凹版印刷的定义.ppt

凹版印刷 Intaglio Printing Gravure Printing Rotogravure printing 推荐资源 欧洲凹印协会 美国凹印协会 凹印机：德国墨格公司 http://www.hcmoog.de 意大利赛鲁迪 http://www.cerutti.it 北人集团： 凹印印版：墨迪希戴怀勒 / 德国海尔 / 相关资源：博斯特公司 本章主要内容 1、凹版印刷的定义 2、凹版印刷的主要特点； 3、凹版印刷的市场领域； 4、凹版制版工艺； BASICS: The image carrier in the gravure process is generally a steel cylinder with a copper-plated surface in which small recesses, called cells, are made which carry the ink. The surface is normally then plated with hard chromium to improve its wearing properties. In the press, there is a printing unit for each cylinder. The surface of the rotating cylinder dips into an ink pan which fills the cells with ink (the inks for gravure printing are very fluid, whereas offset litho ink is paste-like). Surplus ink is then wiped off the cylinder surface by the squeegee action of the doctor blade, leaving ink only in the cells. The impression roller then presses the paper web onto the cylinder, and the ink transfers onto the paper. Gravure applies the ink in controlled doses from different sizes of cell. The larger the volume of the printing cells, the more ink is transferred and the stronger the tone which is reproduced by them. 凹版印刷的定义 凹版印刷的印版，印刷部分低于空白部分，所有的空白部分都在一个平面上，而印刷部分的凹陷程度则随着图像深浅不同而变化。图像色调深，印版上的对应部位下凹深。印刷时，印版滚筒的整个印版都涂满油墨，而后用刮墨装置刮去凸起的空白部分上的油墨，再放纸加压，使印刷部分上的油墨转移至纸上，从而获得印刷品。 Gravure printing is a very old process, the principles of which started in China in 100 AD: printing plates were prepared by hand using engraving tools. In the 16th century chemical etching was invented, whereby the image could be scratched into a resistant coating on the metal surface of a printing plate, and then etched into the metal using acid. By 1838 the principles of photography had been established and this challenged the printing industry to find ways to reproduce these direct images of the real world in a fast and accurate manner. In 1875 gravure was able to