Thickener In Printing Research Articles

Enzymatic synthesis of sodium alginate‐g‐poly (acrylic acid) grafting copolymers as a novel printing thickener

AbstractGrafting modification is a common method for improving the specific properties of polysaccharides. Herein, we synthesised sodium alginate‐g‐poly (acrylic acid) (NaAlg‐g‐PAA) as a novel printing thickener via catalysis of horseradish peroxidase and hydrogen peroxide in the presence of acetylacetone. The synthesised products were characterised by Fourier Transform–infrared spectroscopy and polar nuclear magnetic resonance spectroscopy, which confirmed that the PAA was successfully grafted onto the hydroxyl groups at carbon atoms (C2) of sodium alginate. The optimal grafting percentage and grafting efficiency reached 51% and 96%, respectively. Compared with native sodium alginate, the grafted copolymer NaAlg‐g‐PAA exhibited better thermal stability, rheological and printing properties. This work provides an efficient and promising approach for modifying polysaccharides like alginates and could be used as an alternative to conventional chemical modification.

New Approaches of utilization Aloe vera in Wet Processing of Textiles.

The application of aloe vera in textile processing is gaining worldwide detection as one of the hopeful approaches to pollution issues and cost reduction. Aloe vera gel possesses some biological activities and unique properties such as colorless, transparent, and viscosity which meet the using as a printing thickener, mordant, antimicrobial for different fabrics and dyes. Aloe vera is used in pre-treatment such as scouring, desizing, softening, and printing due to its succulent enzymatic and gummy characteristics. Aloe vera gel also contains a salty substance that allows its use in natural, eco-friendly dyeing. Aloe vera gel also is an alternative to synthetic antimicrobial agents. This state of art highlights the novel approaches of application of aloe vera in the textile coloration and industry covering both current types of research and pilot application.

Natural thickener in textile printing (A Mini Review)

The use of synthetic thickeners in the printing industry has several negative environmental consequences. As a result, in this study, we emphasized the use of various eco-friendly natural gums as thickeners to reduce the environmental impact. Fundamentally, printing is a type of colorings in which the colors are applied to specific areas of the fabric instead of the entire fabric. The resulting multicolored patterns have beautiful and artistic effects, increasing the value of the cloth above that of plain dyed cloth. The coloring matter is pasted with the help of a thickening agent to relegate it to the design area. Correct color, sharpness of mark, levelness, good hand, and efficient use of dye are all required for a successful print.

Sustainable antibacterial printing of cellulosic fabrics using an indigenous chitosan-based thickener with distinct natural dyes

PurposeChitosan is widely considered as a natural polymer and a diverse finish to impart antibacterial property and enhanced dye uptake of textiles. Herein, the authors have investigated the feasibility of using chitosan/starch blend as a thickener in screen printing of cellulosic fabrics with some natural dyes.Design/methodology/approachThe polymeric blend of chitosan/starch was prepared and used as a thickener for screen printing with three natural dye extracts, namely, Curcuma tinctoria (turmeric), Beta vulgaris (beet) roots and Lawsonia alba (henna) leaves on cellulosic fabrics like cotton and viscose. The viscosity and rheological properties of print paste as a fresh and after overnight shelving were examined. The influence of polymeric blends on cellulosic fabrics' print properties was inspected by determining their colorfastness, rubbing fastness, tensile strength and antibacterial activity.FindingsThe results depicted that chitosan/starch blend as printing thickener increased the shade depth with good wet and dry rubbing fastness for all the test natural dyes. The antibacterial activity of resultant printed cellulosic fabrics was found to be satisfactory against broad-spectrum bacterial strains.Practical implicationsThis study's outcome is the development of chitosan blend thickeners to print the cellulosic fabrics with indigenous natural dyes.Originality/valueThe authors found no previous report on the synthesis of chitosan-based antibacterial blend thickeners with three distinct natural dyes and their application in screen printing of native and regenerated cellulosic fabrics of cotton and viscose, respectively.

Technological Evaluation of Acrylic Acid /Cassia Saligna Gum Grafted products as Thickener in Textile Printing

Galactomannan gum extracted from Cassia Saligna seeds was subjected to graft copolymerization using acrylic acid. Thegraft copolymerization has been performed using potassium persulphate as initiator.The rheological property of the grafted product and it is utilization as a thickening agent in printing cotton fabrics with reactive dyes was thoroughly investigated. The rheological properties and theviscosity at various rates of shear were investigated. Furthermore, the results obtained indicate that grafted product gum could be used safely as a thickener in printing of cotton fabric, using silk screen printing instead of the commercial thickener of sodium alginate.

Extraction of Pectic Acid from Citrus Fruit Peels and its Application as Textile Printing Thickener

Extraction of Pectic Acid from Citrus Fruit Peels and its Application as Textile Printing Thickener

Recycling of terry towel (cellulosic) waste into carboxymethyl cellulose (CMC) for textile printing

Terry towels are widely preferred product in textiles and are generally made from pure cellulosic fibers. The huge quantity of terry towel, after use, is discarded as waste material. In the present investigation terry towel waste was converted to CMC and then utilized as a thickener in textile printing. The rheology of the thickener, which plays an important role in printing, was also studied in comparison with the standard CMC. The prints were analyzed by measuring color value (K/S), bending length and fastness to washing, crocking, and light. Results suggest that CMC obtained by waste recycling can substitute the sound CMC as a thickener in printing.

Rheology Study of Starch Extracted from Germinated Ragi and its Application in Textile Printing

Rheology Study of Starch Extracted from Germinated Ragi and its Application in Textile Printing Finger millet (Ragi) is a non-conventional carbohydrate rich source, which can be used as source of starch. Germinated ragi is generally discarded as a waste material and is used for non productive purposes. In the present investigation, starch extracted from germinated ragi has been compared with the starch from non-germinated ragi, as a thickener in textile printing. Extraction of starch was done by alkali steeping method. Analysis of both the starches was done by measuring swelling power, paste clarity, crystallinity and iodine binding. Printing of vat dyes on 100% cotton fabric was carried out using both the starches as thickener. The effect of solid contents of thickener and the shearing time on the viscosity of paste over a wide range of shear rates was studied for both germinated and non germinated ragi. The solid contents of the starch obtained from both germinated and sound grains were adjusted to have printable viscosity of the pastes. The prints were analyzed by measuring colour value (K/S and L*, a*, b* value), bending length, light fastness and fastness to washing and crocking. Results suggest that germinated ragi can be used partially in blends if not fully, as a thickener in printing.

Chitosan as a Thickener for Direct Printing of Natural Dye on Cotton Fabric

Development of chitosan as a thickener for direct printing of natural dye on cotton fabric was investigated. Chitosan was applied as a thickener at various concentrations and its effect on the print properties was determined in comparison with the typical printing thickener, sodium alginate. The results exhibited that chitosan affected the fabric properties by increasing fabric yellowness and stiffness. However, with increasing chitosan concentrations, the yellowness reduced only marginally. Direct printing on cotton fabric with 3% Natural Chestnut at varying chitosan concentrations showed that the optimum chitosan concentration for the printing was at 3%w/v, being equivalent to the viscosity of 17,800 mPa. The 3%w/v chitosan imparted the ultimate color yield, print outline sharpness and a minimal dye bleeding on the unprinted area of the fabric. Use of chitosan concentration higher than 3%w/v led to poor print properties on the fabric. The efficiency as a thickener of chitosan was found to be superior to sodium alginate. A high color yield and good color fastness properties on cotton fabric were rendered in the case of chitosan thickener at the same applied concentration with sodium alginate.

Enzymatic improvement of guar‐based thickener for better‐quality silk screen printing

Guar galactomannan (referred to as guar gum) is a versatile polysaccharide, obtained from the seeds of the shrub Cyamopsis tetragonolobus, which finds several applications in either its native or chemically modified form. For textile printing, guar gum can also be partially depolymerised in order to promote dye penetration, improve swelling in water and achieve the desired rheological properties. Guar gum is obtained from guar seeds by a thermo‐mechanical process that leaves ca. 3% of largely insoluble proteins in the gum, originating from the endosperms aleurone layer. When printing silk fabrics with acid or premetallised dyes, guar endogenous insoluble proteins bind tightly to anionic dyes, causing deposition of coloured aggregates on the fabric. This causes imperfections on the printed fabric in the form of tiny, but visible, ‘dots’, which lowers the quality of the final articles. In order to eliminate ‘dotting’, a novel printing thickener composed of depolymerised guar gum mixed with a bioengineered subtilisin protease has been developed. Upon solubilisation of the gum, and during preparation of the printing paste mixture, the protease hydrolyses guar gum insoluble proteins, generating soluble peptides that are washed off by the post‐printing treatments of the fabric. This enzymatic application prevents ‘dotting’ and significantly improves the quality of the silk print, without any measurable tensile strength loss of the fabric.

Application of germinated maize starch in textile printing

Germinated maize is generally discarded as a waste material. In the present investigation starch obtained from germinated maize has been compared with the starch from non-germinated maize, as a thickener in textile printing. Extraction of starch was done by alkali steeping method. Analysis of both the starches was done by measuring swelling power, paste clarity, particle size, crystallinity and iodine binding. Printing of vat dyes on 100% cotton fabric was carried out using both the starches. The prints were analysed by measuring colour value ( K/ S and L ∗, a ∗, b ∗ value), bending length and fastness to washing and crocking. Results suggest that germinated maize starch can substitute the non-germinated maize starch partially if not fully, as a thickener in printing.

Amaranthus paniculates (Rajgeera) starch as thickener in the printing of textiles

Maize starch is generally used in printing of Indigosol (solubilised Vat) and Vat dyes on cotton. Suitability of Amaranth starch to substitute conventional thickeners in printing of these dyes has been investigated. It was observed that Amaranth starch, which showed promising performance in printing of Indigosol and Vat dyes could be used in place of maize starch. Since this crop is underutilised, and also available at a cheaper rate, one could use the same for making thickeners for textile printing to substitute maize starch.

Fast Colour Printing

The development of fast‐ colour printing is traced from the discoveries of indanthrone and the formalde‐hyde‐sulphoxylates up to the present day. The relatively minor changes in machine printing technique since Bell's day are discussed, and screen printing is dealt with briefly.Some of the printer's hopes for the future are then considered. These include provision of an effective discharge agent for anthraquinonoid vats, and a discharge agent which does not attack the disulphide bonds of wool. The possible improvement of pigment printing colours is discussed, and the deficiencies of agera are touched on. Finally, the problem of the ideal printing thickener is dealt with in some detail.