Preparation and properties of cotton and wool fabrics dyed by black rice extract

Abstract

Black rice is known as a health-promoting food for its abundant content of anthocyanins. Anthocyanins possess various functionalities, such as antioxidant, antibacterial, anti-tumor, and anti-inflammatory effects. However, they are easily wasted during the cooking process since they are water soluble pigments. Thus, the aim of this study was to use the black rice extract produced from the cooking process as a natural pigment and functional agent for textile finishing. In this study, wool and cotton fabrics were dyed by the black rice extract and the dyed fabrics were investigated by various analyzers. For cotton fabric, cationization was conducted before the dyeing process. The results revealed that wool and cotton fabrics were colored in reddish brown through the dyeing process. In addition, the wool and cotton fabrics dyed by black rice extract showed superior colorfastness in drycleaning and washing conditions compared to fabrics dyed by other natural pigments. In particular, the wool and cotton fabrics dyed by black rice extract possessed antibacterial and antioxidant characteristics. It was further observed that the functionality was increased by repeating the dyeing process.

An innovative approach to the preparation of coloured and multifunctional silk material with the natural extracts from chestnut shell and black rice bran

“…Moreover, a weak band at 280 nm was observed in the spectrum of the black rice bran extract, which was due to the electron excitation from π→π* transition in the benzene system of cyanidin‐3‐glucoside . These results demonstrate the presence of aromatic fragments in the chemical structure of the natural extracts .…”

“…As can be seen in Figure , the spectra of both chestnut shell and black rice bran extract showed an intensive band at 230 nm, which was due to chromophores, including the C=C and C=O bonds of various compounds as well as the benzene ring in ellagic acid and cyanidin‐3‐glucoside of the natural extracts . Moreover, a weak band at 280 nm was observed in the spectrum of the black rice bran extract, which was due to the electron excitation from π→π* transition in the benzene system of cyanidin‐3‐glucoside . These results demonstrate the presence of aromatic fragments in the chemical structure of the natural extracts .…”

“…Large quantities of chestnut shell are produced during chestnut processing, which can be regarded as a new source of brown natural pigments and functional finishing agents. Black rice colorant with the major constituent of cyanidin‐3‐glucoside (C3G) (Figure b) belongs to the family of anthocyanin pigments and mainly exists in the seed coat of black rice. It has already been shown to have various functionalities, including antioxidant, antibacterial, antitumour, and anti‐inflammatory properties.…”

Effects of tannin mordanting on coloring and functionalities of wool fabrics dyed with spent coffee grounds

“…Meanwhile, the values of color fastness to light, which is a major problem for fabrics dyed with natural colorants, were significantly lower than those obtained for color fastness to washing. However, the level of color fastness to light for the wool fabrics dyed with spent coffee extract was observed to be higher compared to that of other fabrics dyed with other natural colorants (Hong 2015;Koh and Hong 2017b). In particular, the color fastness to light improved significantly with increasing tannin concentration during the mordanting process.…”

Optimized Dyeing Process for Enhancing the Functionalities of Spent Coffee Dyed Wool Fabrics Using a Facile Extraction Process

“…Considering the color fastness of the wool fabrics dyed with the spent coffee extract and mordanted with tannic acid, the wool fabrics showed a high level of color fastness to washing (4.5 grade); in contrast, they exhibited somewhat inferior color fastness to light (3–4 grade), as shown in Table 2. However, it was found that the levels of color fastness of the wool fabrics dyed with the spent coffee extract and mordanted with tannic acid may be higher overall than those of fabrics dyed with other natural pigments [19,20].…”