Use of a predictive colour model for managing the colour appearance of two‐colour woven fabrics

The aim of this study was to implement a two‐dimensional colour appearance model for prediction of the colour values of weft threads when the optical mixing of a two‐colour woven structure had to match the colour appearance of a single‐colour reference woven fabric. Five single‐colour woven fabrics were woven from five threads of similar hue. One of the samples was chosen as a reference, for which the colour appearance was the goal to be achieved in the two‐colour woven fabrics prepared with the other available warp threads and newly dyed weft threads. The colour values of dyed weft threads were predicted by a two‐dimensional colour appearance model. With dyed weft threads, managing the colour appearance of the two‐colour woven fabric was enabled to achieve the colour values of the reference. In the results, colour deviations between the predicted and measured colour values of weft threads revealed some limitations to the colour appearance model and performance of the dyeing process. After the production of the two‐colour woven fabric, the colour appearance matched the appearance of the reference, resulting in deviations of ΔE_CMC(2:1) = 1.2‐7.8. Moreover, the differences between theoretically predicted and measured colour values of the two‐colour woven fabric were evaluated as small, ranging from ΔE_CMC(2:1) = 1.5‐1.9. The results demonstrated the efficiency of implementing the colour appearance model and the dyeing process of weft threads as an approach to achieve the defined colour appearance of two‐colour woven fabrics, which with small colour deviations matches the colour of a single‐colour reference.     

A novel method for weft and warp yarn segmentation in multicolour yarn‐dyed fabric images

This paper proposes a novel method for segmentation of weft and warp yarns in multicolour yarn‐dyed fabric images. A multicolour yarn‐dyed fabric is cross‐woven by weft and warp yarns with different colours. When a multispectral imaging system is used to measure the colour of a multicolour yarn‐dyed fabric image, its weft and warp yarns need to be detected before analysing their colours. Detection of interstices between weft and warp yarns is firstly conducted. A modified K‐means clustering approach is then utilised to separate weft and warp yarns. The number of clusters is fixed to 2. The metric to measure the distance between a pixel and the mean of a cluster is the CIELAB colour difference. The initial means are determined by the expected values of fitted Gaussian distributions to CIExyY colour histograms. Experimental results show that the proposed method is promising for the segmentation of weft and warp yarns in multicolour yarn‐dyed fabrics, with an improved segmentation accuracy and much faster processing speed than K‐means clustering in CIEXYZ and CIELAB spaces.     

Automatic detection of layout of color yarns of yarn‐dyed fabric. Part 1: Single‐system‐mélange color fabrics

To recognize the layout of color yarns of single‐system‐mélange color fabric automatically, a novel FCM‐based stepwise classification method is proposed in this article. This method consists of three main steps: (1) warp yarn segmentation, (2) weft color recognition, and (3) the layout of color warps recognition. In the first step, the yarn segmentation method based on mathematical statistics of subimages is adopted to localize warp yarns preliminarily; and then the segmentation results of warp yarn are corrected by misrecognized‐boundary remove and missing‐boundary interpolation. In the second step, the weft color is extracted based on RGB color histograms of whole fabric image. In the third step, the pixels in each warp yarn are classified into two clusters by fuzzy C‐means clustering (FCM) algorithm in CIELAB color model separately, and the preliminary recognized layout of color warps is obtained. All warp colors are clustered by FCM algorithm in CIELAB color model again and the precise layout of color warps is output. The experimental and theoretical analysis proved that the proposed method can recognize the layout of color yarns of single‐system‐ mélange color fabrics with satisfactory accuracy and good robustness. © 2015 Wiley Periodicals, Inc. Col Res Appl, 40, 626–636, 2015     

Automatic detection of layout of color yarns of yarn‐dyed fabric. Part 2: Region segmentation of double‐system‐Mélange color fabric

To detect the layout of color yarns automatically, a novel projection‐based fabric segmentation method is proposed to segment the double‐system‐mélange color fabric into several regions, which can be seen as single‐system‐mélange color fabrics. This method consists of five main steps: (1) yarn skew detection, (2) fabric image projecting, (3) projection curve smoothing, (4) variance curve calculating, and (5) curve peak confirmation. Based on the acquisition fabric image, the skew angles of warp and weft yarns are detected by Hough transform first. The projection curves of L, a, and b channels in Lab color model are generated and smoothed by Savitzky–Golay filter. The variance curves of L, a, and b are then calculated, and the peaks corresponding to the regional boundaries in each curve are detected. The regional boundaries are confirmed by synthesizing the curve peaks of L, a, and b. The experimental and theoretical analysis proves that the proposed method can segment the double‐system‐mélange color fabric into regions with satisfactory accuracy and good robustness. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 626–635, 2016     

渐变系列色织床上用品面料的设计与织造

以25 tex×2涤纶纱为原料,采用联合组织、平纹组织、缎纹组织,织物经纬密度均为273根/10 cm、经纬紧度均为50%,结合色彩流行趋势进行色彩设计,并通过CAD模拟、小样织机织造,设计并织造出黄色渐变、红色渐变、蓝紫渐变、沙滩渐变4种床上用品面料。设计织造的4种面料都具有良好的视觉效果和手感,满足了床上用品面料舒适美观的要求。     

Color appearance modeling of bicolor striped woven fabrics considering neighboring color effects

In this article, the effect of the spatial and colorimetric attributes of neighboring color on color appearance shift in bicolor striped woven fabrics is investigated. A total of 240 test/neighboring woven color combinations were constructed in four different striped paradigms. Each test color in the combinations was visually assessed by 12 observer panels with the use of the magnitude estimation method estimating the magnitude of perceptual color attributes lightness, colorfulness, and hue. The visual estimates obtained were analyzed statistically by employing correlation and simple regression methods, and, as a result, the following significant neighboring color effects were detected and individually defined: (1) neighboring color's size, lightness, colorfulness, and hue on test color's lightness, (2) neighboring color's colorfulness and hue on test color's colorfulness, and (3) neighboring color's hue on test color's hue. Furthermore, through multiple regression analysis, color appearance models by which the lightness, colorfulness, and hue of bicolor woven fabrics can be predicted were derived. The predictive performance of the models was evaluated by calculating the difference between the visually estimated and the predicted color appearances, using ΔL*, ΔC*, Δh°, and ΔE_CMC(2:1). Among all the derived models, the model producing the smallest mean error was chosen as a final model, and its great accuracy in color appearance predictions was verified through further statistical evaluation. It is envisaged that the findings of this research are of benefit to design textile products with bicolor striped woven fabrics to have desired color appearances. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 512–521, 2017     

Bonding in fabric-cement systems: Effects of fabrication methods

This paper compares the effects on the bond between fabric and cement matrix of three different processing methods: casting, pultrusion and vacuum condition. The fabrics included bonded glass mesh, woven polyvinylalcohol, and warp knitted weft insertion polypropylene. Pullout tests were performed to examine the bond between fabric and cement matrix. A microstructural analysis was conducted and correlated with pullout data. Improved bonding was obtained for fabric-cement composites produced with the pultrusion process, particularly for fabrics composed of multifilament yarns that have open junction points and no sizing to seal individual yarns. This improved bonding results from the impregnation of the fabric in the cement chamber during the pultrusion process, which filled the spaces between the filaments of the multifilament yarns.     

Color prediction models for digital Jacquard woven fabrics

The current industry practice for producing jacquard fabrics uses computer‐aided design (CAD) systems that provide visual simulations of the final color appearance of actual fabrics prior to production. This digital process is fundamentally based on the prediction of combined weave‐color effects, which can be successfully achieved by accurate color mixing models and the structural details of the fabrics. With the accurate models used in CAD systems, designers would see simulations more closely resembling fabrics to be produced. By checking the previews, the designers can easily modify, that is, recolor, the designs on the display monitor without doing repetitive physical sampling with the adjustment of the weaves and the yarn colors. However, there is no ready applicable accurate color mixing model for woven structures and there has not been sufficient investigation of the color prediction despite its usefulness for the current digital CAD process. Our study investigated the, color prediction of jacquard woven fabrics designed based on the principle of optically subtractive color mixing with the use of CMY colors. The color prediction was firstly done through the application of the six color mixing models previously developed for various other applications including fiber blending and printing. The performance of each model was evaluated by calculating the difference between the predicted and the measured colorimetric data, using ΔE_CMC(2:1). The average color difference from the models was 11.93 ΔE_CMC(2:1), which is hardly acceptable in textile industry. In order to increase the accuracy in color prediction, the six models were then optimized. As a result, substantial improvements for all models were obtained with a decrease in color difference to 4.83 ΔE_CMC(2:1) on average after the optimizations. Among the six optimized color mixing models, the optimized Warburton‐Oliver model, that is, W‐O model, was found to have the lowest average ΔE_CMC(2:1) value of approximately equaling to 2, which is considered potentially useful to be applied to the current digital fabric color prediction. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 64–71, 2016     

Automatic detection of layout of color yarns of yarn‐dyed fabric. Part 3: Double‐system‐Mélange color fabrics

Automat layout detection of color yarns is necessary for weaving and producing processes of yarn‐dyed fabrics. This study presents a novel approach to inspect the layout of color yarns of double‐system‐mélange color fabrics automatically, which is Part III of the series of studies to develop a computer vision‐based system for automatic inspection of color yarn layout for yarn‐dyed fabrics. The inspection of single‐system‐mélange color fabrics has been realized in Part I of the series of studies. Integrating the projection‐based region segmentation method proposed in Part I and the FCM‐based stepwise classification method proposed in Part II, the proposed approach is composed of three steps: (1) fabric region segmentation, (2) fabric region selection, and (3) layout of color yarns recognition. In the first step, the fabric regions are segmented by the projection‐based region segmentation method. In the second step, the reasonable fabric regions are selected by analyzing their color histograms and comparing their weft color's frequency. In the third step, the layout of color yarn is recognized by the FCM‐based stepwise classification method, and the precise layouts of color warps and wefts are produced. The experimental analysis proved that the proposed method can recognize the layout of color yarns of double‐system‐mélange color fabrics correctly by testing four different color fabrics and three pieces of same yarn‐dyed fabrics. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 250–260, 2017     

Towards automation of color/weave selection in Jacquard design: Model verification

Jacquard woven fabrics are made from colored yarns and different weaves for designing complex pictorial and other patterning effects. The final visualized color effect is the result of assigning weave designs to different areas of the pattern to be created. The current practice in creating Jacquard woven fabric designs is to produce many samples in a trial‐and‐error attempt to match artwork colors. An ability to simulate accurately the appearance of a design prior to manufacture is highly desirable to reduce trial‐and‐error sample production. No automated accurate digital color methodology is yet available to assist designers in matching the patterned woven fabric to the desired artwork. To achieve this, we developed a geometrical model to predict the color contribution of each yarn on the face of the fabric. The geometrical model combined with a Kubelka‐Munk based color mixing model allowed the prediction of the reflectance properties of the final color for a given design. We compared the predicted and experimental values of the reflectance properties for a range of fabrics using the same geometric model with three separate color mixing models. The geometrical model combined with a log‐based color mixing model produced reasonable agreement between predicted and measured ΔE_ab, with an average ΔE_ab of approximately five. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 225–232, 2009     

Use of regression methods for determining the relation between theoretical–linear and spectrophotometrical colour values of bicolour woven structures

In this paper, new approaches for evaluating the entire colour effect of optical mixing of bicolour woven structures are presented. Simple woven structures with constant colour in the warp direction and different colours in the weft direction were prepared and analysed. The constructional parameters of these woven fabrics were systematically changed, which resulted in the variations of the fractions of colour components and, consequently, also in the changes of colour properties (lightness, hue, chroma) of bicolour optical mixtures. The position of colours of the bicolour structures and the approximate direction (linear) of colour changes in CIELAB colour space were theoretically determined with a simple geometrical model and additive method. Furthermore, the bicolour optical effects were determined spectrophotometrically. The differences between the linear–theoretical and the spectrophotometrical colour values of bicolour woven fabrics were mathematically analysed with linear and non‐linear regression methods to determine the positions of colour coordinates L*, a* and b* of bicolour woven fabrics in the a*b* plane by increasing or reducing the cover factors of warp and weft threads (addition or reduction of colour components). The results present, on the one hand, the strong influence of original colours of warp and weft threads and, on the other hand, the minor influence of constructional parameters on the form of linear/non‐linear behaviour of colours of bicolour compositions. When the characteristics of a specific colour combination are taken into account, the spectrophotometrical colour values of bicolour woven fabrics can be also mathematically determined with additive–theoretical colour values and, to some extent, with predictable colour deviations.     

Modifying of Cotton Fabric Surface with Nano-ZnO Multilayer Films by Layer-by-Layer Deposition Method

ZnO nanoparticle–based multilayer nanocomposite films were fabricated on cationized woven cotton fabrics via layer-by-layer molecular self-assembly technique. For cationic surface charge, cotton fabrics were pretreated with 2,3-epoxypropyltrimethylammonium chloride (EP3MAC) by pad-batch method. XPS and SEM were used to examine the deposited nano-ZnO multilayer films on the cotton fabrics. The nano-ZnO films deposited on cotton fabrics exhibited excellent antimicrobial activity against Staphylococcus aureus bacteria. The results also showed that the coated fabrics with nano-ZnO multilayer films enhanced the protection of cotton fabrics from UV radiation. Physical tests (tensile strength of weft and warp yarns, air permeability and whiteness values) were performed on the fabrics before and after the treatment with ZnO nanoparticles to evaluate the effect of layer-by-layer (LbL) process on cotton fabrics properties.     

三维正交机织物组织结构的几何表征和数学表征

切取三维正交机织物沿经向和纬向的连续横截面,在三维视频显微镜下拍摄和分析织物横截面中经纱、纬纱和Z纱的横截面形态、纱线空间构型,用参数方程表征理想状态下织物中经纱、纬纱和Z纱截面尺寸及屈曲形态。基于三维绘图软件Pro/E,重构三维正交机织物单胞模型及大尺寸织物模型,使其能更准确、更真实地反映三维正交机织物真实细观结构。     

Flammability behavior of fiber–fiber hybrid fabrics and composites

The effect of heat flux levels on burning behavior and heat transmission properties of hybrid fabrics and composites has been investigated using cone calorimeter and heat transmission techniques. The hybrid fabric structures woven out of E‐glass (warp) and polyether ether ketone (PEEK) (weft) and E‐glass (warp) and polyester (weft) have been studied at high heat flux levels keeping in view the flame retardant requirements of structural composites. The performance of the glass–PEEK fabric even at high heat flux levels of 75 kW/m² was comparable with the performance of glass–polyester fabric evaluated at 50 kW/m². The results further demonstrate that glass–PEEK hybrid fabrics exhibit low peak heat release rate, low heat release rate, low heat of combustion, suggesting an excellent combination of materials and fall under the low‐risk category and are comparable with the performance of carbon fiber‐epoxy‐based systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Three‐dimensional color prediction modeling of single‐ and double‐layered woven fabrics

In this research, the three‐dimensional structural and colorimetric modeling of three‐dimensional woven fabrics was conducted for accurate color predictions. One‐hundred forty single‐ and double‐layered woven samples in a wide range of colors were produced. With the consideration of their three‐dimensional structural parameters, three‐dimensional color prediction models, K/S‐, R‐, and L*a*b*‐based models, were developed through the optimization of previous two‐dimensional models which have been reported to be the three most accurate models for single‐layered woven structures. The accuracy of the new three‐dimensional models was evaluated by calculating the color differences ΔL*, ΔC*, Δh°, and ΔE_CMC(2:1) between the measured and the predicted colors of the samples, and then the error values were compared to those of the two‐dimensional models. As a result, there has been an overall improvement in color predictions of all models with a decrease in ΔE_CMC(2:1) from 10.30 to 5.25 units on average after the three‐dimensional modeling.     

Measuring linear density of threads in single‐system‐mélange color fabrics with FCM algorithm

According to the color yarns in the fabric, the fabrics can be divided into three categories: solid color fabrics, single‐system‐mélange color fabrics, and double‐system‐mélange color fabrics. The density of solid fabrics can be inspected with gray‐projection method or Fourier analysis method. But the methods cannot be applied to yarn‐dyed fabrics directly. A method for detecting the density of single‐system‐mélange color fabrics will be discussed in this article. By analyzing the pattern and color characters of single‐system‐mélange color fabrics, fuzzy C‐means algorithm is proposed to classify the colors in the fabric image based on CIELAB color space first. With the color segmentation results, the fabric can be divided into different blocks. The yarns can be located in different blocks with different average gray‐levels, and then the number of yarns can be counted in each block. The linear density of threads can be obtained by counting the yarns in a unit length finally. The experiment proved that the algorithm proposed in this study can inspect the density of single‐system‐mélange color fabric successfully. © 2012 Wiley Periodicals, Inc. Col Res Appl, 38, 456–462, 2013     

Fabrication and mechanical response of commingled GF/PET composites

The mechanical properties and the response to mechanical load of continuous glass fiber reinforced polyethylene terephthalate (GF/PET) laminates have been characterized. The laminates were manufactured by compression molding stacks of novel woven and warp knitted fabrics produced from commingled yarns. The laminate quality was examined by means of optical and scanning electron microscopy. Few voids were found and the laminate quality was good. Resin pockets occurred in the woven laminates, originating from the architecture of the woven fabric. The strength of the fiber/matrix interface was poor. Some problems were encountered while manufacturing the laminates. These led to fiber misalignment and consequently resulted in tensile mechanical properties that were slightly lower than expected. Flexural failures all initiated as a result of compression, and it is possible that the compression strength of the matrix material, rather than its tensile strength, might limit the ultimate mechanical performance of the composites. Flexural failures for both materials were very gradual. The warp knitted laminates were stronger and stiffer than the woven laminates. The impact behavior was also investigated; the woven laminates exhibited superior damage tolerance compared with the warp knitted laminates.     

GA747织机生产新型玻璃纤维纱罗网布的实践

新型玻璃纤维纱罗网布的地经和纬纱采用玻璃纤维无捻直接纱,绞经采用涤纶丝生产,取代传统网布使用的有捻纱线,并去除传统纺织中的整经工序,在GA747织机上安装绞综综框且采用合理的织造工艺,有效降低原料成本,提高产品品质。     

Development of an Automated Design Method for Manufacture of Fabrics of Defined Structure

An automated method of designing technology for manufacturing fabrics of defined structure was developed. An algorithm was developed for calculation of fabrics of defined structure in designing the technology, consisting of determining the properties of the fibres used (tensile and compressive viscoelastic parameters, durability parameters, resistance to wear and repeated loads, hemicyclic characteristics); determination of the coarse fabric structure phase; calculation of warp and weft tension during frontal battening based on use of the linear theory of warp thread fibre tension in the “warp roller—dropper” zone and the weft thread pinch tension based on the linear theory of viscoelasticity; estimation of the loom threading tension using long-term strength criteria; determination of the maximum possible rotation rate of the main loom shaft; calculation of breakage of warp and weft threads based on the assigned properties of the fibres. Software was created for designing loom manufacture. The manufacturing process for production of an important number of fabrics was designed. The basic process parameters for manufacturing fabrics were determined. __________ Translated from Khimicheskie Volokna, No. 5, pp. 35–40, September–October, 2005.     

Investigations on the level dyeing of fabrics in supercritical carbon dioxide

The level dyeing of fabrics in supercritical carbon dioxide was investigated by employing an improved beam (a perforated pipe on which the knitted or woven fabric/warp is wound around). The effects of system temperature, pressure, dyeing time, a time ratio of fluid circulation to static dyeing (R_time), different fabric layers wrapped around the beam, and the species and chemical structures of dyestuffs on leveling properties and color strength of polyester and cotton fabrics were observed. The results show that the leveling properties and color strength of fabrics were improved on the new beam, as well as with a favorably increased system temperature, pressure, dyeing time, and a time ratio of fluid circulation to static dyeing; while the leveling property and color strength decreased with fabric layers on the beam under an identical condition. Highly leveling results were obtained on polyester and cotton fabrics with disperse and reactive disperse dyes involving different chemical structures.