Types Of Inks Research Articles

Enhancing Applicability of Reversible UV Thermochromic Offset Inks: Edge Quality Parameters and Thermochromic Printing System Modulation Transfer Function.

Modern logo design is characterized by its ability to convey information through the use of various images and text compositions. These designs often use simple elements such as lines to capture the essence of a product. When using thermochromic inks in logo design, it is important to consider their composition and behavior, as they differ significantly from conventional printing inks. This study aimed to determine the resolution capabilities of the dry offset printing technique when using thermochromic ink, with the ultimate goal of optimizing the thermochromic ink printing process. Horizontal and vertical lines were printed using both thermochromic and conventional inks to compare the edge reproduction characteristics of the two ink types. Moreover, the impact of the type of applied ink on the share of mechanical dot gain of the print was investigated. Additionally, modulation transfer function (MTF) reproduction curves were generated for each print. Moreover, scanning electron microscopy (SEM) was conducted to investigate the surface of the substrate and prints. It was found that the quality of the printed edge produced by thermochromic inks can rival that of conventional inks. Thermochromic edges showed lower raggedness and blurriness values for horizontal lines, whereas line orientation proved to be insignificant in the case of vertical lines. MTF reproduction curves confirmed higher spatial resolution for vertical lines in the case of conventional inks, whereas they were identical for horizontal lines. The share of mechanical dot gain is not highly influenced by the ink type. SEM micrographs confirmed that the conventional ink smooths out the micro-roughness of the substrate. However, on the surface, the microcapsules of thermochromic ink (measuring 0.5-2 µm) are observable.

Micro Raman spectroscopy combined with chromatographic effect and OPLS-DA for time-resolved detection of stamp inks

Ink type identification and ink formation time play a significant role in document examination. Current methods for dating stamp inks in questioned documents primarily rely on the analysis of volatile ink components. However, there is a dearth of literature on the investigation of ink distribution in the initial stages of stamp impressions. Such studies are scarcely reported, despite their potential significance in the field of forensic document examination. This study aims to explore the feasibility of ink diffusion based on Raman spectra monitoring and to identify the ink types using orthogonal partial least squares discrimination analysis (OPLS-DA) multivariate modeling. The kinetics of ink diffusion can be elucidated by the interplay of chromatographic effects and diffusion equilibrium. The diffusion boundary of the ink is visualized using a microscope, and 21 specific locations at varying distances from the boundary are designated for time-resolved spectrum acquisition. Typically, the diffusion process can be separated into two distinct phases an enrichment period followed by an equilibrium period. As the diffusion distance increases, the Raman peak intensity and ink concentration progressively diminish. Following the pre-processing of spectral data, any outliers were removed prior to utilizing the orthogonal partial least squares discrimination analysis method for classification purposes. The OPLS-DA model demonstrated 100% accuracy in differentiating between all types of stamp inks, affirming the significant potential of Raman spectroscopy for forensic science applications.

Characterizing different types of black fountain pen ink using the chemical approach

Fountain pen ink contains dyes, pigments, or nanoparticles as colorants; water and ethylene glycol or an organic solvent as the vehicle. The dyes in fountain pen ink are usually negatively charged acid dyes. In this study, various types of black fountain pen ink (5 dye-based and 5 nanoparticle-based) were investigated by ultraviolet–visible (UV–Vis) absorption spectroscopy, Ion Pair High Performance Liquid Chromatography Diode-Array Detector (IP-HPLC-DAD), Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS), and Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (LC-Q/TOF-MS) analysis. UV–Vis spectroscopy of fountain pen ink samples showed different profiles despite their similar color. MALDI-TOF-MS analyses successfully differentiated 10 of the inks. Nanoparticle-based ink, which is usually darker than dye-based ink, showed the same UV absorption at 240 nm. The use of LC-Q/TOF-MS, however, allowed the 5 dye-based fountain pen ink samples to be differentiated from one another. On the basis of the combined results of all analytical methods mentioned above, the discriminating power values were 0.71–1.00. Among them, MALDI-TOF-MS could successfully distinguish fountain pen ink samples with similar black colors and provide an easy analytical approach for the differentiation and identification of various types of fountain pens.

Transfer rates of Salmonella Typhimurium, Listeria monocytogenes, and a human norovirus surrogate impacted by macronutrient composition of food inks in 3D food printing systems

3D food printers (3DFPs) allow for the customization of the physiochemical properties of foods in new ways. Transfer kinetics of foodborne pathogens between surfaces and food inks have not been evaluated in 3DFPs. This study aimed to determine if the macromolecular composition of food inks would impact the transfer rate of foodborne pathogens from the stainless steel food ink capsule to the 3D printed food. Salmonella Typhimurium, Listeria monocytogenes, and a human norovirus surrogate, Tulane virus (TuV), were inoculated onto the interior surface of stainless steel food ink capsules and dried for 30 min. Subsequently, 100 g of one of the following prepared food inks was extruded: (1) pure butter, (2) a powdered sugar solution, (3) a protein powder solution, and (4) a 1:1:1 ratio of all three macromolecules. Pathogen enumeration was completed for both the soiled capsules and the printed food products and resulting transfer rates were estimated using a generalized linear model with quasibinomial errors. A significant two-way interaction effect was found between microorganism type and food ink type (P = 0.0002). Tulane virus was typically transferred the most, and no significant differences between L. monocytogenes and S. Typhimurium were observed for any food matrix or across food matrices. Among food matrices, the complex mixture transferred fewer microorganisms in all instances, while butter, protein, and sugar were all statistically indistinguishable. This research seeks to further develop the field of 3DFP safety and to advance the understanding of the role of macromolecular composition in pathogen transfer kinetics, which have not previously been explored in pure matrices.

Nanoimprinted 2D-Chiral Perovskite Nanocrystal Metasurfaces for Circularly Polarized Photoluminescence.

The versatile hybrid perovskite nanocrystals (NCs) are one of the most promising materials for optoelectronics by virtue of their tunable bandgaps and high photoluminescence (PL) quantum yields. However, their inherent crystalline chemical structure limits the chiroptical properties achievable with the material. The production of chiral perovskites has become an active field of research for its promising applications in optics, chemistry, or biology. Typically, chiral halide perovskites are obtained by the incorporation of different chiral moieties in the material. Unfortunately, these chemically modified perovskites have demonstrated moderate values of chiral PL so far. Here, a general and scalable approach is introduced to produce chiral PL from arbitrary nanoemitters assembled into 2D-chiral metasurfaces. The fabrication via nanoimprinting lithography employs elastomeric molds engraved with chiral motifs covering millimeter areas that are used to pattern two types of unmodified colloidal perovskite NC inks: green-emissive CsPbBr3 and red-emissive CsPbBr1 I2 . The perovskite 2D-metasurfaces exhibit remarkable PL dissymmetry factors (glum ) of 0.16 that can be further improved up to glum of 0.3 by adding a high-refractive-index coating on the metasurfaces. This scalable approach to produce chiral photoluminescent thin films paves the way for the seamless production of bright chiral light sources for upcoming optoelectronic applications.

3D Printing Technologies in Personalized Medicine, Nanomedicines, and Biopharmaceuticals.

3D printing technologies enable medicine customization adapted to patients' needs. There are several 3D printing techniques available, but majority of dosage forms and medical devices are printed using nozzle-based extrusion, laser-writing systems, and powder binder jetting. 3D printing has been demonstrated for a broad range of applications in development and targeting solid, semi-solid, and locally applied or implanted medicines. 3D-printed solid dosage forms allow the combination of one or more drugs within the same solid dosage form to improve patient compliance, facilitate deglutition, tailor the release profile, or fabricate new medicines for which no dosage form is available. Sustained-release 3D-printed implants, stents, and medical devices have been used mainly for joint replacement therapies, medical prostheses, and cardiovascular applications. Locally applied medicines, such as wound dressing, microneedles, and medicated contact lenses, have also been manufactured using 3D printing techniques. The challenge is to select the 3D printing technique most suitable for each application and the type of pharmaceutical ink that should be developed that possesses the required physicochemical and biological performance. The integration of biopharmaceuticals and nanotechnology-based drugs along with 3D printing ("nanoprinting") brings printed personalized nanomedicines within the most innovative perspectives for the coming years. Continuous manufacturing through the use of 3D-printed microfluidic chips facilitates their translation into clinical practice.

Conductivity model of graphene printed plates

A model has been developed to explain the dependence of the surface resistance of printed conductive graphene plates on their surface resistance. The model assumes that the printed conductive graphene plate is layered. The simulation results are compared with the experimental results obtained by the authors. The plates were printed with two types of ink: 1 -graphene ink. 2- graphene ink with polymer additives. The reliability of the approximation of experimental data on the surface conductivity of plates printed by the first and the second types is no worse than 99.5% and 98.5%. respectively. The model made it possible to estimate the effective thickness of graphene printed layers forming a conductive graphene plate. The mechanism of layer conduction is considered.

Copper(i) iodide organic–inorganic hybrid luminescent inks for anti-counterfeiting application

Copper(i) iodide incorporated organic–inorganic hybrid coating materials represent as a new type of solvent-free anti-counterfeiting inks.

Preliminary Study on the Fabrication of Multi-Layer Screen-Printed Electrode for Biosensor Application

ytical device that combines certain biological and physical elements. Several types of transducers are used for physical elements, such as optical, electrochemical, thermic, or gravimetric. Nowadays, electrochemical transducers have become widely used for the application of biomedical sensors. Electrochemical measurement devices called screen-printed electrodes (SPEs) are created by printing several types of ink on a ceramic or plastic substrate. SPEs enable speedy in-situ examination with high repeatability, sensitivity, and accuracy. In this study, SPEs were fabricated using a personalized CNC machine

Consecutive Ink Writing of Conducting Polymer and Graphene Composite Electrodes for Foldable Electronics-Related Applications.

For foldable electronic devices of the future, most components should have very good flexibility and reliability to maintain electrical properties even under repeated deformation. In this study, two types of inks for conducting polymer and graphene were simultaneously printed on flexible plastic substrates via the newly developed consecutive ink writing (CIW) process for the formation of composite electrodes of foldable electronic devices. To consecutively print conducting polymer ink and graphene ink, a conventional three-dimensional (3D) printer was modified by installing two needles in the printer head, and the two inks were printed through the nozzle in the same route with a time interval. By adjusting several printing conditions (ink concentration, printing parameters, printing time intervals between the two inks, etc.), various structures of composite electrodes, such as layered or fused 2D or 3D structures were developed on the glass substrate. Furthermore, by changing the printing order of the two inks and 3D printer bed temperature, the composite electrodes with a higher printing resolution were successfully printed on the flexible polyimide substrate. The printed composite electrodes via CIW process exhibit the lowest surface electrical resistance of 0.9 kΩ and high flexibility, and stable resistance values were maintained after 1000 cycles of the folding test. Consequently, the CIW process developed in this study applies to the production of the electrical parts and components for various flexible devices, such as foldable and wearable electronics.

Investigation of aerosol droplets diameter generated in aerosol jet printing

Abstract Aerosol jet printing is a contactless direct-write technique that could be used for the deposition of a variety of materials. First, used for electric paths, the technology was explored for many applications. The substantial part of the process is the generation of aerosols. The size of the droplets and the stability of the process affect the quality of the sprayed lines. This article investigates the diameter of the sprayed droplets, allowing future comparison of the results with sprayed lines. Droplets from ultrasonic and pneumatic generators were sprayed at their outlet on the polyethylene terephthalate (PET) foil. Using a digital microscope and the built-in algorithm, the diameter of the droplets was measured, and the dataset was collected as CSV files and served as a background to the box plot. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) scans were applied to verify the results obtained. The ink parameters used in the process have an influence on the aerosol generation and droplet diameter, whereas the carrier gas pressure has an impact mostly on the droplet diameter. In this case, the aerosol was produced from three types of ink in combination with two generators. For inks with a dynamic viscosity below 6.5 m·Pa−1·s−1 a stable range of 5–10 μm droplet diameter was observed. A high-viscosity ink (7.5–10.5 m·Pa−1·s−1) produced droplets with diameter in the range of 6–25 μm. The diameter of the droplet decreased from 7–22 μm to 1–5 μm with a reduction in the dynamic viscosity from 7.5–10.5 m·Pa−1·s−1 to 4.5–5.5 m·Pa−1·s−1.

Comparison of preprocessing and machine learning methods for identifying writing inks using mid-infrared hyperspectral imaging and machine learning

We compared preprocessing and machine learning methods for identifying writing inks on paper using mid-infrared hyperspectral imaging and machine learning. We collected training data by making a blackened circle on paper with a pen and measuring it using hyperspectral imaging. We attempted to identify-five types of black ink that are difficult to identify using visible and near-infrared spectroscopy and can only be identified using mid-infrared spectroscopy. We initially analyzed the spectra using principal component analysis, and used the scores as a substitute for the spectrum. As an overall trend, standardization of the data for each variable had little effect on improving the discrimination rate. By contrast, using the difference spectrum from the average spectrum of the paper was effective for improving the discrimination rate. The discrimination rate was higher for the second-order derivative than for the spectrum itself, and for the first-order derivative than for the second-order derivative. Furthermore, the combination of the three had the highest discrimination rate. We tested three supervised machine learning methods: decision trees, discriminant analysis, and k-nearest neighbors. The highest classification accuracy (97.6%) was obtained for second-order discriminant analysis. Considering the discrimination rate and learning time, second-order discriminant analysis was the best method. For the measurement data of a sample with blackened circles using all the writing inks, this method identified the different inks quite well. For the measurement data of crossed line samples, using the proposed method, we clearly identified each ink. At the intersection of two lines, the line written later was detected more strongly.

Functional Ink Formulation for Printing and Coating of Graphene and Other 2D Materials: Challenges and Solutions

The properties of 2D materials are unparalleled when compared to their 3D counterparts; many of these properties are a consequence of their size reduction to only a couple of atomic layers. Metallic, semiconducting, and insulating types can be found and form a platform for a new generation of devices. Among the possible methods to utilize 2D materials, functional printing has emerged as a strong contender because inks can be directly formulated from dispersions obtained by liquid‐phase exfoliation. Printed graphene‐based devices are shifting from laboratory applications toward real‐world and mass‐producible systems going hand in hand with a good understanding of suitable exfoliation methods for the targeted type of ink. Such a clear picture does not yet exist for hexagonal boron nitride (h‐BN), the transition metal dichalcogenides (TMDs), and black phosphorous (BP). Rather, reports of applications of these 2D materials in printed devices are scattered throughout the literature, not yet adding to a comprehensive and full understanding of the relevant parameters. This perspective starts with a summary of the most important features of inks from exfoliated graphene. For h‐BN, the TMDs, and BP, the characteristic properties when exfoliated from solution and strategies to formulate inks are summarized.

문서 감정상 볼펜 필획의 잉크 밀집도 및 너비 특성

The purpose of this study was to confirm the possibility of using the ink stroke density and width as a non-destructive analysis factor for estimating the ink and ball size of a ballpoint pen in the field of identification of writing instruments for document evaluation. The density and width of strokes were measured by applying a constant pressure (100-300 g) to a total of 39 ballpoint pens of 4 types of ink (oil, low-viscosity oil, gel and water) and ball size (0.5-1.0 mm). As a morphological characteristic of stroke density, it was confirmed that there were four types: 1) Selective diffusion of high-viscosity ink, 2) Agglomeration, 3) Dot, 4) Selective diffusion of low-viscosity ink. The deposition value of ink stroke density showed a tendency to be measured twice as low for oil (33.74~47.26%) with high viscosity compared to gel (78.19~84.66%) and water (44.96~85.26%) with low viscosity of ink. The stroke width showed a tendency to increase as the pressure applied to the ballpoint pen and the size of the ball increased. The stroke width according to the ink was similar in the case of oily and low-viscosity oils, but in the case of neutral, it was about 100 μm higher than that of oil and low-viscosity oils. As a result, the density and width of strokes showed a difference in the characteristics that appeared according to the viscosity of the ink. In the order of non-destructive analysis for the identification of writing instruments, it is necessary to ① analyze the deposit shape and deposit value of ink stroke density, and ② to estimate the ink and ball size through ink width measurement. It was confirmed that it can be used.

Application of absorption of infra-red radiation and reflection spectra to distinguish different inks of same color in alteration

The main aim of this study is to introduce non-destructive method to distinguish different types of ink of same color. In our daily life, we face many problems of alteration of genuine documents. Such alteration is done by using same color of ink as used in the document. It is not possible to differentiate the altered part by our naked eyes. There are many methods, destructive as well as non-destructive methods, to solve the problem of alteration. We have discussed the non-destructive method using Video Spectral Comparator (VSC)-6000. Analysis is carried out with application of infra-red (IR) radiation of different wavelength and reflection spectra to reach the conclusion. Absorption of infra-red (IR) radiation is found very effective whereas use of reflection spectra is totally failed in this experiment. BIBECHANA 19 (2022) 34-39

KECEPATAN PROSES CETAK MOTOR DC MESIN OUTDOOR TERHADAP KEPUASAN KONSUMEN PADA PT. SEMBURAT LENTERA SEMESTA

Outdoor Digital Printing Machine is a printing machine or digital printing machine whose printouts are intended for outdoors and are weather-resistant, both hot, sunlight and rain. Outdoor machines use a special type of ink, namely solvent ink. The principle of the outdoor machine itself is to print the design results that were previously in the computer. To drive an outdoor machine requires expertise and understanding in its use and there is a mode of acceleration of the printing process on an outdoor machine whose acceleration of the printing process is not yet known, where the acceleration of the printing process can affect consumer satisfaction. This study aims to 1) Knowing about Digital Print Tools as well as. 2) Knowing the use of Outdoor Digital Printing Machines. 3) Knowing the print speed of the outdoor machine. 4) Knowing the percentage of customer satisfaction. The research method used is the R&D method. By using the R&D method, the results obtained to determine the speed of the outdoor engine on the printhead motor with LOW mode have a speed of 124 m/s, MIDELL mode has a speed of 161 m/s, while HIIGH mode has a speed of 241 m/s. s. The results obtained to determine consumer satisfaction with the speed of the print rate through the time of using the machine using the Guttman scale, namely the overall process time of the outdoor digital printing printing machine on customer satisfaction has a conformity, which is indicated by the percentage of answers "Yes" an average of 75%.

Analysis of Ink Used in Ancient Documents Based on Printing Method

This study evaluates the ink type suitable for document restoration by analyzing ink used in woodblock, metal type-printed, and ancient handwritten documents. Among the commercially available inks, lampblack soot ink (vs. charcoal soot ink) exhibited relatively low hydrogen, oxygen, and nitrogen content and a high spreading ratio to Hanji. Moreover, compared to solid type inks, liquid type inks have a higher absorption ratio into Hanji at the same concentration; thus, drying time after printing is expected to be reduced. Furthermore, different types of ink were used depending on the printing method used in the ancient documents. Therefore, in the future, production efficiency can be improved by classifying ink types based on printing method and using liquid ink rather than solid ink to restore or reproduce histroical documents.

Inkjet ink classification and source prediction based on direct analysis in real-time mass spectrometry (DART-MS) via mass imaging and convolutional neural network (CNN)

This paper presents mass spectrometry imaging (MSI) as an intuitive method of showing the differences between inks, and provides a novel method of ink source prediction based on direct analysis in real-time mass spectrometry (DART-MS) spectral analysis. The ink database comprised 106 types of ink from three brands (Canon, Epson, and HP) with high market share. High-dimensionality reduction methods, such as principal component analysis (PCA), non-negative matrix factorization (NMF), and probabilistic latent semantic analysis (pLSA), were used to reduce the dimensions of the mass spectral data. Characteristics and statistical descriptions of the mass spectra of each ink are given in this paper. Then, MSI was used to visualize the results after PCA, NMF, and pLSA. Finally, a convolutional neural network (CNN) was applied to the data after high-dimensionality reductions, which helped predict the ink source. Results showed efficient and excellent performance of machine-learning analysis in ink source prediction using one pixel in MSI (100% for black, magenta, and yellow inks; 99.6% for cyan ink). In addition, a blind test was used to validate the performance of the CNN model, with results showing that the more pixels used, the more accurate the results. Therefore, we strongly recommend wide-area detection of ink to ensure accurate results.

A flexible tactile sensor based on piezoresistive thin film for 3D force detection.

This paper presents a flexible tactile sensor with a compact structure based on a piezoresistive thin film and an elastomer for detecting three-dimensional (3D) force. The film contains four independent sensing cells, which were made using a type of piezoresistive ink and a specific pectinate conductive circuit pattern based on the flexible substrate to decrease the coupling effect. The elastomer with a spherical surface is bonded to the surface of the film and transfers the force to the sensing array. A model of 3D force detection based on the proposed sensor was established, and a prototype was designed and developed. Static and dynamic experiments were carried out, and the results show that the range of the prototype is 0-50 N in the z-axis and 0-6 N in the x-axis and y-axis, which with good static and dynamic performance, especially a low coupling effect, validates the mechanism of the proposed sensor and indicates that it has good potential application in robotic grasping.

Artificial Intelligence‐Assisted High‐Throughput Screening of Printing Conditions of Hydrogel Architectures for Accelerated Diabetic Wound Healing

AbstractIn 3D (bio)printing, it is critical to optimize the printing conditions to obtain scaffolds with designed structures and good uniformities. Traditional approaches for optimizing the parameters oftentimes rely on the prior knowledge of the operators and tedious optimization experiments, which can be both time‐consuming and labor‐intensive. Moreover, with the rapid increase in the types of biomaterial inks and the geometrical complexities of the scaffolds to be fabricated, such a traditional strategy may prove less effective. To address the challenge, an artificial intelligence‐assisted high‐throughput printing‐condition‐screening system (AI‐HTPCSS) is proposed, which is composed of a programmable pneumatic extrusion (bio)printer and an AI‐assisted image‐analysis algorithm. Based on the AI‐HTPCSS, the printing conditions for obtaining uniformly structured hydrogel architectures are screened in a high‐throughput manner. The results show that the scaffolds printed under the optimized conditions demonstrate satisfying mechanical properties, in vitro biological performances, and efficacy in accelerating the diabetic wound healing in vivo. The unique AI‐HTPCSS is expected to offer an enabling platform technology on streamlining the manufacturing of tissue‐engineering scaffolds through 3D (bio)printing techniques in the future.