Visible‐near infrared concealment of cotton/nylon fabrics using colored pigments and multiwalled carbon nanotube particles (MWCNTs)

To match the reflectance profile of desert colors including dark brown, light brown and olive green in the visible‐near IR (Vis‐NIR) bands, five selected colored pigments were utilized to print woven cotton/nylon fabrics. Multi‐walled carbon nanotube particles (MWCNT's) were also added to some of the printing pastes. The reflectance of printed fabrics was evaluated by using spectrophotometric technique. The effect of adding MWCNT's, on washing; light and crocking fastness alongside with colorimetric values of printed samples was evaluated. Furthermore, the water absorption time was measured in order to determine wettability of each printed sample. The results demonstrated that the presence of MWCNT's in concentration range of 0.04–0.12 g kg^?1 in printing formulations was found to cause considerable decline in Near Infrared (NIR) reflectance while a surprising increase in visible reflectance of samples was observed. Color characteristics of printed fabrics were noticeably changed even at concentrations as low as 0.12 g kg^?1 MWCNTs in printing formulations. Presence of MWCNTs in printing formulations was found to cause a significant increase in wetting time of samples. Also, the results indicated that air permeability of printed samples containing MWCNT's were higher than samples printed with no MWCNTs. Phenomena imposed by MWCNT's presence on pigment printed samples showed very good fastness levels in crocking, washing and light fastness tests. In dark brown sample, adding MWCNTs to the pigment printing pastes could tune the overall reflectance in order to match the standard reflectance profile accepted for use in concealment color of desert areas. © 2013 Wiley Periodicals, Inc. Col Res Appl, 40, 93–98, 2015     

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 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.     

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.     

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.     

Sol-gel synthesis and characterizations of organically modified silica coatings on knitted cellulose for fixation applications

In order to improve the fixation properties, a novel organically modified silica coating (OMSC) was deposited on knitted cellulose fabric printed with pigment based ink. The organically modified silica sol (OMSS) was prepared by adding tetraethoxysilane (TEOS), γ-glycidoxypropyltrimethoxysilane (GPTMS), ethanol, H₂O and HCl. The color fastnesses of knitted fabrics treated with the OMSS were improved significantly. The coating treatment with OMSS (concentration 4-8 wt%) was beneficial to the washing fastness, and the fade rate of washing was reduced more than 50%. The dry and wet rubbing fastnesses were enhanced one or more grades. The scanning electron microscope (SEM) photographs of knitted cellulose fabrics indicated that continuous OMSCs were formed on the fiber surface, which contributed to the washing and rubbing fastnesses. The bending properties of fabric demonstrated that the fixing treatment had slight effect on the handle. These results suggest fixation with OMSS is an effective pathway to improve the color fastness of knitted cellulose fabrics.     

Pretreatment of wool/polyester blended fabrics to enhance titanium dioxide nanoparticle adsorption and self‐cleaning properties

This research aims to enhance the self‐cleaning properties of fibre‐blended fabric using surface pretreatment prior to the application of titanium dioxide nanoparticles. To this end, the polyester/wool fabric was modified, in that the wool fibres were oxidised with potassium permanganate and the polyester fibres were hydrolysed with lipase before nano processing. Butane tetracarboxylic acid was also used to enhance the adsorption of the nanoparticles and also to stabilise them on the fabric surface. The self‐cleaning properties of the fabric were examined through staining of the fabric with CI Basic Blue 9 and then discolouring by exposing to ultraviolet and daylight irradiation. Some other properties of the treated fabrics, such as water drop absorption, crease recovery angle and bending were investigated and are discussed in detail. The colour changes of different samples indicated an appropriate discoloration on the titanium dioxide‐treated fabrics after ultraviolet and daylight irradiation. Overall, the surface pretreatment of the wool and polyester fibres improved the self‐cleaning properties of the fabric significantly.     

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     

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.     

An innovative approach to the preparation of coloured and multifunctional silk material with the natural extracts from chestnut shell and black rice bran

In order to reutilise the byproducts of foods and crops to benefit the environment and economise on resources, the natural extracts from chestnut shell and black rice bran were applied in the simultaneous dyeing and multifunctionalisation of silk fabrics. In this work, the influence of pH value on dyeing properties was studied. The effects of the ratio of chestnut shell and black rice bran extracts and the application of mordants (aluminium potassium sulphate and ferrous sulphate) on the dyeing performance as well as anti-ultraviolet and antioxidant properties of treated silk were also discussed. The results showed that deep-coloured silk fabrics can be obtained when dyed with the two natural extracts as the pH value of the dyebath approached 3. The ratio of the two natural extracts and the use of the mordants have significant effects on colour depth, colour hue, colour fastness, and the functionalities of dyed silk fabrics. Combination dyeing and mordanting are able to enrich the colour hues of dyed fabrics. The washing, rubbing, and light fastness of the dyed fabrics after mordanting can be rated higher than grade 4. Moreover, the silk after combination dyeing has good UV protection performance (UPF > 30) and antioxidant activity. In addition, the functionalities of treated fabrics showed excellent washing fastness. This study reveals that chestnut shell and black rice bran extracts are suitable as natural colourants and multifunctional finishing agents for the preparation of coloured and multifunctional silk materials.     

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     

Preparation of melamine‐formaldehyde encapsulated fluorescent dye dispersion and its application to cotton fabric printing

In this study, CI Solvent Yellow 43 was encapsulated by melamine‐formaldehyde (MF) resin via in situ polymerisation to prepare the core‐shell structured fluorescent pigment. Fourier Transform‐infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis and differential scanning calorimetry were used to characterise the encapsulated CI Solvent Yellow 43, indicating that MF successfully encapsulated CI Solvent Yellow 43 and that a core‐shell structure was formed. The prepared MF encapsulated fluorescent dye dispersion was also applied to flat screen printing of cotton fabrics, and the colour properties and fastness properties (washing and rubbing fastness) of printed fabrics were studied. The results showed that the encapsulated CI Solvent Yellow 43 printed cotton fabric exhibited a higher chroma and fluorescence intensity than that printed with unencapsulated CI Solvent Yellow 43. Moreover, the washing and rubbing fastness of the encapsulated CI Solvent Yellow 43 printed fabric was improved.     

Chromic textiles: Colour fastness properties and irreversible colour change behaviour of textiles screen printed with thermochromic,photochromic and hydrochromic colourants

The objective of this work was to study how ultraviolet (UV) light exposure, washing and rubbing can influence colour and dynamic qualities of chromic textiles, and to explore how the results attained can be applied by designers for the development of colour changing palettes. The experimental work was conducted with 74% polyamide and 26% elastane elastics screen printed with thermochromic, photochromic and hydrochromic pigments in diverse colours. Initially, colourfastness properties of each pigment type versus colour were assessed. Although washing and rubbing can interfere in samples' colours by becoming lighter at different degrees, the results attained highlight the poor stability to lighting of thermochromic and photochromic pigments, which also present changes between hues along exposure time. For conventional textile applications, poor colour fastness commonly represents a limitation. This work proposes that the way textile colours and behaviour are permanently affected by the studied conditions can be interpreted as a creative variable in the design process. Research samples with a combination of pigments were developed and tested with a combination of cycles of different fastness tests, namely one washing cycle for every 4 h of UV light exposure, totalling 48 h and 12 washing cycles. Results demonstrate the possibility of creating interactive surfaces capable of displaying a wide range of colours that evolve to static within different hues, over stimuli conditions.     

Degree of crosslinking and physical properties of dimethyloldihydroxyethyleneurea/acrylic acid crosslinked cotton fabrics after treatment with various metallic salts

Three metallic salts were used to posttreat dimethyloldihydroxyethyleneurea (DMDHEU)/acrylic acid (AA) crosslinked cotton fabrics, and the results showed that at a given value of the tensile strength retention (TSR), the dry crease recovery angle (DCRA) and wet crease recovery angle (WCRA) of the crosslinked and posttreated fabrics were higher than those of the DMDHEU–AA‐treated fabrics, and those of the crosslinked and posttreated fabrics were in the order of Ag⁺ > Cu⁺² > Al⁺³. The DCRA and TSR values for the crosslinked and posttreated fabrics were higher than those for the DMDHEU–AA‐crosslinked fabrics, and those for the crosslinked and posttreated fabrics were in the order of Ag⁺ > Cu⁺² > Al⁺³; however, WCRA values for the crosslinked and posttreated fabrics were lower than those for the DMDHEU–AA‐crosslinked fabrics, and those for the crosslinked and posttreated fabrics were ranked as Ag⁺ > Cu⁺² > Al⁺³ at a given number of crosslinks per anhydroglucose unit. IR spectra clearly revealed the different interactions and bonding states between the hydroxyl group of the cellulose and the various metallic ions and the strength of the interaction. All crosslinked and posttreated fabric samples showed good odor absorption and antibacterial and washing‐fastness properties. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 584–594, 2005     

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.     

Plasma-induced adhesion improvement of cotton/polypropylene-laminated fabrics

In this study, improvement in the adhesion strength of plasma-pretreated and laminated cotton/polypropylene (PP) fabrics using acrylic-based adhesive was investigated. Low-temperature, low-pressure oxygen plasma was utilized for surface modification of cotton/PP-laminated fabrics. Water absorption time was measured on plasma-treated cotton fabrics at different plasma power and treatment time conditions. The plasma conditions providing the fastest liquid absorption on the surface were selected and applied during plasma pretreatments. Surface wettability increased with increasing plasma power and plasma exposure time. Plasma-induced surface morphology changes were observed via Scanning Electron Microscope (SEM) images. X-ray Photoelectron Spectroscopy (XPS) analysis showed that oxygen content on the surface increased with plasma treatment, which contributed to the surface polarity and hydrophilicity. Peel bond strength results of untreated and plasma-treated samples were analyzed to determine the effect of plasma pretreatment process. Adhesion strength values of laminated samples, before washing and after 40 wash cycles, were determined by peel bond strength tests. Before washing, adhesion strength of plasma pre-treated, laminated samples was 28–60% higher than that of untreated laminated fabrics. After 40 wash cycles, adhesion strength of plasma pre-treated and laminated samples was about 40–69% higher than the untreated laminated fabrics. Peel bond strength values decreased with the increased number of wash cycles. Plasma pretreatment enhanced both the adhesion strength and washing resistance of laminated samples.     

Application of polyurethane/citric acid/silicone softener composite on cotton/polyester knitted fabric producing durable soft and smooth surface

Application of softeners on fabrics can usually increase the fabric pilling tendency and it is difficult to obtain a soft handle fabric without pilling during wearing. This research was conducted to use various chemicals to reduce pilling with reasonable softness on the cotton/polyester knitted fabric. Diverse composites of the water‐based polyurethane resin (PU), citric acid (CA) as a crosslinking agent and silicone‐based softener were selected and applied on the fabric through conventional pad‐dry‐cure method. The characteristics of the treated fabrics including pilling rate, pilling density, water droplet adsorption time, bending length, crease recovery angle, tensile strength, and water contact angle were examined and reported. Application of the polyurethane resin along with citric acid reduced the fabric pilling. However, co‐application of resin, CA, and softener improved the fabric crease recovery angle, bending length, and water droplet adsorption time. The preferred formulation was 20 g L^?1 CA, 25 g L^?1PU resin, and 20 g L^?1 silicone softener. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

The surface polymerising of fluoromonomer and the shade-darkening effect on dyed polyester microfibre fabric

The surface polymerising of fluoromonomer on dyed polyester microfibre fabric is investigated. The shade-darkening effect of perfluoropolyester acrylate polymer is discussed by colour yield, reflectance spectrum and the colour differences. The surface polymerising of fluoromonomer on dyed polyester microfibre fabric had an excellent shade-darkening effect. After surface polymerising, the dyed fabrics had no significant effect on washing and wet rubbing fastness.     

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.     

Modelling the properties of pigment‐dyed polyester/cotton sheeting fabrics by response surface methodology

The aim of this study was to model the effect of pigment, binder and fixer concentrations on the rubbing fastness, crease recovery, tear strength and stiffness of pigment‐dyed polyester/cotton sheeting fabrics. The design and analysis of experiments were carried out using Minitab^® statistical software according to the central composite design of response surface methodology. It was found that an increase in the binder concentration significantly improves the dry rubbing fastness, crease recovery and stiffness of the fabric, with a corresponding decrease in fabric tear strength, without significantly affecting the wet rubbing fastness. An increase in the fixer concentration significantly improves both the dry and wet rubbing fastness and crease recovery, with a decrease in fabric tear strength and stiffness. The effect of binder and fixer concentrations on crease recovery was not linear and there was significant negative interaction between these factors for dry rubbing fastness. The effect of pigment concentration was not found to be statistically significant for the types and range of concentrations of pigment, binder and fixer used in this study.