Blue Ink Research Articles

Preparation and characterization of Phthalocyanine Blue encapsulated with silane coupling agent for blue light curable inkjet printing of textiles

A novel reactive organic pigment complex was prepared by 3-(Trimethoxysilyl) propyl methacrylate encapsulated on the surface of the organic pigment. The preparation conditions of the reactive organic pigment complex were optimized and the properties were characterized by FT-IR, DLS and UV–vis. The reactive organic pigment complex was used in blue-light curable pigment inks. The results showed that the photo-polymerization performance of the novel blue light curable pigment ink system was markedly increased in comparison with conventional pigment-based ink systems. The physical shielding effect of pigment particles on photo-polymerization performance can be reduced by increasing the photoinitiator concentration and irradiation intensities. The colorfastness to crocking of printed fabric was remarkably improved. However, the particle size of reactive organic pigment complex was slightly increased.

A novel combined approach of diffuse reflectance UV–Vis-NIR spectroscopy and multivariate analysis for non-destructive examination of blue ballpoint pen inks in forensic application

The present research is focused on the analysis of writing inks using destructive UV–Vis spectroscopy (dissolution of ink by the solvent) and non-destructive diffuse reflectance UV–Vis-NIR spectroscopy along with Chemometrics. Fifty seven samples of blue ballpoint pen inks were analyzed under optimum conditions to determine the differences in spectral features of inks among same and different manufacturers. Normalization was performed on the spectroscopic data before chemometric analysis. Principal Component Analysis (PCA) and K-mean cluster analysis were used on the data to ascertain whether the blue ballpoint pen inks could be differentiated by their UV–Vis/UV–Vis NIR spectra.The discriminating power is calculated by qualitative analysis by the visual comparison of the spectra (absorbance peaks), produced by the destructive and non-destructive methods. In the latter two methods, the pairwise comparison is made by incorporating the clustering method. It is found that chemometric method provides better discriminating power (98.72% and 99.46%, in destructive and non-destructive, respectively) in comparison to the qualitative analysis (69.67%).

A multi-technique approach to the chemical characterization of colored inks in contemporary art: The materials of Lucio Fontana

Abstract The present study aims to the characterization of the materials at the disposal of the artist Lucio Fontana. In particular, several analytical techniques were employed to determine the chemical composition of thirteen inks found in Fontana's studio in Milan. Synthetic dyes responsible for the different shades of the inks were identified mainly by means of conventional Raman and surface-enhanced Raman spectroscopy as well as by high-performance liquid chromatography. Indeed, rhodamine-based dyes, often in mixture with yellow colorants such as metanil and acridine yellow, or monoazo dyes were detected in red and ochre inks. Triarylmethane and phthalocyanine molecules were identified in green and blue inks, while the azine compound nigrosine was found in a black ink. The presence of binders, such as gum Arabic and shellac, was instead detected in ink formulations by means of Fourier transform infrared spectroscopy. Moreover, an evaluation of the possibility to perform non-invasive analyses for the characterization of such materials was carried out by means of micro-Raman and reflection FTIR spectroscopies, resulting successful only for selected dyes. On the contrary, non-destructive analyses by reflectance spectroscopy and spectrofluorimetry allowed to start building a spectral database of such materials, potentially useful also for field investigations. More generally, the entire study allowed to obtain important information for future analytical work both on Fontana's paintings and on colored inks used in 20th century art.

Vascular territories of the medial upper arm-an anatomic study of the vascular basis for individualized flap design.

Fasciocutaneous flaps supplied by discrete perforator arteries can be raised in numerous parts of the human body and are routinely used in plastic surgery. The aim of this anatomical investigation was to provide a description of the vascular supply of the medial upper arm, to localize and measure the perforator arteries and to define potential perforator flap dimensions in pendency of individual anatomical conditions. A total of 20 upper limbs from 11 fresh cadavers were examined. The brachial arteries were exposed and the medial perforator arteries selectively injected with methylene blue and india ink in an alternating sequence. The size of the angiosomes, the diameter and length of the perforators' pedicles and distances between the arteries and the medial epicondyle and apex of the axilla respectively were measured. On average, 4.55 ± 1.47 perforating arteries arose from the brachial artery and it's medial off branching arteries. Their mean diameter was 0.68 ± 0.27 mm and their pedicles had an average length of 3.62 ± 1.61 cm measured from suprafascial until arborisation. In 80% the first proximal perforator was present in an area of 4 cm radius at centre coordinates of (20/2). A constant distal perforator was found within a circle of 3 cm radius, of which the centre had the coordinates (8/1). The average size of the angiosomes was 121.1 ± 58.5 cm2 . Direct branches of the brachial artery feed circular shaped vascular territories, whereas superior ulnar collateral arteries (SUCAs) feed oblong shaped territories. This anatomical study provides valuable data of the medial arm flap in order to be applied clinically. © 2016 Wiley Periodicals, Inc.

Rapid fabrication of a four-layer PMMA-based microfluidic chip using CO2-laser micromachining and thermal bonding

A smart design method to transform the original two-layer microfluidic chip into a four-layer 3D microfluidic chip is proposed. A novel fabrication method is established to rapidly and effectively produce a four-layer microfluidic chip device made entirely from polymethylmethacrylate (PMMA). Firstly, the CO2-laser cuts the PMMA sheets by melting and blowing away vaporized material from the parent material to obtain high-quality channels of the microfluidic chip. An orthogonal experimental method is used to study its processing stability. In addition, a simple, rapid thermal bonding technique is successfully applied in fabricating the four-layer microfluidic chip, which has a bond strength of 1.3 MPa. A wooden pole is used to improve the accuracy of the alignment. Finally, a mixing experiment with blue ink and water is carried out, which proves that this smart design method and rapid manufacturing technology are successful.

Preparation and Properties of Blue Edible Inkjet Ink Based on Chitosan Oligochitosan

Different formulations of blue edible inkjet inks were prepared in this study using chitosan oligochitosan as a binder. The properties of different formulations of the ink were analysed by measuring conductivity, surface tension, viscosity, and antimicrobial properties. Chromaticity and density experiments were also conducted on the blue inkjet inks. Results show that the quality of the printed matter was improved considerably, including enhanced resolution, antimicrobial resistance, and reduced graphic burrs, after the addition of chitosan oligosaccharide.

Copper-based superhydrophobic materials with long-term durability, stability, regenerability, and self-cleaning property

This work reports a simple and environment-friendly method for fabricating copper-based superhydrophobic materials by oxidation, lauryl mercaptan modification, and compression moulding. The as-prepared copper blocks are characterized by XRD, FT-IR, SEM, EDS, and contact angle measurements. Results show that the block surfaces show cauliflower-like structure, while long lauryl mercaptan chains are self-assembled onto surfaces successfully. Consequently, the superhydrophobic copper blocks with a contact angle and a sliding angle of 155.2° and below 5° are obtained. Moreover, the strong repellency of these copper-based materials have universality for milk, blue ink, methyl orange solution, methylene blue solution, and so on. The materials as well as the superhydrophobicity remain even in adverse conditions. They could be placed in the air for ten months, soaked in water for half a month, or over a wide pH range (i.e, pH=6–14) without any notable changes. More importantly, the superhydrophobicity can be regenerated once the superhydrophobic surfaces are destroyed by abrasion, scratching, or fouling. Meanwhile, the superhydrophobic copper blocks have excellent self-cleaning property. The contaminating particles on the copper blocks can be easily taken away by rolling water droplets. The results show that these copper-based superhydrophobic materials have long-term durability and stability, and may see practical application of the superhydrophobic materials.

Nondestructive classification and identification of ballpoint pen inks by Raman spectroscopy for forensic document examinations

As a non-destructive analytical method, Raman spectroscopy often provides insufficient information to identify or differentiate the ink used for the preparation of a questioned document. In this study, blue and black ballpoint pen inks deposited on paper substrate were examined in situ by conventional Raman spectroscopy. Inks were successfully classified based on the total number of prominent bands in Raman spectra. It was found that more than 90% of the samples of the same type and color could be differentiated visually using only Raman spectra, i.e. 94 and 95% for blue and black inks, respectively. As a result of this study, a flow chart has been constructed for blue and black ballpoint pen inks allowing their systematic identification. Raman spectroscopy proved to be a fast and precise technique for forensic ink analysis.

Picosecond lasers for tattoo removal: a systematic review.

Given that the pigment particles in tattoos have a relaxation time of <10ns, picosecond lasers would be expected to be more effective than nanosecond lasers in tattoo removal. To systematically review the evidence regarding the effectiveness and safety of picosecond lasers for tattoo removal, Pubmed, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov, and reference lists were searched for relevant trials. The primary outcome was >70% clearance of tattoo pigment. Secondary outcomes were 90-100% clearance of tattoo pigment, number of laser sessions required, and adverse effects. Eight trials were included, six with human participants (160 participants) and 2 with animal models. Seven of the eight trials explored the usage of either 755, 758, 795, 1064, or 1064/532-nm picosecond lasers for black and blue ink tattoos. In the human trials, 69-100% of tattoos showed over 70% clearance of pigment after 1-10 laser treatments. Reported side effects included pain, hyperpigmentation and hypopigmentation, blister formation and transient erythema, edema, and pinpoint bleeding. Included articles varied in type of laser investigated, mostly non-comparative studies and with a medium to high risk of bias. There is sparse evidence that picosecond lasers are more effective than their nanosecond counterparts for mainly black and blue ink tattoo removal, with minor side effects.

Nondestructive identification of blue pen inks for documentoscopy purpose using iPhone and digital image analysis including an approach for interval confidence estimation in PLS-DA models validation

Documentoscopy is a field of forensic science that studies documents related to crime investigations. In this sense, the evaluation of pen inks used to produce these documents can help in the counterfeits identification, and the analysis of inks in paper is an important area in documentoscopy. In order to develop a methodology that allows the nondestructive accurate discrimination of pen inks types (gel, rollerball, felt tip and ballpoint pens) partial least squares for discriminant analysis (PLS-DA) was applied for the digital images obtained from an iPhone. The proposed method was tested for discrimination between 42 blue pen inks of different types and brands and validated by independent validation (or test) samples. The interval confidences estimation were considered in the validation step. Evaluations about the effect of paper characteristics and influence of the utilization of a smartphone from another brand were described. The digital images coupled with PLS-DA model can be considered robust for felt-tip pen type, since the model for this pen type did not suffer influence of the paper grammage and smartphone brand. Therefore, the proposed methodology may be considered a relevant contribution to the forensic analysis of questioned documents, since it provides a simple, fast, nondestructive and efficient way to directly analyze blue pen inks.

Pt@AuNPs integrated quantitative capillary-based biosensors for point-of-care testing application

Current diagnostic technologies primarily rely on bulky and costly analytical instruments. Therefore, cost-effective and portable diagnosis tools that can be used for point-of-care tests (POCT) are highly desirable. In this study, we report a cost-effective, portable capillary-based biosensor for quantitative detection of biomarkers by the naked eye. This capillary-based biosensor was tested by measuring the distance of blue ink movement, which was directly correlated with the oxygen (O2) produced by efficient core-shell Pt@Au nanoparticles (Pt@AuNPs) catalysts decomposed hydrogen peroxide (H2O2). By linking the Pt@AuNPs with antibodies, capillary-based biosensor sandwich immunoassays were constructed. The concentrations of the target proteins were positively correlated with the distances of ink movement. To demonstrate their performance, the biosensors were used to detect the cancer biomarker sprostate-specific antigen (PSA) and carcinoembryonic antigen (CEA). The linear detection range (LDR) of the capillary-based biosensor for detecting PSA was from 0.02 to 2.5ng/mL, and the limit of detection (LOD) was 0.017ng/mL. LDR of the biosensor for detecting CEA was from 0.063 to 16ng/mL, and the LOD was 0.044ng/mL. For detection of PSA and CEA in clinical serum samples, the detection results of the capillary-based biosensor were well correlate with the results from of chemiluminescence immunoassays (CLIAs). Thus, the capillary-based biosensor may potentially be a useful strategy for point-of-care testing, in addition to being portable and cost effective.

The investigation of dye aging dynamics in writing inks using Raman spectroscopy

The durability against light and aging dynamics of heteroatomic aromatic dyes and pigments containing nitrogen atoms used in writing inks was studied using Raman spectroscopy. The mechanisms of their thermal and photo-decomposition were proposed and the rates of these processes were determined. According to Raman spectroscopy, it was found that depending on the presence of one or another colorant, there are three main types (Type A, Type B and Type C) of blue dye inks used in ballpoint, gel and capillary pens which were studied in this work. Each type is characterized by a certain set of signals in Raman spectra. Time dependencies of Raman signal intensities for each type revealed the dynamics of the processes occurred with colorants included in the studied inks from the moment when they were printed on paper. Thus, the results obtained in this study can be used for the age estimation of the paper documents up to 15 years.

How Much Can a Forensic Laboratory Do to Discriminate Questioned Ink Entries?

Questioned document examiners are frequently required to determine whether the questioned ink entries on a document are written with the same ink, either for forged document identification or relative ink dating. How many methods are sufficient to discriminate potentially different inks? In this paper, 18 blue ballpoint inks were first nondestructively examined with a video spectral comparator. The ink entries were subsequently extracted with organic solvents for analysis of the volatile solvents and dyes by GC/MS, TLC, and LC-MS/MS. The 18 ink samples were divided into 10, 9, 12, and 14 categories by these four methods, respectively. With the combined results, there were only two inks that remained indistinguishable, but they were further differentiated by microscopy. Therefore, to achieve effective discrimination of ballpoint ink entries, the authors suggest that a complete examination should include an analysis of their optical features, volatile solvents, and dyes as well as the ink quality.

Numerical and experimental investigation on micromixers with serpentine microchannels

This paper aims at study and analysis on species mixing performance of micromixers with serpentine microchannels by numerical simulation and experiment in depth. Mixing experiments with blue ink and yellow ink were implemented for six micromixers, and three better structures (square-wave, multi-wave and zigzag) were picked for further simulation research. Lots of productive numerical analysis were carried out for studying the mixing performance for Reynolds number (Re) values in the range from 0.1 to 100. The mixing efficiency decreases while Re varies from 0.1 to 1, and increases while Re varies from 1 to 100. At the Re of 0.1 and 100, the mixing performance of three structures is similar. Vortices, transversal flows and chaotic advection were produced with the increase of Re. Compared with the multi-wave micromixer and the zigzag micromixer, the square-wave micromixer is more efficient on mixing duo to its more sharp turns and longer path of the flow with Re being between 0.1 and 100. The results also show that the square-wave micromixer has higher pressure drops than the other two because of more sharp turns. Each square-wave unit enhances mixing obviously with the increase of Re and at a certain Re the former unit has a stronger effect on mixing than the latter. When Re is more than 100, the mixing efficiency can reach above 95% with a moderate pressure drop less than 50kPa. Both experiment and simulation results demonstrated that the square-wave serpentine micromixer is flexible, effective, easily fabricated and integrated to a microfluidic system.

Phenyl-end-capped-thiophene (P-T type) based ICT fluorescent probe (D–π–A) for detection of Hg2+ and Cu2+ ions: Live cell imaging and logic operation at molecular level

Abstract An intramolecular charge transfer (ICT) based fluorescence turn-on ratiometric probe BTIM ( D – π – A type) has been designed and synthesized by bridging imidazole (donor, D ) and benzothiazole (acceptor, A ) moieties through a thiophene ring. The photophysical behavior of probe and its affinity toward metal ions has been investigated in HEPES buffer, protein medium and live cells. The probe upon interaction with different cations has shown high sensitivity and selectively for Hg 2+ and Cu 2+ ions through fluorescence “turn- On and turn -Off ” response respectively along with naked-eye sensitive color changes. The significant change in photophysical behavior of the probe is attributable to restricted ICT upon complexation between probe and metal ions in a 1:1 stoichiometry. The mechanism of interaction has been established by 1 H NMR, FT-IR, ESI-M Sand DFT calculation methods. The probe has shown excellent cell permeability and successfully detected Hg 2+ and Cu 2+ ions in Dalton’s Lymphoma (DL) cells, in protein medium (BSA), in real water samples and on test paper strips. Moreover, the optical behavior of probe has been explored as a Coding-Decoding Fluorescent Blue Security Ink on silica gel surface and in construction of crossword puzzle with specific security code ‘HCO’.

A Chronic Rash

Allergic reactions have infrequently been reported to metals found in tattoos (e.g., chromium, mercury). We report inflammation in a blue ink tattoo, associated with a positive patch test reaction to cobalt chloride, likely indicating primary sensitization to cobalt.

Detection and identification of dyes in blue writing inks by LC-DAD-orbitrap MS

In the field of forensic questioned document examination, to identify dyes detected in inks not only provides a solid foundation for ink discrimination in forged contents identification, but also facilitates the investigation of ink origin or the study regarding ink dating. To detect and identify potential acid and basic dyes in blue writing inks, a liquid chromatography-diode array detection-Orbitrap mass spectrometry (LC-DAD-Orbitrap MS) method was established. Three sulfonic acid dyes (Acid blue 1, Acid blue 9 and Acid red 52) and six triphenylmethane basic dyes (Ethyl violet, Crystal violet, Methyl violet 2B, Basic blue 7, Victoria blue B and Victoria blue R) were employed as reference dyes for method development. Determination of the nine dyes was validated to evaluate the instrument performance, and it turned out to be sensitive and stable enough for quantification. The method was then applied in the screening analysis of ten blue roller ball pen inks and twenty blue ballpoint pen inks. As a result, including TPR (a de-methylated product of Crystal violet), ten known dyes and four unknown dyes were detected in the inks. The latter were further identified as a de-methylated product of Victoria blue B, Acid blue 104, Acid violet 49 and Acid blue 90, through analyzing their characteristic precursor and product ions acquired by Orbitrap MS with good mass accuracy. The results showed that the established method is capable of detecting and identifying potential dyes in blue writing inks.

Investigation of the chemical origin and evidential value of differences in the SERS spectra of blue gel inks.

Highly swellable polymer films doped with Ag nanoparticle aggregates (poly-SERS films) have been used to record very high signal : noise ratio, reproducible surface-enhanced (resonance) Raman (SER(R)S) spectra of in situ dried ink lines and their constituent dyes using both 633 and 785 nm excitation. These allowed the chemical origins of differences in the SERRS spectra of different inks to be determined. Initial investigation of pure samples of the 10 most common blue dyes showed that the dyes which had very similar chemical structures such as Patent Blue V and Patent Blue VF (which differ only by a single OH group) gave SERRS spectra in which the only indications that the dye structure had been changed were small differences in peak positions or relative intensities of the bands. SERRS studies of 13 gel pen inks were consistent with this observation. In some cases inks from different types of pens could be distinguished even though they were dominated by a single dye such as Victoria Blue B (Zebra Surari) or Victoria Blue BO (Pilot Acroball) because their predominant dye did not appear in other inks. Conversely, identical spectra were also recorded from different types of pens (Pilot G7, Zebra Z-grip) because they all had the same dominant Brilliant Blue G dye. Finally, some of the inks contained mixtures of dyes which could be separated by TLC and removed from the plate before being analysed with the same poly-SERS films. For example, the Pentel EnerGel ink pen was found to give TLC spots corresponding to Erioglaucine and Brilliant Blue G. Overall, this study has shown that the spectral differences between different inks which are based on chemically similar, but nonetheless distinct dyes, are extremely small, so very close matches between SERRS spectra are required for confident identification. Poly-SERS substrates can routinely provide the very stringent reproducibility and sensitivity levels required. This, coupled with the awareness of the reasons underlying the observed differences between similarly coloured inks allows a more confident assessment of the evidential value of inks SERS and should underpin adoption of this approach as a routine method for the forensic examination of inks.

Forensic Discrimination Potential of Video Spectral Comparator and Micro Spectrophotometer in Analyzing Question Document and Fraud Cases in India

The aim of the study was to evaluate the discriminating power of non-destructive methods, including optical methods likes the Video spectral comparator method (VSC) and Micro spectrophotometer (MSP) used to differentiate ballpoint pen ink which is commonly used in question document and fraud cases in India. Documents have been investigated to determine the feasibility of utilizing the Video spectral comparator method (VSC) and Micro spectrophotometer (MSP) for the differentiation and comparison of inks on paper. The work focused on how to develop the most effective procedure to ensure quality, when Micro spectrophotometer is used to differentiate writing materials by characteristics color scan of each ink. Six different commercially available blue ballpoint pen inks produced from most popular pens in Indian Market which were used as research material. We have studied most selling pens in Indian market (Reynolds, Parker, and Lexis 2 types, Cello griper and local made pen) for overwriting, alternation and modification of ballpoint pen ink on documents. These pens are generally used on questioned document in forensic discrimination cases and these questioned documents cases received by forensic science laboratories regularly. In forensic discrimination cases generally initial writing is overwritten by using other ink and to identify which ink was used to overwrite is challenging task in field of forensic science. The present study highlighted that the Video Spectral Comparator method (VSC) and Micro spectrophotometer (MSP) can be used routinely in such types of document cases and it has demonstrated to be an excellent analytical method for the forensic analysis of inks on a questioned document.

The Determination of Signs of Accelerated Ageing of Records made with Ballpoint Pen Inks by Using Chromatography Methods

A study of four different ballpoint pen inks was carried out using methods of HPLC and solid-phase micro extraction and gas chromatography mass spectrometry. Inks of different ballpoint pen manufacturers-two blue ones and two purple ones were chosen for the research. Naturally aged ink samples on paper were stored under various conditions, and the comparative samples were exposed to aggressive influence of light, temperature and ozone. During the study of artificially and naturally aged samples differences in chemical composition of ink were identified-possible signs of accelerated ageing were detected in records and signatures that were made with blue and purple ballpoint pen inks.