Digital stencil printing process and precautions

According to the surface morphology of the printing plate, the printing can be divided into four categories: relief printing, gravure printing, lithographic printing, and stencil printing. In recent years, there has been no printing without printing plates. The representative of screen printing is screen printing. In addition, there are steel plates and printing plates. Now that printing has been changed to the thermal digital plate making mode, a printing and printing machine has emerged. Recently, we have also introduced simple copy presses that can connect personal computers and networks and operate in a similar manner to copiers.

Digital hole printing

The digital stencil printing machine is easy to operate. Its greatest feature is that the more copies are printed, the lower the running cost. For example, if the "Preport" digital stencil printing machine produced by Ricoh in Japan has more than 100 copies, its printing costs are almost the cost of paper. Because digital stencil printing has the characteristics of energy saving, it is suitable for use in small units such as schools, bookstores, government agencies, hospitals, and retail stores.

The following will introduce the current status of digital stencil printers, the base papers being developed (base papers for printing plates), and the development direction of digital stencil printing.

Change of printing and plate making methods

The printed copy was printed in 1894. The method was to lay wax on a sheet of iron and write it with a stylus to form a fine hole to complete the plate making. The prepared version of the wax paper was put on the frame of the manual printing machine, and the ink was used again. The rollers roll the ink through the wax paper onto the paper. This type of transcription has been adopted by government agencies, universities and news agencies during the war in a simple structure and light printing.

As with other printing technologies, stencil printing has evolved from the earliest hand stencils to the original version of the typing mechanism and to the discharge stencil. Although the discharge type stencil printing plate produces hydrogen chloride gas, it has an epoch-making progress due to its feature of being able to make plates by photoelectrically reading originals. The flash plate-making method introduced in 1980 shortened the plate-making time, and there was no air pollution. It soon became popular. However, the disadvantage of this method is that it can only be used for ink, photos cannot be made, and the original may be damaged.

In 1986, Ricoh introduced the PreportSS-880, which uses a digital thermal plate making method to make up for the deficiencies of the original method. At the same time, it absorbed the advantages of digital plate making technology. This type of plate making method has been used up to now. This digital stencil printer has two significant features.

(1) The plate-making machine and the printing press are integrated into one, the operating conditions are improved, and the quality is improved.

(2) Due to the use of thermal digital platemaking technology, the picture quality is improved and digital picture processing technology can be used.

Digital stencil printing machine overview

The digital stencil printer configuration generally consists of the following six parts.

1 scanning section

A device for reading the original text information, ie scanning the original, optically collecting the signal, and converting it into an electrical signal.

2 imaging section

According to the signal from the scanning portion, the thermal head is thermally perforated by the thermal head on the reel-shaped stencil sheet, and a graphic version is produced. After the stencil is cut, the printing roller is supplied to the printing cylinder.