Quality Of Digital Printing Research Articles

Дослідження якості цифрового друку на бавовняній тканині

Дослідження якості цифрового друку на бавовняній тканині

Digital Printing Quality Detection and Analysis Technology Based on CCD

With the help of CCD digital printing quality detection and analysis technology, it can carry out rapid evaluation and objective detection of printing quality, and can play a certain control effect on printing quality. It can be said CDD digital printing quality testing and analysis of the rational application of technology, its digital printing and printing materials for a variety of printing equipments to improve the quality of a very positive role. In this paper, we do an in-depth study and discussion based on the CCD digital print quality testing and analysis technology.

The effect of fabric density on the quality of digital printing on polyester

One of the most important benefits of textile inkjet printing is the print quality. However, some factors affect the print quality, such as the weave density. In this research, the effect of weft density on the inkjet printing of polyester was investigated. Lines with different widths were printed in the warp and weft directions, and the print quality was evaluated as the line width. The obtained result showed that the weft density affected the line width and the print quality decreased with an increased weft density. The width of the lines printed in the weft direction is more than the width of lines printed in the warp direction. Also, the analysis of variance (ANOVA) results confirmed the effect of the weft density and the printed lines direction on the line width and print quality. The investigation of the relation between the print quality and the vertical wicking shows a very poor relation between the two.

Influence of paper surface characteristics on digital printing quality

Today’s demands for high quality digital printing emphasise the importance of paper surface. This work demonstrates the effects of surface topography and appearance on printing quality. Samples were printed in black and white with a laser jet printer under identical conditions, using different types of paper in order to have different surface properties. The papers and printed samples were evaluated with atomic force microscopy (AFM), scanning electron microscopy (SEM), gloss meter, spectrophotometer, and densitometer. Results showed that the decrease in surface roughness increased optical density and print quality. Moreover, the gloss of the papers significantly influenced print quality by decreasing it. The effect of the colourimetric values of the papers on the colourimetric values of the final printed samples were less significant in higher optical density printed samples.

The Study in the Application of Nanotechnology Digital Printing in Clothing Pattern Design

Nanotechnology, in the 21st century, is the biggest driving force in the development of technology and industry, which has its wide range of applications. In traditional industries, nanotechnology can be applied to the development of digital printing ink. Digital printing appears as a new printing technology in the 1990s, the 20th century. And in recent years, along with the trends of a global energy saving and carbon reduction, the concept of producing green products with low-carbon, water saving, energy abating, pollution decreasing attributes has arisen. The introduction of digital printing to textiles brings the speed, flexibility, wide areas of color selection, environmental protection and the potential of cost saving etc; the technology becomes a major breakthrough in the textile printing industry. The industry is committed to the technology of environmental friendly digital printing and goes toward to a new pattern of bright future in fashion design. While the globe puts effort to develop digital printing, the core technology should not only focuses on how to come up with high-speed, large amount, low-cost machines, but also the R & D to the making and applications of digital printing, which has a great impact on digital printing quality. At the present, the digital printing ink of the reactive ink / acidic ink is applied to cotton fabrics and the fabrics containing hemp content. The printing process is from the fabric pretreatment → inkjet printing →solid color processing → washing → drying. Moreover, sublimation transfer ink is applied to fabrics containing polyester fiber content; but it cannot be fully colored the fabrics of general 100% cotton and silk, which is the biggest drawback of this sublimation transfer ink. Therefore, this study, primarily through the Nanotechnology with green environmental protection and reduction of carbon from Mimaki Engineering Co., Ltd., captures the moral of the cultural patterns of the local characteristics by the techniques of changing, modeling, designing, and arranging on the patterns of dress design. And it uses computer graphics software, Adobe Photoshop & Illustrator, to draw and trim the separate pattern and the foursquare consecutive pattern for the completion of fashion pattern designs. And it applies the features of the nano pigment ink on the fabrics of cotton, hemp, silk, and polyester fiber to interpret the artistic style of the local through digitized programming language. The importing of nanotechnology refills new sources of industrial competition. This study expects to explore the nanotechnology digital printing and combine with the design of the clothing pattern transforming on the designs, grinding pigment molecules to nano ultra-fine level with reduced light scattering phenomena and good light purity. Fully demonstrating the features of natural bright color, the endurance of pigment water and the light fastness will be able to create a lager space of application and market in the digital printing industry.

Experimental Study of Digital Printing Methods for Producing Personalized Packaging

With the development of technologies in digital printing, variable data printing and on-demand printing for producing printing products with personalized information become more and more popular. The technologies make it possible to produce packaging for consumer products that contains personalized information that meets the special needs of individuals. There are two common approaches to produce personalized packaging. One approach is a hybrid process, which adds personalized information by inkjet printing or toner press onto the packaging that is printed primarily by traditional printing methods. This requires the digitally printed colors to match the colors printed by traditional printing methods. Another approach is to print the packaging completely by digital printing. Most commonly, toner-based laser printing is the first option for lower weighted paperboards. This approach is often limited by the print quality of laser printing. This study focused on experimental study on the quality of digital printing for producing personalized packaging. The parameters investigated are color gamut, resolution of lines and fonts. The print quality of digitally printed packaging was compared to traditional packaging producing methods, such as lithography printing, flexography printing, and gravure printing.

Effect of Instrument Precision on Area Quality Measurement Used in Digital Printing Quality Assessment

In this study the effect on quality measurement introduced by input precision of instrument in image digitizing process was verified through a series experiment. Two categories of samples, which were outputted by EPSON Stylus Pro7880c digital inkjet printer and Xerox DocuColor5000 digital xerographic printer individually, were transformed into digital image with a normal flatbed scanner in 600 DPI, 1200 DPI and 1600DPI resolution. The area quality attributes such as graininess, mottle, NPS and banding were surveyed and analyzed with the aid of PIAS™-II personal image analysis software to investigate the stability of normal instrument used in digital prints measurement system. Results show that precision demands are different for various quality parameters and different application backgrounds, namely it is precise enough for common industry detection which has lager tolerance, but higher resolution does good to more effective and more precise measurement especially in R&D.

The Influence of Paper Factors on Digital Printing Quality

Digital printing has been playing a more and more important role in printing industry for its convenient production and quick turnaround. By experimental method, the differences of digital prints with different paper were detail analyzed, includes different base weight papers of the same category, and different categories papers with the same base weight. Results showed that the printing quality of offset paper with 120 g/m2base weight was better than that of 100 g/m2, and that printing quality of art paper was better than matt art paper with the same base weight. Other characteristics of different papers were investigated too. The method and conclusion provides in this paper would be helpful for choosing appropriate material for production activities.

A Productivity Study of Digital Printing in the Packaging Industry

SUMMARYIn this study, the suitability of digital printing is evaluated in short runs in packaging industry. The image quality of digital printing is high enough to be used in packaging. The advantages of digital printing and modern converting processes include e.g. the possibilities of using variable data, on‐demand manufacturing and cost‐effectiveness within short print runs. The limitations may include a smaller colour gamut compared to traditional presses, format size, productivity and lower printing speed. In addition, the variety of substrates for use is smaller than in traditional printing.The productivity of the world's first integrated digital printing line designed for short runs was tested by simulating various packaging runs in production. For further analysis, an MS Excel calculation tool was developed. In the calculations, the productivity of a digital packaging line was compared with that of a standard packaging line based on an offline offset printing technique. The cost advantages to be achieved by digital printing techniques in short runs are discussed in two scenarios. The scenarios address the subjects' break‐even point and inline production process.The results of the study show that it is possible to achieve significant cost savings using the inline digital printing and converting systems when compared with traditional offline manufacturing systems in short runs. However, as there are numerous variables included to the production process, it is impossible to present any exact numbers for the break‐even point. In this study, the break‐even point calculated is estimated to be in the range of 4000–8000 packages, depending on the package and sheet sizes. The greatest difference in price per package occurs when the runs are below 2000 packages. Based on the calculations, the inline process itself can decrease the payback time for the machine line as much as 20–35%.One significant factor to be mindful of is that when digital printing is used in the short runs, it often releases machine time from the traditional presses. This part of the analysis has not been included in this study, but using the calculation tool, it is easy to simulate different scenarios and perform further analyses on the systems. Copyright © 2011 John Wiley & Sons, Ltd.

Study on the Influence of Coated Paper's Performance on the Printing Quality of HP Indigo Digital Printer

In order to improve printing quality, the relationships between paper's performance and the quality of digital printing are studied; coated papers with different grams and manufacturers are chosen, the smoothness, roughness, tightness, K&N value and gloss of the paper respectively are tested. Printing proofs by the HP indigo 1050 digital printer, solid density and dot gain of the printing proofs are tested. Mathematical processing method of statistics regression analysis is used for analyzing the relationships between paper's performance and the quality of digital printing. The results show that the influence of tightness and K&N value to the quality of digital printing is the most remarkable, while the influence of roughness is relatively remarkable.

Improvement of the Quality of Digital Printing Using Conditional Halftoning Function

Printed images usually suffer to halftone dot contacts and thus lose their tone details where that contact takes place. Dot contacts should be avoided by means of certain technical approaches as early as image processing stages. This paper begins with the mathematical analysis of the mechanism of dot contact regarding different dot shapes of round, square and diamond. Then experiments were carried out to verify theoretical results derived through outputting single-color chips (20 mm×20 mm) using HP indigo 3550 press with paralyzing its dot gain compensation function. Chips under research were designed with dot area percentages varying from 25% to 80%, and two levels of resolution (600 and 1200 dpi) were used respectively for each dot area percentage. The theoretical analysis showed that dot contacts happened in case of dot area percentage 78.5% for the round dots, 50% for the square dots, 35% (first contact) and 65% (second contact) for the diamond dots, respectively. Jumps in dot density were employed to determine whether the dot contact happened or not. It was observed that halftone dot contacts occurred at the dot area percentage 71% for the round dots, 47% for the square dots, 34% (first contact) and 62% (second contact) for the diamond dots, all lower than their corresponding theoretical values. A conditional halftoning function was designed on the basis of experimental results, which was programmed using the PostScript language. The averaged density difference tested at the 34% of dot area percentage was 0.026, 47% was 0.025, 62% was 0.034 and 71% was 0.041, where the normal halftoning technology was used. In contrast, the averaged density difference was reduced to 0.005 at the 34%, 0.012 at the 47%, 0.016 at the 62% and 0.019 at the 71%, in the case of using conditional halftoning function. These results indicate that the conditional halftoning function is useful for diminishing halftone dot contacts. This study provides a promising halftoning method to improve the quality of digital printing that is subject to the negative effect of halftone dot contacts.

Line Quality Analysis in Digital Printing

In this study, the line quality defects in digital printing will be evaluated and analyzed. The design of a line quality analysis system will be described in some detail. The attributes of line qualities have been defined in the ISO13660 standard. Among them, the line width, raggedness and blurriness are used to reflect the edge features of lines. The analysis of line quality can be applied to evaluate both text and line quality. Using carefully designed test targets, it can also be used to evaluate other printing problems like inter-color bleed, positional errors from a device, and color registration problems. By using digital printer with different imaging mechanisms or different types, the three attributes, line width, edge raggedness, and edge blurriness, which best present the digital printing quality, are measured and analyzed. The measurement of the line quality attributes is made through the line tool in analysis system. The evaluation and analysis of line quality in digital printing provides a basis to solve the line quality measurement in current digital prints, and offers a practical technology for quality controlling of digital prints.

The Printing Quality Control of HP Indigo Digital Printing Machine

In order to ensure printing quality of HP Indigo digital press 1050, the prints was printed on three kinds of paper through different compensation curves and changing developing drum voltage and laser energy value. With testing the solid ink density and dot area percentage of prints, the effects of these factors on digital printing quality were studied and two methods that adjusting dot area percentage were compared. The results indicate that different compensation curves have different effects on dot gain, the increase of developing drum voltage can improve solid density, and the increase of laser energy value can enlarge dot area percentage and the method using color control to adjust dot area percentage is more accurate than color match.

UV LED Curing in Inkjet Printing Applications

LEDs have many potential advantages as alternatives to traditional UV light sources for adhesive and ink curing. However, the application of LEDs for UV curing has not been as successful as expected by many researchers, despite the many attractive features LED technology provides. The high cost of UV LEDs is often cited as the primary reason for why they are not widely accepted in the industry.Based on our understanding of LED technology, we have compared the performance of LED based light sources with traditional UV light sources and addressed the technical issues such as spectrum and light intensity needed for UV curing applications.While much effort is still needed to successfully use LEDs in full-cure applications, recent work between EXFO and key digital print partners has shown that LEDs will improve the quality of digital printing. Print quality is controlled through an intermediate stage called ‘pinning’, where UV ink is partially cured on the print media. At this stage, LEDs have many advantages compared to traditional UV light sources. The improvements in print quality including enhanced image resolution, color depth and color clarity have been discussed.

Effects of Pretreatments on Print Qualities of Digital Textile Printing

Research presented in this paper addresses some preliminary attempts to establish the relationship between the pretreatment and the digital printing quality by the use of digital image analysis and optical microscopy. As in traditional textile printing, miss color, out of fit patterns, mottle, and color defects due to poor ink surface coverage can occur in digital printing. More specifically, defects in the digital printing of textile fabrics can be categorized into color-related issues (color gamut, color matching, light fastness, wash fastness and uniformity) and appearance-related issues (line definition, dot geometry, penetration, intensity and color registration). Woven and knitted cotton fabrics were treated with twelve formulations including ingredients like alginate, silicone and silica. Printed patterns were analyzed using an optical microscope and a digital image analysis to quantify the print qualities in terms of color-related metrics (L*a*b*) and appearance-related metrics (line width). Results show that digital textile printing quality on cotton fabrics can be optimized with appropriate pretreatments.

Dry Toner Based Electrophotographic Printing of Extrusion Coated Packaging Boards

Digital printing is suitable for short runs of highly personated packagings. The obvious benefit of digital printing is low waste amount and print-on-demand. The status of digital printing, at least in packaging sector, is still quite moderate, but the future is bright and it has been estimated that this method will increase more than the traditional printing techniques. The quality of digital printing will also approach that of offset.The aim of this study was to evaluate printability of various extrusion coatings used for packaging boards and to map out important material and process parameters.