We report the development of a new building material, made from unfired vermiculite, calcium hydroxide, silica and pulp by autoclaving at 180°C. The product exhibits the vermiculite crystals dispersed uniformly in a definite direction among the matrix of calcium silicate.
The vermiculite board shows marked plastic deformation caused by interlayer sliding of vermiculite. This board is fixed by nails and screws and possible to cut and saw like artificial wood.
The board has superior humidity control, and the relative humidity in an experimental house is maintained to be 50%. Formaldehyde is chemically adsorbed onto the board, and there is no release of formaldehyde at elevated temperature. The board has higher fungus resistance compared to the other building products.
The board is a sustainable building material and can be recycled as silicate fertilizer and soil enhancer.

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The synthetic method of mica corresponding to three kinds of production situations is considered. Since the melting method has high concentration, yield becomes high.
The mineral kind which can do the biggest crystal of synthetic mica is fluoro-phlogopite (KMg₃A1Si₃O₁₀F₂). The feature of fl uoro-phlogopite is a pure crystal. Compared with it, the crystal of tetrasilsic mica does not become large like fluoro-phlogopite.
The greatest use of synthetic mica is cosmetics. It is mainly makeup cosmetics that synthetic mica is used. The high aspect ratio particle with transparent gloss is obtained only from fluoro-phlogopite. Transparent gloss hides a blotch or wrinkles, and it is shown like a bright natural skin.
The pure crystal of fluoro-phlogopite is not somber. It makes transparent gloss and clear interference color. Therefore, it is indispensable for basis material of pearl mica paints.
In recent years, there is much research of the silicon wafer polish using mica. The wafer ground by K tetrasilsic mica (KMg_2.5 Si₄O₁₀F₂) has few scratches, and a good polish side can be acquired.
The gas barrier film that coated Na tetrasilsic mica (NaMg_2.5 Si₄O₁₀F₂) and poly vinyl alcohol were devised for food packing. Na tetrasilsic mica synthesized by melting method have high aspect ratios. The film coated with Na tetrasilsic mica demonstrates high barrier nature.
Synthesis could give various characteristics, such as a high purity crystal, a large crystal, and a high aspect ratio, besides these, and various applied technologies have been developed

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Indoor climate controlling soil based materials were investigated for a sustainable technology. Hydrothermal reaction of soil and low temperature calcination of allophane were applied aiming at decreasing input energy and natural resources. Soil generally contains higher amount of A1₂0₃, yielding the formation of large hydrogarnet crystals as the prevention factor of the strength development of hydrothermal solidification. It was found that the formation of nano-sized hydrogarnet crystals by the controlling of reaction condition enables the strength development on the hydrothermal solidification of soil. Furthermore, the formation of mesoporous structure was suitable for the application to the humidity controlling materials or adsorption materials. For the low temperature calcination, allophane containing soil was used because of its high adsorption-desorption ability. The addition of waste glass additives enables the strength development and higher humidity controlling property simultaneously even at low firing temperature of 900°C. The room temperature and relative humidity in a house with the soil based material was measured, showing the effects of keeping the relative humidity, reducing dew condensation, and reduction of the energy utilized for living.

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Present situation and future survey of polymer/clay nanocomposites was introduced. The author concluded that relatively high heat distortion temperature of nylon6/clay nanocomposites should be highly estimated but that cost and performance of nylon6/clay nanocomposites were not so high compared with nylon6/glass fiber and polypropylene/glass fiber composites. High functional nanocomposites were proposed by utilizing highly activated interlayer of clay.

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Activated bleaching earth (ABE) is a commonly used adsorbent in decolorization process of fat and oil refining. The ABE is manufactured by treating montmorillonite clay with mineral acids such as sulfuric acid. During acid treatment, structure of the clay becomes porous by eluting basic metallic components such as aluminum, iron and magnesium. The activated clay has a large specific surface area and a large adsorption capacity enough to adsorb colored materials in oil refining process. Waste ABE, filtered cake of used ABE in the decolorization process, contains 35-40% processing oil by weight. Discharged amount of the waste ABE in Japan is estimated approximately 80, 000 tons a year. Although it is reutilized in part as subsidiary sources for Portland cement, compost etc., additional applications are required for stable waste material recycling.
Recently, special attention is given to fatty acid methyl esters (FAME) as potential substitutes of fossil fuels. The FAME, which is also known as biodiesel fuel (BDF), is converted from vegetable oil by transesterification and shows suitable properties as a diesel fuel. The BDF is considered a carbon neutral and eco-friendly fuel due to its regenerative potential and biodegradability. Its mutagenic effects, furthermore, are significantly lower than those of fossil fuels. Although the vegetable oils embeded in waste ABE are expected to be converted into BDF, it is difficult to apply a conventional conversion method. Because the vegetable oils react with methanol in the pore of ABE, it is hard to separate BDF from ABE. Potassium hydroxide, generally used as a transesterification catalyst, faces another problem because of neutralization by ABE.
Park reported the lipase-catalyzed production of FAME from waste ABE. Lipase worked actively in the presence of waste ABE and organic solvent such as n-hexane. Oils adsorbed inside the pore of waste ABE were extracted by the solvent, which made it possible to separate the liquid phase from the solid phase. The waste ABE worked not only as a medium for dispersion of reaction mixture but also as an adsorbent for by-produced glycerol. The organic solvent was evaporated from the FAME solution and was possibly reutilized. However, because the organic solvent is harmful to health and the environment, it is better to use a safe and harmless solvent or a solvent-free process.
To improve the lipase-catalyzed BDF production process from waste ABE, a diesel fuel was used as the organic solvent as a substitute of harmful n-hexane. The esterification rate in diesel fuel was higher than that in n-hexane. Furthermore, the separating process of the solvent was not required, because the final product was a mixture of FAME and diesel fuel. The results of fuel analysis demonstrated that the BDF consistingof FAME and diesel fuel was fit to those in the diesel fuel specifications based on Japanese Industrial Standards (JIS). Thus, the BDF production process was simplified by using diesel fuel as a solvent instead of using n-hexane.

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Pearl pigments are materials made by depositing titanium oxide thin layer on platy clay minerals such as mica. They are very useful in cosmetic industry. Usually, they are used for cosmetics formulae for giving a bright appearance on the lips or the skin. On the other hand, noble makeups using pearl pigment in quite different ways have been developed recently.
‘Neo-chiaroscuro’ makeup presents a new concept of makeup that can highlight and contour the face and allow the face to look slim. These unique functions are based on light reflection and absorption. A material that can give neo-chiaroscuro makeup is a pearl pigment of which surface is chemically reduced. It is called titanium lower oxide coated mica. By using this new cosmetic material, we have developed a makeup cosmetic that is designed to reflect a strong light coming from the front of the face to make a bright portion and absorb a light coming aslant to make the dark portion, resulting in the appearance of the contoured and slim-looking face.
Another pearl pigment is used to create a noble makeup for masking severe skin color problems such as Ota's nevus. Ota's nevus is very difficult to be masked by an ordinal hiding makeup technique such as using a conventional foundation with a high covering capability. The appearance of the face looks unnatural when the foundations or other makeups are applied heavily for covering the birthmark. However, the new foundation containing titanium oxide coated mica, which splits incident light into reflected light and transmitted light of complementary colors due to the interference phenomenon can vanish the birthmark even when it is applied lightly on the face. The phenomena is based on a new photo-complementary theory-the transmitted light from the titanium oxide coated mica that is complementary color to the birthmark compensates for the conspicuous birthmark.
These two pearl pigments for cosmetics are very significant and make the cosmetics more valuable. The flat and smooth structure of clay minerals enables us to develop these unique materials.

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Excellent properties of organic polymer/clay minelal hybrids, such as mechanical property, gas barrier effect and antifl amability, have attracted many attentions. These properties are attributed to weak interaction between organic polymers and the surface of silicate layers of montmorillonite, which were confirmed by X-ray diffraction, thermal analyses and IR-absorption experiments. Guest-guest and guest-silica surface interactions also play important rolls to understand the properties of metalcomplex molecules, such as chlorophyll, in nano-spaces in mesoporous silica; FSM. A weak hydrophobic interaction in nanometer scale should be studied to develop the nano-hybrid materials.

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M-type magadiites (M₂Si₁₄O₂₉·nH₂O, M: Li, Na, K, Rb, Cs) prepared by exchanging Na+ion of magadiite (Na₂Si₁₄O₂₉·nH₂O) with a series of alkaline metal ions M⁺, and silica gel treated with NaOH were studied by titrating their suspensions with HCl solution in an atmosphere of nitrogen. The reaction of neutralization was represented by the following equation.
=Si-O^- M⁺+H⁺→=Si-OH+M⁺
For the silica gel treated with NaOH, the resulting titration curve depicted upward curvature from the initial point to the equivalence point, because the dissociation constant of silanol groups is altered by the degree of neutralization.
For M-type magadiite that is a layered polysilicic acid, on the contrary, the titration curves with definitive equivalence points were obtained, which correspond that of bases such as molecules or ion species with the definite dissociation constants. The titration curves obtained from Na-type magadiite showed only an equivalence point, and that from the others showed two equivalence points. These data indicated that the position of the structural hydroxyl groups (=Si-OH) and the ionized groups (=Si-O^-) on the magadiites differ according to kinds of interlayer cations. Na-type magadiite was characterized with regard to remote=Si-O^-groups each other, and the other types were characterized by adjacent those groups.

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