RENIAS Co.

Mihara, Japan

RENIAS Co.

Mihara, Japan
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Nojiri H.,Japan National Defense Academy | Nojiri H.,Renias Co. | Pambudi W.S.,Japan National Defense Academy | Okoshi M.,Japan National Defense Academy
Japanese Journal of Applied Physics | Year: 2017

Periodic microswelling structures were photochemically induced on a silicone rubber surface using a 193 nm ArF excimer laser. Microspheres made of silica glass (SiO2) of 2.5μm diameter were aligned on the silicone rubber surface during laser irradiation; the laser beam was focused on the silicone surface underneath each microsphere. The height and diameter of the formed microswelling structures were found to be controllable by changing the Ar gas flow rate, single-pulse laser fluence, and laser irradiation time. The chemical bonding of the laser-irradiated sample did not change and thus remained to be a silicone, as analyzed by X-ray photoelectron spectroscopy. As a result, microswelling structures of approximately 1.3μm height and 1.3μm diameter were successfully obtained. The contact angles of water on the microstructured silicone were measured to be 150° and larger, clearly indicating superhydrophobicity. The mechanism by which the microswellings form their shape was discussed on the basis of the changes in the focal point and spot size during laser irradiation through the SiO2 microsphere. © 2017 The Japan Society of Applied Physics.


Nojiri H.,Japan National Defense Academy | Nojiri H.,Renias Co. | Okoshi M.,Japan National Defense Academy
Japanese Journal of Applied Physics | Year: 2017

A crack-free SiO2 film was successfully fabricated on silicone-coated polycarbonate (PC) even under heat resistance tests at 100 and 120 °C for 3 h by an additional rubbing treatment with steel wool for use as an automobile window material. The SiO2 film was formed by 157nm F2 laserinduced photochemical surface modification of silicone on PC. The modified SiO2 layer was also zoned with a mesh mask during the laser irradiation. The zoned SiO2 layer was effective for suppressing cracks during laser irradiation. However, even the zoned layer caused cracks under heat resistance tests. A mechanism of the cracking was analyzed on the basis of observations of sample surfaces by confocal laser microscopy. The rubbed samples showed high heat resistance. By atomic force microscopy, the surface of the modified SiO2 layer was clearly observed to be textured, which reduced the large difference in the thermal expansion coefficient between SiO2 and silicone on PC, thus maintaining optical transparency. © 2017 The Japan Society of Applied Physics.


Okoshi M.,Japan National Defense Academy | Iwai K.,Japan National Defense Academy | Nojiri H.,RENIAS Co. | Inoue N.,Japan National Defense Academy
Japanese Journal of Applied Physics | Year: 2012

A vacuum-UV F2 laser of 157nm wavelength induced strong oxidation of 10-nm-thick Al thin films, forming transparent Al2O 3 on silica glass. The laser-induced modification occurred at the surface of Al thin films; consequently, the thickness of the formed Al 2O3 thin films increased linearly with increasing number of F2 laser photons. The formation of equivalent-phase Al 2O3 thin films was confirmed by X-ray photoelectron spectroscopy. The oxidation reaction in the laser-induced modification of 10-nm-thick Al thin films was slower than that for 20- and 60-nm-thick Al thin films. Morphological changes leading to the crystallization of the Al 2O3 thin films were also observed when the thickness of Al thin films increased from 10 to 20 and 60 nm. © 2012 The Japan Society of Applied Physics.


Nojima Y.,Japan National Defense Academy | Nojima Y.,RENIAS Co. | Okoshi M.,Japan National Defense Academy | Nojiri H.,RENIAS Co. | Inoue N.,Japan National Defense Academy
Japanese Journal of Applied Physics | Year: 2010

A transparent, hard silica glass (SiO2) layer was formed on a conventional protective coat made of silicone ([SiO(CH3)2]n ) on a polycarbonate plate by the 157nm F2 laser-induced photochemical modification of silicone into SiO2. An optimum laser irradiation time of the F 2 laser was found to form a crack-free SiO2 layer. The high optical transparency of the samples in the visible light region remained unchanged after the F2 laser irradiation. In the Taber abrasion test, the SiO2 layer markedly reduced the number of scratches, resulting in a low haze value. The haze values ofthe samples also depend on the thickness of the silicone protective coat underneath the SiO2 protective layer. As a result, the difference of haze value (-Hz) was successfully reduced to 3.6%, compared with these of the nonirradiated sample and a bare polycarbonate plate of approximately 11.3 and 41.3%, respectively, which is comparable to the case of a bare silica glass of approximately 1.6%. In addition, the thickness of the SiO2 protective layer was estimated to be approximately 0.44 mm for the 30-s laser irradiation by immersing the samples in 1wt% hydrogen fluoride aqueous solution and measuring the depth using a surface profilometer. © 2010 The Japan Society of Applied Physics.


Iwai K.,Japan National Defense Academy | Iwai K.,RENIAS Co. | Okoshi M.,Japan National Defense Academy | Nojiri H.,RENIAS Co. | Inoue N.,Japan National Defense Academy
Japanese Journal of Applied Physics | Year: 2011

Photochemical surface and interface modifications of Al thin films on silica glass were successfully carried out using a 157nm F 2 laser for micropatterning. The surface modification phenomenon was discussed in relation to by changing the laser wavelength using a 193nm ArF laser or a 266nm neodymium-doped yttrium aluminum garnet (Nd:YAG) laser. The ArF laser could induce the surface modification of Al thin films to form a protective Al 2O 3 layer resistant to KOH aqueous solution, similarly to the F2 laser. However, the mechanical hardness of the ArF-laser-irradiated sample was clearly lower than that of the F 2-laser-irradiated sample. The origin of the surface modification was examined by irradiating the F 2 laser in vacuum. The interface modification phenomenon was analyzed by X-ray photoelectron spectroscopy in the three cases. The adhesion strengths of the samples were also compared. The 266nm Nd:YAG laser was not effective for the present photochemical modifications. © 2011 The Japan Society of Applied Physics.


Iwai K.,Japan National Defense Academy | Iwai K.,RENIAS Co. | Okoshi M.,Japan National Defense Academy | Nojiri H.,RENIAS Co. | Inoue N.,Japan National Defense Academy
Japanese Journal of Applied Physics | Year: 2011

A 157nm F2 laser induced strong oxidation of an Al thin film surface, allowing it to show chemical resistance to KOH aqueous solution used for selective metallization on silica glass or native oxide Si substrate. The strong oxidation reactions on the surface and in the depth direction were confirmed by X-ray photoelectron spectroscopy. A high adhesion strength of 663 kgf/cm2 between Al and silica glass was also obtained for the F 2-laser-irradiated sample, compared with that of the nonirradiated sample, 16 kgf/cm2. The suitable thickness of Al thin films for the F2-laserirradiated surface and interface modifications was examined to be approximately 20 nm. The mechanism of the F2-laser-induced interface modification was discussed regarding the dependence of substrate material and the analyses of the chemical bonding state of silica glass underneath Al thin films. © 2011 The Japan Society of Applied Physics.


Sonobe S.,Japan National Defense Academy | Nojima Y.,Japan National Defense Academy | Nojima Y.,RENIAS Co. | Okoshi M.,Japan National Defense Academy | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

Silicone-coated polycarbonate (PC) through an acrylic primer was photochemically modified into silica (SiO 2) by 157 nm F 2 laser. The photomodified surface showed high scratch resistance comparable to the case in a bulk silica. Corresponding to the conversion of silicone into silica on PC, the photomodified surface was found to be shrunk, measured by a surface profilometer. For instance, the coated silicone on PC reduced the thickness of approximately 15 % when the F 2 laser modified silicone into silica 0.59 μm in thickness. An excess irradiation of F 2 laser for the photochemical modification induced the degradation of acrylic primer underneath silicone.


Iwai K.,Japan National Defense Academy | Iwai K.,Renias Co. | Okoshi M.,Japan National Defense Academy | Nojiri H.,Renias Co. | Inoue N.,Japan National Defense Academy
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

A 157 nm F2 laser was used for the surface and interface modifications of Al thin films on silica glass substrate for fabricating a pattern of Al thin films. The F2-laser irradiated surface swelled remarkably by inducing the strong oxidation reaction of Al thin films to form Al2O3 protective layer. High adhesion strength of 663 kgf/cm2 between Al and silica glass was also obtained for the F 2-laser-irradiated sample, compared with the cases in the ArF-laser irradiated, fourth harmonic of Nd:YAG-laser irradiated and nonirradiated samples of 326, 19 and 16 kgf/cm2, respectively. Thus, the F 2-laser irradiated sample showed high abrasion resistance for embossing a fine pattern of Al thin films on silica glass. Mechanism of the F2-laser-induced surface and interface modifications was discussed, comparing with the cases in the ArF laser and fourth harmonic of Nd:YAG laser.


Trademark
Renias Co. | Date: 2014-02-19

Prefabricated building assembly kits of metal; road signs of metal (not luminous nor mechanical); beacons of metal (non-luminous); signboards of metal; casement windows of metal; window frames of metal; windows of metal. Workmens protective face-shields; protection devices for personal use against accidents; solar batteries; electronic glass for liquid crystal displays; optical lenses; objective lenses (optics). Windows for vehicles; sun visors for ships; sun visors for aircrafts; sun visors for railways; sun visors for automobiles; sunroofs for automobiles; sun-blinds adapted for automobiles. Plastic sheeting for agricultural purposes; semi-processed plastic substances. Plastic building materials; buildings (not of metal); building glass; window glass, except glass for vehicle windows; windows (not of metal); signs (not of metal, non-luminous and non-mechanical); beacons (not of metal and non-luminous); outdoor blinds (not of metal and not of textile).

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