コンピュータは、ヒュームドシリカとカーボンブラックとを均一に分散することにより、導電性材料であるカーボンブラックが、その帯電力でヒュームドシリカの凝集粒子を解砕、微細化する効果により、単位体積あたりの固体接触点が増加するため、その結果、固体熱抵抗が高くなり、固体の熱伝導率が低下するため、ヒュームドシリカ単体の場合より一層優れた断熱性能を有し、かつ、金属蒸着フィルム層を有する被覆材の使用によりヒートリークをも抑制された真空断熱材が、底面への熱伝達を効果的に遮断するために、発熱部面積より広い面積にて適用されているために、真空断熱材端部からの熱の回り込みによる熱伝達を防ぎ、底面への熱伝達を効果的に遮断しているため、装置表面の温度上昇を抑え利用者に不快感を与えることがない。底面の温度を測定したところ、真空断熱材を適用していない際よりも７℃低下しており、断熱効果を確認した。
【０１４２】
（実施の形態１４）
図１３は、本発明の電気湯沸かし器２４の断面図であり、外容器２５と、貯水用容器２６と、蓋体２７と、貯水用容器の水を加熱するヒーター２８と、貯水用容器外周の実施の形態５における真空断熱材１とから構成されることを特徴としている。また、貯水用容器の下部に取り付けられたヒーターの近傍付近まで、真空断熱材を取り付けている。このように構成された電気湯沸かし器は、ヒュームドシリカとカーボンブラックとを均一に分散することにより、導電性材料であるカーボンブラックが、その帯電力でヒュームドシリカの凝集粒子を解砕、微細化する効果により、単位体積あたりの固体接触点が増加するため、その結果、固体熱抵抗が高くなり、固体の熱伝導率が低下するため、ヒュームドシリカ単体の場合より一層優れた断熱性能を有し、かつ、金属蒸着フィルム層を有する被覆材の使用によりヒートリークが抑制された真空断熱材を適用しているため、優れた省エネルギー効果を示す。消費電力量を測定したところ、真空断熱材を適用していない際よりも１０％低下しており、断熱効果を確認した。
【０１４３】
（実施の形態１５）
図１４は、本発明の電気湯沸かし器２４の断面図であり、外容器２５と、貯水用容器２６と、蓋体２７と、貯水用容器の水を加熱するヒーター２８と、貯水用容器外周、および、蓋体部の実施の形態５における真空断熱材１とから構成されることを特徴としている。また、貯水用容器の下部に取り付けられたヒーターの近傍付近まで、真空断熱材を取り付けている。このように構成された電気湯沸かし器は、ヒュームドシリカとカーボンブラックとを均一に分散することにより、導電性材料であるカーボンブラックが、その帯電力でヒュームドシリカの凝集粒子を解砕、微細化する効果により、単位体積あたりの固体接触点が増加するため、その結果、固体熱抵抗が高くなり、固体の熱伝導率が低下するため、ヒュームドシリカ単体の場合より一層優れた断熱性能を有し、かつ、金属蒸着フィルム層を有する被覆材の使用によりヒートリークが抑制された真空断熱材を適用しているため、優れた省エネルギー効果を示す。消費電力量を測定したところ、真空断熱材を適用していない際よりも１２％低下しており、断熱効果を確認した。
【０１４４】
（実施の形態１６）
図１５は、本発明の真空断熱材の製造方法における、攪拌羽根２９を有する混合容器３０であり、粉体均一分散ステップにおいて、攪拌羽根を有する混合容器を使用するために、原料中に存在するヒュームドシリカの二次、あるいは、三次凝集体を解砕できる。その結果、ヒュームドシリカと粉体状カーボン材料は、均一に分散可能となるため、部分的な分散度の低下による断熱性能の悪化を抑制できる。
【０１４５】
本発明の真空断熱材は、芯材と被覆材とからなり、減圧下で芯材を被覆材に封入したものである。また、合成ゼオライト，活性炭，活性アルミナ，シリカゲル，ドーソナイト，ハイドロタルサイトなどの物理吸着剤、および、アルカリ金属やアルカリ土類金属の酸化物および水酸化物などの化学吸着剤などの、水分吸着剤やガス吸着剤を使用してもよい。また、粉体である芯材を不織布にて封止したあと、さらに被覆材に封止してもよい。また、真空封止前に、芯材の乾燥工程を加えてもよい。また、粉体をバインダーや加圧により固形化して使用してもよい。
【０１４６】
また、本発明の冷凍冷蔵庫および冷凍機器は、これらの動作温度帯である−３０℃から常温、また自動販売機などの、より高温までの範囲で温冷熱を利用した機器を指す。また、電気機器に限ったものではなく、ガス機器なども含むものである。
【０１４７】
また、本発明のノート型コンピュータは、動作温度帯である常温から８０℃付近までの範囲で断熱を必要とする機器の代表として記したものであり、特にこれに限ったものではない。例えば、液晶パネルを有するカーナビゲーションシステムの液晶部分とＣＰＵによる発熱部分の断熱にも利用可能である。
【０１４８】
また本発明の電気湯沸かし器は、動作温度帯である常温から１００℃付近までの範囲で断熱を必要とする機器の代表として記したものであり、例えば、炊飯器，食器乾燥器などにも同様に利用できるものである。また、電気機器に限ったものではなく、ガス機器なども含むものである。
【０１４９】
本発明の導電性粉体は、導電性を有する粉体であればいかなる粉体でも利用できる。およその目安としては、粉体比抵抗値が１×１０^１３ｃｍ／Ω以下のものである。無機粉体であれば、例えば、金属粉体，金属酸化物粉体，炭酸化物粉体，塩化物粉体，粉体状カーボンなど、また有機粉体であれば、金属ドープ粉体などである。粉体比抵抗値が、１×１０^８ｃｍ／Ω以下であれば、より好ましい。さらに高断熱性能を求める場合は、１０ｃｍ／Ω以下が望ましい。また、母材と均一混合することを考慮すると、粉体径は細かい方が好ましいといえる。
【０１５０】
また、導電性粉体の添加量は１ｗｔ％以上であれば効果が得られる。添加する粉体種により最適添加量は異なるが、添加量の増加と共に断熱性能向上効果が大きくなる傾向が見られる。しかしながら、４０％以上添加しても、その効果は飽和に達することが多い。よって、最適添加量は、３％から３０％程度であるといえる。
【０１５１】
本発明のシリカは、酸化珪素化合物のことを指しており、湿式シリカ，乾式シリカ，エアロゲルなどが利用できる。また、主成分がシリカであって、他の成分が含まれている粉体をも含むものである。
【０１５２】
本発明の乾式シリカは、アーク法により製造されたケイ酸、熱分解により製造されたケイ酸などの乾式により製造された種々の粒径を有する酸化珪素化合物が使用可能である。これら乾式シリカは、凝集粒子間の静電力が比較的弱く、導電性粉体を添加した際の凝集解砕効果が高い。また、断熱性能が優れていることから一次粒子径が５０ｎｍ以下のものが好ましく、特に高断熱性能を必要とする場合には、一次粒子径が１０ｎｍ以下が望ましい。また、種々の粒径の乾式ドシリカの混合物も利用可能である。例えば、粒径を規定した量産品Ａと量産品Ｂの生産切り替えの際に生成する粒径がＡからＢの間で抑制されていない正規ロット外品であっても利用することが可能であり、より低コストで真空断熱材を製造することが可能である。
【０１５３】
本発明の粉体状カーボン材料は、カーボンブラック，黒鉛化炭素粉末，活性炭，アセチレンブラックなど、粉体状のカーボン材料であれば使用可能である。汎用性があり安価であることから、カーボンブラックの使用が簡便であるが、カーボンブラックを用いる際には経時的なガス発生を抑制し、長期間にわたって優れた断熱性能を維持するため、比表面積１００ｍ^２／ｇ未満が好ましい。また、同様の理由により、黒鉛化炭素粉末の利用も好ましい。
【０１５４】
本発明の金属を含む組成物は、組成として金属を含み、導電性を有する粉体であれば、適用可能である。例えば、鉄，銅，金，白金などが適用可能である。主成分としてこれらを含み、他の物質が存在していてもよい。
【０１５５】
本発明の金属酸化物を含む組成物は、組成として金属酸化物を含み、導電性を有する粉体であれば、適用可能である。例えば、酸化チタン，酸化亜鉛，酸化錫などである。主成分としてこれらを含み、他の物質が存在していてもよい。
【０１５６】
本発明の被覆材は、芯材と外気とを遮断することが可能なものが利用できる。例えば、ステンレススチール，アルミニウム，鉄などの金属薄板や、金属薄板とプラスチックフィルムとのラミネート材などである。ラミネート材は、表面保護層，ガスバリア層、および熱溶着層によって構成されることが好ましい。表面保護層としては、ポリエチレンテレフタレートフィルム，ポリプロピレンフィルムの延伸加工品などが利用でき、さらに、外側にナイロンフィルムなどを設けると可とう性が向上し、耐折り曲げ性などが向上する。ガスバリア層としては、アルミなどの金属箔フィルムや金属蒸着フィルムが利用可能であるが、よりヒートリークを抑制し、優れた断熱効果を発揮するには金属蒸着フィルムが好ましい。ポリエチレンテレフタレートフィルム，エチレン・ビニルアルコール共重合体樹脂フィルム，ポリエチレンナフタレートフィリムなどへの蒸着が好ましい。また、熱溶着層としては、低密度ポリエチレンフィルム，高密度ポリエチレンフィルム，ポリプロピレンフィルム，ポリアクリロニトリルフィルム，無延伸ポリエチレンテレフタレートフィルムなどが使用可能である。
【０１５７】
本発明の真空断熱材の製造方法における攪拌羽根を有する混合容器は、原料中に存在するシリカの二次、あるいは、三次凝集体を解砕できる攪拌羽根を有しているものであれば、使用することができる。混合容器は、円筒状・球・立方体であっても、特に形状を問わず適用することが可能である。また、混合容器は、攪拌羽根を用いた混合に加え、さらに、自ら回転、または、底部ローターにより、粉体を回転混合することが可能なものも使用でき、より混合分散に要する時間が短縮される。
【０１５８】
次に本発明に対する比較例を示す。
【０１５９】
（比較例１）
真空断熱材の芯材には、母材として平均粒径７．２μｍのパーライト粉末９５ｗｔ％と、添加剤として粉体比抵抗値が０．６Ω／ｃｍのカーボンブラック５ｗｔ％とを攪拌羽根を有する混合容器内で均一混合させたものを用いた。芯材を金属箔層と熱可塑性ポリマー層とを有する被覆材に充填し、圧力１３３Ｐａにて熱融着装置にて封止し、真空断熱材とした。
【０１６０】
この真空断熱材の熱伝導率を測定したところ、０．００７２ｋｃａｌ／ｍｈ℃であった。パーライト粉末単独で真空断熱材としたときの熱伝導率は、０．００６５ｋｃａｌ／ｍｈ℃であり、カーボンブラックをパーライト粉末に５ｗｔ％添加することにより、断熱性能の悪化を確認した。
【０１６１】
カーボンブラックを同様に真空断熱材として評価した場合の熱伝導率は０．０２２０ｋｃａｌ／ｍｈ℃であることから、パーライトとカーボンブラックとがブレンド比どおりの熱伝導率を発現させているものと考える。
【０１６２】
よって、母材であるパーライトが電気的な帯電によっても解砕されない粒子構造であるため、導電性材料を添加しても熱伝導率改善効果が得られていないものと考える。このことからも、カーボンブラックの添加による熱伝導率改善効果は、輻射熱伝導の改善によるものではないことが裏付けされたと考える。
【０１６３】
（比較例２）
真空断熱材の芯材には、母材として平均１次粒子径が７ｎｍであるヒュームドシリカ９５ｗｔ％と、添加剤として導電性粉体ではない、粉体比抵抗値１×１０^１６Ω／ｃｍである酸化アルミニウム組成物５ｗｔ％とを攪拌羽根を有する混合容器内で均一混合させたものを用いた。芯材を金属箔層と熱可塑性ポリマー層とを有する被覆材に充填し、圧力１３３Ｐａにて熱融着装置にて封止し、真空断熱材とした。
【０１６４】
この真空断熱材の熱伝導率を測定したところ、０．００５３ｋｃａｌ／ｍｈ℃であった。ヒュームドシリカ単独で真空断熱材としたときの熱伝送率は、０．００５５ｋｃａｌ／ｍｈ℃であり、酸化アルミニウム組成物をヒュームドシリカに５ｗｔ％添加することにより、断熱性能の改善は確認できなかった。
【０１６５】
これは、酸化アルミニウム組成物がほとんど導電性を示さないために、ヒュームドシリカの凝集粒子を解砕、微細化する効果がなく、その結果断熱性能に影響を及ぼさないものと考える。本比較で用いた酸化アルミニウム組成物単体での熱伝導率は０．００７５ｋｃａｌ／ｍｈ℃であった。
【０１６６】
【発明の効果】
以上のように本発明によれば、母材に添加材を加えた場合に発現する断熱性能改善要因を明確化したために、その理論に準じて適切な母材と添加材を選択することにより、粉体未添加の場合と比較して２０％以上の断熱性能の改善が得られる非常に高性能な真空断熱材、および、真空断熱材の製造方法を提供することができる。また、高性能な真空断熱材を具備することにより、省エネルギーに貢献できる機器を提供することができる。また、高性能な真空断熱材を具備することにより、装置内部の熱が表面に伝達することにより利用者に不快感を与えることのない機器を提供することができる。
【図面の簡単な説明】
【図１】本発明の一実施例である真空断熱材の断面図
【図２】本発明の一実施例である真空断熱材の断面図
【図３】本発明の一実施例である真空断熱材の断面図
【図４】本発明の一実施例である真空断熱材の断面図
【図５】本発明の一実施例である真空断熱材の断面図
【図６】本発明の一実施例である真空断熱材の断面図
【図７】本発明の一実施例である真空断熱材の断面図
【図８】本発明の一実施例である冷凍冷蔵庫の断面図
【図９】本発明の一実施例である冷凍冷蔵庫の断面図
【図１０】本発明の一実施例である冷凍冷蔵庫の断面図
【図１１】本発明の一実施例であるノート型コンピュータの断面図
【図１２】本発明の一実施例であるノート型コンピュータの断面図
【図１３】本発明の一実施例である電気湯沸かし器の断面図
【図１４】本発明の一実施例である電気湯沸かし器の断面図
【図１５】本発明の一実施例である混合容器の一部断面図
【図１６】粉体状カーボン添加シリカ、および、シリカ単体、理想黒体（５０℃）の放射エネルギー分布を示す特性図
【図１７】添加剤の粉体比抵抗値と真空断熱材の熱伝導率の関係を示す特性図
【符号の説明】
１ 真空断熱材
２ 被覆材
３ 湿式シリカ
４ 粉体状カーボン材料
５ 乾式シリカ
６ カーボンブラック
７ ヒュームドシリカ
８ 酸化錫組成物
９ 酸化チタン組成物
１０ 炭酸カルシウム組成物
１１ 鉄組成物
１２ 冷凍冷蔵庫
１３ 内箱
１４ 外箱
１５ 硬質ウレタンフォーム
１６ 機械室
１７ コンプレッサー
１８ 庫内
１９ ノート型コンピュータ
２０ メインボード
２１ 発熱部
２２ 装置ケース
２３ 放熱板
２４ 電気湯沸かし器
２５ 外容器
２６ 貯水用容器
２７ 蓋体
２８ ヒーター
２９ 攪拌羽根
３０ 混合容器[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a vacuum heat insulating material and a device to which the vacuum heat insulating material is applied.
[0002]
[Prior art]
In recent years, energy saving has been demanded because of the importance of preventing global warming, which is a global environmental problem, and energy saving has been promoted for consumer appliances. In particular, with respect to equipment and houses utilizing hot and cold heat, a heat insulating material having excellent heat insulating properties is required from the viewpoint of efficiently using heat.
[0003]
In addition, as a device other than the cold / hot heat utilizing device, in a notebook computer, when the heat generated inside the device is transmitted to the surface of the device case and the temperature of the device case surface rises, the body of the device user and the device There is a problem that heat in a portion that comes into contact with the case surface for a long period of time gives an unpleasant feeling to a user of the apparatus, and a heat insulating material having excellent heat insulating properties is also required here.
[0004]
As a general heat insulating material, a fibrous body such as glass wool or a foamed body such as urethane foam is used. However, in order to improve the heat insulating properties of these heat insulating materials, it is necessary to increase the thickness of the heat insulating material, and when there is a limit to the space in which the heat insulating material can be filled and space saving or effective use of the space is required. Cannot be applied.
[0005]
As one means for solving such a problem, there is a vacuum heat insulating material composed of a core material for holding a space and a jacket material for shutting off the space and the outside air. In general, powder materials, fiber materials, interconnected foams, and the like are used as the core material. In recent years, however, there has been a wide variety of demands for vacuum heat insulating materials, and vacuum materials with higher performance than in the past have been used. Insulation is needed.
[0006]
Therefore, for the purpose of improving the performance of the core material, Japanese Patent Application Publication No. Sho 60-33479 proposes a vacuum heat insulating material characterized in that powdered carbon is uniformly dispersed in pearlite powder. In addition, a vacuum heat insulating material characterized in that the powdered carbon is carbon black has been proposed. By uniformly dispersing carbon black in pearlite, the heat insulating performance can be improved by 20% under optimum conditions. Has been proposed.
[0007]
Further, Japanese Patent Laid-Open Publication No. 61-36595 proposes a vacuum heat insulating material characterized in that carbon powder is uniformly dispersed in various powders. The example proposes that by uniformly dispersing carbon black in silica having a single particle diameter of 100 nm, the heat insulation performance is improved by 20% under optimum conditions.
[0008]
Further, Japanese Patent Publication No. Hei 8-20032 proposes a vacuum heat insulating material using fine powder generated from fume generated in ferrosilicon production. Further, a vacuum heat insulating material characterized in that the fine powder contains at least 1 wt% of carbon has been proposed. This proposal shows a 23% improvement in thermal insulation performance.
[0009]
It is believed that these improvements in heat insulation performance are due to the effect of reducing radiant heat conduction due to the added carbon powder and the like.
[0010]
[Problems to be solved by the invention]
However, pearlite in Japanese Patent Publication No. 60-33479, silica having a single particle diameter of 100 nm in Japanese Patent Application Laid-Open No. 61-36595, and fume generated in ferrosilicon production in Japanese Patent Publication No. Hei 8-20032 are used as base materials. In the specification that contains physical carbon or carbon as an additive, the heat insulating performance improvement effect was improved compared to the case where no additive was added, but the effect was about 20%, which is a leap compared to the conventional vacuum heat insulating material. Thermal insulation performance is not good.
[0011]
On the other hand, our analysis results show that the addition of additives such as carbon powder to the matrix silica does not significantly affect the emission of thermal energy in the normal temperature range, that is, the thermal conduction of radiation. It became. FIG. 16 shows measurement results of radiant energy distributions of silica alone, silica to which powdered carbon is added, and an ideal black body (50 ° C.).
[0012]
From FIG. 16, in the vacuum heat insulating material used in the temperature range from room temperature to around 100 ° C., the change in the amount of radiant energy due to the addition of powdered carbon is very small, and the reduction in radiant heat conduction is considered to be a factor in reducing the thermal conductivity. Judge that you can not. The same applies to the analysis results of additives other than powdered carbon, which are said to be effective in reducing radiant heat conduction, such as titanium oxide.
[0013]
Therefore, in order to further improve the heat insulation performance, it is important to clarify the heat insulation performance improvement effect factors due to the addition of the additives and to select a more suitable material.
[0014]
Therefore, the purpose of the present invention is to clarify the heat-insulating performance improvement factors that appear when an additive is added to a base material, and then select an appropriate base material and an additive, and compare the results with those without powder addition. Another object of the present invention is to provide a very high-performance vacuum heat insulating material capable of improving heat insulating performance by 20% or more, and a method of manufacturing the vacuum heat insulating material. Another object of the present invention is to provide a device that can contribute to energy saving by providing a high-performance vacuum heat insulating material. Another object of the present invention is to provide a device which does not cause a user to feel uncomfortable by transmitting heat inside the device to the surface by providing a high-performance vacuum heat insulating material.
[0015]
[Means for Solving the Problems]
In view of the above problems, the vacuum heat insulating material of the present invention is characterized by having a coating material having silica as a core material containing at least 1 wt% or more of an additive for breaking up aggregated silica particles.
[0016]
We performed an analysis focusing on thermal conductivity and powder property change by adding various additives to silica as a base material. As a result, it has been found that whenever the thermal conductivity reducing effect is obtained, the aggregated silica particles are crushed and the secondary particle diameter is reduced. For example, in one example verified using fumed silica, which is a kind of dry silica, and carbon black, which has been found to have an effect of breaking up aggregated particles of silica, the actually measured average value of the aggregated particle diameter is 2.4 μm. By adding 5% of Toka Black # 8500F to certain Aerosil 380 (manufactured by Nippon Aerosil), the aggregated particle diameter was reduced to 1.0 μm. In this case, the heat insulation performance was improved by about 40% by the addition of carbon black.
[0017]
In addition, silica is specified as a base material because the aggregated particle diameter of the silica is a powder in which the silica forms an aggregate by an intermolecular interaction, and has a property that the aggregated particles are broken by applying a stress. Because it is a thing. At present, only silica has been confirmed as having such characteristics. Further, since it is a fine powder, it can be bent and molded flexibly as a vacuum heat insulating material.
[0018]
From the above, the effect of improving the heat insulation performance exhibited by the addition of the additive is not due to the reduction in radiant heat conduction, but is reduced by agglomeration of the aggregated particles, thereby increasing the solid contact points per unit volume. As a result, it is considered that the thermal resistance of the solid increases and the thermal conductivity of the solid decreases.
[0019]
It was also confirmed that the combination of these improved the internal pressure dependency of the thermal conductivity of the vacuum heat insulating material. This is thought to be due to the fact that the diameter of the voids formed between the aggregated particles is reduced due to the effect of crushing and reducing the aggregated particle diameter, thereby reducing the gas thermal conductivity. Therefore, the reliability of the heat insulating performance over time of the vacuum heat insulating material is improved.
[0020]
It was also confirmed that the temperature dependency of the heat insulation performance was improved. This is thought to be because the increase in the thermal conductivity of the gas due to the increase in the momentum of the gas molecules due to the temperature rise is suppressed by the effect of making the void diameter finer.
[0021]
The vacuum heat insulating material of the present invention is characterized in that the additive is a conductive powder.
[0022]
We have found that when the additive is a conductive powder, the aggregated silica particles are crushed and the secondary particle diameter is reduced. For example, in an example verified using fumed silica, which is a kind of dry silica, and carbon black, which is a conductive powder, Aerosil 380 (manufactured by Nippon Aerosil), whose measured average value of the aggregated particle diameter is 2.4 μm, By adding 5% of Toka Black # 8500F, the aggregated particle diameter was reduced to 1.0 μm. In this case, the heat insulation performance was improved by about 40% by the addition of carbon black.
[0023]
Probably, it is considered that the aggregation of the silica powder is broken by the electric charge of the conductive powder giving an electric repulsion to the cohesion of the silica powder. It is considered that the agglomeration is refined by disintegration and the solid contact points per unit volume increase, so that the solid thermal resistance increases and the thermal conductivity of the solid decreases.
[0024]
Therefore, it can be said that the combination of the powders exhibiting the heat insulating performance improving effect is silica, which forms agglomeration by electrostatic force, as the base material, and conductive powder as the additive. Only in this case, the effect of improving the heat insulating performance can be obtained.
[0025]
It was confirmed that the heat insulation performance was greatly improved by the above configuration without reducing the radiant heat conduction. Therefore, the effect of improving the heat insulating performance that is exhibited when the additive is added to the base material is due to the decrease in the aggregated particle diameter due to the addition of the conductive powder.
[0026]
Further, the vacuum heat insulating material of the present invention has a powder specific resistance of 1 × 10 ⁸ Less than Ω / cm.
[0027]
Further, there is a substantially linear relationship between the specific resistance of the powder, which is a measure of the conductivity of the powder, and the effect of improving the heat insulating performance. ⁸ It was confirmed that particularly excellent heat insulating performance was exhibited when the resistance was less than Ω / cm. FIG. 17 shows the thermal conductivity values when 5% of powder having various powder resistivity values are added to fumed silica.
[0028]
FIG. 17 shows that the thermal conductivity tends to decrease as the powder specific resistance decreases. This factor is considered to be due to the fact that the powder conductivity increases as the powder resistivity decreases, and the crushing effect on the aggregated particles of silker increases.
[0029]
Further, the vacuum heat insulating material of the present invention is characterized in that the silica is dry silica having an average primary particle diameter of 50 nm or less.
[0030]
It was confirmed that the dry silica was more easily disintegrated than the wet silica by the addition of the conductive powder. This is probably because the interaction with hydrogen bonds between particles is small because the surface silanol groups are small as compared with wet silica. Therefore, the effect of improving the heat insulation performance is greater.
[0031]
Further, when the average primary particle diameter is 50 nm or less, the number of fixed contact points per unit volume increases and the number of solid contact points increases, so that the heat resistance of the solid increases and the heat conduction of the solid decreases. Due to the effect of miniaturization and a decrease in gas thermal conductivity, the heat insulation performance is particularly excellent.
[0032]
In addition, the diameter of the voids formed between the aggregated particles is reduced due to the effect of crushing and reducing the aggregated particle diameter, so that the gas thermal conductivity is reduced, and the reliability of the thermal insulation performance of the vacuum insulation over time is reduced. The properties are also dramatically improved.
[0033]
Further, the vacuum heat insulating material of the present invention is characterized in that the conductive powder is powdered carbon.
[0034]
When the conductive powder is powdered carbon, the powder has a small specific resistance value of 0.1 Ω / cm, and the powder having a large specific resistance is as small as about 5 and has an excellent heat insulating performance improving effect. Also, it is very useful because an inexpensive one can be selected industrially.
[0035]
The vacuum heat insulating material of the present invention is characterized in that the conductive powder has a composition containing a metal.
[0036]
When the conductive powder has a composition containing a metal, a powder having a small specific resistance value is as small as 0.001 Ω / cm, which is excellent in the heat insulating performance improving effect. Further, since gas is hardly generated in the vacuum heat insulating material over time, the reliability over time is excellent.
[0037]
The vacuum heat insulating material of the present invention is characterized in that the conductive powder has a composition containing a metal oxide.
[0038]
When the conductive powder has a composition containing a metal oxide, a powder having a small specific resistance value is as small as about 1.0 Ω / cm, which is excellent in the heat insulating performance improving effect. Further, since gas is hardly generated in the vacuum heat insulating material over time, the reliability over time is excellent.
[0039]
With the above configuration, after clarifying the factors of the heat insulating performance improvement effect that appears when the additive is added to the base material, select the appropriate base material and additive, and compare with the case without powder addition As a result, it is possible to provide a very high-performance vacuum heat insulating material capable of improving the heat insulating performance by 20% or more.
[0040]
In the method for producing a vacuum heat insulating material of the present invention, at least 1 wt% of an additive having an effect of crushing aggregated particles of silica by being added is added to a mixing vessel having stirring blades, and silica is added. A step of uniformly dispersing the powder by mixing with a stirring blade, and a step of vacuum-sealing the core material to a coating material under reduced pressure using the powder as a core material.
[0041]
By using a mixing vessel with stirring blades, thoroughly mix and uniformly disperse the conductive powder and silica, effectively disintegrate the silica by charging the conductive powder, and achieve excellent heat insulation performance. The developed core material can be adjusted.
[0042]
Moreover, the manufacturing method of the vacuum heat insulating material of the present invention is characterized in that the additive is a conductive powder.
[0043]
In the method for producing a vacuum heat insulating material of the present invention, the powder specific resistance of the conductive powder is 1 × 10 ⁸ Less than Ω / cm.
[0044]
The method for producing a vacuum heat insulating material of the present invention is characterized in that the silica is dry silica having an average primary particle diameter of 50 nm or less.
[0045]
The method for producing a vacuum heat insulating material of the present invention is characterized in that the conductive powder is powdered carbon.
[0046]
The method for producing a vacuum heat insulating material of the present invention is characterized in that the conductive powder has a composition containing a metal.
[0047]
Further, the method for producing a vacuum heat insulating material of the present invention is characterized in that the conductive powder has a composition containing a metal oxide.
[0048]
With the above configuration, after clarifying the factors of the heat insulation performance improving effect that is exhibited when the additive is added to the base material, by selecting an appropriate base material and the additive, and further uniformly dispersing these. It is possible to provide a method of manufacturing a very high-performance vacuum heat insulating material that can improve the heat insulating performance by 20% or more as compared with the case where no powder is added.
[0049]
A refrigerator and a refrigerator according to the present invention provide a coating material comprising silica as a core material containing at least 1 wt% of an additive having an effect of disintegrating silica aggregate particles by being added between an inner box and an outer box. A refrigerator comprising a heat-insulating box provided with a vacuum heat-insulating material, wherein the ratio of the area to which the vacuum heat-insulating material is applied to the entire surface area of the refrigerator is 3% or more and 90% or less. Is what you do.
[0050]
Further, the refrigerator and the refrigerator of the present invention are characterized by comprising a vacuum heat insulating material whose additive is a conductive powder.
[0051]
In addition, the refrigerator and the refrigerator of the present invention have a powder specific resistance of 1 × 10 ⁸ A vacuum heat insulating material having a resistance of less than Ω / cm is provided.
[0052]
Further, the refrigerator and the refrigerator of the present invention are characterized in that the silica comprises a vacuum heat insulating material that is dry silica having an average primary particle diameter of 50 nm or less.
[0053]
Further, the refrigerator and the refrigerator of the present invention are characterized in that the conductive powder is provided with a vacuum heat insulating material that is powdered carbon.
[0054]
A refrigerator and a refrigerator according to the present invention are characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal.
[0055]
The refrigerator and refrigerator of the present invention are characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal oxide.
[0056]
With the above configuration, after clarifying the factors of the heat insulating performance improvement effect that appears when the additive is added to the base material, select the appropriate base material and additive, and compare with the case without powder addition By providing a very high-performance vacuum heat insulating material that can improve the heat insulating performance by 20% or more, it is possible to provide a refrigerator and a refrigerator that can contribute to energy saving.
[0057]
In addition, since the vacuum heat insulating material having the above-described structure is used, an effective energy saving effect can be obtained when the ratio of the area to which the vacuum heat insulating material is applied to the entire surface area of the refrigerator is 3% or more and 90% or less. Can be.
[0058]
In the case of the vacuum heat insulating material having the conventional heat insulating performance, the effect is hardly exhibited when the ratio of the applied area is small, but in the present configuration, the effect is recognized from 3% or more. If the ratio of the applied area is less than 3%, the energy saving effect is reduced to an error range. In addition, if the technical level of the conventional vacuum insulation material is high, the internal pressure dependence of the insulation performance is large. I will. However, since the vacuum heat insulating material of this configuration has the property that the pressure dependency of the heat insulating performance is very small, application up to 90% is possible, and a very high energy saving effect can be obtained. In addition, it is considered that application of 90% or more is difficult due to the structure of the refrigerator.
[0059]
A refrigerator and a refrigerator according to the present invention provide a coating material comprising silica as a core material containing at least 1 wt% of an additive having an effect of disintegrating silica aggregate particles by being added between an inner box and an outer box. A refrigerator comprising a heat-insulating box provided with a vacuum heat-insulating material, comprising a machine room provided with a compressor below the heat-insulating box, wherein the heat-insulating material comprises a machine room and an inner box. It is characterized by being arranged in between.
[0060]
Further, the refrigerator and the refrigerator of the present invention are characterized by comprising a vacuum heat insulating material whose additive is a conductive powder.
[0061]
In addition, the refrigerator and the refrigerator of the present invention have a powder specific resistance of 1 × 10 ⁸ A vacuum heat insulating material having a resistance of less than Ω / cm is provided.
[0062]
Further, the refrigerator and the refrigerator of the present invention are characterized in that the silica comprises a vacuum heat insulating material that is dry silica having an average primary particle diameter of 50 nm or less.
[0063]
Further, the refrigerator and the refrigerator of the present invention are characterized in that the conductive powder is provided with a vacuum heat insulating material that is powdered carbon.
[0064]
A refrigerator and a refrigerator according to the present invention are characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal.
[0065]
The refrigerator and refrigerator of the present invention are characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal oxide.
[0066]
With the above configuration, after clarifying the factors of the heat insulating performance improvement effect that appears when the additive is added to the base material, select the appropriate base material and additive, and compare with the case without powder addition By providing a very high-performance vacuum heat-insulating material capable of improving the heat-insulating performance by 20% or more at the site where the temperature difference is the largest between the machine room and the inner box, and where the heat-insulating effect is high, It is possible to provide refrigerators and refrigerators that can effectively contribute to energy savings, and because the application site of the vacuum insulation material does not affect the appearance of the heat insulation box, the exterior of the refrigerator must be considered. Therefore, there is no need to particularly consider the surface smoothness of the vacuum heat insulating material.
[0067]
Further, because of the vacuum heat insulating material having the above-described structure, even if it is disposed between the machine room and the inner box where the temperature difference is the largest due to the structure of the refrigerator, the temperature dependency of the heat insulating performance is small, and the heat insulation over time is possible. Since the deterioration of the performance is extremely small, it is possible to provide a refrigerator and a refrigerator that can contribute to energy saving over a long period of time.
[0068]
A refrigerator and a refrigerator according to the present invention provide a coating material comprising silica as a core material containing at least 1 wt% of an additive having an effect of disintegrating silica aggregate particles by being added between an inner box and an outer box. A refrigerator comprising a heat-insulating box provided with a vacuum heat-insulating material, wherein the space between the vacuum heat-insulating material and the inner box, and the space between the vacuum heat-insulating material and the outer box are filled with urethane foam. It is assumed that.
[0069]
Further, the refrigerator and the refrigerator of the present invention are characterized by comprising a vacuum heat insulating material whose additive is a conductive powder.
[0070]
In addition, the refrigerator and the refrigerator of the present invention have a powder specific resistance of 1 × 10 ⁸ A vacuum heat insulating material having a resistance of less than Ω / cm is provided.
[0071]
Further, the refrigerator and the refrigerator of the present invention are characterized in that the silica comprises a vacuum heat insulating material that is dry silica having an average primary particle diameter of 50 nm or less.
[0072]
Further, the refrigerator and the refrigerator of the present invention are characterized in that the conductive powder is provided with a vacuum heat insulating material that is powdered carbon.
[0073]
A refrigerator and a refrigerator according to the present invention are characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal.
[0074]
The refrigerator and refrigerator of the present invention are characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal oxide.
[0075]
With the above configuration, after clarifying the factors of the heat insulating performance improvement effect that appears when the additive is added to the base material, select the appropriate base material and additive, and compare with the case without powder addition By providing a very high-performance vacuum heat insulating material capable of improving heat insulation performance by 20% or more, it is possible to provide a refrigerator and a refrigerator that can effectively contribute to energy saving. In addition, by using a configuration in which urethane foam is filled between the inner box and the outer box, the strength and appearance of the heat insulating box body are not reduced by applying the vacuum heat insulating material.
[0076]
The notebook computer according to the present invention has a silica containing at least 1 wt% or more of an additive having an effect of breaking up aggregated particles of silica by being added in order to cut off between a heat generating portion inside the device and the device case. A notebook computer provided with a vacuum heat insulating material having a coating material having a core material as a core material, wherein the vacuum heat insulating material is in close contact with the bottom of the device case.
[0077]
The notebook computer according to the present invention is characterized in that the notebook computer includes a vacuum heat insulating material in which the additive is a conductive powder.
[0078]
Further, in the notebook computer of the present invention, the powder specific resistance of the conductive powder is 1 × 10 ⁸ A vacuum heat insulating material having a resistance of less than Ω / cm is provided.
[0079]
The notebook computer according to the present invention is characterized in that the silica is provided with a vacuum heat insulating material that is dry silica having an average primary particle diameter of 50 nm or less.
[0080]
The notebook computer according to the present invention is characterized in that the conductive powder includes a vacuum heat insulating material that is powdered carbon.
[0081]
The notebook computer according to the present invention is characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal.
[0082]
The notebook computer according to the present invention is characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal oxide.
[0083]
With the above configuration, after clarifying the factors of the heat insulating performance improvement effect that appears when the additive is added to the base material, select the appropriate base material and additive, and compare with the case without powder addition By using a very high-performance vacuum heat insulating material capable of improving the heat insulating performance by more than 20%, the heat inside the device is transferred to the surface, so that the user does not feel uncomfortable. A computer can be provided.
[0084]
In addition, since the core material has flexibility because of the vacuum heat insulating material having the above structure, the vacuum heat insulating material adheres well to the bottom of the device case without forming a gap. It is possible to provide a notebook computer that can be effectively used and that does not cause discomfort to the user by transferring heat inside the device to the surface.
[0085]
The notebook computer according to the present invention has a silica containing at least 1 wt% or more of an additive having an effect of breaking up aggregated particles of silica by being added in order to cut off between a heat generating portion inside the device and the device case. A notebook computer provided with a vacuum heat insulating material having a coating material having a core material as a core material, wherein a covering area of the vacuum heat insulating material is larger than an area of the heat generating portion.
[0086]
The notebook computer according to the present invention is characterized in that the notebook computer includes a vacuum heat insulating material in which the additive is a conductive powder.
[0087]
Further, in the notebook computer of the present invention, the powder specific resistance of the conductive powder is 1 × 10 ⁸ A vacuum heat insulating material having a resistance of less than Ω / cm is provided.
[0088]
The notebook computer according to the present invention is characterized in that the silica is provided with a vacuum heat insulating material that is dry silica having an average primary particle diameter of 50 nm or less.
[0089]
The notebook computer according to the present invention is characterized in that the conductive powder includes a vacuum heat insulating material that is powdered carbon.
[0090]
The notebook computer according to the present invention is characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal.
[0091]
The notebook computer according to the present invention is characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal oxide.
[0092]
With the above configuration, after clarifying the factors of the heat insulating performance improvement effect that appears when the additive is added to the base material, select an appropriate base material and additive, and compare with the case without powder addition. By applying a very high-performance vacuum insulation material that can improve the heat insulation performance by more than 20% over a covering area larger than the area of the heat-generating part, it is effective without escaping heat by wrapping around from the end of the vacuum insulation material Since the thermal insulation can be effectively achieved, it is possible to provide a notebook computer that does not cause discomfort to the user by transferring heat inside the device to the surface.
[0093]
The electric water heater of the present invention includes a water storage container, a heater for heating water in the water storage container, a hot water supply path for discharging water to the outside, and a vacuum heat insulating material provided on the outer periphery of the water storage container. Wherein the vacuum heat insulating material is a vacuum heat insulating material having a silica-based coating material containing at least 1 wt% or more of an additive having an effect of breaking up aggregated silica particles by addition. Is what you do.
[0094]
Moreover, the electric water heater of the present invention is characterized in that the additive material is provided with a vacuum heat insulating material whose conductive powder is a conductive powder.
[0095]
Further, the electric water heater of the present invention has a powder specific resistance of 1 × 10 ⁸ A vacuum heat insulating material having a resistance of less than Ω / cm is provided.
[0096]
Further, the electric water heater of the present invention is characterized in that the silica is provided with a vacuum heat insulating material which is dry silica having an average primary particle diameter of 50 nm or less.
[0097]
Moreover, the electric water heater of the present invention is characterized in that the conductive powder includes a vacuum heat insulating material that is powdered carbon.
[0098]
An electric water heater according to the present invention is characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal.
[0099]
The electric water heater according to the present invention is characterized in that the conductive powder includes a vacuum heat insulating material having a composition containing a metal oxide.
[0100]
With the above configuration, after clarifying the factors of the heat insulating performance improvement effect that appears when the additive is added to the base material, select the appropriate base material and additive, and compare with the case without powder addition By providing an extremely high-performance vacuum heat insulating material capable of improving heat insulating performance by 20% or more, an electric water heater that can contribute to energy saving can be provided.
[0101]
In addition, since the vacuum heat insulating material having the above configuration is used, even if it is continuously used in an electric water heater having a temperature of 100 ° C. or more when energized, the temperature dependency of the heat insulating performance is small, and the heat insulating performance deteriorates with time. Because it is very small, it is possible to provide an electric water heater that can contribute to energy saving over a long period of time.
[0102]
In addition, since the vacuum heat insulating material having the above-described configuration has the core material having flexibility, the vacuum heat insulating material can be closely mounted along the outer periphery of the water storage container. Thus, it is possible to provide an electric water heater that can be effectively used and has an excellent energy saving effect.
[0103]
Further, the electric water heater of the present invention is characterized in that a vacuum heat insulating material is applied to the lid portion of the electric water heater, and the factor of the heat insulating performance improving effect that is exhibited when the additive is added to the base material. After selecting the appropriate base material and additive material, a very high-performance vacuum heat insulating material that can improve the heat insulating performance by 20% or more compared to the case where no powder is added is provided. By doing so, it is possible to provide an electric water heater that can contribute to energy saving.
[0104]
In addition, since the vacuum heat insulating material having the above-described structure is used, since the core material has flexibility, it can be applied to a portion having a complicated shape such as a lid, and a more advanced energy saving effect can be obtained. Can be provided.
[0105]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. However, the present embodiment is not limited to these.
[0106]
(Embodiment 1)
FIG. 1 is a cross-sectional view of a vacuum heat insulating material 1 according to one embodiment of the present invention, in which a coating material 2 having a metal foil layer and a thermoplastic polymer layer has wet silica 3 and a powder specific resistance of 0. The powdery carbon material 4 of 0.8 cm / Ω is uniformly dispersed and filled. These powders are sufficiently mixed by a mixing device having stirring blades. The amount of the powdered carbon material added was 5 wt%.
[0107]
After the mixed powder was dried at 110 ° C. for 1 hour, it was inserted into the coating material, and the inside thereof was depressurized to 133 Pa, and the opening was bonded by heat sealing to produce a vacuum heat insulating material.
[0108]
The thermal conductivity of the produced vacuum heat insulating material was measured at an average temperature of 24 ° C. using Auto-λ manufactured by Eiko Seiki Co., Ltd. Further, the aggregated particle size of the mixed powder was measured by E-spurt manufactured by Hosokawa Micron. Table 1 shows the properties of the base material and the additives, and the evaluation results.
[0109]
The vacuum heat insulating material thus configured is superior to the case of wet silica alone due to the effect that the powdered carbon material, which is the conductive material, aggregates the aggregated particles of the wet silica, and crushes and refines with the charged power. It shows the heat insulation performance. The heat insulating performance improving effect in the first embodiment is about 24%.
[0110]
(Embodiment 2)
FIG. 2 is a cross-sectional view of a vacuum heat insulating material 1 according to one embodiment of the present invention, in which a coating material 2 having a metal foil layer and a thermoplastic polymer layer is coated with dry silica 5 having an average primary particle diameter of 55 nm and powder. The carbon black 6 having a body resistivity of 0.6 cm / Ω is uniformly dispersed and filled.
[0111]
The amount of carbon black added was 5 wt%.
[0112]
A vacuum heat insulating material was prepared in the same manner as in Embodiment 1, and the thermal conductivity and the aggregated particle diameter were measured. Table 1 shows the properties of the base material and the additives, and the evaluation results.
[0113]
The vacuum heat insulating material thus configured has a better heat insulating performance than that of the wet silica alone due to the effect that carbon black, which is a conductive material, crushes the aggregated particles of the dry silica by its charging power and makes it finer. It shows. The heat insulation performance improving effect in the second embodiment is about 29%.
[0114]
(Embodiment 3)
FIG. 3 is a cross-sectional view of a vacuum heat insulating material 1 according to an embodiment of the present invention. Carbon black 6 having a powder specific resistance of 0.6 cm / Ω is uniformly dispersed and filled. The amount of carbon black added was 5 wt%.
[0115]
A vacuum heat insulating material was prepared in the same manner as in Embodiment 1, and the thermal conductivity and the aggregated particle diameter were measured. Table 1 shows the properties of the base material and the additives, and the evaluation results.
[0116]
The vacuum heat insulating material thus configured has a more excellent heat insulation than that of fumed silica alone due to the effect that carbon black, which is a conductive material, crushes and aggregates the fumed silica aggregated particles by the charged power. It shows performance. The heat insulation performance improving effect in the third embodiment is about 43%.
[0117]
(Embodiment 4)
FIG. 4 is a cross-sectional view of a vacuum heat insulating material 1 according to one embodiment of the present invention, in which a coating material 2 having a metal-deposited film layer and a thermoplastic polymer layer is coated with fumed silica 7 having an average primary particle diameter of 7 nm. And a tin oxide composition 8 having a powder specific resistance of 1.4 cm / Ω is uniformly dispersed and filled. The addition amount of the tin oxide composition was 5% by weight.
[0118]
A vacuum heat insulating material was prepared in the same manner as in Embodiment 1, and the thermal conductivity and the aggregated particle diameter were measured. Table 1 shows the results.
[0119]
The vacuum heat insulating material thus configured is superior to the case of fumed silica alone due to the effect that the tin oxide composition, which is a conductive material, breaks down the fumed silica aggregated particles by the charged power and makes it finer. It shows the heat insulation performance. The heat insulating performance improvement effect in the fourth embodiment is about 41%.
[0120]
(Embodiment 5)
FIG. 5 is a cross-sectional view of a vacuum heat insulating material 1 according to one embodiment of the present invention, in which a coating material 2 having a metal-deposited film layer and a thermoplastic polymer layer is coated with fumed silica 7 having an average primary particle diameter of 7 nm. And a titanium oxide composition 9 having a powder specific resistance of 12 cm / Ω is uniformly dispersed and filled. The addition amount of the titanium oxide composition was 5 wt%.
[0121]
A vacuum heat insulating material was prepared in the same manner as in Embodiment 1, and the thermal conductivity and the aggregated particle diameter were measured. Table 1 shows the results.
[0122]
The vacuum heat insulating material thus configured is superior to the case of fumed silica alone due to the effect that the titanium oxide composition, which is a conductive material, crushes and aggregates the fumed silica aggregated particles by the charged power. It shows the heat insulation performance. The heat insulating performance improving effect in the fifth embodiment is about 28%.
[0123]
(Embodiment 6)
FIG. 6 is a cross-sectional view of a vacuum heat insulating material 1 according to one embodiment of the present invention, in which a coating material 2 having a metal-deposited film layer and a thermoplastic polymer layer is coated with fumed silica 7 having an average primary particle diameter of 7 nm. And the powder specific resistance value is 4 × 10 ⁷ The calcium carbonate composition 10 of cm / Ω is uniformly dispersed and filled. The addition amount of the calcium carbonate composition was 5% by weight.
[0124]
A vacuum heat insulating material was prepared in the same manner as in Embodiment 1, and the thermal conductivity and the aggregated particle diameter were measured. Table 1 shows the results.
[0125]
The vacuum heat insulating material thus configured is superior to the case of fumed silica alone due to the effect that the calcium carbonate composition, which is a conductive material, crushes the aggregated particles of fumed silica with the charged power and makes them finer. It shows the heat insulation performance. The heat insulation performance improvement effect in the sixth embodiment is about 25%.
[0126]
(Embodiment 7)
FIG. 7 is a cross-sectional view of a vacuum heat insulating material 1 according to one embodiment of the present invention, in which a coating material 2 having a metal-deposited film layer and a thermoplastic polymer layer is coated with fumed silica 7 having an average primary particle diameter of 7 nm. And an iron composition 11 having a powder specific resistance of 0.01 cm / Ω is uniformly dispersed and filled. The addition amount of the iron composition was 5 wt%.
[0127]
A vacuum heat insulating material was prepared in the same manner as in Embodiment 1, and the thermal conductivity and the aggregated particle diameter were measured. Table 1 shows the results.
[0128]
[Table 1]

[0129]
The vacuum heat insulating material thus configured is superior to the case of fumed silica alone due to the effect that the iron composition, which is a conductive material, causes the aggregated particles of fumed silica to be crushed and refined by the charged power. It shows the heat insulation performance. The effect of improving the thermal insulation performance in the seventh embodiment is about 46%.
[0130]
From Table 1 above, it is clear that aggregated particles of silica as a base material are crushed and refined by the addition of the conductive powder, and as a result, an effect of improving thermal conductivity is obtained.
[0131]
Further, the effect is as follows. ⁸ It is high when it is less than Ω / cm, and an improvement effect of 25% or more with respect to the thermal conductivity of the base material can be obtained.
[0132]
Further, the effect is particularly remarkable in the case of fumed silica having an average primary particle diameter of 50 nm or less. Comparing Embodiment 2 and Embodiment 3, the base material has the same additive while using the same additive. Because of the dry silica having an average primary particle diameter of 50 nm or less, the improvement effect was improved from 29% to 43%.
[0133]
In addition, it can be seen that powder carbon having a small powder specific resistance, a composition containing a metal, a composition containing a metal oxide, and the like can obtain a very good heat insulating performance improving effect.
[0134]
(Embodiment 8)
Using a powder having the same configuration as in the first embodiment, a core material sufficiently mixed by a mixing device without a stirring blade is dried at 110 ° C. for 1 hour, inserted into a coating material, and the inside thereof is depressurized to 133 Pa. After that, the opening was bonded by heat sealing to produce a vacuum heat insulating material. When the thermal conductivity was measured, it was necessary to extend the time required for mixing by about 20% in order to obtain the same thermal conductivity as in the first embodiment.
[0135]
This is considered to be because the mixing efficiency is reduced due to the absence of the stirring blade.
[0136]
(Embodiment 9)
FIG. 8 is a cross-sectional view of the refrigerator-freezer 12 of the present invention, in which the vacuum heat insulating material 1 according to the third embodiment is disposed in advance inside a box constituted by an inner box 13 and an outer box 14, and It is characterized in that a space other than the material is foam-filled with a rigid urethane foam 15. In this case, the ratio of the area where the vacuum heat insulating material is applied to the total surface area of the refrigerator is 60%. In the refrigerator constructed as above, fumed silica and carbon black are uniformly dispersed, so that carbon black, which is a conductive material, crushes the aggregated particles of fumed silica and reduces the size of the fumed silica. Effect increases the solid contact points per unit volume, resulting in higher thermal resistance of the solid and lower thermal conductivity of the solid, resulting in better heat insulation performance than fumed silica alone. In addition, since a heat leak is suppressed by using a coating material having a metal-deposited film layer, an excellent energy saving effect is exhibited. When the power consumption was measured, it was 15% lower than when no vacuum heat insulating material was applied, confirming the heat insulating effect.
[0137]
(Embodiment 10)
FIG. 9 is a cross-sectional view of the refrigerator-freezer 12 of the present invention, in which the vacuum heat insulating material 1 according to the third embodiment is disposed in advance inside a box constituted by an inner box 13 and an outer box 14, and It is characterized in that a space other than the material is foam-filled with a rigid urethane foam 15, and a vacuum heat insulating material is also provided between the vicinity of the compressor 17 in the machine room 16 located at the lower part of the refrigerator and the inside 18 of the refrigerator. I have. In this case, the ratio of the area where the vacuum heat insulating material is applied to the total surface area of the refrigerator is 90%. In the refrigerator constructed as above, fumed silica and carbon black are uniformly dispersed, so that carbon black, which is a conductive material, crushes the aggregated particles of fumed silica and reduces the size of the fumed silica. Effect increases the solid contact points per unit volume, resulting in higher thermal resistance of the solid and lower thermal conductivity of the solid, resulting in better heat insulation performance than fumed silica alone. In addition, since a heat leak is suppressed by using a coating material having a metal-deposited film layer, an excellent energy saving effect is exhibited. When the power consumption was measured, it was 25% lower than when no vacuum heat insulating material was applied, and the heat insulating effect was confirmed.
[0138]
(Embodiment 11)
FIG. 10 is a cross-sectional view of the refrigerator-freezer 12 of the present invention, in which the vacuum heat insulating material 1 according to the third embodiment is disposed in advance inside a box constituted by an inner box 13 and an outer box 14, and It is characterized in that a space other than the material is foam-filled with a rigid urethane foam 15, and a vacuum heat insulating material is also provided between the vicinity of the compressor 17 in the machine room 16 located at the lower part of the refrigerator and the inside 18 of the refrigerator. I have. In this case, the ratio of the area where the vacuum heat insulating material is applied to the total surface area of the refrigerator is 90%. In addition, since the spaces of the vacuum heat insulating material and the inner box and the spaces of the vacuum heat insulating material and the outer box are filled with urethane foam, the flatness of the appearance of the refrigerator is improved. In the refrigerator constructed as above, fumed silica and carbon black are uniformly dispersed, so that carbon black, which is a conductive material, crushes the aggregated particles of fumed silica and reduces the size of the fumed silica. Effect increases the solid contact points per unit volume, resulting in higher thermal resistance of the solid and lower thermal conductivity of the solid, resulting in better heat insulation performance than fumed silica alone. In addition, since a heat leak is suppressed by using a coating material having a metal-deposited film layer, an excellent energy saving effect is exhibited. When the power consumption was measured, it was 25% lower than when no vacuum heat insulating material was applied, and the heat insulating effect was confirmed.
[0139]
(Embodiment 12)
FIG. 11 is a cross-sectional view of a notebook computer 19 of the present invention. The vacuum heat insulating material 1 according to the fifth embodiment, which cuts off a space between a heat generating portion 21 on a main board 20 inside the device and the bottom of the device case 22. , A heat radiating plate 23, and the vacuum heat insulating material 1 is in close contact with the bottom of the device case 22. The notebook computer thus configured disperses fumed silica and carbon black uniformly, so that carbon black, which is a conductive material, crushes aggregated particles of fumed silica by the charged power, The solidification point per unit volume increases due to the effect of the solidification, and as a result, the thermal resistance of the solid increases and the thermal conductivity of the solid decreases. The vacuum heat insulating material, which has a heat-leakage suppressed by using a coating material having a metal-deposited film layer, is in close contact with the bottom of the device case in order to effectively block heat transfer to the bottom surface. Therefore, it is highly insulated, and the temperature rise on the surface of the apparatus is suppressed, so that the user does not feel uncomfortable.
[0140]
When the temperature of the bottom surface of the notebook computer was measured, it was 6 ° C. lower than when no vacuum heat insulating material was applied, and the heat insulating effect was confirmed.
[0141]
(Embodiment 13)
FIG. 12 is a cross-sectional view of the notebook computer 19 of the present invention. The vacuum heat insulating material 1 according to the fifth embodiment, which cuts off the space between the heat generating portion 21 on the main board 20 inside the device and the bottom of the device case 22. , A heat radiating plate 23, and the area covered by the vacuum heat insulating material 1 is larger than the area of the heat generating portion 21. The notebook computer thus configured disperses fumed silica and carbon black uniformly, so that carbon black, which is a conductive material, crushes aggregated particles of fumed silica by the charged power, The solidification point per unit volume increases due to the effect of the solidification, and as a result, the thermal resistance of the solid increases and the thermal conductivity of the solid decreases. Vacuum insulation material that has, and the heat leak is also suppressed by the use of a coating material having a metallized film layer, in order to effectively block heat transfer to the bottom surface, in an area larger than the area of the heat generating portion. This prevents heat transfer due to heat sneaking from the end of the vacuum insulation material and effectively shuts off heat transfer to the bottom surface, which suppresses temperature rise on the equipment surface. There is no discomfort to the user. When the temperature of the bottom surface was measured, it was 7 ° C. lower than when no vacuum heat insulating material was applied, and the heat insulating effect was confirmed.
[0142]
(Embodiment 14)
FIG. 13 is a cross-sectional view of the electric water heater 24 of the present invention, which shows an outer container 25, a water storage container 26, a lid 27, a heater 28 for heating water in the water storage container, and an outer periphery of the water storage container. And the vacuum heat insulating material 1 according to the fifth aspect. In addition, a vacuum heat insulating material is attached to the vicinity of the heater attached to the lower part of the water storage container. The electric water heater configured in this way uniformly disperses fumed silica and carbon black, so that carbon black, which is a conductive material, disintegrates fumed silica aggregates and reduces the size of the fumed silica using the charged power. Effect increases the solid contact points per unit volume, resulting in higher thermal resistance of the solid and lower thermal conductivity of the solid, resulting in better heat insulation performance than fumed silica alone. In addition, since a vacuum heat insulating material in which heat leak is suppressed by using a coating material having a metal-deposited film layer is applied, an excellent energy saving effect is exhibited. When the power consumption was measured, it was 10% lower than when no vacuum heat insulating material was applied, confirming the heat insulating effect.
[0143]
(Embodiment 15)
FIG. 14 is a cross-sectional view of the electric water heater 24 of the present invention, in which an outer container 25, a water storage container 26, a lid 27, a heater 28 for heating water in the water storage container, an outer periphery of the water storage container, and , And the vacuum heat insulating material 1 according to the fifth embodiment of the lid. In addition, a vacuum heat insulating material is attached to the vicinity of the heater attached to the lower part of the water storage container. The electric water heater configured in this way uniformly disperses fumed silica and carbon black, so that carbon black, which is a conductive material, disintegrates fumed silica aggregates and reduces the size of the fumed silica using the charged power. Effect increases the solid contact points per unit volume, resulting in higher thermal resistance of the solid and lower thermal conductivity of the solid, resulting in better heat insulation performance than fumed silica alone. In addition, since a vacuum heat insulating material in which heat leak is suppressed by using a coating material having a metal-deposited film layer is applied, an excellent energy saving effect is exhibited. When the power consumption was measured, it was 12% lower than when no vacuum heat insulating material was applied, and the heat insulating effect was confirmed.
[0144]
(Embodiment 16)
FIG. 15 shows a mixing vessel 30 having stirring blades 29 in the method for producing a vacuum heat insulating material of the present invention, which is present in the raw material because the mixing vessel having stirring blades is used in the powder uniform dispersion step. Secondary or tertiary aggregates of fumed silica can be broken. As a result, the fumed silica and the powdered carbon material can be uniformly dispersed, so that deterioration of the heat insulation performance due to a partial decrease in the degree of dispersion can be suppressed.
[0145]
The vacuum heat insulating material of the present invention comprises a core material and a coating material, and the core material is sealed in the coating material under reduced pressure. Also, moisture adsorbents such as physical adsorbents such as synthetic zeolite, activated carbon, activated alumina, silica gel, dawsonite and hydrotalcite, and chemical adsorbents such as oxides and hydroxides of alkali metals and alkaline earth metals. Alternatively, a gas adsorbent may be used. After the core material as a powder is sealed with a nonwoven fabric, the core material may be further sealed with a coating material. Before the vacuum sealing, a drying step of the core material may be added. Further, the powder may be solidified by using a binder or pressure and used.
[0146]
In addition, the refrigerator and the refrigerator of the present invention refer to a device utilizing hot / cold heat in a range from the operating temperature range of −30 ° C. to a normal temperature and a higher temperature, such as a vending machine. Further, the present invention is not limited to electric equipment, but also includes gas equipment and the like.
[0147]
Further, the notebook computer of the present invention is described as a representative example of a device that requires heat insulation in the operating temperature range from room temperature to around 80 ° C., and is not particularly limited to this. For example, it can also be used for heat insulation of a liquid crystal part of a car navigation system having a liquid crystal panel and a heat generating part by a CPU.
[0148]
Further, the electric water heater of the present invention is described as a representative of equipment which requires heat insulation in a range from an ordinary temperature, which is an operating temperature range, to around 100 ° C., for example, a rice cooker, a dish dryer, and the like. Available. Further, the present invention is not limited to electric equipment, but also includes gas equipment and the like.
[0149]
As the conductive powder of the present invention, any powder having conductivity can be used. As a rough guide, the powder specific resistance value is 1 × 10 ^Thirteen cm / Ω or less. In the case of an inorganic powder, for example, a metal powder, a metal oxide powder, a carbonate powder, a chloride powder, a powdered carbon, or the like, and in the case of an organic powder, a metal-doped powder. . Powder specific resistance value is 1 × 10 ⁸ cm / Ω or less is more preferable. Further, when high heat insulation performance is required, the density is preferably 10 cm / Ω or less. Also, considering that the powder is uniformly mixed with the base material, it can be said that the finer the powder diameter, the better.
[0150]
The effect can be obtained if the amount of the conductive powder added is 1 wt% or more. Although the optimum amount of addition varies depending on the type of powder to be added, the effect of improving the heat insulating performance tends to increase as the amount of addition increases. However, even if added in an amount of 40% or more, the effect often reaches saturation. Therefore, it can be said that the optimal addition amount is about 3% to 30%.
[0151]
The silica of the present invention refers to a silicon oxide compound, and wet silica, dry silica, aerogel and the like can be used. Further, it also includes a powder containing silica as a main component and other components.
[0152]
As the fumed silica of the present invention, a silicon oxide compound having various particle sizes produced by a dry process, such as silicic acid produced by an arc method and silicic acid produced by pyrolysis, can be used. These fumed silicas have a relatively low electrostatic force between aggregated particles, and have a high aggregation-crushing effect when a conductive powder is added. Further, the primary particle diameter is preferably 50 nm or less because of excellent heat insulation performance, and particularly when high heat insulation performance is required, the primary particle diameter is preferably 10 nm or less. Also, mixtures of dry silica particles having various particle sizes can be used. For example, it is possible to use even a non-regular lot product in which the particle size generated at the time of production switching between the mass-produced product A and the mass-produced product B having a prescribed particle size is not suppressed between A and B. It is possible to manufacture a vacuum heat insulating material at a lower cost.
[0153]
The powdered carbon material of the present invention can be used as long as it is a powdered carbon material such as carbon black, graphitized carbon powder, activated carbon, and acetylene black. Because it is versatile and inexpensive, it is easy to use carbon black.However, when using carbon black, it suppresses gas generation over time and maintains excellent heat insulation performance over a long period of time. 100m ² / G is preferred. For the same reason, the use of graphitized carbon powder is also preferable.
[0154]
The composition containing a metal of the present invention can be applied as long as it contains a metal as a composition and has a conductive property. For example, iron, copper, gold, platinum and the like can be applied. These may be included as main components, and other substances may be present.
[0155]
The composition containing the metal oxide of the present invention can be applied as long as the composition contains the metal oxide and has a conductive property. For example, titanium oxide, zinc oxide, tin oxide, etc. These may be included as main components, and other substances may be present.
[0156]
As the coating material of the present invention, a material capable of blocking the core material from the outside air can be used. For example, it is a thin metal plate such as stainless steel, aluminum, or iron, or a laminate of a thin metal plate and a plastic film. It is preferable that the laminate material is constituted by a surface protection layer, a gas barrier layer, and a heat welding layer. As the surface protective layer, a stretched product of a polyethylene terephthalate film or a polypropylene film can be used, and if a nylon film or the like is provided on the outside, the flexibility is improved, and the bending resistance and the like are improved. As the gas barrier layer, a metal foil film such as aluminum or a metal vapor-deposited film can be used, but a metal vapor-deposited film is preferable in order to further suppress heat leak and exhibit an excellent heat insulating effect. Vapor deposition on a polyethylene terephthalate film, an ethylene / vinyl alcohol copolymer resin film, polyethylene naphthalate film or the like is preferable. Further, as the heat welding layer, a low density polyethylene film, a high density polyethylene film, a polypropylene film, a polyacrylonitrile film, a non-stretched polyethylene terephthalate film and the like can be used.
[0157]
The mixing vessel having a stirring blade in the method for producing a vacuum heat insulating material of the present invention may be used as long as it has a stirring blade capable of breaking secondary or tertiary aggregates of silica present in the raw material. can do. Even if the mixing container is cylindrical, spherical, or cubic, it can be applied irrespective of the shape. In addition, in addition to mixing using a stirring blade, a mixing container that can be rotated by itself or a bottom rotor, and that can rotate and mix the powder can be used, and the time required for mixing and dispersing is further reduced. You.
[0158]
Next, comparative examples for the present invention will be described.
[0159]
(Comparative Example 1)
The core material of the vacuum heat insulating material has a stirring blade of 95 wt% of pearlite powder having an average particle diameter of 7.2 μm as a base material and 5 wt% of carbon black having a powder specific resistance of 0.6 Ω / cm as an additive. What was uniformly mixed in the mixing container was used. The core material was filled in a coating material having a metal foil layer and a thermoplastic polymer layer, and sealed with a heat fusion device at a pressure of 133 Pa to obtain a vacuum heat insulating material.
[0160]
When the thermal conductivity of this vacuum heat insulating material was measured, it was 0.0072 kcal / mh ° C. The thermal conductivity when the pearlite powder alone was used as a vacuum heat insulating material was 0.0065 kcal / mh ° C., and deterioration of the heat insulation performance was confirmed by adding 5 wt% of carbon black to the pearlite powder.
[0161]
The thermal conductivity when carbon black is similarly evaluated as a vacuum heat insulating material is 0.0220 kcal / mh ° C., and it is considered that pearlite and carbon black exhibit the thermal conductivity according to the blend ratio.
[0162]
Therefore, it is considered that the effect of improving the thermal conductivity was not obtained even when a conductive material was added, because the base material had a particle structure that was not disintegrated by electric charging. This also suggests that the effect of improving the thermal conductivity by adding carbon black is not due to the improvement in radiant heat conduction.
[0163]
(Comparative Example 2)
The core material of the vacuum heat insulating material includes 95 wt% of fumed silica having an average primary particle diameter of 7 nm as a base material, and a non-conductive powder as an additive. ¹⁶ A mixture obtained by uniformly mixing 5 wt% of an aluminum oxide composition having a resistance of Ω / cm in a mixing vessel having stirring blades was used. The core material was filled in a coating material having a metal foil layer and a thermoplastic polymer layer, and sealed with a heat fusion device at a pressure of 133 Pa to obtain a vacuum heat insulating material.
[0164]
When the thermal conductivity of this vacuum heat insulating material was measured, it was 0.0053 kcal / mh ° C. The heat transfer coefficient when the fumed silica alone is used as a vacuum heat insulating material is 0.0055 kcal / mh ° C., and improvement of the heat insulating performance cannot be confirmed by adding 5 wt% of the aluminum oxide composition to the fumed silica. Was.
[0165]
This is thought to be because the aluminum oxide composition has almost no conductivity, and thus has no effect of breaking up and miniaturizing the aggregated particles of fumed silica, and as a result, does not affect the heat insulating performance. The thermal conductivity of the aluminum oxide composition alone used in this comparison was 0.0075 kcal / mh ° C.
[0166]
【The invention's effect】
As described above, according to the present invention, in order to clarify the heat insulating performance improvement factors that appear when an additive is added to a base material, by selecting an appropriate base material and an additive according to the theory, It is possible to provide a very high-performance vacuum heat insulating material capable of improving heat insulating performance by 20% or more as compared with the case where no powder is added, and a method of manufacturing the vacuum heat insulating material. In addition, a device that can contribute to energy saving can be provided by including a high-performance vacuum heat insulating material. In addition, by providing a high-performance vacuum heat insulating material, it is possible to provide a device that does not cause discomfort to the user by transmitting heat inside the device to the surface.
[Brief description of the drawings]
FIG. 1 is a sectional view of a vacuum heat insulating material according to an embodiment of the present invention.
FIG. 2 is a sectional view of a vacuum heat insulating material according to one embodiment of the present invention.
FIG. 3 is a sectional view of a vacuum heat insulating material according to an embodiment of the present invention.
FIG. 4 is a sectional view of a vacuum heat insulating material according to one embodiment of the present invention.
FIG. 5 is a sectional view of a vacuum heat insulating material according to an embodiment of the present invention.
FIG. 6 is a sectional view of a vacuum heat insulating material according to one embodiment of the present invention.
FIG. 7 is a sectional view of a vacuum heat insulating material according to an embodiment of the present invention.
FIG. 8 is a sectional view of a refrigerator-freezer according to an embodiment of the present invention.
FIG. 9 is a sectional view of a refrigerator-freezer according to an embodiment of the present invention.
FIG. 10 is a sectional view of a refrigerator-freezer according to an embodiment of the present invention.
FIG. 11 is a cross-sectional view of a notebook computer according to an embodiment of the present invention.
FIG. 12 is a sectional view of a notebook computer according to an embodiment of the present invention;
FIG. 13 is a cross-sectional view of an electric water heater according to an embodiment of the present invention.
FIG. 14 is a sectional view of an electric water heater according to an embodiment of the present invention.
FIG. 15 is a partial cross-sectional view of a mixing container according to one embodiment of the present invention.
FIG. 16 is a characteristic diagram showing a radiant energy distribution of powdered carbon-added silica, silica alone, and an ideal black body (50 ° C.).
FIG. 17 is a characteristic diagram showing a relationship between a powder specific resistance value of an additive and a thermal conductivity of a vacuum heat insulating material.
[Explanation of symbols]
1 vacuum insulation
2 Coating material
3 Wet silica
4 powdered carbon material
5 Dry silica
6 carbon black
7 Fumed silica
8 Tin oxide composition
9 Titanium oxide composition
10 Calcium carbonate composition
11 Iron composition
12 Freezer refrigerator
13 inner box
14 Outer box
15 Rigid urethane foam
16 Machine room
17 Compressor
18 Inside the warehouse
19 Notebook computer
20 Main board
21 Heating part
22 Equipment case
23 Heat sink
24 electric water heater
25 outer container
26 Water storage container
27 Lid
28 heater
29 stirring blades
30 mixing containers

Claims (15)

Increasing the heat insulation performance by reducing solid heat conduction by disintegrating silica aggregate particles rather than radiant heat conduction. Additives made of conductive powder having a powder specific resistance of 10 Ω / cm or less. A vacuum heat insulating material for use in equipment that requires heat insulation in the range of -30 ° C to 100 ° C using fumed silica having an average primary particle diameter of less than 10 nm as a core material. 2. The vacuum heat insulating material according to claim 1 , wherein the conductive powder is powdered carbon. 2. The vacuum heat insulating material according to claim 1 , wherein the conductive powder has a composition containing a metal. 2. The vacuum heat insulating material according to claim 1 , wherein the conductive powder has a composition containing a metal oxide. At least, in a mixing vessel having stirring blades, fumed silica having an average primary particle diameter of less than 10 nm and a powder specific resistance value that enhances heat insulation performance by reducing solid heat conduction by agglomerating particles of silica from reduction of radiant heat conduction have a reduced powder specific resistance value. A powder uniform dispersion step of adding an additive made of a conductive powder of 10 Ω / cm or less to the fumed silica in an amount of 1 wt% or more and less than 40 wt% , and uniformly dispersing the mixture by mixing with a stirring blade; A vacuum sealing step in which the core material is covered with a coating material under reduced pressure; and manufacturing a vacuum heat insulating material used for equipment requiring heat insulation in a range of -30 ° C to 100 ° C. Method. The method according to claim 5, wherein the conductive powder is powdered carbon. The method according to claim 5, wherein the conductive powder has a composition including a metal. The method for producing a vacuum heat insulating material according to claim 5, wherein the conductive powder has a composition containing a metal oxide. A heat insulating box provided with the vacuum heat insulating material according to any one of claims 1 to 4 between an inner box and an outer box, the heat insulating box having an area where the vacuum heat insulating material is applied to the entire surface area of the refrigerator-freezer. A refrigerator using a vacuum heat insulating material, wherein the ratio is 3% or more and 90% or less. An insulating box provided with the vacuum heat insulating material according to any one of claims 1 to 4 between an inner box and an outer box, and a machine room provided with a compressor below the insulating box, A refrigerator using a vacuum heat insulating material, wherein the heat insulating material is disposed between the machine room and the inner box. A heat insulating box provided with the vacuum heat insulating material according to claim 1 between the inner box and the outer box, wherein the vacuum heat insulating material and the inner box, and the vacuum heat insulating material and the outer box are provided. A refrigerator using vacuum heat insulating material, characterized in that all spaces are filled with urethane foam. The vacuum heat insulating material according to any one of claims 1 to 4, wherein the vacuum heat insulating material is in close contact with a bottom of the device case for shutting off a heat generating portion inside the device of the notebook computer and the device case. A notebook computer using a vacuum heat insulating material. The vacuum heat insulating material according to any one of claims 1 to 4 for shutting off a heat generating portion inside the device of the notebook computer and the device case, at least a covering area of the vacuum heat insulating material, A notebook computer using a vacuum heat insulating material, wherein the notebook computer is larger than the heat generating area. A water storage container, a heater for heating water in the water storage container, a hot water supply path for discharging water to the outside, and a vacuum heat insulating material provided on an outer periphery of the water storage container, wherein the vacuum heat insulating material is provided from claim 1. Item 5. An electric water heater comprising the vacuum heat insulating material according to any one of Items 4. An electric water heater characterized in that the vacuum heat insulating material according to any one of claims 1 to 4 is applied to a lid of the electric water heater.

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