JPWO2003087004A1 - Solar heat insulation glass and solar heat insulation method using the same - Google Patents
Solar heat insulation glass and solar heat insulation method using the same Download PDFInfo
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Abstract
ガラス本来の可視光線の透明度を損なうことなく、日射による熱負荷を低減することができる安価な日射熱遮断ガラスを提供することを課題とし、ガラス基板の片面に、可視光線透過率がガラス基板のそれより大きく、且つ日射熱吸収率及び常温熱放射の波長域における放射熱吸収率が共にガラス基板のそれより小さい被膜を塗布等により形成し、得られる日射熱遮断ガラスを、該被膜形成面が閉鎖空間内部に向くように設置して、日射により加熱されたガラスから内部への熱放射を遮断し、内部の熱負荷を低減させる。The objective is to provide an inexpensive solar heat-shielding glass that can reduce the heat load due to solar radiation without impairing the transparency of the glass's original visible light. A film having a surface on which the film is formed is formed by applying a film having a larger solar radiation absorption rate and a radiation heat absorption rate in the wavelength region of room temperature thermal radiation smaller than that of the glass substrate by coating or the like. It is installed so as to face the inside of the enclosed space, and the heat radiation from the glass heated by solar radiation to the inside is cut off to reduce the internal heat load.
Description
技術分野
本発明は、ガラス基板に常温熱放射の波長域における熱放射が小さい被膜を設けた新規な日射熱遮断ガラスに関する。詳しくは、本発明は、日射により加熱されて温度上昇したガラス面からの熱放射（常温熱放射の波長域における熱放射）を遮断することにより、日射熱放射を遮断することができる日射熱遮断ガラス、及びそれを用いた日射熱遮断方法に関する。
背景技術
一般に、建物や車両などのガラス窓を有する閉鎖空間をもつものにおいては、ガラス面が日射により加熱されて高温となり、そのガラスに吸収された日射熱が室内や車内などの閉鎖空間内部に放射されて内部の温度が上昇し、特に夏期等にエアコンの効きが悪くなるなどの様々な問題を引き起こす場合がある。
このような日射熱の放射を遮断するために、従来より、各種の無機質又は有機質の物質を用いた日射を吸収する熱線吸収ガラスや日射を反射する熱線反射ガラスなどが開発されている。しかし、これらはガラスを透過して直接閉鎖空間内に入射する日射熱を遮断させるために、日射熱そのものを吸収する有機物や無機物を用いたり、日射熱を反射する金属や無機物などを用いたりするものである。
このような日射熱を直接吸収したり反射したりする熱線吸収ガラスや熱線反射ガラスにおいて、その日射熱遮断効果を高めるには、日射熱を吸収したり反射したりする物質を増加させる方法があるが、コストが高くなる、あるいは可視光線帯域の透明度が大きく低下するため内部が暗くなる、などの実用面での不利を伴う。
また、日射熱を吸収するガラスは、ガラスに吸収された熱が、時間をおいて、再度内部に熱放射されるので、閉鎖空間内部の熱負荷の低減は大きく見込めないという欠点があった。
一方、日射熱を反射するガラスは、常温熱放射の波長域の波長をほとんど吸収しないので再放射の原因とはならないが、これらも同様に、赤外線を反射させる金属やセラッミクスなどを用いているので、可視光線まで反射して中が暗くなる欠点があった。
これらのことを解決するために金属層を中央に配置して、その両側に金属カバー層を形成することにより屈折率を調整し可視光線透過率を７０％程度まで上げて、ガラスに貼着することにより赤外線を反射させる多層系の保温材（特開昭５９−１０３７４９）や、放射を低下させる低放射膜としてＳｎＯ２：Ｆ膜を用いて、色ムラを低減させるためにＳｎＯ２膜とＳｉＯ２膜をガラス基板との中間に積層した低放射ガラスと該低放射ガラスを使用したガラス物品（特開２００１−２４４９）などがあるが、可視光線帯域の透明度はいまだ充分とはいえない。
また、これらのガラスやフィルムを作成するには、金属やセラミックスをガラスにコートさせるために、真空蒸着やスパッタリングなどの装置を用いなければならず、経済的にも大きく不利となる。
これらのことから、可視光線帯域における透明度が高く、且つ日射による熱負荷を低減できる安価な日射熱遮断ガラスが待たれていた。
発明の開示
上述したように、今日市場では、ガラス本来の可視光線の透過を損なうことなく、夏期等の日射による熱負荷を低減できるガラスを安価に提供することが望まれていた。特に、可視光帯域における透明度が必要な車両においては大きな要望があった。
しかし、上記の従来技術は、日射による熱負荷を低減させるために可視光線の透過を犠牲にしなければならず、今日の市場ニーズに合致した可視光線帯域の透明度が高く、安価な窓用ガラスを得ることはできていない。
本発明は、このような問題を解決して、ガラス本来の可視光線の透明度を損なうことなく、日射による熱負荷を低減することができる安価な日射熱遮断ガラスを提供することを課題とする。
本発明者らは、上記課題に鑑み鋭意検討した結果、ガラス基板の片面に、可視光線透過率が大きく日射熱吸収率及び常温熱放射の波長域における放射熱吸収率が小さくなるように被膜を形成した複合ガラスを用い、被膜面を閉鎖空間すなわち建物や車両などの内部へ向けて配置することにより、日射を吸収して高温となったガラス基板から閉鎖空間内部への、常温熱放射の波長域における熱放射を有効に遮断し、閉鎖空間内部の熱負荷が低減できることを見出し、本発明を完成した。
すなわち、本発明は、以下の（１）〜（５）に示す日射熱遮断ガラス及びそれを用いた日射熱遮断方法に関する。
（１） ガラス基板の片面に、可視光線透過率が前記ガラス基板の可視光線透過率より大きく、且つ日射熱吸収率及び常温熱放射の波長域における放射熱吸収率が共に前記ガラス基板の日射熱吸収率及び常温熱放射の波長域における放射熱吸収率より小さい被膜を設けたことを特徴とする、日射熱遮断ガラス。
（２） 前記被膜の可視光線透過率が９０％以上、日射熱吸収率が０．０１〜１１％、及び常温熱放射の波長域における放射熱吸収率が０．０１〜２０％であることを特徴とする、（１）記載の日射熱遮断ガラス。
（３） 前記放射熱吸収率における常温熱放射の波長域が５〜５０μｍである、（１）又は（２）記載の日射熱遮断ガラス。
（４） 前記被膜を形成する材料が、アクリル樹脂、シリコーン樹脂、及びスチレン樹脂からなる群から選択されるプラスチックスである、（１）〜（３）のいずれかに記載の日射熱遮断ガラス。
（５） （１）〜（４）のいずれかに記載の日射熱遮断ガラスを、前記ガラス基板面が日射熱の照射される側に向くように配置して、前記被膜面側からの熱放射を遮断することを特徴とする、日射熱遮断方法。
ガラスは、太陽光線から照射される日射熱等の照射熱を吸収する。ここで、太陽光線の波長範囲は０．３μｍ〜３．０μｍであるが、通常、一般的な透明板ガラスにおいても２．５μｍ以上の赤外線帯域の吸収ばかりでなく、２．５μｍ以下の可視光線、近赤外線も吸収する。そして、その日射熱の吸収によりガラスの温度は上昇し、ガラスに吸収された熱は、対流、放射により室内側または外気へ放熱される。
ここで、室内や車内などの閉鎖された空間内部の空気の対流は小さいので、対流熱伝達は比較的小さい。一方、放射による熱伝達は、ガラスと中の物体や空気との間の直接の熱伝達であり、空気の対流にはほとんど影響されない。つまり、高温となったガラスから空間内部に入射する熱は、閉鎖空間内においては、放射による熱伝達の割合が大きくなる。
また、ガラスに吸収される日射熱は、ガラスの厚さが厚くなるほど大きくなり３ｍｍガラスにおいても約６％以上になる。そして、ガラスからの熱放射は、閉鎖空間内においては大きな熱負荷となる。したがって、ガラスに吸収された日射熱が再放射により閉鎖空間内に入射するのを阻止して、外気に多く放射させれば、閉鎖空間内の熱負荷の低減を図ることができると考えられる。
また、太陽光線から照射される波長の範囲は０．３μｍ〜３．０μｍであるが、日射熱を吸収して温度が高くなったガラスから放射される波長の範囲は５μｍ〜５０μｍの常温熱放射の波長域である。したがって、ガラスに吸収された熱が放射により閉鎖空間内部に入射することを阻止するには、少なくとも５μｍ〜５０μｍの波長域の熱放射を遮断すればよい。
固体から空気中に伝達される熱は、固体中を伝導で伝達し、そして、固体表面から対流、放射により空気中へ伝達される。したがって、ガラスからの熱放射を遮断するには、ガラス表面の放射率を小さくすれば良い。すなわち、ガラス表面の常温熱放射の波長域の吸収率を小さくすれば良い。つまり、常温熱放射の波長域５μｍ〜５０μｍにおいて吸収率の小さい物体からなる被膜を、ガラスの表面に形成すればよい。そして、かかる被膜を形成した面を閉鎖空間の内側に向けて配置することにより、ガラスと中の物体との間の放射熱伝達量は減少する。
一方、ガラス表面に形成された被膜自体の日射熱吸収率がガラスより大きくなると、ガラスを透過した日射熱がガラスだけの場合より被膜に多く吸収され、その熱が外気側に放熱されるときガラスが放熱を阻害するため被膜のに吸収された熱のほとんどは閉鎖空間の内側に放出される。すなわち、被膜の日射熱吸収率がガラスより大きくなると、常温熱放射の波長域における放射熱吸収率がガラスより小さくても閉鎖空間内の温度が高くなることとなる。よって、被膜の放射の波長域における放射熱吸収率のみならず、日射熱吸収率も、ガラスから閉鎖空間内部への放射熱伝達量に関係していることがわかる。
一般に、有機物は無機物と異なり可視光線帯域および赤外線帯域の吸収、反射が小さく透過が大きい。したがって、赤外線帯域の吸収、反射が小さく透過が大きいプラスチックスからなる被膜をガラスの片面に形成して、その被膜を閉鎖空間の内側に向けて配置すれば、ガラスの可視光線透過率をほとんど低下させずに空間内部の熱負荷を低減できると考え、実験により被膜の可視光線透過率、日射熱吸収率、常温熱放射における波長域の吸収率の関連を見出し、本発明を完成したものである。
以下、本発明を詳細に説明する。
１．日射熱遮断ガラス
本発明の日射熱遮断ガラスは、ガラス基板の片面に特定の被膜を設けたものである。
（１）ガラス基板
本発明でガラス基板に用いられるガラスの種類には、特に制限はなく、透明板ガラスのみならず、熱線吸収ガラス、熱線反射ガラスなどであってもよい。日射を受けて吸収した日射熱を放射しうる性質を有するものであれば、いずれも本発明の効果を十分発揮することができる。
熱線吸収ガラス、熱線反射ガラスなどは、さらに片面に本発明の前記被膜を形成することにより、直接入射する日射を阻止するとともに、日射を吸収して高温となったガラスからの熱放射も阻止できるので、本発明の熱負荷の低減効果がさらに向上する。
ガラス基板の厚さについても特に制限はないが、好ましくは０．１〜２０ｍｍ、より好ましくは１〜２０ｍｍである。ガラスの素材が同じでも、厚さが厚くなればなるほど日射熱吸収率は増加してガラスからの熱放射が増加するので、ガラスからの熱放射を遮断する効果は大きくなる。
（２）被膜
本発明でガラス基板の片面に設けられる被膜は、可視光線透過率が前記ガラス基板のそれより大きく、且つ日射熱吸収率及び常温熱放射の波長域における放射熱吸収率が共にガラス基板のそれより小さいものである。
▲１▼可視光線透過率、日射熱吸収率及び放射熱吸収率
ここで、放射熱伝達量と、物質の可視光線透過率、日射熱吸収率及び放射熱吸収率との関係について以下に述べる。
＜放射熱伝達量と物体の放射率との関係＞
放射熱伝達における放射熱Ｑは、次の式で表わされ、これは真空中においても伝達可能である。
Ｑ＝σ・ε・（Ｔ／１００）４
ただし、σはステファン・ボルツマン定数、εは物体の放射率、Ｔは物体の絶対温度である。この式から明らかなように、放射率を小さくすればその物体から放射される熱量は少なくなる。
また、物体表面から低温帯域の流体等の物体に伝達される放射熱伝達（放射伝熱）による熱伝達量Ｑ２は、式で表すと次のようになる。
Ｑ２＝σ×ｆ（ε）×［（Ｔｒ／１００）４−（Ｔ０／１００）４］
ただし、σはステファン・ボルツマン定数、ｆ（ε）は物体間の放射伝熱の放射係数、Ｔｒは物体の表面温度（Ｋ）、Ｔ０は低温帯域の物体の表面温度（Ｋ）である。
この式から明らかなように、物体表面間の放射伝熱の放射係数を小さくすれば、その物体間の放射熱伝達量は減少する。
そして、放射伝熱係数は次の式で表される。
ｆ（ε）＝１／（１／ε１）＋（１／ε２）−１
ただし、ε１＝高温帯域側の物質の放射率、ε２＝低温帯域側の物質の放射率。
したがって、物体間の一方の放射率を小さくすれば、放射伝熱係数ｆ（ε）は小さくなり放射熱伝達量は減少する。
すなわち、ガラスの両側に同じ物体があるとガラス表面からの放射による熱伝達は同じになる。したがって、ガラスの片面に放射率の小さい物質からなる被膜を形成すると、被膜を形成した面の放射率は小さくなるので、被膜を形成した面と物体間の放射伝熱係数も小さくなり、被膜が形成されていないガラス表面からの放射熱伝達量に対して減少する。
つまり、閉鎖された建物や車両などに設けられた窓ガラスの室内側表面に放射率の小さい物質からなる被膜を形成すると、日射を受けて高温となったガラスの室内側表面と、室内（閉鎖空間内部）にある空気等の物質や内部の物体との間の放射熱伝達量は減少し、ガラスに吸収された熱は外気に多く放熱されるので、内部の熱負荷は低減される。
＜物体の放射率と放射熱吸収率との関係＞
通常、金属のような物体は、日射熱等の一部を吸収して、他をすべて反射するので吸収率α、反射率ρの間に次の関係式「α＋ρ＝１」が成り立ち、可視光線、赤外線帯域において透過しないことが分かる。しかし、ガラスやプラスチックスなどの物体は、日射熱等を一部吸収し、一部反射し、さらに一部透過する灰色体である。このような灰色体の場合は、吸収率α、反射率ρ及び透過率τの間に次の関係式「α＋ρ＋τ＝１」が成り立ち、可視光線、赤外線帯域において透過する放射熱があることが分かる。
キルヒ・ホッフの法則によると、かかる熱の吸収率と放射率とは等しいので、日射により高温となったガラスからの放射熱を遮断させるには、かかるガラスからの熱放射の波長範囲、すなわち常温熱放射における波長域において、透過が大きく、放射熱の吸収率（放射熱吸収率）の小さい物質を選択すればよい。このときの常温熱放射の波長域は５〜５０μｍの範囲である。
すなわち、５〜５０μｍの波長域において放射熱吸収率の小さいプラスチックス等の物質を選択してガラスの表面に被膜を形成させれば、その被膜表面からの放射熱伝達量は減少する。
このように、本発明の日射熱遮断ガラスに用いられる被膜は、その可視光線透過率がガラス基板の可視光線透過率より大きく、且つその日射熱吸収率がガラス基板の日射熱吸収率より小さく、さらにその常温熱放射の波長域における放射熱吸収率がガラス基板の常温熱放射の波長域における放射熱吸収率より小さいものである。好ましくは、可視光線透過率が９０％以上、日射熱吸収率が０．０１〜１１％、及び常温熱放射の波長域における放射熱吸収率が０．０１〜２０％である。更に好ましくは、可視光線透過率が９２％以上、日射熱吸収率が０．０９〜１１％、及び常温熱放射の波長域における放射熱吸収率が０．４８〜１７％である。
可視光線透過率が上記範囲より小さいと、透明感の高い日射熱遮断ガラスは得られない。また、日射熱吸収率及び放射熱吸収率が上記範囲より高いと、閉鎖空間内部への熱放射を効率よく遮断することができず、内部の熱負荷を低減させる本発明の効果が十分に発揮されない。
▲２▼被膜の材質
一般的に、反射率の大きい金属やセラミックスなどの物質は、可視光帯域と常温熱放射における波長域において同じように反射するので、常温熱放射における波長域の反射を大きくして放射熱吸収率を小さくさせようとすると、可視光帯域における反射率まで大きくなり透明度が低くなってしまう。しかし、一般的に、プラスチックス等の灰色体は、可視光帯域と常温熱放射における波長域の透過率が大きく、吸収率の小さい物質である。
そして、ランバート・ベールの法則によると物質の厚さを薄くすれば薄くするほど透過率が大きくなる。つまり、プラスチックス等の灰色体を薄く形成して常温熱放射における波長域の透過率を大きくして吸収率が小さくなるように被覆すると、被膜の可視光線の透過率も大きくなる。したがって、ガラスの片面にプラスチックス等の灰色体の薄い被膜を形成してもガラスの可視光線帯域の透過率の低減はほとんどなく、ガラス本来の透明度を損なうことはない。
そして、その薄い被膜面を閉鎖された空間すなわち建物や車両などの内部（室内又は車内）側へ向けて配置すると、透明度が高く、且つガラスが吸収した熱を内部に入射させず、その熱を外気に多く放射させて内部の熱負荷を低減させる日射熱遮断ガラスを得ることができる。
このように、本発明の被膜の材料としては、可視光線透過率が大きく日射熱吸収率及び常温熱放射の波長域における放射熱吸収率の小さい物質を用いるのが好ましい。
したがって、被膜の材料としては、上記条件を満たす限り特に制限はないが、好ましくはプラスチックス、例えば、ポリエチレン、ポリプロピレン、ポリイソブチレン、ポリスチレン、ポリ酢酸ビニル、エチレン・酢酸ビニル共重合体、ポリビニルアルコール、ポリ塩化ビニル、塩化ビニル・塩化ビニリデン共重合体、ポリアクリロニトリル、ポリビニルピロリドン、ポリアクリル酸、ポリメタクリル酸メチル、メタクリル酸メチル・スチレン共重合体、ポリメタクリル酸ブチル、ケイ素樹脂、ブタジエンゴム、ブチルゴム、クロロプレンゴム、ポリカーボネート、ポリエチレンテレフタレート、ポリブチレンテレフタレート、酢酸セルロース、ジアリルフタレート樹脂、尿素樹脂、メラミン樹脂、ポリビニルブチラール、塩化ビニル・酢酸ビニル共重合体、エチレン・α−オレフィン共重合体、エチレン・塩化ビニル共重合体、アクリル酸・塩化ビニル共重合体、ポリメチルペンテン、ポリテトラフルオロエチレン、ポリクロロトリフルオロエチレン、ポリビニルピロリドン、ポリメタクリル酸メチル、メタクリル酸メチル・スチレン共重合体、ポリメタクリル酸ブチル、ナイロン６６、エポキシ樹脂、ブタジエン・スチレン樹脂、ポリスルホン、ポリフッ化ビニリデン、ＭＢＳ樹脂、ポリブタジエン、ポリエーテルスルホンなどの各種物質やこれらの混合物を挙げることができる。
これらのうち、より好ましいものとしては、スチレン樹脂（ポリスチレン）、ポリビニルアルコール、アクリル樹脂（ポリアクリル酸）、シリコーン樹脂（ケイ素樹脂）、ポリメタクリル酸メチル、メタクリル酸メチル・アクリル酸エチル・スチレン共重合体、メタクリル酸メチル・スチレン共重合体、ポリメタクリル酸メチルブチル等を挙げることができる。より好ましいものとしては、スチレン樹脂、アクリル樹脂、シリコーン樹脂、メタクリル酸メチル・アクリル酸エチル・スチレン共重合体等を挙げることができる。特に好ましいものとしては、スチレン樹脂、アクリル樹脂、又はシリコーン樹脂を挙げることができる。
このような被膜材料を用いて所定の可視光線透過率、日射熱吸収率及び放射熱吸収率を有する被膜を形成する方法は特に限定されないが、例えば、上記被膜材料を溶剤により希釈して一定濃度の溶液を作成し、所望の被膜を得ることができる。
ここで用いられる好ましい溶剤としては、酢酸エチル、トルエン、キシレン、アセトン、シンナー等が挙げられる。これらの溶剤を用いて所定の被膜を得るためには、濃度０．０１〜１０％程度とするのが好ましい。
▲３▼被膜の厚み
本発明の被膜の厚みは特に限定されるものではないが、ランバート・ベールの法則によると、光を吸収する材料の厚さを大きくすると熱吸収量が増加し、小さくすると熱吸収量は減少する傾向にあることから、本発明においても、その被膜の厚みをある程度薄くすることにより熱吸収を減らし、可視光線透過率を大きくし、日射熱吸収率、常温熱放射の波長域における放射熱吸収率を小さくすることができる。
したがって、本発明の被膜の厚みとしては、好ましくは下限が０．０１μｍ、より好ましくは０．０２μｍ、さらに好ましくは０．０４μｍ、特に好ましくは０．１μｍであり、上限が１０μｍ、より好ましくは５μｍである。被膜が厚すぎると可視光線透過率が低下するのみならず、熱吸収量が増加し、日射熱吸収率及び放射熱吸収率が大きくなる傾向にある。一方、被膜の厚みは薄すぎると、ガラス基板からの剥離が起きやすくなる場合がある。
▲４▼放射熱吸収率の測定方法
本発明の日射熱遮断ガラスにおける、被膜の常温熱放射の波長域における放射熱吸収率の測定方法を示す。
ＪＩＳ−Ｒ−３１０６の常温熱放射の波長域における測定に準拠して、一般の化学分析用の赤外分光光度計を用い、アルミニウム板の上に被膜を形成してＪＩＳ−Ｒ−３１０６の標準反射率の値を用いて反射率を測定した。そして、灰色体の吸収率αと反射率ρと透過率τの間に関係式「α＋ρ＋τ＝１」が成り立つことに基づいて、吸収率αを「吸収率α＝１−（反射率ρ＋透過率τ）」により求めた。なお、透過率については、アルミニウム板の反射率とアルミニウム板に被膜を形成したときの反射率とを求めて、その差を被膜の透過率とした。
また、アルミニウム板の上に形成されたときの被膜の放射熱吸収は、放射熱の入射したときと反射して出るときの２回生じるので、吸収率αは、測定値の１／２とした。この数値を理論値として用い、ガラス表面およびポリエステルフィルム表面に形成した被膜の常温熱放射の波長域における放射熱吸収率とした。また、被膜の表面に生じる反射は０として計算した数値を用いた。
可視光線透過率及び日射熱吸収率は、ＪＩＳ−Ｒ−３１０６によりガラスとガラスに被膜を形成した状態で測定し、その差を被膜の可視光線透過率及び日射熱吸収率とした。
（３）日射熱遮断ガラス
次に添付図面に従って、本発明の日射熱遮断ガラスについて説明する。
図１は、本発明の日射熱遮断ガラスの一例の構造を示す断面図であって、ガラス基板１の片面に、可視光線透過率がガラス基板のそれより大きく（好ましくは９０％以上、より好ましくは９２％以上）、且つ日射熱吸収率及び常温熱放射の波長域における放射熱吸収率が共にガラス基板のそれより小さい（好ましくは日射熱吸収率が０．０１〜１１％、及び常温熱放射の波長域における放射熱吸収率が０．０１〜２０％の）被膜２が設けられている。なお、図１中、Ａは日射熱の照射される側であり、Ｂは閉鎖空間の内部側に相当する。
本発明の日射熱遮断ガラスの形状には特に制限はなく、方形状、円形状、筒状、半球状、球状など任意の形状に形成できるし、また、波形表面、凸凹表面、突起状表面などの表面形状に加工されたガラスでもよい。
ガラス基板上に被膜を形成して本発明の日射熱遮断ガラスを製造する方法としては、上述した被膜材料をあらかじめフィルム状又はシート状に形成し、それを熱融着や接着、粘着などにより貼着する方法、被膜材料を適当な溶剤に溶かして慣用されている方法により塗布し、乾燥、固化させる方法など、他の材料への積層に慣用されている方法の中から任意に選択することができる。また、被膜材料を分散、溶解などのこれまで慣用されている方法により処理した後、上記と同様の方法を用いて被覆することもできる。
なお、図１に示した日射熱遮断ガラスの一例は、ガラス基板及び被膜が各々単層の場合の例であるが、本発明においては、ガラス基板及び被膜の一方あるいは両者をさらに多層に構成した複合体とすることもできる。この場合においては、被膜層のうち、閉鎖空間内部側の空気層に接する層（最内層）の可視光線透過率がガラス基板のそれより大きく（好ましくは９０％以上）、且つ日射熱吸収率及び常温熱放射の波長域における放射熱吸収率が共にガラス基板のそれより小さく（好ましくは日射熱吸収率が０．０１〜１１％、常温熱放射の波長域における放射熱吸収率が０．０１〜２０％）なるように、被膜を形成するのが望ましい。
本発明の日射熱遮断ガラスは、構築物や建物、車両などの窓ガラスとして用いることができるほか、従来からある構築物や建物、車両などの窓ガラスに後から被膜を形成することもできる。また、本発明の日射熱遮断ガラスは、従来の熱線吸収ガラスや熱線反射ガラスと併用することもできる。
このような本発明の日射熱遮断ガラスは、具体的には、住宅、保冷倉庫、天井、壁、車両、各種容器などの窓ガラスやガラス建材として効果的に利用することができる。
なお、高温となったガラスからの熱放射を小さくさせるには、反射率が大きく吸収率の小さい金属やセラミックスなどを、ガラス面に被覆して放射熱吸収率を小さくさせることもできるので、従来の技術による製品でも結果的に高温となったガラスからの放射を低減することは可能であるが、可視光線も反射するので内部が暗くなってしまう。また、反射率の大きい金属層の配置を外気側にするとガラスに吸収された熱は中に多く入射して、内部の熱負荷は増加する。そして、金属層を多層系の中央に配置すると低放射面が閉鎖空間の内部側に配置されないので、やはり内部の熱負荷は低減されず、本発明の効果を得ることはできない。
つまり、本発明のように、建物や車両などの窓ガラスの内側に放射熱吸収率の小さいプラスチックス等の被膜を形成させることにより、ガラス本来の可視光線の透明度を損なわずに、高温となったガラスからの常温熱放射だけを遮断させ、室内や車内の日射による熱負荷を低減させることを可能にした日射熱遮断ガラスはない。
２．日射熱遮断方法
本発明の日射熱遮断方法は、上述した本発明の日射熱遮断ガラスを、ガラス基板面が日射熱の照射される側に向くように配置して（日射熱を吸収し）、前記被膜面側からの熱放射を遮断することを特徴とする方法である。すなわち、日射熱遮断ガラスの、可視光線透過率がガラス基板のそれより大きく（好ましくは９０％以上）、且つ日射熱吸収率及び常温熱放射の波長域における放射熱吸収率が共にガラス基板のそれより小さい（好ましくは日射熱吸収率が０．０１〜１１％、常温熱放射の波長域における放射熱吸収率が０．０１〜２０％）被膜の形成された面を、建物や車両などの閉鎖空間の内部側に向けて配置する。これにより、内部を暗くすることなく、日射を吸収して高温となったガラスから内部への熱放射を効果的に遮断することができる。
また、従来からある構築物や建物、車両などの窓ガラスの、室内又は車内等の閉鎖空間内部側の側面に、上記被膜を形成することによっても、高温となったガラスからの常温熱放射を遮断させ、室内や車内の日射による熱負荷を低減させることができる。
発明を実施するための最良の形態
以下に、実施例を挙げて本発明を具体的に説明するが、本発明はこれらの実施例にのみ限定されるものではない。
実施例１
メタクリル酸メチル−アクリル酸エチル−スチレン共重合体を酢酸エチルにより希釈して濃度の異なる溶液（各濃度；試料１＝０．１重量％、試料２＝５．０重量％、試料３＝５．０重量％、試料４＝５．０重量％、試料５＝１０．０重量％、試料６＝１５．０重量％）を作成した。そして、各試料の日射熱吸収率及び常温熱放射の波長域における放射熱吸収率は、着色剤と赤外線吸収剤を各試料について以下に示すように処方することによって調整した。
試料１・２＝着色剤・赤外線吸収剤の混合なし
試料３＝着色剤を添加（全体の溶液濃度：０．０００１重量％）
試料４＝着色剤及び赤外線吸収剤を添加（全体の溶液濃度：着色剤；０．０００２重量％、赤外線吸収剤；０．０００５重量％）
試料５＝着色剤及び赤外線吸収剤を添加（全体の溶液濃度：着色剤；０．００１重量％、赤外線吸収剤；０．００１重量％）
試料６＝着色剤及び赤外線吸収剤を添加（全体の溶液濃度：着色剤；０．０１重量％、赤外線吸収剤；０．０１重量％）
ここで、着色剤としては「ＲＥＤ ＢＷ」（日本化薬（株）製）０．０１重量％と、「Ｕｌｔｒａ Ｓｋｙ ＳＥ」（日本化薬（株）製）０．０１重量％とを酢酸エチルに溶解した混合溶液を用いた。また、赤外線吸収剤としては、「エポライト２０５７」の１．０重量％溶液（溶剤；ＭＥＫ・ＩＰＡ・酢酸エチル・トルエンの混合溶剤）を使用した。
この溶液を、流し塗りの方法を用いて縦５０ｃｍ、横５０ｃｍの同一のガラス板の片面に塗布し、被膜を形成した。このときの常温熱放射の波長域における吸収率の値は、前記に示した理論値を用いた。ここで、ガラス板の厚みは５ｍｍである。また、被膜の厚みは、試料１＝０．０４μｍ、試料２＝３．２μｍ、試料３＝３．７μｍ、試料４＝３．９μｍ、試料５＝５．５μｍ、試料６＝８．９μｍである。
なお、被膜の厚みの測定は次の方法で行った。上記ガラス板（縦０．５ｍ×横０．５ｍで面積が０．２５ｍ２）に各試料の液剤（例えば濃度０．１重量％の試料１溶液）を流し塗りによりコーティングした際、流れ落ちた液剤の重量を計測し、減少した液剤分をガラスに付着した分としてその固形分重量を計算で求め、「固形分重量÷ガラスの面積」を膜厚とし、この数値を膜厚の理論値として用いた。他の試料についても同様である。
次に、厚さ５ｍｍの発泡スチロール板で一面のみを開放した立方体の箱（５０×５０×５０ｃｍ）７個を作成し、その箱の開口部に被覆していないガラス板及び被覆したガラス板を被膜面が中側になるように配置して取り付けた。
被覆したガラス板及び被覆していないガラス板を取り付けた開口部を上に向けて、２０℃に設定された室内に置き、ガラスの上５０ｃｍから６０Ｗ−赤外線ランプで箱の中の温度が平衡になるまで加熱し、そのときの箱の中の温度を測定した。結果を表１に示す。
一方、試料４〜６（比較例）の場合は、被膜の常温熱放射の波長域における放射熱吸収率はガラス板より小さいが、日射熱吸収率はガラス板より大きい。被膜の日射熱吸収率がガラスより大きくなると、ガラスを透過した日射熱が、ガラスだけの場合より被膜に多く吸収され、その熱が外気側に放熱されるときガラスが放熱を阻害するため被膜に吸収された熱のほとんどは箱内に入る。
通常、ガラスに吸収された熱は閉鎖空間内に入る熱と外気に出る熱があり、閉鎖空間内（箱内）の温度はガラスを透過して直接中に入る熱と日射熱を吸収して高温となったガラスから中に入る熱の合計によって決まる。試料４〜６の場合、ガラスを透過して直接中に入る熱は減少したが、被膜に吸収された熱はガラスが阻害して外気に殆ど放熱されず、被膜に吸収された熱の殆どが箱内に入ったため、ガラスを透過して直接入る熱と日射熱を吸収して高温となったガラス及び被膜から箱内に入る熱の合計が大きくなり、ガラスだけの場合より箱内の温度が高くなったと考えられる。すなわち、被膜の日射熱吸収率がガラス板より大きい試料４〜６は、その常温熱放射の波長域における放射熱吸収率がガラスより小さくても箱内の温度がガラスだけの場合より高くなったものである。
実施例２
実施例１で用いたものと同様の、被覆していないガラス板及び被覆したガラス板を被膜面が中側になるように配置した厚さ５ｍｍの発泡スチロールの箱（５０×５０×５０ｃｍ）を用意した。
被覆したガラス板及び被覆していないガラス板を取り付けた開口部を上に向けて、太陽光線の良く当たる広い場所に設置し、太陽光線を照射したときの箱の中が平衡になったときの温度を測定した。被膜の可視光線透過率、日射熱吸収率及び常温熱放射の波長域における吸収率は、実施例１と同じく理論値を用いた。このときの外気温は３４．６℃であった。この結果を表２に示す。
一方、被膜の常温熱放射の波長域における放射熱吸収率はガラス板より小さいが、日射熱吸収率はガラス板より大きい試料４〜６（比較例）の場合は、ガラスを透過して直接中に入る熱は減少したが、被膜に吸収された熱はガラスが阻害して外気に殆ど放熱されず、被膜に吸収された熱の殆どが箱内に入ったため、ガラスを透過して直接入る熱と日射熱を吸収して高温となったガラス及び被膜から箱内に入る熱の合計が大きくなり、ガラスだけの場合より箱内の温度が高くなったと考えられる。
実施例３
鉄筋コンクリート造９階建の建物の８階部分において、容積が５５ｍ３であって、東向きの壁に厚さ５ｍｍの窓ガラスをはめた縦１．５ｍ、横２．８ｍの長方形の窓がある隣り合わせた同一の部屋３個を用意し、その窓ガラスの室内側に、１つの部屋のガラス窓には実施例１で作成した日射熱吸収率０．０９％で常温熱放射の波長域における放射熱吸収率（理論値）が０．４８％となる塗料を流し塗りの方法を用いて塗布し、被膜（厚さ；０．０４μｍ）を形成した（試料１）。
そして、もう１つの部屋の窓ガラスには、ガラスに貼着する側に粘着層を設けたポリエステルフィルムであって、その該粘着層と反対の側に、上と同様に日射熱吸収率が０．０９％で常温熱放射の波長域における吸収率（理論値）が０．４８％となる液を塗布したもの（塗布層の厚さ；０．０７μｍ、フィルムの厚さ；５０μｍ、粘着層の厚さ；２０μｍ）を、室内側に貼った（試料２）。そして、もう１つの部屋は窓ガラスのみとした（試料３）。
窓ガラスに被膜を形成した部屋（試料１）とポリエステルフィルムを貼った部屋（試料２）と窓ガラスのみの部屋（試料３）において、太陽光線が照射されたときの室内の窓際から１ｍ離れた地点での経時的な温度変化を測定した。被膜の日射熱吸収率及び放射熱吸収率は、実施例１と同じく理論値を用いた。この結果を表３に示す。なお、表中の数値の単位は℃である。
実施例４
実施例１で用いたものと同じ厚さ５ｍｍの発泡スチロール板で一面のみを開放した立方体の箱（５０×５０×５０ｃｍ）７個を作成し用意した。
粘着層を２５μｍ設けた厚さ５０μｍのポリエステルフィルムの粘着層とは反対側の面に、実施例１で用いたのと同じ塗料を流し塗りの方法で塗布し、被膜を形成した。
このフィルムを、粘着層を介して厚さ５ｍｍのガラス板に貼り（被膜を形成していないポリエステルフィルムのみを貼ったものも用意した）、フィルムの被膜形成面が箱の中側になるように配置した。太陽光線の良く当たる広い場所にガラス面を上に向けて設置し、太陽光線を照射したときの箱の中が平衡になったときの温度を測定した。このときの外気温は３４．９℃であった。被膜の日射熱吸収率及び常温熱放射の波長域における放射熱吸収率は、実施例１と同じく理論値を用いた。その結果を表４に示す。
太陽光線を照射したときの箱内の最高温度は、被膜の日射熱吸収率及び常温熱放射の波長域における吸収率が共にポリエステルフィルムのみを貼ったガラス板のそれより小さいときに、箱内の最高温度が、ポリエステルフィルムのみを貼ったガラス板の場合より０．１〜２．０℃低くなり、発泡スチロール製の箱の開口部に取り付けたガラスの中側表面からの放射熱が減少し、外部へ多く放熱したことが分かる。
一方、被膜の常温熱放射の波長域における放射熱吸収率はポリエステルフィルムのみを貼ったガラス板より小さいが、日射熱吸収率はポリエステルフィルムのみを貼ったガラス板より大きい試料４〜６（比較例）の場合は、ガラスを透過して直接中に入る熱は減少したが、被膜に吸収された熱はガラスが阻害して外気に殆ど放熱されず、被膜に吸収された熱の殆どが箱内に入ったため、ガラスを透過して直接入る熱と日射熱を吸収して高温となったガラス及び被膜から箱内に入る熱の合計が大きくなり、ガラスだけの場合より箱内の温度が高くなったと考えられる。
実施例５
実施例１で用いたものと同じ厚さ５ｍｍの発泡スチロール板で一面のみを開放した立方体の箱（５０×５０×５０ｃｍ）７個を作成し用意した。
そして、日射熱吸収率が３３．６％の熱線吸収ガラスに、実施例１で作成した塗料を実施例１と同じ方法で塗布した。
次に、実施例１と同様に被膜面が箱の中側になるように、熱線吸収ガラスを箱に配置して、ガラス面を上に向けて設置した。そして、太陽光線の良く当たる広い場所に設置し、太陽光線を照射したときの箱の中が平衡になったときの温度を測定した。このときの外気温は３３．２℃であった。その結果を表５に示す。
産業上の利用可能性
本発明の日射熱遮断ガラスは、ガラス基板の片面に可視光線帯域の透過率が大きく日射熱吸収率及び常温熱放射の波長域の吸収率が小さい被膜を形成したものである。この日射熱遮断ガラスからなるガラス窓を、被膜面が建物や車両などの閉鎖空間の内部側（室内又は車内側）に向くように設置することにより、ガラス面が日射により加熱されて温度上昇したのちに生じるガラスからの熱放射が内部に入射することを阻止して、外気側に多く放射させ、室内等の熱負荷を低減させることができる。
また、ガラス本来の可視光線の透明度を損なうことがないため、室内や車内を暗くすることなく、中の温度上昇を抑えることができる。さらに、従来の金属やセラミックスを用いたものと異なり、簡便に製造することができ、安価である。よって、住宅、保冷倉庫、天井、壁、車両、各種容器などの窓ガラスやガラス建材等として効果的に利用することができる。
【図面の簡単な説明】
図１は本発明の日射熱遮断ガラスの構造を示す断面図である。図２は本発明の実施例３における室内の経時的な温度変化を表すグラフである。
図１中、１はガラス基板、２は被膜、Ａは日射熱の照射される側、Ｂは閉鎖空間内を示す。図２中、ａは試料１、ｂは試料２、ｃは試料３を示す。 Technical field
The present invention relates to a novel solar heat-shielding glass in which a glass substrate is provided with a film having a small thermal radiation in the wavelength range of room temperature thermal radiation. Specifically, the present invention is a solar heat shield that can block solar heat radiation by blocking heat radiation (heat radiation in the wavelength region of room temperature heat radiation) from a glass surface heated by solar radiation to increase its temperature. The present invention relates to glass and a method for shielding solar heat using the same.
Background art
In general, in a building or vehicle with a closed space with a glass window, the glass surface is heated by solar radiation and becomes high temperature, and the solar heat absorbed by the glass is radiated inside the enclosed space such as indoors and cars. As a result, the internal temperature rises, which may cause various problems such as deterioration of the effectiveness of the air conditioner particularly in summer.
In order to block such radiation of solar heat, heat ray absorbing glass that absorbs solar radiation using various inorganic or organic substances and heat ray reflecting glass that reflects solar radiation have been developed. However, in order to block the solar heat that passes through the glass and directly enters the enclosed space, they use organic or inorganic materials that absorb the solar heat itself, or use metals or inorganic materials that reflect the solar heat. Is.
In heat ray absorbing glass or heat ray reflecting glass that directly absorbs or reflects such solar heat, there is a method of increasing the material that absorbs or reflects solar heat in order to enhance the solar heat blocking effect. However, there are practical disadvantages such as an increase in cost or a decrease in transparency in the visible light band, resulting in a dark interior.
In addition, the glass that absorbs solar heat has a drawback in that the heat absorbed in the glass is radiated to the inside again after a long time, so that the reduction of the heat load inside the enclosed space cannot be greatly expected.
On the other hand, glass that reflects solar radiation hardly absorbs wavelengths in the wavelength range of room temperature thermal radiation, so it does not cause re-radiation, but these also use metals and ceramics that reflect infrared rays. In addition, there was a drawback that the visible light was reflected and the inside became dark.
In order to solve these problems, the metal layer is arranged in the center, and the refractive index is adjusted by forming the metal cover layers on both sides thereof, the visible light transmittance is increased to about 70%, and the glass layer is adhered to the glass. SnO as a multilayer heat insulating material (Japanese Patent Laid-Open No. Sho 59-103749) that reflects infrared rays and a low radiation film that reduces radiation2: Sn film to reduce color unevenness using F film2Film and SiO2There are a low-emission glass in which a film is laminated in the middle of a glass substrate and a glass article using the low-emission glass (Japanese Patent Laid-Open No. 2001-2449), but the transparency in the visible light band is still not sufficient.
Moreover, in order to produce these glasses and films, it is necessary to use an apparatus such as vacuum deposition or sputtering in order to coat the glass with metal or ceramics, which is disadvantageous economically.
For these reasons, an inexpensive solar heat insulation glass that has high transparency in the visible light band and that can reduce the heat load due to solar radiation has been awaited.
Disclosure of the invention
As described above, in the market today, it has been desired to provide a glass that can reduce the thermal load caused by solar radiation in summer and the like at low cost without impairing the transmission of visible light inherent to the glass. In particular, there has been a great demand for vehicles that require transparency in the visible light band.
However, the above-mentioned prior art has to sacrifice visible light transmission in order to reduce the heat load caused by solar radiation, and it is possible to produce an inexpensive window glass with high transparency in the visible light band that meets today's market needs. I can't get it.
An object of the present invention is to solve such a problem and to provide an inexpensive solar heat insulation glass capable of reducing the heat load caused by solar radiation without impairing the transparency of visible light inherent to the glass.
As a result of intensive studies in view of the above-mentioned problems, the present inventors have formed a coating on one surface of a glass substrate so that the visible light transmittance is large and the solar heat absorption rate and the radiant heat absorption rate in the wavelength range of room temperature thermal radiation are low. Wavelength of room temperature thermal radiation from a glass substrate that has become hot due to absorption of solar radiation by using the formed composite glass and placing the coating surface inside the enclosed space, that is, the interior of a building or vehicle, etc. It was found that the heat radiation in the area can be effectively cut off and the heat load inside the enclosed space can be reduced, and the present invention has been completed.
That is, this invention relates to the solar heat insulation glass shown to the following (1)-(5), and the solar heat insulation method using the same.
(1) On one surface of a glass substrate, the visible light transmittance is larger than the visible light transmittance of the glass substrate, and both the solar heat absorption rate and the radiation heat absorption rate in the wavelength region of room temperature thermal radiation are the solar heat of the glass substrate. A solar heat-shielding glass, characterized in that a coating smaller than the absorptivity and the radiant heat absorptivity in the wavelength range of room temperature thermal radiation is provided.
(2) The visible light transmittance of the coating is 90% or more, the solar heat absorption rate is 0.01 to 11%, and the radiant heat absorption rate in the wavelength range of room temperature thermal radiation is 0.01 to 20%. The solar heat insulation glass according to (1), characterized in that
(3) The solar radiation heat-shielding glass according to (1) or (2), wherein the wavelength range of room temperature thermal radiation in the radiant heat absorption rate is 5 to 50 μm.
(4) The solar-heat-shielding glass according to any one of (1) to (3), wherein the material forming the film is a plastic selected from the group consisting of an acrylic resin, a silicone resin, and a styrene resin.
(5) The solar radiation shielding glass according to any one of (1) to (4) is disposed so that the glass substrate surface faces the side irradiated with solar heat, and heat radiation from the coating surface side A method for blocking solar heat, characterized by blocking the sun.
Glass absorbs irradiation heat such as solar heat irradiated from sunlight. Here, although the wavelength range of sunlight is 0.3 μm to 3.0 μm, not only the absorption of an infrared band of 2.5 μm or more in general transparent plate glass but also visible light of 2.5 μm or less, Absorbs near infrared rays. And the temperature of glass rises by the absorption of the solar radiation heat, and the heat absorbed by the glass is radiated to the indoor side or the outside air by convection and radiation.
Here, convection heat transfer is relatively small because air convection in a closed space such as a room or a car is small. On the other hand, the heat transfer by radiation is a direct heat transfer between the glass and the object or air in the glass, and is hardly affected by air convection. In other words, the heat incident on the inside of the space from the glass that has reached a high temperature has a higher rate of heat transfer by radiation in the closed space.
Further, the solar heat absorbed by the glass increases as the glass thickness increases, and becomes about 6% or more even in 3 mm glass. And the thermal radiation from glass becomes a big heat load in closed space. Therefore, it is considered that the heat load in the closed space can be reduced if the solar heat absorbed by the glass is prevented from entering the closed space by re-radiation and radiated to the outside air.
The range of wavelengths irradiated from sunlight is 0.3 μm to 3.0 μm, but the range of wavelengths emitted from glass whose temperature has been increased by absorbing solar heat is 5 μm to 50 μm. This is the wavelength region. Therefore, in order to prevent the heat absorbed by the glass from entering the inside of the closed space by radiation, it is only necessary to block the heat radiation in the wavelength range of at least 5 μm to 50 μm.
Heat transferred from the solid to the air is transferred through the solid by conduction, and from the solid surface to the air by convection and radiation. Therefore, in order to block the thermal radiation from the glass, the emissivity on the glass surface may be reduced. That is, the absorption rate in the wavelength region of normal temperature thermal radiation on the glass surface may be reduced. That is, a film made of an object having a low absorption rate in the wavelength region of room temperature thermal radiation of 5 μm to 50 μm may be formed on the glass surface. And by arrange | positioning the surface in which this film was formed toward the inner side of closed space, the amount of radiant heat transfer between glass and the inside object reduces.
On the other hand, when the solar heat absorption rate of the coating itself formed on the glass surface is larger than that of glass, the solar heat transmitted through the glass is absorbed more in the coating than in the case of only glass, and when the heat is dissipated to the outside air, the glass Most of the heat absorbed by the coating is released to the inside of the enclosed space because it inhibits heat dissipation. That is, when the solar radiation heat absorption rate of the coating is larger than that of glass, the temperature in the enclosed space becomes high even if the radiation heat absorption rate in the wavelength region of room temperature thermal radiation is smaller than that of glass. Therefore, it can be seen that not only the radiant heat absorption rate in the radiation wavelength region of the coating but also the solar heat absorption rate is related to the amount of radiant heat transfer from the glass into the enclosed space.
In general, unlike inorganic materials, organic materials have low absorption and reflection in the visible light band and infrared band and large transmission. Therefore, if a coating made of plastics with low absorption and reflection in the infrared band and high transmission is formed on one side of the glass and the coating is placed facing the inside of the enclosed space, the visible light transmittance of the glass is almost reduced. It is thought that the thermal load inside the space can be reduced without conducting the experiment, and the present invention has been completed by finding the relationship between the visible light transmittance of the coating, the solar heat absorptivity, and the wavelength region absorptivity of room temperature thermal radiation through experiments. .
Hereinafter, the present invention will be described in detail.
1. Solar heat insulation glass
The solar heat insulation glass of the present invention is a glass substrate provided with a specific coating on one side.
(1) Glass substrate
There is no restriction | limiting in particular in the kind of glass used for a glass substrate by this invention, Not only transparent plate glass but heat ray absorption glass, heat ray reflective glass, etc. may be sufficient. Any effect of the present invention can be exhibited as long as it has a property capable of radiating solar heat absorbed by solar radiation.
Heat ray absorbing glass, heat ray reflecting glass, and the like can further prevent direct incident solar radiation and also prevent thermal radiation from glass that has become high temperature by absorbing solar radiation by forming the coating film of the present invention on one side. Therefore, the effect of reducing the thermal load of the present invention is further improved.
Although there is no restriction | limiting in particular also about the thickness of a glass substrate, Preferably it is 0.1-20 mm, More preferably, it is 1-20 mm. Even if the material of the glass is the same, the greater the thickness, the greater the solar heat absorption rate and the greater the heat radiation from the glass, so the effect of blocking the heat radiation from the glass becomes greater.
(2) Coating
The coating provided on one side of the glass substrate in the present invention has a visible light transmittance larger than that of the glass substrate, and both the solar heat absorption rate and the radiation heat absorption rate in the wavelength region of room temperature thermal radiation are those of the glass substrate. It is a small one.
(1) Visible light transmittance, solar heat absorption rate and radiant heat absorption rate
Here, the relationship between the amount of radiant heat transfer and the visible light transmittance, solar heat absorption rate, and radiant heat absorption rate of a substance will be described below.
<Relationship between radiant heat transfer and emissivity of objects>
The radiant heat Q in the radiant heat transfer is expressed by the following equation, which can be transferred even in a vacuum.
Q = σ · ε · (T / 100)4
Where σ is the Stefan-Boltzmann constant, ε is the emissivity of the object, and T is the absolute temperature of the object. As is clear from this equation, if the emissivity is reduced, the amount of heat radiated from the object is reduced.
In addition, the amount of heat transfer Q by radiant heat transfer (radiant heat transfer) transmitted from the object surface to the object such as a fluid in a low temperature zone.2Is expressed as follows.
Q2= Σ × f (ε) × [(Tr/ 100)4-(T0/ 100)4]
Where σ is the Stefan-Boltzmann constant, f (ε) is the radiation coefficient of radiant heat transfer between objects, and TrIs the surface temperature of the object (K), T0Is the surface temperature (K) of the object in the low temperature zone.
As is apparent from this equation, if the radiation coefficient of radiant heat transfer between the object surfaces is reduced, the amount of radiant heat transfer between the objects decreases.
The radiation heat transfer coefficient is expressed by the following formula.
f (ε) = 1 / (1 / ε1) + (1 / ε2-1
Where ε1= Emissivity of substances on the high temperature zone side, ε2= Emissivity of materials on the low temperature zone side.
Therefore, if one emissivity between the objects is reduced, the radiant heat transfer coefficient f (ε) is reduced and the radiant heat transfer amount is reduced.
That is, if there is the same object on both sides of the glass, heat transfer by radiation from the glass surface will be the same. Therefore, when a film made of a substance having a low emissivity is formed on one surface of glass, the emissivity of the surface on which the film is formed becomes small. It decreases with respect to the amount of radiant heat transfer from the unformed glass surface.
In other words, when a film made of a substance with a low emissivity is formed on the indoor surface of a window glass provided in a closed building or vehicle, the indoor surface of the glass heated to the sun and the indoor (closed) The amount of radiant heat transfer between a substance such as air in the space) and an internal object is reduced, and a large amount of heat absorbed by the glass is radiated to the outside air, so that the internal heat load is reduced.
<Relationship between emissivity and radiant heat absorption rate of objects>
Normally, an object such as metal absorbs part of solar heat and the like and reflects all of the other, so the following relational expression “α + ρ = 1” holds between the absorption rate α and the reflection rate ρ, and visible light It can be seen that it does not transmit in the infrared band. However, an object such as glass or plastic is a gray body that partially absorbs solar heat, partially reflects, and further partially transmits. In the case of such a gray body, the following relational expression “α + ρ + τ = 1” is established between the absorptance α, the reflectance ρ, and the transmittance τ, and it can be seen that there is radiant heat that is transmitted in the visible light and infrared bands. .
According to Kirchhoff's law, the absorption rate and emissivity of such heat are equal, so in order to block radiant heat from glass that has become hot due to solar radiation, the wavelength range of thermal radiation from such glass, that is, room temperature A substance having a large transmission and a low radiant heat absorption rate (radiant heat absorption rate) may be selected in the wavelength range of thermal radiation. At this time, the wavelength range of normal temperature thermal radiation is in the range of 5 to 50 μm.
That is, if a material such as plastics having a low radiant heat absorption rate is selected in the wavelength range of 5 to 50 μm and a film is formed on the glass surface, the amount of radiant heat transfer from the surface of the film decreases.
Thus, the film used in the solar heat shielding glass of the present invention has a visible light transmittance greater than the visible light transmittance of the glass substrate, and the solar heat absorption rate is smaller than the solar heat absorption rate of the glass substrate, Furthermore, the radiant heat absorption rate in the wavelength region of the room temperature thermal radiation is smaller than the radiant heat absorption rate in the wavelength region of the room temperature thermal radiation of the glass substrate. Preferably, the visible light transmittance is 90% or more, the solar heat absorptivity is 0.01 to 11%, and the radiant heat absorptivity in the wavelength region of room temperature thermal radiation is 0.01 to 20%. More preferably, the visible light transmittance is 92% or more, the solar heat absorptivity is 0.09 to 11%, and the radiant heat absorptivity in the wavelength range of room temperature thermal radiation is 0.48 to 17%.
If the visible light transmittance is smaller than the above range, a solar heat shielding glass with a high transparency cannot be obtained. Moreover, if the solar heat absorption rate and the radiant heat absorption rate are higher than the above ranges, the heat radiation to the inside of the enclosed space cannot be efficiently blocked, and the effect of the present invention for reducing the internal heat load is sufficiently exhibited. Not.
(2) Coating material
In general, materials such as metals and ceramics with high reflectivity are reflected in the same way in the visible light band and the wavelength range of room temperature thermal radiation. If it is attempted to decrease the reflectance, the reflectance in the visible light band increases and the transparency decreases. However, in general, gray bodies such as plastics are substances that have a high transmittance in the visible light band and a wavelength region in room temperature thermal radiation and a low absorption rate.
According to Lambert-Beer's law, the thinner the material, the greater the transmittance. That is, when a gray body such as plastic is formed thinly and coated so as to increase the transmittance in the wavelength region of room temperature thermal radiation so as to reduce the absorption, the visible light transmittance of the coating also increases. Therefore, even if a thin gray film such as plastics is formed on one side of the glass, the transmittance in the visible light band of the glass is hardly reduced, and the original transparency of the glass is not impaired.
And when the thin film surface is arranged toward a closed space, that is, the interior (indoor or interior) of a building or a vehicle, the transparency is high and the heat absorbed by the glass is not incident on the interior. It is possible to obtain a solar heat insulation glass that radiates a lot to the outside air and reduces the internal heat load.
Thus, as the material for the coating of the present invention, it is preferable to use a substance having a high visible light transmittance and a low solar heat absorption rate and a low radiant heat absorption rate in the wavelength region of room temperature thermal radiation.
Accordingly, the coating material is not particularly limited as long as the above conditions are satisfied, but preferably plastics such as polyethylene, polypropylene, polyisobutylene, polystyrene, polyvinyl acetate, ethylene / vinyl acetate copolymer, polyvinyl alcohol, Polyvinyl chloride, vinyl chloride / vinylidene chloride copolymer, polyacrylonitrile, polyvinyl pyrrolidone, polyacrylic acid, polymethyl methacrylate, methyl methacrylate / styrene copolymer, polybutyl methacrylate, silicon resin, butadiene rubber, butyl rubber, Chloroprene rubber, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, cellulose acetate, diallyl phthalate resin, urea resin, melamine resin, polyvinyl butyral, vinyl chloride / acetic acid Nyl copolymer, ethylene / α-olefin copolymer, ethylene / vinyl chloride copolymer, acrylic acid / vinyl chloride copolymer, polymethylpentene, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylpyrrolidone, poly Various substances such as methyl methacrylate, methyl methacrylate / styrene copolymer, polybutyl methacrylate, nylon 66, epoxy resin, butadiene / styrene resin, polysulfone, polyvinylidene fluoride, MBS resin, polybutadiene, polyethersulfone and the like Mention may be made of mixtures.
Of these, more preferred are styrene resin (polystyrene), polyvinyl alcohol, acrylic resin (polyacrylic acid), silicone resin (silicon resin), polymethyl methacrylate, methyl methacrylate / ethyl acrylate / styrene copolymer Examples of the polymer include methyl methacrylate / styrene copolymer and polymethylbutyl methacrylate. More preferable examples include styrene resin, acrylic resin, silicone resin, methyl methacrylate / ethyl acrylate / styrene copolymer, and the like. Particularly preferable examples include styrene resin, acrylic resin, and silicone resin.
A method for forming a film having a predetermined visible light transmittance, solar heat absorption rate, and radiant heat absorption rate using such a film material is not particularly limited. For example, the film material is diluted with a solvent to have a constant concentration. A desired film can be obtained by preparing a solution of
Preferred solvents used here include ethyl acetate, toluene, xylene, acetone, thinner and the like. In order to obtain a predetermined film using these solvents, the concentration is preferably about 0.01 to 10%.
(3) Film thickness
The thickness of the coating of the present invention is not particularly limited, but according to Lambert-Beer's law, increasing the thickness of the material that absorbs light increases the heat absorption, and decreasing it reduces the heat absorption. Because of this tendency, the present invention also reduces the heat absorption by increasing the thickness of the coating to some extent, increases the visible light transmittance, increases the solar heat absorption rate, and the radiation heat absorption rate in the wavelength range of room temperature thermal radiation. Can be reduced.
Accordingly, the thickness of the coating of the present invention is preferably 0.01 μm, more preferably 0.02 μm, still more preferably 0.04 μm, particularly preferably 0.1 μm, and the upper limit is 10 μm, more preferably 5 μm. It is. When the film is too thick, not only the visible light transmittance is lowered, but also the heat absorption amount is increased, and the solar heat absorption coefficient and the radiant heat absorption coefficient tend to be increased. On the other hand, if the thickness of the coating is too thin, peeling from the glass substrate may easily occur.
(4) Measuring method of radiant heat absorption rate
The measuring method of the radiant heat absorption factor in the wavelength range of the room temperature thermal radiation of the film in the solar heat insulation glass of the present invention is shown.
Based on the measurement in the wavelength range of room temperature thermal radiation of JIS-R-3106, using a general infrared spectrophotometer for chemical analysis, a film is formed on an aluminum plate, and the standard of JIS-R-3106 The reflectance was measured using the reflectance value. Based on the fact that the relational expression “α + ρ + τ = 1” holds among the absorption rate α, the reflectance ρ, and the transmittance τ of the gray body, the absorption rate α is changed to “absorption rate α = 1− (reflectance ρ + transmittance). τ) ”. In addition, about the transmittance | permeability, the reflectance of an aluminum plate and the reflectance when a film was formed in an aluminum plate were calculated | required, and the difference was made into the transmittance | permeability of a film.
In addition, since the radiant heat absorption of the coating when formed on the aluminum plate occurs twice when the radiant heat is incident and when it is reflected, the absorption rate α is ½ of the measured value. . This numerical value was used as a theoretical value, and was defined as the radiant heat absorption rate in the wavelength range of room temperature thermal radiation of the coating formed on the glass surface and the polyester film surface. Moreover, the numerical value computed as 0 was used for the reflection which arises on the surface of a film.
Visible light transmittance and solar heat absorption were measured in a state where a film was formed on glass and glass according to JIS-R-3106, and the difference was defined as the visible light transmittance and solar heat absorption of the film.
(3) Solar heat insulation glass
Next, the solar heat insulation glass of the present invention will be described with reference to the attached drawings.
FIG. 1 is a cross-sectional view showing the structure of an example of the solar heat-shielding glass of the present invention. On one side of the glass substrate 1, the visible light transmittance is larger than that of the glass substrate (preferably 90% or more, more preferably 92% or more), and both the solar heat absorption rate and the radiant heat absorption rate in the wavelength region of room temperature thermal radiation are smaller than those of the glass substrate (preferably the solar heat absorption rate is 0.01 to 11%, and room temperature thermal radiation.
The shape of the solar heat insulation glass of the present invention is not particularly limited, and can be formed in any shape such as a square shape, a circular shape, a cylindrical shape, a hemispherical shape, a spherical shape, and a corrugated surface, an uneven surface, a protruding surface, etc. Glass processed into the surface shape may be used.
As a method for producing the solar heat-shielding glass of the present invention by forming a film on a glass substrate, the above-mentioned film material is previously formed into a film shape or a sheet shape, and is pasted by heat fusion, adhesion, adhesion or the like. It is possible to arbitrarily select from methods commonly used for lamination to other materials, such as a method of applying, a method in which a coating material is dissolved in a suitable solvent, and a method of applying, drying and solidifying the coating material. it can. Further, after the coating material is treated by a conventionally used method such as dispersion or dissolution, it can be coated using the same method as described above.
In addition, although an example of the solar radiation shielding glass shown in FIG. 1 is an example in which each of the glass substrate and the coating film is a single layer, in the present invention, one or both of the glass substrate and the coating film are configured in multiple layers. It can also be a complex. In this case, among the coating layers, the visible light transmittance of the layer (innermost layer) in contact with the air layer on the inner side of the enclosed space is larger than that of the glass substrate (preferably 90% or more), and the solar heat absorption rate and Both the radiant heat absorption rate in the wavelength range of room temperature thermal radiation is smaller than that of the glass substrate (preferably the solar heat absorption rate is 0.01 to 11%, the radiant heat absorption rate in the wavelength range of room temperature thermal radiation is 0.01 to It is desirable to form a film so as to be 20%.
The solar heat insulation glass of the present invention can be used as a window glass for a structure, a building, a vehicle, or the like, and a film can be formed later on a window glass for a conventional structure, building, vehicle, or the like. Moreover, the solar heat insulation glass of this invention can also be used together with the conventional heat ray absorption glass and heat ray reflective glass.
Specifically, the solar heat insulation glass of the present invention can be effectively used as window glass and glass building materials for houses, cold storage, ceilings, walls, vehicles, various containers and the like.
In order to reduce the heat radiation from the glass that has become high temperature, it is possible to reduce the radiant heat absorption rate by coating the glass surface with metal or ceramics with high reflectivity and low absorption rate. Although it is possible to reduce the radiation from the glass having a high temperature as a result even with the product of this technique, the inside becomes dark because it reflects visible light. Further, when the arrangement of the metal layer having a high reflectance is arranged on the outside air side, a large amount of heat absorbed by the glass is incident on the inside, and the internal heat load increases. And if a metal layer is arrange | positioned in the center of a multilayer system, since a low radiation surface will not be arrange | positioned inside closed space, an internal thermal load will not be reduced, and the effect of this invention cannot be acquired.
That is, as in the present invention, by forming a film of plastics or the like having a low radiant heat absorption rate on the inside of a window glass of a building or a vehicle, the temperature becomes high without impairing the transparency of the visible light inherent to the glass. There is no solar heat blocking glass that can block only the room temperature heat radiation from the glass and reduce the heat load caused by solar radiation indoors or in the car.
2. Solar heat blocking method
In the solar heat blocking method of the present invention, the above-described solar heat blocking glass of the present invention is arranged so that the glass substrate surface faces the side irradiated with solar heat (absorbs solar heat), and the coating surface side The method is characterized in that the heat radiation from is cut off. That is, the solar radiation shielding glass has a visible light transmittance larger than that of the glass substrate (preferably 90% or more), and both the solar heat absorption rate and the radiation heat absorption rate in the wavelength region of room temperature thermal radiation are those of the glass substrate. The smaller surface (preferably the solar heat absorption rate is 0.01 to 11% and the radiant heat absorption rate is 0.01 to 20% in the wavelength range of room temperature thermal radiation). Arranged toward the inside of the space. Thereby, the heat radiation from the glass which became high temperature by absorbing solar radiation can be effectively blocked without darkening the inside.
In addition, by forming the above-mentioned coating on the side of the inside of a closed space such as indoors or cars of window glass of conventional structures, buildings, vehicles, etc., room temperature heat radiation from the glass that has become hot is blocked. It is possible to reduce the heat load caused by solar radiation in the room or in the vehicle.
BEST MODE FOR CARRYING OUT THE INVENTION
EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.
Example 1
Methyl methacrylate-ethyl acrylate-styrene copolymer is diluted with ethyl acetate to have different concentrations (each concentration; sample 1 = 0.1 wt%,
Sample 3 = added colorant (total solution concentration: 0.0001% by weight)
Sample 4 = added colorant and infrared absorber (total solution concentration: colorant; 0.0002% by weight, infrared absorber; 0.0005% by weight)
Here, as a colorant, “RED BW” (manufactured by Nippon Kayaku Co., Ltd.) 0.01% by weight and “Ultra Sky SE” (manufactured by Nippon Kayaku Co., Ltd.) 0.01% by weight were mixed with ethyl acetate. A mixed solution dissolved in was used. As the infrared absorber, a 1.0 wt% solution of “Epolite 2057” (solvent: mixed solvent of MEK / IPA / ethyl acetate / toluene) was used.
This solution was applied to one side of the same glass plate having a length of 50 cm and a width of 50 cm using a flow coating method to form a film. The theoretical value shown above was used for the value of the absorptance in the wavelength region of room temperature thermal radiation at this time. Here, the thickness of the glass plate is 5 mm. Also, the thicknesses of the coatings are as follows: Sample 1 = 0.04 μm,
The coating thickness was measured by the following method. Glass plate (0.5m long x 0.5m wide and 0.25m in area)2) When the liquid agent of each sample (for example, sample 1 solution with a concentration of 0.1% by weight) is coated by flow coating, the weight of the liquid agent that has flowed down is measured, and the reduced liquid component is the amount of the solid adhering to the glass. The weight was obtained by calculation, and “solid weight / glass area” was taken as the film thickness, and this value was used as the theoretical value of the film thickness. The same applies to other samples.
Next, seven cubic boxes (50 × 50 × 50 cm) having only one side opened with a 5 mm thick foamed polystyrene plate are coated with an uncoated glass plate and a coated glass plate in the opening of the box. Arranged and attached so that the surface was inside.
Place the coated glass plate and the uncoated glass plate with the opening facing up, place it in a room set at 20 ° C, and equilibrate the temperature in the box with a 50W to 60W infrared lamp above the glass. The temperature in the box at that time was measured. The results are shown in Table 1.
On the other hand, in the case of Samples 4 to 6 (Comparative Example), the radiant heat absorption rate in the wavelength range of room temperature thermal radiation of the coating is smaller than the glass plate, but the solar radiation heat absorption rate is larger than the glass plate. If the solar heat absorption rate of the film is larger than that of glass, the solar heat transmitted through the glass is absorbed more in the film than in the case of glass alone, and when the heat is dissipated to the outside air, the glass inhibits heat dissipation. Most of the absorbed heat goes into the box.
Usually, the heat absorbed by the glass includes heat that enters the enclosed space and heat that exits to the outside air, and the temperature inside the enclosed space (in the box) absorbs heat and solar heat that directly enters through the glass. It depends on the total heat entering from the glass that has become hot. In the case of Samples 4 to 6, the heat directly passing through the glass decreased, but the heat absorbed by the film was inhibited by the glass and hardly released to the outside air, and most of the heat absorbed by the film was absorbed. Since it entered the box, the total heat that enters the box from the glass and the coating that became hot by absorbing the direct sunlight through the glass and the solar heat increased, and the temperature inside the box was higher than that of the glass alone. Probably higher. That is, the samples 4 to 6 whose solar heat absorption rate of the coating was larger than the glass plate were higher than the case where the temperature in the box was only glass even if the radiation heat absorption rate in the wavelength region of the room temperature thermal radiation was smaller than glass. Is.
Example 2
Prepare a 5 mm thick Styrofoam box (50 x 50 x 50 cm) with an uncoated glass plate and a coated glass plate similar to those used in Example 1 so that the coated surface is on the inside. did.
When the coated glass plate and uncoated glass plate are installed in a wide area where the sunbeams are exposed, with the opening attached with the glass plate facing upward, The temperature was measured. As in Example 1, the theoretical values were used for the visible light transmittance, solar heat absorption rate, and room temperature thermal radiation absorption rate of the coating. The outside air temperature at this time was 34.6 ° C. The results are shown in Table 2.
On the other hand, in the case of Samples 4 to 6 (comparative examples) in which the radiant heat absorption rate in the wavelength range of the room temperature thermal radiation of the coating is smaller than that of the glass plate, but the solar heat absorption rate is larger than that of the glass plate, it directly passes through the glass However, the heat absorbed by the coating is hardly dissipated to the outside air, and most of the heat absorbed by the coating has entered the box, so that the heat that enters directly through the glass is reduced. It is thought that the total heat entering the box from the glass and the film that became high temperature by absorbing solar heat became larger, and the temperature in the box was higher than in the case of only glass.
Example 3
The volume is 55m in the 8th floor of a 9-story reinforced concrete building.3In addition, three identical rooms with 1.5m long and 2.8m wide rectangular windows with 5mm thick window glass on the east facing wall are prepared. In addition, the glass window in one room is poured with the paint having a solar heat absorption rate of 0.09% created in Example 1 and a radiation heat absorption rate (theoretical value) of 0.48% in the wavelength range of room temperature thermal radiation. Application was carried out using a coating method to form a film (thickness; 0.04 μm) (Sample 1).
And the window glass of the other room is a polyester film provided with an adhesive layer on the side to be adhered to the glass, and the solar radiation heat absorption rate is 0 on the side opposite to the adhesive layer as above. 0.09% coated with a solution having an absorptivity (theoretical value) in the wavelength range of room temperature thermal radiation of 0.48% (coating layer thickness: 0.07 μm, film thickness: 50 μm, adhesive layer (Thickness: 20 μm) was pasted on the indoor side (Sample 2). The other room was only window glass (Sample 3).
In a room (sample 1) in which a film is formed on a window glass, a room in which a polyester film is pasted (sample 2), and a room with only a window glass (sample 3), it is 1 m away from the window near the room when it is irradiated with sunlight. The temperature change over time at the point was measured. As in Example 1, theoretical values were used for the solar heat absorption rate and the radiant heat absorption rate of the coating. The results are shown in Table 3. The unit of numerical values in the table is ° C.
Example 4
Seven cubic boxes (50 × 50 × 50 cm) having only one surface opened with a polystyrene foam plate having the same thickness of 5 mm as that used in Example 1 were prepared.
The same paint as that used in Example 1 was applied by flow coating on the surface opposite to the adhesive layer of a 50 μm thick polyester film having an adhesive layer of 25 μm to form a film.
This film is pasted on a glass plate having a thickness of 5 mm via an adhesive layer (also prepared by pasting only a polyester film on which a film is not formed) so that the film-forming surface of the film is on the inside of the box Arranged. The glass was placed in a wide area where it was well exposed to sunlight, and the temperature when the inside of the box was in equilibrium when irradiated with sunlight was measured. The outside air temperature at this time was 34.9 ° C. As in Example 1, theoretical values were used for the solar heat absorption rate of the coating and the radiant heat absorption rate in the wavelength range of room temperature thermal radiation. The results are shown in Table 4.
The maximum temperature in the box when irradiated with sunlight is the solar heat absorption rate of the film and the absorption rate in the wavelength range of room temperature thermal radiation are both lower than that of the glass plate on which only the polyester film is applied. The maximum temperature is 0.1 to 2.0 ° C lower than the case of a glass plate with a polyester film only, and the radiant heat from the inner surface of the glass attached to the opening of a polystyrene foam box is reduced. It can be seen that a lot of heat was released.
On the other hand, the radiant heat absorption rate in the wavelength region of room temperature thermal radiation of the coating is smaller than the glass plate on which only the polyester film is pasted, but the solar radiation heat absorption rate is larger than the glass plate on which only the polyester film is pasted. In the case of), the heat directly passing through the glass decreased, but the heat absorbed by the film was inhibited by the glass and hardly radiated to the outside air, and most of the heat absorbed by the film was inside the box. The total amount of heat entering the box from the glass and the coating that has become high temperature by absorbing the direct sunlight through the glass and the solar heat is larger, and the temperature in the box is higher than that of glass alone. It is thought.
Example 5
Seven cubic boxes (50 × 50 × 50 cm) having only one surface opened with a polystyrene foam plate having the same thickness of 5 mm as that used in Example 1 were prepared.
And the coating material created in Example 1 was apply | coated by the same method as Example 1 to the heat ray absorption glass whose solar radiation heat absorption rate is 33.6%.
Next, as in Example 1, the heat ray absorbing glass was placed in the box so that the coating surface was inside the box, and the glass surface was placed facing up. And it installed in the wide place where sunlight hits well, and the temperature when the inside of the box when irradiated with sunlight was in equilibrium was measured. The outside air temperature at this time was 33.2 ° C. The results are shown in Table 5.
Industrial applicability
The solar heat-shielding glass of the present invention is a glass substrate on which a film having a high visible light band transmittance and a small solar heat absorption coefficient and a low room temperature thermal radiation wavelength band is formed. By installing the glass window made of this solar heat-shielding glass so that the coating surface faces the inside of the closed space such as a building or a vehicle (inside or inside the vehicle), the glass surface is heated by sunlight and the temperature rises. It is possible to prevent the heat radiation from the glass that is generated later from entering the interior, and to radiate a large amount of the radiation to the outside, thereby reducing the heat load in the room or the like.
Moreover, since the transparency of visible light inherent to glass is not impaired, an increase in temperature can be suppressed without darkening the room or the interior of the vehicle. Moreover, unlike conventional metals and ceramics, they can be easily manufactured and are inexpensive. Therefore, it can be effectively used as window glass or glass building materials for houses, cold storage warehouses, ceilings, walls, vehicles, and various containers.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing the structure of the solar heat insulation glass of the present invention. FIG. 2 is a graph showing temperature changes in the room over time in Example 3 of the present invention.
In FIG. 1, 1 is a glass substrate, 2 is a coating, A is the side irradiated with solar heat, and B is in a closed space. In FIG. 2, a indicates sample 1, b indicates
Claims (6)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002111572 | 2002-04-15 | ||
| JP2002111572 | 2002-04-15 | ||
| PCT/JP2003/004284 WO2003087004A1 (en) | 2002-04-15 | 2003-04-03 | Solar heat cutoff glass and solar heat cutoff method using same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPWO2003087004A1 true JPWO2003087004A1 (en) | 2005-09-29 |
| JP4553235B2 JP4553235B2 (en) | 2010-09-29 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2003583964A Expired - Fee Related JP4553235B2 (en) | 2002-04-15 | 2003-04-03 | Solar heat insulation glass and solar heat insulation method using the same |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP4553235B2 (en) |
| AU (1) | AU2003236362A1 (en) |
| WO (1) | WO2003087004A1 (en) |
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| JP6164906B2 (en) * | 2013-04-19 | 2017-07-19 | 株式会社翠光トップライン | Solar power module |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0881238A (en) * | 1994-09-12 | 1996-03-26 | Sekuto Kagaku:Kk | Thermal insulation glass |
| JPH08228609A (en) * | 1995-03-01 | 1996-09-10 | Sekuto Kagaku:Kk | Synthetic resin covering material for agriculture and plastic greenhouse for agriculture |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3444545B2 (en) * | 1993-11-18 | 2003-09-08 | 株式会社セクト化学 | Crop cultivation house |
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2003
- 2003-04-03 WO PCT/JP2003/004284 patent/WO2003087004A1/en active Application Filing
- 2003-04-03 AU AU2003236362A patent/AU2003236362A1/en not_active Abandoned
- 2003-04-03 JP JP2003583964A patent/JP4553235B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0881238A (en) * | 1994-09-12 | 1996-03-26 | Sekuto Kagaku:Kk | Thermal insulation glass |
| JPH08228609A (en) * | 1995-03-01 | 1996-09-10 | Sekuto Kagaku:Kk | Synthetic resin covering material for agriculture and plastic greenhouse for agriculture |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4553235B2 (en) | 2010-09-29 |
| WO2003087004A1 (en) | 2003-10-23 |
| AU2003236362A1 (en) | 2003-10-27 |
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