No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Fingerprint resistant coatings for stainless steel substrates
Abstract
In this paper, development of coatings with anti-finger print feature for stainless steel substrates is presented. Coatings with tailored surface roughness are demonstrated which provide these properties. Polyurethane coatings are produced by incorporation of matting agents with different particle size and surface chemistry. Depending on the amount of incorporated matting agents and their particle size, we were able to obtain anti-finger print coatings with the designed surface patterns. Chemical resistance tests of the coatings prove that they are chemically durable to be utilized in daily activities.
... Recently, there is a considerable interest in keeping the surface clean and free from contamination such as fingerprint and dirt. Since the number of electronic devices with touch screens are increasing, the demands for anti-fingerprint technology are believed to increase significantly over the coming years [5,8]. ...
... Previously, the studies have demonstrated the possibility of constructing AF coating on various materials, which provided the properties of anti-stain and easy-maintain on the surface [6][7][8][9][10][11][12][13]. Anti-fingerprint coating contains perfluorinated compound and it possess low surface energy. ...
... Anti-fingerprint coating contains perfluorinated compound and it possess low surface energy. Therefore, anti-fingerprint coating prevents the possible contaminants affection and prevents their transfers from the users' fingers to the device [8,[14][15][16][17][18][19]. ...
We demonstrate the procedure of fabricating an anti-fingerprint coating on plated-Cr/brass substrates by the combination of two processes: (1) Sputtering and (2) Atmospheric pressure plasma jet (APPJ). APPJ surface treatment on sputtered-SiOx glue layer on plated-Cr/brass substrate is conducted to improve its surface property to be hydrophilic for chemical bonding with an anti-fingerprint agent (AF-C01). The results show that the surface energy of original substrate are evolving from 44.2 mN/m to 60.8 mN/m and 76.9 mN/m for the sputtered-SiOx film and APPJ-treated SiOx film, respectively. Subsequently, the spin-coating process using a commercialnt (AF-C01 agent for the prepared sample is implemented. The hydrophobicity of anti-fingerprint characteristics for all of the samples with a quite low surface energy around 10.5 mN/m are obtained. For practical evaluation of abrasion behavior, a good abrasion resistance of AF/APPJ-treated SiOx/plated-Cr/brass sample under 1000 g-steel wood loading is evidently obtained from the slow variation of water contact angle value. The results demonstrate that the feasibility of integrating APPJ process on the sputtered-SiOx film for improving the surface properties of chrome-plated brass substrate is practically achieved.
... Therefore, there is considerable interest in keeping the surfaces of devices free from fingerprints and dirt. Antifouling films and coatings are being developed for this purpose (Kesmez et al., 2017). In addition, a method of changing the surface shape by adding a microstructure to the material surface has been developed (Jheng and Lee, 2016;Saito et al., 2008;Tokuhisa et al., 2017). ...
The use of various types of information devices equipped with touch panels has been increasing. When these devices are used directly with fingers, the devices become dirty owing to sweat and oil from users. Therefore, there is considerable interest in keeping the surfaces of devices free from fingerprints and dirt. Antifouling films and coatings are being developed for this purpose. In addition, a method of changing the surface shape by adding a microstructure to a material surface has been developed. The purpose of this study is to add the antifouling function to glass surfaces using a mechanical removal process. We attempted to change the surface shape by processing a material surface directly. The processing method was microslurry-jet (MSJ) processing, which is a mechanical removal method. In addition, a masking process was used to create microsurface structures. As an example, we evaluated the anti-fingerprint glass created by these processing methods. Microsurfaces were successfully created on the glass surface through the combination of the masking process and MSJ processing. Moreover, the visibility of the created glass, surface characteristics, friction characteristics, and the adhesion of stains were evaluated. With respect to visibility, surface characteristics, and adhesion, it was possible to observe the changes in surface characteristics due to the microsurfaces. With regard to friction characteristics, differences in surface patterns were found for individual subject data.
... Using artificial sebum and a standard deposition protocol (e.g., quantity of matter, pressure, surface area, deposition time), Stoehr et al. emphasized the resistance to cleaning of secretion residue, which undergoes a shear banding phenomenon [557]. In a study aiming at proposing an antifingerprint coating for stainless steel, Kesmez et al. investigated the impact of surface roughness on the ability for a fingertip (contaminated with a mix of artificial sebum and sweat) to transfer material [558]. The combination of a mesoporous layer embedding enzymatic molecules (e.g., lipases) was proposed as a new anti-fingerprint coating [559]. ...
This review paper covers the forensic-relevant literature in fingerprint and bodily impression sciences from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium.
For citation, please refer to the published version of the report (open access):
https://doi.org/10.1016/j.fsisyn.2020.01.013
We have developed novel coating materials capable of absorbing fingerprint oils over time. When touch screens are operated with fingers, these oils adhere to the surface, rendering them visibly dirty. When finger oils adhere to anti-reflective coatings and structures, such as moth-eye films, their anti-reflective efficacy is substantially compromised. Specifically, in moth-eye films, the oils penetrate the grooves of the bell-shaped array and are difficult to remove. In this paper, we discuss our investigation into a technique for developing anti-fingerprint properties using these novel coating materials.
The advent of nanotechnology has inaugurated new era of ingenuity, particularly evident in the domain of nanocoating with diverse applications across industries. The coatings herald a transformative shift in surface protection. In the automotive sector, they play crucial role in enhancing scratch resistance and bolstering durability, thereby extending lifespan of vehicles. The packaging industry reaps the benefits of nanotechnology through the integration of advanced barrier properties, augmenting food preservation and packaging integrity. In the realm of healthcare, nanocoating applied to medical devices act as deterrents to microbial adhesion, fostering a hygienic environment. On the other hand, the electronics industry embraces nanocoating to establish water-resistant and robust surfaces, ensuring the prolonged endurance of electronic components. Thus, nanocoating has applications ranging from self-cleaning surfaces to improved insulation in sustainable building practices.
The focus of this chapter is to describe the forensic uses of fingermarks and fingerprints over the years and their awaited evolution. To do this, past conceptions are combined with the current knowledge status to highlight the overall potential of fingermarks and friction ridge skin patterns. For each application, the main academic and operational challenges are described.
Existing methods for the microfabrication of convex structures on a glass surface require a complex and expensive masking process. In this study, a simple microfabrication method that combines the masking process using polyimide tapes and a micro-slurry jet (MSJ) process was developed. The masking process was performed using a CO₂ laser machine, and the surface of the processed glass was observed using a three-dimensional laser microscope. Although the geometric shape of the mask was not a perfect circle, convex structures with a diameter of approximately 1.0 mm and heights of more than 1.5 μm were formed on soda-lime glass surfaces. The deepest structures were observed to create convex structures with a height of 19 µm. The effects of the travel speed of the nozzle and number of repetitions of the MSJ process on the height of the convex structures on the glass surface were also investigated. It was found that the masking process combining polyimide tapes and the MSJ process could form high-convexity structures on the glass surface. The proposed method is expected to enable the fabrication of devices with various functional properties for materials that cannot be processed using existing methods.
This review paper covers the forensic-relevant literature in fingerprint and bodily impression sciences from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review paper is available at this address: https://doi.org/10.1016/j.fsisyn.2020.01.013
Optical functional coatings of both easy-to-clean coatings and antiglare coatings have been spray deposited on pre-treated glass surface followed by a low temperature curing at 150°C. Easy-toclean EC coatings have excellent steel wool wear durability and low COF of = 0.03. Anti-glare AG201 coatings have tunable gloss value between 50 to 100 GU, pencil hardness =8H, and no sparkling issue.
The acquisition of future research demands in the field of innovative coatings materials was the aim of the so-called “Research agenda surface technology”, a project funded by the German Ministry of Education and Research and coordinated by the German Research Society of Surface Treatment (DFO, Neuss). Several German research institutions and numerous representatives of companies acting in the field of surface technology were involved in identifying the research demands in this area for the next 10–15 years.The functions of coated materials that were identified as the most innovative ones and having the biggest research driving force will be described for certain industrial branches. The most promising coating materials aimed to fulfill the desired functions in the future are discussed, visions are mentioned and conclusions about general trends in the field of coating materials are drawn.
In the present work, orienting to practicality and functionality beyond original fundamental simulation, we succeeded in fabricating superamphiphobic surfaces, which are super-repellent both to water and oil, upon common engineering metals (zinc, aluminum, iron, and nickel) and their alloys (Zn−Fe alloy and brass) by taking advantage of an electrochemical reaction in perfluorocarboxylic acid solutions. Via control over the chain length, concentration of perfluorocarboxylic acid, and the process time, textured rough structures on different substrates were achieved. The prepared surfaces show superamphiphobicity due to the synergistic effect of their special surface compositions and microscopic structures.
Applied Surface Science j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / a p s u s c a b s t r a c t An artificial fingerprint liquid is formulated from artificial sweat, hydroxyl-terminated polydimethyl-siloxane and a solvent for direct determination of anti-fingerprint property of a coated surface. A range of smooth and rough surfaces with different anti-fingerprint (AF) properties were fabricated by sol–gel technology, on which the AF liquid contact angles, artificial fingerprint and real human fingerprints (HF) were verified and correlated. It is proved that a surface with AF contact angle above 87 • is fingerprint free. This provides an objective and quantitative test method to determine anti-fingerprint property of coated surfaces. It is also concluded that AF property can be achieved on smooth and optically clear surfaces. Deep porous structures are more favorable than bumpy structure for oleophobic and AF properties.
As compared to superhydrophobic surfaces, the challenge to obtain superoleophobic properties, surfaces against low-surface-tension probe liquids such as hexadecane, is very important because of their high tendency to wet. From the molecular design of the monomer, it is possible to obtain in one step superoleophobic surfaces by electrodeposition. Hence, we report the synthesis and the characterization of an original series of fluorinated 3,4-ethylenedioxypyrrole (EDOP) derivatives. The electrodeposited polymer films are characterized by contact angle measurements (static and dynamic with various probe liquids), optical profilometry, and scanning electron microscopy. In the view toward reaching superoleophobic properties, a common approach is to increase the number of fluoromethylene units of the surface post-treatment agent. Here, surprisingly, it is possible, in one step, to reach more efficient antioil surface properties by decreasing the length of the fluorinated tail (F-octyl to F-hexyl). This fact can be explained by a double scale of structuration (micro and nano) induced using only F-hexyl tails.
We demonstrate that superhydrophobic and superoleophobic nanocellulose aerogels, consisting of fibrillar networks and aggregates with structures at different length scales, support considerable load on a water surface and also on oils as inspired by floatation of insects on water due to their superhydrophobic legs. The aerogel is capable of supporting a weight nearly 3 orders of magnitude larger than the weight of the aerogel itself. The load support is achieved by surface tension acting at different length scales: at the macroscopic scale along the perimeter of the carrier, and at the microscopic scale along the cellulose nanofibers by preventing soaking of the aerogel thus ensuring buoyancy. Furthermore, we demonstrate high-adhesive pinning of water and oil droplets, gas permeability, light reflection at the plastron in water and oil, and viscous drag reduction of the fluorinated aerogel in contact with oil. We foresee applications including buoyant, gas permeable, dirt-repellent coatings for miniature sensors and other devices floating on generic liquid surfaces.
New fluoropolyurethane hybrids containing fluorinated polyhedral oligomeric silsesquioxane were synthesized for thin film applications using fluoro(13) disilanol isobutyl-POSS (FluoroPOSS) and a short chain fluorodiol and diisocyanate. The kinetics of the urethane reaction was monitored using Fourier transform infrared spectroscopy (FTIR) and the formation of urethane was confirmed using (29)Si Nuclear magnetic resonance spectroscopy (NMR). The effect of addition of FluoroPOSS either in the I step or II step of the two step polymerization reaction is evaluated using various spectroscopic, thermal, microscopic, and diffraction techniques. In general, the major shortcoming of the lack of flexibility of fluoropolyurethane from short chain diol and diisocyanate has been overcome by the use of tethered FluoroPOSS. X-ray photoelectron spectroscopy (XPS), atomic force microscpopy (AFM), and contact angle measurements on the hybrid thin films on silicon wafer demonstrate the migration of FluoroPOSS segment to the air-thin film interface when FluoroPOSS is used in I stage reaction, and it resides at the interface when used as a chain extender. However, in both cases, the formed thin film exhibits ultrahydrophobicity with water contact angle of approximately 107 degrees and low contact angle hysteresis and solvent resistance, which are preferable for protective thin film applications.
Biomimetics, mimicking nature for engineering solutions, provides a model for the development of superhydrophobic/superoleophobic and self-cleaning surfaces. A number of biomimetic superhydrophobic surfaces have been developed by using a hydrophobic coating, surface roughness, and the ability to form air pockets between solid and water. Oleophobic surfaces that have the potential for self-cleaning and antifouling from biological and organic contaminants in both air and water need to be studied. The surface tension of oil and organic liquids is lower than that of water, so to create a superoleophobic surface, the surface energy of the solid surface in air should be lower than that of oil. The wetting behavior of water and oil droplets for hydrophobic/philic and oleophobic/philic surfaces in three-phase interfaces was studied. In order to make the surface oleophobic at a solid-air-oil interface, a material with a surface energy lower than that of oil was used. In underwater applications, the oleophobicity/philicity of an oil droplet in water was studied on the surfaces with different surface energies of various interfaces and contact angles of water and oil droplets in air. A model for predicting the contact angles of water and oil droplets was proposed. To validate the model, the wetting behavior of flat and micropatterned surfaces with varying pitch values were studied. Furthermore, the wetting behavior of the nano- and hierarchical structures found in Lotus plant surfaces and the shark skin replica as an example of aquatic animal were also studied. On the basis of the experimental data and the model, the trends were explained.
We demonstrate that porous Si films fabricated by a convenient gold-assisted electroless etching process, which possess a hierarchical porous structure consisting of micrometer-sized asperities superimposed onto a network of nanometer-sized pores, are able to induce a superhydrophobic phenomenon on an intrinsically hydrophilic hydrogen-terminated Si surface and a superoleophobic phenomenon on an intrinsically oleophilic self-assembled monolayer-coated Si surface. Through comparison with porous Si films consisting of vertically aligned straight pores, which are hydrophilic and oleophilic, we show that an overhang structure resulting from the hierarchical porous structure is essential to preventing water and oil from penetrating the texture of the films and inducing the observed macroscopic superhydrophobic and superoleophobic phenomena.
EP 2042533 Method for restoring or executing an anti-fingerprint coating onto sheets of stainless steel, in, European Patent Office
- F Colaiacovo
- S Tortora
- L Tortoreto
- S Mauro
- G Salamone
F. Colaiacovo, S., Tortora, L., Tortoreto, S., Mauro, G. Salamone, EP 2042533
Method for restoring or executing an anti-fingerprint coating onto sheets of stainless
steel, in, European Patent Office, 2010.
EP 1555249 Hydrophobic and/or oleophobic coating on microstructured glass surfaces providing an anti-fingerprint effect, in, European Patent Office
- M Hoffmann
- G D Jonschker
- M D Overs
M. Hoffmann, G.D., Jonschker, M.D. Overs, EP 1555249 Hydrophobic and/or
oleophobic coating on microstructured glass surfaces providing an anti-fingerprint
effect, in, European Patent Office, 2005.
US 20100216929 Anti-fingerprint coating material for stainless steel outer case of home appliance
- D J Jung
- H W Jun
D.J. Jung, H.W. Jun, US 20100216929 Anti-fingerprint coating material for stainless steel outer case of home appliance, in, USPTO, 2010.