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The article describes an experiment which integrated physical colors onto already produced textile fibers and fabrics, either for sensors or as an alternative to dyeing. Several layers of alternating refractive index were built on both flat glass and glass fiber using the ionic self-assembly technique. Results of the experiments showed that both PEI/SnO2 (A) and PEI/SiO2 (B) drift in reflectance peak with the increase in their thickness, with the thickness of each film corresponding to be an exact quarter of the principal wavelength. This experiment, demonstrated a very predictable, automated, and controlled process to physical colors for textiles

The article examines the strength of the relationship between just noticeable color differences and unique hue stimulus selection. First, the article defined extreme and determined how extreme choices were signified as this played a critical role in the analysis of the data. Several approaches were then discussed to determine the extreme cases. However none of the discussed approaches showed a significant correlation between unique hue choice and the arrangement of the Farnsworth Munsell hue test plugs.

The article explains the reason Big Information Technology (IT) systems which store item data such as fabric weight, fiber content and price about a wide range of products, do not handle color data. The article also discusses the commercial opportunities from Big IT systems handling color data. In discussing the opportunities, two major problems for color critical or color relevant industries emerged which were then addressed. And finally the article explains how the color web services can make Big IT handle color data.

The article provides information on the implication of the saturation capacity of the cellulose fibers on reactive commercial dyes. It elaborates the theoretical solution employed in the attempt to understand the actions that have taken place during the process of multi sorption. The sorption of hydrolysed dye is noted to have achieved about 100% less than the reaction from which reactive dye is applied. The differences are inferred to potentially be given another orientation on the bonding group of dye and fiber. Meanwhile, illustrations of the chemical reactions of each dye used are also presented.

The article presents a study on grafting acrylic monomers into textile fibers in order to improve its properties. It states that the grafted polyesters are characterized and their dyeing and color properties are examined with selected disperse dyes. Results show that anthraquinone dyes provide photoprotection or photosensitization depending on the particular fiber-dye combination. It mentions that fluorescent brighteners on wool cause photoyellowing and photodegradation to protect wool from deterioration. In addition, alkali-treated polyester fabrics adsorbed more dye to deeper and slightly different shades than untreated polyester depending on the structure and molecular size of the dye.

The article presents a study which evaluates the effect of specimen presentation to the instrument and the effect of specimen pressure on CIELAB measurements of fiber specimens. The study uses different fiber samples such as natural and synthetic fibers, which are measured at different pressures. It uses a Hunter LabScan XE Spectrophotometer instrument for taking CIELAB measurements. Results show that CIELAB measurements change as pressure in the fiber cell increases. It suggests the need for a standard measurement procedure which specifies pressure in measuring color of fiber samples.

The article presents a study on colored staple fibers such as black, dark brown and dark blue which are blended with other lightly colored fibers in order to achieve specific and aesthetic effect. It states that same dye-concentration gives lower optical effect by the greater incoherent dislocation of dyes molecule in the fiber textile system. The study used fibers which were mass pigmented and colorless cellulose viscose. It notes that blend-homogeneity is maximal and the visual and objective chromacity-impression does not change. It is inferred that surface fiber ratio in melange cause easier color prediction in melange from fibers of all fineness.

The article analyzes the effects of increases in temperature and pressure on shade in the stock dyeing of polyethylene terephthalate (PET) fiber using disperse dyes with supercritical fluid (SCF) CO2. Recirculation of SCF demonstrated more uniform dyeing than those without but have no significant effect on shade. No significant differences were noted in terms of dye in the fiber and surface dye between the SCF and conventional aqueous dyeing using the commercial disperse dye known as Red 1A. Fibers dyed with SCF demonstrated darker shade than the aquaeous dyed fiber and were uniformly dyed.

Because colorimetric and colorant formulation calculations require some time, even with a modern computer, the monitor screen display is usually frozen. Programmes used in commercial software are not accessible, for obvious reasons, and the operator has no opportunity to understand and or learn about what is being computed. This paper describes software for colorimetric and colorant formulation calculations, which presents each step of the particular calculation, by gradual display on the monitor screen, and explains what the computer is doing at each stage in the process. The operator now has an opportunity to see how the calculations are carried out, giving him a better understanding of the sources of imprecision and the ability to better evaluate existing and new software. Some of the problems which arise in colorant formulation are discussed in the latter part of the paper. [ABSTRACT FROM AUTHOR]

For the continuous dyeing of cellulosic fiber, using monochlorotriazine type fiber reactive dyes, a single-bath pad-thermofix process is employed. Recently a method has been developed for use with hetero-bifunctional fiber reactive dyes. This method involves a two-bath pad-steam process and produces reproducible dyeings which exhibit a high degree of fixation, good wet fastness, good handle and good appearance, with the additional advantage of low loading of effluent. [ABSTRACT FROM AUTHOR]

Neps of immature cotton fibers appear as light or white specks in a dyed fabric, making fabric appearance unacceptable. With a view to covering neps, a pretreatment based on the application of chitosan (a partially deacetylaged poly-N-acetyl-D-glucosamine) was investigated. It was found that the addition of salt after sorption of chitosan, followed by rinsing, enabled the cotton to be dyed with direct or reactive dyes in the same bath by the exhaust process. On dyeing with direct dyes, neps were completely covered, color yield improved and deeper shades were realized. Reactive dyes were not as effective as direct dyes in covering neps. Compared to the untreated fabric, however, the pretreated fabric gave improved nep coverage. The effects of various aftertreatments on the colorfastness properties of the direct-dyed fabrics were also examined. The nep-covering pretreatment by the exhaust process can be easily incorporated into the conventional preparation sequence and is less expensive than pad/bake or pad/batch processes. [ABSTRACT FROM AUTHOR]

After-rinsing and washing of fiber reactive dyes has long been a water and time consuming portion of the dyeing cycle. In order to better understand the mechanism which governs the rinsing and washing steps, a system was developed to visualize and to give quantitative measurement of this process. By so doing, variables such as temperature, pH, electrolytic concentration, and flow rates can be monitored, compared, and optimized. Wetfastness problems associated with fiber reactive dyes have been traced to inefficient removal of the unfixed hydrolyzed dye. Rinsing and washing parameters can greatly influence this process. By optimizing these parameters, wetfastness properties are also optimized. Cost savings resulting from a reduction in water, energy, and time can be realized without a sacrifice in quality. Further savings through reduced waste water fines and penalties may also be realized. [ABSTRACT FROM AUTHOR]

Methods for coloring nonwovens involve technology also used in the coloration of paper and traditional textiles. Although the nonwovens industry encompasses a wide variety of fabric types and compositions, coloration procedures are limited compared to the more diverse range of processes and colorants used for woven and knitted textiles. Refinements in processes and products used in coloration have been necessary to meet the special requirements of nonwovens. Some of the more commercially significant coloration procedures relating to nonwovens are reviewed, including coloring of cellulose pulp in a wet-laid web forming process and incorporation of color in synthetic polymer melts/solutions prior to spinning fibers. Application of pigment colors with latex binder is a coloration method used on a variety of nonwoven substrates, especially where latex binders are used for web bonding. The problem of migration of pigment and binder during drying can be minimized using chemical additives. Other topics covered are dyeing of polyester webs with disperse dyes, printing, and use of fluorescent whitening agents. [ABSTRACT FROM AUTHOR]

Defining the strengths and weaknesses of acrylic and modacrylic fibers has led to an understanding of ways that they can be made more useful to the trade. The currently limited markets for modacrylic fiber are expanded through development of a pigmented flame retardant fiber with excellent sunlight, chemical, and physical properties. Fiber development stages included market definition, pigment selection, preparation of color-stable dispersions, and engineering of a method for both pigment incorporation and automated color control. The pigmentation technology may provide a useful route to achieve other properties desired by the trade. [ABSTRACT FROM AUTHOR]

To realize the maximum benefit from on-line color measurement, the user must be aware of both the factors which could cause shade changes and the potential magnitude of the changes which can occur between the goods exiting the dry cans and their final color evaluation as finished goods. This paper examines the causes and magnitudes of such color changes for cotton fabrics dyed with selected fiber reactive and sulfur dyes and finished with a durable press finish. The numerical color information, gathered at the end of the range, must be readily understood by the dyer, so that any appropriate corrective action can be taken for goods still to be dyed and so the color of finished goods can be accurately projected. This paper proposes wider use of relative color strength and CMC (1:1) color perceptibility arithmetic for online color measurement data output. [ABSTRACT FROM AUTHOR]

The objective of foam sizing like other textile foam processing is to reduce wet-pick-ups and to conserve energy and increase throughput during drying operations. In foam sizing a concentrated size composition is mechanically foamed at room temperature and is applied to the warp yarns by the Reed-Chatwood applicator. The main feature of the applicator is a horizontal padder with a separator gate to stop contact of the foam and yarn when the slasher stops. The foam collapses at the nip of padder applying the size uniformly to warp yarn at a low wet-pick-up. The size add-on is controlled by foam stability, blow ratio and solids present in the mix. Due to reduced pick-up it appears that less bridging of yarns occurs and the sheet is more easily split reducing yarn hairiness. For colored yarn warps foam application also results in less color bleeding and staining of adjacent yarns. This paper reviews critical factors in the development of foam sizes and results from production trials and outlines its economic implications. [ABSTRACT FROM AUTHOR]

The actual production units which allow to control the main parameters of the dyeing cycles -- or each kind of fibres and textile materials -- temperature, dosing of chemicals and dyes -- together with the latest knowledges concerning controlled adsorption to ensure the levelness and the reproducibility of dyeings even having the best possible fastnesses, have been the basis for further developments allowing to take care of the physical properties of the dyed material. Additionally to the concept "quality" it has been necessary to pay more attention to the concept "workability" of the dyed material in order to achieve the best performances in the following manufacturing operations, including the confection in apparel. Even using the above mentioned technologies, it is impossible to keep during the whole dyeing process the same mechanic and hydraulic conditions, without any damage to the dyed material. A complete concept and the corresponding production units and peripherical devices have been developed with the help of microprocessors, in order to coordinate all the parameters and get the necessary information on the actual performances of the dyeing machines, as well as on the behaviour of the material which has to be dyed, using it as feed-back for further monitoring of the whole process, including the control of the physical characteristics of the material. [ABSTRACT FROM AUTHOR]

The solubility parameter concept offers a method for quantifying the miscibility or compatibility of two or more liquids. The concept can also be applied to polymer systems, and in the textile area the disperse dyeing of polyester may be treated from the viewpoint of a solution of dye in the fiber. Some of the perhaps puzzling observations of the effects of dyeing auxiliaries on the exhaust dyeing process may be at least qualitatively understood by reference to the solubility parameters of fiber, dye, and auxiliary. Although solubility parameter alone is not a sufficient basis for the explanation of all polyester dyeing phenomena, it can serve as a medium for the removal of some aspects of dyeing from the realm of necromancy. [ABSTRACT FROM AUTHOR]

During the last years, the main object and emphasis when developing yarn dyeing processes was to obtain economical and ecological advantages in dyeing. In doing this, consideration has not always been given to the fact that the dyed yarns have a decisive influence on the subsequent operations, such as, for instance, weaving and knitting. Taking into consideration the total cost of textile processing then new aspects have to be taken into account. The knowledge gained by the latest developments with regard to optimizing dyeing processes will be of great help. The basis for this is that not only partial processes are optimized, but that such aspects are taken into account which include the calculation of the total manufacturing costs of textile processing. Thus the most important parameters of dyeing processes have been analysed which hive a bearing on the economy of dyeing, drying, and other operations in subsequent processes; such as: liquor ratio, rate of flow, reversal of flow direction, etc. without neglecting secondary parameters such as shape, size and weight of the yarn packages having a vital effect on the hydraulic efficiencies of the yarn dyeing machines. The conclusions of this study have shown the necessity of new conditions to be observed in dyeing. Applying these conditions in dyehouses is, no doubt, a function of the infrastructure about the mutual understanding with the buyers of dyed yarns. The existing problems are being presented together with ways and means how they can possibly be overcome. Last not least, thoughts and ideas will be expressed in this connection which do nothing but truly affirm and confirm the implementation of the well known concept of short liquor yarn dyeing methods. [ABSTRACT FROM AUTHOR]

Interactions between dyes and fibers and dyes and auxiliaries are known to cause color differences on dyed textiles as well as differences in the depth of shade observed. Such interactions are particularly noted on fibers from thermoplastic polymers such as polyester and nylon that have been dyed with disperse dyes. Disperse dye-fiber substrate interactions and the effect of auxiliaries on such interactions are reviewed for nylon and polyester fibers. Recent studies demonstrating the nature of color differences within three different types of heat set polyesters dyed with three 1,4-disubstituted anthraquinone disperse dyes in the presence and absence of a nonionic surfactant (Triton X-100) are described. Also, effects of solvent and base/solvent pretreatment on the dyeing properties and color differences observed within a polyester are described. [ABSTRACT FROM AUTHOR]

While a two-phase model of crystal chunks in an amorphous matrix is qualitatively very useful in predicting polyester dyeing behavior as well as several mechanical properties, there is much about the structure of polyester fibers that we do not yet understand. New research in which amorphous regions are selectively removed, leaving the crystalline regions for examination by electron microscope and other tools, shows much promise. In the instance of oriented PET fibers, helical crack formation disrupts the selective process and efforts to avoid this chemical degradation stress cracking are in progress. [ABSTRACT FROM AUTHOR]

In the years since energy became scarce and expensive, numerous textile dyeing operations have implemented efforts to reduce energy consumption by increasing their energy efficiency. Energy efficiency is a product of many things - procedures, machine and labor productivity, waste, heat recovery, all of which should be considered in any practical approach to dyehouse energy conservation. [ABSTRACT FROM AUTHOR]

The article presents a study on the effects of detergents on colorfastness of vat and azoic dyes in perchloroethylene. For the study, researchers applied three surfactants and two concentrations. They treated the colored textile fabrics with drycleaning solvent under the designated conditions. They found that the solubility of vat and azoic dyes can be improved or reduced at a specific hydrophilic-lypophilic balance because surfactant molecules possess a polar and a nonpolar part. They also found little affinity between vat and azoic dyes in organic solvents and cellulosic fibers.

A large amount of carpet is made from space-dyed yarn or is continuouly dyed in the piece. In either case, the dye recipe(s) are made in bulk in a tank and fed to the fiber during the production run. There is an opportunity to check the ingredients of each batch of dye by colorimetric means before the dye is applied and correct any variations from the desired amounts. Although measurement of soluble dyes in solution is a well understood method, it is not in widespread use to check batches of mixed dyes. It is presumed that known techniques are too time-consuming or that the results are not sufficiently accurate. Successful color control can be achieved with adequate precision if newly developed solution-measuring equipment and time-saving methods are used to support the production of dyed material . [ABSTRACT FROM AUTHOR]

The history of the blade shape squeegee systems for textile printing shows a development from hard stiff materials through soft and flexible rubber materials towards the optimal combination of flexible metal blades with a stiff synthetic contact surface. The build-up of pressure in the angle between squeegee blade and screen; and related to this angle the colour supply, is analysed by computer calculations related to a physical model. This analysation showed that it is desirable to have a complete separation, in the technical lay-out of the squeegee system, between angle adjustment and the pressure on the nip of the squeegee blade. It is of eminent importance to have continuous adjustment facilities, also during printing, of these two phenomenons. [ABSTRACT FROM AUTHOR]

To Improve dye house control, one must be cognizant of the "vital signs" making up the dye house variables. When organization and procedures are present, these variables can be inspected daily with a minimum amount of time. Many basics must be controlled in a dye house. This report lists these basics with points of interest and specifics for each one. Because one variable has affect on another variable, control must continually be present. [ABSTRACT FROM AUTHOR]