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Volume 25, Issue 9
Displaying 1-11 of 11 articles from this issue
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Humio INABA1997 Volume 25 Issue 9 Pages 619-620
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSDownload PDF (1118K) -
Takashi KITAMURA1997 Volume 25 Issue 9 Pages 621-624
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSLaser thermal transfer printing was first investigated in the early 1970's but dropped in favor of more compact and efficient thermal printers that employ small thermal print elements. Recently, several types of laser thermal printing using a high power laser diode were developed to make a color proofing and plate-making for offset lithography in graphic art. In this paper, several types of laser thermal printing technologies are introduced. The laser diode irradiation is absorbed as heat in the thermal media which results in local physical change such as melting, sublimation, ablation and a high definition image is formed by material transfer from a donor sheet to receiving sheet. A high definition image is obtained easily because a laser light can be focused to small spot on a donor sheet. A laser thermal printing is a convenient for achieving a high definition image.View full abstractDownload PDF (732K) -
Takashi KITAMURA1997 Volume 25 Issue 9 Pages 625-628
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSFor development of computer-to-plate direct exposure system, it is necessary to develop a dry and high definition recording process connected to the computer system. In the wax melt-type laser thermal transfer printing, the laser diode irradiation is absorbed as heat in the thermal transfer ribbon that results in local melting and transfer of the ink to the receiving sheet. In this research, the ink image was transferred to the paper and an aluminum plate by laser heating technology for making the high definition image and offset printing plate directly. The fundamental characteristics such as the shape of printed pixel, printing energy and optimization of printing condition were discussed in the melt-type thermal printing by laser heating.View full abstractDownload PDF (692K) -
Yoshiaki ODAI, Takashi TAKEDA, Ryoji ARIMA, Masatoshi KATOH1997 Volume 25 Issue 9 Pages 629-633
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSIn laser dye thermal transfer printing using a focused laser beam as the heat source, continuous-tone images with very high resolution are obtained. However, the printing speed is relatively low compared to that of thermal head printing, in which a large number of dots can be recorded simultaneously. To shorten the printing time, a high-power Nd:YAG laser is used for the light source in our printing system. Printing characteristics with a short pulse, of the order of 1μsec, are evaluated in this printing system. As a result, continuous-tone printing with a short pulse of 2μs is feasible when laser power is 1.0W, indicating a significant advance in printing speeds. The transfer efficiency as a function of pulse width has a peak that can be observed. Good halftone printing of high definition image with 400lpi is also performed using this system.View full abstractDownload PDF (1161K) -
Tetsumi ENOMOTO1997 Volume 25 Issue 9 Pages 634-638
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSKodak and other companies use Laser Thermal Printing (LTP) for digital color proofing, computer to plate preparation, and other graphic art applications with highest quality results. This paper addresses the questions a) why does LTP work so well ? and b) what can we expect in the future ? The LTP process consists of focusing the beam of a diode laser onto a coating containing an infra red absorber and either a dye or a thermally sensitive reagent. The infrared dye absorbs the diode laser beam and converts the energy to heat, which causes the dye to transfer, or a chemical reaction in the coating. LTP images have very high resolution because the laser spot can be focused almost to the diffraction limit. Edges are very sharp because the temperature drop at the edge of the beam is steep. An important factor in the application of LTP to graphic arts is that all the amplification is electronic and the results are therefore predictable, reliable and robust. These are essential qualities that will determine how far the printing industry can change from a skilled art and craft to an automated and standardized process.View full abstractDownload PDF (818K) -
Wilhelm H. AHRENS1997 Volume 25 Issue 9 Pages 639-642
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSSince several years the PrePress and Printing Industry is looking for advanced solutions to improve the productivity and quality of the printing process. The key word which is used within the last years is Computer to Plate or CTP. Several CTP installations have been done worldwide. This article explains the benefits and requirements of the user and technical details of the plate-laser system which is used in the Gutenberg plate exposing machine developed by Linotype-Hell.View full abstractDownload PDF (672K) -
Takane NISHINO, Kan-iti FUJII1997 Volume 25 Issue 9 Pages 643-645
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThere are various inquiries for the small scale full color printing industry, i.e. higher quality printing, shortening of the date of derivery, cost down, care for environmental pollution, data transportation, and etc. Quickmaster DI equipped with a direct imaging technology has realized a direct digital full color printing and is expected to offer a solution for these problems. The detail of this new printing system is described in this paper.View full abstractDownload PDF (1067K) -
Kazuyuki OKADA, Tetsuya YAMADA, Hiroshi TSUBAKIHARA, Akihiko SAKAMOTO1997 Volume 25 Issue 9 Pages 646-649
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe longitudinal distribution of fluorescence from low-OH silica fiber was experimentally observed under KrF excimer laser delivery. The fluorescent region was localized near the input end of the fiber at initial stage of laser delivery and shifted to the output end with increasing the number of laser pulses. As the fluorescent region reached the output end of the fiber, transmitted laser light was remarkably enhanced. This enhancement would be induced by the KrF-laser-bleaching of the defects in the fluorescent region. The photo-bleaching effect could be expected to be one of the remedies for the reduction in delivery efficiency of the silica fiber reported before.View full abstractDownload PDF (624K) -
Masayuki JYUMONJI, Koji SUGIOKA, Hiroshi TAKAI, Hideo TASHIRO, Koichi ...1997 Volume 25 Issue 9 Pages 650-653
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe characterization of structural and chemical properties of stainless steel (SUS) 304 modified by laser implant-deposition (LID) of Si using a KrF excimer laser has been investigated. The cross sectional transmission microscope (X-TEM) observation and X-ray diffraction (XRD) measurement suggest that LID technique can form the top of the Si deposited layer and the interdiffusion layer between Si and SUS304. In addition, the compounds between Si and Fe such as Fe3Si and FeSi2 are formed in the interdiffusion layer. Under the thermal treatment of 600°C for 1 hour in the N2 atmosphere, the interdiffusion coefficient is as small as - 2.0 × 10-15cm2/s, which is six orders of magnitude smaller than that in the SUS304 deposited on Si by electron beam evaporation. Additionally, the corrosion property of LID-modified SUS304 against an HCl aqueous solution has no remarkable change after the thermal treatment in spite of the deterioration of the characteristics in the EB-evaporated SUS304. Thus, the LID-surface modification can provide the high corrosive properties even if the exposed after the thermal treatment.View full abstractDownload PDF (735K) -
Fumito KITATANI, Kan-iti FUJII1997 Volume 25 Issue 9 Pages 654-657
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSA chemical oxygen iodine laser (COIL) is an efficient laser which generates high power 1315nm light which is near minimum loss wavelength of transmission of the quartz optical fiber. The excited source of COIL are the O2(1Δ) molecules. The H2O vapor is a strong quencher of O2(1Δ), moleculestherefore it is necessary to remove it for efficient operation. A cold trap is generally used for this. The trap's temperature is very important. In this paper, the dependance of quenching rate of O2(1Δ) molecules upon the trap temperature is shown. The quenching rate decreases with the trap's temperature. However, the decreasing quenching rate begins to saturate at - 50°C, and it begins to increase under - 60°C.View full abstractDownload PDF (629K) -
Yoshio CHO1997 Volume 25 Issue 9 Pages 658-664
Published: September 15, 1997
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSDownload PDF (1159K)
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