Due to its relatively large specific surface area and microporous structure, bamboo charcoal is widely employed in a variety of industries, including the textile sector. In this investigation, bamboo ...charcoal powder was formulated as a natural colorant in the pigment print paste and then applied to cotton fabric by screen printing. Colorimetric values were assessed and color fastness to washing, light, and crocking as well as mechanical properties was performed according to related standards. By varying the amount of bamboo charcoal, the printed fabric had a light to dark gray color with good to excellent wash, light, and crock fastness. The combination of binder and fixing agent in the print paste increased fabric tensile strength, elongation, tear strength, and more pronounced stiffness. Besides, the bamboo charcoal printed cotton exhibited a deodorizing rate of 80.3-87.8% against ammonia gas after 40 min and was maintained at 54.8-73.1% after 10 washing cycles.
In this investigation, dyeing of cotton fabric with natural dye extracted from purple corncob was attempted by means of pretreatment with a cationic agent, 3-chloro-2-hydroxypropyltrimenthylammonium ...chloride (CHTAC). Maximum color yield results were achieved when the fabric was pretreated with CHTAC at a concentration of 125 g/L, followed by dyeing at 100°C for 30 min in a dye bath adjusted to pH 9. The influence of meta- and post-mordanting with AlK(SO
4
)
2
, CuSO
4
, FeSO
4
, and gallnut was subsequently explored. Compared with the unmordanted sample, post-mordanting enhanced K/S values and slightly improved light fastness, but both meta- and post-mordanting caused a reduction in wash fastness from an excellent to a fair level, with the exception of CuSO
4
. Meanwhile, mordanting with gallnut increased the acid and alkaline perspiration fastness from a poor and fair to a good level.
Natural dye extracted from mangrove bark was applied to a silk fabric by an exhaustion dyeing process. Aluminum potassium sulfate, ferrous sulfate, copper sulfate, and stannous chloride were used as ...mordants. The dyeing was conducted with and without metallic salt mordants, using three different mordanting methods: pre-mordanting, meta-mordanting, and post-mordanting. The color of each dyed material was investigated in terms of the CIELAB (L*, a* and b*) and K/S values. The color fastness to washing, crocking, perspiration, and water of the dyed samples was determined according to AATCC test methods, whereas the color fastness to light was tested according to the ISO standard. Optimum results were achieved when dyeing at 90°C for 60min and at pH 3. Silk fabric dyed without mordant had a shade of reddish-brown, while those mordanted with stannous chloride, aluminum potassium sulfate, and copper sulfate produced a variety of pale to dark reddish-brown color shades. However, duller and darker shade was obtained with ferrous sulfate mordant. The color fastness to washing was mostly very poor to poor but there was no fading of the color, whereas the color fastness to light and crocking were mostly fair to good level. However, the perspiration and water fastness results showed good to very good levels, except for fabric mordanted with ferrous sulfate, whose color change rating was poor to fair for perspiration fastness. Tensile strength, tearing strength and stiffness of the fabrics before and after dyeing were also evaluated.
Natural colorant extracted from the fruit shell of Camellia oleifera was applied to PP spunbond nonwoven fabric by pigment printing method. The printing pastes containing natural dye, a thickener, an ...acrylate binder, and ferrous sulfate were applied to the substrate via flat screen technique. The printed fabrics were evaluated in terms of colorimetric measurements, color fastness properties as well as mechanical behaviors. The increase in color strength and the change in color hues from light brown to greyish black were observed by varying the amounts of dye, binder and ferrous sulfate. Increasing binder concentration led to an improvement in tensile strength and elongation in most cases, but had a negative impact on tear strength. The printed nonwoven possessed fair to moderate light fastness and fair to excellent crock fastness.
Purpose
The purpose of this study is to investigate the possibility of dyeing polyester (PET) fabric with natural dye extracted from annatto seeds using high temperature dyeing method.
...Design/methodology/approach
PET fabric was dyed with annatto extract by varying dyeing parameters (temperature, time, pH and dye concentration) to determine the optimum dyeing conditions. The influences of KAl(SO4)2, FeSO4, gallnut mordants or a commercial UV absorber on colour yield and fastness properties were further studied.
Findings
Optimum results were obtained when the fabric was dyed at 130°C for 30 min in a dyebath containing 15 per cent (owf) annatto dye at pH 6. The dyed fabric had an orange shade and exhibited good to excellent wash, crock, perspiration fastness and fair light fastness. Further dyeing with mordants or UV absorber mostly resulted in lower colour yield and similar fastness properties.
Research limitations/implications
Although the light fastness was slightly improved to moderate level for the sample with UV absorber, a noticeable colour staining on cotton portion of multi-fibre fabric occurred when subjected to standard washing test. Compared to C.I. Disperse Orange 73, the annatto dye exhibited comparable colour fastness but had inferior light fastness when dyed at approximately the same colour strength.
Originality/value
Natural colourants from annatto seeds can be used to dye PET fabric at high temperature without mordants, yielding deep orange shade and satisfactory fastness properties. This study provides a promising application to reduce the environmental impact of synthetic dyes.
Removal of non-cellulosic impurities from cotton fabric, known as scouring, by conventional alkaline treatment causes environmental problems and reduces physical strength of fabrics. In this study, ...an endo-polygalacturonase (EndoPG) from Aspergillus aculeatus produced in Pichia pastoris was evaluated for its efficiency as a bioscouring agent while most current bioscouring process has been performed using crude pectinase preparation.
The recombinant EndoPG exhibited a specific activity of 1892.08 U/mg on citrus pectin under the optimal condition at 50 °C, pH 5.0 with a V
and K
of 65,451.35 μmol/min/mL and 15.14 mg/mL, respectively. A maximal activity of 2408.70 ± 26.50 U/mL in the culture supernatant was obtained by high cell density batch fermentation, equivalent to a 4.8 times greater yield than that from shake-flask culture. The recombinant enzyme was shown to be suitable for application as a bioscouring agent, in which the wettability of cotton fabric was increased by treatment with enzyme at 300 U/mL scouring solution at 40 °C, pH 5.0 for 1 h. The bio-scoured fabric has comparable wettability to that obtained by conventional chemical scouring, but has higher tensile strength.
The work has demonstrated for the first time functions of A. aculeatus EndoPG on bioscouring in eco-textile processing. EndoPG alone was shown to possess effective scouring activity. High expression level and homogeneity could be achieved in bench-scale bioreactor.
Purpose
The present study aims to focus on the feasibility of using an aqueous extract from the fruit shell of Camellia oleifera Abel as a source of natural colourant in printing-paste preparation ...for pigment printing of cotton fabric. The effects of pre- and post-mordanting with three common metallic mordants, that is AlK(SO4)2, CuSO4 and FeSO4 on colour yield and colour fastness properties are also investigated.
Design/methodology/approach
The printing paste was prepared by mixing the concentrated Camellia oleifera Abel fruit shell extract solution with commercially available synthetic thickener and binder. The fabric sample was printed with the prepared printing paste using a flat-screen printing technique. To determine the effects of pre- and post-mordanting, AlK(SO4)2, CuSO4 and FeSO4 mordant aqueous solutions with various concentrations were applied using the pad-dry technique. Comparisons between printing with and without mordants were evaluated in terms of colour strength (K/S values) and colour fastness to washing, light, crocking and perspiration.
Findings
Without the mordants, the printed fabric had a yellowish brown shade with acceptable colour fastness properties, that is fair to good wash fastness, moderate light fastness, good to very good crocking fastness and fair to good perspiration fastness. The use of mordants, especially CuSO4 and FeSO4, not only enhanced colour strength but also imparted different colours to the fabric. Compared to the unmordanted fabrics, colour fastness properties were mostly comparable or improved in the mordanted fabrics depending on the type and concentration of mordants.
Research limitations/implications
Although in the case of CuSO4 the light fastness was increased to a good to very good level, it is recommended that the final print be produced with a concentration of less than 0.125 gL−1 to yield the print with the residual amount of Cu metal under the limit, that is less than 50 ppm as regulated by the Oeko-Tex® standard.
Practical implications
The obtained prints from Camellia oleifera Abel fruit shell extract provided shades with satisfactory colour fastness to washing, light, crocking and perspiration. The extract from Camellia oleifera Abel fruit shell has the potential to be used as an alternative to synthetic dye in the textile industry.
Originality/value
The use of Camellia oleifera Abel fruit shells, which are considered as abundant byproducts of tea seed oil production, as natural colouring agents for pigment printing of cotton fabric has been reported for the first time. It will minimise the environmental impact of this waste and create more valuable textile products.
A natural colorant obtained from extraction of mangrove bark was applied on nylon fabrics via exhaustion process. Colorimetric data (CIE L*, a*, b* and K/S) were evaluated. Pre-, meta-and ...post-mordanting with different metal mordants (aluminium potassium sulfate, ferrous sulfate, copper sulfate, and stannous chloride) were also investigated. The colorant extracted from mangrove bark shows affinity to nylon fabric dyed without mordants. The highest color yield and uniform dyeing were obtained with post-modanting method.
Investigation of dyeing parameters (temperature, time and pH), color fastness assessments and ultraviolet protection factor (UPF) of mangrove bark extract on nylon fabric were conducted. The optimum ...dyeing conditions were obtained at 90°C, 60 min and pH 5, respectively. Dyeing with different metal mordants (aluminium potassium sulfate, ferrous sulfate, copper sulfate, and stannous chloride) was also investigated. The ratings of color fastness testing showed that most of color fastness properties of dyed fabrics were generally acceptable except color fastness to washing due to considerable change in color of samples after subjected to washing test. Dyed nylon fabrics showed the improvement in UV-protection property.