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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.

This study aims to evaluate the color accuracy of HP Jet Fusion 580 3D printing, comparing 3D-printed outcomes against original digital input colors.

A custom cyan, magenta, yellow and black (CMYK) and red, green, blue (RGB) color chart was applied to the top, bottom and side surfaces of a 3D model. Four of each model were 3D-printed on a HP Jet Fusion 580, and half the samples were finished with a cyanoacrylate gloss surface finish, while half were left in raw form. A spectrophotometer was used to document CIELAB (L*a*b*) data, and comparisons made to the original input colors, including calculation of ΔE.

The CMYK samples were significantly more accurate than RGB samples, and grayscale samples in both color spaces were the most accurate of all. Typically, CMYK swatches were darker than the input values, and gloss samples were consistently darker than raw samples. The chromaticity (a*b*) range was found to be significantly smaller than what can be achieved digitally, with highly saturated colors unable to be produced by the printer.

This is the first study, to the best of the authors’ knowledge, to characterize the full color spectrum possible with the HP Jet Fusion 580, recommending that designers use the CMYK color space when applying colors and textures to 3D models. A quick-reference color chart has been provided; however, it is recommended that future research focus on developing a color management profile to better map digital colors to the capabilities of the printer.

This paper aims to report on production of the colour digital printing toners cyan, magenta and yellow. Colour digital electrophotographic printing is currently in high demand. The provision of a large colour gamut depends on appropriate selection of precise colourants to produce toner capable of producing a thin layer on paper.

Printing toners were synthesised by the emulsion aggregation method, and then evaluated for chemical constitution and effects of the colourant substituents.

Results demonstrated that increasing the polarity of a pigment produced better dispersion and lower particle size with narrower distribution and even better colour reproduction. While, changing a pigment’s characteristics did not affect the toner shape or its thermal properties.

The developed method provides a simple way to synthesise colour printing toner.

Emulsion aggregation toners provide less hazardous materials during printing.

Evaluations of the influence of solid-state parameters and physicochemical properties of the pigments on printing toner characteristics were done for the first time.

This paper describes how the communication of colour specifications between designers and technical production personnel has been improved using calibrated colour and digital networking. The electronic colour communication system known as “Imagemaster”™ is described in which both colour and texture are quantified by calibrated variables. Colour is calibrated by reference to CIE colour co‐ordinates. Imagemaster also uses and if necessary generates a reflectance curve for each object on the screen for use as a production colour specification. A novel colorimetric model of textile textures based on image content is described, which can be used to predict the independent effect of texture as a distinct component of overall colour appearance. Close electronic collaboration between all those contributing to design, product development and production is described. Savings in the complexity, cost and lead‐time for achieving correct colour and technical specifications are reported.

The purpose of this paper is to address the key variables that determine the level of control of color in a typical textile supply chain, including lighting variability, color perception, and color measurement.

A fishbone diagram is used to demonstrate the wide range of variables that affect the control and communication of color within the textile supply chain.

It is important to identify the important parameters and variables that influence the control of color within various stages of the textile supply chain. In regard to visual assessment variability, the results obtained in an ongoing study at North Carolina State University based on the psychophysical testing of 50 observers demonstrate a statistical difference for visual judgments of small color differences between naïve and expert observers. Results of a paired t‐test between the second and the third trial conducted by naïve observers indicate that the repetition of the visual observations significantly affects the assessment of small color differences.

Assessment of lighting measurements of several stores in the USA demonstrate variability in lighting, with many stores having at least two different light sources. This variability, in combination with uncontrolled lighting from external windows and entrance/exit areas, can lead to significant variability in the color perception of textile garments displayed in such areas, and may lead to consumer experience being significantly different from that intended by the designer.

The optimization of variables that influence the assessment and communication of color is vital to achieving effective communication between all parties involved. This can significantly reduce costs and lead times resulting in improved competitiveness and cost efficiency associated with increased consumer satisfaction and confidence in the industry.

The repetition of visual observations significantly affects the assessment of small color differences.

Today, Jacquard woven fabric producers are able to digitally control each warp yarn individually, pre-program the variable pick density and speed for each filling yarn, and automatically change a pattern without stopping the weaving process. Jacquard CAD systems dramatically reduce the time to produce fabric from the artwork or target design The process of weave/color selection for each area of the pattern is, however, still highly dependent on the CAD system operator who works from a particular color gamut. Multiple weaving trials are required to get a sample that matches the original artwork since the process requires the designer‘s subjective evaluation. The lack of automatic selection of weaves/color matching prompts this research.

This paper addresses the development of a geometric model for predicting the color contribution of each warp and filling yarn on the fabric surface in terms of construction parameters. The combination of geometric modeling and existing color mixing equations enables the prediction of the final color of different areas of a Jacquard pattern. The model was verified experimentally and a close agreement was found between a color mixing equation and the experimental measurements.

THE Hastings Conference of the Library Association has come and gone, and the battle fought during the Annual General Meeting was in full keeping with the town's historical tradition. But whereas the defeat of Harold in 1066 led to a long era of stability in English history, the results of the A.G.M. vote last month will cause chaos and uncertainty in the immediate future of the Library Association. After protracted debate the Council's proposals for reorganisation went to the vote and gained a majority of very nearly 4 to 1. But just before the ballot it transpired that, at the request of the Privy Council, to which body the bye‐law alterations must be sent for approval, the votes of institutional delegates had to be counted separately from those of personal members. At the count, over 500 personal members voted for, with 35 against, but the institutional delegate vote was 135 for, with 141 against. So, for the present, all is uncertainty, and librarians everywhere will now await the Privy Council's decision with more than usual interest and impatience.

A disperse fluorescent yellow paste was mixed with a dispersant naphthalene sulfonic derivative via wet grinding process to prepare thermal transfer ink with good fluorescence. The paper aims to discuss these issues.

The surface tension, viscosity, pH value, zeta potential, stability and the morphology of ink samples were tested after the storing process.

The morphology of paste was homogeneous nearly spherical nanoparticles and the particle size was about 100 nm from the transmission electron microscopy (TEM), which was similar to the average particle size obtained from the particle size analyser.

The paste particle size was 126.8 nm after storing at 50°C for one week. The addition of diethylene glycol was conducive to high fluorescent reflectivity and gave good line image quality both in warp and weft directions due to the low viscosity. Inkjet printed polyester fabrics achieved excellent rubbing, laundering and thermal subliming fastnesses.

The polyester fabrics thermal transferred with the ink contained diethylene glycol represented higher fluorescent reflectivity and gave better line image quality both in warp and weft directions. The inkjet printed polyester fabrics showed excellent colour reproducibility and all the fastnesses, including rubbing, laundering and thermal subliming, were higher than Grade 4.

Communications regarding this column should be addressed to Mrs. Cheney, Peabody Library School, Nashville, Tenn. 37203. Mrs. Cheney does not sell the books listed here. They are available through normal trade sources. Mrs. Cheney, being a member of the editorial board of Pierian Press, will not review Pierian Press reference books in this column. Descriptions of Pierian Press reference books will be included elsewhere in this publication.