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Dyeing process is usually to blame negatively for deteriorating the environment. Eco-friendly silk fibers are able to exercising their commercial values well followed by eco-friendly processing. One of the supporting examples is the process of changing the colors of silk fabrics. This would include the dyeing process used to change the colors of silk fabric. The intention of the study is to reach the goal of creating an eco-friendly finishing process using a local natural plant-based indigo dyeing process that would complement an eco-friendly degumming process. Currently, most dye houses use sodium hydrosulfite (Na₂S₂O₄) and alkali (NaOH) as the substances for providing hydrogen as a reducing agent. Since the sodium hydroxide by-products are acidic, they may damage equipment in the dye houses, generate air pollution in working environment. The other problems associated with the use of sodium hydrosulfite are the cost and instability with low storage.

This paper is based on continuing improvements to the commercialization of the raw materials via the innovative degumming process elaborated in the author’s previous study: “Degumming of Silk Fibers by CO₂ Supercritical Fluid.” The initial study has already proved that it was possible to remove sericin from raw silk fiber by using an organic acid pretreatment and CO₂ supercritical fluid over the heavy processes the industry currently deploys. The sericin removed from this innovative and eco-friendly processing of silk fiber will be remained in a clean state, not in the form of waste via the existing technologies in use. Clean sericin, rich in silk protein with high market values, can be a potentially perfect substitute of collagen the medical and cosmetic industries widely use. The continued research is focused on the other by-product coming out from this eco-friendly degumming process the silk fibers post degumming. Dyeing process is usually to blame negatively for deteriorating the environment. Eco-friendly silk fibers are able to exercising their commercial values well followed by eco-friendly processing. One of the supporting examples is the process of changing the colors of silk fabrics. This would include the dyeing process used to change the colors of silk fabric. The intention of the study is to reach the goal of creating an eco-friendly finishing process using a local natural plant-based indigo dyeing process that would complement an eco-friendly degumming process.

Degumming is an important stage in the silk manufacturing. Due to removing sericin from silk fibers, when subjected the degumming process, these silk fibers acquire the properties, which are of high consumer and commercial values, those include gloss, perfect color, soft handle and texture, elegant drape. Another purpose for the silk fabric degumming is preparing for the next step in processing, such as dyeing or printing. The author has developed a new approach to the degumming process exploiting a supercritical fluid carbon dioxide and found it as a good alternative to the conventional methods that are currently used in industry. Silk fabrics treated by the scCO₂ degumming process are characterized by improved dyeing ability or color strength, while this process does not adversely affect the environment. The implications or potential applications of the findings: as it is clearly seen from Table 1, the effectiveness of the degumming process can be improved by at least 38% applying scCO₂. Moreover, implementation of the scCO₂ silk degumming process into the textile industry may help manufactures to consume less water and energy resources (Elmaaty and Abd El-Aziz, 2017), as well as to obtain pure sericin as a valuable end-product that can be used in the medical and cosmetic industries.

The innovation and novel aspects of research: degumming is an important stage in the silk manufacturing. Due to removing sericin from silk fibers, when subjected the degumming process, these silk fibers acquire the properties, which are of high consumer and commercial values, those include gloss, perfect color, soft handle and texture, elegant drape. Another purpose for the silk fabric degumming is preparing for the next step in processing, such as dyeing or printing. The author has developed a new approach to the degumming process exploiting a supercritical fluid carbon dioxide and found it as a good alternative to the conventional methods that are currently used in industry. Silk fabrics treated by the scCO₂ degumming process are characterized by improved dyeing ability or color strength, while this process does not adversely affect the environment.

The author has developed a new approach to the degumming process exploiting a supercritical fluid carbon dioxide and found it as a good alternative to the conventional methods that are currently used in industry. Silk fabrics treated by the scCO₂ degumming process are characterized by improved dyeing ability or color strength, while this process does not adversely affect the environment.

As it is clearly seen from Table 1, the effectiveness of the degumming process can be improved by at least 38% applying scCO₂. Moreover, implementation of the scCO₂ silk degumming process into the textile industry may help manufacturers to consume less water and energy resources (Elmaaty and Abd El-Aziz, 2017), as well as to obtain pure sericin as a valuable end-product that can be used in the medical and cosmetic industries.

To make the silk manufacturing more green, the author has developed a technology for obtaining a plant-based indigo dye applying only locally grown agricultural products. The author has found that banana paste and banana peel paste have a sufficiently enough reduction potential for converting the indigo dye into indigo white, which is an important stage in the dyeing processes. The investigation performed showed that both these pastes can serve as a green alternative to sodium hydrosulfite, widely used in industry as a reducing agent. The main result of this study is the demonstration that natural, recyclable and easily biodegradable resources can be exploited to produce the semi-products for the textile industry and the final dyed silk fabrics as well. Summarizing the above, it can be concluded that we have got the results, which show promising alternative green processes for the textile industry in silk treatment (both degumming and dyeing). Their implementation may turn the silk textile production into a sustainable green circle and economically viable manufacturer.

This paper aims to determine the best conventional degumming technique for use by rural farmers practicing Eri silk fiber production in Kenya.

Three conventional silk degumming methods (water, soap and alkali) were analyzed under the factors, namely, time, pressure and degumming media, following the multilevel factorial design of experiments. The effect of variables on degumming weight loss was determined. The effects of the conventional degumming methods that produced complete sericin removal on chemical structure, surface morphology, thermal properties, crystallinity and fiber strength on Eri silk fibers produced in Kenya were then determined. The optimal degumming condition was then evaluated.

Soap and water degumming led to incomplete sericin removal. Alkali degumming media had the most effect, especially when pressure cooked at 103 kPa. Increasing time during alkali degumming beyond 30 min did not to have any major difference on degumming loss (at p 0.05). There were no major changes in chemical and thermal properties after degumming. However, the tensile strength and elongation deteriorated especially on alkali medium. Decreasing degumming time in alkali medium from 120 min to 30 min reduced the strength loss from 45% to 33%. Optimal degumming was found to be in an alkali media at 103 kPa for 30 min.

There is very little information available on Eri silk fibers produced in Kenya. Results of this study provide an optimized conventional degumming procedure suitable for small scale farmers in rural areas practicing Eri silk fiber production.

An improved multivoltine variety of Rajshahi silk fabric is used as material for investigation. This fabric is degummed to remove sericin, as sericin is soluble in hot water and highly responsible for the fading of dyed silk after washing. Rajshahi silk fabric is dyed with Reactive Brown 10 and Direct Orange 31 dyes. The color of the silk fabric becomes even and bright when it is dyed with 2.0% Reactive Brown 10 and 2.5% Direct Orange 31 after 50-60 minutes at 80-100°C. To achieve fast color, the silk fabric is treated with six modifying conditions prior to dyeing and among them, comparatively better modifying conditions are selected on the basis of color fastness upon exposure to sunlight in air and wash fastness in a soap solution. The modified Rajshahi silk fabric with 30% CH₃COOH and 20% tannic acid together show better dyeing properties than modifications with other conditions and unmodified silk fabric. Direct Orange 31 shows better colorfastness than Reactive Brown 10 after exposure to sunlight in air and also after washing with a soap solution.

The textile industry has consumed large quantities of water and discharged large volumes of wastewater in the dyeing process. The study aims to characterize self-dyed silk with Rhodamine B (RhB) for fashion applications to reduce textile hazards to the environment and increase the added value of silk.

Bombyx mori was fed with RhB-colored mulberry leaves (1500 ppm). The effects of self-dyeing were investigated via color strength K/S, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscope, X-ray diffraction, tensile strength, color fastness to washing, rubbing, perspiration and light.

Self-dyed silk possesses effective coloration and impressive color fastness (4–5/5), higher crystalline index (CrI) (73.26 ± 2.28%), less thermal stability and tenacity, slight change in amino acid composition compared with the pristine and no existence of harmful aromatic azo amines and arylamine salts.

The application of self-dyed silk with RhB dye has expanded new technology into fashion industry, contributing partly to economic growth and adding value to silk in the global supply chain. Besides, the self-dyeing will yield practical values in the reduction of dyeing discharge in textile industry.

Self-dyed silk was characterized for textile applications in comparison with pristine silk in terms of color strength and fastness as well as determined its polymeric properties relating to crystallinity, morphology, chemical composition, tensile properties and thermal stability which have not been investigated before.

Colorfastness properties of dyed degummed and dyed stannic chloride weighted silk fiber were studied as a function of exposure to sunlight in air, washing with soap solution and spotting with alkalis.

Improved multi-voltine variety of degummed silk fibers was weighted with the treatment of stannic chloride at the varying pH level. Maximum weighting of silk fiber was achieved at the optimum SnCl₄ concentration, pH of the solution, time and temperature. The degummed (un-weighted) and weighted silk fibers were then dyed with Direct Blue 1 and Direct Red 28 dyes at the optimized dying conditions.

The role of base (Na₂CO₃) on dyeing of weighted silk fiber with Direct Red 28 was found very influential. The loss in tenacity of degummed silk fiber was higher than that of SnCl₄ weighted silk fiber when they were exposed to sunlight in air.

The colorfastness of weighted dyed silk was comparatively higher than that of un-weighted dyed silk.

This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity.

Different nano- and bio-materials allowed for the development of a variety of biosensors – colorimetric, chemiluminescent, electrochemical, whole-cell and aptasensors – are described. The materials used for their development also make it possible to use them in removing heavy metals, which are toxic contaminants, from environmental water samples.

This review focuses on different technologies, tools and materials for mercury (heavy metals) detection and remediation to environmental samples.

This review gives up-to-date and systemic information on modern nanotechnology methods for heavy metal detection. Different recognition molecules and nanomaterials have been discussed for remediation to water samples. The present review may provide valuable information to researchers regarding novel mercury ions detection sensors and encourage them for further research/development.

Commercial natural dyes are quite costly as manufacturers are to follow multi-step extraction and purification procedures for standardisation purposes. Upon cost comparison, they lose in the market to synthetic dyes. However, in the handicraft sector, reproducibility may be of lesser importance against cost. In the present study, a domestic method of dyeing silk with the aqueous extract of raw plant/tree components (flower, leave, bark and root) by using a natural mordant and alum will be described. Good dyebath exhaustion and washing and light fastness are observed for some of the natural colouring matters.

Professor Newell in a recent statement has expressed the opinion that the ills to which farm live stock are subject, such as bovine tuberculosis—“a deficiency disease”—and foot and mouth disease can be traced back to the wrong treatment of the soil itself, from which spring the crops on which the stock are fed; and further, that bacteria which we understand from him are normally beneficient may by diseased conditions in the subject be transformed into malignant varieties to which the disease itself is wrongly ascribed. Diseased conditions in stock being in the first place induced by improper, or injudicious feeding, inadequate byre accommodation. foul water, and insufficient fresh air and sunshine. He goes to the root of the matter in more senses than one when he suggests, as we understand him to do, that the time has come for a thorough revision in our methods of soil and crop treatment. This, however, is a matter which concerns the specialist in these highly complex problems. As to the treatment to which live stock, and especially bovines, are too frequently subjected, it requires no expert knowledge to understand and to condemn it. We imagine that we follow the line of reasoning drawn by the Professor when we say that the incidence of bovine tuberculosis in our dairy herds at present has arisen from ill treatment, of the kind he describes, in the past, and this is all too prevalent at present. We only wish we could share his optimism when he states that bovine tuberculosis could be stamped out quickly by stock breeders and agriculturists giving their close attention to the points he mentions. That this would be far more than “a step in the right direction” we admit, but it implies that every cow keeper in the country has the requisite knowledge and the desire to apply that knowledge for the public benefit and quite conceivably at some considerable pecuniary loss to himself. As far as our knowledge of the matter goes the average cow keeper does not possess the requisite amount of altruism to make this even remotely possible.

The purpose of this paper is to prepare anionically surface‐modified organic pigment/binder ink jet inks for printing on chitosan‐pre‐treated silk fabrics.

Anionically surface‐modified organic pigment/binder ink jet inks were prepared in four colours (cyan, magenta, yellow and black). The pigment‐to‐binder ratio was controlled at 1:6.4 for the cyan, magenta and yellow inks, and 1:3.4 for the black ink. Ink formulations (by weight) were assembled and mixed as follows: 8 per cent pigment dispersion, 10 per cent diethylene glycol, 12 per cent glycerol, 5 per cent urea, 10 per cent polyacrylate emulsion binder and 55 per cent deionised water. They were characterised in terms of their particle size, zeta‐potential, particle morphology, viscosity, surface tension and pH. The inks were printed onto silk or the chitosan pre‐treated silk fabrics using a piezo‐type ink jet printer. The fabrics were then heat cured and analysed for the effect of chitosan pre‐treatment on colour gamut, wash fastness and crock fastness.

The formulated ink jet inks yielded an acceptably good ink jetting reliability, one‐year stability and printability. The chitosan pre‐treated silk fabrics gave a wider colour gamut and colour saturation than the non‐treated one. Crock fastness and wash fastness of the chitosan pre‐treated fabrics were relatively better than those of non‐treated fabrics.

The surface‐modified pigments are transparent and thus their inks printed on the chitosan pre‐treated fabrics produced slightly low K/S values of cyan, magenta, yellow, and black colours because the limited chitosan concentration in the pre‐treatment is controlled by its solubility in acidic solution. The higher loading of chitosan pre‐treatment gave higher K/S values and a stiffer touch of the fabrics.

The water‐based pigmented inks having the sulphonate group on the pigment surface can be printed on the fabric surface pre‐treated with chitosan molecules which have the protonated amino groups to give good colour appearance. It is anticipated that this type of ink can be applied to any textile surface which has been pre‐treated with the protonated chitosan.

The modified organic pigments having the sulphonate group on their surface can be used to produce novel water‐based ink jet inks which can print on the chitosan pre‐treated silk fabric. Ionic interactions between the sulphonate group of the pigment and protonated amino groups of chitosan in conjunction with polyacrylate binder enhance colour strength, widen colour gamut and chroma, and produce good adhesion for fabric operational properties such as wash fastness and crock fastness.

Wound healing is a dynamic process that relies on coordinated signaling molecules to succeed. Silk has proven to be a promising biomaterial for the development of a novel product. The purpose of the study is development of silk films, augmented functionality can be provided to silk by means of loading honey and recombinant human epidermal growth factor (rhEGF).

In this research work, the authors set out to explore possibilities of silk-based biomedical device development with particular attention to different fabrication strategies that can be leveraged for this purpose. They have produced a novel silk-based drug delivery material, in the form of silk films. Scanning electronic microscope was used to observe the morphology and the highly specific surface area. The structure was studied by Fourier-transform infrared spectroscopy. This methodology is accomplished using in vivo study data using Wister albonia rats.

The developed films also provided a significant higher healing rate in vivo, with well-formed epidermis with faster granulation tissue formation when compared to the controls. Biodegradable polymeric materials based on blending aqueous dispersions of natural polymer sodium alginate, Chitosan and rhEGF complex, which allow controlled antiseptic release, are presented.

These results suggest that silk-based controlled release of Chitosan-rhEGF may serve as a new therapy to accelerate healing of burn wounds.