Injection-molded plastic plate with hydrophobic surface by nanoperiodic structure applied in uniaxial direction

Sasaki, Shinya; Suzuki, Shojiro; Nakayama, Yuki

doi:10.1080/01694243.2014.973158

Cited by 7 publications

(6 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results showed that the water droplet did not reach the bottom of the re-entrant texture because it was sufficiently suspended to exceed the depth. It has also been reported that periodic structures applied in a uniaxial direction affect the apparent contact angles by less than 2% [34]. Our results were thus consistent with those of the previous report.…”

Section: Measurement Of Apparent Contact Angle and Sliding Characteri...supporting

confidence: 94%

Direct-micro-fabrication of Hydrophobic Surface with Re-entrant Texture on Metal Produced by Femtosecond-pulsed Laser

Kato

2022

Lasers Manuf. Mater. Process.

Self Cite

View full text Add to dashboard Cite

Re-entrant textures are promising geometries for hydrophobic surfaces, however a direct processing method of microscale re-entrant textures applicable for general industrial materials such as metals has yet to be established. The purpose of this study was to demonstrate a possibility of direct processing method of microscale re-entrant textures by using a femtosecond-pulsed laser. We designed a novel and simple optical unit including a pair of step mirrors and a newly designed aspherical condenser lens that enable processing of reverse-tapered uniaxial grooves. A maximum reverse-taper angle of 20° was achieved on stainless steel using a femtosecond-pulsed laser that could be controlled linearly with the step mirror angles. Four types of test-pieces with re-entrant texture composed of reverse-tapered grooves were fabricated with reverse-tapered angles of 5 – 20°. It was demonstrated that the apparent contact angle exhibited an increase in the processed angle of the re-entrant texture. The re-entrant structures on stainless steel achieved a hydrophobicity over 140° of apparent contact angle with good stability, and allowing water droplets to slide off.

show abstract

Section: Measurement Of Apparent Contact Angle and Sliding Characteri...supporting

confidence: 94%

Direct-micro-fabrication of Hydrophobic Surface with Re-entrant Texture on Metal Produced by Femtosecond-pulsed Laser

Kato

2022

Lasers Manuf. Mater. Process.

Self Cite

View full text Add to dashboard Cite

show abstract

“…11,[23][24][25][26][27][28][29][30][31][32] Various direct write and replication methods have been employed to micro/nanostructure bulk hydrophobic materials. Replication methods such as casting a polymer solution or melt on a template, 33,34 injection moulding, [35][36][37] hot embossing, 38,39 and sacrificial etching 7,40,41 have been utilized. Photolithography and femtosecond laser ablation have been used for structuring of the master, but both are time consuming and expensive.…”

Section: Introductionmentioning

confidence: 99%

Robust hybrid elastomer/metal-oxide superhydrophobic surfaces

2016

View full text Add to dashboard Cite

We introduce a new type of hybrid material: a nanostructured elastomer covered by a hard photoactive metal-oxide thin film resembling the exoskeleton of insects. It has extreme water repellency and fast self-recovery after damage. A new fabrication method for replicating high aspect ratio, hierarchical re-entrant aluminum structures into polydimethylsiloxane (PDMS) is presented. The method is based on a protective titania layer deposited by atomic layer deposition (ALD) on the aluminum template. The ALD titania transfers to the elastomeric scaffold via sacrificial release etching. The sacrificial release method allows for high aspect ratio, even 100 μm deep and successful release of overhanging structures, unlike conventional peeling. The ALD titania conformally covers the 3D multihierarchical structures of the template and protects the polymer during the release etch. Afterwards it prevents the high aspect ratio nanostructures from elasticity based collapse. The resulting nanostructured hybrid PDMS/titania replicas display robust superhydrophobicity without any further fluoro-coating or modification. Their mechanical and thermal robustness results from a thick nanostructured elastomeric layer which is conformally covered by ceramic titania instead of a monolayer hydrophobic coating. We have demonstrated the durability of these replicas against mechanical abrasion, knife scratches, rubbing, bending, peel tape test, high temperature annealing, UV exposure, water jet impingement and long term underwater storage. Though the material loses its superhydrophobicity in oxygen plasma exposure, a fast recovery from superhydrophilic to superhydrophobic can be achieved after 20 min UV irradiation. UV-assisted recovery is correlated with the high photoactivity of ALD titania film. This novel hybrid material will be applicable to the large area superhydrophobic surfaces in practical outdoor applications.

show abstract

“…In the literature, many authors correlated the hydrophobicity of a surface to its topography [ 25 , 40 ]. The presence of a hierarchical structure on a surface induces an increase of the hydrophobicity with respect to a smooth surface [ 41 ].…”

Section: Resultsmentioning

confidence: 99%

“…The latter surely presents the advantage of cheaper and faster production [ 20 , 21 , 22 , 23 , 24 ]. Yamaguchi et al [ 25 ] proposed to replicate a master having nano-periodic structures, obtained by a femtosecond laser, layered on the cavity surface. They studied the effect of nano-structures replica on the wettability of acrylonitrile-ethylene-styrene moldings and found that the apparent contact angle increases with respect to the surface obtained on a smoother cavity.…”

Section: Introductionmentioning

confidence: 99%

Hydrophobicity Tuning by the Fast Evolution of Mold Temperature during Injection Molding

et al. 2018

View full text Add to dashboard Cite

The surface topography of a molded part strongly affects its functional properties, such as hydrophobicity, cleaning capabilities, adhesion, biological defense and frictional resistance. In this paper, the possibility to tune and increase the hydrophobicity of a molded polymeric part was explored. An isotactic polypropylene was injection molded with fast cavity surface temperature evolutions, obtained adopting a specifically designed heating system layered below the cavity surface. The surface topology was characterized by atomic force microscopy (AFM) and, concerning of hydrophobicity, by measuring the water static contact angle. Results show that the hydrophobicity increases with both the temperature level and the time the cavity surface temperature was kept high. In particular, the contact angle of the molded sample was found to increase from 90°, with conventional molding conditions, up to 113° with 160 °C of cavity surface temperature kept for 18 s. This increase was found to be due to the presence of sub-micro and nano-structures characterized by high values of spatial frequencies which could be more accurately replicated by adopting high heating temperatures and times. The surface topography and the hydrophobicity resulted therefore tunable by selecting appropriate injection molding conditions.

show abstract

Injection-molded plastic plate with hydrophobic surface by nanoperiodic structure applied in uniaxial direction

Cited by 7 publications

References 29 publications

Direct-micro-fabrication of Hydrophobic Surface with Re-entrant Texture on Metal Produced by Femtosecond-pulsed Laser

Direct-micro-fabrication of Hydrophobic Surface with Re-entrant Texture on Metal Produced by Femtosecond-pulsed Laser

Robust hybrid elastomer/metal-oxide superhydrophobic surfaces

Hydrophobicity Tuning by the Fast Evolution of Mold Temperature during Injection Molding

Contact Info

Product

Resources

About