The effect of nano‐ and micro‐TiO2 particles on reflective behavior of printed cotton/nylon fabrics in vis/NIR regions

To match the reflectance profile of desert colors including brown, olive green, and khaki in the Vis/near IR (NIR) bands, several pigments were used to print cotton/nylon fabrics. The reflectances of printed fabrics were measured by using spectrophotometric technique. TiO₂ microparticle and nanoparticle powders were also added to the printing pastes to evaluate their effect of reflectance, light, rubbing, washing fastnesses, and colorimetric values of each sample. Tuning the reflectance behavior of each color was successfully managed using specific pigments along with TiO₂ particles. NIR reflectance of brown, khaki, and olive green printed fabrics was enhanced by presence of TiO₂ in printing formulations, which is in complete agreement with the Kubelka–Munk theory. NIR enhancing effect of TiO₂ particles was fast against rubbing, washing, and light exposures while it could significantly change the visible appearance of the printed patterns even at concentrations as low as 0.25 g/kg. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2012     

Properties of ink‐jet printed,ultraviolet‐cured pigment prints in comparison with screen‐printed,thermo‐cured pigment prints

A collection of printed fabrics for men’s shirts was designed and prepared using computer‐aided design/computer‐aided manufacturing technology. The colours for designs were ink‐jet printed on cotton fabrics with pigments and ultraviolet‐cured. These prints represented the target colours for subsequent flat‐screen printing, which was performed using pigment printing pastes and thermal curing. For an exact transfer of colours of the ink‐jet‐printed standard into the screen‐printing process, a computer recipe prediction method was used. A comparison of colorimetric parameters of fabrics printed with both printing techniques shows minimal and acceptable differences in the CIELab colour values. A comparison of colour fastness properties proves that very good colour fastness is achieved on the pigment‐printed fabrics produced with both printing techniques. The flat‐screen‐printed fabrics show better colour fastness to washing, perspiration and rubbing, while ink‐jet‐printed fabrics show better colour fastness to dry‐cleaning and light. The fabrics printed with both printing techniques have high rigidity and non‐elastic properties. The mechanical and physical parameters are strongly dependent upon the amount of the dry substance of the printing media applied on the cotton fabric surface, which is higher on screen‐printed fabrics. The ink‐jet‐printed fabrics show better air permeability than flat‐screen‐printed fabrics.     

Comfort and reflectance properties of viscose/polyester blend fabric printed by vat/disperse dyes in visible/near-infrared region

In this study, a viscose/polyester fabric was printed by disperse and vat dyes to match the reflectance characteristics of the NATO black and green hues with forest environment in the visible/near-infrared (Vis-NIR) reflection spectrum. The black and activated carbon nanoparticles were also added to the printing paste to match the reflectance of hues. Color components and Vis-NIR reflective behavior of printed fabrics were measured by reflection spectrophotometer. The rubbing, washing and light fastness, water absorption time, air permeability, bending length, and crease recovery angle of printed fabrics were also studied. Additionally, the strength properties of samples were measured. The reflectance behavior of the samples showed that the use of the black and activated carbon nanoparticles results in diminution of the Vis-NIR reflection. The strength, air permeability, and bending length of printed fabrics have decreased, while the angle of crease recovery and the time of water droplet absorption have increased. The rubbing, washing, and light stabilities of printed samples were also measured as appropriate.     

Diffuse reflectance behavior of the printed cotton/nylon blend fabrics treated with zirconium and cerium dioxide and citric acid in near- and short-wave IR radiation spectral ranges

Near- and short-wave IR emission spectra of printed cotton/nylon blend fabrics coated with inorganic compounds in order to tune their diffuse reflectance behavior to the ones with woodland and desert backgrounds are investigated. In this regard, cotton/nylon blend fabrics printed with a four-color digital pattern were used as the substrate, and different concentrations of zirconium and cerium dioxide (ZrO₂ and CeO₂) with and without citric acid as a cross-linker were loaded on these fabrics using the pad-dry-cure method. The diffuse reflectance of the coated fabrics with various concentrations of nanoparticles and a cross-linker was first measured by near-infrared (NIR) diffuse reflectance spectroscopy (DRS). Then, fabrics with an optimum concentration of nanoparticles and appropriate reflectivity profiles similar to woodland and desert were investigated by field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), washing, and rubbing fastness properties. In general, NIR and short-wave infrared (SWIR) reflectance of fabrics coated with ZrO₂ and CeO₂ nanoparticles in range of 1% to 1.5% (w/v [%]) was suitable for matching with different environments. According to the findings obtained from the durability test, it was concluded that the washing fastness of the treated fabrics with CeO₂ nanoparticles was excellent in both environments. FE-SEM images of the treated fabrics containing ZrO₂ and CeO₂ indicated that the presence of nanoparticles on the surface of fabrics in woodland patterns was greater than the desert ones. However, the coated fabrics with CeO₂ and citric acid in the woodland pattern have shown better dispersion with a mean particle size of 30 to 60 nm.     

Single‐phase ink‐jet printing onto cotton fabric

The current commercial application of ink‐jet reactive inks to cotton fabrics requires pretreating with pad liquor containing a thickener, urea and alkali prior to printing. In this study, attempts have been made to develop a reactive ink‐jet print in a single‐phase process by adding an organic salt to the ink formulation and hence removing the need to pretreat fabrics. This approach utilises inks containing both a reactive dye, in this case Procion Red H‐E3B, and an organic salt such as sodium formate, sodium acetate, sodium propionate or tri‐sodium citrate. The behaviour of a novel reactive ink formulation for ink‐jet printing on to cotton fabric was evaluated at different pH vlaues. The results at optimum pH indicated that printed non‐pretreated fabrics with ink containing organic salts exhibited a higher level of reactive dye fixation than printed pretreated fabric containing no organic salt ink. The yielded prints demonstrate excellent colour fastness to washing and dry/wet crocking properties. The light fastness of the printed fabrics was improved by adding an organic salt to the ink formulation.     

Pigment color printing on cotton and polyester fabrics with electron beam irradiation curable formulations

Accelerated electrons delivered by electron beam accelerator were used to fix pigment colors, incorporated in curable formulation containing diluting monomer and an oligomer, to cotton and polyester fabrics. Tetrahydrofurfurfryl acrylate monomer and trifunctional urethane‐methacrylate (TFUMA) oligomer were used as curable base besides ethylene glycol. The fabrics were printed with these formulations and exposed to various doses of electron beam irradiation generated from the 1.5 MeV (25 kW) electron beam accelerator machine. The irradiation dose, formulation composition, and pigment color concentration were studied. The roughness and color fastness to rubbing, washing, and perspiration of the printed fabrics by electron beam irradiation, were compared to the same fabrics printed by conventional pigment printing pastes. The results showed that cotton and polyester fabrics printed with the pigment colors by electron beam irradiation displayed higher color strength than those fabrics printed by the conventional thermal curing at equal pigment color ratios depending on the kind of pigment color. The durability properties, in term of roughness, rubbing, washing, and perspiration of fabrics printed by electron beam irradiation are better than those printed by conventional thermal curing. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Printing cotton fabrics with reactive dyes of high reactivity from an acidic printing paste

The behaviour of reactive dyes of high reactivity during the printing process of 100% cotton fabrics from an alkaline and acidic printing paste was studied in detail. The printing pastes were stored for different periods of time and then the fabrics were printed. The samples were subjected to two methods of fixation, the first by steaming and the second by thermofixation. The effects of different factors such as alkali and acid concentration, storage time of the printing pastes and method of fixation on the K/S values of the prints were investigated. The fastness properties of the printed areas were also measured to determine the improvement obtained by acidic printing with high-reactivity reactive dyes on cotton fabrics.     

Properties of differently printed and easy‐care finished linen fabrics

Linen fabrics were printed with reactive dyes, vat dyes and pigments. The prints were cured and after‐treated using conventional processes. Printed and unprinted fabrics were finished with low‐formaldehyde resin in a pad–dry–cure process. The mechanical properties (i.e. mass per unit area, flexural rigidity, tenacity at maximum load, wrinkle recovery angles and air permeability) with characteristics of printed and easy‐care finished fabrics were measured and the mutual influence of printing and finishing on these properties was discussed. Moreover, the colour difference between the finished and unfinished printed samples was measured, and the colour fastness to washing, appearance of fabrics after domestic washing, colour fastness to rubbing and light was compared.     

Enhancing the outline sharpness of crosslinked printed cotton fabrics using ethylene glycol diglycidyl ether

In the current study, to obtain environmentally friendly printed cotton fabrics with a clear contour edge, ethylene glycol diglycidyl ether (EGDE) as a crosslinking agent and guar gum as a thickener were used with natural madder dye. The solid content of the thickener was assessed to determine the optimal viscosity of the printing paste. Scanning electron microscopy images and colour depth (K/S) values were used to analyse the surface morphology and printing properties. The pattern outline of the printed cotton fabric was assessed with an optical microscope. Also, the overall fastness properties of the printed fabrics were evaluated. The results showed that when the solid content of guar gum was 2.5%, the viscosity of the printing paste was close to 10 000 mPa.s, which was suitable for printing cotton fabrics. Scanning electron microscopy analysis showed that most of the printing paste was removed during the washing process, and did not affect the microstructure of the cotton fabric. Compared with direct printed cotton fabrics, the K/S values of mordant and crosslinked printed cotton fabrics increased by 3.12 and 4.01, respectively. In the optical microscopy photographs, the mordant and crosslinked printed cotton fabrics displayed a clear outline sharpness of the printed pattern, and excellent printed products were obtained. The colour fastness to washing, rubbing and light of the crosslinked printed cotton fabric were significantly improved, reaching levels of 4-5.     

The application of chitosan in pigment printing

The use of chitosan as a combined thickener and binder in pigment printing has been examined in comparison with a commercial printing system (Alcoprint). Printing pastes made up from mixtures of chitosan, pigment and acetic acid at the appropriate viscosity gave satisfactory prints on polyester and 67:33 polyester/cotton woven fabrics. Rheological data showed the chitosan pigment paste had a much lower yield point than commercial printing paste though no difficulties were found in its use. Curing of the chitosan print at 150°C for 6 min gave samples of comparable colour fastness to the commercial printed samples when subjected to the rubbing and washing tests. The only drawbacks noted in using chitosan in this way were a reduced colour yield and a much higher fabric stiffness.     

Printed thermochromic displays

Thermochromic displays, which were evaluated in this study, combine printed electronics with the thermochromism phenomenon. Conductive lines printed on the reverse side and thermochromic printing ink printed on the front side of cardboard packaging form a thermochromic display that gives cardboard packaging additional value. Displays were printed on different printing materials, and thermochromic printing ink was deposited in one and two layers. In addition, half of the samples were varnished. The influence of the printing material, the thickness of the thermochromic printing ink layer, the varnish, the high temperature, and light fastness on the display's operability were all evaluated. It was clearly shown that the choice of printing material plays a crucial role in the display's operability. Moreover, high temperature and light fastness also have a significant influence, although the impact is negligible when the display is used at room temperature.     

Camouflage of cotton fabrics in visible and NIR region using three selected vat dyes

To provide camouflage in near infrared (NIR) region and imitate reflectance profile of greenish leaves, cotton fabrics were dyed with three selected vat dyes, namely C.I. Vat Blue 6, C.I. Vat Yellow 2, and C.I. Vat Red 13. Reflectance curves of two types of fresh greenish leaves were measured as standard reference. Transmittance curve of vat dyes in acetone solution indicated that selected vat dyes have suitable structure to provide camouflage in NIR region. According to reflectance profiles, reflectance curve of Vat Blue 6 has more similarity with that of green leaf at the concentration of 0.85% owf (on weight of fiber) and 1.2% owf in comparison with those of C.I. Vat Yellow 2 and C.I. Vat Red 13. Cotton fabrics were dyed with different mixtures of the dyes to obtain a standard shade to reach camouflage in visible range. Chromatic values of dyed fabrics were measured (CIE1976 L*, a*, and b*) and two standard shades of the 1948 US army pattern, NATO and forest green, were obtained on cotton fabrics with ΔE_CMC < 2. Reflectance profiles of these two shades were located between the reflectance of green leaves. So, two vat dyes were introduced to camouflage dyes group, C.I. Vat Blue 6 and C.I. Vat Red 13, and used to achieve NATO green and forest green shades for first time. All dyed samples showed good fastness properties. The effect of washing and light exposure on camouflage properties of fabrics in visible and NIR region was inconsiderable. © 2012 Wiley Periodicals, Inc. Col Res Appl, 39, 200–207, 2014     

Optimisation of process parameters of Alpaca wool printing with Juglans regia natural dye

The aim of this research study was to optimise the process parameters of Alpaca wool hand‐knitted samples screen‐printing with Juglans regia natural dye and to set the optimal conditions regarding colour yield, colour fastness and colouristic properties of printed samples. An extensive preliminary examination of the Alpaca woollen yarn and hand‐knitted samples characteristics, the characteristics of suitable thickeners and the optimisation of the printing paste composition, was performed. A starch‐based thickener, British Gum, with a dry matter content of 4% was selected due to its rheological properties responding to properties of the Alpaca yarn and knitwear. It was determined that the fluidity increases while the viscosity and the elasticity decrease in acidic pH, so a pH of 4 was set for the thickener preparation. The thickener of lower viscosity and higher fluidity assures easier pressing of printing paste through the screen, giving uniform colour yield on the substrate, contributing to easier absorption of dyes into the fibre. A 45‐minute fixing process at 105°C by steaming delivered the best results of printing quality. Iron sulphate was used as the mordanting agent. The colour fastness to washing, dry and wet rubbing, and to light, was tested for samples with and without mordanting. The highest light and washing fastness were obtained with the iron sulphate mordanting agent printed in acid (pH 4) with paste containing 4% dry matter‐based thickener. The rubbing fastness was satisfactory for samples with iron sulphate printed with paste containing 4% dry matter thickener, fixed for 45 minutes, regardless of the pH.     

Cationic pretreatment of cotton fabric for anionic dye and pigment printing with better fastness properties

Improved printability with pigment and anionic dyes was obtained after simple cationisation of cotton fabrics with Solfix E. Different print paste formulations were used for printing cationised cotton fabrics with pigment, acid and direct dyes. Print pastes containing a synthetic thickener or a pigment emulsion showed good suitability for printing with pigment and pastes containing Meypro-gum as a thickener showed good printability with anionic dyes. The prints obtained on cationised cotton showed better overall fastness properties than prints obtained on untreated cotton. After repeated washings, the prints on cationised cotton showed a much smaller percentage colour loss than the prints on untreated cotton fabric.     

The study of colour fastness of commercial microencapsulated photoresponsive dye applied on cotton,cotton/polyester and polyester fabric using a pad‐dry‐cure process

Commercial microencapsulated photoresponsive dye was applied on cotton, polyester/cotton and polyester fabric using a pad‐dry‐cure process. Colour fastness of the photoresponsive fabrics to washing, wet cleaning, dry cleaning, rubbing and light was investigated. The CIELAB colour values of the fabrics before and after testing were measured using a reflectance spectrophotometer, and the colour differences were calculated to evaluate the fastness properties. The fabrics had better colour fastness to wet cleaning and washing than to dry cleaning. The fabrics showed higher colour fastness to wet than to dry rubbing. The photoresponsiveness of the fabrics decreased with prolonged exposure time to artificial light due to low photostability of the microcapsules.     

Digital printing of acrylic fabric with cationic dyes using conventional inkjet printer

A special printing ink formulation based on cationic dyes is developed for digital printing of acrylic fabrics using a conventional inkjet printer. In order to investigate the contribution of color gamut boundary of printer colorants to printing efficiency, customized color targets containing 3164 color patches in 25 different hues were generated. The printed color patches were then fixed through steaming for 30 minutes followed by washing with hot soap and water and finally drying. To show the influence of dye fixation on colorimetric changes as well as color gamut boundary of samples, the L*a*b* values of color patches before and after fixation process were compared. Results demonstrate that color saturation of samples is enhanced dramatically after the dye fixation process. In fact, 3D color gamut of color patches has been drastically expanded as a direct consequence of adsorption to absorption transition. Additionally, dye fixation changes the structure of printed image from halftone superimposed dots to contone superimposed dyes. Strictly speaking, during fixation process, colors inside the halftone dots diffuse through the interfacial area to make the individual printed dots integrated. This is in analogy to the chromogenic photography films and dye‐sublimation thermal transfer processes by which contone images are produced. Moreover, dye fixation improves the washing fastness of digitally printed acrylic fabrics to the level comparable with the traditional screen printing method. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 244–249, 2017     

The effect of ultraviolet‐curable water‐borne polyurethane acrylate binder concentration on the printing performance of synthetic leather

In this paper, synthetic leather samples were screen printed with pigmented pastes including two types of photoinitiators and three different concentrations of ultraviolet (UV)‐curable water‐borne polyurethane acrylate binder. The curing process was conducted under different combinations of lamps (gallium, mercury, gallium/mercury and gallium/gallium/mercury) at three power levels. Abrasion resistance, crock fastness, hardness and colour strength were investigated. Chemical changes in the clear and pigmented film structures because of UV curing were analysed by Fourier Transform‐infrared spectroscopy measurements. In hardness measurements, the highest hardness values were obtained with clear and pigmented formulations which have the highest solid content (57%). In colour measurements, higher K/S values were obtained in samples printed with the formulation having a binder concentration of 46%. Wet crock fastness values improved as the energy level increased during curing, and the highest values were obtained with a formulation which had a binder concentration of 57%. Greater amounts of binder in the formulations and increased amounts of energy applied to the surface during curing increased the hardness value of the prints, thus better abrasion resistance was obtained. Overall results suggested that the highest hardness, crock fastness and abrasion resistance values were obtained with the formulation with a binder concentration of 57%. However, for ease of application, printing efficiency and colour strength, the formulation with a binder concentration of 46% is recommended for printing, and curing under consecutive passes with gallium and mercury lamps at 120 W/cm is proposed in terms of energy efficiency and printing performance.     

Water-soluble cationic chitosan derivative to improve pigment-based inkjet printing and antibacterial properties for cellulose substrates

The water-soluble N-(2-hydroxy)propyl-3-trimethylammonium chitosan chloride (HTCC) was prepared by chitosan and glycidyl trimethyl ammonium chloride. Fourier-transform infrared spectroscopic analysis spectrum confirmed that glycidyl trimethyl ammonium chloride was grafted to the amino groups of chitosan via substitution reaction (Zhao et al., Int J Pharm 2010, 393, 268; Montazer and Afjeh, J Appl Polym Sci 2007, 103, 178). The obtained chitosan derivative was used to modify cotton fabrics for improving aqueous pigment-based inkjet printing and antibacterial properties. Scanning electron microscope images showed that HTCC was adhered onto the cotton fabrics surface and formed film structure. The K/S value on printed cotton substrates increased from 3.20 to 4.87, which indicated that higher color yield was achieved in this way. Modified samples performed better crocking fastness and laundering fastness than the control cotton fabrics. The line definition of modified cotton fabrics respectively, improved 16.5% and 12.6% in the warp and weft direction as the specified line width was 0.5 × 10³ μm. Samples also showed good antibacterial potential, the inhibitory rate for Staphylococcus aureus and Escherichia coli were both more than 95% when the concentration of HTCC used in the pretreatment solution was 0.8%. The antibacterial effect was found to be durable for 20 laundering cycles. However, the hand feeling of modified cotton fabrics presented a slight decrease. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Modelling the properties of pigment‐printed polypropylene nonwoven fabric using the Box–Behnken technique

The aim of this study was to develop statistical models for the effect of binder concentration and curing temperature and time on the air permeability, tear strength, tensile strength, and crocking fastness of pigment‐printed nonwoven polypropylene fabric. The design and analysis of the experimental work were carried out using Minitab ^® statistical software according to the Box–Behnken design of response surface methodology. Models were successfully developed. It was found that binder concentration improves the wet crocking and tensile strength while having a negative impact on all other responses. Increase in curing temperature and time affects the fabric tear strength negatively but has a positive effect on wet crocking fastness and fabric tensile strength. It could be concluded that pigment prints of good dry crocking fastness may be obtained on polypropylene nonwovens without deterioration in the mechanical strength and air permeability to a commercially unacceptable level. However, further work is required to improve the wet crocking fastness properties.     

Effect of some metal salt pretreatments on acrylic printing

Acrylic fabrics were pretreated with metal salts (aluminum sulfate, copper sulfate, ferrous sulfate, and potassium dichromate) in different concentrations. The tensile strength, elongation, and moisture regain of pretreated and untreated samples were examined. The effects of various concentrations of the metal salts, the pH of the printing paste, and the thickening agent on the color strength and fastness properties of the printed fabrics were studied to determine the optimum printing conditions. The pretreatment improved the printability of acrylic modified with a cationic dye and the fastness properties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 130–134, 2004