Development of mineral oil free offset printing ink using vegetable oil esters

Until the middle of this century, fats and oils are the major raw material source for paints, coating and lubricating applications. These markets are completely taken over by petroleum based stocks due to their abundance and versatility. However, recent public awareness to use environmentally acceptable products that minimize pollution, are compatible to human health and readily biodegradable created opportunities for vegetable oils for application in paints and printing inks. The formulation of vegetable oil methyl ester based 'green' offset printing ink that reduces the volatile organic compounds (VOC) has been discussed in the present study. Methyl esters of rapeseed, soybean, rice bran and palm oil have been prepared and their physical properties have been measured and compared with standard petroleum feed stock. Varnishes were prepared with these esters and their properties are also compared with that of the petroleum based products. Rheological properties of the inks are also evaluated and compared with standard printing ink using petroleum based solvent. In general performance of the ester-based printing inks are comparable with that of the mineral oil based product. On the basis of tack stability and gloss, ester based inks are much superior than the mineral oil based products. In conclusion, a new non-volatile diluent for printing ink has been developed. The diluent is made from common vegetable oils like rapeseed, soybean, rice bran and palm oil, a renewable source that is environmental friendly. Vegetable oil esters offer a cost effective solution for mineral oil based printing ink to meet VOCs regulations.     

Evaluation of plant-based oils for production of offset printing ink

The oils and solvents are the main components of the printing ink, and the chemical composition of the ink could be harmful or toxic to human health and the environment. Therefore, there is an increasing demand to develop inks containing green, biobased, sustainable, and renewable raw materials instead of petrochemical substances. In this study, flaxseed oil (FO), pomegranate seed oil, plum kernel oil (PKO), and grape seed oil (GSO) were selected to produce offset printing inks. Pinus pinaster (P. pinaster) resin was also used in the formulation of inks to examine the effects of natural resin on ink together with vegetable oils. The phenolic content was analyzed for the resin and oils to figure out their potential antioxidant and bioactive characteristics. Optical and rheological tests were applied to evaluate the printability of the inks. L*a*b*, ΔE, density, and gloss tests were performed for optical evaluation. The viscosity, tack, and rub resistance tests were applied to perform rheological analysis. The biobased, environmental friendly, and self-drying (cold set) offset printing inks were obtained using natural pine resin and three different plant-based oils FO, PKO, and GSO. The printability analysis of the inks figured out the potential usage of plant-based oils in the offset printing ink formulation.     

Offset printing inks based on rapeseed and sunflower oil. Part I: Synthesis and characterization of rapeseed oil-and sunflower oil-modified alkyd resins

Two sets of alkyd resins of variable oil lengths with the required properties for offset printing ink formulations, modified by sunflower and rapeseed oil, were synthetized according to the “monoglyceride” process. The influence of the acyl composition of the modifying vegetable oil and of the oil content on alkyds’ properties was determined by detailed chemical and rheological characterization. Molecular structure, size, and molecule size distribution appeared to be linked to these two factors. A comparative study with two usual linseed oil-modified alkyds led to determination of the more appropriate alkyds for applications in offset varnishes.     

纯植物油型NON-VOC胶印油墨设计开发与探索

介绍了环保油墨的类型,分析了纯植物油油墨设计过程中遇到的问题,提出了相应的改进措施。纯植物油油墨是一种环保、性能优良、使用效果好并且节能的新型油墨。     

An ecological approach to printing industry: Development of ecofriendly offset printing inks using vegetable oils and pine resin as renewable raw materials and evaluation of printability

Petroleum-based solvents and synthetic resins are used as raw materials for the production of varnish, which is one of the main components of offset printing inks. These petrochemical compounds that are released to the surrounding in printing process demonstrates harmful effects on environment and human health. In the light of these facts, this study was carried out to investigate the use of renewable natural resources for offset printing inks production to lower environmental impacts and protect human health. In this study, different vegetable-based offset printing inks were developed with safflower oil (SO); grape seed oil (GSO) and Pinus pinaster resin (PPR) and printability analysis were performed. To understand the effect of pine resin in the ink formulation an ink sample with mineral oil (MO) was also produced. Printing tests were carried out with coated papers and the IGT C1 offset printability tester. Color, gloss, rub resistance, viscosity and tack values were measured on the test prints. Comparison of results with standard values figured out the suitability of using the newly developed offset printing inks for printing industry. The color difference values of color differences were in range of tolerance value. The density value of SO-PPR ink was found as same with standard values while the density value GSO-PPR and MO-PPR inks were measured close to standards as 1.45, 1.42, and 1.46, respectively. The results of printability analysis demonstrated appropriate utilization of the renewable sources for ecological development of offset printing inks.     

Ink-jet printing of cationised cotton using reactive inks

The ink-jet printing properties of cotton cationised with 2,3-epoxypropyltrimethylammonium chloride have been studied. Cyan, magenta, yellow and black reactive inks were used to print untreated and cationised cotton fabrics. The effect of cationic reagent concentration, steaming time, ink (colour) and print resolution were investigated, together with possible differences between the behaviour of the four inks. Colour yields, staining of the white grounds, penetration behaviour, print quality and fastness properties were evaluated.     

Methods for the evaluation of fine-line offset gravure printing inks for ceramics

The printing of ceramic substrates by offset gravure is well established industrially and is a potentially viable method for printing circuitry. Modified inks are required to be able to print fine lines at high resolution with minimal displacement and distortion. In the present study a statistical assessment of the role of the components of the ink binder has been undertaken, the inks being evaluated by printing tests and in terms of their rheology and cohesion. The results have been examined using a factor design program and the best-fit multivariate model established in order to describe the response to each factor. Based on the models, it was possible to increase the internal cohesion of the inks which gave a decrease in the rheological phase angle and an increase in print mass. It was found practicable to print lines as fine as 9 mm wide and dots as small as 20 mm diameter on ceramic substrates.     

Offset printing inks based on rapeseed oil and sunflower oil. Part II: Varnish and ink formulation

Two sets of variable oil length, alkyd resins modified by sunflower oil (SOA) and by rapeseed oil (ROA), were evaluated in offset formulations with mineral oils as diluent. The more suitable alkyds for this kind of application were determined. In a second experiment, hydrocarbon solvents were substituted by the fatty acid methyl esters derived from rapeseed oil or sunflower oil to produce ecologically friendly offset printing inks. Finally, the ROA and the SOA were associated with the methyl esters derived from the same vegetable oil. New properties of the varnishes composed of a vegetable diluent were evaluated. The quickset formulations with the methyl esters do not need important modifications, as opposed to the heatset formulations.     

Ionic liquids as performance additives for water‐based printing inks

For the first time, the use of ionic liquids as additives for printing inks in order to improve the wettability of the printing base by the ink is presented. The aim of this work was to study the influence of ionic liquids on the selected properties of water‐based printing ink and the prints. The contact angles of the printing inks on the printing base were measured. Modified flexographic inks were laboratory printed on polypropylene plastic film. The impact of small amounts of various ionic liquids on printing ink colour was examined in terms of the optical density of the full‐tone area, the colour parameters (L*, a*, b*, CIE), the total colour difference, and the gloss of the dried ink film. The influence of ionic liquids on the ink contact angle, the optical density, and the L*a*b* coordinates is discussed. In general, the investigated ionic liquids improve the wettability of water‐based flexographic printing ink, with an acceptable total colour difference. The optical density is increased for printing inks containing ionic liquids in comparison with the original flexographic printing ink, Process.     

Gamut evaluation of an n‐colour printing process with the minimum number of measurements

The aim of this study was to use a minimum number of measured colour patches to evaluate the colour gamut of an n‐colour printing process. Traditionally, the colour gamut of a printing system has been derived by printing and then measuring a gamut target for example, a profiling chart. For an n‐colour printing (printing with more than four process inks), it is desirable to know the colour gamut of the given set of inks without having to print a large number of test patches. Different spectral printer models were used to predict the gamut of a 7‐colour printing process. The colorant space was divided into sectors each containing four inks. For each printer model, the colour gamut of the each four‐ink sector was predicted. All sector‐gamuts were then combined to predict the overall colour gamut of the n‐colour process. This predicted gamut was then compared with the gamut obtained by measurement using a gamut comparison index (GCI). The Yule–Nielsen modified spectral Neugebauer (YNSN) model gave the best accuracy, at the cost of a larger number of input measurements, than other models. A combination of the Kubelka–Munk (KM) and YNSN models performed well with the fewest input measurements. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 408–415, 2015     

Single‐phase ink‐jet printing onto cotton fabric

The current commercial application of ink‐jet reactive inks to cotton fabrics requires pretreating with pad liquor containing a thickener, urea and alkali prior to printing. In this study, attempts have been made to develop a reactive ink‐jet print in a single‐phase process by adding an organic salt to the ink formulation and hence removing the need to pretreat fabrics. This approach utilises inks containing both a reactive dye, in this case Procion Red H‐E3B, and an organic salt such as sodium formate, sodium acetate, sodium propionate or tri‐sodium citrate. The behaviour of a novel reactive ink formulation for ink‐jet printing on to cotton fabric was evaluated at different pH vlaues. The results at optimum pH indicated that printed non‐pretreated fabrics with ink containing organic salts exhibited a higher level of reactive dye fixation than printed pretreated fabric containing no organic salt ink. The yielded prints demonstrate excellent colour fastness to washing and dry/wet crocking properties. The light fastness of the printed fabrics was improved by adding an organic salt to the ink formulation.     

Jet printing

Ink jet printers, some capable of producing a full colour gamut, are now widely used as output devices for computer-generated design work. Some advances have been made in the application of these ink jet paper printing technologies to textile printing, mainly for carpets. This review describes the principal jet systems that have been developed commercially for both textile and reprographic uses, and indicates areas in which the ink jet principle appears to have future potential. The physical and chemical requirements of the inks used in the different systems, as well as the possible pretreatment of the substrate to improve ink receptivity and the durability of the print, are also discussed.     

Effects on print quality of varying acrylic binder types in water-based flexographic ink formulations

The ink industry is one of the world's largest markets due to the increasing demand for printing inks for the packaging industry. Flexography printing is a well-known promising technology for large-area printing due to its high printing speed and roll-to-roll capability to print economically on a variety of surfaces and is used in nearly in all areas of packaging printing. Water-based inks are considered non-toxic, odourless, and more environmentally friendly options compared to solvent-based inks. Therefore, in this article, the goal was to develop new water-based ink formulation with different acrylic binders for flexographic printing on commercial solid bleached sulphate (SBS) board. Five inks were formulated with four different acrylic binders and compared to a commercially available ink to study their performance. The developed inks were investigated with regard to their print qualities and print characteristics. It was found that the binder type influenced some print quality while the effect was not significant for others. Using flexography printed cyan inks, the ink formulated with the highest molecular weight had the lowest print density and the largest tonal value increase (TVI) observed between 40 and 60 tone values. The same ink had the largest mottle values and variation in topography. For values of print contrast and delta gloss at 75°, although differences were observed between average values, data had inconclusive variation and spread around averages, where no conclusive trends or effects of acrylic binder type on these response factors were observed. Print chroma and dot roundness results were equally close for all printed samples.     

Printability of Sized Kenaf (Hibiscus cannabinus) Papers

This article reviews the effect of chitosan, cationic starch and polyvinyl alcohol as sizing agents to improve printability properties of kenaf handsheets. The polymers were incorporated into the sheets by spray application. This study clearly demonstrated that the use of chitosan could improve the printability and print quality of kenaf paper in terms of water and oil absorption, ink penetration, print density and gloss for offset printing. Both PVA-sizing and cationic starch sizing gave print densities and ink penetrations than were intermediate between chitosan and the unsized control sheet, which gave the lowest values for these properties. Kenaf paper sized with chitosan gave the best mix of desirable printing paper properties and was superior to kenaf papers sized with either cationic starch or PVA.     

Pretreatment effects on pigment‐based textile inkjet printing – colour gamut and crockfastness properties

The application of two commercial pretreatment agents, formulated to improve the performance of a six‐colour nano‐scale pigment ink set during the textile inkjet printing of cotton and polyester (PET) fabrics, was examined. An industrial scale printer, operating at 55 linear m/h and equipped with Kyocera printheads, was used to print on commercial fabrics (180 cm wide) prepared for digital printing. The work employed an industrial scale rather than a benchtop printer to enhance the utility of the results for a commercial environment. The colorimetric attributes of printed fabrics were recorded for the individual inks as well as for spot colour combinations generated using Dr. Wirth RIPMaster v11 software. Colour table profiles were also generated and the colorimetric values of inks were compared. Colour gamuts of inks on cotton and PET, including three‐dimensional volumes in the CIELab space, were examined to assess the role of pretreatment on the colorimetric properties of the printed substrates. It was found that the pretreatments enhanced the ink receptiveness, colour intensity and colour gamut of fabrics. Pretreatment of cotton resulted in a larger gamut and more vivid colours than on PET. However, wet and dry crockfastness results were found to be low. In this regard, Time‐of‐Flight Secondary Ion Mass Spectrometry analysis of fabrics printed in the presence and absence of pretreatment indicated that the low crockfastness arises from higher pigment levels on the surface of the pretreated fabric.     

全色彩环保油墨

通过分析油墨的基本组成可知：溶剂对环境的影响最大。与矿物油、植物油相比，源于木材加工业的松浆脂肪酸酯在油墨中作溶剂，其化学结构、黏度及挥发性能具有很多优点。而且，所制成的植物油型油墨在胶印性能、生物降解、气味、提高印刷效率方面效果极佳。目前，在环保要求与资源可再生性利用的压力下，植物油型油墨必将越来越受青睐。     

Ink‐jet printing of cotton with natural dyes

Four natural dyes, annatto, cutch, pomegranate fruit rind, and golden dock, were used as colorants for the preparation of water‐based ink‐jet inks for digital textile printing. The physical and rheological properties (pH, conductivity, surface tension, and viscosity) of the inks were measured over a period of 90 days for the evaluation of ink stability and suitability for ink‐jet printing. The inks were found to be suitable and were used for the digital printing of cotton fabrics. The prints were subjected to wash, light, and rub fastness tests and colour measurements. Colour consistency and fastness results, especially after fixation, are comparable with those of synthetic dyes, which paves the way for the production of environmentally friendly ink‐jet inks using natural dyes for the digital printing of cotton through the formulation of suitable printing techniques.     

Gravure offset printing of polymer inks for conductors

A gravure offset printing process has been developed for Ag-filled polymer conductor ink. Pad printing and roller type printing have been used. Curing and electrical properties have been studied. A roller type of gravure offset printing has been used to evaluate the printing process and pad printing to print on the non-planar substrates. Based on differential scanning calorimetry (DSC) and resistivity measurements during ink curing, it was found that the ink had an optimum curing temperature of 140 °C. Square resistance of 300 and 150 μm wide lines can be as low as 20 and 28 mΩ/sq., respectively, for 7–8.5 μm thick line. The minimum line width was 70 μm. This minimum line width can be reduced with different ink solvents, but in this case the line thickness suffers and the square resistance increases, respectively.     

Improvement of light fastness of water‐based printing inks with addition of glycerol derivative containing thiol groups

The aim of this work was to study the influence of a glycerol derivative with thiol groups, 3,6‐dithia‐1,8‐octanediol (DTO), on light fastness of prints overprinted with water‐based flexographic printing inks. Laboratory printing was performed on various plastic films (BOPP and PE). The effect of a small amount of DTO on printing ink colour was examined by studying the optical density of a full tone area, relative printing contrast and the colour values (CIELAB), and the total colour difference, . Artificial ageing was applied in order to investigate DTO influence on colourfastness of CMY printing inks. Densitometry and spectrophotometric parameters were measured during artificial ageing by irradiation. Additionally, FTIR spectroscopy was used to observe the changes in ink film on printing bases before and after ageing. The print quality of investigated prints is widely discussed. In general, DTO addition influenced the printability of the plastic film and the optical density of a full tone area with an acceptable total colour difference . Furthermore, printing inks with added DTO exhibited higher optical density and smaller changes of during artificial ageing. Moreover, the FTIR spectra of printing ink films with added DTO after ageing did not exhibit any perceptible changes in contrast with the original printing ink.     

凝胶型连结料体系黏度模型的参数拟合

采用有机铝型螯合物凝胶剂、松香改性酚醛树脂、亚麻仁油和高沸点煤油制备胶印油墨用连结料,研究了亚麻仁油、高沸点煤油和凝胶剂的用量对连结料流变性能的影响。根据流变实验测定值,准确地拟合出该连结料体系的一系列黏度模型。根据该黏度模型,能够在改变原料配比、温度与剪切速率的条件下,相当精确地描述连结料体系的黏度。因此,若能利用汇编语言设计出连结料的配方计算软件,则可根据连结料体系中各因素变化来直接调节连结料的流变参数,达到快速调整连结料配方、缩短生产工艺时间、稳定连结料质量、适应高速印刷油墨要求的目的。