- 著者
- Kana Kikegawa Kyuuichirou Takamatsu Masaru Kawakami Hidemitsu Furukawa Hiroyuki Mayama Yoshimune Nonomura
- 出版者
- 公益社団法人 日本油化学会
- 雑誌
- Journal of Oleo Science (ISSN:13458957)
- 巻号頁・発行日
- vol.66, no.4, pp.383-389, 2017 (Released:2017-04-03)
- 参考文献数
- 32
- 被引用文献数
- 2
Hierarchical structures, also known as fractal structures, exhibit advantageous material properties, such as water- and oil-repellency as well as other useful optical characteristics, owing to its self-similarity. Various methods have been developed for producing hierarchical geometrical structures. Recently, fractal structures have been manufactured using a 3D printing technique that involves computer-aided design data. In this study, we confirmed the accuracy of geometrical structures when Koch curve-like fractal structures with zero to three generations were printed using a 3D printer. The fractal dimension was analyzed using a box-counting method. This analysis indicated that the fractal dimension of the third generation hierarchical structure was approximately the same as that of the ideal Koch curve. These findings demonstrate that the design and production of fractal structures can be controlled using a 3D printer. Although the interior angle deviated from the ideal value, the side length could be precisely controlled.
- 著者
- Yuki Kawamura Hiroyuki Mayama Yoshimune Nonomura
- 出版者
- 公益社団法人 日本油化学会
- 雑誌
- Journal of Oleo Science (ISSN:13458957)
- 巻号頁・発行日
- vol.61, no.9, pp.477-482, 2012 (Released:2012-09-08)
- 参考文献数
- 32
- 被引用文献数
- 1 6
Liquid marbles are water droplets covered with solid particles. Here we show a method for the preparation of edible liquid marbles and capsules covered with fatty acid crystals and triacylglycerol crystals. We prepared liquid marbles using a simple method; namely, a water droplet was rolled on lipid crystals in petri dishes. The resulting marbles were converted to capsules covered with a lipid shell by heating. These marbles were stable not only on glass surfaces but also on water surfaces because they had rigid hydrophobic exteriors. The lifetime of the liquid marbles on water depended on the alkyl chain length of the lipid molecules and the pH of the water. These findings are useful for applying liquid marbles to food, cosmetic, and medical products.
- 著者
- Taro Oyama Hiroyuki Mayama Yoshimune Nonomura
- 出版者
- (社)日本化学会
- 雑誌
- Chemistry Letters (ISSN:03667022)
- 巻号頁・発行日
- vol.42, no.8, pp.871-872, 2013-08-05 (Released:2013-08-05)
- 参考文献数
- 11
- 被引用文献数
- 8
We have investigated the spreading process of oil-in-water emulsions containing oleic acid droplets on flat and rough fractal agar gel surfaces. Significant spreading inhibition owing to local condensation of oil droplets is observed on flat agar gel surfaces. On the other hand, such inhibition is not observed on the fractal gel surfaces for any of the emulsions. The rough structure of the gel surfaces is an important factor of spreading dynamics of emulsions on surfaces.
- 著者
- Ayano Kudo Marika Sato Haruna Sawaguchi Jun-ichi Hotta Hiroyuki Mayama Yoshimune Nonomura
- 出版者
- 公益社団法人 日本油化学会
- 雑誌
- Journal of Oleo Science (ISSN:13458957)
- 巻号頁・発行日
- vol.65, no.11, pp.909-912, 2016 (Released:2016-11-01)
- 参考文献数
- 12
- 被引用文献数
- 3
In the present study, mechanical phenomena on fractal agar gel were analyzed to understand the interfacial properties of hydrophilic biosurfaces. The evaluation of adhesion strength between the fractal agar gel surfaces showed that the fractal structure inhibits the adhesion between the agar gel surfaces. In addition, when the disintegration behavior of an agar gel block was observed between fractal agar gel substrates, the rough structure prevented the sliding of an agar gel block. These findings are useful for understanding the biological significance of rough structure on the biological surfaces.
- 著者
- Haruna Sawaguchi Hiroshi Nishida Takahiro Kawai Hiroyuki Mayama Yoshimune Nonomura
- 出版者
- (社)日本化学会
- 雑誌
- Chemistry Letters (ISSN:03667022)
- 巻号頁・発行日
- pp.150005, (Released:2015-02-14)
- 被引用文献数
- 1
We prepared an apatite/polymer composite material with a fractal surface by transferring the hierarchical rough surface of a plaster replica onto calcium phosphate paste and immersing the paste in buffer. The rough structure (fractal dimension = 2.3) accelerated the spreading and penetration of a water droplet placed on the surface. This material can be applied in dental implants and texture testers.
- 著者
- Yoshimune Nonomura Eri Seino Saya Abe Hiroyuki Mayama
- 出版者
- 公益社団法人 日本油化学会
- 雑誌
- Journal of Oleo Science (ISSN:13458957)
- 巻号頁・発行日
- vol.62, no.8, pp.587-590, 2013 (Released:2013-08-27)
- 参考文献数
- 12
- 被引用文献数
- 1 6
The elastomer materials with hieralchical structure and suitable wettability are useful as biological surface model. In the present study, urethane resin and silicone resin elastomers with hierarchical rough surfaces were prepared and referred to as “fractal elastomers”. We found a hierarchy of small projections that existed over larger ones on these surfaces. These elastomers were synthesized by transferring a fractal surface structure of alkylketene dimer. The rough structure enhanced the hydrophobicity and weakened friction resistance of the elastomer surfaces. These materials can be useful for artificial skin with biomimetic surface properties.
- 著者
- Taro Oyama Hiroyuki Mayama Yoshimune Nonomura
- 出版者
- (社)日本化学会
- 雑誌
- Chemistry Letters (ISSN:03667022)
- 巻号頁・発行日
- pp.130307, (Released:2013-05-30)
- 被引用文献数
- 8
We have investigated the spreading process of oil-in-water emulsions containing oleic acid droplets on flat and rough fractal agar gel surfaces. Significant spreading inhibition owing to local condensation of oil droplets is observed on flat agar gel surfaces. On the other hand, such inhibition is not observed on the fractal gel surfaces for any of the emulsions. The rough structure of the gel surfaces is an important factor of spreading dynamics of emulsions on surfaces.
- 著者
- Tomoya Tanaka Hiroyuki Mayama Yoshimune Nonomura
- 出版者
- (社)日本化学会
- 雑誌
- Chemistry Letters (ISSN:03667022)
- 巻号頁・発行日
- vol.41, no.9, pp.960-961, 2012-09-05 (Released:2012-09-01)
- 参考文献数
- 14
We successfully determined the three-dimensional structure of agar gel droplets on multipillared surfaces. The contact angle, length of penetration of the agar gel into the interspace between pillars, and curvature of the bottom surface of the droplets were changed with respect to changes in the volume and concentration of the aqueous agar solution and the distance between the surface-bound pillars.