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This research deals with a new kind of nanopigment, obtained from the combination of organic dyes and layered nanoclays, that the authors call nanoclay‐colorant pigment (NCP). Whilst they have already been employed in inks and coatings, to date these nanopigments have not been used as pigments for polymers. The existing lack of knowledge surrounding them must be redressed in order to bridge the gap between current academic studies and commercial exploitation. Therefore, the main purpose of this paper is to examine the hitherto unknown aspects of the NCP, which relate specifically to their applicability as a new type of colorant for polymers.

A blue NCP has been prepared at the laboratory according to the patented method of synthesis (patent WO0104216), using methylene blue and montmorillonite nanoclay. It has then been applied to a thermoplastic polymer (linear low‐density polyethylene – LLDPE) to obtain a coloured sample. Furthermore, samples with the same polymer but using conventional blue colorants have been prepared under the same processing conditions. The mechanical, thermal and colorimetric properties of these materials have been compared.

The thermal stability of the sample coloured with NCP is reduced to some extent, while the mechanical strength is slightly increased. Moreover, this sample has better colour performance than the conventionally pigmented samples.

In this paper, a blue NCP has been synthesised and successfully employed with polyethylene and the obtained sample shows better colour performance than polyethylene with conventional pigments.

This paper aims to study the physical and chemical characteristics of inkjet titanium dioxide inks for cotton fabric digital printing.

Different dispersing agents through the reaction of glycerol monooleate and toluene diisocyanate were prepared and then performed by using three different polyols (succinic anhydride-modified polyethylene glycol PEG 600, EO/PO Polyether Monoamine and p-chloro aniline Polyether Monoamine), to obtain three different dispersing agents for water-based titanium dioxide inkjet inks. The prepared dispersants were characterized using FTIR to monitor the reaction progress. Then the prepared dispersants were formulated in titanium dioxide inkjet inks formulation and characterized by particle size, dynamic surface tension, transmission electron microscopy, viscosity and zeta potential against commercial dispersants. Also, the study was extended to evaluate the printed polyester by using the prepared inks according to washing and crock fastness.

The obtained results showed that p-chloro aniline Polyether Monoamine (J) and succinic anhydride modified polyethylene glycol PEG 600 (H) dispersants provided optimum performance as compared to commercial standards especially, particle size distribution data while EO/PO Polyether Monoamine based on dispersant was against and then failed with the wettability and dispersion stability tests.

These ink formulations could be used for printing on cotton fabric by DTG technique of printing and can be used for other types of fabrics.

The newly prepared ink formulation for digital textile printing based on synthesized polyurethane prepolymers has the potential to be promising in this type of printing inks, to prevent clogging of nozzles on the printhead and to improve the print quality on the textile fiber.

Rheological Control Additives. Many additives to coatings affect the rheology of the composition so that application and storage properties are improved. A new rheological additive for emulsion polymers and water‐reducible resins has been described by Whitton and Masterson [Modern Paint & Coatings, November (1980) p. 33]. The authors point out that latex paints practically always require rheological additives if they are to have good application and stability properties. Without additives they are prone to dripping, sagging, and spattering as well as pigment settling, phase separation, and pigment flocculation. The most widely used rheological additives for waterborne coatings are cellulosic derivatives, and the authors estimate that 85 to 90% of latex trade sales coatings are thickened with additives such as hydroxyethylcellulose, methyl hydroxypropylcellulose, and methylcellulose. The disadvantages of these materials is that they are difficult to disperse which means that energy and time are consumed in grinding. Also, in automated pigment slurry systems the cellulosics require a large amount of water for dispersion. This limits flexibility in formulation. Also, the cellulosics can be attacked by enzymes although more expensive enzyme‐resistant forms are available.

Calcium stearate has many uses, including that of a flatting agent in paint, a lubricant, plasticizer and leveller for paper coatings, suspending agent in plastic and other mouldings, a tableting agent, a water repellant, and a cosmetic component, etc. Gives a complete breakdown and analysis of calcium stearate with a useful Appendix of journal and patent specification.

Gelation that can occur when copper or aluminium bronze powder is permitted to stand in nitrocellulose lacquer can be prevented by the addition of below one percent of lauric acid. Butyl acetyl ricinoleate will impart highgloss, plasticity, pliability to nitro‐cellulose lacquers and impart permanence, and improves the ageing properties and low temperature flexibility to the product. Acrylic coatings of improved gloss and pattern control have been provided by the addition of methyl hydroxystearate. When barium α‐sulphostearate is added to interior or exterior paints it can produce films of improved hardness. Methyl linoleate can be employed to retard the hardening of Japanese film lacquer. Compositions with good heat stability and good thixotropic properties and which are suitable for use as a base for paints have been evolved by reacting hydrogenated castor oil with toluene di‐isocyanate and emulsifiable and polyethylene wax. The use of aluminium stearate in paints at elevated temperatures can result in films of high opacity, good build, sag resistance, heavy pigmented tolerance and good sealing properties. Myristic acid‐based alkyd aryl ketones have been utilised to impart lustre to wooden surfaces, and stearic acid terminated polyamide/polyimide for coatings for electrical insulators of magnetic wire have been applied to give improved lustre. Diethylene glycol esters of dilinoleic acid can be used to produce non‐drip paints, as can ethylene diamine bis hydroxystearate, and glyceryl trihydroxystearate. Hydrogenated castor oil is useable in the making of thixotropic agents applicable to paints have been prepared from the material, plus oligomers of hydroxystearic acid/ethylenediamine/sebacic acid polymers. Ethyl linoleate and ethyl linoleate have been used as penetrants in anti‐corrosive paints based upon alkyd resins. Aluminium stearate can prevent excess penetration by paints of surfaces. Bis (hydroxymethyl) propanediol oleate has found use in alkyd resins derivative coatings with butylated melamine resins‐hardening materials to give pinhole resistant coatings. Butyl stearate is a good low temperature plasticiser for paints. Butyl acetyl ricinoleate imparts good plate release and cold crack resistance to leather lacquers, and provides good handle and excellent low temperature flexibility to coated fabrics on thick unsupported sheetings.

Adhesion promoters: Some oleochemicals can promote the adhesion of polymers to various surfaces, e.g. stearic acid can increase the adhesion of polyolef ins to metals and to the surfaces of other polymers. Erucamide is effective in the lamination of cellophane to polyethylene films, and alumina‐modified iron stearate has been found effective in aiding the adhesion of polyethylene to steel surfaces. The effect of oleamide on the adhesion of polyethylene to aluminium and to nylon 6 has been studied. Stearic acid had an adhesion promoting role in polyethylene/aluminium laminated packaging film. Barium stearate can effect the adhesiveness of poly(vinyl chloride).

The purpose of this paper is to prepare amphiphilic block copolymers polyethylene adipate-block-polyethylene glycol (PEA-b-PEG)s and study their performance as plasticizers in rotogravure ink formulations.

Series of amphiphilic block copolymers (PEA-b-PEG1), (PEA-b-PEG2), (PEA-b-PEG3), (PEA-b-PEG4) and (PEA-b-PEG5) were prepared by the reaction of adipic acid, ethylene glycol and polyethylene glycol of different molecular weights (300, 1,000, 2,000, 10,000 and 20,000 g/mol), respectively. Full characterization of the prepared copolymers was achieved using Fourier Transfer Infrared Spectroscopy (FTIR), 1H NMR, thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The performance of the prepared copolymers as plasticizers for neat nitrocellulose resin were studied in different formulations, namely, R1, R2, R3, R4 and R5 containing copolymers (PEA-b-PEG1), (PEA-b-PEG2), (PEA-b-PEG3), (PEA-b-PEG4) and (PEA-b-PEG5), respectively. In addition to formula R0 that contains acetyl tributyl citrate (ATBC) as a commercial plasticizer. The mechanical properties, thermal analysis (DSC, TGA) and optical properties of the prepared formulations films were investigated. Theses amphiphilic block copolymers were then applied as plasticizers in different rotogravure ink formulations (F1, F2, F3, F4 and F5) and compared with commercial rotogravure ink formula (F0). The color measurements and optical properties of all formulations were achieved.

It was found that the performance of the prepared copolymers as plasticizers in different formulations based on nitro cellulose resin gives better gloss, adhesion for R1 compared with the other samples and color strength for F1 compared with F0. Finally, all the samples gave excellent plasticizing effect.

The authors believe that type of these materials open the way for a new class of plasticizers that upon application or even degradation gives small ecofriendly molecules (adipic acid and or ethylene glycol moieties) taking into consideration the simplicity of the rout of the synthesis process.

The prepared ecofriendly (PEA-b-PEG)s could be successfully used as plasticizers instead of commercial plasticizer ATBC.

The research provides that the prepared (PEA-b-PEG)s with different molecular weights can act as plasticizers in rotogravure ink formulations, and their performance was acceptable and available.

Introduction Blistering of coatings under the influence of a temperature gradient was first observed some ten years ago. The process is induced when a heat flux passes through the coating to a colder wall. Elimination of the temperature gradient, e.g. through the use of pigments with a high degree of heat conductance, has been proposed as a remedy.

In Nigeria, roselle juice is quite popular among the populace presumably owing to its attractive colour, pleasant flavour and nutritional attributes. In the citrus industry, processing and packing material selection have significant effect on quality of juice product during storage. The effects of packaging materials, and storage temperature on colour and vitamin C retention of sobo juice extracted from local roselle plant were investigated.

Juice was extracted at three different temperatures: 20, 60 and 100°C for varying processing times of 5, 10, 15, 20 and 25 min respectively. Freshly extracted roselle juice was divided into three batches and independently hot‐filled into 500 mL pre‐sterilised glass, film packages and polyethylene terephthalate (PET) bottles allowing for minimum head space, capped, cooled and subsequently stored at 5 ± 1 and 28 ± 1°C respectively for eight weeks.

Optimum pigment extraction was obtained in 20 min with boiling water, while colour stabilisation of the extracted juice was affected with the use of food acidulants. Colour degradation on storage was pronounced in sweetened juice with greater colour loss in product held at ambient temperature. Colour and vitamin C retention with glass and plastic bottles provide higher retention of these quality attributes under cold and ambient storage condition than with the flexible polyethylene film.

Retention of colour and vitamin C was considerably higher in glass and PET bottles than in flexible film package. However, addition of table sugar or increasing storage temperature from 5 to 27°C affected colour stability.

This paper aims to critically review the isolation and chemistry of plant pigments.

A literature survey from 1974 to 2022 was carried out and studied thoroughly. The authors reviewed literature in various areas such as isolation methods and catalytic properties of pigments.

With vast growing research in the field of catalytic activities of various pigments like chlorophyll, anthocyanin and flavonoids, there is still scope for further research for the pigments such as Lycopene, carotenoids and xanthophyll as there has not been any significant work in this area.

Plant pigments may be used as an ecofriendly catalyst for chemical reactions.

One can get the direction of pigment research.

Plant pigments are natural and ecofriendly catalyst which can reduce the pollution.

This is an original work. This paper precisely depicts the advantages as well as disadvantages of the isolation techniques of pigments. This study also presents the chemistry of plant pigments.