纤维织物上靛蓝浓度的测定

介绍了一种快速精确测定染色纱线和织物上靛蓝浓度的分光光度法，靛蓝染色纱线被浓硫酸溶解后，对得到的溶液进行分光光度分析，该方法的精确度可用常规的吡啶萃取法进行验证，是一种既快速又安全的方法。     

天然抗菌植物靛蓝在牛仔纱线染色中的应用

对植物靛蓝连续染色牛仔纱线进行了实验研究。染色纱线织成的面料耐水洗色牢度、耐汗渍色牢度、耐干摩擦色牢度及耐唾液色牢度都在4级及以上,该面料及其经多种洗水风格处理后的服装对金黄色葡萄球菌的抑菌率在80%以上,对大肠杆菌的抑菌率在78%以上,具有很好的抗菌性能。     

靛蓝染料的生产及应用技术进展

简要介绍了植物靛蓝的制备方法,分析了化学与生物靛蓝染料的主要生产工艺及其特点,论述了用于靛蓝染料染色的还原方法及对染色效果的影响,对超细靛蓝再到液体靛蓝的性能进行了详细的分析。根据目前国内外的研究现状的分析,对靛蓝染料今后的发展做出了展望。     

靛蓝提取物中靛蓝和靛玉红的分析方法比较

以靛膏为原料,采用盐酸酸化、葡萄糖还原和乙酸乙酯提取3种工艺制备靛蓝酸化物、靛蓝还原物和乙酸乙酯提取物。建立高效液相色谱(HPLC)法、紫外可见分光光度(UV)法和双波长紫外分光光度(dW-UV)法,分析3种靛蓝提取物中靛蓝和靛玉红的含量,并以Kolmogorov-Smirnov检验、Bland-Altman偏差图比较和Spearman检验确定3种样品各自最佳分析方法。结果表明：所建立的HPLC法、UV法和dW-UV法简单、准确、灵敏度高、稳定性好和重复性好。3种靛蓝提取物成分含量检测方法均遵从正态分布,两两测定值存在显著差异。UV法更适于分析靛蓝酸化物、靛蓝还原物中靛蓝含量;HPLC法更适于乙酸乙酯提取物中靛蓝、靛玉红含量分析。     

可湿粉靛蓝染色试验

近年来,我国靛蓝坚固呢生产发展很快,靛蓝染料成为热门货。从我厂几年来的生产实践看,靛蓝染色存在着成本高、色牢度低的问题(我厂使用的染料是靛蓝原粉),需要对染色工艺进行不断的研究和改进。最近,我们进行了可湿粉靛蓝染色试验,取得了较好效果,现报告如下:一、可湿粉靛蓝染料简介我们使用的可湿粉靛蓝WP,是由沈阳化工研究院研制、河北武强化工总厂批量生产的。这种可湿粉靛蓝染料保持了原有靛蓝染料的化学结构,某些指标甚至好于国外同类产品。它具有较好的扩散性、溶解性和渗透性,     

利用糖精副产合成靛蓝的研究

一、前言靛蓝是一种棉用染料,广泛用于棉织物的染色,特别是用于牛仔裤的染色。它具有良好的耐晒、耐洗牢度。该产品除用做染料外,也可用于纸张染色、有机颜料和食品染料。合成靛蓝的方法很多,工业生产主要采用苯胺法和苯酐法。我国目前的生产装置都是采用苯胺法,苯酐法尚无厂家生产。据报导,日本、南朝鲜、台湾及西欧有些厂家采用苯酐法。苯酐法合成靛蓝是以苯酐为原料,先制成邻氨基苯甲酸,再经多步反应制成靛蓝。邻氨     

新产品—靛蓝增深剂HY-2的使用价值

靛蓝染料在国内多用于牛仔布的经纱浸染上,生产量日益增高。由于靛蓝对棉纤维的亲和力低下,需要反复多次浸染氧化,才能达到染色的目的,这样造成染厂的染色设备增加,厂房占地面积加大,产品成本上升。沈阳化工研究院新研制成一种靛蓝增深剂     

化学试剂乙酸铵的硝酸盐测定方法改进

在GB/T 1292-2008化学试剂乙酸铵标准中,用马钱子碱比色法测定硝酸盐,但马钱子碱是剧毒品,在购买、使用和保管上有诸多限制。本文以靛蓝二磺酸钠(靛蓝胭脂红)分光光度法代替马钱子碱比色法测定化学试剂乙酸铵中的硝酸盐,最佳线性范围0~50μg(以NO_3计),相对标准偏差优于10%,平均加标回收率可达95%,且两种方法检测结果一致。靛蓝二磺酸钠(靛蓝胭脂红)分光光度法避免使用剧毒品,方法准确、简便且实用。     

实用染色的若干应用技术(十九)

问:溴靛蓝可否取代靛蓝染纯棉织物? 答:溴靛蓝2B,俗称溴靛粉(c.I.还原蓝5),是靛蓝的衍生物,即4溴化靛蓝,化学结构式为: 溴靛蓝用途广泛,对纤维素纤维和蛋白质纤维都具有优良的亲和力和匀染性.溴靛蓝2B的各项色牢度(表1)均较理想,有亚士林(anthrene)之称.它的碱性隐色体呈姜黄色,酸性隐色体呈淡黄色.实践证明,溴靛蓝染色织物比靛蓝亮艳,但这两种染料都受到颜色的局限性,即只宜染深浅不同的蓝色,如水蓝、毛蓝、藏蓝和深藏蓝等.溴靛蓝的染色工艺比较简便,能一次染成.     

涤/棉混纺的反向染色

反向染色是指在染涤/棉混纺织物或纱线时,先用活性染料染棉,后用分散染料染涤纶,与常规染色正好相反的一种染色方法。用此法染色可省去活性染料染色的中和及后处理,且利用后来涤纶高温染色作为纤维素纤维最佳的后处理,因而是一种既经济又可靠的染色法。赫斯特公司在开发反向染色中,以Sam-aron分散染料和Remazol活性染料染涤/棉混纺织物和纱线,其方法如下:     

Studies on indigo dyeing and diffusion by the film roll method

The influence of reducing agent, indigo concentration and dyebath pH on indigo dyeing and diffusion was studied for the film roll method. An almost linear relationship between the indigo concentrations in the dyed film and in the dyebath was maintained throughout the experiments. Two different calculation methods were used to obtain the diffusion coefficient and the surface indigo concentration in the film. Similar surface indigo concentrations were obtained from the two methods, but a lower diffusion coefficient was obtained by the approximate integral method. It was found that the dyebath pH is the dominant factor influencing the rate of diffusion of indigo and the colour yield of the dyed film. The dyebath pH also had a considerable influence on the reduction of indigo to leuco-indigo, a step that is essential to the dyeing process.     

青黛在涤纶织物上染色性能的研究

采用天然染料青黛对涤纶织物进行染色,研究了各因素对染色效果的影响.结果表明:pH值4～5,温度120～130℃,时间30分钟,染色效果最好.载体可实现青黛对涤纶在100℃下的低温染色.青黛对涤纶染色后具有较高的水洗牢度和摩擦牢度.     

Fading of Cotton Yarn Colored with C. I. Vat Blue I (Indigo Dye) via Ozone Application

In this experimental study, the possibility of obtaining of fading effect to indigo dyed denim yarns via ozonation process was searched. Therefore, a novel approach was attempted for fading the denim materials in the form of yarn before weaving or garment processes. The effect of the ozone gas on the CIELab values of indigo dyed yarn specimens was statistically investigated depending on some physical properties of the yarns and application parameters of ozone gas. In addition, the effect of ozone gas on the strength performance of the yarns was investigated. The results showed that different yarn and ozone application parameters affected the fading results. Besides, the ozonation process did not have a crucial negative effect on yarn strength.     

A study on the exhaust dyeing of various synthetic fibres with indigo

Various synthetic fibres, namely, polyethylene terephthalate, nylon 6.6, acrylic and spandex fabrics, were dyed with indigo blue using an exhaust technique. The factors studied were sodium dithionite and sodium hydroxide concentrations, liquor/material ratio, dyeing temperatures and process times. The pH levels of the dyebaths were achieved by controlling the ratios of sodium dithionite and sodium hydroxide concentrations. Dyebath analysis at the end of dyeing showed that, in different pH regions, different forms of the indigo existed and each one exhibited different degrees of substantivity for synthetic fibres. The nonionic form exhibited substantivity for all the synthetic fibres, while the mono‐sodium phenolate form showed substantivity only in the acidic range. Synthetic fibres could best be dyed in the pH range of 5.5–6. Reflections spectra showed that indigo in synthetic fibres and when dissolved in dimethyl formamide absorbed maximally at 610 nm, while in cotton indigo absorbed at 660 nm. The fastness properties were measured and the results showed that washing and rubbing were good, while light and sublimation were moderate to poor.     

Dyeing behaviour of hydrogenated indigo in electrochemically reduced dyebaths

The dyeing behaviour of hydrogenated indigo, in electrochemically reduced dyebaths, was studied on cotton yarn with particular focus on dark shades. Indigo concentration in the dyebath was studied from 0.9 g l^?1 indigo to 7 g l^?1 to achieve indigo fixation near the level of dyestuff saturation. The number of repetitive cycles of immersion into the dyebath and air oxidation was increased up to eight dips. The highest K/S value at 660 nm was measured with K/S 31 at samples dyed with eight dips in a dyebath containing 1.8 g l^?1 indigo and at a bath pH level of 11.7–12.1. When comparable amounts of indigo had been fixed on the yarn from baths containing 3.5 or 7 g l^?1 indigo, K/S values decreased; however, darkness in terms of L* value increased. Analysis of the reflectance curves between 400 and 700 nm proved that the visually perceived increase in darkness was caused by lowered reflectance in the wavelength range of 400–525 nm. This also explains the more reddish, duller shade of indigo dyeings obtained from baths that contain a relatively high indigo concentration. Comparison to reference experiments confirmed that cathodic dyebath reduction does not modify the dyeing behaviour of indigo.     

Modified Indigo Method For Gaseous And Aqueous Ozone Analyses

The indigo method developed by Bader and Hoigné for aqueous ozone analysis was modified to allow for both gaseous and aqueous ozone determination. Gas or water samples were extracted with a gas-tight syringe containing a known volume of indigo reagent. The modified procedure provided a more consistent basis for gaseous and aqueous ozone determination allowing for more accurate ozone mass balance calculations. Direct gaseous ozone UV absorbance with molar absorptivity of 3,000 M^?1cm^?1 at 258 nm was used as primary standard to determine the molar absorptivity of the indigo reagent. The molar absorptivity of indigo reagent, assuming a 1:1 stoichiometric ratio for the reaction between indigo and ozone, was determined to be 23,150 ± 80 M^?1cm^?1, or approximately 16 percent higher than that of 20,000 M^?1cm^?1 suggested by Bader and Hoigné. An independently calibrated membrane-electrode ozone monitor showed good correlation with indigo method results using the molar absorptivity value determined in this study. The apparent molar absorptivity of aqueous ozone at the wavelength of 258 nm measured by the modified indigo method increased from 2,400 to 3,600 M^?1cm^?1 in the investigated ozone concentration range of 0.4 to 11.0 mg/L. This variation might have been caused by the inherent interference of unidentified ozone byproducts, which presence was supported with scanning spectra in the wavelength range of 200 to 300 nm.     

Dyeing of cotton with indigo using iron(II) salt complexes

The use of gluconic acid as a ligand for complexing iron(II) salts and for vat dyeing of cotton has been reported previously. The present paper reports the observations on the use of iron(II) salts complexed with such ligands as tartaric acid and citric acid for the reduction of indigo at room temperature and subsequent cotton dyeing. This study includes the measurement of reduction potentials of various iron complexes, their effect on dye uptake and the deposition of iron on dyed fabric.     

Effect of corona discharge treatment on indigo dyed cotton fabric

The present study proposes new conditions for achieving the aged-look effect of denim. Indigo dyed cotton fabrics were treated by corona discharge at different power levels and number of passages. Colorimetric parameters of corona treatment were assessed by the CIE L*a*b* colorimetric system and the pH and colour fastness of samples were tested. The surfaces of dyed samples were studied by scanning electron microscopy and Fourier Transform–infrared/attenuated total reflectance (FTIR/ATR) analysis. Under the same conditions of corona treatment, the faded-look effect was reduced as the depth of dyeing was increased. Increasing the power and the number of passages increases L* and b * and decreases a * values. This indicates that samples become lighter and yellower but soaping can reduce yellowness. FTIR/ATR results show that indigo dye oxidises, and isatin and anthranilic acid are produced. The pH levels of corona-treated samples reduce as the power and number of passages increase. This acidification is in agreement with the results of FTIR/ATR analysis.     

Electrochemical decolourisation of dispersed indigo on boron-doped diamond anodes

In denim production the decolourisation of intensively coloured, indigo-particulate containing waste water is a factor of major environmental concern. Successful anodic decolourisation of solutions containing 0.29 mM dispersed indigo and 0.070 M Na₂SO₄ could be achieved on boron-doped diamond electrodes. Current densities were varied from 0.36 to 80 mA cm^− 2. Relative current efficiency decreases with increased current density from 43% to less than 1% at 80 mA cm^− 2. At higher concentration of dispersed indigo of 25.1 mM, increased relative current efficiency is observed.Diffusion limited current density for decolourisation of 0.292 M indigo dispersion can be calculated with 0.166 ± 0.007 mA cm^− 2. At the experimental conditions studied, peroxodisulfate, formed as by product of the electrolysis, was found to be ineffective for dyestuff destruction.Experiments in presence of small amounts of chloride proved, that the observed decolourisation of the dispersed indigo cannot be attributed to hypochlorite, formed by anodic oxidation of chloride. While anodic decolourisation of a soluble reactive dye proceeds rapidly, commercial vat dyes resist to oxidative anodic attack at the conditions chosen.Bleach experiments of dyed fabric failed, which supports the model of indigo oxidation in the diffusion layer of the anode.