Offset Printing Research Articles

Studying on Producing the Fluoresence Offset Printing Ink

The fluorescent offset printing inks are the popular materials used in security printing. The producing process of offset ink includes two main steps as mixing components and grinding ink. This paper presents the studied results regarding the determination of the optimized conditions of the fluorescent offset ink producing process. Three design factors are evaluated as the varnish content, pigment content, and an enhanced degree of roller pressure. The target of the regression function is the particle size of the fluorescent offset ink. The box-wilson steep ascent method and the first-order mathematical model were applied to design a factorial experiment. The optimal conditions obtained from the surface response are varnish content of 74 % by weight, pigment content of 16 % by weight, and pressure enhance of 20 bar. Additionally, the fluorescent offset ink samples prepared under the optimized conditions meet the standards of offset ink namely viscosity, tack value, particle size, and fluorescent properties.

Forecasting the Number of Offset Printing Machine Breakdowns Using the Support Vector Machine (SVM) Metdhod

PT. MJT is a company engaged in manufacturing that produces various types of plastic tubes for cosmetic packaging. Production activities at PT. MJT uses an intermittent process, which in the printing division requires a longer total setup time because this process produces various types of specifications of goods to order. This has an effect on the amount of engine breakdown. The purpose of this research is to try the method of forecasting the number of breakdowns for offset printing machines at PT. MJT. One of the methods used in this research is the Support Vector Machine method. Support Vector Machine is a method that can help predict the number of breakdowns that will be experienced by the offset printing machine at PT. MJT. Support vector machine is a method that can reduce the error value in forecasting compared to other methods. From this research, it is hoped that it can produce a forecast of the number of breakdowns for offset printing machines at PT. MJT for a period of one year or twelve periods.

Analisa Interaksi Pegawai Pada CV. Diamond Printing Menggunakan Social Network Analysis (SNA)

Diamond Printing is one of the largest offset printing companies with 32 years of experience and is located in the city of Surabaya, East Java. Data from HRD managers explained that there was no report from observations related to employee work effectiveness in terms of coordination and synergy between employees as seen from the communication and collaboration relationships. The absence of data related to the effectiveness of the performance of CV employees. Diamond Printing in terms of communication network mapping is one of the obstacles faced by HRD in determining KPI (key performance indicator). By using the Social Network Analysis (SNA) method with the help of UCINET 6 software, it is hoped that some employees will have advantages, especially in collaboration and communication in group network structures. There are three parameters used in SNA, including: degree centrality, closeness centrality, and betweenness centrality. This study involved 104 respondents (the entire population) with a sampling technique using snowball sampling and a questionnaire as a means of collecting data. The results of this study indicate that most of the collaboration and communication network interactions are dominated by manager level employees and department heads. Based on these findings, an innovation is needed from all stakeholders from CV. Diamond Printing in developing effective communication methods between its members.

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

AbstractPetroleum‐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.

Tunable Reverse Offset Printing with a Stretchable Blanket for Fabricating Flexible Printed Electronics

The cover page shows the illustration of controlled pattern shrinkage in reverse offset printing. Young Tae Cho and co-workers demonstrate in their article, number 2001537, that the pattern size reduction by a flexible blanket material with simple mechanical stretching and releasing shed light on the low-cost, scalable, and high-resolution printing for printed electronics.

Colorants in printing applications

Abstract This review article is a summary of the current knowledge in the field of colorants in printing applications. Printing inks belong as well as paints, coatings, plastics, and cosmetic formulations to the most important application systems for colorants, both for pigments and dyes. Colorants have to meet increasing demands in printing applications due to the considerable number of printing methods and consequently of a large number of specific printing formulations. Crucial factors besides the specific properties of a certain printing ink are the processing method and the required quality of the final printed product. Amongst the most important printing methods are letterpress printing, offset printing, flexographic printing, gravure printing, screen printing, and digital printing. Different processing methods are used for coloring of the individual printing inks. The coloring processes need to be coordinated in accordance with the steps of the printing processes leading to the final product.

1,2-Dichloropropane induces γ-H2AX expression in human cholangiocytes only in the presence of macrophages

Recent epidemiological studies reported cases of cholangiocarcinoma in workers exposed to 1,2-dichloropropane (1,2-DCP) in an offset proof printing factory in Japan. The present study investigated the effects of 1,2-DCP on the expression of histone family member X (H2AX) phosphorylated on Ser 139 (γ-H2AX), a marker of DNA double strand break, in human immortalized cholangiocytes MMNK-1 cells. Mono-cultures of MMNK-1 cells and co-cultures of MMNK-1 cells with THP-1 macrophages were exposed to 1,2-DCP at concentrations of 100 and 500 μM for 24 h. Expression of γ-H2AX was visualized by immunofluorescence staining. Exposure to 1,2-DCP had no effect on the expression of γ-H2AX in mono-cultured MMNK-1 cells, but significantly increased the number of nuclear foci stained by γ-H2AX in MMNK-1 cells co-cultured with THP-1 macrophages. Exposure to 1,2-DCP also significantly increased the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in co-cultured MMNK-1 cells. The results suggest that macrophages play a critical role by producing cytokines in 1,2-DCP-induced DNA double strand break in MMNK-1 cells.

Back-trap mottle: A review of mechanisms and possible solutions

Print mottle is a serious and common uneven printing defect that occurs when printing coated paper by the offset multicolor printing process. It is characterized by a non-uniform appearance in terms of brightness, gloss, or color density that appears mostly in solid printed areas. Back-trap print mottle and water-interference print mottle occur when the quality of the paper substrate, especially the coating layer quality, is not satisfactory. To cope with this quality problem of coated papers, the understanding of the offset printing process, the requirements of coated-paper quality, and the reasons for this problem should be addressed. In this review, the basic process of offset printing and the mechanisms of print mottles were explored, the importance of coating uniformity in both the coating structure and process was reviewed, and the approaches to cope with print mottle were introduced.

Offset printing results analysis of different based inks in cardboard packaging production

Abstract The main raw material of paper and cardboard used in packaging is cellulose. Cardboard packages made of cardboard, which can be produced in much different quality and weight, are obtained in numerous shapes and appearances 1, 2 . Paper and cardboard packaging are among the most economical packaging types. Using less raw materials, more durable but thin, light, economical cardboard is produced 2, 3 . In this study, under equal printing conditions, test prints were made on cardboard substrates (for cardboard packaging) with mineral oil based, vegetable oil (soy oil) based and UV cured inks used for the printing of the same images. After these prints, the properties of mineral oil, vegetable oil and UV ink; the effect on the print results was measured from different ways (Chroma*, Print density, unprinted surface Gloss 75°, Print Gloss 60°). At the same time, the visual differences between the print results were determined by the optical imaging (SEM) method and were examined by the elemental analysis method.

Self-excited Vibration of Ink Rollers

A vibration having a character of self-excited chatter oscillation known from machine tools is observed during intermittent motion of ink rollers of offset printing machines. This vibration occurs under specific operating conditions and is often accompanied by an increased noise level. To explain this unusual vibration behavior, a simple analytical model of two rollers interaction is derived. The calculated oscillation is compared with the measurement of ductor roller displacement. The model results confirm the possibility of self-excited vibration development in the presence of viscous forces, negative damping effects and continuous supply of external energy from roller rotation.

A Study on the Selection of Highly Flexible Blanket for Reverse Offset Printing

A Study on the Selection of Highly Flexible Blanket for Reverse Offset Printing

Facile and Low Cost Temperature Compensated Humidity Sensor and Signal Conditioning System

Most relative humidity sensors are resistive or capacitive sensors. It’s a fact that the resistance and capacitance of a vast majority of such sensors also depend on the surrounding temperature and a change of temperature can cause significant errors in the final reading of relative humidity. This fact of temperature dependence is scarcely investigated in development of humidity sensors. In this work, a very simple temperature compensation method has been developed that automatically eliminates the effect of change in temperature from the final output without requiring separate measurement of temperature or any data processing. Amorphous polyethylene oxide (PEO) was used as the active material for humidity sensor owing to its high sensitivity and almost linear response. Interdigitated type sensor electrodes (IDE) were fabricated using reverse offset printing on glass substrate and the active layer was deposited through spin coating. An identical twin sensor was fabricated with the same parameters and was additionally encapsulated form the open environment. The dummy sensor was used as opposing pair with the active sensor in a bridge configuration to achieve temperature compensation. The bridge sensitivity was recorded to be ~2.9 mV/%RH that was further improved to 100 mV/%RH using a differential instrumentation amplifier based signal conditioning circuit. The sensor system was deployed in a real-life relative humidity measurement with changing temperature that returned a remarkable accuracy of 98.76%. The error due to temperature dependence reduced from 22.4% to just 1.24%. The transient response time of the sensor was found to be ~2.4 s.

Fabrication of rosemary essential oil microcapsules and using in active packaging

Abstract Essential oils are interesting plant extracts that are used for preservation in food field. They can be used in antibacterial food packaging systems. The disadvantage of essential oils is that they degrade due to light and heat and lose their biological activity. Encapsulation techniques enable essential oils to be protected them. In this study wall material maltodextrin and whey protein concentrate were used. The emulsions were prepared with rosemary oil and wall material. Freeze dried capsules were synthesized. The encapsulation efficiencies, surface morphologies and particle size distributions were determined. In addition, the paper coating formulations were prepared with rosemary oil capsule by different concentrations and applicate them onto the paper. Antimicrobial test was applied to both gram negative and positive bacteria on the coated papers. In addition, color, gloss and contact angle were measured by spectrophotometer, glossmeter and goniometer, respectively. The offset test prints were made on the coated papers, and the color and gloss of the prints were measured and the color changes were calculated. As a result, capsules with rosemary oil were produced. It was determined that rosemary coated papers showed activity against E. coli bacteria and this paper could be used in active food packaging.

Dynamic Compression Model Incorporating Elastic Nonlinearity of Paperboard

Spring of constant elasticity is a concept from theories of extension while elastic nonlinearity in compressive deformation is a general phenomenon for polymeric materials involved in offset or flexographic printing, paper board, polymer plate, and cushioning tape. This phenomenon needs therefore to be coped with by the model of printing dynamics. We hereby present an extended approach based on the Maxwell material model. In the extended approach, a compression process is subdivided into (or approximated by) sequential subprocesses. The elastic modulus may vary from one subsection to another but remains constant in each of the subprocesses. With the extended approach dynamic behaviours (compression/recovering) of paperboard can be reproduced and predicted. As a concrete example, dynamic behaviours of paper board in the print nip were simulated with satisfactory outcome. The simulation also revealed that viscoelasticity of the board is the origin of mechanical hysteresis of the stress–strain curve. Due to viscoelasticity and nonlinearity of the materials careful design is essential to simulate full-scale printing with a lab press.

Prediksi Persediaan Bahan Baku untuk Produksi Percetakan Menggunakan Metode Asosiasi

The use of technology in the offset printing industry is now making it faster for users to get production results. Another advantage of the offset printing industry is high quality printing, consistent color printing and low cost for large volume printing. The offset printing industry is one of the industries that have the most frequent ordering of raw materials, this is due to the pattern of consumers who order more than one type of paper. Therefore, the unavailability of raw materials can cause the order to be constrained. By using this association method, it can be seen the amount of paper raw material needed to complete a product in the future so that the company can optimize the supply of raw materials needed so that the amount of inventory is not too much but not too little. In this study the support used has a threshold of more than 20% and a minimum confidence 30%. With these results can be optimized in the subsequent ordering of raw materials for paper and can manage the storage properly.

A Study on the Assessment of Quality of Printed Sheets in Offset Sheet-Fed Printing

The quality parameters of printed sheets should be controlled constantly during the sheet-fed offset printing process. This allows the detection of any problems in the initial stages of the printing process. The final control of the quality of printing sheets will eliminate error products before delivering to the costumers. The results of this control should be analyzed continuously. The total quality management (TQM) is an effective method in controlling, doing statistics, and assessing the errors in the offset printing process. Simultaneously, this method delivers the main errors frequently occurred in the printing process. This paper presents the possibility of using some tools of the TQM method such as Pareto chart, Ishikawa diagram, and 5xWhy to analyze and assess the quality of printing sheets in sheet-fed offset printing. The studied results show that the two main errors of the printed sheets are hickeys (occupied 29 %) and low density (occupied 17%). Moreover, the causes of hickey error are analyzed and shown in this paper.

Studying on Water pick-up Characteristics of UV Curable Offset Ink and the Fountain Solution without IPA

In UV curable offset printing, ink-water balance is difficult to control, especially in using fountain solution with IPA. The studying on fountain solution without IPA is an essential problem to meet the requirements of the friendly working environment and the UV curable offset technology. In this paper, water pick-up characteristics of the different color UV curable offset inks were determined using the Duke Emulsification Tester. The influence of BCS concentration and process color UV curable offset inks on the water pick-up characteristics were tested using Analysis of variance (ANOVA). Moreover, the obtained fountain solution is compared with the commercial fountain solution in the emulsification capacity. Results show that the fountain solution of BCS 15 % concentration forms the stable emulsification system with all process color UV curable offset inks. The differences of BCS concentrations and color UV curable offset inks have different water pick-up characteristics (p < 0,05). The water pick-up characteristics of three color inks as C, M, and Y with the obtained fountain solution of BCS 15 % concentration are around 25 %, meanwhile, the water pick-up characteristic of Black (K) ink is approximately 20 % after half measuring time. Finally, the obtained solution of BCS 15 % concentration is equivalent to the commercial fountain solution (COMBIFIX-XL) in the emulsification capacity of the inks.

Relationship between risk perception toward hearing conservation and using hearing protection devices among offset printing workers in Tehran province, Iran

The way workers perceive noise exposure can play an important role in the adoption of safety behaviors. Therefore, the determination of the relationship among risk awareness, behavior, and exposure can be an extremely important issue in controlling noise exposure. The aim of this study was to investigate the association between risk perception and practice of workers. Workers from 16 printing houses in Tehran province participated in present study. A questionnaire was used for determining the level of risk perception and practice about hearing conservation. The results revealed a significant relationship between risk perception and safety behavior adoption (P < 0.001). A positive and significant correlation was found between these two variables (P < 0.001; rs = 0.912). Also, the results showed that workers with hearing impairment had a better practice. In addition, attention should be paid to preventive principles and encouragement of hearing protection devices usage among employees.

STUDY OF WETTING ON THE NON-IMAGE AREA OF OFFSET PRINTING PLATES BY AN ALTERNATIVE ISO-PROPYL ALCOHOL-FREE FOUNTAIN SOLUTION

In this study, an alternative aqueous isopropyl alcohol-free fountain solution for sheet-fed offset printing is prepared comprising 5 w/w% McIlvaine's buffer system for pH control, 0.3 w/w% Polysorbate 80 as a surfactant, 1 w/w% magnesium nitrate hexahydrate as a conductivity agent and 10 w/w% ethylene glycol mono-butyl ether as an additional wetting agent. The percentages of each composition are w/w% of active and then adjusted to 100 w/w% by adding distilled water. The contact angles of the obtained fountain solution on non-image areas of three common offset printing plates: CTP plate of Kodak, CTP plate of Huaguang Graphic Co. Ltd (China), and CTP plate of Mylan Printing Media Co. Ltd (Vietnam), range from 10° to 20°.The surface tension, conductivity, pH and viscosity were found to be 30.5 mN/m, 1.45 mS/cm, 4.8, and 1.05 x 10-2 g/cm.s, respectively. In comparison to the commercial fountain solution (KF – Trade Mark (China) containing isopropyl alcohol (IPA), the obtained fountain solution shows similar wettability on the non-image area of the offset printing plate whilst having similar physico-chemical parameters. The results indicate that ethylene glycol mono-butyl ether could be a potential substitute for IPA in fountain solution in offset printing, and the obtained fountain solution displays suitable properties for the offset printing process.

AHP and TOPSIS Integration for Green Supplier Selection: A Case Study in Indonesia

Recently, the problem of global warming arising from manufacturing activities has attracted attention. One of the triggers of global warming is the aspect of production. This aspect requires raw materials supplied by the supplier. The selection of the right supplier by considering environmental aspects can reduce the problem of global warming. The purpose of this study is to integrate the AHP and TOPSIS methods in green supplier selection. Eight criteria are used to select suppliers weighted by the AHP method. AHP weighting results are used to select suppliers with the TOPSIS method. A case study was applied to an offset printing company in Indonesia. The results show that the quality criteria have the highest importance. In addition, the results showed that the AHP and TOPSIS methods were easy to use in Green Supplier Selection.