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This paper aims to study microwave pad dyeing process for wool fabric. Influences of various dyeing process conditions including galactomannan dosage, urea dosage, sodium bisulphite dosage, pH value, microwave irradiation power, treating time and cold batching time before microwave fixation on K/S values were analysed. The colour yield, fixation and levelness were compared between microwave fixation and cold batching fixation.

Colour yield (K/S values) was calculated using a Datacolor SF650 colour measuring and matching instrument (10° standard observer, CIE D65 light source Measuring; Datacolor, USA) and was used to determine the depth of the shade of dyed wool fabrics. Levelness of dyeing was evaluated also using the Datacolor SF650 colour measuring and matching instrument by measuring average deviation (S), range (P) of the maximum and the minimum for lightness (L), chroma (C) and hue (h), and balanced colour difference (ΔE) at 20 specified uniform locations on the wool fabrics. The colour difference was calculated as per the equation ΔE=(ΔL2+Δa2+Δb2)1/2 as appearing in the Experimental section. Fixation was determined using a Datacolor SF650 colour measuring and matching instrument by measuring ratio the of K/S for wool fabrics that were rinsed, washed, neutralised and then dried, and wool fabrics that were dried after fixation without washing. The pH of the padding solution was evaluated using a PHSJ-4A PH meter (Datacolor, USA). SEM analysis was done on JEOL JSM-5600LV machine (JEOL Ltd, Japan).

This study is based on application of microwave technology in the processing of silk.

It was found in laboratory experiments that uniform dyeing and deeper colour can be achieved throughout the microwave pad dyeing process for wool by using galactomannan. The novel process could reduce the dyeing time and the energy consumption of the traditional cold pad-batch dyeing process for wool fabric.

This paper aims to introduce and illustrate a computational technique capable of determining the geometry and complex permittivity of a supplementary dielectric insert making distributions of microwave-induced dissipated power within the processed material as uniform as possible.

The proposed technique is based on a 3D electromagnetic model of the cavity containing both the processed material and the insert. Optimization problem is formulated for design variables (geometrical and material parameters of the insert) identified from computational tests and an objective function (the relative standard deviation [RSD]) introduced as a metric of the field uniformity. Numerical inversion is performed with the method of sequential quadratic programming.

Functionality of the procedure is illustrated by synthesis of a dielectric insert in an applicator for microwave fixation. Optimization is completed for four design variables (two geometrical parameters, dielectric constant and the loss factor of the insert) with 1,000 points in the database. The best three optimal solutions provide RSD approximately 20 per cent, whereas for the patterns corresponding to all 1,000 non-optimized (randomly chosen) sets of design variables this metric is in the interval from 27 to 136 per cent with the average of 78 per cent.

As microwave thermal processing is intrinsically inhomogeneous and the heating time is not a part of the underlying model, the procedure is able to lead only to a certain degree of closeness to uniformity and is intended for applications with high heating rates. The initial phase of computational identification of design variables and their bounds is therefore very important and may pre-condition the “quality” of the optimal solution. The technique may work more efficiently in combination with advanced optimization techniques dealing with “smart” (rather than random) generation of the data; for the use with more general microwave heating processes characterized by lower heating rates, the technique has to use the metric of non-uniformity involving temperature and heating time.

While the procedure can be used for computer-aided design (CAD) of microwave applicators, a related practical limitation may emerge from the fact that the material with particular complex permittivity (determined in the course of optimization) may not exist. In such cases, the procedure can be rerun for the constant values of material parameters of the available medium mostly close to the optimal ones to tune geometrical parameters of the insert. Special manufacturing techniques capable of producing a material with required complex permittivity also may be a practical option here.

Non-uniformity of microwave heating remains a key challenge in the design of many practical applicators. This paper suggests a concept of a practical CAD and outlines corresponding computational procedure that could be used for designing a range of applied systems with high heating rates.

This study aims to use multi-functional viscose fabric that was facilely developed with with respect to ease and care characteristics, reinforcement effect and antibacterial activity by using novel echo friendly antibacterial finish based on citric acid/sodium hypophosphite and the authors’ previously tailor-made poly meth acrylic acid (MAA)-chitosan graft copolymer via alternative microwave curing approach instead of traditional high-temperature cure one.

Viscose fabric was paddled twice in the cross-linking formulations containing different concentrations of citric acid, poly (MAA)-chitosan graft copolymer and sodium hypophosphite to 90 % wet pick up and dried at 100°C for 3 min in an electric oven. Then, the treated fabrics were placed on the disk spinner of the microwave oven and cured at different power (100–800 Watt) for various durations (60–180 s). The fabric was then water-rinsed and dried at ambient condition before use.

Results revealed that the above echo friendly method for finished viscose fabrics was found to achieve relatively high dry wrinkle recovery angle and maintain the loss in tensile strength within the acceptable range, as well as antibacterial activity against Escherichia coli and Staphylococcus aureus as a gram-negative and gram-positive bacteria, respectively; in addition to durability up to ten washing cycles. Furthermore, scanning electron microscope images, nitrogen content and add on % of the finished fabric confirmed the penetration of grafted chitosan inside the fabric structure. The tentative mechanism for these reactions is advocated.

The novelty addressed here is undertaken with the advantages of using citric acid as a nonformaldehyde, safe and cheap poly carboxylic acid as a crosslinking agent and sodium hypophosphite as a potential catalyst, in addition to the authors’ noncitable multifunctional echo friendly tailor-made poly (MAA)-chitosan graft copolymer for imparting reinforcement and antibacterial characteristics to viscose fabric that uses the pad-dry/cure microwave fixation for progressively persuaded heat within the fabric during curing.

This was done to see the impact of microwave as green and efficient tool with respect to reduction in organic solvents, chemicals and exposer time as well as fixation temperature on the finishing reaction in comparison with traditional pad-dry-cure method.

Poly (MAA)-chitosan graft copolymer as amphoteric biopolymer was expected to impart multifunctional properties to viscose fabrics especially with comparable dry wrinkle recovery angle and minimize the loss in tensile strength in addition to antibacterial properties in comparison with untreated one.

“A Canadian company required information on a process in Switzerland. Since data were too complicated to obtain by mail a vice‐president of the company was assigned to make a trip. The company librarian hearing of this situation accidentally made a search and produced the information from the company's own files.”

To develop a method based on urea/microwave treatment for improving the dyeability of the flax fibre.

The treatment was carried out under a variety of conditions in terms of the power of the microwave, the time of microwave treatment and the use of urea in the treatment solution. The physical chemical properties of the treated flax fibres were characterised using a variety of techniques including scanning electron microscopy (SEM), X‐ray diffractometry, spectrophotometric measurement and tensile measurement.

It was found that the treated flax fibres had significantly improved dyeability. The causes to the improvement of the dyeability of the flax fibre were found to be the increased absorption of dye on the fibre and the increased reaction probability between the dye and the fibre. The procedure for optimum modification appeared to be soaking the flax fabrics in 10 per cent urea solution; treating the fabrics with microwave at 350 W for 2.5 minutes; and treating the fabrics with microwave at 700 W for one minute.

The treatment method developed addressed a problem of great concern in textile coloration, i.e. poor dyeability of flax fibre. The method developed provided a practical and effective solution to such a problem.

The method of treatment of flax fibre, involving soaking in urea and baking in microwave, for the improvement of dyeability was novel. The method could be adapted for use in industrial scale flax dyeing with satisfactory levels of exhaustion and fixation.

The purpose of this paper is to synthesize some novel 2-amino-6,6-dimethyl-9-phenyl-3-(phenyldiazenyl)-6,7-dihydropyrazolo-[5,1-b]quinazolin-8(5H)-one derivatives by multi-component one-pot reaction using a microwave as a new tool for green chemistry.

An equimolor from arylazopyrazole, 5,5-dimethyl-1,3-cyclohexanedione (dimedone) and benzaldehyde derivatives was dissolved in Dimethylformamide (DMF) to be irradiated in a microwave for 15 minutes; after completion of the reaction, as indicated by Thin layer chromatograph (TLC), the reaction mixture was poured into ice water, filtered and then crystallized with an appropriate solvent.

The structure of the synthesized dyes was established and confirmed for the reaction products on the basis of their elemental analysis and spectral data (MS, IR and 1H-NMR). These prepared dyes were used to print polyester and polyamide fabrics using synthetic thickener in the printing paste for the silk screen technique. The synthesized dyes are superior in terms of yield, purity, color strength and fastness properties and will lead to valuable achievements for commercial production.

An efficient method for synthesis of pyrazoloquinazolinone dyes was designed. The novel procedure features short reaction time, moderate yields and simple workup. The authors studied its application in printing polyester and polyamide fabrics.

This paper aims to present an experimental and theoretical study oriented to investigate the potential use of localized microwave-heating (LMH) in 3D-printing and additive-manufacturing (AM) processes.

Following a previous study by the authors, a magnetic confinement technique is developed here as a non-contact support for the incremental solidification by LMH of small metal-powder batches. This approach, which saves the need for a mechanic support in contact with the powder-batch during the microwave heating, may significantly simplify the LMH–AM process.

The powder properties are characterized, and a theoretical LMH model is used to simulate the LMH mechanism dominated here by magnetic eddy currents.

The experimental products are analyzed, and their hardness, porosity and oxidation are evaluated. Practical considerations and further improvements of the non-contact LMH–AM process are discussed.

This paper aims to synthesise coumarine flourescent dyes from a cheap material in a very short time with a very high yield, and by using a clean green chemistry.

Efficient microwave synthesis for some novel iminocoumarins starts from the reaction of p-phenyl-enediamine and ethyl cyanoacetate followed by cyclocondensation with salicylaldehyde derivatives.

The synthesized iminocoumarine compounds were characterized by spectroscopic methods. Absorption and fluorescence spectra of the compounds were also recorded. All compounds were fluorescent in 1,4-dioxane solution, they all emitted blue light (440-460 nm). The printing properties were studied, and their applications on printing polyester and polyamide fabrics were studied by silk screen printing.

The authors designed efficient microwavel synthesis for some novel iminocoumarine derivatives; The novel procedure features short-reaction time, moderate yields and simple workup; All compounds were fluorescent in 1,4-dioxane solution, and they all emitted blue light; The authors studied their application in printing polyester and polyamide fabrics.

The purpose of this study is to successfully implement microwave irradiation for the rapid synthesis of novel fluorescent dyes. The prepared dyes are then applied for printing of polyester and polyamide by silk screen printing process.

A series of new N′-(methylene)-2-imino-2H-chromene-3-carbohydrazide derivatives 3a–r were synthesised in excellent yield and high atom economy by the Knoevenagel condensation of salicylaldehyde derivatives 1 and cyano-N′-methyleneaceto-hydrazide derivatives 2 in the presence of piperidine catalyst. The optical properties of the synthesised compounds were recorded; all of the compounds were found to be fluorescent in 1, 4-dioxane solution; they all emitted blue light (440-460 nm). This work shows that the optical properties strongly depend on the nature of the substituent, and indicate which type of substituent is favourable for a given application. It confirms that iminocoumarin derivatives could lead to a new generation of fluorescent probes, prone to easy modification of their chemical structure. These synthesised dyes are used to print polyester and polyamide fabrics using synthetic thickener in the printing paste for silk screen technique.

The structures of synthesised dyes were established and confirmed for the reaction products on the basis of their elemental analysis and spectral data (MS, IR and 1H-NMR). The suitability of the prepared dyestuffs for traditional printing on polyester and polyamide fabrics has been investigated. The prints obtained using the synthesised dyes were found to possess high colour strength and excellent overall fastness properties but relatively low light fastness.

The synthesised fluorescent dyes were prepared by a simple reaction process in microwave. The optical properties for obtained dyes show include the fact that it will have various important applications. In addition, they were used for printing synthetic fabrics and were found to have good results.

The new fluorescent dyes’ system has excellent printing properties. Also they are superior in terms of yield, purity, colour strength and fastness properties which may lend them valuable commercial production.

The result of this work aimed to define the scope and limitation of the procedures for the synthesis of novel iminocoumarin dyes via a simple and economic way.

This study aims to represent a successful simple method for the synthesis of some novel dyes based on thiazole derivatives and their applications in textile printing.

2-(benzo[d]thiazol-2-ylmethyl)thiazol-4(5H)-one compound is prepared by convention heating and microwave technique then used as a coupling agent, which reacts with different diazonium Salt to form diazo dyes.

The synthesized diazo dyes are confirmed via spectral data (IR,1H-NMR, 13C-NMR and Mass spectra). The dyes are used to print polyester fabric. The obtained results clarified that the prints have good color strength, brilliant color and highly durable antibacterial activity.

The authors designed efficient synthesis for some novel thiazolone dyes. The novel procedure features short-reaction time, very good yields and a simple workup. The authors studied the antibacterial activity and their application in printing polyester fabrics.