• 한국인쇄학회지
• /
• 제29권1호
• /
• pp.75-83
• /
• 2011

As screen printing is changed by automation recently, could print more exactly. However, must suffer great many trial and error to have still gotten perfect result. By the way, at this step, fair time and money should be invested. Therefore, if search for optimum condition in early time visualizing screen printing process using simulator program before progress printing, is judged that may be correct and gets printing result efficiently. In this paper, searched optimum printing speed and ink viscosity using FLOW-3D program. Also, the result could confirm truth that is agreeing almost with experiment contents. Through this, is thought that may expect extension of screen printing wide application that vivify advantage of screen print if use simulation program.

• 한국인쇄학회지
• /
• 제19권1호
• /
• pp.42-54
• /
• 2001

The combination of a silicone surfaced plate and high viscosity ink produced a waterless printing system that worked well, but had limitation. The limitation was that this system was restricted to relatively short run lengths. In the waterless printing process, the press tended to heat up rapidly. Heat in turn, broke down the resins in the inks, causing them to become more fluid. When the ink is heated, the viscosity will drop, the ink will become too liquid and the plate will no longer be able to resist it. The ink will adhere to the non-print portions of the plate, and will print as a very fine mist or speckle pattern in the non-image area. On the other hand, when the ink gets too cold, viscosity will increase until ink transfer is impeded. This study carried otu to investigate the effect of temperature variations of the inks on the print quality in waterless lithography and to examine the adaptability of waterless lithography to conventional offset press without cooling system.

• 한국인쇄학회지
• /
• 제10권1호
• /
• pp.55-67
• /
• 1992

The character of standing box printing reguires a rich representation on a light and a shade of color and cause the modern photographs to be abundant of the ink and also show the continuity of which any other printing is incapable because of its profound gradation.The clear printing in gravure can be said to be due to the good transfer of the ink-the completion of the transference of the ink into the stencil paper and the clear transference of the printing tone.The most inportant matter is the distance between the printing press and the doctor line. It is the matter of the structure and arrangement because of giving the most affect on the dryness of the ink in the cell.The glue of the ink in gravure changes by the kinds of the dye and the cellusolve used.

• 한국정밀공학회지
• /
• 제30권6호
• /
• pp.573-577
• /
• 2013

The one of the most important issue in roll-to-roll gravure printing is increase of ink transfer ratio or printability. As the result of high ink transfer ratio or printability, we can assess the quality of the printed patterns. The rheological properties are the important factors for the printability of electrodes patterning. In this study, the rheological properties of conductive ink are controlled by adding the solvent. The inks with different rheological properties are used for the patterning of the electrodes of $100{\mu}m$ by gravure printing equipment. The various printing speed, which also affect the rheological properties of conductive ink, is applied and the printed patterns are compared for their width and aspect ratio. Decreasing in the ink viscosity as well as increasing in the printing speed decreases the printability in gravure patterning, which shows that the rheological properties are important factors for the printability of gravure patterning.

• 월간포장계
• /
• 통권105호
• /
• pp.178-185
• /
• 2002

• 한국인쇄학회지
• /
• 제21권2호
• /
• pp.21-29
• /
• 2003

In gravure printing, all of the ink in the gravure cells does not leave the cell onto the substrate. The ink transfer from plate to paper in the gravure printing was simulated by computer. A few studies have dealt with cell withdrawal with simplified Newtonian flow models however, this work was performed with the non-Newtonian inks with different simulation software.

• 한국인쇄학회지
• /
• 제20권2호
• /
• pp.69-83
• /
• 2002

This research attempts on plate making for gravure. Direct Hard Dot Method, Helio Kliso Graph, and Laser TB Dot; these three method are the most popular in Korea. For examining ink transmission, three plates were made in the above three different way for the same manuscript and were printed under the same condition. After printing speed was also varied into 150line/inch, 175line/inch, and 200line/inch, ink transmission was examined too. After printing the same manuscript with the above three method then the researcher examined level of ink transmission. Printing lines shows that Laser TB Dot Method and Direct Hard Dot Method were favorable level, while there was big differences of state of Helio Kliso Graph plate.

• 펄프종이기술
• /
• 제44권4호
• /
• pp.77-84
• /
• 2012

The lithographic process depends on a satisfactory ink-in-water emulsion being formed during printing and the speed of wet presses makes the choice of fountain solution vitally important as the ink and fount must react quickly to form a stable emulsion. Ink and water come into contact with each other on the rolls of the press and are forced together in the roll nips. The water is not soluble in the ink since it is slightly fat. Instead, an emulsion is formed, a heterogeneous mass consisting of small water drops mixed into the ink, if the water feed is too great. This emulsification can affect the properties of an off-set ink and negatively affect the printability. So we investigated the effects of the emulsification of phenol free heat-set ink and existing heat-set ink on printed quality, such as amount of ink transfer, printed density, print-through and uniformity. We used Duke emulsification tester for the emulsification of inks, and used IGT printability tester for printed quality. The printed quality were measured by densitometer and were evaluated by the image analysis system. Compared to conventional printing ink, phenol-free ink showed better results of the printability at the emulsification.

• 펄프종이기술
• /
• 제38권4호
• /
• pp.41-46
• /
• 2006

Printed mottle of coated paper is one of the most common but the most difficult problem in offset printing. Printed mottle is caused by an uneven penetration of Ink into the paper, binder migration, etc. For a high quality printing, development of new paper coating technologies to prevent print mottle is required. So for, the study of solving printed mottle is coated paper absorption controlled by base paper sizing and coating layer binder migration control. As a results, printed mottle has improved in coated paper. But printing is worked by interaction of printing ink, coated paper and printing pressure, then we need to understand of interaction printing work and coated paper. This research focused on a way of improving printed mottle by investigating various printing conditions such as ink dispersion, nip condition and amount of ink transfer using IGT printability tester.

• 한국인쇄학회지
• /
• 제24권1호
• /
• pp.1-12
• /
• 2006

The rheological characteristics of an ink relate to its performance on the press and to the printing quality such as ink stability, transfer characteristics, mottle, squash, misting, dot gain, and so on. For lithographic print, the emulsification of ink is an important factor to determine the product. And also the rheological characteristics of the emulsified ink should be investigated. Thus, in this study, the effects of the changing molecular weight of rosin modified phenolic resin on the water-pickup ratio of neat inks were studied. And then rheological properties of neat inks and emulsified inks with changing molecular weight of rosin modified phenolic resin were analyzed by using rotational rheometer.