• International Journal of Industrial Entomology and Biomaterials
• /
• v.33 no.2
• /
• pp.108-112
• /
• 2016

Silk has been used extensively in textile applications because of its good luster and feel. However, the low elongation and elastic recovery of silk has limited its use in a wider variety of textile applications. In this study, silk textile samples were made with a highly twisted silk/polyurethane core-spun yarn. They were immersed in water and dried at different temperatures, and the effect of treatment temperature on the mechanical properties of the silk textile was examined. It was found that the water temperature strongly affected the morphology and mechanical properties of the silk textile, whereas the drying temperature did not. As the water temperature was increased, the weft silk yarn became tangled and the interval between warp yarns decreased, resulting in shrinkage of the silk textile. When the silk textile was immersed in water at high temperature (i.e., $100^{\circ}C$), the elongation of the textile increased eight-fold as compared to an untreated silk textile. The maximum elastic recovery ratio of the silk textile was 96.7%.

• Textile Coloration and Finishing
• /
• v.14 no.1
• /
• pp.43-50
• /
• 2002

Silk/Cotton fabrics were treated with butanetetracarboxylic acid(BTCA) to improve crease recovery and anti-shrinking properties at various curing temperatures and pH values. We investigated the effects of finishing conditions on add-on of BTCA, bending property(E, 2HB), wrinkle recovery angle, shrinkage, and dyeing properties. The Add-on of BTCA increased with increasing curing temperature and concentration. Crease recovery was improved with decreasing shrinkage. Maximum add-on of BTCA was showed at pH 2.5. In case of dyeing and mercerization, silk side treated with BTCA was more flexible than untreated, whereas cotton side was more stiff. In dyeing after mercerization, B and 2HB values were higher and K/S values were doubled nearly. The hand of fabric improved with decreasing B and 2HB by the BTCA treatment. BTCA treatment after reactive dyeing improved crease recovery, and caused no change of color difference. However, BTCA treatment after reactive dyeing didn't improve crease recovery, whereas B and 2HB were decreased considerably by the treatment.

• Journal of Sericultural and Entomological Science
• /
• v.28 no.1
• /
• pp.61-65
• /
• 1986

This work was to realize the wrinkling behavior of spun silk fabric. The results were obtained through the various conditions such as temperature, wrinkling time, wrinkling load and crease recovery time. The obtained results were summerized as follows : 1. Wrinkle recovery of the silk fabric was decreased with the increase of temperature, humidity and the influence of humidity was superior to the influence of temperature. 2. The change of wrinkle recovery depending on the wrinkle recovery time showed the experimental equation (Y=a+b lnT). The wrinkle recovery increased with the lapse of wrinkle recovery time but arrived at the equilibrium position about 300 sec. 3. The value "K1" of the silk fabric in the "Voigt model" was inferior as compared with the polyester and Nylon. 4. The change of wrinkle recovery depending on the wrinkling time was decreased with the lapse of wrinkle recovery time but the change of the value "a" could not be fined. 5. The change of wrinkle recovery depending on the wrinkling load was same as above 4.

• Journal of Sericultural and Entomological Science
• /
• v.38 no.2
• /
• pp.138-143
• /
• 1996

Cooking of tasar silk cocoon of Deba variety (A. mylitta D.) with tartaric acid has been optimized by using an orthogonal central composite design. Shell weight loss and silk filament recovery are influenced by duration of treatment and acid concentration. Mechanical properties do not change with the process parameters. Hardness of water does not affect significantly the recovery of silk filament.

• Textile Coloration and Finishing
• /
• v.14 no.4
• /
• pp.249-258
• /
• 2002

Natural silk is formed by two proteins : the crystalline fibroin (inside the silk thread) and amorphous sericin (as a tube outside the thread). The degumming process is used to eliminate the external sericin prior to dyeing ; generally it makes use of soaps at about pH 10. Sericin is the protein constituent that "gums"together the fibroin filaments of cocoon silk. It constitutes about 25% of the weight of the cocoon, is soluble in hot water and "gels" on cooling. The removal of sericin from raw silk, known as degumming, is a simple but important process usually employing hot dilute soap or alkaline solution and occasionally dilute acids or enzymic methods. During degumming, alkali is taken up by the sericin and the free acid from the soap is formed ; this may be deposited on the fiber, reducing the rate of degumming and protecting it from hydrolysis. Alkali is often added to maintain or restore the pH of the baths, but it is rarely used alone, since it leaves the silk rather harsh in handle. If complete sericin removal is required as for printing, sodium carbonate may be added. If the pH of the bath exceeds 11, the fibroin is attacked. Recently, According to the development of electrolysis, we can be obtained the electrolytic reduction water(above pH 11.5) and electrolytic oxidation water (below pH 3). The aim of this work was to study a degumming process using electrolytic water and a possibility of sericin recovery. The new degumming process used electrolytic water operates at $95^\circ{C}$ for 2hr. without any reagents. The wastewater of this process are formed by a solution of sericin in water. This conditions suggest the study of a possible recovery of this protein (sericin) which has an amino acid composition suitable for many used in cosmetics, textile finishing agents, animal feeding, etc. The degumming process using electrolytic water is available to reduce treatment costs and pollute and at the same time to recover sericin.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.14 no.1
• /
• pp.23-32
• /
• 2007

The nature of genetic variation and diversity among the 65 multivoltine silkworm genotypes was evaluated for 16 post cocoon characters. The components of genetic variation revealed higher PCV (60.487%) and GCV (44.56%) for evenness (variation 1) followed by cohesion (PCV=55.38%, GCV=40.36%) and non-broken filament length (PCV=32.05%, GCV=31.28%). The higher heritability ($h^2$ in broad sense) was observed for boil-off loss (95.6%) followed by non-broken filament length (95.22%). The both genotypic and phenotypic correlation indicated significant positive correlation of filament length with non-broken filament length, silk recovery, raw silk, neatness, and low neatness; and negative correlation with denier, renditta and silk waste. The principal component analysis (PCA) revealed 75.381 % of total variance from the five principal components extracted. On the basis of Mahalonobis' $D^2$ values (Ward's minimum variance), the sixty-five multivoltine silkworm genotypes were classified in to 9 clusters with substantial inter and intra cluster distances. Number of genotypes included in different clusters varied from 3 to 17. The results indicated that the optimum distance obtained in cluster VII (15.059) along with higher cluster mean values especially for filament length, non broken filament length, renditta, silk recovery, silk waste, and raw silk emphasized the utilization of these genotypes in the conventional silkworm breeding programme for improvement of multivoltine silk fibre quality. The possibility of exploiting genetic variation in post cocoon traits for efficient breeding programme is discussed.

• Textile Coloration and Finishing
• /
• v.14 no.3
• /
• pp.19-25
• /
• 2002

Silk/cotton fabrics were treated with butanetetracarboxylic acid(BTCA) under various treating conditions such as concentration, treated time and curing temperatures. Bending property, tensile strength, wrinkle recovery angle, and shrinkage were measured. The BTCA concentration in the saponfication mixture was measured by an isocratic HPLC equipped with the strong cationic exchange column Aminex HPX-87-H and a UV detector. The detected concentration of BTCA was shown in silk side much more than that of cotton side. The bending and shrinkage properties were improved at minimum curing condition and the lower concentration of BTCA. Tensile strength decreased with increasing concentration of BTCA, curing temperature and treated time, while wrinkle recovery angle increased.

• Textile Coloration and Finishing
• /
• v.4 no.3
• /
• pp.122-130
• /
• 1992

To improve the physical properties and the dyeing properties of silk, the silk fabric was treated with urea resin and reactive dyeing. The effects of urea resin concentration, pH of padding bath and curing condition were investigated in order to find optimum condition and the following results are obtained The optimum condition for the crease recovery of silk fabric was urea resin concentration of 80 g/ι, pH of 7, the curings temperature of about 135$^{\circ}C$, and the curing time of 3 minutes. The crease recovery and the thermal insulation ratio of silk fabric were increased by the above treatment. K/S increased as the adding amount of Na$_2$SO$_4$ increased, K/S, however was not affected by the adding amount of Na$_2$CO$_3$. Co1or fastness of the dyed fabrics treated with urea resin were improved slightly compared with untreated ones.

• Journal of Sericultural and Entomological Science
• /
• v.41 no.3
• /
• pp.222-227
• /
• 1999

The weavability and bleaching of ramie/silk mixture fabrics were examined. When silk fiber was used as warp or weft in the mixture fabrics, the weaving properties became higher than that of ramile fabrics. Especially, the highest weavabiliy of mixture fabrics was obtained when used as warp silk fiber. The whiteness of ramie and tussah fiber treated with hydrogen peroxide, bleaching agent. was increased up to about 80% without significant changes of tenacity and elongation. As the increase of bleaching agent and treatment time, the whiteness of mixture fabrics was increased and the yellowness was decreased. Also, as the whiteness of mixture fabrics increased, the drape stiffness in warp direction was decreased but crease recovery was increased.

• Journal of Sericultural and Entomological Science
• /
• v.27 no.2
• /
• pp.28-39
• /
• 1985

The structural and useful characteristics of silk habutae treated with silicone resin by emulsion finishing method were studied. The results were obtained through crease recovery test, water repellency test, scanning micrograph observation, amino acid analysis, X-Ray diffraction analysis, and Fourier Transform Infrared Spectroscopy. The results are summarized as follows; 1) The improvement in crease recovery of silk habutae finished with silicone resin, was observed b soaping treatment and curing conditions. 2) The higher water repellency and stiffness in silk fabrics finished with silicone resin was found by the fabric inspection and the scanning electron microscopic observation. It is suggested that silicone resin impregnated into the void of silk fibroin. 3) The polar side chains of amino acid composition were decreased, when the silicone resin was treated on silk fibroin. 4) Through Amino acid analysis of silicone resin finished fibroin, the different amounts of amino acid composition was indicated due to silk fibroin silicone polymer reaction and the structural difference of its fibroin were also proved by X-ray diffractograms. 5) The functionality of the siloxane compound may be deduced from the silicone finished silk habutae by Fourier Transform Spectroscopy. It was concluded from the above results that the useful characteristics of silk fabric can be improved by silicone resin finishing.