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A Langmuir–Blodgett film contains one or more monolayers of an organic material, deposited from the surface of a liquid onto a solid by immersing (or emersing) the solid substrate into (or from) the liquid. A monolayer is adsorbed homogeneously with each immersion or emersion step, thus films with very accurate thickness can be formed. This thickness is accurate because the thickness of each monolayer is known and can therefore be added to find the total thickness of a Langmuir–Blodgett film. The monolayers are assembled vertically and are usually composed of amphiphilic molecules (see Chemical polarity) with a hydrophilic head and a hydrophobic tail (example: fatty acids). Langmuir–Blodgett films are named after Irving Langmuir and Katharine B. Blodgett, who invented this technique while working in Research and Development for General Electric Co. An alternative technique of creating single monolayers on surfaces is that of self-assembled monolayers. Langmuir–Blodgett films should not be confused with Langmuir films, which tends to describe an organic monolayer submersed in an aqueous solution. ==Historical background== Advances to the discovery of Langmuir–Blodgett films began with Benjamin Franklin in 1773 when he dropped about a teaspoon of oil onto a pond. Franklin noticed that the waves were calmed almost instantly and that the calming of the waves spread for about half an acre. What Franklin did not realize was that the oil had formed a monolayer on top of the pond surface. Over a century later, Lord Rayleigh quantified what Benjamin Franklin had seen at a pond. Knowing that the oil, oleic acid, had spread evenly through water, then Lord Rayleigh calculated that the thickness of the film was 1.6nm by knowing the volume of oil dropped and the area of coverage. In addition, he used these calculations to prove the existence of the Avogadro number. With the help of her kitchen sink, Agnes Pockels showed that area of films can be controlled with barriers. She added that surface tension varies with contamination of water. She used different oils to deduce that surface pressure would not change until area was confined to about 0.2 nm2. This work was originally written as a letter to Lord Rayleigh who then helped Agnes Pockels become published in the journal, ''Nature'', in 1891. Agnes Pockels’ work set the stage for Irving Langmuir who continued to work and confirmed Pockels’ results. Using Pockels’ idea, he developed the Langmuir trough. His observations indicated that chain length did not impact the affected area since the organic molecules were arranged vertically. Langmuir’s breakthrough did not occur until he hired Katherine Blodgett as his assistant. Blodgett initially went to seek for a job at General Electric (GE) with Langmuir during her Christmas break of her senior year at Bryn Mawr College, where she received a BA in Physics. Langmuir advised to Blodgett that she should continue her education before working for him. She thereafter attended University of Chicago for her MA in Chemistry. Upon her completion of her Master's, Langmuir hired her as his assistant. However, breakthroughs in surface chemistry happened after she received her PhD degree in 1926 from Cambridge University. While working for GE, Langmuir and Blodgett discovered that when a solid surface is inserted into an aqueous solution containing organic moities, then the organic molecules will deposit a monolayer homogeneously over the surface. This is the Langmuir–Blodgett film deposition process. Through this work in surface chemistry and with the help of Blodgett, Langmuir was awarded the Nobel Prize in 1932. In addition, Blodgett used Langmuir–Blodgett film to create 99% transparent anti-reflective glass by coating glass with fluorinated organic compounds. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Langmuir–Blodgett film」の詳細全文を読む スポンサード リンク
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