Acrylic Fabrics Research Articles

Towards a universal dye class for printing on multiple substrates

Textile printing using dyes requires different dye classes to be used for different substrates, which increases complexity in the printing operation. The development of a single (universal) class of dyes that can be applied to all fibres to produce prints with excellent technical properties is desirable. Reported is one approach to a universal dye class for printing on multiple substrates. A temporarily water soluble fibre‐reactive dye, 2‐[(4‐{(E)‐[4‐(diethylamino)phenyl]diazenyl}phenyl)sulphonyl]ethyl sodium sulphate, was synthesised and printed on cotton, polyester, polyester/cotton blend, wool, nylon and acrylic fabrics. A print–dry–cure process was employed. Bright, level prints with high colour strength, good rub fastness and fair to good wash fastness were obtained for all substrates except acrylic, which did not produce good prints. However, significant amounts of unfixed dye were removed during soaping.

Wettability measurements on plasma treated synthetic fabrics by capillary rise method

The capillary rise method was applied to evaluate the improvement in water uptake of polyester and acrylic fabrics obtained by plasma treatment. Power, exposure time and gas type (nitrogen, air and oxygen) were considered as plasma variables. After plasma treatment, fabric samples were tested through capillary rise of water. The processing of a set of height absorption values vs. time, until equilibrium is reached, allows characterisation of the wettability of samples by three parameters. The influence of plasma variables on these parameters was studied.

Acrylic Fabrics Treated with Plasma for Outdoor Applications

The increasing interest in the application of plasma processes on textiles is due both to the necessity of adding value to products and to develop new pollution free technologies. In fact, plasma treatments allow modification of the textile surface behaviour with a flexible process, which can impart particular properties to the fabrics, such as waterproofing, oil repellence, antistatic behaviour, etc. In addition, plasma processes are characterised by the very small quantity of chemicals involved and by the absence of solvent or water, which are usually employed in traditional finishing processes. In this work the effect of different plasma treatments on the properties of acrylic fabrics for outdoor applications was explored. In particular, the possibility of substituting plasma processes for the traditional cleaning and waterproofing processes of outdoor acrylic fabrics was evaluated. The properties of the plasma treated acrylic fabrics have been compared with the characteristics of the fabrics traditionally treated. The resistance of plasma treatments to wear, UV and weather exposure has been also evaluated.

Effect of copper treatment on the dyeability of gamma irradiated acrylic fabrics with different dyestuffs

The effect of Cu (II)/hydroxylamine mixture on the dyeability of acrylic fabrics towards direct dyes was investigated. The effect of the different factors that may affect the dye affinity of acrylic fabric such as composition and concentration of copper sulphate/hydroxylamine mixture, irradiation dose, pH strength of the dye bath, dye concentration, dyeing temperature and time was studied. It was found that by using a mixture composed of 2% copper sulphate and 1% hydroxylamine constituting a total concentration of 3 wt.% (based on fabric weight), the dye affinity of acrylic fabric for the direct dye Benzamine Bordeaux FB was significantly improved. Also, it was shown that the dye affinity of the acrylic fabrics for other dyestuffs such as reactive and acid increases with increasing concentration of such mixture. Irradiated acrylic fabric showed a higher dye affinity for the used dyes compared to the unirradiated fabrics. Fabrics irradiated to a radiation dose of 1 Mrad showed the highest dye affinity with high leveling of dyeing. The pH strength of the dyeing bath at which the highest colour strength obtained was 3. A mechanism was proposed for the dyeing of acrylic fabrics with direct dyes in the presence of copper ions.

Antibacterial activities of acrylic acid-grafted polypropylene fabric and its metallic salt

Antibacterial activities of acrylic acid-grafted polypropylene fabric and its metallic salt

Hydrophobic Interaction and Its Effect on Cationic Dyeing of Acrylic Fabric

The influence of electrolytes on the mechanism of cationic dyeing of acrylic fabric has been investigated in terms of ionic and hydrophobic interactions. The effect of salt on hydrophobic interaction is reviewed and used to explain the "unusual increase of dye sorption which occurs at salt concentrations up to 0.5 mol/l," described by Alberghina and co-workers. Thermodynamic analysis suggests that the ionic distri bution coefficient of the dye ( KD ) is a function of chemical potential changes due to hydrophobic interactions. Therefore, KD depends on the type and concentration of electrolyte in the dyebath.

A New Approach to the Study of Textile Dyeing Properties with Liquid Chromatography

Frontal analysis gives retention volumes of basic dyes on acrylic fabric, rolled and inserted into a liquid chromatography column. The retention volumes indicate differences in adsorption and therefore in compatibilities of standard dye mixtures. A simple and useful relation, Cv = Cvo + mR - Cv,0, results where m is a parameter fitted to the data, Cv0 is the compatibility difference between Cvo and Cv when R = 0 ( i.e., elution times are identical), and Cvo is the compatibility of one of the two dyes in the mixture. Hence, a new approach is proposed that not only allows determination of Cv using frontal analysis with an LC apparatus, but also defines compatibility in an objective manner as a continuous function.

Drying of Latex Backcoated Acrylic Fabrics: Heat Transfer Coefficients

Drying and curing tests were performed in a laboratory scale dryer on dyed tufted acrylic fabrics and the latex adhesive backcoating to obtain heat transfer coefficients as a function of the mass velocity of air flowing through the fabric. Treating the fabric as a packed bed of cylindrically shaped fibers, equations were developed making it possible to calculate the flow-through velocity Gtf from measured air velocities directed at the upper and lower faces of the fabric. Correlations obtained for the heat transfer coefficients were h = 2.22 Gtf0.47 for fabric drying and h = 4.84 Gtf0.32 for curing the latex adhesive backcoating ( h in W/m2 K, Gtf in kg/m2h). These results were compared with earlier investigations of the drying in packed beds.

Soil Remaining on Fabrics after Laundering as Evaluated by Response Surface Methodology

Response surface methodology was used to visualize the interactive effects of de tergent concentration, agitation time, and wash temperature on removal of soil from fabrics. Plots of the whiteness index of fabrics after repeated soiling and laundering indicated that maximum whiteness occurred at approximately 0.20% detergent con centration. The wash temperature required for maximum whiteness varied with fabric type. Changes in length of agitation time within the limits of the study had a minor effect on soil removal. Labeled components of synthetic sebum could be completely removed from acrylic and nylon fabrics. Both polar and nonpolar components became trapped in the cotton fibers. Removal of nonpolar triolein from polyester was in complete and decreased as wash temperature increased. Particulate soil, as measured by x-ray fluorescence of silicon, could be completely removed from all fabrics except the acrylic.

Determination of the Finish on Flame‐retarded Acrylic Fabrics by an Infra‐red Spectroscopic Reflection Technique

The use of the f.m.i.r. technique in i.r. spectroscopy is proposed for the determination of the finish in flame‐retarded acrylic fabrics. The spectrum band occurring at 2250 cm‐1, which corresponds to the nitrite group, is used as an internal standard in the fabric/finish absorbance relationship and this enables the concentration of finish on different flame‐retarded specimens to be measured.

DRYING PROCESSES OF ACRYLIC FABRICS AND THE MEANING OF THE DECREASING COEFFICIENT, <i>k</i>

Drying properties of regular and modified acrylic fabrics were studied. A modified acrylic fabric has many micropores in the fiber. The infrared analysis indicates that the regular fabrics have almost the same chemical moieties as the modified, whereas their sorptive behaviours are different each other.The measurements for drying processes were carried out in a box at 20°C and 63% R. H. All of drying characteristic curves showed convex upward. In the preceding report, the following characteristic equation (1) was proposed for drying process. The decreasing coefficient, k, was determined by the slope of the following equation (2). k became larger in order of wool, cotton, modified acrylic fabric, nylon, regular acrylic fabric. The k value for the modified acrylic fabrics were nearly same as that for cotton. Plots for the free moisture content versus the reciprocal of the decreasing coefficient also gave a straight line.

Soil-Release Properties of Acrylic Fabrics After Controlled Alkaline Treatments

Soil-Release Properties of Acrylic Fabrics After Controlled Alkaline Treatments

Studies on Sorption of Solubilized Water by Textile Fibers in Nonaqueous Solution. II.

The moisture regain of textile fibers and the water content in solution equilibrated together with them were determined in the presence of various amounts of water solubilized by 0.1M Aerosol OT in perchloroethylene at 10, 20, and 30°C. The vapor pressure of water over the solution was also measured at each temperature. Rayon, wool nylon, and acrylic fabrics were used as test fibers.The sorption of solubilized water by the fibers from perchloroethylene is exothermic below 75% relative humidity. The sorption isotherms are sigmoidal in shape like those of the sorption of water vapor by the fibers in humid air.The values of parameter C in the Brunauer-Emmett-Teller equation were calculated as a function of the moisture regain of the fibers. The values of parameter C decreased as the moisture regain of the fibers increased. The heat of adsorption of water E1 and EAV, for the first layer and for the average of total amounts of water molecule adsorbed by the fibers, respectively, were calculated from the temperature dependence of parameter C, and it was found that the values of both E1 and EAV decreased as the moisture regain of the fibers increased. The values of EAV thus obtained were in good agreement with the heat of adsorption obtained from the change by temperature of vapor pressure of water adsorbed by the fiber, which was reported in the previous paper.

Combustion gas toxicity of textiles (author's transl)

Textiles are used so widely as interior materials of many buildings, houses, and transportation facilities, that the combustion gas has a chance of intoxication of a fire accident. Therefore this investigation was undertaken to clarify the toxicity of the gas and to obtain an index for safety standards in such cases. The combustion gases of cotton, polypropylene, acrylic, flame retardant (F.R.) cotton and F.R. acrylic fabrics were analyzed by a gas chromatograph and a GC-Mass spectorograph, and also tested with experimental animals to determine the lethal factors including blood gas analyzing technique. The gas exposuring test based on gas analysis data showed that the toxicity of these combustion products increased in the following orders: cotton, polypropylene, F.R. cotton, F.R. acrylic and acrylic. Comparative indices of the toxicity showed that acrylic increased 7.26-fold as compared with that of cotton. It was recognized that the lethal factors in the mice was due to carbon monoxide and/or hydrogen cyanide during the exposure one hour, and that sequelae due to acrolein during the seven day observation period after the exposure. Flame retardant treatment increased twice the toxicity of cotton. On the contrary, that of acrylic was reduced by 0.8 time compared with the original fabric, so that the treatment could be recommended only in case of acrylic from the safety standpoint. From the above results, it can be stressed that vigorous smoke exhaust procedure should be executed in the case of fire accidents for saving human lives.

The Relationship of Directional Reflectance Properties to Acrylic Pile Fabric and Fiber Characteristics

Directional reflectance curves measured from acrylic pile fabric of various luster levels by means of the Hunter Model D-10 Recording Goniophotometer were subjected to detailed examination and analysis. The relationship of various luster-related curve properties to fabric and fiber characteristics was examined. A statistical curve-analysis technique is shown to produce the disperison index and kurtosis index, parameters which are useful for further quantization of directional reflectance curves. Dispersion index values are related to uniformity of pile lay, straightness of fibers, and basic fiber luster. Kurtosis index gives values related to "sharpness" of the luster.

The Tumble-Drying Process and Acrylic Knitted Fabrics1

The tumble-drying process is discussed relative to its effect on the dimensional stability of acrylic knitted fabrics. Area shrinkage of these fabrics increases with increase in tumble-dryer temperature. Cycling of the temperature during drying is shown to contribute significantly to variability in fabric shrinkage. Fabric compaction or compression during tumble drying is shown to promote longi tudinal or along-wale loop slippage, if the stitch length is sufficiently large so as to allow free distance between loop apices in adjacent rows of needle and sinker loops. Loop slippage is shown to occur without appreciable relaxation shrinkage under certain conditions during tumble drying after dry cleaning. The mechanism of compressional shrinkage is proposed as an explanation of some anomalies involving tumble drying reported in the literature.

The Dimensional Stability of Acrylic Knit Fabrics

Fabrics knit from three different stable acrylic yarns have been examined for dimen sional stability both in the dry relaxed form and with length distortion. Three methods of wet relaxation were employed: wetting and drying at 115°C, immersion in boiling water, and tumble drying. While acrylic knit goods are similar to comparable goods knit from cotton or wool with respect to wet relaxation shrinkage, two important differences are demonstrated. First, the minimum temperature at which relaxation shrinkage occurs is well above room temperature. Secondly, the equilibrium loop shape is shown to be a function of the thermal history of the fabric.

THE DYEING OF NEW YARNS AND FABRICS

The dyeing properties of the new synthetic fibres are reviewed under selection of dyes and the application of dyes, new techniques such as “carrier” dyeing and high-temperature dyeing being briefly described. The dyeing of novel yarns and fabrics made from these fibres is described, sections being devoted to high-bulk acrylic yarns, textured yarns, stretch yarns and novel woven fabrics. Particular emphasis is placed on the precautions that must be taken during the dyeing process in order to maintain the novel effects which have been inserted in the goods.