JP2594519B2 - Offset rotary printing press - Google Patents

Description

The present invention relates to an offset rotary printing press.

[Problems to be solved by conventional technology and invention]

In general, an offset rotary printing press includes a paper feeding unit that feeds and supplies printing paper from a winding unit, a printing unit that performs offset printing, a drying unit that includes a heating device and a cooling roll for drying the printed paper, and a folding unit. And a paper discharge unit provided with a winding machine.

In such an offset rotary printing press, there is a problem that wrinkles occur on the printing paper due to uneven moisture evaporation in the drying section, and the quality is degraded. In order to prevent the occurrence of the wrinkles, various attempts have been made to make the heating of the printing paper uniform by a drying device, but to date no satisfactory solution has been obtained.

In addition, offset printing has a problem in that the gloss of the printed surface is insufficient compared with gravure printing.

The present invention has been made in view of the above problems, and eliminates wrinkles in offset printing. An object of the present invention is to provide an offset printing press capable of providing gloss comparable to that of gravure printing.

[Means for solving the problem]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, passed the printing paper having a wrinkle between a heat roller and a press roller having a smooth surface, and pressed the paper while heating to remove the wrinkle. The present inventors have found that they can be removed and that gloss can be imparted to the printed surface, and the present invention has been completed.

That is, the present invention is characterized in that a processing device including a heat roller having a smooth surface and a press roller for pressing a printed sheet against the heat roller is provided between the drying unit and the paper discharge unit. The gist is an offset rotary printing press.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to embodiments shown in the drawings.

FIG. 1 shows the overall schematic configuration of an offset printing press according to an embodiment of the present invention. In the figure, 1 is
A paper feeding unit for continuously feeding out the printing paper 3 from the printing paper winding 2; a printing unit 4 for performing offset printing on the printing paper 3; a drying unit 5 for heating and drying the printed paper 3; Is a cooling roller for cooling the paper 3, 7 is a silicon coater for applying silicon to the surface of the paper 3, and 8 is a folder. Since these are publicly known, detailed description is omitted.

Between the silicon coater 7 and the folding machine 8, there is provided a processing apparatus 10 which is a feature of the present invention. Processing device of the present embodiment
Reference numeral 10 includes a wrinkling roller 11 such as a crown roller or an expander roller, and a plurality of stages of heat rollers 12 and press rollers 13 disposed downstream of the roller. The heat roller 12 is a metal roller whose surface is mirror-finished and smoothed, has a hollow structure inside, and has a structure in which steam or hot water can be passed and heated. The press roller 13 is for uniformly pressing the sheet 3 against the surface of the heat roller 12 in the width direction, and is provided with an elastic material layer such as hard urethane rubber on the surface. The press roller 13 may also have a hollow structure as necessary, so that cooling water, hot water, or the like can pass therethrough. Pressing means such as a hydraulic cylinder (not shown) is connected to one of the heat roller 12 and the press roller 13.
The paper 3 is pressed by the press roller 12 and the press roller 13. Further, a driving device is connected to at least one of the heat roller 12 and the press roller 13, and is configured to be forcibly driven.

In the offset printing press having the above-described configuration, the printed paper 3 that has passed through the drying device 5 may have wrinkles due to the effect of moisture evaporation in the drying device 5. The paper 3 having the wrinkles is sent to the processing device 10 and supplied between the heat roller 12 and the press roller 13 in a state where the wrinkles are stretched by the wrinkle stretching roller 11. The heat roller 12 and the press roller 13 heat and press the paper 3 at the same time, and heat-fix the paper 3. Thus, the elbows are removed. At the same time, the paper 3 is heated and pressed, so that the paper 3 becomes smooth, and gloss is given to both the printed portion and the blank portion. Here, in order to effectively remove wrinkles, it is preferable that the heat roller temperature is 50 to 100 ° C., the press pressure is 10 to 150 kg / cm, and the surface hardness of the press roller 13 is about 90 to 95 ° in Shore D hardness. Also, heat roller
The larger the number of installations of 12 and press roller 13 (the number of presses),
Although it is effective in removing wrinkles and imparting gloss, the size of the equipment increases, so it may be appropriately determined in consideration of the required quality and equipment costs. In the illustrated embodiment, the wrinkle straightening roller 11 is disposed in front of the heat roller 12 and the press roller 13. However, depending on the paper, it is possible to perform good wrinkle removal without using the wrinkle straightening roller 11. Yes, the wrinkling roller 11 may be omitted.

In the above embodiment, the heat roller 12 and the press roller 13 provided in multiple stages are arranged on a straight line, but this arrangement can be variously changed. 2, 3 and 4 each show a modification thereof. In each of these figures, 3 is a sheet, 11 is a wrinkle-stretching roller, 12 is a heat roller, and FIG. 13
Indicates a press roller. In addition, 14 is a guide roller. The embodiment shown in FIGS. 2 to 4 has an advantage that a multi-stage press can be performed in a small space. The third
As shown in FIG. 4 and FIG.
When stacking 13, apply the pressing force between the rollers by placing the lowermost roller in a fixed position, making all other rollers movable, and pressing the uppermost roller downward by a pressing mechanism. And the pressing mechanism can be simplified.

FIG. 5 is a schematic side view showing an example of a pressing mechanism in the case where press rollers 13 are arranged above and below the heat roller 12, wherein the lowermost press roller 13 is held in a fixed position by a frame 15, and a driving device. (Not shown) and are forcibly driven. Intermediate heat roller 12 and top press roller
Each of 13 is held by supporting levers 17 and 18 which are swingably held by a frame 16, and a hydraulic cylinder 19 is connected to the uppermost supporting lever 17. Support levers 17, 18
An opening lever 20 is connected between the opening levers, and the opening lever 20 has an elongated hole so that the position with respect to one of the support levers 18 can be changed.
It has 20A. With this configuration, a pair of hydraulic cylinders 19 arranged on both sides of the roller can press between the rollers, and can open between the rollers. In the figure, reference numeral 21 denotes a water pipe joint, which is provided for supplying hot water to the heat roller 12 and cooling water to the press roller 13.

The following is an experimental result of actually measuring the effect of the processing apparatus 10.

(1) Experimental Example I Using the offset printing machine shown in FIG. 1, a sample A having a length of 10 cm was produced under the following conditions.

Use Paper: basis weight 85 g / m ² coated paper double-sided printed material processing apparatus 10 conditions: (number of used rollers) Press count: 2 Press pressure: 80 kg / cm press roller hardness: 92 ° C. (Shore D) pressing roller temperature: 46 ° C Heat roller temperature: 67 ° C As a comparative example, the length was measured without using the processing device 10.
A 10 cm sample B was prepared.

The profiles of the samples A and B were measured with a low stylus roughness meter, and the results shown in FIG. 6A (sample A) and FIG. 6B (sample B) were obtained. As is clear from these results,
10 greatly improved the wrinkles.

(2) Experimental Example II A sample was prepared under the following developing conditions.

Exhibition color condition: Sakariryou: monochromatic 0.125cc multi color 0.1 cc (R1 tester, 2 cuts) Drying: 0.99 ° C., 10 seconds Paper: the basis weight 85 g / m ² coated paper sample, the processor of the next press conditions 10 And the processing was performed while changing the number of presses.

Conditions of processing apparatus 10: Press pressure: 80 kg / cm Press roller hardness: 92 ° C (Shore D) Press roller temperature: 46 ° C Heat roller temperature: 67 ° C Measure the gloss value (%) of the processed sample (measurement) Container: Nippon Denshoku Co., Ltd. 60 ° -60 ° gloss meter). The results are shown in FIG. FIG. 8 shows the gloss change rate calculated from the measured data. FIG. 8 also shows the result of performing the same processing on a blank sheet and calculating the gloss change rate. As is clear from FIGS. 7 and 8, the printing unit,
The gloss is increasing for both blank and white paper.

〔The invention's effect〕

As described above, according to the present invention, since the heat roller and the press roller having a smooth surface are arranged between the drying section and the paper discharge section in the offset printing machine, even if the print paper has wrinkles, By passing the paper between the heat roller and the press roller and pressing it while heating, wrinkles can be removed, and high gloss and smoothness can be imparted to the printed part and blank paper part. This has the effect of enabling quality offset printing.

[Brief description of the drawings]

FIG. 1 is a side view showing a schematic configuration of an offset rotary printing press according to an embodiment of the present invention, FIG. 2, FIG. 3, and FIG. 4 are side views each showing a modification of the processing apparatus, and FIG. 6A and 6B are side views showing still another example, FIGS. 6A and 6B are diagrams showing profile measurement results of the sample, FIG. 7 is a graph showing the relationship between the number of presses and the gloss value, and FIG. It is a graph which shows the relationship of a rate. DESCRIPTION OF SYMBOLS 1 ... Paper feed part, 2 ... Winding, 3 ... Paper 4 ... Printing unit, 5 ... Drying device, 6 ... Cooling roller 7 ... Silicon coater, 8 ... Folding machine 10 ... Processing device , 11… Wrinkling roller 12… Heat roller, 13… Press roller

Claims (1)

(57) [Claims] 1. An offset rotary printing press comprising a paper feeding unit, a printing unit, a drying unit, and a paper discharging unit, wherein a heat roller having a smooth surface is provided between the drying unit and the paper discharging unit. An offset rotary printing press, comprising: a processing device including a press roller for pressing printed paper against the heat roller.