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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.

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.

Silk is a highly valued animal fibre that has long been used to produce textiles of the finest quality. During the degumming process it losses almost 30% of its weight. The weighting of silk fibres with mineral compounds is an effective technique to counteract this loss in weight. Chemical modification by graft copolymerization of vinyl monomers is also effective.

Persian silk yarn was degummed using Marseille solution soap and graft copolymerized with 2-hydroxyethyl methacrylate (HEMA) in aqueous media by a redox initiator system. The percentage of HEMA in the feed varied from 0-100%. The grafting efficiency obtained was 70-90%.

The pH of the medium varied and its effect on the graft copolymerization was investigated. The grafted silk yarn gained in weight as the pH of the copolymerization medium was reduced and the time of copolymerization increased. Grafting affects the mechanical properties of yarn by reducing the tensile strength and slightly increasing the elongation of the yarn. The solubility in alkali solution improves as the yarn gains in weight. The infrared absorption (FTIR) spectra of the pure silk sample showed strong bands at 1540, 1635, and 1230 Cm^‒1, which are assigned to amid of I, II, III, respectively; and at 3417 Cm^‒1, which is assigned to OH. In the grafted samples, these peaks shifted to a higher wave number. The SEM studies were carried out to investigate structural properties of Persian silk yarn.

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.

Rapeseed is the only oilseed crop grown in the UK. This is now Britain's third largest arable crop with a total area of over 200 thousand hectares. Production of the seed has risen consistently and dramatically from 0.13 million tonnes in 1977 to 0.58 million tonnes in 1982. The dramatic rise in the crop is apparent from the wider spreading of golden yellow flower fields in our countryside during the spring. Last year, however, seed production was about 5% down due to a small decrease in yield of about 1 tonne/acre, on average. World production of rapeseed and mustard seed (related members of the Cruciferae family: B. campestris, B. napus and B. juncea) has also expanded over the last decade, and the combined crop now lies fifth in oil‐bearing seed production and ranks fourth in the world supply of edible vegetable oils after soyabean, palm and sunflower oils. As a result of EEC support for the crop, production of rapeseed in 1982 rose by 35% to 2.7 million tonnes in EEC countries.

FOLLOWING a method devised in collaboration with the Saskatchewan Research Council, the Western Oil Company Ltd., Moose Jaw, Sask., Canada, have used rapeseed oil successfully as a component of lubricating crease. The company has made 5,000 lb. of grease which is now being tested in bus fleets and in vehicles owned and operated by farmers, service station pro‐prietors and business men.

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.

As an efficient self-healing intelligent material, the encapsulation-based self-healing resin mineral composite (SHC) has a broad application prospect.

Aiming at the cracking performance of SHC, the dynamic load condition is employed to replace the traditional static load condition, the initial damage of the material is considered and the triggered cracking process and influencing factors of SHC are analyzed based on the extended finite element method (XFEM). In addition, the mechanism of matrix cracking and microcapsule triggered cracking process is explained from the microscopic point of view, and the cracking performance conditions of SHC are studied. On this basis, the response surface regression analysis method is used to obtain a second-order polynomial model of the microcapsule crack initiation stress, the interface bonding strength and the matching relationship between elastic modulus. Therefore, the model could be used to predict the cracking performance parameters of the microcapsule.

The interfacial bonding strength has an essential effect on the triggered cracking of the microcapsule. In order to ensure that the microcapsule can be triggered cracking normally, the design strength should meet the following relationship, that is crack initiation stress of microcapsule wall < crack initiation stress of matrix < interface bonding strength. Moreover, the matching relationship between elastic modulus has a significant influence on the triggered cracking of the microcapsule.

The results provide a theoretical basis for further oriented designing of the cracking performance of microcapsules.

This study aimed to Simultaneous matching of color and antimicrobial properties of silk fabric treated with silver nanoparticle. The antimicrobial finishing using silver nanoparticles (AgNPs) is one of the most important finishing processes in the textile industry. Color matching is widely applied in the textile industry, but there has been a need for the prediction of AgNPs concentration for the matching of dyed silver-treated samples.

In this research, the silk fabrics were dyed with various concentrations of C.I. Acid Red 359 dye at 0.5, 1, 1.5 and 2 per cent (w/w). The dyed fabrics were then coated with AgNPs in several concentrations at 0.015, 0.030, 0.050, 0.100 and 0.250 ml/l. The prediction of dye and AgNPs concentrations were evaluated using single constant color matching and artificial neural network techniques.

The obtained results indicate that the accuracy of dye concentration prediction, as well as AgNPs concentration prediction, was improved by using a neural network method. Also, the correlation between actual and predicted dye and AgNPs concentrations in the best neural networks is more than the single constant color matching method.

Simultaneous antibacterial and color matching of nanosilver-treated fabric is novel. This method achieved acceptable accuracy for antibacterial and color matching.