JP2000052528A - Method for drying printing surface of perfecting sheet- fed offset printer and its drying mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To offset print one or a plurality of colors on both front and rear surfaces of a sheet by one time sheet conveying by drying printing surfaces of the front and rear surfaces of the sheet immediately after the printings are finished. SOLUTION: A perfecting drying mechanism W having an infrared dryer or an ultraviolet dryer is arranged above a surface printing impression cylinder S of the perfecting sheet-fed offset printer, and a rear surface printing drying mechanism T similarly having an infrared dryer or an ultraviolet dryer is arranged. Both the printing surfaces are dried immediately after printing of front and rear surface printing is finished via these perfecting drying mechanisms W and T. Thus, one or a plurality of colors can be offset printed on both front and rear surfaces of the sheet by one time sheet conveying.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided printing sheet-fed offset printing press. More specifically, one-color or plural-color offset printing can be performed on both sides of a sheet in a single pass. The present invention relates to a method and mechanism for drying a printing surface of a simple printing machine.

[0002]

2. Description of the Related Art A conventional double-sided printing sheet-fed offset printing press includes:
There is one developed and disclosed by the present applicant (JP-A-6-336003). This conventionally known double-sided printing sheet-fed offset printing press is provided with a blanket cylinder, a plate cylinder, and an inking mechanism at the upper and lower portions of each impression cylinder provided with a paper holding claw to form a front printing unit and a back printing unit. Then, by connecting the front and back printing units by each impression cylinder, the printing can be alternately performed on the front and back surfaces of the sheet because the impressions are sequentially transferred by each impression cylinder of the front and back printing units. The method is as shown in FIGS. 2 to 4. That is, as shown in FIG. 2, the sheet P piled on the feeder main body 1 is supplied to the printing unit A via the feeder board 2, the swing device 3, and the transfer cylinder 4, as shown in FIG. The sheet P is printed on both sides of the sheet P. The printing unit A includes one front printing unit 5a and one back printing unit 6a. The front printing unit 5a includes a blanket cylinder 7a, a plate cylinder 9a, and an impression cylinder 11a having the same diameter as the plate cylinder 9a. An inking mechanism 13a, a water supply mechanism 15a, etc., and a blanket cylinder 7a
It is formed by connecting the plate cylinder 9a, the inking mechanism 13a, and the water supply mechanism 15a. Also, the back side printing unit 6a
Is a blanket 8a, an impression cylinder 12a having the same diameter as the plate cylinder 10a, an inking mechanism 14a,
It comprises a water supply mechanism 16a and the like.
It is formed by connecting a blanket cylinder 8a, a plate cylinder 10a, an inking mechanism 14a, and a water supply mechanism 16a to a lower portion of the section a.

As described above, the conventional double-sided printing sheet-fed offset printing press has a front printing unit 5a and a back printing unit 6a.
In this case, the impression cylinders 11a and 12a constituting the printing units 5a and 6a on the front and back sides are connected in the horizontal direction, and the line connecting the impression cylinder axes is horizontal. Impression cylinders 11a and 12 so as to be substantially linear in
a may be connected.

As shown in FIG. 3, a sheet P piled on a feeder main body 1 is fed to a printing section B via a feeder board 2, a swing device 3, and a transfer cylinder 4 as shown in FIG. 4 sheets each on both sides of the sheet P
It is to be printed in color. The printing unit B includes four front printing units 5a to 5d and four back printing units 6a to 6d.
6d, and the first to fourth color surface printing units 5a to 5d are the same as the surface printing unit 5a described above.
The back printing units 6a to 6d for the fourth color are the same as the back printing unit 6a described above and the impression cylinders 11a and 12a are the plate cylinders 9a and 1
It is formed similarly except that it has a diameter twice as large as 0a.

[0005] As described above, the conventional two-sided four-color printing sheet-fed offset printing press includes the front side printing units 5a, 5b, 5c, and 5d.
And the back side printing units 6a, 6b, 6c, 6d, for example, the first color front side printing unit 5a, the first color back side printing unit 6a, and then the second color front side printing unit 5b. In this case, the printing units 5a to 5d, 6a to 6
The impression cylinders 11a to 11d and 12a to 12d constituting d are connected in the horizontal direction, and as shown in FIG. However, the impression cylinders 11a to 11d and 12a to 12d may be connected so that a line connecting the impression cylinder axes is substantially linear in the horizontal direction.

According to the single-sided, four-color, sheet-fed offset printing machine shown in FIG. The sheet P is printed and printed in four colors on both sides of the sheet P. The front side printing unit 5a includes a blanket cylinder 7a, a plate cylinder 9a and an impression cylinder 11a having the same diameter as the plate cylinder 9a, an inking mechanism 13a, a water supply mechanism 15a, and the like.
It is formed by connecting the plate cylinder 9a, the inking mechanism 13a, and the water supply mechanism 15a. The back side printing unit 6a includes a blanket cylinder 8a and a plate cylinder 10a similarly to the front side printing unit 5a.
The press drum 12a includes an impression cylinder 12a, an inking mechanism 14a, a water supply mechanism 16a, and the like having the same diameter as the plate cylinder 10a.
It is formed by connecting the inking mechanism 14a and the water supply mechanism 16a. Then, behind the impression cylinder 11a of the front printing unit 5a, the impression cylinder 12a of the back printing unit 6a is provided.
Are connected in the horizontal direction to form a first color front / back printing unit G as one unit, and second to fourth color front / back printing units H to J are configured similarly to the first color front / back printing unit G. Is done.

As described above, the two-sided four-color printing sheet-fed offset printing press has an intermediate cylinder 17. 1 provided with two first-color to fourth-color front and back printing units G to J between each unit.
8 are connected in the horizontal direction. In this case, the cylinders of the impression cylinders 11a to 11d and 12a to 12d and the six intermediate cylinders 17 and 18 that constitute the printing units 5a to 5d and 6a to 6d on the front and back sides, respectively. The first to fourth color front and back printing units G to J are connected so that the axis is substantially linear in the horizontal direction. However, the first to fourth color front and back printing units G to J may be connected so that the line connecting the trunk axis is substantially linear in the horizontal direction. With the above configuration, the sheet P is transferred from the transfer cylinder 4 to the impression cylinder 11a of the front and back printing unit 5a constituting the first color front and back printing unit G.
The first color printing is performed on the front surface, and then transferred to the impression cylinder 12a of the back surface printing unit 6a, and the first color printing is performed on the back surface. Thereafter, the sheet P is sequentially sent to the second color front and back printing unit H via the two intermediate cylinders 17 and 18 and further to the third color and fourth color front and back printing units I and J, and each sheet is sent to the second color front and back printing unit I / J. The second to fourth colors are printed on the front and back surfaces, respectively.

Reference numeral 20 denotes a delivery cylinder connected to the last impression cylinder 12d, 21 denotes a sprocket, 22 denotes a delivery chain with a gripper driven by the sprocket 21, and the sheet P after printing is the last. Delivery chain 2 with gripper from impression cylinder 12d of
2, the paper is discharged onto the paper discharge table 23.

[0009]

In such a conventional double-sided sheet-fed offset printing press, since the printing surface is pressed against the backside impression cylinder in a wet state immediately after printing on the front side, the surface of the impression cylinder is made uneven. And wearing special jackets. As a result, the cost increases due to special treatment,
Maintenance such as cleaning takes time, and if the unevenness of the impression cylinder surface rubs, it will cause printing trouble,
Further, there is a problem that the printing quality is deteriorated due to the unevenness.

Further, since the printed surface passes through the delivery in a wet state, it is necessary to use a special delivery designed so that the printed portion on the back surface does not touch the paper guide or the suction wheel. As a result, the structure becomes complicated and the cost increases, and even if the paper flaps a little, back flaws will occur, so you will have to use nerves for air adjustment etc.
Since printing cannot be performed at the part where the paper is sucked by the suction wheel, there is a problem that the printing pattern must be restricted, and the position of the suction wheel must be adjusted according to the pattern.

[0011]

SUMMARY OF THE INVENTION The present invention has been developed in order to solve the above-mentioned problems. One side or the other side of a sheet is printed with one color or a plurality of colors by a single threading. In a double-sided sheet-fed offset printing method for performing offset printing, a method for drying a printed surface in a double-sided sheet-fed offset printing press, characterized by drying the front and back printing surfaces immediately after each printing is completed. In addition, the drying method is a drying method of a printing surface, which is a drying method by heating drying or a photochemical reaction.

A front printing unit and a back printing unit are formed by providing a blanket cylinder, a plate cylinder, and an inking mechanism respectively on the upper and lower parts of each impression cylinder, and the printing units on the front and back sides are connected by the impression cylinder. In a two-sided printing sheet-fed offset printing press, a drying mechanism for front-side printing is disposed on the impression cylinder for front-side printing, and a drying mechanism for back-side printing is disposed on the impression cylinder for rear-side printing,
The present invention provides a drying mechanism for a printing surface in a double-sided printing sheet-fed offset printing machine, characterized in that both printing surfaces are dried immediately after printing of the front printing and the back printing via the double-side drying mechanism. The purpose of the present invention is to provide a drying mechanism for a printing surface, wherein the mechanism is an IR (infrared) dryer or a UV (ultraviolet) dryer.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention relates to a double-sided sheet-fed offset printing method for performing one-color or multiple-color offset printing on each of the front and back surfaces of a sheet in a single pass of paper. This is a method of drying the printed surface of the front and back surfaces immediately after the end of each printing, and the drying method is a drying method by heating or photochemical reaction. By adopting a double-sided sheet-fed offset printing method in which one-color or plural-color offset printing is performed on both sides of the front and back surfaces of paper, all the problems that have conventionally occurred can be solved.

Further, according to an embodiment of the present invention, a blanket cylinder, a plate cylinder, and an inking mechanism are respectively provided on the upper and lower portions of each impression cylinder to form a front side printing unit and a back side printing unit. In a double-sided printing sheet-fed offset printing press connected by an impression cylinder, a drying mechanism for front-side printing is arranged on the impression cylinder for front-side printing, and a drying mechanism for back-side printing is arranged on the impression cylinder for back-side printing. The printing mechanism is a printing surface drying mechanism for drying both printing surfaces immediately after printing of the front side printing and the back side printing via the drying mechanism, and the drying mechanism is an IR (infrared) drying device or a UV (ultraviolet) drying device. Therefore, if this drying mechanism is provided in a conventional double-sided sheet-fed offset printing press that performs one-color or plural-color offset printing on both the front and back surfaces of a sheet in a single pass of the conventional sheet-passing method, this has conventionally occurred. Problems Hand can be solved.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the method and mechanism for drying a printing surface of a double-sided printing sheet-fed offset printing press according to the present invention are as follows: a drying mechanism W for front and back printing is disposed above an impression cylinder S for front printing; A drying mechanism T for printing on the back side is provided below the impression cylinder R for printing.
Is arranged. The embodiment shown in this figure shows a case where a drying mechanism is attached to the conventional single-color double-sided sheet-fed offset printing press shown in FIG. Therefore, when a drying mechanism is attached to the conventional multi-color double-sided sheet-fed offset printing press shown in FIGS.

In this embodiment, an IR (infrared) drying device is used as a printing surface drying mechanism. The drying IR drying device is a device for heating and drying a printing surface, a plate surface, and the like by infrared rays. In general, a number of infrared lamps are arranged and radiated toward the printing surface with radiation heat about 10 times that of sunlight. At that time, the heat transfer efficiency of the infrared lamp is relatively good, and a large amount of the heat is absorbed and transmitted to the place where the ink is applied. Further, a UV (ultraviolet) drying device is used for the printing surface drying mechanism of the present embodiment. This UV drying device is
An ink that is instantaneously cured and dried by irradiation with ultraviolet light, and is composed of a prepolymer having a radical polymerizable double bond, a monomer, and a photopolymerization initiator that generates radicals by ultraviolet light. In particular, no solvent, low odor,
Because of its advantages such as instant drying, it is used for printing on food packaging paper containers, beverage cans, plastic materials, and the like.

As described above, according to the present invention, a conventional double-sided printing sheet-fed offset printing press is provided with a drying mechanism for drying a printing surface. [Technology], the description is omitted here. The drying device used in the present invention is an IR (infrared) drying device and a UV drying device.
(Ultraviolet) dryers, each of which is only a general and representative one, and the same operation and effect can be obtained with other dryers.

[0018]

According to the present invention, there is provided a double-sided sheet-fed offset printing method for performing one-color or plural-color offset printing on each of the front and back surfaces of a sheet in a single threading operation. A method of drying a printing surface for drying a printing surface of a front surface and a back surface, and the drying method is a method of drying by heating or a photochemical reaction, and further, a blanket cylinder, a plate cylinder, An inking mechanism is provided to form a front printing unit and a back printing unit, and the front and back printing units are connected by an impression cylinder. A drying mechanism is provided, and a drying mechanism for back printing is provided on the impression cylinder for back printing, and both printing surfaces are simultaneously and mutually dried immediately after the printing of the front printing and the back printing via the double-side drying mechanism. Print surface Since the drying mechanism is an IR (infrared) drying apparatus or a UV (ultraviolet) drying apparatus, it is possible to solve all the problems that have conventionally occurred, and to achieve the following specific effects. Have.

A. In a conventional double-sided printing sheet-fed offset printing press, immediately after printing on the front surface, the printing surface is pressed against the impression cylinder on the back surface in a wet state, so that the surface of the impression cylinder is roughened or a special jacket is attached. Cost due to special treatment, it takes much time for maintenance such as cleaning, and friction on unevenness on the surface of the impression cylinder causes printing trouble, and printing quality deteriorates due to the unevenness However, according to the present invention, all of these problems can be solved.

(2) Since the printed surface passes through the delivery in a wet state, it is necessary to use a special delivery designed so that the printed portion on the back side does not touch the paper guide or the suction wheel. As a result, the structure becomes complicated and the cost increases, and even if the paper flaps a little, back flaws will occur, so it will be necessary to use nerves for air adjustment etc. Restrictions are also required for the pattern of printing, and problems such as the need to adjust the position of the suction wheel and the like according to the pattern have occurred. According to the present invention, all of these can be solved. .

[Brief description of the drawings]

FIG. 1 is an explanatory schematic diagram showing a method for drying a printing surface and a drying mechanism in a double-sided printing sheet-fed offset printing press of the present invention.

FIG. 2 is a schematic diagram illustrating a conventional double-sided printing sheet-fed offset printing press.

FIG. 3 is a schematic diagram showing a conventional double-sided printing sheet-fed offset printing press.

FIG. 4 is a schematic diagram showing a conventional double-sided printing sheet-fed offset printing press.

[Explanation of symbols]

5a, 5b, 5c, 5d Front side printing unit 6a, 6b, 6c, 6d Back side printing unit 7a, 7b, 7c, 7d Front side printing unit 5
a to 5d blanket cylinders 8a, 8b, 8c, 8d Back printing unit 6
a to 6d blanket cylinders 9a, 9b, 9c, 9d Surface printing unit 5
a to 5d plate cylinders 10a, 10b, 10c, 10d Backside printing unit 6
a to 6d plate cylinders 11a, 11b, 11c, 11d Impression cylinders 12a, 12b, 12c, 12d Impression cylinders 13a, 13b, 13c, 13d Surface printing unit 5
a to 5d inking mechanism 14a, 14b, 14c, 14d Backside printing unit 6
a to 6d inking mechanism W Front-side printing drying mechanism T Back-side printing drying mechanism S Front-side printing impression cylinder R Back-side printing impression cylinder

Claims (4)

[Claims] 1. A double-sided sheet-fed offset printing method for performing one-color or multiple-color offset printing on each of the front and back surfaces of a sheet in a single threading operation. A method for drying a printing surface in a double-sided printing sheet-fed offset printing press, characterized by drying the printing surface. 2. The method for drying a printing surface in a double-sided sheet-fed offset printing press according to claim 1, wherein the drying method is a drying method by heating or a photochemical reaction. 3. A front printing unit and a back printing unit are formed by providing a blanket cylinder, a plate cylinder, and an inking mechanism respectively at the upper and lower portions of each impression cylinder, and the printing units on the front and back sides are connected by the impression cylinder. In the double-sided printing sheet-fed offset printing press, a drying mechanism for front-side printing is arranged on the impression cylinder for front-side printing, and a drying mechanism for back-side printing is arranged on the impression cylinder for back-side printing. A printing surface drying mechanism in a double-sided printing sheet-fed offset printing press, wherein both printing surfaces are dried immediately after printing of front-side printing and back-side printing. 4. The drying mechanism for a printing surface of a double-sided sheet-fed offset printing press according to claim 3, wherein the drying mechanism is an IR (infrared) drying device or a UV (ultraviolet) drying device.