Decorative Coatings Research Articles

TRADITIONAL AND NON-TRADITIONAL DECORATIVE COATINGS OF JEWELLERY AND COSTUME JEWELLERY

A wide range of protective and decorative coatings and materials used in the manufacture of jewellery and costume jewellery is considered. It is shown that the use of certain coatings and technologies of their application or formation is determined by the materials used. The classification and scheme of using decorative coatings on the surface of the main groups of materials used in the manufacture of jewellery and costume jewellery is proposed. The coatings are divided into two main groups – traditional and non-traditional. Traditional coatings include coatings, the technology of formation and decorative properties of which have recently undergone significant modernisation. The non-traditional ones include relatively new decorative coatings, which have become widely used in the manufacture of jewellery and costume jewellery in recent decades. It is noted that the development of material science and technological base of jewellery industry leads to the emergence of new interesting coatings, which allows to significantly diversify the possi-bilities of jewellery creators.

Gluconate solutions for nickel electrodeposition and nickel electroless plating

Nickel electroplating has found a wide range of industrial applications as a technique for creating protective and decorative coatings of metallic and non-metallic surfaces, protecting materials against corrosion at elevated temperatures in both alkaline environments and organic acid solutions, forming a sublayer for obtaining coatings of other metals on steel, enhancing the hardness and wear resistance of surfaces, as well as for improving solderability. Such coatings can be obtained from weakly acidic aqueous and weakly alkaline complex electrolytes. In this review, we analyze the available literature on complexation of nickel(+2) with D-gluconate ion CH2OH(CHOH)4COO‾, along with that on compositions and some technological characteristics of complex D-gluconate solutions for nickel electrodeposition and electroless plating. Thus, a corrosion-resistant smooth light-colored nickel coating, tightly adhered to a copper substrate, was obtained from an electrolyte with a pH level of 8, containing 53 g/dm3 of NiSO4 •6H2O, 44 g/dm3 of D-C6H11O7Na, 25 g/dm3 of H3BO3, 53 g/dm3 of (NH4)2SO4, and 0.5–3 g/dm3 of CO(NH2)2, at a temperature of 25 °C, a cathodic current density of 2.5 A/dm2 with a current efficiency of 96.4%. An electroless Ni-P(3–18 wt%) alloy coating on copper was obtained from a solution with a pH level of 9, containing 5–30 g/dm3 of NiSO4 •6H2O, 10–60 g/dm3 of D-C6H11O7Na, 5–40 g/dm3 of NaH2PO2 •H2O, 3 g/dm3 of HOOCCH2CH2COOH, 0.5 g/dm3 of CH3(CH2)11OSO3Na, 0.002 g/dm3 of Pb(CH3COO)2•3H2O, at a temperature of 90 °C and a deposition rate of up to 0.75 μm/min. The review also discusses methods for preparing D-gluconate electrolytes for nickel plating using sodium D-gluconate, D-glucono-1,5-lactone, and nickel D-gluconate. One advantage of D-gluconate nickel plating solutions consists in the absence of toxicity and low cost of D-gluconates.

Information-bibliographical service of scientific and technical problem of „Application of protective coatings as well as protective and decorative metal coatings"

The article is devoted to the analysis of information models dealing with the problem of the application of protective coatings as well as protective and decorative metal coatings. Results of investigations reveal the subject structure of the problem, display the core of scientific and industrial journals, and define bibliographical manuals and databases. Based on the developed models, a structure for a problem-oriented data bank is suggested.

Neutron and X-ray Scattering Characterization of Silica Nanoparticle-Stabilized Polymer Hybrid Latex Particles.

A robust route to produce poly(methyl methacrylate) (pMMA) hybrid latex particles (radius ∼250 nm) that are selectively "armored" with silica nanoparticles (radius 12.5 nm) through addition of vinyltriethoxysilane was previously shown ( J. Colloid Interface Sci. 2018, 528, 289-300).Depending on synthesis conditions, the extent of nanoparticle attachment could be varied; however, the mechanism behind this attachment during latex growth remained unclear. The dual population of particles present (silica + polymer) means that particle sizing by dynamic light scattering is ambiguous. Furthermore, the low glass transition temperature (Tg) of polymers such as poly(butyl acrylate) (pBA) typically used in film-forming applications for decorative coatings (i.e., paints) means that the hybrid latex particles are too "soft" for robust analysis through atomic force microscopy (AFM) and scanning electron microscopy (SEM). Here, we show that small- and ultrasmall-angle neutron scattering (SANS and USANS), along with complementary data from small-angle X-ray scattering (SAXS), reveals that these armored hybrid latex particles adopt a raspberry-type configuration, supporting their core-shell structure. The number of nanoparticles present on the surface of the hybrid latex can be adjusted by addition of one of a diverse range of alkyl- or perfluoroalkyl-silanes to alter silica nanoparticle hydrophobicity, and quantified through analysis of scattering data. The approach therefore provides a novel, nonperturbative, and in situ method of quantifying nanoparticle attachment to polymer latex particles.

Spectroscopic analysis of color origins in titanium-based thin films deposited by cathodic arc deposition

The distinctive colors observed in titanium-based (Ti-based) decorative coatings fabricated by cathodic arc deposition originate from the unique electronic, morphological, and chemical properties of these films. Most Ti-based film colors arise from their surface band gaps, as measured by electron energy loss spectroscopy, with the exception of the lowest brightness (TLB) and green hues. The green color in titanium dioxide films typically results from interference between light reflected from the film and substrate interfaces. In contrast, the black color in Ti-based coatings stems from the chemical structure, specifically the presence of Ti-C and C=C(sp2) bonds within the film. Moreover, the large band gap of the TLB film surface is attributed to surface oxidation, as detected by soft X-ray spectroscopy. Significantly, the film thickness and surface roughness are characterized by field emission secondary electron microscopy and atomic force microscopy, respectively.

A robust, durable and eco-friendly UV-cured wood film with self-matting and anti-fingerprint performance via wrinkled structure

With the changes in people's living standards and aesthetic perspectives, the matting films with wrinkled surfaces play a crucial role in fields such as decorative materials, wooden furniture, wood-based panels and industrial coatings. In this paper, the UV-cured polyurethane acrylate (PUA) films with self-matting and anti-fingerprint performance on the wood-based panels was prepared and developed the wrinkled surface by using excimer/mercury dual UV curing. The results showed that the roughness, wavelengths (λ) and amplitudes (A) of wrinkles surface were positively correlated with the excimer irradiation time and negatively correlated with the mercury lamp irradiation time. Furthermore, the increasing irradiation time improved the degree of curing and crosslink density of the cured films, which enhanced the mechanical properties and durability of the cured film. Consequently, the prepared UV-cured PUA film exhibited excellent self-matting with a gloss of 3.4 GU at an incident angle of 60° and maintained the gloss value < 5 GU after 500 times rubs and 1 hour corrosion. Additionally, the self-matting films with wrinkled surface enhanced the hydrophobicity and anti-fingerprint performance of the surface. Besides, the cured film presented high physical performance with hardness of 4 H and adhesion of 0 grade. These results provide a reference for the further application of self-matting films in wood-based panels, furniture and interior decoration fields.

PVD decorative coatings on polycarbonate and polyamide substrates for the automotive industry

Utilizing magnetron sputtering to incorporate metal onto polymer surfaces as a substitute for metal parts in the automobile industry offers an eco-friendly alternative. In this work, decorative titanium oxynitride (TiNxOy) coatings were sputter deposited over polycarbonate and polyamide 12 substrates using a low-temperature pulsed deposition method. In order to improve coating adhesion, all substrate surfaces were pre-treated for 30 s by reactive plasma etching. Four different film thicknesses were investigated to achieve various colours. The TiNxOy coatings were quasi-amorphous, and the oxygen content decreased with increasing film thickness. Overall, four distinct colours - green, purple, magenta, and blue - were produced, and all coatings showed excellent adhesion to the polymeric substrates. Colour fastness was assessed using adapted pin-on-disk tests to evaluate the film's applicability as decorative coatings for automotive parts, with all films achieving high ratings for colour fastness. This study provides insights into the deposition of thin films on polymeric substrates, showcasing successful approaches to achieve desired colours while preserving the film's optical properties after color fastness testing.

Electrochemical deposition of coloured Ni/Cu2O bilayer films on large area plastic substrates for decorative applications

ABSTRACT In this study, coloured Ni/Cu2O bilayer films were electrochemically deposited on large area automobile plastic parts (7 × 13 cm) for decorative applications. Such coatings may become an alternative to ubiquitously used Cr coatings for plastics. Purple, dark cyan and gold colours with good homogeneity and high brightness could be produced by tuning the deposition time of the Cu2O layer. Colouration of the bilayer film can be ascribed to interference of light through the metal/dielectric layer, where the thickness of the dielectric layer controls the wavelength of the reflected light. Cu2O film has a compact structure and low roughness, which is essential to obtain uniform colours. Moreover, the Ni/Cu2O bilayer exhibits good adhesion behaviour, environmental stability and enhanced corrosion resistance. This process is industrially viable and enables the large scale production of such decorative coatings.

Influence of Multilayer Structure on the Structural and Mechanical Properties of TiAlN/CrN Coatings for Advanced Machining Applications

This study investigates single and multilayer TiAlN/CrN nanocomposite thin films developed using an RF magnetron sputtering system. The TiAlN and CrN layers showed a high degree of orientation, with the (200) peak being the strongest peak in both layers, and a multilayer structure was clearly observed. The surface roughness analysis using atomic force microscopy (AFM) and cross-sectional transmission electron microscopy (TEM) revealed that the TiAlN/CrN coatings had a smoother surface than the single-layer coatings and minimal intermixing between the two layers. Depth-sensing indentation measurements were used to measure the hardness and Young’s modulus of the coatings, demonstrating that TiAlN/CrN coating had the highest hardness (~16.38 GPa) and elastic modulus (~3.82 GPa) among all the coatings studied. This indicates that the TiAlN/CrN multilayer coating possesses superior mechanical properties due to its interface strength. Our findings suggest that these multilayer coatings have potential applications in tribological and decorative coatings.

Influence of Additives on the Macroscopic Color and Corrosion Resistance of 6061 Aluminum Alloy Micro-Arc Oxidation Coatings.

In this study, we successfully employed the plasma electrolytic oxidation (PEO) technique to create a uniform white ceramic layer on the surface of the 6061 aluminum alloy using K2ZrF6 and Na2WO4 as colorants. A scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectrometer (EDS) and X-ray diffraction (XRD) were used to characterize the coatings, and we used an electrochemical workstation to test their corrosion protection properties. The corrosion resistance of the coatings was analyzed using potentiodynamic polarization curves. The results showed that K2ZrF6 addition whitened the coating with ZrO2 as the main phase composition, inhibiting Al substrate depletion and enhancing coating corrosion resistance. A small amount of Na2WO4 decreased the coating's L* value, successfully constructing ceramic coatings with L* (coating brightness) values ranging from 70 to 86, offering broad application prospects for decorative coatings.

Reducing the incorporation of contaminant oxygen in decorative TiN coatings deposited by low temperature reactive sputtering

This paper focuses on the low-temperature deposition and characterization of titanium nitride coatings. It investigates how the deposition conditions influence the incorporation of contaminant oxygen and the functional properties of the coatings. The coatings were reactively sputtered in an Ar + N2 atmosphere under two different substrate conditions: floating and bias modes. The target poisoning process was studied by selecting different N2 flow rates. The Ti/N ratio and the contaminant concentration varied greatly with the N2 flow rate and substrate bias condition. Both the Ti/N ratio and oxygen inclusion produced important modifications in the structural, chemical, optical and electrical properties of the TiN coatings. Samples deposited in floating mode showed oxygen contents up to 25 at.%, and TiN crystals that were preferentially oriented along the [111] and [110] directions. These coatings exhibited dark brownish colorations. Samples deposited in bias mode showed reduced oxygen contents between 6 and 12 at. % and promoted the crystallization of TiN with the [110] preferential orientation. These coatings presented bright yellowish colorations. By sputter depositing TiN coatings at low substrate temperatures, under appropriate deposition conditions, the desired decorative properties can be achieved while preserving the integrity of sensitive substrates, such as polymers.

A Review of Protective and Decorative Coatings on Polyester Fabrics

Fabrics are widely used in non-clothing applications such as construction, transportation, healthcare,electronics, sports, etc. Due to its remarkable mechanical qualities, including high tensile strength, abrasionresistance, and dimensional stability, polyester textiles are frequently employed in a variety of applications.Unfortunately, they are prone to poor breathability, water resistance, and other functional issues. In orderto address these issues and improve the functional performance of polyester textiles, coating technologieshave been developed. By adding new functional groups, nanostructures, or chemical treatments, coatingshave the power to change the attributes of surfaces, enhancing things like water repellency, breathability,antibacterial activity, UV resistance, and other desirable qualities. The aesthetic appeal of polyestermaterials may also be enhanced by coatings by adding distinctive colour, texture, and print patterns.Protective coatings can help to increase the resilience of polyester textiles to various environmentalconditions. Decorative coatings can be used to give polyester fabrics an aesthetically appealing surfacefinish. The purpose of thisreview isto offer a comprehensive overview of modern protective and decorativecoatings for polyester fabrics. This review explores the benefits and downsides of each coating and assessestheir impact on the physical and mechanical attributes of polyester textiles, such as colourfastness, tensilestrength, and wear resistance. Overall, it has been determined that additional study is required toinvestigate the different uses that polyester textiles may serve.

Numerical solutions of thin film flows of non-Newtonian fluids via optimal homotopy asymptotic approach

The objective of this research is to recover new solutions in the lifting and drainage cases of thin film flows involving non-Newtonian fluid models namely Pseudo-Plastic (PP) and Oldroyd 6-Constant (O6C). Both of the considered fluids exhibit numerous uses in industry when coupled with thin film phenomena. Some of the industrial applications include decorative and optical coatings, prevention of metallic corrosion and lithography of various diodes, sensors and detectors. For solution purpose, a modified version of Optimal Homotopy Asymptotic Method (OHAM) is proposed in which Daftardar–Jafari polynomials will replace the classical OHAM polynomials in nonlinear problems and provide better results in terms of accuracy. The paper includes a comprehensive application of modified algorithm in the case of thin film phenomena. To validate the obtained series solutions, the paper employs a rigorous assessment of convergence and validity by computing the residual errors in each scenario. For showing the effectiveness of modified algorithm, numerical comparison of classical and modified OHAMs is also presented in this study. Furthermore, the study conducts an in-depth graphical analysis to assess the impact of fluid parameters on velocity profiles both in lifting and drainage scenarios. The results of this investigation demonstrate that the proposed modification of OHAM ensures better accuracy of solutions than the classical OHAM. Consequently, this method can be effectively utilized for tackling more advanced situations.

Application of Secondary Ion Mass Spectrometry for Analysis of Decorative Coatings on Fancy Goods Accessories

The results of a secondary ion mass spectrometry (SIMS) study on Ag and ZrN decorative coatings on nickel and white bronze substrates for fancy goods accessories are presented. It was found that for Ag coatings, an intense diffusion of Cr from the adhesion layer between the coating and the substrate is observed, and corrosion testing in an acetic salt (CH3COOH+NaCl) atmosphere leads to the almost complete degradation of such coatings. ZrN coatings on white bronze turned out to be the most resistant to Cr diffusion and corrosion processes.

DECORATIVE COATINGS AND METALS IN JEWELLERY AND ART PRODUCTS

The article considers the classification of precious and non-precious alloys used in the manufacture of jewellery and art articles. Alloys are considered from the point of view of necessity of using protective and decorative coatings both for protection from environmental impact during operation of articles and colour surface decoration. A diverse nomenclature of various metallic, non-metallic and conversion coatings formed by different technological methods is shown. It is shown that the use of a certain coating is largely determined by the designer at the stage of creating a rendering of the product. Necessity to take into account the colouristic characteristics of alloys and coatings at the design stage and the existence of an inseparable connection between the product design, materials used, technologies of their shaping and decoration is pointed.

Ag Behavior on TiN Thin Films for Decorative Coatings

TiN-Ag ceramic coatings deposited by magnetron sputtering on silicon wafers and AISI F138 stainless-steel substrates with different Ag concentrations were evaluated for their application as decorative coatings. The results obtained indicated an almost linear increase in the thickness and roughness of the film as a function of the increase in the silver content of the film. For Ag concentrations greater than (8.3 ± 0.5) at %, a matte/satin finish was observed, i.e., a dull surface, produced by the agglomeration of particulates and the increase in roughness, respectively, which was corroborated by SEM and AFM analyses. The EDS analyses indicated particles with a high concentration of silver, but the elements titanium and nitrogen were also observed, indicating the formation of the TiN-Ag coating. The L*a*b* parameters in the CIELab color space were evaluated. No major variations were observed for coatings A and B (Ag concentrations of (4.1 ± 0.4) and (6.3 ± 1.2) at %, respectively). When the Ag content increased substantially, there was a corresponding decrease in L* values, as well as a shift in red reflectance. Furthermore, unwanted changes in the visual appearance and resistance to accelerated corrosion (salt spray) were also analyzed, as these factors compromised the film’s aesthetics in decorative applications.

ЗАВИСИМОСТЬ ДЗЕТА-ПОТЕНЦИАЛА ПЛЕНКООБРАЗОВАТЕЛЯ НА ОСНОВЕ НЕОТВЕРЖДЕННОГО КАЛИЙ-НАТРИЕВОГО ЖИДКОГО СТЕКЛА ОТ КОНЦЕНТРАЦИИ ЕГО СОСТАВЛЯЮЩИХ

One of the important tasks of modern production is the development of such finishing protective and decorative coatings that do not adversely affect the environmental situation. In this connection, the market reorientation from organically dilutable paint and varnish materials to water-based paint and varnish materials is becoming more and more obvious. Such paint and varnish materials for protective and decorative purposes include paints produced on the basis of liquid glass. On the basis of liquid glass are produced silicate facade paints with improved performance and fire protection properties, which are resistant to ultraviolet radiation and sharp temperature changes, they are more durable, environmentally friendly, they have a lower cost compared to acrylic, polyvinyl acetate, water dispersion paintwork materials. At present in scientific and technical literature there are numerous publications devoted to silicate coatings on concrete, ceramic surfaces, paving slabs, slate. However, despite the large number of patented formulations, there are no publications on the coating composition-colloidal properties relationship in the periodic literature. In the present study, the zeta potential of film formers based on potassium liquid glass and latex, potassium-sodium liquid glass and latex was determined to determine the stability of uncured solutions. The studies were carried out using a dual angle particle size analyser Zetasizer Nano ZS, Malvern. The measurements were performed in a U-shaped cuvette with gold electrodes at pH = 7.4 and temperature 25oC. As a result of experiments it was found that the most stable are uncured film formers based on potassium liquid glass and latex with the addition of sodium liquid glass. The developed recommendations will allow manufacturers of silicate paints to improve their quality with simultaneous reduction of production cost.

Effectiveness of the using powder coating for protection of metal construction

Сurrent state of the Ukrainian economy causes to resolve a range of questions related to the improvement of production and increase in the ecological safety of products, including paint-and-varnishes materials, in combination with ensuring high operational properties of coatings based on them. This questions can be solved by scaling up production using eco-friendly powder coating. The increase in popularity of powder coatings can be explained by their environmental adequacy and attractiveness from the perspective of the environmental protection as well as high effectiveness related to the possibility of obtaining high quality protective and decorative coatings with the high corrosion and chemical resistance as well as controllable physical and mechanical and dielectric characteristics during the one-layer application. The analysis of research results shows that the effectiveness of use of metakaolin and talc as fillers in the powder coating increases in proportion to their content in the system. The optimal area of the powder coating with metakaolin and talc is limited to the additive in the range of 20 to 30 % and polyester resin in the range of 55 to 65 %. Using the mentioned range of fillers in the powder coating contributes to the decrease in the peeling width and metal corrosion width and places the coating into atmospheric corrosivity categories С3 and С4 according to ІSO 12944-2:2017 having a high (Н) lifespan from 15 to 25 years in accordance with DSTU ISO 12944-1 In this case, one of the most common methods of influence on properties of paint-and-varnishes coatings is to create polymer composites by combining polyester raw materials with inorganic fillers.

Effect of ytterbium on hardness and color of titanium nitride thin films

Yb mononitride (YbN) has a B1 (NaCl-type) structure similar to the structure of titanium nitride (TiN), which makes it a candidate for use in new hard coating materials via solid-solution hardening. Ternary system (Ti–Yb–N) thin films with various Yb contents were prepared on Si substrates by pulsed laser deposition, and compositional analysis confirmed that the resultant films contained the expected elements. Phase identification revealed that the ternary nitride (Ti1−x Yb x )N thin films were all single-phase thin films that comprised YbN in TiN as a solid solution in the form of a B1- (Ti1−x Yb x )N phase. Although the hardness of the Ti–Yb–N thin films could be increased to a certain degree compared with that of a pure TiN thin film, the improvement was not significant. A change in the optical properties of the (Ti1−x Yb x )N thin films was indicated by a change in their color from gold to copper to silver with increasing x. This effect could make such thin films suitable for use as decorative coatings that are resistant to oxidation.

Implementing miniemulsion photopolymerization for synthesis of waterborne biobased poly(thioethers) coatings

Herein, miniemulsion photopolymerization is implemented as a useful tool for synthesis of waterborne poly(thioether) dispersions from biobased monomers isosorbide-based dithiol (3R,3aR,6S,6aR)-hexahydrofuro[3,2-b]furan-3,6-diyl bis(3-mercaptopropanoate) and diallyl (3R,3aR,6S,6aR)-3,6-bis(allyloxy)hexahydrofuro[3,2-b]furan and their combination with the petroleum-based dienes diallyl terephthalate, 3,9-divinyl-2,4,8,10-tetraoxaspiro [5.5]undecane, and 1,4-bis(allyloxy)benzene. The synthetic process is optimized to achieve 30 % solids content latexes with weight average molecular weight ranging from 8.2 kg/mol to 136 kg/mol. The resulting poly(thioether) latexes yield consistent continuous polymer films after water evaporation at atmospheric conditions. Poly(thioether) films based on both biobased thiol and ene are soft and sticky, and thus, present insufficient mechanical properties for coating application. On the other hand, when biobased thiol was combined with petroleum based enes with aromatic and cyclic moieties within the structure, the obtained films are rigid and film forming. Only the film based on diallyl terephthalate diene present excellent balance of stiffness and flexibility, therefore with potential for coating application. Moreover, this film shows relatively good water sensitivity, with water uptake below 20 % after 11 days of water immersion and high gloss (above 80 gloss unit) measured at 60° angle of incidence. The properties are within the range of requirements for decorative coatings applications.