Union Dyeing of Easy Care-Finished Wool/Viscose and Cotton/Wool Blends

Wool/viscose (60/40) and cotton/wool (70/30) blended fabrics have been easy-care finished in the presence of certain nitrogenous additives to produce readily dyeable cationic cellulose for competitive dyeing with wool dyes. The enhancement of easy care properties and improvement in post-dyeing of the finished fabrics were determined by the nature of substrate (wool/viscose > cotton/wool), type of catalyst (ammonium persulfate > ammonium sulfate > ammonium chloride > none), the kind of nitrogenous additive, as well as the type of polyethylene glycol (PEG-400 > PEG-200 > NONE). Using triethanolamine hydrochloride as a reactive/nitrogenous additive (30 g/L) in the finishing formulation as well as curing at 150°C/3 min make it possible to attain higher fabric resiliency along with better dye receptivity, regardless of the used anionic dye. However, the change in dyeing and fastness properties of obtained dyeing is governed by the nature of the anionic dye.     

Improving the antibacterial activity of cotton fabrics finished with triclosan by the use of 1,2,3,4‐butanetetracarboxylic acid and citric acid

For producing antibacterial textiles, the conventional finishing processes have high productivity and low processing costs, but textiles finished in these ways exhibit low durability against laundering. Therefore, cotton fabrics were bleached with hydrogen peroxide, finished with triclosan, and then treated with polycarboxylic acids such as 1,2,3,4‐butanetetracarboxylic acid (BTCA) and citric acid (CA) as crosslinking agents to provide durable antibacterial properties. The surface of fibers treated with BTCA had a greater crosslinked area, and the surfaces of fabrics treated with CA were exposed to greater amounts of deformation due to the mechanical and chemical influences after 50 launderings. The bleaching and finishing treatments did not dramatically affect the breaking strength. However, the polycarboxylic acid treatment (both BTCA and CA) alone showed reductions in the breaking strength when the acid concentration was increased. The polycarboxylic acids were fairly effective against both bacteria, even at lower concentrations, when they were applied to stand‐alone cotton fabrics, whereas the antibacterial activity decreased somewhat after the use of polycarboxylic acid and triclosan in the same recipes. Adding polycarboxylic acids to the antibacterial finishing recipes enhanced the durability after 50 launderings, and the durability of the recipes containing BTCA was much higher than that of the recipes containing CA. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Behavior of chemically modified cellulose towards dyeing. XIV. Behavior of cotton and crosslinked cottons before and after mercerization towards some reactive dyestuffs

Cotton fabric was crosslinked with DMDEU by applying the Form D-Process and Form W-Process. The cotton and crosslinked cotton were then treated with caustic soda solution of mercerizing strength. The ability of cotton and crosslinked cottons to dyeing with two reactive dyes, viz. Procion Blue MRB and Procion Red HB was examined. It was found that crosslinking reduces significantly the amenability of cotton to reactive dyes particularly when the Form D-Process was applied. Mercerization enhances dyeability of all substrates, but the enhancement was much greater in the case of noncrosslinked cotton. Based on dyeing and other properties such as tensile strength, elongation at break, and crease recovery, it was shown that crosslinking decreases considerably the affinity of cotton to caustic soda solution. It was further anticipated that different color designs with different patterns and properties can be conferred on a given cotton fabric by making use of local crosslinking and/or mercerizing followed by dyeing.     

Single-step dyeing and finishing treatment of cotton with 1,2,3,4-butanetetracarboxylic acid

A single-step dyeing and finishing (SDF) process was developed to eliminate dyeing problems associated with cotton crosslinked by polycarboxylic acid such as 1,2,3,4-butanetetracarboxylic acid (BTCA). This process consisted of several steps: (a) impregnation of the fabric by the bath containing BTCA, dye, and catalyst; (b) drying; and (c) curing at high temperature. Color strength (K/S) and dye fixation of cotton treated by the SDF process were excellent, especially with reactive dyes containing mono- or dichlorotriazinyl compounds and, in some cases, were higher than those of the sample dyed by a conventional batch process without finishing treatment. The presence of dye in the SDF process did not interfere with crosslinking of cotton. We believed that the reaction occurred between carboxyl groups of BTCA and s-triazinyl groups in reactive dyes in the presence of imidazole and other catalyst. FTIR, Raman, and X-ray fluorescence spectroscopies were used to confirm the mechanism of dye fixation. Elemental analysis also supported this mechanism. The SDF process can be an excellent way to dye fabric that also requires crosslinking treatment for smooth drying appearance. © 1994 John Wiley & Sons, Inc.     

Application of polycarboxylic acid sodium salt in the dyeing of cotton fabric with reactive dyes

In this study, the effects of polycarboxylic acid sodium salt on the dyeing of cotton with reactive dyes were evaluated by measuring and comparing the K/S values and dyeing fastnesses of the dyed cotton fabric samples. Results showed that the K/S value and dyeing fastness of cotton fabrics dyed with polycarboxylic acid sodium salt, substituting inorganic salts as exhausting agent were close to that of with sodium chloride when dip‐dyeing process was used. While, in pad‐dry dyeing, the K/S value of cotton fabric samples dyed with polyacid salts as exhausting agent was higher than that of with sodium sulfate, and the dyeing fastnesses of these samples were nearly the same. The dyeing mechanism of cotton fabric with reactive dye, using polycarboxylic acid sodium salt as exhausting agent was analyzed. The dyeing exhausting mechanism of reactive dye seems different when the inorganic salt and polycarboxylic acid sodium salt were used as exhausting agent in the dyeing of cotton fabric with reactive dye. The polycarboxylic acid sodium salt, as weak electrolyte, increased the dye‐uptake of reactive dye on cotton fabric not only by screening negative charges on cotton surface, but also by the effect of salting‐out or hydrophobic combination. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Cetylpyridinium chloride cationic finishing improves the dyeing and antibacterial properties of madder dyed cotton

In this work, after cationic pretreatment of cotton fabric with cetylpyridinium chloride (CPC), the compound of citric acid (CA) and succinic acid (SUA) were used as crosslinking agents to dye cotton fabrics with natural madder dye to improve the dyeing and antibacterial properties and realise the multifunctional finishing of cotton fabric. The effects of mordant dyeing, CA + SUA crosslinked dyeing, and CPC/CA + SUA crosslinked dyeing on the microstructure and properties of cotton fabrics were compared. The dyeing by the three processes occurred primarily in the amorphous zone of the fibres, and all kept the original crystalline form of the cotton. CA + SUA crosslinked dyeing and CPC/CA + SUA crosslinked dyeing increased the thermal stability of the cotton fabric. CPC/CA + SUA crosslinked dyed cotton obtained excellent dyeing results with the colour depth value (K/S) of 12.3 and rubbing fastness and washing fastness of levels 4–5, and the levelness and dye permeability were acceptable. Furthermore, the antibacterial rate against Escherichia coli and Staphylococcus aureus reached 99.99%, and the ultraviolet protection factor (UPF) reached 50+. Moreover, the wrinkle recovery angle (WRA) increased by 55% compared with raw cotton. This showed that CPC/CA + SUA crosslinked dyed cotton had excellent antibacterial, anti-ultraviolet, and anti-wrinkle performances.     

棉纤维化学改性与染色性能研究

棉纤维通过化学改性和交联作用，增加棉纤维与活性染料的反应能力，达到增深和提高染色牢度的目的。棉纤维染色中不仅需要进一步提高活性染料的固色率、改善其各项性能，而且要重视纤维活化改性和交联染色法的研究。     

Co-application of hydroxyalkyl dyes and polyphosphonic acids to cotton to achieve dye—fibre covalent bonding

The dyeing of cotton to a high standard of wet-fastness with hydroxyalkyl dyes and a polyphosphonatecrosslinker system has been investigated. Dyes containing hydroxyalkyl groups were prepared, by the reaction of commercial reactive dyes with ethanolamine, and applied to cotton fabric in the presence of polyphosphonic acid crosslinking agents using cyanamide as a catalyst. The application was carried out using a pad-thermosol method. The effects of cyanamide concentration, the nature of the crosslinker and the type of hydroxyalkyl dye were studied in detail. It was concluded that multifunctional polyphosphonates are capable of producing dyeings on cellulosic fibres exhibiting a high degree of covalent bonding (fixation). The efficiency of dye fixation at ca. 2% pure dye (owf), obtained from this method, was greater than 90%.     

Proper finishing treatments for sun‐protective cotton‐containing fabrics

To enhance both the performance and ultraviolet‐protection properties of cotton‐containing fabrics, attempts have been made to use poly(carboxylic acid)s as non‐formaldehyde durable‐press finishing agents alone or in combination with certain additives followed by posttreatment with metal salt solutions. Furthermore, simultaneous dyeing and resin finishing in the presence of triethanolamine hydrochloride (TEA · HCl) or citric acid (CA) as a reactive additive along with different anionic or cationic dyestuffs have been examined. The results reveal that the ester crosslinking of cotton‐containing fabrics in the absence or presence of chitosan (5 g/L), β‐cyclodextrin (20 g/L), or choline chloride (20 g/L) as an additive results in an improvement in the fabric resiliency as well as the ultraviolet‐protection properties. The extent of the improvement is determined by the type of poly(carboxylic acid), type of additive, type of substrate (i.e., cotton or cotton/polyester blend), and pretreatment history (i.e., grey, bleached, or bleached and mercerized). The posttreatment of easy‐care finished fabric samples with a copper acetate solution (5 g/L) results in a dramatic improvement in the ultraviolet‐protection factor, especially with bleached cotton, grey cotton/polyester blend, and bleached cotton/polyester fabric samples, regardless of the additive. Simultaneous dyeing and resin finishing with Reactive Black 5 and Direct Violet 31, in the presence of TEA · HCL as a reactive additive, or with Basilene Red PB, in the presence of CA as a reactive additive, result in a sharp increase in both the depth of shade and the ultraviolet‐protection values, regardless of the substrate. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1024–1032, 2005     

Durable antimicrobial treatment of cotton fabrics using N‐(2‐hydroxy)propyl‐3‐trimethylammonium chitosan chloride and polycarboxylic acids

N‐(2‐hydroxy)propyl‐3‐trimethylammonium chitosan chloride (HTCC), a water‐soluble chitosan quaternary ammonium derivative, was used as an antimicrobial agent for cotton fabrics. HTCC has a lower minimum inhibition concentration (MIC) against Staphylococcus aureus, Klebsiella pneumoniae, and Escherichia coli compared to that of chitosan; however, the imparted antimicrobial activity is lost on laundering. Thus crosslinking agents were utilized to obtain a durable antimicrobial treatment by immobilizing HTCC. Several crosslinkers such as dimethyloldihydroxyethylene urea (DMDHEU), butanetetracarboxylic acid (BTCA), and citric acid (CA) were used with HTCC to improve the laundering durability of HTCC treatment by covalent bond formation between the crosslinker, HTCC and cellulose. The polycarboxylic acid treatment was superior to the DMDHEU treatment in terms of prolonged antimicrobial activity of the treated cotton after successive laundering. Also, the cotton treated with HTCC and BTCA showed improved durable press properties without excessive deterioration in mechanical strength or whiteness when compared to the citric acid treatment. With the addition of only 0.1% HTCC to BTCA solutions, the treated fabrics showed durable antimicrobial activity up to 20 laundering cycles. The wrinkle recovery angle and strength retention of the treated fabrics were not adversely affected with the addition of HTCC. Therefore, BTCA can be used with HTCC in one bath to impart durability of antimicrobial activity along with durable press properties to cotton fabric. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1567–1572, 2003     

Dyeing properties of novel electrolyte‐free reactive dyes on cotton fibre

A series of electrolyte‐free reactive dyes containing two quaternary ammonium salt groups as soluble moieties and one epoxy structure as the reactive group have been synthesised. The structures of the synthesised dyes were confirmed by Fourier Transform–infrared, proton nuclear magnetic resonance and elemental analysis, and their dyeing properties on cotton were studied using an electrolyte‐free dyeing process. The results indicate that electrolyte‐free reactive dyes with these structures give a high exhaustion rate, a high fixation rate and good build‐up properties on cotton. Fastness properties were, in general, also very good. The optimal dyeing process of these electrolyte‐free dyes for cotton fibre was 60 °C with 20 g/l sodium carbonate.     

棉纤维阳离子化与活性染料无盐染色

本文系统综述了棉纤维阳离子化试剂的发展，阳离子化试剂主要有6种类型：环氧类含氮化合物、一氟均三嗪型季铵盐化合物、氮杂环丁烷阳离子化合物、N-羟甲基丙烯酰胺和阳离子丙烯基共聚物、羟烷基铵盐化合物以及生物质阳离子化试剂。对各类阳离子化试剂在活性染料染色中的优缺点进行了分析：生物质阳离子化试剂的研究已逐步显现出优势．在棉纤维阳离子化同时赋与纤维其它功能性，出成为阳离子化试刺研发中的另一个重点有30篇参考文献。     

Influence of additives on the formation of unsaturated PCAs produced during durable-press curing with citric acid

To impart durable-press properties to cellulosic material, the fabrics have been treated with a finishing bath containing a polycarboxylic acid in combination with an appropriate catalyst. When citric acid (CA) was applied as crosslinking agent discoloration of the fabric was observed. Special additives were included into the formulation to improve the whiteness index. Isocratic HPLC was used to identify and quantify the unsaturated polycarboxylic acids that are produced during the curing process of CA-treated cotton fabrics. The influence of different catalysts (sodium hypophosphite, sodium dihydrogen phosphate, disodium hydrogen phosphate, tetrasodium pyrophosphate, trisodium phosphate) and of various types of additives, such as triethanol amine (TEA), W,/V,bis(hydroxy-ethyljglycine (BICINE), boric acid and polyethylene glycol 200 (PEG 200), on the content of CA and the amount of unsaturated PCAs in the wash liquor and on the fabric has been investigated. A significant reduction of the unsaturated polycarboxylic acids was observed when an additive was incorporated into the pad bath.     

IR spectroscopy study of cyclic anhydride as intermediate for ester crosslinking of cotton cellulose by polycarboxylic acids. V. Comparison of 1,2,4-butanetricarboxylic acid and 1,2,3-propanetricarboxylic acid

In recent years extensive efforts have been made to use multifunctional carboxylic acids as formaldehyde-free crosslinking agents for cotton to replace the traditional formaldehyde-based N-methylol reagents. In our previous research we found that a polycarboxylic acid esterifies cellulose through the formation of a five-membered cyclic anhydride intermediate by dehydration of two adjacent carboxyl groups. In this research we used Fourier transform IR (FTIR) spectroscopy to study the formation of cyclic anhydride intermediates and crosslinking of cotton by 1,2,4-butanetricarboxylic acid (BTA) and 1,2,3-propanetricarboxylic acid (PCA). BTA and PCA form five-membered cyclic anhydrides in the same temperature range. Both acids form the anhydrides at lower temperatures when a catalyst is present. When an acid molecule is bonded to cotton through an ester linkage, only PCA is able to form a second anhydride intermediate. We found that PCA is a more effective crosslinking agent, and it imparts higher levels of wrinkle resistance to the cotton fabric than BTA. Therefore, the formation of a five-membered cyclic anhydride by a polycarboxylic acid accelerates the esterification of cotton by the acid. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2142–2150, 2001     

高取代度阳离子淀粉改性棉纤维用于活性染料无盐染色的研究

本文以取代度为0.6的高取代度季铵型阳离子淀粉为阳离子化试剂,对棉纤维进行阳离子化改性,用于活性染料无盐染色.通过改性棉纤维表面Zeta电位变化和染料等温吸附曲线对无盐染色促染机理进行研究,对有盐染色和无盐染色中的染料色光、色牢度和染色纤维折皱回复性和强度性能进行比较,从而对高取代度季铵型阳离子淀粉的应用性能进行综合评...     

Pretreatment of cotton fabrics with polyamino carboxylic acids for salt‐free dyeing of cotton with reactive dyes

In this study, polyamino carboxylic acids have been used to improve the dyeability of cotton in a salt‐free reactive dyeing process. These polyamino carboxylic acids were prepared by partial carboxylation of polyvinylamine. Cotton fabric was pretreated with polyamino carboxylic acids and dyed with reactive dyes. The colour strengths of the dyed fabrics were evaluated by measuring the K/S values. The fastness properties (washing, rubbing and light fastness) of the dyed cotton fabrics were also measured. The pretreatment of cotton with polyamino carboxylic acids creates positive charges on the fabric surface. In this way, salt‐free reactive dyeing of cotton or dyeing with only a small amount of electrolyte is possible.     

Durable press finishing of cotton with polycarboxylic acids. II. Ester crosslinking of cotton with dithiosuccinic acid derivative of S-triazine

The preparation of an alternative polycarboxylic acid to replace the most promising but expensive crosslinking reagent butanetetracarboxylic acid (BTCA) was reported in Part I.¹ Part II studies the efficiency of the crosslinking of cotton with the dithiosuccinic acid derivative of s-triazine (HDTST). Diffuse Reflectance infrared (DR FTIR) spectroscopy in combination with wrinkle recovery angle measurements (WRA) were used to analyse the efficiency of cotton cellulose crosslinking. Energy Dispersive X-ray analysis (EDX) of the polycarboxylic acid-finished cotton fabric was performed to study sulphur distribution. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 171–177, 1997     

Pore and crosslinking structures of cotton cellulose crosslinked with DMDHEU‐maleic acid

Two dicarboxylic acids (maleic acid and tartaric acid) were used in conjunction with DMDHEU as the crosslinking agents to treat cotton fabric samples. The treated fabrics then were dyed with direct red 81. The results show that the values of the dye absorption, equilibrium absorption, rate constants, and the pore index of structural diffusion resistance constant for the various crosslinking agents are ranked as DMDHEU‐tartaric acid > DMDHEU‐maleic acid > DMDHEU alone at the same dyeing temperature. The activation energies for the three crosslinked fabrics are in the rank of DMDHEU > DMDHEU‐maleic acid > DMDHEU‐tartaric acid. The CL length values for the various crosslinking agent systems are in the series of DMDHEU‐tartaric acid > DMDHEU‐maleic acid > DMDHEU alone for a given number of CL/AGU. The values of the pore index of structural diffusion resistance constant and dyeing rate constant are increased with the increase of CL length. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 143–148, 2005     

Effect of mercerisation and crosslinking on the dyeing properties of ramie fabric

The dyeing of ramie fabrics crosslinked with 1,2,3,4-butanetetracarboxylic acid has been studied using a typical direct dye CI Direct Red 81. Adsorption time curves from finite baths of untreated ramie, tension-mercerised ramie, slack-mercerised ramie and cotton fabrics have been compared. It has been found that mercerisation improved the equilibrium adsorption and dyeing rate, while it reduced the maximum dye adsorption and equilibrium constant on ramie fabric. Crosslinking with butanetetracarboxylic acid decreased most of these parameters related to the dyeing profile, although the activation energy of dyeing was increased. A pore model approach has been used to explain the changes in dyeing properties arising from the crosslinking of ramie using butanetetracarboxylic acid.     

Infrared spectroscopic studies of the nonformaldehyde durable press finishing of cotton fabrics by use of polycarboxylic acids

A number of polycarboxylic acids have been used successfully as new nonformaldehyde cross-linking agents for cotton fabrics. In our previous research, Fourier transform infrared photoacoustic spectroscopy (FTIR/PAS) demonstrated the ability for characterizing ester cross-linkages in the finished cotton fabrics. In this research, the effects of different acid concentrations, different catalyst concentrations, different curing temperatures, and different curing times on the ester cross-linking of the cotton fabrics were determined by FTIR/PAS. The infrared spectroscopic data were also correlated to durable press (DP) ratings. FTIR appears to be useful for evaluating the effectiveness of polycarboxylic acids as cross-linking agents for cotton fabrics. FTIR definitely complements the existing methods for evaluating finished textile fabrics.