Cationic surfactants in laundry detergents and laundry aftertreatment aids

Cationic surfactants have a positively charged nitrogen atom and at least one hydrophobic, long-chain substituent in the molecule. Because of their fabric-softening and antistatic properties, they are used as active materials in fabric-softening agents. Suitable cationic surfactants are mostly quaternary ammonium salts, and to a lesser extent, imidazolinium salts with two long hydrophobic alkyl chains. Alkylated, partly ethoxylated polyamines, amine amides, ester amines and di-quaternary compounds also have recently been used or proposed. Fabric softeners generally are aqueous dispersions of distearyl dimethyl ammonium chloride or tallow alkylated imidazolinium derivatives in concentrations of 1–9%. Concentrated fabric softeners have recently been pushed into the market as double, triple or 10-fold concentrates. Fabric softeners used in the forms of acrosol sprays, pads or sheets, are not used in the washing machine but can be used in the laundry dryer. The combination of laundry detergent and fabric softener is a single product is impaired by anionic surfactants normally contained in laundry detergents because they react with the cationics to form neural salts. With the so-called soft detergents, one attempts to circumvent these difficulties by means of special formulations, e.g., with nonionics or by using definite physical-chemical mechanisms. They represent a compromise with regard to detergency performance and softening effect.     

Polycarboxylates in soda ash detergents

Calcium carbonate deposition on cotton fabric from soda ash-based detergents containing polycarboxylates is measured and related to polymer composition and molecular weight, under varying conditions of temperature, water hardness and detergent composition. Deposition effects on fabric are compared with threshold inhibition effects and calcium binding capacities of the polymers. Polyacrylic acids with molecular weights of 2000–5000 are most effective in preventing calcium carbonate deposition on fabric. A 1.5:1 acrylic acid:maleic acid copolymer is more effective than polyacrylic acid. Detergents with LAS left somewhat higher calcium carbonate deposits than detergents with a nonionic surfactant. Prevention of visible calcium carbonate precipitation in the absence of fabric (“threshold effects”) appears at polymer levels considerably lower than those necessary to prevent calcium carbonate deposition on fabric. Deposition on fabric can be prevented at levels of polymer much less than that necessary to bind most of the calcium ions, as determined by the calcium binding capacity. Presented at the AOCS meeting in New Orleans in May 1987.     

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.     

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.     

Consumer testing liquid syndets. II. Biodegradable formulations

The results of experiments investigating the interrelated effects of biologically degradable nonionic and anionic synthetic detergents in a light duty liquid detergent are presented. The formulations studied explore the performance of various biodegradable nonionic candidates in the presence of a fatty based alkylolamide foam stabilizer and biologically “soft” alkyl aryl sulfonate at two levels of nonionic concentration. The nonionic detergents evaluated are all polyoxyalkylated, including products of natural and synthetic origin. Products based on unsaturated and secondary alcohols are included. Consumer and laboratory test data show that biologically degradable detergents cannot be directly substituted in formulations without first testing their effect on the formulation itself. The data also show that small differences in molecular weight or in saturation of the materials being used can be reflected materially by technical differences in the finished product. These differences are manifested by analytical determination, by consumer panel evaluation using a duplicated balanced incomplete block design, and by standard dishwashing evaluation. The consumer panel data relate to dermatological properties, general performance and suds stability. It is obvious that the big switch to biologically degradable surface active agents is not as smooth a changeover as had been hoped, this being especially true for smaller producers of chemical specialties who do not have extensive facilities for formulation testing. These data do, however, indicate that with a careful experimental approach and judicious experimentation that formulations having a performance superior to their nonbiodegradable counterparts can be prepared. It is also stressed that judiciously designed consumer panel evaluations can yield data that is just as precise and valid as can be obtained through some of the more sophisticated testing procedures that require investment in equipment and in training of test panels. Presented at AOCS Meeting, New Orleans, April 1964.     

Moisture absorption capacity of polyamide 6,6 fabrics surface functionalised by chitosan-based hydrogel finishes

The present study aims at investigating the moisture absorption capacity of polyamide 6,6 fabrics when their surface is functionalised by chitosan-based hydrogels. For the finishing procedure, bulk hydrogels of chitosan (CS) with different contents of embedded thermosensitive microparticles of poly(N-isopropylacrylamide-co-acrylic acid) (PNIAA) were used. In practice, hydrogel incorporation into the fabric surface layer was achieved by crosslinking primary amine groups of chitosan with the end amine groups of polyamide, using the natural crosslinker genipin. Among other analytical techniques, Scanning Electron Microscopy (SEM) was used to characterize the surface morphology of both hydrogel and fabric samples, Differential Scanning Calorimetry (DSC) to determine the Lower Critical Solution Temperature (LCST) of PNIAA, and X-ray Photoelectron Spectroscopy (XPS) to analyse the fabric surface chemical composition. The fabric moisture contents were determined by weight measurements at different temperatures and relative humidity values (RH). Liquid porosimetry, water vapour transmission (WVT) and dynamic wetting measurements were also performed to assess the fabric pore volume distribution, permeability and wetting times, respectively. It was found that the moisture absorbed by the functionalised polyamide fabrics can be regulated at different conditions of temperature and relative humidity according to the PNIAA/CS ratio in the hydrogel. For example, at 40 °C (i.e. above the PNIAA LCST) and even at high RH (85%), the higher the PNIAA/CS ratio was in the incorporated hydrogel, the lower were the moisture contents of the functionalised fabrics, compared to the reference. In all cases, the presence of CS increased significantly the polyamide fabric wetting times.     

Ein Mikrowaschtest zur Bestimmung der Enzymwirkung

A Micro Wash Test for the Determination of Enzyme Performance A micro wasch test as well as two test fabrics stained with denatured proteins were developed. Test fabric A (blood-egg) responds only to proteases. When the latter are absent, no change in reflectance occurs either by agitation during washing, by detergents or by electrolytes at any pH below 11.5. Test fabric B (chocolate – milk) also responds only to proteases. In blank wash tests without enzyme no stain remova occurs. On the contrary, in blank tests this test fabric shows increased darkening with increasing pH. With these test fabrics the micro wash test has been used to evaluate the practical performance of very small quantities of enzymes isolated by gel chromatography or electrophoresis.     

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.     

Function of lipase in lipid soil removal as studied using fabrics with different chemical accessibility

Fatty stain removal is enhanced by the inclusion of lipase in washing compounds and leads to increased lipid removal from within the fibers. Cotton fabrics with varied morphology/chemistry were investigated to study the accessibility of soil in textiles to detergent and lipase. Three cotton fabrics (untreated, mercerized, and carboxymethylated cotton), differing in chemical accessibility, and Tencel^TM lyocell fabric, a microdenier manufactured cellulosic fiber, were subjected to three treatments—unwashed, washed with detergent, and washed with lipase—so as to understand further the effects of fiber morphology on lipase effectiveness. Both detergents and lipase removed more soil from the more chemically accessible and hydrophilic textiles. Lipase increased lipid removal for all fabrics and all morphological locations on the fiber, including fiber surfaces, interfiber capillaries, small capillaries, and the center of the yarn bundle. Lipase removed significant quantities of soil from the lumen in untreated and mercerized cotons; these fabrics showed the largest total increases in amount of lipid removed by lipase. When the fiber surfaces were smoother and the fiber structure was less open and not carboxymethylated, i.e., the mercerized cotton fabric, more lipase benefit was observed (72% of the residual soil left after washing with detergent was removed when lipase was added). The total soil removal from the mercerized cotton fabric by use of lipase was equal to that observed for the more open, hydrophilic carboxymethylated fabric and for the Tencel, which has no lumen or other morphological features of natural cotton such as crenulations. Lipase appeared to enhance lipid removal under conditions where removal by the detergent surfactant system was limited. Furthermore, we concluded that lipase acted to remove lipid soil from within the fibers by functioning at the interior surfaces of microfibrils and pores within the fiber structure at the lipid-water interface.     

荧光增白剂对洗衣液国标去污力及循环洗涤性能测试的影响

在标准洗衣液中添加不同种类和用量的荧光增白剂,根据GB/T 13174-2008进行国标去污力和循环洗涤性能测试。结果表明,若测试光源中包含紫外光,添加荧光增白剂的标准洗衣液的去污力和循环洗涤性能测试结果明显好于标准洗衣液,且荧光增白剂添加量增大,去污值和白度保持值增大;若测试光源中不包含紫外光,两者的去污力和循环洗涤性能测试结果并无明显差异。可见,荧光增白剂没有去污作用和抗污垢再沉积作用,但会显著提高国标去污力和循环洗涤性能的测试值。若要更加合理评价产品去污力,有必要按照GB/T 13174-2008进行洗涤,采用色度仪在不包含紫外光(滤除400 nm以下光源)的光源下测试,或者在含紫外光的正常光源下测试,但使用含有荧光增白剂的标准洗衣液作为参比。同时,GB/T 13174-2008未对白度计型号作出统一规定,使用不同规格的白度计测量添加荧光增白剂的洗涤剂产品时,将有不同的去污力和循环洗涤性能测试结果,建议尽快完善该标准。     

A realistic soil cloth and test procedure for detergent evaluation

The preparation of a uniformly soiled cloth for detergency studies is described. The soil, chosen for its realistic nature, consists of a colored clay as the particulate portion and triolein as the fatty or oily portion. The particulate portion of the soil is applied by tumbling the fabric in a horizontal axis washing machine containing a suspension of clay. The fatty portion is then applied by allowing the fabric to adsorb a known quantity of solvent-dissolved triolein with subsequent evaporation of the solvent. An evaluation test procedure for measuring the relative efficiencies of proprietary detergents is also described. Using this procedure, soil removal, soil redeposition and optical brightener effectiveness of a detergent are determined simultaneously. Detergents can thus be given a numerical rating according to their over-all performance. This rating is calculated from the equation: Overall Performance=Soil Removal−Soil Redeposition + Optical Brightener. Typical detergent evaluation data obtained with this soil cloth and test procedure are given, along with a statistical treatment of the data.     

The effect of washing and heat treatment on the surface characteristics of fluorocarbon resin-treated polyester

Polyester fabrics and films treated with two fluorocarbon resins were washed and heat treated. Water repellency, surface tension and ESCA measurements were carried out. Changes in the water repellency of the resin-treated polyester fabric caused by washing and heat treatment are related to modification of the chemical composition of the polyester surface.     

Sterols and Oxidized Sterols in Feed Ingredients Obtained from Chemical and Physical Refining Processes of Fats and Oils

The by-products obtained from conventional chemical and physical refining processes for edible fats and oils are important sources of valuable fatty components such as sterols, tocopherols, fatty acids, etc., and are also used as ingredients in animal feed formulations. Reports on sterol composition and content are limited, and the levels of oxidized sterols in these valuable by-products are unknown. This study analyzed by-product fractions from European refineries intended for use as ingredients in animal feeds for their content and composition of sterols and sterol oxidation products. The complex mixtures of sterol oxidation products were separated and quantified by multidimensional capillary columns, a medium polar DB-17MS and an apolar DB-5MS, in GC and GC–MS. Sterol content ranged from 0.l to 3.4 and 0.03 to 5.0 g/100 g in the by-product fractions collected from chemical and physical refining processes, respectively, while the corresponding ranges for sterol oxidation products were 0.02–17 and 0.02–1.5 mg/100 g.     

The effect of surfactant structure on the rate of oil solubilization into aqueous surfactant solutions

Reduced washing temperatures decrease the rate of the various processes in a laundry cleaning cycle. This implies that fast acting detergents are needed if acceptable washing performance is to be maintained within a realistic period of time. An important factor is the rate of oily soil removal which, among other things, is a function of the molecular structure of the surfactants used in the detergent. To support the selection of proper surfactants we have established relationships between chemical structure and rate of oil solubilization for a series of alkylarenesulfonates with various alkyl chain lengths, points of attachment of the phenyl group at the alkyl chain, and aromatic substitution patterns. It is shown that oil solubilization kinetics are very sensitive to the geometry of the surfactant structure: for a set of isomeric alkylarenesulfonates the rate of oil solubilization can be made to by more than an order of magnitude by changing the substitution pattern around the aromatic ring. The results offer a predictive tool for the design of molecules with the proper surface activity under a wide set of experimental conditions. Presented at the joint AOCS-Japan Oil Chemists’ Society meeting in Honolulu, Hawaii, in May 1986.     

阳离子改性棉织物活性染料染色性能

用自制的阳离子改性剂对棉织物进行改性处理,用浓度为6%(o.w.f.)的活性红3BS、活性黄3RS、活性黑KN-B三种染料分别对改性后的棉织物进行无盐染色。分别讨论了上染速率曲线、移染性能对上染性能的影响。得到的最优固色工艺为:碳酸钠用量为10 g/L~15 g/L,在60℃下固色20分钟~30分钟。改性棉织物的匀染性良好,耐水洗色牢度和耐摩擦色牢度与常规染色基本一致。     

Surface texturing of Mo–V–Te–Nb–O x selective oxidation catalysts

The paper concentrates on the study of Mo–V–Te–Nb oxide mixtures by electron microscopy combined with catalytic investigation of these materials in the partial oxidation of propane. Surface texturing of catalyst particles composed of two phases referred to in the literature as M1 and M2 is revealed by high-resolution transmission electron microscopy of high performing catalysts. The chemical composition of the catalyst surface is modified by treatment in water to obtain a significant increment in yield of acrylic acid. A chemical realization of the site isolation concept recurring on a supramolecular arrangement of catalyst and reactant rather than on atomic site isolation is suggested. A complex Mo–V–Te–Nb–O _x precursor phase carries nanoparticles made from a network of oxoclusters active as catalyst for the conversion of propane to acrylic acid. The designed synthesis of the multi-element oxide bulk and of the surface structure with a different composition than the precursor phase improved the performance by a factor of 4.     

Energetic-material combustion experiments on propellant formulations containing prilled ammonium dinitramide

Energetic material combustion experiments were performed on propellant formulations containing ammonium dinitramide prills. The overall performance of the formulation was found to be sensitive to the prill microstructure. The combustion experiments show that the performance of the composition could be further improved by “tailoring” the microstructural characteristics of the prills. These parameters are not revealed by strand burning-rate measurements, which represent an average or overall measurement and pick up on the localized rate variations as “noise,” averaging them out. Microstructural characterization (such as filming of the propellant combustion at the highest magnifications and examination of quenched samples) of propellant formulations may thus provide some of the complementary data to the standard propellant characterization measurements to reduce or eliminate measurement errors. Furthermore, with prilling the errors are reduced and the performance is improved. Translated fromFizika Goreniya i Vzryva, Vol. 36, No. 1, pp. 131–137, January–February, 2000. This work was supported by ONR.     

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     

双交联长链烷烃/有机硅防水剂的制备及其耐磨性能

以十八烯、甲基丙烯酸十八烷基酯、甲基丙烯酸丁酯、N-(羟甲基)丙烯酰胺、N,N-二甲基乙醇胺、丙烯酸和单乙烯基封端聚二甲基硅氧烷(Vi-PDMS)为单体制备了无氟防水剂。采用¹HNMR、凝胶渗透色谱仪、纳米粒度及电位分析仪、光学接触角仪对其进行了结构表征和性能测试。将其用于纯棉织物的整理，对整理织物的性能进行了测试。结果表明，当Vi-PDMS相对分子质量为2000、含量为单体总质量的3%、制备的无氟防水剂质量分数为10%时，整理织物的防水效果最佳。水在整理织物表面的接触角可达157°，滚动角为6°；整理织物在机械压力摩擦1000次、强酸强碱浸泡10 min、水洗5个周期后仍具有良好的疏水效果。整理前、后织物透气性变化不大，透气率分别为(697±54)和(720±35) mm/s，解决了传统涂层型防水织物疏水而不透气的问题。     

Establishment of a standardized detergency evaluation method

This paper describes a standardized laboratory procedure for determining the fabric soil-removal efficiency of heavy-duty detergents. A careful analysis of machines, standard soil fabrics, operating times, and water hardness had led to the standardization of technique. The precision of the method has been presented for tests carried out in hard and soft water on two anionic heavy-duty detergents at a concentration of 0.2%. Standard deviations of 0.74% for a water hardness of 50 p.p.m. and 1.03% for a water hardness of 135 or 300 p.p.m. have been obtained. Paper I in a series entitled: “Detergency Evaluations.” Presented at spring meeting, American Oil Chemists' Society, St. Louis, Mo., May 1–3, 1961.