Novel treatments of pigments with inorganic materials have tremendous industrial and commercial prospects. Specific treatment of pigment has a marked effect on its behavior during application. The treatment allows a broad modification of the surface characteristics of pigment particles which leads to improved functionalities. Surface modification of pigments is achieved via coating, polymerization with modifying reagent, treatment with derivatives or polymers, which alter either the optical, conductivity or dispersibility during processing and application. These and many other distinguishing factors that affect the characteristics of pigments such as the class, crystal structure, particle morphology, particle size, hiding power, pigment volume concentration, surface character, and surface treatment have been reviewed. Various organic pigments such as those from fungus and bacteria, and the various families of pigment types such as metallic pigment, light interference, and diffractive pigments which presents decorative quality such as leafing, nonleafing, pearlscent, and Fabry‐Perot effects on substrates have also been reviewed in addition to those from inorganic sources with emphasis on the structure and physiochemical modifications using metal and nonmetal Ions.

Purpose This study aims to evaluate the use of polyoxyethylene lauryl ether (PLE) as a dispersant in the preparation of novel pigment dispersion with enhanced dispersion ability, which can find application in the printing industry. Design/methodology/approach To obtain a good dispersion, PLE was used as a dispersant in pigments dispersion. The colloidal and rheological properties of the PLE-based dispersion, such as particle distribution, zeta potentials and apparent viscosity were evaluated. Findings The particle sizes of the pigment dispersions were within the range of 150 to 200 nm. The measurement of zeta potentials varied between −24 to −32 mV, revealing a strong surface charge interaction between pigments and PLE. Subsequently, its stability to high-speed centrifuge and freeze-thaw treatment was carefully investigated. To demonstrate the coverage of pigment particles by PLE, thermogravimetric analysis was carried out. Moreover, X-ray diffraction was used to disclose the combined impacts of PLE and ultrasonic power on the crystal structures of the pigments. Finally, the coloring performance and leveling properties of pigment dispersions on cotton substrates were evaluated by measuring their K/S values (color strength), rub and color fastness properties, which possessed good results. Research limitations/implications The dispersant used is incompatible with strong oxidizing agents and strong bases. More so, modification to improve its dispersion properties can be studied. Practical implications The use of PLE as a dispersant could be readily used in pigment dispersion processes and other suitable applications. PLE could also be used as a co-surfactant in synergy with other surfactants or dispersants in the dispersion process. Originality/value The use of PLE in pigment dispersion as well as investigating its coloring properties on cotton fabric is novel and can find various applications in the dying, printing and coating industry.

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An acid‐catalyzed esterification method was employed to synthesize five A‐B‐A‐type nonionic dimeric surfactants (XOP‐3, XOP‐4, XOP‐6, XOP‐9, and XOP‐10) comprising of octyl phenyl ether (OP‐10) and a homologous series of α, ω‐dicarboxylic acids (C3, C4, C6, C9, and C10) as the spacer molecules. The various surfactants produced were characterized based on Fourier transform infrared (FT‐IR) spectroscopy, mass spectra (MS), and 1H NMR spectra. The newly synthesized series of surfactants were used for the dispersion of Hostaperm Pink E (Pigment Red 122) in an ultrasonic disruptor. Based on the selected pigment, the interfacial, colloidal, and rheological properties of the pigment dispersion were examined. The dispersion performances and properties of the surfactants produced differed based on the number of carbon atoms in hydrocarbon chains of the various spacer molecules. Due to this, surfactants created with short to moderate hydrocarbon chain spacer molecules exhibited a better dispersion performance than that of surfactants created with long hydrocarbon chain spacer molecules. The calculated cross‐sectional area values of the various surfactants synthesized confirmed their differences in dispersion performance and properties.