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The purpose of this paper is to prepare, analyse and measure the colour values of the lake pigments obtained from the reaction of Al3+, Fe2+ and Sn2+ metal salts with the natural dyes present in European buckthorn (Rhamnus cathartica L.).

A reversed‐phase high performance liquid chromatography (HPLC) with diode‐array detection method was utilised for the identification of buckthorn lake pigments. The extraction of dyes from the lake pigments was carried out with 37% hydrochloric acid/methanol/water (2:1:1; v/v/v) solution.

According to the results of the HPLC analysis of the lake pigments, it was determined that rhamnetin, kaempferol, and emodin were present in the acid hydrolysed plant extract and in the lake pigment that was precipitated by Sn(II), quercetin‐3‐arabinosid, rhamnetin, and emodin were present in the non‐hydrolysed plant extract, and kaempferol, rhamnetin, isorhamnetin, and emodin were found in the lake pigment that was precipitated by Al(III). Rhamnetin and emodin were present in the lake pigment that was precipitated by Fe(II).

In the present context for the preparation of buckthorn lake pigments, a simple and practical method is presented. In addition, the analysis of the lake pigments was performed by reversed phase HPLC (RP‐HPLC) with diode array detector (DAD).

The paper describes the preparation of lake pigments and their qualitative analysis. This method can be used to determine the origins of the dyestuffs used in historical art pieces.

The paper describes the development of methods for the analysis and the preparation of European buckthorn lake pigments.

The purpose of this paper is to characterise the electrokinetic properties of pigments supported on both unmodified and modified silica. The paper describes the preparation of hybrid pigments via adsorption of organic dyes on silica supports and determination of the zeta potential and electrophoretic mobility of the materials obtained.

The materials studied were hybrid pigments obtained as a result of adsorption of two basic dyes: C.I. Basic Red 1 and C.I. Basic Orange 14 and one acidic dye C.I. Mordant Red 3 from solutions of concentrations of 500, 2,000 and 3,000 mg/dm³ on the surface of both unmodified and modified silica supports. The agent used for modification of the silica surface was N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane.

The modification of the silica surface with aminosilane was found to change, significantly, the electrokinetic character of the inorganic support. This change was interpreted as being due to the ionisation of −NH₂ groups from the modifier molecule, which changes the surface charge. Electrokinetic curves of the pigment composites changed considerably as a function of the type and concentration of the organic dye adsorbed.

Only SiO2 supports (unmodified and aminosilane‐grafted) and C.I. Basic Red 1, C.I. Basic Orange 14 or C.I. Mordant Red 3 dyes adsorbed on its surface were evaluated. Other dyes could also be studied.

Measurements of the zeta potential were used to characterise the stability of colloidal dispersions of paints or dyes and to control the stability of paints on storage and their performance on painting and drying.

The paper demonstrates that the measurements of zeta potential permit determination of the optimum conditions for the use of a given pigment. The finding of the change of the zeta potential of a given pigment and so, also its application properties as a result of different functional groups in the dye or the modifying agent molecules.

The purpose of this paper is to develop an environmentally friendly dyeing process using brown pigment from chestnut shells (BPFCS). This material is obtained from foodstuff residues and can make a significant contribution to reusing a reproducible biomass resource, economizing petroleum, avoiding water pollution and protecting human health.

The brown pigment is extracted from the raw material and purified with solvents containing 30 and 100 per cent EtOH. It is then used to dye flax fabric in aqueous solution with added NaCl as a dye accelerator. The effects of dyeing conditions and fastness are investigated. The pigment, and the pristine and dyed fabrics are analysed by Fourier‐transform infrared spectroscopy (FT‐IR) and the fabric samples are observed using a scanning electron microscope (SEM). Fastness to washing, rubbing and light are also measured.

BPFCS show promising dyeability on cellulosic fibers. White flax fabric is successfully dyed with the pigment to a yellow‐brown colour. The base dyeing conditions are as follows: pigment concentration 16 g/l, NaCl concentration 10 g/l, liquor ratio 10:1, temperature 95°C, dyeing time 40 min. The dyed fabrics have lower fastness to washing and higher fastness to rubbing and light. A total of 4 per cent Al³⁺ or Fe²⁺ treatment of dyed fabric can improve fastness to washing, but decrease fastness to rubbing. The yellowish‐brown samples are transformed to brown or dark‐green after Al³⁺ or Fe²⁺ treatment, respectively. The pigment is a mixture with abundant hydroxyl groups.

The studies of dyeing conditions and fastness are carried out in detail as BPFCS used as a dye. However, a qualitative analysis of the pigment could not be performed due to the difficulty of separating the mixture. The BPFCS used in this paper can dye cellulosic fiber and can also be used to dye other fibers such as silk, wool and PET. Dyeing conditions for these other fibers need to be investigated.

BPFCS may play an important role in the dyeing industries because of its good dyeability, lack of toxicity and resistance to water, rubbing and light. The present work offers an environmentally friendly dye and a simple dyeing method.

At present, no report exists in the literature of work on dyeing flax fabric with BPFCS. This paper represents a preliminary study to determine the relationships of dyeing conditions to fastness and the role of mordant. BPFCS appears to be a new and practically useful natural dye.

Two types of amorphous silica namely, the precipitated silica and the pyrogenic silica, were studied. The surfaces of such silica were modified with silane coupling agents such as 3‐aminopropyltriethoxysilane, N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane and 3‐ureidopropyltrimethoxysilane. Pigments were obtained by the adsorption of organic dyes, C.I. Reactive Blue 19 and C.I. Acid Green 16, onto the modified silica surface. Structural properties of the modified silica and the pigments obtained were evaluated using scanning electron microscopy, zeta potential analysis and particle size measurement techniques. Moreover, colour of the pigments obtained was evaluated using the CIE L *a*b* colour space system. The specific surface area of the pigment obtained was estimated using the BET method.

Identification and characterization of organic pigments and dyes used in works of art and cultural heritage material such as prints, drawings, manuscripts, paintings, and textiles can provide important information for dating, authentication, and conservation treatment of these objects and studying art history in general. Applications of surface‐enhanced Raman scattering (SERS) for this purpose have recently attracted increasing attention of both academic scientists and museum researchers. This paper aims to review the latest development involving the emerging applications of SERS for the analysis of organic pigments and dyes used in works of art and cultural heritage material.

First, the importance of organic pigments and dyes in the studies of works of art and cultural heritage material and the challenges in their identification and characterization are briefly summarized. This is followed by a discussion on sampling considerations in the context of art and archaeology. Then the fundamental principle of SERS, SERS instrumentation and different types of SERS substrates are reviewed. Finally, selected examples of SERS applications to the identification of organic pigments and dyes, including the analysis of a couple of samples of artistic and archaeological interest, are presented and discussed.

The last few years have witnessed the emergence of SERS as a non‐destructive or micro‐destructive technique for the characterization of organic pigments and dyes found in artistic and archaeological objects. Spectroscopic and microscopic measurements using SERS have provided some novel information and answers to a wide variety of questions. However, SERS application to the field of art and archaeology is still in the fledging stage of development and requires closer collaboration between academic scientists and museum researchers. But the range of possible applications is broad. Future trends point to a strong need for the development of portable instruments for field applications.

By compiling this review, the authors hope to direct more attention toward SERS and bring together the expertise in the scientific, museum and art community to further explore the possibilities of SERS in rapid and direct identification of pigments and dyes under field conditions.

The purpose of this study is to improve the mechanical properties and reduce the stiffness/harshness of fabric associated with the pigment dyeing of textiles.

The fabric was pigment dyed with the addition of three different softeners and binders. The fabric was then analyzed to have improved textile properties by measuring tear strength, bending length, crocking and washing fastness tests.

The conventional route of pigment dyeing (without any softener) imparted poor mechanical and rubbing fastness. The softener-added recipe provided better mechanical, rubbing and washing fastness, and the stiffness values were oppressed as well.

Because of reduced stiffness, increased fastness and mechanical properties, the use of softener with pigment dyeing can improve the market values and satisfaction of the dyed fabrics. The finished product would also have better life and endurance. The process can be modified easily to have a better end-product with a negligible cost addition in industrial process, as softeners are cheap and used in low (10-20 g/l) in industrial settings without affecting the required shades.

This is the first report, to the best of the author’s knowledge, on the optimization of pigment dyeing of PC fabric with the addition of Helizarin and perapret softeners in dyeing bath.

The purpose of this paper is to colour aluminium pigment to the highest chroma using SiO₂ and organic silane with dichlorotriazine reactive dye and investigate its reaction mechanism, chemical stability and thermal properties to improve its applicability in surface coatings.

Aluminium pigment was encapsulated by the catalysed sol-gel method using SiO₂, followed by modification with γ-glycidoxypropyltrimethoxysilane (GPTMS). Purified reactive dye (1-Amino-4-[3-(4,6-dichlorotriazin-2-ylamino)-4-sulfophenylamino]anthraquinone-2-sulfonic acid (X-BR)) was covalently immobilized onto modified SiO₂ to obtain coloured aluminium pigment. The reaction mechanism, chemical stability and thermophysical properties were investigated by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscope, transmission electron microscope and thermogravimetric analyses (TGA).

The results showed that X-BR was covalently attached to modified Al/SiO₂ with maximum colour grafting of 95 per cent when the dosage of GPTMS and X-BR per weight of modified Al/SiO₂ was 25 and 15 per cent, respectively, at pH 8.5 and a temperature of 40°C. The coloured aluminium pigment had good chemical stability with excellent anti-migration properties in many solvents.

The organic silane used required a careful control of pH to ensure maximum colour grafting efficiency meanwhile other silanes with amine groups could also be used effectively with different kinds of colorants besides reactive dyes.

The method used is less cumbersome and provides a simple route to preparing coloured aluminium pigment.

The use of organic-inorganic SiO₂/γ- GPTMS with purified reactive dye to covalently colour aluminium pigment to the highest chroma is novel and will help advance the frontiers of knowledge on coloration of aluminium pigments.

The surface of pyrogenic silica was modified with silane coupling agent, such as N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane. Pigments were obtained by attaching different organic dyes, to a modified silica surface. The adsorption process was conducted in an aqueous suspension of the modified silica in the presence of the dye. In order to determine effect of silane on the dye adsorption process various amounts of the modifying compound was used. The microscopic properties, colour and particle size distribution were examined for the modified silicas and the obtained pigments.

Poly (acrylic) starch composites were prepared by polymerizing acrylic acid, acrylamide alone or in admixtures with maize starch using KMnO4/citric acid as redox initiation. The cooked composite pastes were used as partial substituent of kerosene oil emulsion in the pigment printing pastes for cotton fabric. Printing was carried out under a variety of conditions including neutralization of the free carboxylic groups of the polyacrylic acid component in the composite or AA/Aam mixtures, composite concentration, and the type of pigment dyes. The effect of storage on the efficiency of the printing paste was also examined. The printed samples were assessed for colour strength (K/S) overall fastness properties. Results obtained indicate that:

The study aims to test the color fastness of wool and linen fabrics dyed by simple immersion in ethanol dissolutions of fungal dyes.

Ethanol dissolutions of Talaromyces australis and Penicillium murcianum dyes were prepared to a concentration of 0.3% and used to dye wool and linen samples by immersion. Color fastness to washing, dry cleaning, wet and dry rubbing, perspiration and light, were tested according to AATCC standards.

Color fastness reached acceptable results at dry cleaning and wet and dry rubbing by crocking but did not performed well at laundering, perspiration and light exposure. Results indicate that ethanol dissolutions of tested dyes had better affinity for wool fabrics than linen, but the dyeing method requires further improvements to be considered attractive for full scale applications.

In this work sustainability of fabrics dyeing is improved by using natural pigments produced by filamentous fungi and a method to dye that requires no increment of temperature and mordants.