Spreading Characteristics of Monolayer Lubricant Films on Surfaces With Lube Textures

2005 ◽  
Vol 127 (1) ◽  
pp. 164-170 ◽  
Author(s):  
Hedong Zhang ◽  
Yasunaga Mitsuya ◽  
Natsuko Fukuoka ◽  
Kenji Fukuzawa
Keyword(s):  
Diffusion Coefficients ◽  
Surface Characteristics ◽  
Disk Surface ◽  
Ultraviolet Rays ◽  
Monolayer Film ◽  
Magnetic Disk ◽  
Surface Energies ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Lubricant Films

In this paper, we investigate the effect of lube textures from the viewpoint of lubricant spreading. Lube textures, designating a patterned distribution of bonding strength between lubricant molecules and disk surface, were formed by irradiating ultraviolet rays through a stripe-patterned mask onto a magnetic disk surface which was partially coated with one-monolayer film of perfluoropolyether. Surface characteristics of the lube textures were evaluated by surface energies ascertained from contact angle measurements. Spreading of the lubricant film was measured by scanning microellipsometry on the striped lube textures in the directions parallel and perpendicular to the stripes. The thickness-dependent diffusion coefficients extracted from the spreading profiles show that lubricant spreading in the regime of film thickness less than 0.2 nm is faster along the stripes, indicating the possibility of controlling the behavior of lubricant films with lube textures.

Spreading Characteristics of Monolayer Lubricant Film on Surfaces With Lube Textures

2003 ◽  
Author(s):  
Hedong Zhang ◽  
Yasunaga Mitsuya ◽  
Natsuko Fukuoka ◽  
Kenji Fukuzawa
Keyword(s):  
Diffusion Coefficients ◽  
Surface Characteristics ◽  
Disk Surface ◽  
Nonuniform Distribution ◽  
Lubricant Film ◽  
Ultraviolet Rays ◽  
Monolayer Film ◽  
Surface Energies ◽  
Angle Measurements ◽  
Contact Angle Measurements

In this paper, from the viewpoint of lubricant spreading, we investigate the effect of lube textures which mean a nonuniform distribution of bonding strength between lubricant molecules and the disk surface. Lube textures were formed by irradiating ultraviolet rays through a stripe-patterned mask onto a magnetic disk surface which was partially coated with one-monolayer film of perfluoropolyether. Surface characteristics of the lube textures were evaluated by surface energies ascertained from contact angle measurements. Spreading of the lubricant film was measured by scanning microellipsometry on the striped lube textures in the directions parallel and perpendicular to the stripes. The thickness-dependent diffusion coefficients extracted from the spreading profiles show that lubricant spreading in the regime of film thickness less than 0.2 nm is faster along the stripes, indicating the possibility of controlling the behavior of a lubricant film with lube textures.

scholarly journals Surface properties and color stability of an acrylic resin combined with an antimicrobial polymer

2013 ◽  
Vol 42 (4) ◽  
pp. 237-242 ◽  
Author(s):  
Ana Carolina Pero ◽  
Jaqueline Ignárcio ◽  
Gabriela Giro ◽  
Danny Omar Mendoza-Marin ◽  
André Gustavo Paleari ◽  
...  
Keyword(s):  
Surface Properties ◽  
Color Stability ◽  
Acrylic Resin ◽  
Surface Characteristics ◽  
National Bureau ◽  
Color Changes ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Color Data ◽  
Student’S T

INTRODUCTION: The occurrence of stomatitis is common since the surface characteristics of the dentures may act as reservoirs for microorganisms and have the potential to support biofilm formation. PURPOSE: To assess the surface properties (wettability/roughness) and color stability of an acrylic resin combined with the antimicrobial polymer poly (2-tert-butylaminoethyl) methacrylate (PTBAEMA). MATERIAL AND METHOD: Thirty disc-shaped specimens of an acrylic resin (Lucitone 550) were divided into three groups: 0% (control); 5% and 10% PTBAEMA. Surface roughness values (Ra) were measured using a profilometer and wettability was determined through contact angle measurements using a goniometer and deionized water as a test liquid. Color data were measured with a spectrophotometer. Kruskal-Wallis and Dunn's test were used to compare roughness values. Wettability data were analyzed using ANOVA and Tukey's test. Color data were compared using the Student's t-test and ∆E values were classified according to the National Bureau of Standards (NBS). All statistical analyses were performed considering α=.05. RESULT: Significant differences (p<.05) were detected among the groups for roughness, wettability and color stability. According to the NBS, the color changes obtained in the 5% and 10% PTBAEMA groups were "appreciable" and "much appreciable", respectively. CONCLUSION: It could be concluded that PTBAEMA incorporation in an acrylic resin increased the roughness and wettability of surfaces and produced color changes with clinical relevance.

S1603-1-2 Effect of Ultraviolet Irradiation on Adhesive Force and Elongation of Monolayer Lubricant Films Coated on Magnetic Disk Surface

2009 ◽  
Vol 2009.5 (0) ◽  
pp. 203-204
Author(s):  
Yasuji OHSHIMA ◽  
Takashi SUMI ◽  
Hiroki Hoshida ◽  
Hedong ZHANG ◽  
Kenji FUKUZAWA ◽  
...  
Keyword(s):  
Ultraviolet Irradiation ◽  
Disk Surface ◽  
Adhesive Force ◽  
Magnetic Disk ◽  
Lubricant Films

Spreading of Novel Cyclotriphosphazine-Terminated PFPE Films on Carbon Surfaces

2004 ◽  
Vol 126 (4) ◽  
pp. 751-754 ◽  
Author(s):  
Norio Tagawa ◽  
Tadao Tateyama ◽  
Atsunobu Mori ◽  
Nagayoshi Kobayashi ◽  
Yoshinobu Fujii ◽  
...  
Keyword(s):  
Film Thickness ◽  
Diffusion Coefficients ◽  
Work Of Adhesion ◽  
Monolayer Film ◽  
Apparent Diffusion Coefficients ◽  
End Groups ◽  
Lubricant Films ◽  
Apparent Diffusion ◽  
Matano Interface ◽  
Carbon Surfaces

Spreading characteristics of novel cyclotriphosphazine-terminated Perfluoropolyether (PFPE) films on carbon surfaces were investigated experimentally by using a scanning micro-ellipsometer. The apparent diffusion coefficients of novel lubricants were also studied in order to evaluate the spreading speed and they were compared with the conventional Zdol. It was found that the mobility of cyclotriphosphazine-terminated PFPE films is lower than that of Zdol. This characteristics is dependent on the interactions between the end groups of the lubricants and carbon surfaces and it is found that the tendency of “work of adhesion” for the lubricants has a good correlation with the mobility tendency of the lubricants. In addition, the monolayer film thickness of novel lubricant films as well as conventional Zdol was identified, which was extracted using Matano interface method. As a result, the existing conformation of novel cyclotriphosphazine-terminated PFPE film on carbon surfaces could be estimated, based on the monolayer film thickness results.

Surface Energy and Wetting Behaviour of Plasma Etched Porous SiCOH Surfaces and Plasma Etch Residue Cleaning Solutions

2009 ◽  
Vol 145-146 ◽  
pp. 319-322 ◽  
Author(s):  
Nicole Ahner ◽  
Matthias Schaller ◽  
Christin Bartsch ◽  
Eugene Baryschpolec ◽  
Stefan E. Schulz
Keyword(s):  
Surface Energy ◽  
Dielectric Materials ◽  
Solid Surfaces ◽  
Plasma Etch ◽  
Surface Energies ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Additional Process ◽  
Low K ◽  
Etch Residue

The removal of plasma etch residues by wet cleaning is an alternative or additional process to plasma processes, which are known to degrade low-k and ultralow-k dielectric materials. Besides Cu/low-k compatibility wetting is an important issue for wet cleaning. Surface energy of solid and liquid is the key to understand the wetting behaviour. In this study we examined the energetic character of plasma etched/stripped solid surfaces, etch polymers and several cleaning solutions by contact angle measurements. The results show, that variations of the etching process can heavily change the energetic character of the solid. Calculating the surface energies of solid and liquid provides the possibility to make a prediction if a cleaning liquid will wet the surface which has to be cleaned.

scholarly journals Recovery of Spores from Thermophilic Dairy Bacilli and Effects of Their Surface Characteristics on Attachment to Different Surfaces

2007 ◽  
Vol 74 (3) ◽  
pp. 731-737 ◽  
Author(s):  
R. B. Seale ◽  
S. H. Flint ◽  
A. J. McQuillan ◽  
P. J. Bremer
Keyword(s):  
Milk Powder ◽  
Surface Characteristics ◽  
Phase System ◽  
Simple Relationship ◽  
Two Phase ◽  
Manufacturing Line ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Spore Adherence ◽  
And Control

ABSTRACT Spores from four Geobacillus spp. were isolated from a milk powder manufacturing line in New Zealand. Liquid sporulation media produced spore yields of ∼107 spores ml−1; spores were purified using a two-phase system created with polyethylene glycol 4000 and 3 M phosphate buffer. The zeta potentials of the spores from the four isolates ranged from −10 to −20 mV at neutral pH, with an isoelectric point between pH 3 and 4. Through contact angle measurements, spores were found to be hydrophilic and had relative hydrophobicity values of 10 to 40%, as measured by the microbial adhesion to hexadecane assay. The most hydrophilic spore isolate with the smallest negative charge attached in the highest numbers to Thermanox and stainless steel (1 × 104 spores cm−2), with fewer spores attaching to glass (3 × 103 spores cm−2). However, spores produced by the other three strains attached in similar numbers (P > 0.05) to all substrata (∼1 × 103 spores cm−2), indicating that there was no simple relationship between individual physicochemical interactions and spore adherence. Therefore, surface modifications which limit the attachment of one strain may not be effective for all stains, and control regimens need to be devised with reference to the characteristics of the particular strains of concern.

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