Eco-dyeing with biocolourant based on natural compounds

Abstract

Biomass pigments have been regarded as promising alternatives to conventional synthetic dyestuffs for the development of sustainable and clean dyeing. This investigation focused on in situ dyeing of fabrics with biopigments derived from tea polyphenols via non-enzymatic browning reaction. The average particle size of dyed residual liquor with natural tea polyphenol was 717.0 nm (ranging from 615.5 to 811.2 nm), and the Integ value of dyed wool fabrics was the greatest compared to those of counterparts. In addition, the Integ values of dyed fabrics with residual liquor were much bigger than those with the first reaction solutions when dyed by identical dyeing liquor. As a result, the dyeing process could be carried out many times because the concentration of the residual liquor was relatively superior. All dyed fabrics acquired admirable rubbing as well as washing fastness, and the relevant dyeing mechanism has been analysed in the paper.

Mordant Free Dyeing and Functionalization of Wool Fabrics with Biocolorants Derived from Apocynum venetum L. Bast

“…After being adsorbed on the surface of the wool, pigments penetrate into the inner layer of the fibers. According to the pore model, the natural hydrophilic wool can be regarded as a solid containing networks of interconnecting channels or pores . Dye molecules diffuse into these pores and are simultaneously adsorbed onto the pore’s surfaces.…”

“…With ever-increasing concerns on ecosafety and human health issues, the utilization of renewable and sustainable biomass resources has become a universal research theme. , Natural dyes, obtained from plants, have been extensively used for the coloration of textiles with fascinating properties such as being biodegradable, ecological, renewable, nontoxic, and nonallergic. − Since flavonoids are naturally occurring pigments, which are highly diversified and are ubiquitous to vascular plants, as well as easily separable with traditional separation methods, researchers have long used these compounds as dyes for dyeing processes. , However, some inherent disadvantages like poor color depth and low colorfastness of the dyed textiles limit their use in modern-day applications. , To overcome these problems, metallic mordants are usually employed by meta-, pre-, and postmordanting procedures . The most commonly used mordants include potassium dichromate, aluminum potassium sulfate, ferrous sulfate, stannous chloride, and copper sulfate .…”

Phenolic Compounds from By-Products for Functional Textiles

“…Thus, a need has risen to move the textile industry towards a sustainable circular economy [2]. This awareness of eco-safety and increased environmental concern has led to the use of green and sustainable natural dyes as the needed trend in the textile industry [3].…”