Adsorption of dyes to cotton and inhibition by polymers

This paper addresses some key factors that control the transfer of dyes between garments during detergency. It is shown that adsorption of a series of substituted arylazo-2-naphthol dyes to cotton under simulated detergency conditions is influenced by the log P fragment value of the dye substituent; this suggests that hydrophobic interactions make an important contribution to the binding free energy. The comparative effectiveness of nonionic, zwitterionic and cationic polymers in inhibiting adsorption of dye to cotton was also investigated. Increase in polymer concentration reduces dye adsorption to cotton; increase in polymer molecular weight at constant polymer concentration also inhibits dye adsorption up to a molecular weight of ca. 20000, above which there is no further change. Anionic surfactants reduce the efficacy of polymers by displacing dyes from polymers. Surprisingly, certain dyes become relocated in polymer/surfactant complexes; binding is much more effective than in corresponding surfactant micelles.     

Detergents containing cationic hydroxyethyl cellulose: Benefits on dark garments leveraging a consumer relevant wash method

The industrial standard methods to evaluate color care of detergents leverage technical fabrics and use known dye standards from A.I.S.E. (International Association for Soaps, Detergents and Maintenance Products). This has some limitations: (1) it is not always following the latest fashion trends; (2) overall color fading of a garment is due to both dye bleeding out of the fabric as well as friction during the wash leading to fabric texture changes. The latter depends on parameters such as fabric type and surface area that could be better assessed on real garments. To overcome the above limitations, we have designed a new protocol considering the incidence of garment types, fiber and dye chemistry. Leveraging this protocol, we assessed the effect of the presence of a cationic hydroxyethyl cellulose in a commercial detergent formulation on dark fabrics/garments. Our results indicate that the commercial detergent formulation with cationic hydroxyethyl cellulose delivers dark/black color benefit.     

Study of Crystal Violet Hueing Dye Deposition on Fabrics During Home Laundry

The influence of hueing dye on the fabric b* value and CIE whiteness during home laundry was investigated using crystal violet dye to study the accumulation mechanism on fabric samples. Fabrics treated with the crystal violet dye had a lower b* value and a higher CIE whiteness. The dye accumulation was much higher on nylon or nylon/lycra blends than on cotton and polyester fabrics. The fabric surface charge and surface energy were also studied, and the dye-fiber interaction was investigated based on fiber and dye molecular structure. The study indicates: (1) the electrostatic adsorption is the main contributor to the deposition and accumulation of hueing dyes on fabrics; (2) fabric surface energy may play an important role in the dye-fiber interaction. The more hydrophobic the fiber surface, the less dye accumulates on the fabric during home laundry.     

Controlled foam laundry formulations

Heavy duty laundry systems are complex formulations containing a large number of ingredients. They can be formulated to produce a variety of foam profiles. This work has demonstrated that laundry detergent systems, which consist principally of biodegradable nonionic active components, may be formulated to exhibit low and moderate controlled foam profiles under typically American and European working conditions. In addition these formulations demonstrate excellent detergency properties when compared to currently distributed commercial brands. Presented at ISF-AOCS World Congress, Chicago, September 1970.     

Detergent enzymes: Developments during the last decade

The decade of the seventies saw dramatic changes in the formulation of heavy duty laundry detergents. The reduction in the STPP content in laundry product formulations was a notable example. During the early 1970s, heavy duty liquid laundry detergents were introduced and today represent an estimated 20% of the heavy duty laundry detergent market. A significant trend during this decade toward lower wash temperatures also appeared. These developments in home laundry products and washing trends have been followed by collateral developments in detergent enzyme technology. During the 1970s, a new generation of high alkaline, active detergent enzymes were developed. This new group of alkaline proteases were characterized by greater activity and stability under conditions of alkalinity between pH 10.5 to near 12, thus favoring phosphate-free detergent formulations. These enzymes also were found to exhibit superior stability in nonbuilt liquid laundry detergent systems. Safety considerations at the plant operation level have resulted in a continual improvement in the quality of coated and encapsulated detergent enzyme granulates. During the past 10 years, detergent enzymes have passed through three generations of physical forms, from the powders to prills to encapsulates. The decade of the 1980s offers exciting possibilities for enzymatic laundry products. The trend toward lower wash temperatures, caused initially by the popularity of synthetic fabrics, is being compounded by a radical reappraisal of household energy consumption patterns. In this new atmosphere of energy conservation, detergent enzymes will offer energy-saving options in an assortment of laundry products. Finally, as we start this decade of the 1980s, the spiralling cost of petrochemical feedstocks will cause us to rethink laundry product formulations and here again, detergent enzymes offer an important alternative for the future.     

Aspects of polymer use in detergents

Recent developments in polymer builders and specialty polymers (i.e., soil shield and soil release agents, dye transfer inhibitors) for detergents are reviewed. Attention focuses on polycarboxylates as detergent processing auxiliaries as well as detergent actives under low-temperature washing conditions.     

十二烷基二甲基苄基氯化铵在抗抑菌洗衣液中的应用

将十二烷基二甲基苄基氯化铵(1227)应用于洗衣液配方制备抗抑菌洗衣液,参照行业相关标准与市售抗抑菌洗衣液对比,全面考察了1227对产品感官和理化指标、去污力以及泡沫性能等的影响;重点考察了复配1227自制抗抑菌洗衣液的抗抑菌性能及其对人体皮肤的刺激性。结果表明,在去阴离子表面活性剂配方体系中,1227同其他表面活性剂的配伍性良好,产品的各项指标均能达到标准要求;复配1227自制抗抑菌洗衣液泡沫低,更易漂洗;复配1227质量分数为2%的自制抗抑菌洗衣液,其质量分数为1%的水溶液对大肠杆菌和金黄色葡萄球菌作用20 min的抗抑菌率均达到100%,具有较强的抗抑菌作用,远优于市售抗抑菌洗衣液对2菌种的抗抑菌效果,而且还具有较长时效的抗抑菌能力;复配1227质量分数为2%的自制抗抑菌洗衣液对人体皮肤无明显刺激作用。     

Soap-based detergent formulations: X. Nature of detergent deposits

The cumulative deposition of detergent residue on unsoiled cotton and polyester-cotton permanent press finish cloth was determined for a variety of detergent formulations after washing 25 consecutive times in 300 ppm hard water in a laboratory Tergotometer. Included in this study were: a phosphate-built laundry detergent, two carbonate-built detergents, tallow soap and various tallow soap formulations with anionic and amphoteric lime soap dispersing agents, and a glassy sodium silicate. Sample swatches washed with each formulation were analyzed for calcium, magnesium, and organic acid content. Fabric washed with the carbonate detergents showed the highest calcium and magnesium content, while those washed with the phosphate detergent and the soap-lime soap dispersant-builder formulations had the lowest. Fabric washed with soap alone had a much higher fatty acid residue than those washed with the other detergent formulations. However, the amount of organic acids left on the fabric after washing with a soap-lime soap dispersing agent formulation was no greater than that produced by phosphate- and carbonate-built detergents. The presence or absence of deposits also was verified visually with a scanning electron microscope. Each formulation also was tested for detergency by measuring the soil buildup in a multiwash procedure. Generally, the buildup of soil paralleled the deposit of detergent residue on the unsoiled cloths.     

Lipid distribution on cotton textiles in relation to washing with cellulase

Enzymes are used widely as effective additives to laundry detergents for improved detergency on soiled fabric. They have potential for cleaning of “dingy” soils in addition to the stain removal benefits. Cellulases contribute to the overall whiteness of cotton-containing textiles when worn and washed several times, meaning that their cleaning is not associated solely with the regions characterized by high amounts of fatty material, e.g., collars/cuffs. The focus of this research was to study further the performance of cellulases for whiteness maintenance of cotton textiles. Cotton garments soiled by multiple wearings and washed using a cellulase treatment were evaluated using scanning electron microscopy and X-ray microanalysis. Washing with cellulase significantly reduced residual soil concentrations at all morphological locations on the cotton fibers for each set of matched garments. The relative concentrations of residual soil on the fabrics agreed well with the color differences measured at 440 nm. Cellulase affected removal of oily soil from within the cotton fiber secondary wall, resulting in residual oil concentrations similar to those at morphological locations that were more accessible for detergency such as the fiber surface and crenulations. Since cellulase hydrolyzes cellulose, it was expected that the effect would be within the structure of the fiber, i.e., secondary wall. The cellulase effect on redeposition garments was similar to garments worn and washed. As with lipase, the enhanced removal of soil from the interior bulk structure of the cotton fiber with use of cellulase is unique, since most other detergent components have higher functionality at fabric, yarn, and fiber surfaces. We think that cellulase is functioning by hydrolyzing cellulose from the internal surfaces of fibrils within the secondary wall, opening up the pore structure for enhanced detergency and forming a new surface with each washing.     

The Application of a Nuclease Enzyme to Clean Stubborn Soils and Odors in Laundry

The inclusion of a nuclease, a new-to-laundry enzyme class in detergent formulations, reduces the concentration of recalcitrant soils on dirty clothing. Nucleases target extracellular DNA that, albeit present in minor quantities in soiled laundry items, disproportionately contributes to the accumulation of sebaceous soils and other compounds that affect the appearance of clothes. These lingering soils accumulate over multiple wear cycles and provoke a dingy appearance in clothing, characterized by dull colors, yellow staining, and an unpleasant malodor. The single and continued use of a nuclease in detergent formulations offers increased removal of these recalcitrant soils to produce less malodorous and visually preferred textiles. Furthermore, the nuclease is effective across different detergent forms, as well as in cotton short washing cycles, enabling improved cleaning in more sustainable laundry washing conditions.     

Desorption and transfer processes in different classes of dyes

We report an analytical approach to study dye desorption and transfer processes in aqueous environment. The study was conducted simulating standard laundry washes using two different donor textiles, a polyester textile dyed with Disperse Blue 79 and a cotton textile dyed with Reactive Red 239, and two acceptor textiles, undyed cotton and polyester, respectively. Dye bleeding/solubilization from a donor textile to the solution was investigated through UV–visible absorbance analysis, while the dye absorption onto acceptor textile was quantified by UV–visible reflectance analysis. Dye desorption and transfer processes were investigated in water and surfactant solutions at different concentrations. A desorption and transfer model for the two classes of dyes was hypothesized by performing kinetic experiments. The results show that both processes depend on the presence of surfactants for the disperse dye. Conversely, the presence of surfactants has little effect on the reactive dye. Finally, the presence of an acceptor polyester significantly increases the bleeding of the disperse dye, while the presence of an acceptor textiles less influences the total release of the reactive dye.     

Laundry detergents: an overview

Nowadays laundry detergents are becoming increasingly popular as they can be metered automatically into the washing machine, impart softness, antistaticness, resiliency to fabrics, mild to eyes and skins and shows good dispersibility in water. Because it is consumed when it is used, the sale of laundry detergent is a rather large business. There are many different kinds or brands of laundry detergent sold, many of them claiming some special qualities as selling points. A Laundry detergent composition is a formulated mixture of raw materials that can be classified into different types based on their properties and function in the final product. The different classes of raw materials are surfactants, builders, bleaching agents, enzymes, and minors which remove dirt, stain, and soil from surfaces or textiles gave them pleasant feel and odour. The physico-chemical properties of surfactants make them suitable for laundry purposes. Laundry detergent has traditionally been a powdered or granular solid, but the use of liquid laundry detergents has gradually increased over the years, and these days use of liquid detergent equals or even exceeds use of solid detergent. This review paper describes the history, composition, types, mechanism, consumption, environmental effects and consumption of laundry detergents.     

酶在现代洗净过程中的作用(英)(待续)

各种酶已经有效地帮助了现代家用和工业用洗涤剂的发展和改进。洗涤剂酶的主要类型（蛋白酶、脂肪酶、淀粉酶和纤维素酶）中的每一类为洗衣和自动洗碗机的应用提供了专门的好处。历史上,蛋白酶是一第一个在洗衣用洗洗剂中广泛的酶,酶除了提高洗争的水平外,还由于能够缩短洗涤时间、降低洗涤温度以及减少水的用量而节约能耗,从而对一半有利。当今,蛋白酶与脂肪酶和粉酶联合使用可以改善洗涤效果,尤其是在低 上的家用洗衣和工业     

Solid-State Chemistry of Cyanine-Type Dyes and the Effect of Two Novel Counterions on Their Crystal Properties

Organic dyes undergo a variety of solid-state chemical processes, including intra- and intermolecular reactions, gas-solid reactions, and polymorphic transformations. The properties of dye solids are markedly affected by this chemistry. This paper reviews solid state dye chemistry from the literature and reports in detail the chemistry of two novel cyanine dye salts whose properties are controlled by the nature of their counterions. In cyanine-oxonol salts, the oxonol counterion is a large planar dye which forms crystalline dye aggregates with cyanine ions. There is a multiplicity of polymorphic forms of these mixed dyes reflecting multiple favorable dye aggregate geometries. The cyanine-borate salts undergo intermolecular solid-state reactions. In either large single crystals or dispersions of the latter salts in polymer binders, alkyl transfer from the anion to the chromophore can be induced thermally or photochemically.     

水滑石焙烧产物对阴离子染料靛蓝胭脂红的吸附特性

碳酸根型水滑石焙烧产物对阴离子染料具有特异的吸附性能。该研究考察了两种具有不同镁铝摩尔比的镁铝复合氧化物对靛蓝胭脂红的吸附性能,并探讨了焙烧温度、投加量、初始染料浓度、溶液初始pH以及共存阴离子这几个因素的影响。结果表明经过500℃焙烧处理后的水滑石对染料的去除效果最好,去除率高达95%,平衡吸附量高达811.5 mg/g（1.74 mmol/g）;且吸附过程不受初始溶液pH和共存阴离子的影响。水滑石焙烧产物直接用于印染废水处理,脱色率达68%~84%。     

Behavior of cellulose grafted with poly(methyl methacrylate) and polyacrylonitrile toward some direct and reactive dyes

Viscose rayon fibers modified with polyacrylonitrile (PAN) and poly(methyl methacrylate) (PMMA) were dyed with some direct and reactive dyes. Exhaustion rate of the dye onto fibers was governed by the amount and nature of the polymer grafted. In general, the dye affinity for cellulose and dye exhaustion onto fibers decreased as the graft yield increased. Dye affinity for the PAN–cellulose graft copolymers was greater than that found with PMMA–cellulose graft copolymers. Except in a few cases, the tendency of cellulose graft copolymers of ca. 13% graft to accept direct dyes was more than that of the untreated cellulose, whereas the affinity of reactive dyes for cellulose graft copolymers of up to ca. 43% polymer was more than that of untreated cellulose. The dye fixation, based on the weight of cellulose component, increased as the graft yield increased. The dyeability of cellulose oxidized with ceric ammonium nitrate was also examined. Oxidation of cellulose prior to dyeing reduced the affinity of the dye for cellulose.     

木质素磺酸钠的改性及其作为洗涤助剂的研究

对木质素磺酸盐(LSs)的理化性能和其作为洗涤助剂的应用潜力进行了研究,讨论了其在洗涤配方中的作用及其机理。实验结果表明:木质素磺酸钠改性产物(GLS)比木质素磺酸钠(LS)具有更好的乳化力、起泡力和钙皂分散力;经过漂白处理后,LS的漂白产物(LSW)白度保持值为91.93%,而GLS的漂白产物(GLSW)白度保持值可达99.37%,基本对标准白布不造成沾污,消除了其对洗涤过程的负面影响;将LS及其改性产物应用于衣物洗涤剂配方中具有明显的增强皮脂去污力特性,为洗涤用品原料的选择提供了一个新的方向。     

Dyeing and finishing of lyocell union fabrics: an industrial study

Lyocell union fabrics, namely lyocell/silk and lyocell/polyester fabrics, were woven in different fabric constructions and dyed with reactive dyes, acid dyes and a disperse dye. The resulting dyed fabrics were given a resin finishing treatment and their wash fastness was measured. With appropriate dye selection and control of dyeing conditions, some bright solid shades and effective cross‐dyed shades were obtained. The dyed and finished fabrics had a smooth, lustrous handle, ideal for lightweight garments.     

The role of enzymes in modern detergency

Enzymes have effectively assisted the development and improvement of modern household and industrial detergents. The major classes of detergent enzymes—proteases, lipases, amylases, and cellulases—each provide specific benefits for application in laundry and automatic dishwashing. Historically, proteases were first to be used extensively in laundry detergents. In addition to raising the level of cleaning, they have also provided environmental benefits by reducing energy consumption through shorter washing times, lower washing temperatures, and reduced water consumption. Today proteases are joined by lipases and amylases in improving detergent efficacy especially for household laundering at lower temperatures and, in industrial cleaning operations, at lower pH levels. Cellulases contribute to overall fabric care by rejuvenating or maintaining the new appearance of washed garments. Enzymes are produced by fermentation technologies that utilize renewable resources.     

片状洗衣剂的技术特点

综述了洗衣用片状洗涤剂的技术发展情况，介绍了市售产品的基本形态和配方结构，分析对比了片状洗涤剂和浓缩粉在配方上的相同点和主要区别，特别对影响片状洗涤剂成型和溶解速度的主要因素，如表面活性剂和助剂原料，造粒方式和粒度大小、压力强度、黏合剂、水助溶剂及崩解剂种类等技术等特点进行了讨论。并片状洗涤剂的制备工艺进行了简介。