High Color Fastness Research Articles

Chitosan as a Thickener for Direct Printing of Natural Dye on Cotton Fabric

Development of chitosan as a thickener for direct printing of natural dye on cotton fabric was investigated. Chitosan was applied as a thickener at various concentrations and its effect on the print properties was determined in comparison with the typical printing thickener, sodium alginate. The results exhibited that chitosan affected the fabric properties by increasing fabric yellowness and stiffness. However, with increasing chitosan concentrations, the yellowness reduced only marginally. Direct printing on cotton fabric with 3% Natural Chestnut at varying chitosan concentrations showed that the optimum chitosan concentration for the printing was at 3%w/v, being equivalent to the viscosity of 17,800 mPa. The 3%w/v chitosan imparted the ultimate color yield, print outline sharpness and a minimal dye bleeding on the unprinted area of the fabric. Use of chitosan concentration higher than 3%w/v led to poor print properties on the fabric. The efficiency as a thickener of chitosan was found to be superior to sodium alginate. A high color yield and good color fastness properties on cotton fabric were rendered in the case of chitosan thickener at the same applied concentration with sodium alginate.

The production of lipopeptides by Bacillus subtilis with desizing wastewater and application in soaping process

AbstractIn this article, a low‐cost medium for the production of lipopeptides by the Bacillus subtilis HSO121 was formulated with desizing wastewater as carbon source, which contains starch and its degradation products, and the lipopeptides were biosynthesized. As the result, the yield of crude lipopeptides was 1.03 g/L, and the critical micelle concentration was ∼ 50 mg/L. The chemical oxygen demand of the desizing wastewater after cultivation reduced to half compared with before cultivation. Separation of crude lipopeptides and its application as soaping agents in soaping process were investigated. The optimal soaping process was obtained at pH = 9 and 75°C with 0.05 g/L lipopeptides. Compared with traditional soaping process, lipopeptides soaping showed higher efficiency and higher colorfastness, and it is more energy efficient and more environmentally friendly process. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Optimization of oligourethane methacrylate based UV paints composition for printing on cotton fabrics

The effect of structure and content of the main components of UV paints (disperse dyes and pigments, photoinitiators, oligomers, cross-linking agents) and some auxiliary substances on photosensitivity of paints and color fastness are studied. Optimization of the composition of UV paints containing disperse dyes offers smaller color variation in UV drying and provides high color fastness to wetting and rubbing. A disadvantage of UV paints based on disperse dyes, is the relatively low fastness to light, which may be overcome by substituting the latter by organic pigments. For more optimal correspondence to other modern technologies of pigment printing, the use of emulsion UV paints is suggested. Such paints provide materials with good hygroscopic properties, improved physicomechanical characteristics and high color fastness.

감물을 이용한 천염염색과 염직물 특성

The natural dyeing of fabrics with persimmon juice(astringent persimmon, sweet persimmon, astringent and sweet persimmon mix) was investigated. After dyeing of cotton and silk fabrics with persimmon juice, we evaluated the dyeability of persimmon juice, the observation of fabric surface with high magnification video microscope, physical properties and color fastness with the conditions of repeating times of dyeing and variables of mordants. The results obtained from this study were as follows: The fabrics dyed with astringent persimmon have shown the highest color difference, while the fabrics dyed with sweet persimmon and the fabrics dyed with astringent and sweet persimmon mix have shown similar color differences. With the increase of repeating times of dyeing, the brightness of fabric decreased. However, <TEX>$a^*$</TEX> value increased gradually, so that it became dark brown color. The <TEX>$a^*$</TEX> and <TEX>$b^*$</TEX> values of dyed fabrics with Fe-mordant have dropped significantly, so that they have shown achromatic colors. But the fabrics treated with other mordants have shown yellowish brown colors. On the surface of the fabrics, threads were bonded together by the viscosity of persimmon juice. Regardless of the types of persimmon juice, stiffness was increased after dying, while crease resistance was decreased. The water repellency of silk fabrics were improved than cotton fabrics after dyeing with sweet persimmon juice, but in case of cotton, it hasn't changed. Washing fastness was improved with the EM(Effective Microorganism)-fermented liquid treatment, and rubbing fastness of two fabrics was better in dry condition than in wet condition.

Interpretation of the C1s XPS Signal in Copper Phthalocyanine for Organic Photovoltaic Device Applications

AbstractCopper phthalocyanine (CuPc) belongs to a class of small molecules offering particularly interesting advantages when employed in organic electronic devices. Because of its advantageous attributes like high thermal stability, inertness when exposed to acids or alkalis, relatively high electron conductivity, color and light fastness it has been employed in polymer photovoltaic devices as a unipolar dopants complementing the buckminsterfullerene (C60) acceptors and as a conductive buffer. Other organic applications include ambipolar OFETs and non-linear optics structures. X-ray photoelectron spectroscopy (XPS) has been commonly employed to monitor the quality of thin CuPc films. Although XPS analyses of CuPc have been done for over forty years there has not yet been agreement regarding interpretation of the major C1s signal, particularly in the case of non-stoichometric CuPc composition. This work presents systematic studies of the C1s signal of thin film deposits, fabricated using commercially available CuPc materials. It was found that composite C1s CuPc signal consists of five components: two related to the principal C positions within the CuPc macrocycle (C-C in 6-membered ring, C-C-N in 5-membered ring), two associated with shake-up transitions accompanying principal C transitions, and one due to mostly aliphatic impurities. Detailed analysis showed that the magnitude of shake-up peaks was approximately equal 10% to 12% of their principal transitions, in agreement with the theoretical calculations. Correspondingly, the C1s signal originating from the non-CuPc impurities quantitatively agreed with the IR attenuated total reflectance (ATR-IR) measurement of the C-H aliphatic vibrations originating from these impurities present within the CuPc layer. The proposed C1s interpretation has been successfully tested for a large number of commercial CuPc materials and provides a guideline for a routine XPS analysis of the CuPc in organic photovoltaic devices.

Estimation of Main Constituents of Ananus comosus (Pineapple) Leaf Fiber and Its Photo-Oxidative Degradation

An estimation of main constituents of pineapple leaf fiber (PALF) by conventional method was attempted and the values of 74.44% α-cellulose, 13.39% hemicellulose, 7.12% lignin, 2.89% pectic matter, and 0.58% aqueous extract were obtained. So, the main constituents of PALF are α-cellulose, hemicelluloses, and lignin. The molecular weight of raw, bleached PALF and α-cellulose of PALF were 1.517 × 105, 1.303 × 105, and 1.225 × 105, respectively. Bleached PALF was dyed with two dyes, Direct Green 27 and Acid Orange 52. Maximum dye exhaustion was found to be 98.97% for Direct Green 27 under the conditions of 3% dye concentration, 5% electrolyte concentration, and 70°C temperature, and 93.27% dye exhaustion was found for Acid Orange 52, where dyeing conditions were 4% dye concentration, 6% electrolyte concentration, and 80°C temperature. Dyeing time was fixed for 60 min for both dyes. The color fastness of PALF on exposure to sunlight has also been studied. It was observed that color fastness of raw fiber is higher than bleached fiber. The degradation of PALF under sunlight was studied by tensile strength and molecular weight measurements. Bleached fiber exhibited lesser loss of tensile strength and molecular weight than raw fiber. Infrared spectra (IR) of PALF were measured for different exposure times under sunlight. The PALF containing higher α-cellulose has good characteristics, similar to materials of higher molecular weight. For this, it gives high tensile strength, more dyeability, and better color fastness properties.

Methylphloroglucinol as an available semiproduct for azo dye synthesis

A technologically convenient method is suggested for the high-yield synthesis of 2,4,6-trihydroxytoluene (methylphloroglucinol) from 2,4,6-trinitrotoluene. A number of structurally different azo dyes have been synthesized. The dyes are applicable to various textiles, ensuring high colorfastness to laundering and rubbing.

Plasma Deposition of Amine-Embedded Nanoporous Ultrathin Films on Polyester Enables Substrate Independent Surface Dyeing

The paper describes the work of developing an original process of plasma deposition of nanoporous functionalized coatings, which was applied to polyester (PES) textiles enabling substrate independent surface dyeing. This novel approach is essentially based on a fine control of rivaling deposition/etching processes during plasma co-polymerization of ammonia with hydrocarbons at low pressure and at low temperature. A nanoporous structure with a large surface area was achieved that contained functional groups inside the coating volume, which were accessible to dye molecules, thus facilitating substrate independent surface dyeing. Depending on the gas ratio, a crosslinked and branched hydrocarbon network yielded excellent mechanical properties and a durable coating as indicated by the high color fastness to washing of the dyed textiles. The dyeing time can be reduced remarkably due to the porous nanoscaled coatings. Since amine-embedded functionalized films were deposited, it was possible for acid dyeing to be applied to the PES at low temperatures.

Use of azoic dyes for dyeing Terlon fibre

The use of components for formation of azoic dyes in certain stages of fabrication of Terlon fibres allows obtaining dyed fibres with high color fastness and preservation of the basic physicomechanical properties of the fibre.