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This paper presents an eco-friendly method for wool fabrics to improve printing characteristics without thermal fixation via a UV/ozone pre-treatment. Such treatment causes surface morphological changes and oxidizes wool fabric surfaces. In this study, the changes in surface composition and chemistry induced by this treatment were followed by measuring changes in electron spin resonance (ESR) intensity values and mechanical properties, including tensile strength, elongation percentage and air permeability of the treated wool fabric samples. The pre-treated fabrics were printed and their colour strength (K/S) values with all colour parameters were measured. Fastness properties, such as colour fastness to light, washing and perspiration, were evaluated. Printability of the pre-treated fabrics was compared with that of the printed fabrics by conventional methods. The results showed that the UV/ozone treatment improved printing fixation of dye without energy consumption which is required by conventional methods. The UV/ozone treatment imparts highly printed shades of woolen fabrics at reduced energy with excellent fastness properties of the pre-treated printed fabrics.

This paper presents results on adding silane coupling agents to the underfill encapsulant to enhance the rheology and wetting of the underfill. These results include rheology measurements, contact angle measurements, and in situ flows using a simulated test chip on an FR4 with solder mask substrate. Three properties of the underfill encapsulant that can affect the mechanical reliability of the die and substrate assembly are: CTE; elastic modulus; and adhesion to the die and substrate surfaces. The approach taken in this paper is to add silane coupling agents with different chemistries to the underfill encapsulant to provide interfacial coupling of the underfill material to different die and substrate materials. This paper presents results on the enhancement of the adhesion of underfill encapsulant to silicon (Si), silicon nitride (SiN) die passivation, benzocyclobutene (BCB) die passivation, and solder mask surfaces. The adhesion strength was measured by die shear testing.

Recently, much attention has been focused on using physical treatments for improving functional properties of polymeric fabrics since they have several useful advantages, such as non toxicity, soil release, improving physical properties and chemical reactivity of fabrics, avoiding environmental pollution resulting from chemical modification, etc. Hence, this article discusses the feasiblity and characterization of using UV/ozone treatments as a source of surface modification on the surface and bulk characteristics of various polymeric fabrics. Thus, pure cotton, pure polyester, and blend (cotton/polyester) fabrics are treated with UV/ozone for different periods of time (1,3,5,10,15, 20 and 60 minutes). The treated samples are examined and evaluated through various measurements involving the Fourier transform infrared spectra (FTIR) that provides evidence for the changes in the peak intensity values of different functional groups characterizing each fabric ,whiteness and yellowness indices, tensile strength, percentage elongation, and Young's modulus values, which are inversely related to the elacticity of the fabric. Moreover, the efficiency of this treatment process is tested by evaluating the dyeing characteristics by using two different dye classes which involve measuring dye up-take (K/S) values and light fastness assessments.

Ethylene diamine tetra‐acetic acid (EDTA) and other chelates are widely employed in the electroless copper plating solutions and related chemistries used in printed circuit board (PCB) manufacturing. EDTA in particular, imparts many benefits to these processes but it is also becoming increasingly undesirable from an effluent treatment and environmental perspective. Consequently, there is a need to remove EDTA and similar compounds from effluent produced during the PCB manufacturing process. In this paper, the effectiveness of hydroxyl radicals, generated by a UV/ozone based enhanced oxidation process, in destroying relatively low levels of EDTA and other chelates has been evaluated. The influence of temperature, operating pH and chelate concentration has been investigated. Initial results indicate that a combined UV/ozone based process provides a useful and effective method for conveniently destroying EDTA, its hydroxy ethyl analogue and ethanolamine in aqueous solution.

Ethylenediaminetetraacetic acid and other organic chelates are widely employed in electroless plating processes used by the printed circuit board and metal finishing industries. These chelating agents can pose problems with downstream waste water treatment, and metals and water recycling processes, due to their ability to complex heavy metal ions and their low biodegradabilities. Conventional treatment methods, such as carbon adsorption, air stripping and reverse osmosis can create secondary waste problems and are normally applied as “end of pipe” treatments. The development of new technology to address these problems would be welcomed. The ROCWAT project, funded by the EC under the “CRAFT” programme, detailed in this paper was undertaken to develop and deliver innovative techniques for the in situ destruction of chelates and other organics found in manufacturing process chemistries and effluent streams.

The aim of this study is to determine the effect of argon plasma surface modification on tribological properties of conventional ultra-high molecular weight polyethylene (UHMWPE) and vitamin E-blended UHMWPE. In previous studies, some researchers conducted a study on argon plasma surface modification of UHMWPE, but there is no study about argon plasma surface modification of VE-UHMWPE. So another objective of this paper is to compare the results for both the material groups.

UHMWPE and vitamin E-blended UHMWPE sample surfaces were modified by microwave-induced argon plasma to increase tribological properties of the materials. The modified surfaces were evaluated in terms of wettability and wear behavior. Wettability of the surfaces was determined by contact angle measurements. Wear behavior was examined by ball-on-disc wear tests under lubrication with 25 per cent bovine serum.

Argon plasma surface modification enhanced the wear resistance and surface wettability properties of conventional UHMWPE and VE-UHMWPE. Wear factor of argon plasma-treated samples reduced, but for VE-UHMWPE samples, this reduction was not as high as the conventional UHMWPE’s wear factor.

In previous studies, some researchers have studied on argon plasma surface modification of UHMWPE, but there is no study about argon plasma surface modification of VE-UHMWPE.

The purpose of this paper is to present a novel manufacturing process that aims to pattern metal tracks onto polyimide at atmospheric pressure and ambient environment. The process can be scaled up for industrial applications.

From a thorough literature survey, different approaches were carried out for processing polyimide. Following a design of experiments for the processing and various characterisation techniques, a micro‐coil was manufactured as a test demonstrator.

The characteristics of some main formaldehyde‐based electroless copper baths were compared. The quality of the sidewalls was characterised and the performance of the process was assessed.

This paper demonstrates a high‐value manufacturing technique that is mass manufacturable, low cost and suitable for use on 3D surfaces. Criteria required for the development of a direct‐writing process have been described. The issues surrounding electroless plating on polyimide have been explained.

Purpose This study aims to apply the impedance spectroscopy (IS) for analyzing the electrical behavior and extracting the equivalent circuit of single-layer flexible organic light-emitting diodes (OLEDs) with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) anode.

The preliminary ultraviolet (UV) treatment of the flexible substrate of polyethylene terephthalate (PET) influenced the conductivity of PEDOT:PSS anodes.

The IS showed that the OLED with UV-treated PET/PEDOT:PSS anodes had lower values of the contact resistance and higher value of the interface capacitance.

The obtained data were used for modeling of flexible OLEDs with polymeric anodes and calculation of important display parameters such as pixel refresh ratio, signal delays and energy losses due to contact resistances. These parameters were compared for PEDOT:PSS anodes deposited on PET treated and non-treated by UV.

Despite the increasing popularity of natural dyeing of textiles, the low substantivity between the fibers and the natural dyes is a problem. Several methods have been used to overcome this problem. In this study, wool fibers were pretreated with oxygen plasma under different conditions and dyed with the extract of grape leaves. The purpose of this study is to investigate the effects of plasma treatment parameters on the color strength of the dyed samples using artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) and evaluate the ability of these methods for predicting the color strength.

Woolen yarns were modified under different conditions of oxygen plasma treatment. Oxygen flow rate, power and time were considered as the treatment variable factors. Plasma-treated samples were dyed under constant conditions with the extract of grape leaves as a natural dye. ANN and ANFIS were applied to model and analyze the effect of plasma treatment parameters on the color strength of the dyed samples.

The results showed that increasing all the plasma treatment process variables, including oxygen flow rate, power and time increased the color strength of the dyed samples. The results showed that the developed ANN and ANFIS could accurately predict the experimental data with correlation coefficients of 0.986 and 0.997, respectively. According to the obtained correlation coefficients, ANFIS had a higher accuracy in prediction of the results of this study compared with the ANN and RSM models (correlation coefficient = 0.902, from our previous study).

This study uses ANN and ANFIS for predicting color strength of naturally dyed textiles for the first time. The use of computational intelligence for the optimization and prediction of the effects plasma treatment for the improvement of natural dyeing of wool is another novelty of this study.

Everyone is extremely concerned about environmental protection and health safety due to the rise in living standards. Plant-derived natural dyes have garnered much industrial attention in food, pharmaceutical, textile, cosmetics, etc. owing to their health and environmental benefits. The present study aims to focus on the elimination of the use of synthetic dyes and provides brief information about natural dyes, their sources, extraction procedures with characterization and various advantages and disadvantages.

In producing natural colors, extraction and purification are essential steps. Various conventional methods used till date have a low yield, as these consume a lot of solvent volume, time, labor and energy or may destroy the coloring behavior of the actual molecules. The establishment of proper characterization and certification protocols for natural dyes would improve the yielding of natural dyes and benefit both producers and users.

However, scientists have found modern extraction methods to obtain maximum color yield. They are also modifying the fabric surface to appraise its uptake behavior of color. Various extraction techniques such as solvent, aqueous, enzymatic and fermentation and extraction with microwave or ultrasonic energy, supercritical fluid extraction and alkaline or acid extraction are currently available for these natural dyes and are summarized in the present review article.

If natural dye availability can be increased by the different extraction measures and the cost of purified dyes can be brought down with a proper certification mechanism, there is a wide scope for the adoption of these dyes by small-scale dyeing units.