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Woven and knitted polyester fabrics were pretreated with formulations containing waterborne UV curable resins and silica particles to improve inkjet print quality. The selected formulations were applied with low add-on to reduce the adverse effect on fabric hand without sacrificing the print quality. A print pattern with block areas and lines in cyan, magenta, yellow, and black colors was designed and inkjet printed on the pretreated fabrics with a wide-format inkjet printer (Encad Novajet 750) to investigate the effects of the UV curable pretreatment on the inkjet print color qualities including color depth, color gamut and color lightness.

Experimental results show that both the color depth and gamut of prints on the pretreated taffeta and knitted polyester fabrics were enhanced compared to those on untreated polyester fabrics. However, both the color depth and gamut of the prints on the pretreated satin polyester fabrics were reduced. The lightness change of the inkjet printed colors on pretreated knitted fabrics is similar to that of untreated fabrics whereas the lightness change of prints on pretreated satin and taffeta fabrics shows some differences. All colors have increased lightness on pretreated satin fabrics. However, magenta and black have decreased lightness on the pretreated taffeta fabrics.

The purpose of this paper is to prepare anionically surface‐modified organic pigment/binder ink jet inks for printing on chitosan‐pre‐treated silk fabrics.

Anionically surface‐modified organic pigment/binder ink jet inks were prepared in four colours (cyan, magenta, yellow and black). The pigment‐to‐binder ratio was controlled at 1:6.4 for the cyan, magenta and yellow inks, and 1:3.4 for the black ink. Ink formulations (by weight) were assembled and mixed as follows: 8 per cent pigment dispersion, 10 per cent diethylene glycol, 12 per cent glycerol, 5 per cent urea, 10 per cent polyacrylate emulsion binder and 55 per cent deionised water. They were characterised in terms of their particle size, zeta‐potential, particle morphology, viscosity, surface tension and pH. The inks were printed onto silk or the chitosan pre‐treated silk fabrics using a piezo‐type ink jet printer. The fabrics were then heat cured and analysed for the effect of chitosan pre‐treatment on colour gamut, wash fastness and crock fastness.

The formulated ink jet inks yielded an acceptably good ink jetting reliability, one‐year stability and printability. The chitosan pre‐treated silk fabrics gave a wider colour gamut and colour saturation than the non‐treated one. Crock fastness and wash fastness of the chitosan pre‐treated fabrics were relatively better than those of non‐treated fabrics.

The surface‐modified pigments are transparent and thus their inks printed on the chitosan pre‐treated fabrics produced slightly low K/S values of cyan, magenta, yellow, and black colours because the limited chitosan concentration in the pre‐treatment is controlled by its solubility in acidic solution. The higher loading of chitosan pre‐treatment gave higher K/S values and a stiffer touch of the fabrics.

The water‐based pigmented inks having the sulphonate group on the pigment surface can be printed on the fabric surface pre‐treated with chitosan molecules which have the protonated amino groups to give good colour appearance. It is anticipated that this type of ink can be applied to any textile surface which has been pre‐treated with the protonated chitosan.

The modified organic pigments having the sulphonate group on their surface can be used to produce novel water‐based ink jet inks which can print on the chitosan pre‐treated silk fabric. Ionic interactions between the sulphonate group of the pigment and protonated amino groups of chitosan in conjunction with polyacrylate binder enhance colour strength, widen colour gamut and chroma, and produce good adhesion for fabric operational properties such as wash fastness and crock fastness.

The purpose of this paper is provide a broad view for the standardization efforts of color quality evaluation of color 3D printing techniques. Further, this review paper demonstrates the processes and color properties of most color 3D printing techniques with specific devices and applications to extend the range of possible memberships of standardization group.

Six color 3D printing techniques including plastic-based, paper-based, powder-based, organism-based, food-based and metal-based color 3D printing have been introduced and illustrated with colorization principles and forming features in detail. Moreover, for printed 3D color objects, literature about color measurement, color specification and color reproduction are described and analyzed, respectively.

Four color 3D printing techniques including plastic-based, paper-based, powder-based and food-based color 3D printing show great affinity toward standardization of color quality evaluation, while their colorization principles indicate that it is difficult with a single standard frame. It is possible to develop a completed color quality evaluation standard for color 3D printing based on approaches in color 2D printing when color measurement method and devices are standardized together.

The paper provides an important guide focusing on the efforts to standardize the colorization processes and color quality evaluation of the color 3D printing techniques.

Camera‐based colour measurement systems have application where it is difficult to apply a contact instrument, or where the contact instrument, because of its fixed lighting geometry, does not provide the necessary data. The paper describes the principles, procedures and precautions necessary for camera based colorimetry. Equations are presented to convert digitised R G and B values, which are system specific, into CIE X Y Z colour values, an international standard method of colour specification. It is reported that colours spaced equally in RGB values appear to have visual colour difference steps varying in size by as much as 30:1 through the different regions. The poorest colour resolution occurs for RGB values that represent dark or strongly coloured shades. At least ten bits per channel digitisation of RGB values is required to achieve a colour resolution similar to the human visual system for dark, intense shades.

The reflectance spectra of natural and man‐made surfaces are highly constrained. Statistical analyses have been conducted that confirm that the surface reflectance spectra form a set of band‐limited functions with a frequency limit of approximately 0.02 cycles/nm. The reflectance spectra can be represented by a linear‐model framework and are adequately described by 6‐12 basis functions. However, the spectral properties of surfaces are not so constrained as to allow the human visual system to recover the surface properties from cone excitations. Furthermore, trichromatic colour devices such as scanners and cameras can only capture illumination‐specific colour information.

This paper aims to present a method of color three-dimensional (3D) printing based on color adherence.

First, experiments of the color effects of 3D printings using different carriers and different printing methods were performed. Second, the color of a specific point could be calculated through a theory of dimension-reducing, and the color distribution of 3D model was transformed from 3D to 1D color line corresponding with 3D print sequence. At last, the color lines, which were printed on a PE film by silk-screen printing, was carried by a filament and then printed through a fused deposition modeling 3D printer.

The printing ink and PE film are suitable as the pigment and carrier under this investigation, respectively. Based on an idea of reducing dimension, the method of 3D color printing through adhering color to a filament is realized. The color saturation of the sample was relatively high through the method.

It is hard to avoid that there may be some residual color in the nozzle through this method, and the purity of following color will be affected. As a result, continuous improvements should be made to perfect the method.

An approach of 3D color printing is described in detail, and what kind of model is more applicable is discussed particularly.

This approach is implemented to print color 3D objects with just one nozzle by means of color adherence. That is, printing the 3D objects using the filament is carried out with 1D color line, which is printed by a traditional printing method.

Compares Coldset and Heatset lithographic processes and shows why Heatset dominates the market for the production of supplement inserts and promotional articles for the news industry. Discusses the progress that has been made in a collaborative project to improve the performance of the Coldset process. States that further progress is required to make Coldset truly competitive with Heatset.

This paper will review digital ink‐jet printing on textiles and the advantages it offers to textile industry and consumers in comparison with conventional printing. The paper also reports on some of the results of a large project, which has been undertaken in the University of Leeds to address a number of issues concerning the problems associated with this technique. One of the important issues associated with digital ink‐jet printing on textiles is speed and reliability, as this has commercial implications for the industry. The research carried out in Leeds has addressed this problem and solutions are proposed which will be covered in detail in this paper. Further research has also been carried out to establish the issues surrounding digital ink‐jet printing and print quality when different types of designs are being printed. The paper will address the results of this research on quality assessment of digital ink‐jet printing on textiles.

In nature, thousands of different colours and shades exist. Basic set of dyes, namely, yellow, red, blue and green are necessary for a complete colour gamut. Creating a complete gamut with natural dyes with one common extraction and application procedure is not exploited hitherto. The paper aims to discuss this issue.

In this study, an attempt was made to create a complete colour gamut with easily available natural dyes with one common extraction and application procedure.

Silk fabrics were dyed using various natural dyes alone and in combination to yield various shades, namely, yellow, red, green, blue. Pre-mordanting of silk fabrics was carried out with mordants, namely, alum, ferrous sulphate, copper sulphate, stannous chloride, potassium dichromate followed by dyeing. The fastness properties and colour strength values of all the shades obtained were determined.

Creating a complete gamut with natural dyes with one common extraction and application procedure is not exploited hitherto.

The purpose of this paper is to reveal the potential use of faba bean husk as natural dye, to create a color gamut and to observe the effect of different mordants. Dyeing properties of polyamide/elastane fabric using faba been husk were investigated. The effect of alum [KAl(SO₄)₂], iron II sulfate Fe(SO₄)7H₂O, tin II chloride (SnCI₂2H₂O), copper II sulfate (CuSO₄), citric acid (C₆H₈O₇), tartaric acid (C₄H₆O₆), oxalic acid (H₂C₂O₄), ammonium sulfate [(NH₄)₂SO₄], sodium acetate (C₂H₃NaO₂), combination of alum-iron, iron-tin and alum-tin were evaluated in terms of color yield, color coordinates and wash fastness.

Mainly, dyeings were conducted in accordance with a simultaneous mordanting method. However, pre-mordanted dyeings were also implemented with selected concentration (0.8 g/L) of metallic mordants to enrich color gamut. Control sample (without mordant) was used as a reference for examining the effect of different mordants. Dyed samples were compared mutually in the light of visual evaluation and color measurements and alternatives to metallic mordants were also assessed.

Significant differences occurred in color coordinates of dyed samples. The biggest color difference and completely different color shades were achieved with tin II chloride. The type of acid did not create visible color differences. As alternatives to metallic mordants; all of them may be used instead of alum (0.8 g/L). Tartaric acid and oxalic acid, instead of iron II sulfate (0.2 g/L), and ammonium sulfate (0.2 g/L) and sodium acetate (0.8 g/L), instead of alum (0.8 g/L), can be used. Sodium acetate cannot be replaced with iron. A combination of alum-iron and iron-tin can be the alternative to 0.2 and 0.8 g/L copper, respectively. All the samples provided good wash fastness (4/5) values.

Valorization of industrial, agricultural and domestic wastes as novel natural dye sources is an ecological and sustainable approach. Moreover, the use of man-made fibers in natural dyeing is an issue that needs to be developed and expanded. Few literatures have been found concerning the use of husks of faba bean as a natural colorant. In this initial study, husks of faba been as a vegetable waste were utilized in natural dyeing of polyamide/elastane fabric. It is suggested that this waste can be turned into an economic value through its valorization in natural dyeing.