JPH07214932A - Planographic material made of stainless steel in newspaper offset printing - Google Patents

Abstract

PURPOSE:To enable repeated use and to achieve the conservation of labor and resources and the reduction of plate cost, in a planogrphic material used in newspaper offset printing, by constituting a non-image line part exclusive planogrphic material having no printing surface of a staianless steel single plate and applying surface treatment having hydrophilicity thereto. CONSTITUTION:An offset newspaper rotary press is quipped with planographic plates 3 each set so as to have printing width enabling simultaneous printing corresponding to four pages per a single surface with respect to one wound paper 6 and forming one printing part divided at every pages. Each of the planographic plates 3 are divided into four parts at every pages with respect to one plate cylinder 1. In this case, a non-printing surface exclusive planographlc material having no image line part is made of aluminum or stainless steel and the printing pressure thereof with an impression cylinder is set so as to become soft touch of about 0.02-0.05mm. By this constitution, the printing durability of stainless steel surface treatment and the durability of the gripper part applied to the plate cylinder 1 are enhanced to a large extent and repeated use is enabled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lithographic plate for use in newspaper offset printing, and a lithographic plate for exclusive use in a non-image area on a non-printing surface and a lithographic plate for exclusive use without winding running paper.

[0002]

2. Description of the Related Art Lithographic materials used in newspaper offset printing are
The aluminum PS plate is used, and like newspaper printing, the paper width is printed with 4 pages on one side of the printing plate with one printing machine.
In order to print the printing section on another printing machine out of the four pages of the color printing course such as the color printing course, we used an aluminum PS plate that does not have an image area, commonly known as a waste plate. This plate has good hydrophilicity and repels ink, and this lithographic material is used as the lithographic material for the non-printed surface.
However, because it is made of aluminum, the printing durability of the surface sand to maintain hydrophilicity and the grip strength to be hung on the plate cylinder are
The limit is about 150,000 to 200,000 copies, which are discarded at the end of printing.

[0003]

[Problems to be Solved by the Invention] The number of lithographic materials that do not have such a printing surface, such as present or future colorization, is increasing more and more. However, the cost of disposal is ever increasing. By making it possible to repeatedly use the lithographic material used for such a non-printing surface, not only resource saving and labor saving but also a large cost reduction of consumables can be achieved.

[0004]

[Means for Solving the Problems] In order to achieve the above object, the planographic material is made of stainless steel so as to maintain hydrophilicity.
The stainless steel surface is grained. The thickness of the planographic material is usually 0.3 ^{mm because} the printing pressure bite width of the plate and impression cylinder is 0.15 ^mm , but it is 0.2 ^mm due to the durability and handleability of graining. It should be thick and can be repeatedly used as a non-printing planographic material with a soft kiss touch on the impression cylinder. On the plate surface without the winding running paper, in order to protect the plate cylinder and prevent ink from rising to the spot cylinder, a 0.1 ^mm thick stainless lithographic plate that does not come into contact with the impression cylinder is used. It can be used repeatedly.

[0005]

[Function] The lithographic material for the non-printing surface, which does not have an image area, is made of aluminum instead of stainless steel, and the printing pressure with the impression cylinder is a soft touch of about 0.02 to 0.05 ^mm. Therefore, it can be used repeatedly by greatly increasing the printing durability of the stainless steel surface treatment and the durability of the gripping part to be hung on the plate cylinder.

[0006]

EXAMPLE FIG. 1 is a schematic view of the structure of a printing section of an offset newspaper press. This is because the planographic plate is wrapped around the plate cylinder, the image area receives ink from the ink roller, and the non-printing surface is supplied with water from the watering roller, repels the ink and transfers it to the blanket cylinder. It is printed on the take-out paper.

FIG. 2 shows that the offset newspaper press has a printing width of one roll and can print four pages on one side simultaneously.
A lithographic printing plate is a single printing unit that is divided for each page and is capable of printing 8 pages on both sides.

Here, the lithographic printing plate is divided into four parts for each page for one cylinder, but when a part of the printing plate such as a color course passes through another printing machine, it has no image area. A special planographic material is required, and since the plate surface repels the ink, it is necessary to have only water supplied. Currently,
Although it is made of aluminum, it is made of stainless steel because of its printing durability and strength.

FIGS. 3 and 4 show the press-in thickness of the printing cylinder between the plate cylinder on which the lithographic printing plate is applied and the blanket cylinder to be transferred, and FIG. It has a thickness of 3 ^mm, and since it has an image area to be printed, the bite thickness is 0.15 ^mm . Is
Due to the structure to repel ink, the thickness of the plate is often 0.2 ^mm.
The ▼ can be made approximately 0.05 ^mm , and by adopting a stainless lithographic plate, it has printing durability and strength several ten times that of aluminum and can be used repeatedly.

FIG. 5 is a standard planographic dimension drawing of a rotary machine manufacturer with one page width and two pages. This lithographic plate is made of stainless steel and has a thickness of 0.2 ^mm , so that it can be repeatedly used. Further, the lithographic plate to be used in the part where there is no winding running paper has a thickness of 0.1 ^mm so as not to come into contact with the blanket cylinder.

The embodiments of the present invention have been described in detail above.
Since the lithographic plate on the non-printing side of newspaper offset printing is made of stainless steel, it can be used repeatedly, saving labor,
It is possible to save labor, save resources, and significantly reduce printing costs.

[0012]

According to the present invention, the following effects occur. 1. Improve productivity and work efficiency. 2 Reduction of human labor. 3 Improvement of economic effect.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a newspaper offset printing machine.

FIG. 2 is a projection view of a plate cylinder and a blanket cylinder of the printer body.

FIG. 3 is a schematic basic sectional view of a printing transfer pressure in an aluminum lithographic plate with respect to a blanket cylinder.

FIG. 4 is a schematic basic cross-sectional view of a printing transfer pressure in a stainless lithographic plate with respect to a blanket cylinder.

FIG. 5 is a standard dimensional drawing of a planographic material for a newspaper press.

[Explanation of symbols]

1 ... plate cylinder 2 ... blanket cylinder 3 ... planographic plate 4 ... ink roller 5 ... watering roller 6 ... winding run paper 7 ... aluminum planographic material 8 ... stainless planographic material 9 ... printing transfer press-in width (0.15 ^mm ) 10 ... Printing transfer press-in width (0.05 ^mm )

Claims (2)

[Claims] 1. A single plate made of stainless steel is used as a lithographic material for non-image areas having no printing surface, and a surface treatment having hydrophilicity is applied thereto. 2. A plate cylinder without a winding run paper, which is a super thin type lithographic plate of stainless single plate which is non-contact with the impression cylinder.