• Textile Coloration and Finishing
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• v.16 no.4
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• pp.10-18
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• 2004

In this work, Aqueous sericin solution was prepared by degumming process with electrolytic reduction water. Then, the microfiltration and ultrafiltration systems were applied to the concentration of aqueous sericin solution. The objective of this study was to select the optimum operating condition among the different pressure. The permeate flux and rejection ratio were observed with time, pressure, flow rate and concentration. and, the wastewater and permeated water quality values such as pH, BOD, COD, and NH levels were measured. In order to see the influence of electrolytic reduction water, the flux of pure water and electrolytic reduction water by PVDF22(MF) and PS100(UF) membrane was measured. In microfiltration system, the relative flux reduction decreased rapidly to 0.02 in the 30min, as the concentration polarization and gel layer formation were increased. and then the sericin concentration rejection ratio was 40%. In ultrafiltration system, the permeate flux decreased with time and concentration, and increased with the operating pressure and flow rate. Optimal condition in PS100 membrane system for sericin concentration was operating pressure 1.464kgf/$cm^24, operating flow rate $7\ell/min at\; 40^{\circ}C$. At that time, sericin concentration rejection ratio was 83% respectably. The sericin solution was concentrated from 0.1wt% solution to 0.2 wt % solution during about 2 hrs by the UF filteration membrane system.

• Journal of Sericultural and Entomological Science
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• v.44 no.1
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• pp.37-41
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• 2002

The attaching treatment of sericin onto polyester fiber was attempted to improve its sanitary properties. Generally, sericin, a gummy material covering the outer layer of silk filament, is subjected to be removed during degumming process of silk textile process. For this study, sericin particle dissolved within the degumming waste water could be collected by sedimentation of polyaluminium chloride. It was revealed that sericin particle were attached onto the surface of polyester fiber evenly by treatment of glutaraldehyde, a crosslinking agent. A frictional static charge of the treated polyester fabric could be improved, while its hygroscopic property was little changed.

• Journal of Sericultural and Entomological Science
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• v.36 no.1
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• pp.37-43
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• 1994

The effects of some sodium phosphates as auxiliary agents were studied on the blockade of hardness for silk degumming. In this work, four kinds of sodium phosphates were tested and the results were obtained through masking effects of metallic ions, difference of pH value and boil-off ratio. The degumming of calcium ingredient was analyzed by means of atomic absorption spectrophotometer and degumming test of cocoon shell was performed in the presence of calcium ingredient and sodium phosphates added to soap solution. In the view of the effects of sodium phosphates on calcium hardness, tetrasodium pyrophosphate(TSPP) and sodium phosphate dibasic(SPD) masked calcium ions more than sodium phosphate monobasic(SPM) and sodium hexametaphosphate(SHP). SHP and TSPP have excellent abilities of masking ferrous ions. The pH values of TSPP solution is higher than others, but lower than soap solution. The pH values were differently measured one another among the sodium phosphates but the boil-off ratio was increased in case of sodium phosphate with high pH value.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.93-98
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• 2017

The fixing behaviors of raw silk yarns treated with melamine and formaldehyde at a molar ratio of 1:3 for trimethylolmelamine were investigated. Sericin was fixed during the fixing process, but a part of sericin I was removed simultaneously by hot water. The weight losses by fixing and the degumming losses by degumming greatly decreased with increasing concentrations of melamine and formaldehyde. The silk yarns fixed with 0.011 M melamine and 0.033M formaldehyde were significantly degummed due to the insufficient fixation of sericin and the alkaline hydrolysis of sericin by sodium carbonate during the degumming process. On the other hand, the silk yarns fixed with 0.055M melamine and 0.165M formaldehyde were degummed slightly (the degumming losses of 3-8%) due to the strong fixation of sericin, which might result from the many cross-linkages between the sericin I molecules, which were formed by trimethylolmelamine. Those fixed with the fixing solution containing 15% owf softener showed the lowest weight and degumming losses because under the condition of 15% owf softener, the cation of the softener can effectively form ionic bonds with the negatively charged side chain of aspartic acid in sericin. In addition, van der Waals' forces may be also formed between the hydrophobic tail of the softener and the hydrophobic region of sericin, which may help inhibit the removal of sericin I.

• International Journal of Industrial Entomology and Biomaterials
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• v.27 no.1
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• pp.203-208
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• 2013

Sericin is usually abandoned after the degumming process. However, it could be a valuable bioresource if an economically efficient recovery process could be set up. In this study, sericin was recovered directly from the degummed waste solution by adding calcium chloride, which induced the precipitation of the surfactant, sodium oleate, by charge interaction. The recovery yield was maximum when 10% of calcium chloride was added. Further increase in the calcium chloride concentration induced the precipitation of sericin. The recovered sericin had a molecular weight distribution similar to that of the hot-water-extracted sericin; but some highmolecular- weight sericin could not be recovered. The secondary structure and amino acid composition of the recovered sericin were similar to those of conventional hot-water-extracted sericin. We expect that sericin recovered from the degummed waste solution could be an alternative to the hot-water-extracted sericin, which is widely used in various applications.

• Korean Journal of Food Science and Technology
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• v.13 no.2
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• pp.160-164
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• 1981

A study was conducted for process conditions for maximum yield of crude soy lecithins and its quality improvement by solvent extraction. Results indicate that maximum yield of the crude lecithins was obtained by hydration with 3% water at degumming temperature $75^{\circ}C$. On the other hand, water level used for hydration was found to affect the recovery yield of the lecithins more profoundly than the degumming temperature. It was also found that extractions with acetone and 2-propanol increased the phosphatidyl choline content from 19.7% to 28.3% and 58%, respectively.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.155-158
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• 2002

세리신은 피브로인과 거의 같은 아미노산으로 이루어져 있으며 피브로인에 못지않게 그 활용이 기대되는바 화장품의 보습제, 식ㆍ음료의 첨가제, 생약제, 섬유가공제등 많은 분야에 이용되고 있다. 그러나 세리신의 회수에는 견 섬유의 주용도인 섬유 (피브로인)로서의 목적을 충족시키면서 부수적으로 세리신을 회수해야 한다는 큰 어려움이 있다. 즉 견섬유를 정련하여 세리신을 제거하는데는 주로 비누/알칼리 정련법이 이용되고 있으나 이 방법으로 정련을 하면 세리시이 가수분해하여 저분자화하기 때문에 그 회수가 어려워진다. (중략)

• Journal of Sericultural and Entomological Science
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• v.41 no.3
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• pp.205-210
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• 1999

Silk nonwoven fabrics are prepared by needle punching and thermal bonding with silk waste. To enhance the carding efficiency, the degumming rate was controlled with sodium hydrogen sulfite solution. The amount of the remained sericin was 3%(S-3), and 6%(S-6). Mixing wool and LMP(Low melting polyester) with the silk, to improve carding efficiency, was also effective. Following items were tested with prepared silk nonwovon fabrics : weight, thickness, compression, tensile strength, heat insulation, water absorption, and deodorization. The results show that the silk nonwoven fabrics could be used for apparels and new biomaterials.

• Journal of Sericultural and Entomological Science
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• v.25 no.2
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• pp.44-50
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• 1984

The effects of sodium pyrophosphate, sodium tripolyphosposphate and ethylene diamine tetraacetic acid as a degumming aid reagent were investigated under the conditions of underground water and dimineralized water for the scouring water sources. The changes of water qualities by adding the condensed sodium phosphates and the physical properties of scoured silk fabric were examined, respectively. 1. The water hardness of underground water was decreased by adding the condensed sodium phosphates and it was further reduced according to the increasing temperature. The water hardness reducing power of sodium pyrophosphate was a little stronger than that of sodium tripolyphosphate. 2. The sodium silicate as an alkaline reagant for scouring decreased the water hardness, but the sodium carbonate increased it in the underground water. 3. The pH value of 0.4% soap and 0.25% sodium silicate mixed solution after boiling was. 9.80, but it was leveled upto 9.90 by adding 0.05% sodium pyrophosphate and upto 9.95 by 0.02% ehtylene diamine tetraacetic acid, respectively. 4. The masking action of Fe$\^$3+/ ions dissolved in the scouring water was more remarkable by ethylene diamine tetraacetic acid than by the condensed sodium phosphates. Of the condensations, sodium tripolyphosphate was more effective than sodium pyrophosphate in the action. 5. Genrally, the dimineralized water scouring increased the boil-off ratio with reducing the flexural rigidity of fabric which was negatively related with the favorablility of hand-touch more than the underground one did. 6. Under the underground water scouring, the addition of ethylene diamine tetraacetic acid increased the boil-of ratio and compressive elasticity of fabric with reducing the flexural rigidity more than that of the condensed sodium phosphates did. 7 The additions of sodium tripolyphosphate and ethylene diamine tetraacetic acid reduced the flexural rigidity of fabric with raising the boil-off ratio even in the dimineralized water scouring, but there was no sifnificant difference between both of them.

• Journal of Sericultural and Entomological Science
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• v.43 no.1
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• pp.41-48
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• 2001

The purification, dissolution and powdering of stained waste silk obtained from weaving and dyeing process were studied for the surface modification of textile fabric and plastic materials. The whiteness of stained waste silk could be improved through degumming and bleaching with sodium hydrosulfite. The water-soluble fibroin solution can be obtained by dissoving the degummed waste silk in a boiling solution of 50% calcium chloride for 60 minutes. The salts and heavy metals contained in fibroin solution were removed by electric dialysis, wool fiber filtration and gel filtration chromatography. The fibroin powder was prepared by using a fine grinder after the alkali treatment for weakening the silk fiber. The fine fibroin powder of particle size around 30 ㎛ was obtained with a ultra fine-mill, while it was finer below 10 ㎛ with a ball-mill. The dissolved or powdered silk was applied to the surface of fabric with addition of the binder (a urethane resin). The moisture content of polyester and nylon fabrics treated with the silk solution was improved due to hygroscopic property of silk. The fine fibroin powder mixed with the binder ws coated on the surface of synthetic film by use of the air pressed sprayer. It was revealed that the hygroscopicity as well as the softness of fibroin powder coated film was much improved. Therefore, it is thought that the fine silk fibroin powder is applicable as an coating agent for the surface modification of plastic and synthetic leather.