Bright Shades Research Articles

Evolution of red ceramic pigments: from hazardous compounds to environmentally friendly alternatives

Synthesis of red ceramic pigments is a challenging task in the ceramic industry. Most classic reds are based on severely toxic materials including lead, arsenic, mercury, selenium, and cadmium, which are forbidden in many countries. On the other hand, the red color is super sensitive to the synthesis parameters, heat treatment conditions (atmosphere and temperature), particle size, etc. Therefore, achieving a bright true red shade and its stability at high temperatures is crucial. There has been a massive attempt to find a sustainable high-temperature resistant alternative for these hazardous compounds. Iron oxide is one of the first red pigments in history, but it cannot produce a bright red shade and its color is mostly red-brown. Ce2S3 is another red pigment with a beautiful red color. But it cannot stand the temperature above 350 °C in an oxidizing atmosphere. Doping lanthanides in the perovskites or entrapping the toxic beautiful chromophores in the core-shell structures are among the strategies to achieve safe bright red pigments. This review outlines the recent progress of hazardous classic reds to environmentally friendly ceramic red pigments. Various compounds and dopants, applied to develop sustainable reds, from simple iron-oxides to composites, solid solutions, core-shell structures, or even purified wastes have been covered in this review.

Abstract Art as an Inspiration to Create Textile Patterns through Computer Aided Designing

Art breaks away from the traditional representation of everyday objects and familiar subjects. The viewer is not distracted by meaningful images, so the mind is stirred into felling the energy and spirit of a design. Art does not reflect any form of realism, in fact, it breaks the rules. This study aimed at creating unique patterns for textiles through computer-aided design by taking abstract art as a source of inspiration. It was completed in three phases. First phase comprised of a selection of various inspirational themes from Abstract Art. In the second phase, an experimental approach was taken by developing various patterns through a range of colours and layouts to discover the best and most suitable for the end products. The created patterns were then applied to each category of apparel as 2D and 3D models through Adobe Illustrator and Adobe Photoshop. In the third phase, an online survey was conducted to investigate the market demand of consumers towards developed designs. The results showed that 60% respondents strongly appreciated the uniqueness of design, 56% respondents liked the colour scheme, and 62% of respondents preferred to have this design in their wardrobe. 57% respondents were strongly agreed that the principles of design were well balanced. It was concluded that Marbling Abstract art becoming more popular pattern for apparel due to its bright colour shades, different lines and triangle shapes which attract the participants. The study will be beneficial for the textile designers to opt for multiple categories from abstract art for developing patterns in apparel.

The Pink World of Prudence Flint

Prudence Flint is a female painter living and working in Melbourne, whose paintings are characterized by extremely bright pastel shades and slightly exaggerated female nudes. The gentle serenity that is unique to women from a female perspective is brought out in her images. She portrays ordinary women in a variety of interior spaces, showing the beauty of their bodies deliberately reshaped and sculpted, while the backgrounds are rendered with transcendent simplicity and comforting colors. This paper takes several key works of Flint's since her career and her oral interviews as references and explores how Flint's attitude towards patriarchal society is expressed through the manifestation of "femininity" in her paintings, in combination with the theories related to Western dualism and feminist thinking.

Functionalization of wool fabric by rice stubble extract dyeing and bio-mordanting

In this research, rice stubble, an air-polluting agricultural waste after burning the current years, was considered to explore a sustainable application in rice-growing countries. The rice stubble extract was used to dye and functionalize the wool fabric. The dyed woollen fabrics were thoroughly characterized concerning their physical, chemical and comfort properties by scanning electron microscope (SEM), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, water vapor transmission rate (WVTR), and ultraviolet protection factor (UPF). The color characteristics, color fastness against the woollen fabrics, and flame retardancy were also assessed. The results revealed that the rice stubble extract has a coloring chromophore to offer bright shades with considerable fastness abilities. The rice stubble-dyed woollen fabrics showed considerable water vapor permeability, efficient UV shielding, and adequate flame Retardancy. The dyed woollen fabrics showed a maximum water vapor permeability of 2500 g/m2/24h, ultraviolet shielding of 350, and a limiting oxygen index of 30.

Influence of Ceramic Material Type and Cement Shade on the Translucency of Lithium Disilicate Ceramic Veneers.

Aims: Careful selection of materials and resin cement shade can minimize color changes in laminate veneers. This study aimed to evaluate the influence of two ceramic material types, lithium disilicate glass-ceramic material (Ivoclar, Schaan/Liechtenstein; IPS e.max), computer aided design (CAD) and IPS e.max Press, and four different resin cement shades on color changes in lithium disilicate ceramic laminate veneers. Methods: Forty extracted human maxillary first premolars were prepared to receive a laminate veneer. Optical scanning and digital designing were used to prepare 20 IPS e.max CAD and 20 IPS e.max Press veneer samples. These samples were divided into four groups based on resin cement shade and material: Group CAD A1 : (IPS e.max CAD with A1 cement shade), Group CAD T : (IPS e.max CAD with translucent cement shade), Group CAD M : (IPS e.max CAD with milky bright cement shade), Group CAD B1 : (IPS e.max CAD with B1 cement shade) and the same divisions for IPS e.max Press. Before cementation, color measurements were obtained using precision colorimeter NR110. After cementation, the ∆E (color change) value was recorded and tabulated. One-way analysis of variance (ANOVA) and Duncan's post hoc test were used to evaluate the influence of ceramic material types and cement shade on ∆E. Results: There were significant differences between the IPS e.max CAD and e.max Press veneers for the four tested cement shades. The highest color change was observed in press M veneers (8.84 ± 0.63931) while the lowest color change was observed in CAD M veneers (0.5 ± 0.16371). There were significant differences in color change based on cement shade, with B1 showing the greatest change (8.84 ± 0.47440 for Press veneers and 2.3 ± 0.11992 for CAD veneers). Conclusions: Different shades of resin cements and different manufacturing techniques produce different levels of color changes therefore careful selection of materials and cement shade can minimize color changes in laminate veneers.

High-quality maple genome reveals duplication-facilitated leaf color diversity

Acer truncatum is a horticultural tree species with individuals that display either yellow or red leaves in autumn, giving it high ornamental and economic value. 'Lihong' of A. truncatum is an excellent cultivar due to its characteristic of having autumn leaves that turn a bright and beautiful shade of red, while its closely related cultivar 'Bunge' does not. However, the molecular mechanism underlying the color change in the cultivar 'Lihong' is still unclear. Here, we assembled a high-quality genome sequence of Acer truncatum 'Lihong' (genome size = 688 Mb, scaffold N50 = 9.14 Mb) with 28,438 protein-coding genes predicted. Through comparative genomic analysis, we found that 'Lihong' had experienced more tandem duplication events although it’s a high degree of collinearity with 'Bunge'. Especially, the expansion of key enzymes in the anthocyanin synthesis pathway was significantly uneven between the two varieties, with 'Lihong' genome containing a significantly higher number of tandem/dispersed duplication key genes. Further transcriptomic, metabolomic, and molecular functional analyses demonstrated that several UFGT genes, mainly resulting from tandem/dispersed duplication, followed by the promoter sequence variation, may contribute greatly to the leaf color phenotype, which provides new insights into the mechanism of divergent anthocyanin accumulation process in the 'Lihong' and 'Bunge' with yellow leaves in autumn. Further, constitutive expression of two UFGT genes, which showed higher expression in 'Lihong', elevated the anthocyanin content. We proposed that the small-scale duplication events could contribute to phenotype innovation.

DYEING AT HOME FROM KITCHEN WASTE - TEA AND COFFEE RESIDUE

Food and Textile industries are considered to be the most vital industries for human survival. The food industry generates an enormous amount of waste which is used as animal feed or undergoes composting or just go as landfills. Some of these organic wastes contains colouring pigments which can be effectively used to colour textiles. Hence there is a possibility to bridge the gap utilizing the waste from food industry to colour textile materials. Chemical dyes are easier to use and produce bright shades but on the other hand it causes pollution to the environment. Natural dyes from plant sources are required in large amounts which may cause depletion of natural resources. Considering these factors, the waste material from food industry, which is available at little, or no cost can be effectively used to colour textiles, this would make natural dyeing affordable and bring about sustainability in textile dyeing process. This kind of sustainable approach protects the environment by utilizing the waste produced by one industry and creating a value-added item for another industry. This study was carried out considering the sustainability aspect which is mutually beneficial to food and textile industries.Natural dyes can be found in the kitchen or in one’s garden can produce beautiful hues. A simple dyeing process can be used to colour the fabric at home utilising available resources in the home kitchen. Decoction waste after extracting two widely used beverages - tea dust and filter coffee dust which are part of everyday kitchen waste were used for the study. Instead of these wastes going directly as landfills, dye was extracted prior to its disposal. Cotton fabric, mordanted with Alum, was dyed with the extracted dye. These dyed fabrics showed good to excellent colour fastness to perspiration, rubbing, washing, and pressing. Since these dyes are natural in origin, they are safe and eco-friendly. This study proves that throw-away kitchen waste can be utilized to extract dyes that can be used to create value-added products.

The Bright and Dark Shades of Transparent Conducting Perovskites: From Science to Global Market

From band theory of solids, it is well known that electrical conductivity and optical transparency are mutually exclusive properties. However, due to advancement in science and technology, controlled doping has allowed to merge these properties in few materials such as thin films, bulk oxides, conducting polymers and carbon-based materials and are collectively known as transparent conducting oxides (TCO) and transparent conducting films (TCF). Recently, this extraordinary property is also found in doped nano-perovskites and hence can further meets the diversified demand in the field of photovoltaics, LCDs, FETs, diodes, supercapacitors and many more. For such applications, doped perovskite TCOs have becomes highly important and cost effective for the future global markets. This paper will summarize the status and progress of various TCOs which are particularly perovskite in structure. Future direction and challenges of doped Perovskites in the techno-era are also discussed. Several examples of TCO-Perovskites are presented with a discussion of their ferroic, magnetic, electrical and optical properties. On addition, the concerns related to thermal and chemical stability of TCO-Doped Perovskites are vividly reviewed.

Dyeing of Cotton Knit Fabric with Natural Dyes Extracted from Java Plum

Natural dyes extracted from natural sources are likely to be less harmful and more eco-friendly than synthetic dyes. In this study, cotton fabric was dyed with natural dyes extracted from Java plum fruit ( Syzygium cumini). Dyeing was accomplished with or without mordanting agents using simultaneous and post-mordanting methods. The color of the treated substrates was investigated in terms K/S and CIELAB values. In addition, the attenuation co-efficient and solubility in organic solvents of the extracted dyes were determined. The wash and rubbing fastness of the dyed fabrics were good to excellent. Deep shades were obtained by post mordanting method with ferrous sulfate, whereas alum treated fabrics produced brighter shades with excellent fastness. Java plum fruit is available in many countries and offers a possible substitute for synthetic dyes.

Development of Sustainable Product Using Natural Dyes

Dyeing industry uses synthetic dyes as it gives brighter shades and also good fastness properties than natural dyes. But the water which comes aswaste from dyeing industry which consists of carcinogenic amines, which causes very series health hazards and spoils the environment. As a result, now natural dyes are becoming promising elements to develop natural and sustainable products.In this paper, it studiesabout fabric performance, durability and laundering properties of cotton and aloe-vera fabric dyed with natural dyes using Shibori dyeing technique and the dyed fabric have been used for various applications.

Sediment colour as recorder of climate and tectonics: Cenozoic continental red beds of the Himalayan foreland basin in NW India

The Cenozoic Himalayan foreland basin sedimentary facies are widely studied by researchers as they preserve record of complex interplay between tectonics, sedimentation and climate. Palaeoclimate reconstructions from these sediments have been done using various proxy tools. Colour of sedimentary facies is considered as one of the diagnostic palaeoclimate/climate indicator and the red colour is commonly associated to be with hot, arid climate. The Himalayan foreland basin (HFB) sediments from the oldest to the youngest, comprise almost all red and grey shades and the bright red facies greatly fascinate Earth Scientists. These red to grey coloured Himalayan foreland basin sediments preserve a record of global to regional climatic cycles and tectonic pulses. Studies pertaining to red colour and climate, specifically its association with hot, arid climate, are overwhelming. In general, studies focusing on continental red beds with specific climate are contradictory and confusing till date. Paradoxically, we now know more about red colour and climate than about red color and tectonics. Therefore, representative Himalayan foreland basin red beds of different times in the NW Himalaya have been selected for the present study. The HFB red beds of Oligocene, middle Miocene and upper Pliocene age have been investigated to find out any specific relationship of tectonics and/or particular climate cycles with red colour of these sediments on the basis of compilation of morphological, micromorphological, sub-microscopic and geochemical studies. It has been found that the bright red and grey colour shades are reliably shown by finer facies, particularly palaeosols, and coarser facies of the HFB sediments respectively, whether formed in cool, humid conditions or warm, arid conditions. This suggests greater role of tectonics during foreland basin sedimentation for preservation of sediment colour. Also, the purpose of this study is to highlight the need for more such investigations at various temporal and spatial scales in foreland basin sediments so that the colour of sediment can be appropriately used in future investigations dealing with sediment colour as an indicator of specific climate.

An Evaluation of Economic Prospects and Constraints of the Sundarbans - A Rising Tourist Spot in Khulna

Sundarban is the largest mangrove forest of the earth which covers almost 10000 square kilometers (3,900 sq. mi) in the Northern Bay of Bengal of which 6017 km2 (2323 sq ml) extended through the Khulna division of Bangladesh. Mangrove forests are extremely prolific and diverse ecosystems, providing a comprehensive array of direct ecosystem facilities for inhabitants. Dhaka & Kolkata is the most crowded cities in the world and Sundarban helps the people who lived in those cities from the different natural calamities like cyclone, strong disaster, and their worst effects. Bangladesh is a country where nature has exposed all its beauties. The aesthetic beauty of mountains, a unique ecosystem of the Sundarbans, the amity of mountains and clouds, bright shade of green trees and forests, the vastness of the sea, the world's longest sea beach, archaeological sites, religious places, ample tea gardens have brought the great potential for Bangladesh in the world tourism industry.Though the Sundarbans is one of the three world heritage sites in Bangladesh, it badly lacks proper tourist facilities. Proficient supervision of the tourist economy at any destination not only contributes to the visitors’ experience augmentation but supplements the opportunities available also and guards the atmosphere whilst safeguarding the interest of the host municipal and businesses functioning within it. The main purpose of this study was to find out how to develop the tourism economy in the Sundarbans effectively. Using a comparison with a high-quality visitor's gladness can be confirmed and the impact of tourism on Sundarbans’ atmosphere and to its host municipal can be accomplished.The study found, two main reasons are liable not to fostering the tourism economy in Bangladesh. The first one is the lack of resource constraints and the second is inadequate initiatives from the government to uplift (particularly infrastructural facilities) tourism in the country to make it known to prospective visitors in the world. The study recommends public and private investments and initiatives to foster the potential of the Sundarbans. Keywords: Sundarbans, World Heritage, Tourism Economy, Tourism Products, Growth Trend of Tourism, Public and Private Sector Initiatives Towards Tourism. DOI: 10.7176/RJFA/12-6-01 Publication date: March 31 st 2021

Comparison between nanohybrid filler and submicron composite resin shade on color changes after polymerization

Background: Initial color determination of composite resins before polymerization is crucial to achieve an esthetic result that mimics the original tooth color. A filler particle size and composition affect the color change of the composite resin after polymerization despite the improvement in the chemical composition and filler of the composite resin. Objective: The effects of nanohybrid filler and submicron composite resin shade on color changes after polymerization were determined. Methods: Disc-shaped composite resin samples (diameter and thickness of 12 mm and 2 mm, respectively) were categorized into six groups, with each group containing 10 plates, according to the shade and type of filler (nanohybrid UD1, UD2, UD3; submicron OA1, OA2, OA3). Digital photographs were taken before and after polymerization. The changes in color (ΔE*ab values) were determined using software via eLABor_aid. Result: Only the Micerium EHRi UD1 composite resin group exhibited ΔE*ab < 3.3. The independent t-test revealed significant differences in the ΔE*ab (P < 0.05) between the nanohybrid and submicron composite resins in all shade groups (A1, A2, and A3). One-way analysis of variance revealed significant differences in ΔE*ab (P < 0.05) among A1, A2, and A3 between the nanohybrid and submicron composite resin groups. Tukey’s post hoc test revealed significant differences in ΔE*ab (P < 0.05) for the Micerium EHRi UD1 group compared with those of the UD2 and UD3 groups, as well as in the case of the Tokuyama Palfique OA1 group compared with those of the OA2 and OA3 groups. Conclusion: Nanohybrid filler and submicron composite resin shade affected color changes after polymerization. Compared to the darker color groups, brighter shades (UD1 and OA1) exhibited a lower-intensity color change.

Enhancement of acid dyestuff salt-free fixation by a cationizing sol-gel based coating for cotton fabric

In the last years, several technologies have been investigated to introduce cationic sites onto cotton fibres to enhance anionic dyestuff uptake properties. However, several limitations of proposed technologies, such as fabric yellowing, high cost, inadequate reactivity, and toxicity of used chemicals, have still restricted the development of cationizing functional coatings. Herein, a new non-conventional sol-gel treatment of cellulose-based fabrics was investigated to introduce positive electrical charges as useful sites for binding acid dyestuffs, characterized by a featuring extensive colour range and bright shades. As proved by zeta potential and surface charge measurements as well as Fourier-Transform Infrared spectroscopy, the two-step procedure achieved using tetraethylorthosilicate (TEOS) and (3-Aminopropyl)triethoxysilane (APTES) sol-gel precursors promoted the functionalization of cotton fibres introducing amino groups, able to counteract the negative charge of cellulose during the dyeing procedure under acidic conditions. The dyestuff affinity for treated samples, compared to untreated cotton and polyamide references, was measured by competitive fixation of an acid dyestuff, namely Acid Yellow 114, from a non-electrolyte aqueous solution. The results showed that protonated amino groups, obtained at the highest APTES concentration, can reverse fibres charge enhancing anionic dye uptake properties without the addition of electrolytes. Compared to untreated cotton, the colour strength of cationized cotton was improved by nearly 90 %, depending on the APTES concentration, reaching performances obtained using a polyamide reference. The findings make sol-gel a reliable and promising method for cationizing cotton fibres for eco-friendly dyeing processes of cotton using acid dyestuffs.

한국 여성의 일상 상황별 계절에 따른 패션과 핸드백의 선호 색채

In this study, a survey sought to discern the preferred colors of fashion and handbags for millennial Korean women according to daily situations season. Several important insights were gained from the data. First, the preferred colors of millennial Korean women for fashion and handbags in daily situations were Red, Yellow Red, Yellow, and Purple Blue. In spring and summer, bright, vivid, and pale shades were preferred, whereas in fall and winter, dark, deep, grayish shades were preferred. Second, when selecting fashion and handbags for work, millennial Korean preferred the colors Y, YR, Y, and PB. Though there was a preference for brighter shades in spring and summer and darker shades for fall and, achromatic colors were preferable during all four seasons. When attending external meetings or giving a presentation, R, YR, Y, PB, W, and Bk were the preferred fashion and handbag colors. The results of the color analysis regarding complex situations revealed more insights. Unlike the other four situations, the preference of YR was relatively low when selecting a spring and summer top for a blind date, but the preference of G, BG, and PB was high, indicating that bright colors were preferred. The preferred colors for spring and summer tops in the context of meeting with close friends/self-development were YR, Y, W, and R. The preferred color for bottoms were Bk, GY, and YR. The preferred colors for handbags, beginning with the highest preference, were YR, Bk, Y, and R. This study can be a significant asset to the planning and image production of fashion and handbag companies by providing color data that identifies millennial Korean women’s preferences for colors based on the situation and season.

A new approach to flame‐retardant cellulosic fabrics in an environmentally safe manner

AbstractThis article investigates reacting potassium salts of phosphorous‐containing acids in the presence of urea with cotton cellulose under thermosol conditions (pH 5, 185 °C) to esterify the cellulose and produce a flame‐retardant effect. Attenuated total reflectance‐Fourier‐transform infrared (ATR‐FTIR) spectroscopy confirmed chemical modification of the cotton cellulose, where only the phosphite salt formed a covalently bonded cellulose ester (confirmed by flammability tests). Urea plays a vital role; decomposing to ammonia and isocyanic acid (the reactive intermediate) and it is the isocyanic acid/phosphite anion addition compound that reacts with cellulose hydroxyl groups to form the required ester. ATR‐FTIR analysis showed that phosphate and hypophosphite salts did not react with cellulose and thus gave no flame‐resist effect. Whilst the esterification of cellulose introduces phosphorous onto the cellulose, in order to meet more severe work‐wear laundry standards it was necessary to further incorporate a nitrogen species by addition of a cationic polymer. To develop a one shot “all‐in” process the possibility of simultaneously bonding nitrogen through carbodimide chemistry is researched, with initial promising trials demonstrated. Many after‐treatments of dyed fabrics can cause colour shifts due to interactions with the chromophores. Azo dyes, for example, are particularly susceptible to attack by the formaldehyde produced during the Pyrovatex process or the reducing nature of the Proban process, both resulting in a colour change. An advantage of the novel phosphite/urea flame‐retardant system presented herein, is that the system is less aggressive which allows the possibility of using reactive dyes to produce a bright and wide shade range as the results demonstrate.

Evaluation of Color Stability of Finix, Super Berelian and Betastar Acrylic Denture Teeth in Effect of Dentipur Denture Cleaner

Background: None of the previous studies have evaluated acrylic resin teeth used at the Dentistry Department of Hamadan University of Medical Sciences (brands: Finix, Super Berelian, and Betastar). Methods: A total of 252 samples containing acrylic resin teeth used at Hamadan Dental School were studied. Finix, Super Berelian, and Betastar were selected in the same mold and in 3 colors. (A1, A2, A3). The samples of each brand were studied in 2 groups. The first group was placed in a solution of Dentipur cleaner for 7 days. The second group of specimens was placed in 100 mL of distilled water. Data were recorded in the CIELAB system, and the spectrophotometer obtained values of ΔE, ΔL, ΔH, and ΔC. Then, changes in each of the components were obtained before and after the intervention. Results: The results show that the changes in the parameters of ΔE, ΔL and ΔC were statically significant when comparing the 2 groups (P < 0.05) and only in terms of the parameter ΔH, the changes were not statically significant (P > 0.05). The changes made in the variables were significantly different from the initial color of the samples in the factors ΔE, ΔL and ΔH (P < 0.001) but in terms of the parameter ΔC, the changes were not statically significant (P > 0.001), and the changes in the variables were significantly different from the sample brand in all the measured factors (P < 0.001). Conclusions: Dentipur denture cleaner creates more color change than distilled water in acrylic teeth. The changes in most variables were associated with the shade of acrylic teeth, and in the teeth with brighter shade, the color change was higher compared with a darker shade. Super Berelian teeth have the most color change and Betastar teeth showed the lowest change in color. Delta E value was clinically acceptable.

The use of poly(amido)amine dendrimer in modification of cotton for improving dyeing properties of acid dye

PurposeCotton being an anionic fiber can be dyed with direct, reactive, vat and sulfur dyes but cannot be dyed with acid dyes due to their chemical differences. But there are certain advantages of acid dyes like acid dyeing is the simplest method than the other classes of dyes; and it offers various intense and bright shades. So, the purpose of this paper is to focus on acid dyeing of cotton fabric after its chemical modification.Design/methodology/approachSuch modification of cotton fabric has been achieved using poly(amido)amine dendrimer (PAMAM) treatment. The current work is based on the synthesis of a full-generation PAMAM dendrimer (G0) and its application onto the cotton fabric for modifying the cotton substrate by the exhaust and padding method.FindingsThe treatment of the dendrimer on cotton fabric has been analyzed by Fourier transform infrared spectroscopy and scanning electron microscopy. The dyeing results in terms of color strength of the treated cotton fabrics are compared with those of conventional acid dyed silk fabric. The fastness assessments such as wash, light and rubbing fastnesses after dyeing of treated cotton fabrics are also performed and found to be satisfactory.Originality/valueThis paper can be used in the application of synthesized poly(amido)amine dendrimer in acid dyeing of cotton.

Dependence of Color of Clupak Paper Produced on Bleaching Level of Pulp Fiber

This research work deals with modification of the color of paper in commercial clupak dynamic image registration. According to the standard technology of production of kraft pulp, from which the production clupak paper, the paper obtained is dark brown in color. Market demand is based on quality and price of the product. Step further in these demands is demand for certain balanced and brighter shade of color of sack kraft paper. Lately it is demanded from our company to produce sack kraft paper with lighter shade of color. This problem can be solved in two ways: by coloring pulp fiber and by bleaching it. Methods of production of sack kraft paper with lighter shade, as well as results achieved, will be presented in this document.

Plasmonic color printing based on third-order gap surface plasmons [Invited

Metasurfaces for color printing rely on the resonant interaction of light with nanostructures, which translates to small physical resonator sizes for visible wavelengths, thus demanding very high fabrication accuracy that necessitates low-throughput processes and prevents the economical large-scale coloration and printing. Through the use of third-order gap plasmon resonances, element sizes necessary for visible resonances can be scaled to be compatible with several large-scale techniques for nanofabrication while retaining the capability of generating vivid colors. We demonstrate this using a 450-nm-periodic gold nanodisc array on SiO2 of different thicknesses (20, 40 and 50 nm) atop a thick gold substrate - a composite structure supporting gap plasmon resonances for both linear polarizations. A third-order resonance occurs for discs of 300 nm diameter and larger, while first-order resonances occur below 100 nm for red light (630 nm). By fabricating nanodiscs of different diameters, we observe vivid shades of red and green colors, with dark shades for third-order gap plasmon nanodiscs resonators due to inherent losses and bright shades for small discs of fundamental resonance counterparts. The third-order gap plasmon based nanodiscs are further spectrally characterized and tested for uniformity and reproducibility by demonstrating printed patterns. The significant improvement in both size and color range using the approach of higher-order based resonances can have a significant impact on the practical applicability and economic feasibility of plasmonic color printing.