Combining simulation and on-line measurements to determine moisture transport dynamics throughout the heatset offset printing process

Purpose The purpose of this paper is to investigate the influences of fibre lengths and a given range of paper grammages on the fundamental properties of unprinted and printed papers by using mineral oil-based offset printing inks and also evaluate these results in terms of printing and tensile characteristics. Design/methodology/approach A design research approach has been based on the production of various laboratory handmade papers and their printing process with mineral oil-based offset printing inks. The analysis of mechanical and structural tests results of the unprinted and the printed papers have been evaluated. Findings This study is confirmed that the mineral oil-based offset printing inks can be easily applied to the surface of papers having different grammages and pulp contents. An increase was observed in the tensile index values of the papers with the printing process, and these increases were more evident (about 80%) particularly in low grammage papers having high short fibre content. Originality/value The originality of this work is based on understanding and comparing the effects of grammage and the effect of pulp contents (having long and short fibre) on tensile characteristics of printed and unprinted handsheets.

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Optimization of a reverse-offset printing process and its application to a metal mesh touch screen sensor

Microelectronic Engineering ◽

10.1016/j.mee.2014.12.007 ◽

2015 ◽

Vol 134 ◽

pp. 1-6 ◽

Cited By ~ 35

Author(s):

Young-Man Choi ◽

Eon-Seok Lee ◽

Taik-Min Lee ◽

Kwang-Young Kim

Keyword(s):

Touch Screen ◽

Offset Printing ◽

Metal Mesh ◽

Printing Process

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Environmental impact of printing inks and printing process

Journal of Graphic Engineering and Design ◽

10.24867/jged-2020-2-011 ◽

2020 ◽

Vol 11 (2) ◽

pp. 11-17

Author(s):

Cem Aydemir ◽

◽

Samed Ayhan Özsoy ◽

Keyword(s):

Organic Compounds ◽

Ground Level ◽

Printing Industry ◽

Offset Printing ◽

High Concentration ◽

Negative Effects ◽

Glycol Ethers ◽

Printing Process ◽

Printing Inks ◽

The One

In the Printing Industry, printing inks, varnishes, lacquers, moistening solutions and washing solvents (ethanol, methyl acetate, ethyl acetate, isopropanol, n-propanol, hexane, benzene, toluene, xylene, isopropyl acetate, propyl acetate, dimethyl ketone, glycols and glycol ethers) contain volatile organic compounds (VOCs) and air pollutants (HAPs). Especially solvent based inks used for flexo, gravure and screen printing, offset printing dampening solutions and cleaning solvents contain high concentration of VOC. These organic compounds evaporate during the production process or contribute to the photochemical reaction. VOCs and HAPs, together with sunlight and nitrogen oxides, cause photochemical smoke, air particles and ground level ozone emission in the atmosphere. The VOCs and heavy metals can lead to soil and even water pollution when left in landfill. The amount of solvent retained by flexo, gravure and screen-printed products is 3-4% of total ink solvent used. The solvent in the printed ink content, except for the one held by the printed material evaporates in its own environment after the printing process. Most of these solvents and organic compounds used in printing environment contain at least one carbon and hydrogen atom and have negative effects on health and environment.In this study, the environmental impacts and risks of inks and solvents used in the printing industry have been evaluated. Measures to be taken to reduce and manage these environmental effects and risks have been addressed and recommendations have been made.

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THE PHENOMENON OF INK DUSTING TAKING INTO ACCOUNT THE SURFACE ROUGHNESS OFFSET PRINTING PLATE

Labour protection problems in Ukraine ◽

10.36804/nndipbop.37-2.2021.16-24 ◽

2021 ◽

Vol 37 (2) ◽

pp. 16-24

Author(s):

I. Khalilov ◽

E. Aliyev ◽

E. Huseynzade

Keyword(s):

Surface Roughness ◽

Contact Zone ◽

Friction Pair ◽

Gear Ratio ◽

Total Force ◽

Offset Printing ◽

Printing Plate ◽

Friction Forces ◽

Printing Process ◽

Roughness Model

The paper investigates the influence of the mechanics of a friction printing pair on ink dusting in the printing process, taking into account the surface roughness of the printing plate. The aim of the study is to determine the influence of the surface roughness of the printing plate on the deformation of the deckle, as well as on the value of the total force in the area of the printed contact, the relative gear ratio and the relative speed of sliding of the deckle along the surface of the cylinder, which directly affects the dusting of the ink. It was found that when studying the mechanics of a printed pair, the influence of the microgeometry of the contacting surfaces on the parameters under study was not taken into account. The influence of microprotrusions of the surface roughness of the printing plate on the deformation of the deckle in the area of the printed contact has been substantiated and established. To determine the introduction of surface roughness irregularities, a discrete roughness model is used, presented as a set of identical spherical segments. To determine the influence of the surface roughness of the printing plate on the friction force arising in the contact zone, a calculation scheme is proposed that differs from analogs. A method is developed for calculating the parameters of a friction pair in the printing process, taking into account the roughness. Expressions are obtained for determining the total moment of tangential friction forces in the sliding sections when spherical irregularities are introduced. According to the proposed technique, the corresponding graphical dependences of the gear ratio on different parameters of the friction printed pair are shown. The advantages of this study in comparison with analogs are that at certain values of the parameters of the friction pair, taking into account the surface roughness of the printing plate, also at known values of the mechanical characteristics and thickness of the deckle, it is possible to determine the change in the length of the deckle of a given composition, which is necessary in the printing process. The proposed calculation method, which is carried out without taking into account the pressure in the printed contact zone, allows predicting the quality of printed impressions and the amount of ink involved in the formation of ink dusting, as well as correctly adjusting the printing press before the printing process.

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

JST: Engineering and Technology for Sustainable Development ◽

10.51316/jst.148.etsd.2021.31.1.9 ◽

2021 ◽

Vol 31 (1) ◽

pp. 41-45

Keyword(s):

Quality Management ◽

Total Quality Management ◽

Quality Parameters ◽

Low Density ◽

Total Quality ◽

Offset Printing ◽

Pareto Chart ◽

Printing Process ◽

Ishikawa Diagram

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.

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Moisture in Textiles

Annual Review of Fluid Mechanics ◽

10.1146/annurev-fluid-030121-034728 ◽

2021 ◽

Vol 54 (1) ◽

Author(s):

C. Duprat

Keyword(s):

Moisture Transport ◽

Soft Matter ◽

Model Systems ◽

Annual Review ◽

Publication Date ◽

Knitted Fabrics ◽

Common Features ◽

Transport Dynamics ◽

The Common ◽

Fibrous Assemblies

The interactions of textiles with moisture have been thoroughly studied in textile research, while fluid mechanists and soft matter physicists have partially investigated the underlying physics phenomena. A description of liquid morphologies in fibrous assemblies allows one to characterize the associated capillary forces and their impact on textiles, and to organize their complex moisture transport dynamics. This review gathers some of the common features and fundamental mechanisms at play in textile–liquid interactions, with selected examples ranging from knitted fabrics to nonwoven paper sheets, associated with experiments on model systems. Expected final online publication date for the Annual Review of Fluid Mechanics, Volume 54 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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Optimization of Technical Parameters on the Color Variation in offset Printing Process

International Journal of Scientific Research in Science Engineering and Technology ◽

10.32628/ijsrset196655 ◽

2019 ◽

pp. 229-234

Author(s):

Tu Thanh Nam ◽

Hoang Thi Kieu Nguyen

Keyword(s):

Factorial Design ◽

Color Difference ◽

Color Variation ◽

Optimal Conditions ◽

Offset Printing ◽

Printing Process ◽

Optimization Of Parameters ◽

Technical Parameters ◽

Desirable Response ◽

Ink Transfer

In this study, the optimization of parameters of the printing process was carried out. The aim is to minimize the size of color variation in prints. A factorial design was used to evaluate the effects and interactions of three factors, that is, impression pressure, alcohol %, and press speed. The color variation is gauged by variation in ink transfer, which is governed by color difference (?E). The optimal conditions obtained from the desirable response are impression pressure of 0.15 mm, alcohol percentage of 12.2 % and press speed of 8500 sheets per hour. Under these conditions, about 0.62 of color difference is obtained.

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Preventive maintenance features specific to offset printing machines

MATEC Web of Conferences ◽

10.1051/matecconf/202134308012 ◽

2021 ◽

Vol 343 ◽

pp. 08012

Author(s):

Emilia Bălan ◽

Liviu Berculescu ◽

Răzvan-George Răcheru ◽

Dorin Vasile Piţigoi ◽

Lucia Adăscăliţa

Keyword(s):

Preventive Maintenance ◽

Offset Printing ◽

Printing Process ◽

Machine Performance ◽

Continuous Quality ◽

Study Results ◽

Maintenance Activities ◽

Printing Processes

In the printing industry, where production never stops, it is very important to continuously maintain machine performance. If a machine breaks down, the production will stop and it will disturb the production process. Therefore, the maintenance system must be managed efficiently to solve those problems. The paper presents the study results on continuous quality improvement of offset printing using preventive maintenance features. Offset printing is a process that involves a multitude of variables, independent and interdependent factors. The offset printing process was analyzed and the factors that have a significant influence on the quality of the process and the products made were identified. The defects that may occur during the printing process and the causes thereof have also been identified and the types of non-conformities of the end products were estabilished. The experimental method was used. The case study was conducted on Manroland 508. For the planning of preventive maintenance activities, the duration of the maintenance works necessary to ensure the proper functioning of the offset printing machines was established. Finally, maintenance activities that would guarantee and continuously improve the quality of the printing processes and the printed products were issued.

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