JP4264455B2 - Printing method by offset printing machine and offset printing machine - Google Patents

Description

  The present invention relates to a newspaper rotary press, a printing method using an offset printing press, and an offset printing press suitable for printing on a newspaper rotary press.

In recent years, the print quality of patterns such as color photographs has been greatly improved. This has improved printing technology and improved printing ink quality, but also greatly contributed to improving the quality of printing paper. In other words, when printing paper is limited as in newspaper printing, for example, the required printed picture quality may not be sufficiently obtained.
That is, newsprint used in a newsprint press has a lower whiteness (or lightness) than other printing papers. In addition, in the case of newsprint paper, lightweight paper with a low basis weight is used in consideration of transportability, and further weight reduction of paper has been promoted in accordance with the trend of increasing the number of pages. The opacity of the paper is also reduced compared to other printing papers.

  The low whiteness and opacity of newsprints in this way do not greatly interfere with the printing of articles, but in the case of color printing, such as color photographs, and there is a high-line printing area to a certain extent. In some cases, it will cause problems. In other words, white in color printing depends on the color of the paper itself. Therefore, if the whiteness of the paper is low, at least in this white portion, the required color tone will be different. Also, if the paper has low opacity, the back side of the printed portion of the high image line is likely to be exposed.

Therefore, in the case of newspaper printing, as described above, a paper with high whiteness or a high opacity is used for a portion that cannot meet the demand for a white portion with normal newsprint paper or a portion that is likely to cause back-through. It corresponds by replacing.
However, in the case of news paper with high whiteness, white paper is finely coated and coated at the papermaking stage in order to improve the whiteness of newsprint, making it expensive and increasing costs. Invite. In particular, when the paper is replaced as described above, for example, the back side that does not require paper replacement or the portion that does not require paper replacement, such as articles, even on the same side, is also expensive and has high whiteness. Become.

On the other hand, Patent Document 1 discloses a paper-like photo printing location when characters and photographs are printed on the same paper using a paper with low smoothness, opacity and whiteness such as newspaper. In addition, a technology has been proposed that prints pictures more clearly while using newspaper, etc., by printing after partially processing a paper surface improver that increases smoothness, opacity, and whiteness with a printing method. Yes.
Further, Patent Document 2 discloses that a newspaper having a low whiteness is processed by placing a white ink in advance on a place where a photograph or an advertisement is printed, and then performing printing. Techniques have been proposed for printing advertisements, photographs, etc. in the required color tone while using paper.
Japanese Examined Patent Publication No. 45-25649 Japanese Patent Laid-Open No. 2-117877

  However, in the techniques of Patent Documents 1 and 2, although there is a possibility that the cost can be reduced as compared with the case where the printing paper is partially replaced with one having high whiteness, these techniques are preliminarily offline in advance. However, there is no point in processing time and processing cost because it is a new burden, and it is necessary to do it online, but it has not yet been put into practical use online. This is because the paper surface improver and white ink do not dry easily when processed with a paper surface improver or white ink on the paper (web) in the pre-printing stage. This is thought to be due to problems such as turbidity in the ink and the print quality that should be improved.

  Note that the drying of the paper surface improver or white ink referred to here means that at least the ground surface treatment agent on the paper surface is mixed with the printing ink transferred in the printing unit when printing is started in the printing unit of the printing press. This means that the printing ink does not cause turbidity. The solvent component contained in the surface treatment agent does not necessarily need to be completely removed from the surface treatment agent layer on the printing paper by penetrating into the printing paper or volatilizing in the atmosphere.

  In other words, normally, in offset printing such as newspaper printing, each ink color may overlap, but the overlap of the ink is not large, so there is no big problem even if the next ink is placed on the ink not drying sufficiently, If the ink is overprinted after printing the surface improver or ink with solid printing or high image coverage, if the ink is not dried completely after the first printed surface improver or ink is overprinted, the next printed ink will be printed. Since the improver and the ink are mixed to cause turbidity, the printed color tone is greatly reduced. In particular, when white ink and other inks are mixed, the hue changes greatly.

  The present invention has been devised in view of such problems, and performs surface treatment with a ground treatment agent on low-whiteness printing paper or the like, such as newsprint paper, and turbidity occurs in printing ink due to the ground treatment agent. It is an object of the present invention to provide a printing method using an offset printing machine and an offset printing machine, which can improve the printing quality in such a manner.

In order to achieve the above goal, a printing method using an offset printing machine according to the present invention is a printing method using an offset printing machine, and includes a base treatment agent supply step of supplying a base treatment agent to a printing surface of a printing paper, and the base treatment agent and drying step of drying the ground processing material supplied to the printing surface by the supply step, and a printing step of performing the offset printing on dried the printing paper by the drying step, the underlying The treatment agent is a liquid having a viscosity of 0.01 to 50 P at a temperature of 20 ° C. under atmospheric pressure, and contains a solvent having a viscosity of 5 cP or less and a vapor pressure of 1 mmHg or more at a temperature of 20 ° C. under atmospheric pressure. It is characterized by being (claim 1).

Et al is, the in drying step, have a penetration treatment to infiltrate the solvent which is contained in the ground processing material to the printing paper, and volatile process for the solvent to volatilize into the atmosphere, the two processing steps of (Claim 2 ).

Wherein in the drying process step, it is preferable to dry the ground processing material by the heating device (claim 9).
Further, in the ground processing material supplying step, it is preferable to supply is transferred to the printing surface in the printing method of the ground processing material (claim 10).
In this case, in the ground processing material supplying step, it is preferable to be printed on the printing surface of the ground processing material in a predetermined dot shape (claim 11). That is, the base treatment agent may be supplied to the printing surface by solid printing, but it is preferable to supply the surface treatment agent to the printing surface by an appropriate halftone dot shape instead of solid printing.

Further, in the ground processing material supplying step, it is preferred to supply the ground processing material to a portion of the printing surface to include a print location photos or advertisement segment in said printing surface (claim 12).
The offset printing machine of the present invention is a printing machine that performs offset printing on a printing paper, and supplies a ground treatment agent to the printing surface of the printing paper upstream of the first color blanket cylinder nip portion of the printing apparatus. The substrate processing apparatus includes a substrate processing agent supply unit that includes a substrate processing agent supply unit, and the substrate processing agent supply device includes a drying process that performs a drying process on the substrate processing agent supplied to the printing surface downstream of the substrate processing agent supply unit. It is characterized in that a section is provided (claim 13 ).

  The offset printing press according to the present invention can be applied to, for example, a commercial offset rotary press (quotient off) and a newspaper rotary press, and these rotary presses mainly perform printing at a nip between two blanket cylinders. Some print at the nip between the blanket cylinder and impression cylinder. The above-mentioned blanket cylinder nip portion includes these blanket cylinder-blanket cylinder nip and blanket cylinder-impression cylinder nip.

Also in this offset printing machine, the surface treatment agent is a liquid material having a viscosity of 0.01 to 50 P at a temperature of 20 ° C. under atmospheric pressure (in addition to a liquid, a slurry such as a slurry in which a solid material is mixed) solid substance is also included), and, a vapor pressure 1mmHg more solvents Ru are contained in the following viscosity 5cP at a temperature condition of 20 ° C. under atmospheric pressure (claim 13).
Moreover, it is preferable that the said drying process part performs the said drying process by the osmosis | permeation process which permeate | transmits the solvent contained in the said surface treating agent to the said printing paper, and the volatilization process which volatilizes the said solvent to air | atmosphere. (Claim 14 ).

Wherein the drying section is preferably a heating device is provided for heating and drying the ground processing material (claim 21).
The printing paper is low-whiteness printing paper, and the offset printing machine is configured as a rotary press. The ground treatment agent supply device is configured to feed a blanket cylinder nip of the first color of the printing device from a paper feeding unit. It is preferable that the first color blanket cylinder nip portion is disposed downstream of the first color blanket cylinder nip portion and upstream of the first color blanket cylinder nip portion. 22 ).

The apparatus for changing the web path length is, for example, a floating roller that absorbs fluctuations in paper feed tension, a dancer roller that controls the tension at the entrance of the printing unit, and the like.
In addition, it is preferable that the base treatment agent supply device transfers the base treatment agent to the printing surface by a printing method and supplies it (claim 23 ).

In this case, the ground processing material supplying apparatus, the ground processing material that is preferably printed on the printing surface at a predetermined dot percent or more high dot percent (claim 24).
In addition, it is preferable that the base treatment agent supply device supplies the base treatment agent to a part of the printing surface so as to include a printed portion of a photograph or an advertisement part on the printing surface.

In the printing method and offset printing machine using the offset printing machine, the printing paper is low whiteness printing paper (specifically, newsprint paper), and the offset printing machine is a newspaper rotary press. (Claims 3 and 15 ).
Further, the surface treatment agent is preferably a whiteness improver (claims 4 and 16 ).
In this case, the whiteness improver is preferably a white ink (claims 5 and 17 ).

Alternatively, the base treatment agent is preferably a special color ink having a basic ink color of cyan, magenta or yellow and an ink color other than white or black ink color (claims 6 and 18 ).
The surface treatment agent may be aqueous (Claims 7 and 19 ) or oily (Claims 8 and 20 ).

According to the printing method (Claim 1) and the offset printing machine (Claim 13 ) using the offset printer of the present invention, the ground treatment agent is supplied to the printing surface of the printing paper, and the ground treatment agent on the printing surface is dried. Since the offset printing is performed on the printing paper, the ink transferred after the base treatment is mixed with the base treatment agent to prevent the ink from becoming turbid. Prints well.

In particular , the surface treatment agent is transferred to the printing surface of the printing paper via a roller, for example, by making it a liquid having a viscosity of about 0.01 to 50 P at a temperature of 20 ° C. under atmospheric pressure. in the case of supply, Ru can be properly supplied. That is, when the viscosity of the surface treatment agent is higher than about 50P, the surface treatment agent is too hard to transfer the ink through the roller. If it is lower than about 01P, the conveying performance of the surface treatment agent by the roller may be lowered, and it may be difficult to supply.

Further, by adding a solvent having a viscosity of about 5 cP or less and a vapor pressure of 1 mmHg or more at a temperature of 20 ° C. under atmospheric pressure before the printing ink is transferred to the printing surface of the printing paper, that of the ground processing material more easily dried.
In addition, drying of the base treatment agent can be achieved quickly by performing a drying treatment by a permeation treatment that permeates the printing paper with the solvent contained in the base treatment agent and a volatilization treatment that volatilizes the solvent into the atmosphere. (Claims 2 and 14 ).

In addition, when the offset press is a newspaper rotary press that uses newsprint paper, which is low-whiteness printing paper as the printing paper, the target color tone is used for, for example, full-color photographs and demanding advertisements relating to color tone due to the paper quality. Although it may be difficult to print, it is possible to print to a target color tone that has been difficult by performing the base treatment while preventing the ink from becoming cloudy (claims 3 and 15 ). .

By using a whiteness improver such as white ink as a base treatment agent, the whiteness of low-whiteness printing paper can be improved, and even when the color tone requirement is severe, it is possible to print to the target color tone (Claims 4, 5, 16, and 17 ).
In addition, by using special color inks other than the basic ink colors of cyan, magenta, yellow and white and black as the base treatment agent, it is possible to express advertisements in impressive colors, for example. (Claims 6 and 18 ).

Further, by actively drying the surface treatment agent with a heating device, the surface treatment agent can be dried more quickly, and is particularly suitable for printing at a high speed (claims 9 and 21 ).
Further, when applied to a rotary press using low whiteness printing paper as the printing paper, the ground treatment agent supply device changes the web path length from the paper feeding unit to the blanket cylinder nip portion of the first color of the printing device. By disposing downstream of the apparatus and upstream of the blanket cylinder nip portion of the first color, the ground treatment agent can be supplied in correspondence with the phase of the printing paper in the downstream printing apparatus, for example, it becomes easy to perform the background processing only a predetermined portion of the printing paper (claim 22).

In addition, by transferring the ground treatment agent to the printing surface by a printing method and supplying it, the ground treatment becomes easy, and the ground treatment can be easily performed only on a predetermined portion of the printing paper (claim). Item 10, 23 ).
In this case, if the surface treatment agent is printed on the printing surface in a predetermined halftone dot shape, the surface treatment agent can be supplied to an appropriate concentration (claims 11 and 24 ).

If the ground treatment agent is supplied to a part of the printing surface so as to include the printed portion of the photograph or the advertisement part on the printing surface, the ground treatment can be efficiently performed and the processing cost can be suppressed. In addition, on the paper where the article and the photograph or the advertisement are mixed, the article portion may be easier to read if the background processing is not performed, and such a case can be easily dealt with (claims 12 and 25 ). ).

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
First, the first embodiment of the present invention will be described. FIGS. 1 to 6 illustrate the first embodiment of the present invention. FIG. 1 is an explanatory diagram showing the main configuration of the offset printing machine, and FIG. FIG. 3 is a conceptual diagram relating to drying of the surface treatment agent, FIG. 3 is a diagram showing the relationship between the viscosity of the solvent contained in the surface treatment agent and the permeation rate into paper, and FIG. 4 is a diagram of the solvent contained in the surface treatment agent. FIG. 5 is a front view showing the printing surface of the newspaper, and FIG. 6 is a flowchart for explaining a printing method by the offset printing machine.

The present embodiment relates to a newspaper rotary press as an offset printing press. As shown in FIG. 1, a web-like (continuous paper) newspaper to be printed on the upstream side of a printing unit (printing apparatus) 6 of the newspaper rotary press. A base treatment agent supply device 4 for supplying a base treatment agent to the printing surface of a sheet (hereinafter also referred to as a web) 10 is added. Here, since an example in which white ink is used as the ground treatment agent will be described, the ground treatment agent supply device is also referred to as a white ink supply device 4. The newsprint (web) 10 has a general whiteness of, for example, 54 to 55% and a basis weight of 42 to 44 g / m ^2, but is not limited thereto.

That is, in the newspaper rotary press, the web 10 equipped as the web 1a in the paper feeding unit 1 is unwound from the infeed unit 2 and conveyed to the printing unit 6, and is required by a printing unit (not shown) provided in the printing unit 6. After the color ink is transferred, it is output as a signature after passing through a cooling section, a web path section, and a folding machine (all not shown).
The infeed unit 2 is disposed to face the infeed roller 2a, the dancer roller 2b that adjusts the tension of the web 10 while moving and changing the web path distance, and the infeed roller 2a and the web 10 sandwiched therebetween. It comprises a guide roller 3a and a guide roller 3b arranged on the exit side of the web 10 from the dancer roller 2b, and feeds it toward the printing unit 7 while holding the web 10 in a set state. ing.

Note that the printing unit 6 is provided with a single printing unit in the case of monochromatic printing, but here is provided with a plurality of printing units so as to perform multicolor printing such as full color.
In such an existing newspaper press, downstream of the dancer roller 2b, which is a device for changing the web path length of the infeed unit 2, upstream of the first color blanket cylinder nip (not shown) of the printing apparatus. In this case, a base agent supply device 4 is added to the upstream of the guide roller 3c portion at the entrance of the printing unit 6.

In the present embodiment, a white ink supply device 4 as a base treatment agent supply device is added to an existing printing machine, and a guide roller shown in FIG. 1 is used as a configuration for more effectively using the existing printing machine. It is also conceivable to use 3b instead of the impression cylinder of the substrate treatment agent supply apparatus.
The base treatment agent supply device (white ink supply device) 4 includes a base treatment agent processing unit (white ink supply unit) 4A and a drying processing unit 4B.

  The surface treatment agent supply unit 4A is configured in the same manner as a general offset printing unit, and corresponds to the surface treatment agent supply rolls 4a and 4c for supplying the surface treatment agent to the printing plate and the printing region of the surface treatment agent. Plate cylinders 4b and 4d on which plates are mounted are provided. If necessary, a plate cylinder is provided at the position of the surface treatment agent supply rolls 4a and 4c, and the surface treatment agent received from the surface treatment agent supply rolls 4a and 4c is transferred to the surface (printing surface) of the web 10. A transfer cylinder may be provided at the positions of the plate cylinders 4b and 4d. In this case, the transfer cylinder may correspond to, for example, a commercial offset rotary press (quotient off) or a blanket cylinder of a newspaper rotary press.

  Here, since the surface treatment agent is transferred to both surfaces of the web 10, a first surface treatment agent supply system having a surface treatment agent supply roll 4a and a plate cylinder 4b is provided on one surface side of the web 10, A second surface treatment agent supply system having a surface treatment agent supply roll 4c and a plate cylinder 4d is provided on the other surface side of the web 10, but if the surface treatment agent is transferred only to one side of the web 10, The unnecessary side surface treatment agent supply system may be set not to be used, or the unnecessary side surface treatment agent supply system may not be provided from the beginning.

In addition, the drying processing unit 4B provided downstream in the base processing agent supply apparatus 4 is for drying the base processing agent transferred to the printing surface of the web 10, and in the present embodiment, the drying processing unit 4B A heating device 5 for heating and drying the agent is provided.
In addition, as the heating apparatus 5, the hot air system which dries by blowing warm air on the printing surface of the web 10, the vapor | steam system which dries by spraying high temperature steam on the printing surface of the web 10, and the method of irradiating infrared rays Or a combination of these (all are non-contact systems), or a high temperature roll system in which a high temperature roll is brought into contact with the printing surface of the web 10 and rotated at a peripheral speed synchronized with the web 10 speed. Things can be applied.

Here, any of the warm air method, the steam method, the infrared irradiation method, and the high temperature roll method can be dried by heating from the back side of the printing surface, not from the printing surface. Furthermore, when the surface treatment agent is an energy beam curable type using an electron beam or ultraviolet ray, a drying apparatus using an electron beam or ultraviolet ray irradiation can be used.
In particular, it is preferable to use high-temperature steam as appropriate, because problems such as web shrinkage due to a decrease in moisture accompanying heating of the web 10 are prevented. For example, it is possible to use a contact method in which a high temperature roller is brought into contact with the web, a separate high temperature roller can be provided, or the guide roller 3C can be heated and dried by contact. Here, a non-contact type in which warm air and high temperature steam are mixed is used.

  For example, a surface treatment agent such as white ink has a viscosity of 0.01 to 50 P in a reference state (temperature state at 20 ° C. under atmospheric pressure), particularly for supplying a surface treatment agent using a roller. Appropriate viscosity. That is, when the viscosity is higher than about 50 P, the base treatment agent is too hard and it is difficult to transfer the ink through the roller. On the other hand, it is preferable that the lower limit of the viscosity of the surface treatment agent is, for example, about a viscosity equivalent to 0.01 P in order to prevent the supply performance of the surface treatment agent from being deteriorated by the roller.

Next, the solvent characteristics in the surface treatment agent that affect the drying characteristics of the surface treatment agent will be described.
In the drying process, the solvent contained in the base treatment agent is dried from two processes, a process for penetrating the printing paper (penetration process) and a process for volatilizing in the atmosphere (volatilization process).
FIG. 2 is a conceptual diagram illustrating the drying process of the base treatment agent. As shown in the drawing, the base treatment agent 20 contains at least a pigment 21, a binder resin 22, and a solvent 23 as a colorant. As shown in FIG. 2 (a), the base treatment layer formed by the base treatment agent 20 immediately after being applied to the printing paper 10 contains all of the pigment 21, the binder resin 22, and the solvent 23. However, as the drying process proceeds, as shown in FIG. 2 (b), the solvent 23 is removed.

In this drying step, the substrate treatment agent is dried while the penetration of the solvent into the printing paper and the diffusion into the atmosphere due to the volatilization of the solvent proceed simultaneously. At this time, as a matter of course, drying of the base treatment agent is achieved more rapidly as the solvent penetrates into the printing paper more rapidly and as the solvent volatilizes more quickly.
In order to supply the ground treatment agent to the printing surface of the printing paper on the printing machine and subsequently print images and characters with the printing ink transferred by the printing unit 6, the drying rate of the ground treatment agent is not sufficiently high. In order to increase the drying speed, a solvent for the base treatment agent is selected, but as a criterion for selection, the viscosity and evaporation rate of the solvent at room temperature are points.

In the case where there is no significant difference in the wettability between the solvent and the printing paper, that is, in the case of normal paper that is not subjected to water repellent treatment, as shown in FIG. 3, the lower the solvent viscosity is, the lower the solvent penetration rate is. Tend to be fast.
FIG. 3 shows the permeation rate of the solvent into the paper (unit area per second) measured with a Bristow type liquid dynamic absorption tester of Kumagai Riki Kogyo Co., Ltd. for alcohol solvents having different viscosities. ² is a graph showing the amount of solvent permeation into paper, ml / m ² · sec). More specifically, a 25 mm wide x 1000 mm long newspaper is wrapped around a sample disk having a width of 25 mm x a diameter of 318.5 mmφ, and a head box having a width of 15 mm and a slit width of 1 mm is filled with 40 μl of solvent. It is the result measured in the range of contact pressure 0.1MPa and newspaper rotation speed 1.25-250mm / sec with newspaper.

To reduce the burden on the heating device for drying the surface treatment agent, for example, to complete the drying of the surface treatment agent at room temperature and in a short time (short mileage section of printing paper) without using a heating device The permeation rate into the paper is at least 5 ml / m ² · sec or more, preferably 10 ml / m ² · sec or more, and the solvent viscosity at that time is 5 cP or less, preferably 3 cP or less, more preferably 1 cP or less, respectively. It can be found from FIG.

Furthermore, as shown in FIG. 4, the lower the viscosity, the higher the vapor pressure at room temperature, and the higher the evaporation rate at room temperature.
In addition, FIG. 4 classifies the solvent considered to be usable for the surface treatment agent of the present invention into an aliphatic hydrocarbon solvent, a chlorinated hydrocarbon solvent, an alcohol solvent, an ether solvent, a ketone solvent, and water, It is a graph which shows the result of having investigated the relationship between the viscosity of a solvent in a room temperature (20 degreeC) under atmospheric pressure, and vapor pressure.

To reduce the burden on the heating device for drying the surface treatment agent, for example, to complete the drying of the surface treatment agent at room temperature and in a short time (short mileage section of printing paper) without using a heating device It can be seen from FIG. 4 that the vapor pressure of the solvent is preferably at least 1 mmHg or more, preferably 10 mmHg or more, more preferably 50 mmHg or more.
Therefore, in order to “dry the ground treatment agent such as white ink before the printing paper (web) is transferred with the printing ink by the printing unit 6”, which is the subject of the present invention, the ground treatment agent of the present invention is used. The solvent used is a solvent having a viscosity of 5 cP or less and a vapor pressure of 1 mmHg or more, preferably a viscosity of 3 cP or less and a vapor pressure of 10 mmHg or more, more preferably a viscosity of 1 cP or less and a vapor pressure of 50 mmHg or more in a temperature state of 20 ° C. under atmospheric pressure. It is. Of course, the combination of the optimum regions of the viscosity and the vapor pressure is not limited to this, and the viscosity may be further limited, or the vapor pressure may be further limited.

  However, the dry state as used in the present invention means that at least the paper surface treatment agent is mixed with the printing ink transferred by the printing unit 6 and does not cause turbidity in the printing ink. It is not necessary for all the solvent in the agent to migrate from the base treatment layer on the paper surface to the printing paper or to the atmosphere. Therefore, the solvent for increasing the drying property may be contained in an amount of 1 to 30% by weight in the base treatment agent. If it is less than 1%, the effect of improving the drying property is not exhibited. On the other hand, if it is 30% or more, there is a high possibility that a problem that drying, particularly evaporation, is too early and handling of the ground treatment agent on the printing press becomes difficult will occur.

Also, in order to impart other properties required for the surface treatment agent such as transferability, image quality, maintainability, storage stability, and safety, if necessary, in addition to a solvent for increasing the drying property, atmospheric pressure Needless to say, an appropriate amount of a solvent having a viscosity of 5 cP or more and a vapor pressure of 1 mmHg or less at 20 ° C. may be included.
The supply of the ground treatment agent onto the web 10 by the ground treatment agent supply device 4 is performed at a required location on the printing surfaces (printed pages) 11a and 11b as shown in the printed and cut newspaper 11 in FIG. Here, it is performed only for the photo print location 13 and the advertisement print locations 14 and 15. An example of the base treatment agent supplied to the newspaper 11 is white ink. White ink is not supplied to the portion 12 where the article is printed. That is, such a process can be performed by preparing a printing plate for white ink corresponding to the required locations 13, 14, 15 and mounting it on the plate cylinders 4b, 4d for printing.

In the printing plate for white ink, basic ink, or special color ink, the printing portion may be solid (halftone dot area ratio 100%), or may be an appropriate halftone dot shape that is not solid printing. In this case, drying of each ink can be stopped while realizing the whiteness of the printed surface of the web 10 or the optical density of the ink to some extent.
Further, as described above, the white ink supply device 4 is downstream of the dancer roller 2b, which is a device for changing the web path length of the infeed unit 2, and upstream of the first color blanket cylinder nip portion of the printing device. Since it is provided, it is easy to match the printing plate for white ink with the phase of each printing plate in the printing unit 6, and printing of the white ink on the required portions 13, 14, 15 as described above can be performed reliably. It has become.

Since the newspaper rotary press as an offset printing press according to the first embodiment of the present invention is configured as described above, printing is performed on the surface (printing surface) of the web 10 as shown in the flowchart of FIG. It is.
That is, first, white ink (a ground treatment agent) is applied to the printing surface of the web 10 fed from the paper feeding unit 1 while the tension state is adjusted by the infeed unit 2 by the white ink supply unit 4A of the white ink supply device 4. Is supplied (step S10; substrate treatment agent supply step). The supply of the white ink is performed only in the required locations 13, 14, 15 (FIG. 5) by the printing method.

Next, the web 10 proceeds to the drying processing unit 4B, and the white ink (base treatment agent) on the printing surface is heated and dried by the heating device 5 (step S20; drying step). Then, printing is performed in the printing unit 6 (step S30; printing step).
As described above, the white ink on the printing surface is dried, and when printing is started in the printing unit 6, the printing ink transferred by the printing unit 6 is mixed with the printing ink to cause turbidity in the printing ink. Since there is no state, printing is performed without causing turbidity in the printing ink.

  As a result, the surface of the newspaper (web) 10 having a low whiteness is processed to a high whiteness with the white ink, and a full-color photograph (printed portion 13 in FIG. 5) or an advertisement (printed portion 14 in FIG. 5). 15) is printed without causing turbidity or the like in the printing ink, and it becomes possible to realize printing of a color tone desired to be reproduced using a high whiteness background. In the case of a photograph, it is possible to print the original image faithfully, and in the case of an advertisement, for example, it is possible to print the original image faithfully, and to realize printing that is more vivid and has a higher advertising effect.

  In particular, since white ink is supplied only to the photographic part and the advertisement part on the printed surface, that is, to a part of the printed surface, the ground treatment can be efficiently performed and the processing cost can be suppressed. Further, the article portion 12 is rather easy to read by not performing the background processing.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 7 is an explanatory diagram showing a main configuration of an offset printing machine according to the second embodiment of the present invention. In FIG. 7, the same reference numerals as those in FIG.

  In the first embodiment, the surface treatment agent supply device (the surface treatment agent supply unit 4A and the drying treatment unit 4B) 4 is added to an existing newspaper rotary press. It is assumed that 4 has been incorporated into a newspaper press from the beginning. That is, as shown in FIG. 7, the substrate processing agent supply device 4 is provided alongside the upstream of the printing unit 6 including the printing units 6 a and 6 b and the like. Other than this, the configuration is the same as in the first embodiment. In the present embodiment, a case where white ink is used as the base treatment agent will be described as an example.

  In the case of this embodiment as well, as in the first embodiment, the white ink supply device 4 is downstream of the dancer roller 2b that is a device that changes the web path length of the infeed unit 2 (however, here, Since the web 10 is provided downstream of the guide roller 3c for guiding the web 10 to the printing apparatus 6 and upstream of the blanket cylinder nip 6c of the printing unit 6a for the first color of the printing apparatus 6, the printing plate for white ink is printed on the printing unit. 6 is easy to match with the phase of each printing plate, so that the white ink can be surely printed on the required portions 13, 14, and 15 described in the first embodiment.

  Even with such a configuration, like the first embodiment, the printing ink is printed with the printing ink without causing turbidity due to the white ink, and it is desired to reproduce it using a high whiteness background. The effect that it becomes possible to realize color tone printing is obtained.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. FIG. 8 is an explanatory diagram showing a main configuration of an offset printing machine according to the third embodiment of the present invention. 8, the same reference numerals as those in FIG. 1 denote the same components, and a part of these descriptions is omitted. Also in this embodiment, a case where white ink is used as the base treatment agent will be described as an example.

In the present embodiment, the ground treatment agent supply device 4 itself is the same as in the first and second embodiments, but the upstream portion of the printing press from the ground treatment agent supply device 4 is different from the first and second embodiments. ing.
That is, in the first and second embodiments, a dancer roller is provided as a device for changing the web path length. However, in this embodiment, as shown in FIG. 8, there is no dancer roller and the device for changing the web path length. A floating roller 7 is provided.

  The floating roller 7 is a device that absorbs fluctuations in the paper feed tension. When the paper feed tension decreases during acceleration / deceleration of the rotary press, during a paster, or during an emergency stop, the left side in FIG. Move in the direction of the chain line) and absorb the decrease in tension. On the other hand, when the sheet feeding tension increases, the sheet moves in the direction of the right side (see the two-dot chain line) in FIG.

  Note that the dancer roller 2b and the infeed roller 2a (see FIGS. 1 and 7) described in the first and second embodiments positively detect the tension at the entrance of the printing unit to detect the position of the dancer roller 2b and the infeed roller. This is a device for changing the peripheral speed of 2a to suppress the tension fluctuation and to stabilize the tension at the entrance of the printing unit, and has a drive device for driving the dancer roller 2b, but this floating roller 7 is not provided with a drive device in particular. (Simple pendulum roller) is simply a device for absorbing tension fluctuations. However, it is the same as the dancer roller 2b and the infeed roller 2a in that the web path length is changed.

Accordingly, when a background process such as supplying white ink is performed on a required portion of the web 10, the white ink supply is performed in order to prevent a phase shift of the print position caused by a change in the web path length. The apparatus (ground treatment agent supply apparatus) 4 is arranged downstream of the floating roller 7 which is an apparatus for changing the web path length.
Even with such a configuration, as in the first and second embodiments, printing ink can be printed without causing turbidity due to white ink, and the color tone to be reproduced using a high whiteness background. The effect that printing can be realized is obtained.

  In addition, when there are a plurality of “devices for changing the web path length”, the “device for changing the web path length” located further downstream from the paper feed unit to the nip portion of the blanket cylinder of the first color. It is preferable to arrange a white ink supply device (base treatment agent supply device) 4 on the downstream side.

[Others]
Although the embodiment of the present invention has been described above, the present invention is not limited to such a configuration, and can be implemented by appropriately changing the configuration without departing from the spirit of the present invention. is there.

For example, in the above embodiment, a newspaper rotary press has been described as an example, but the present invention is not limited to a newspaper rotary press and can be widely applied to offset printing presses.
Moreover, although white ink is used as a base treatment agent, when improving whiteness, whiteness improvement agents other than white ink, such as a decoloring agent, may be used, for example. When a decoloring agent is used, it is difficult to carry out the washing process on a printing press. Therefore, the decoloring agent is required to be a chemical that sublimes (or evaporates) itself with the colored components of newspaper.

  Further, the printing paper to be subjected to the background processing is not limited to low whiteness printing paper such as newsprint. Of course, the surface treatment agent is not limited to the whiteness improving agent, for example, a material that improves the smoothness of the paper surface, such as a transparent ink (for example, varnish), for example, an ink containing a metal component, a reflection A thing which improves the brightness (different from whiteness), such as a rate improver, can also be applied.

  It is also conceivable to use spot color inks other than white, that is, basic ink colors of cyan, magenta and yellow, and spot color inks of ink colors other than white and black ink colors as the surface treatment agent. The application of such special color inks to the background greatly increases the variation of color expression and enables highly impressive color development. .

Further, a plurality of base treatment agents may be used. That is, a plurality of ground treatment agent supply devices such as the white ink supply device 4 are provided to perform different ground treatments. According to this, for example, different ground treatments such as whiteness improvement, lightness improvement of other colors and surface smoothing can be performed on the same paper surface, and various demands for printing can be met. .
In the above-described embodiment, white ink (a ground treatment agent) is supplied to the entire area for the photograph part and the advertisement part on the printing surface, but the white color is applied only to the necessary part in the photograph part and the advertisement part. Ink (base treatment agent) may be partially supplied. In other words, the base processing is not performed on the region where the base is hardly present. As a result, the substrate processing can be performed more efficiently, and the processing cost can be further suppressed. In this case as well, it is preferable that the outline of the background processing is made larger and the background processing is also performed on the boundary portion of the region where there is almost no background by ink so that the portion not subjected to the background processing is not exposed.

  In the above embodiment, the heating unit 5 is provided in the drying processing unit 4B. However, as described above, the base treatment agent such as white ink is fast-drying and can be dried at room temperature in a short time. If there is, as a specific example of the drying processing unit 4B, the drying processing unit 4B may be a simple space without the heating device 5, that is, a natural drying (or room temperature drying) section.

It is explanatory drawing which shows the principal part structure of the offset printing press concerning 1st Embodiment of this invention. It is a conceptual diagram regarding the drying of the surface treatment agent concerning each embodiment of this invention, (a) shows the state before drying of a surface treatment agent, (b) shows the state after drying progress of a surface treatment agent. It is a figure which shows the relationship between the viscosity of the solvent contained in the base-treatment agent concerning each embodiment of this invention, and the penetration | infiltration rate to paper. It is a figure which shows the relationship between the viscosity and vapor pressure of the solvent containing the base-treatment agent concerning each embodiment of this invention. It is a front view which shows the printing surface of the newsprint concerning 1st Embodiment of this invention. It is a flowchart explaining the printing method by the offset printing machine concerning 1st Embodiment of this invention. It is explanatory drawing which shows the principal part structure of the offset printing press concerning 2nd Embodiment of this invention. It is explanatory drawing which shows the principal part structure of the offset printing machine concerning 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Paper feed part 1a Winding paper 2 Infeed part 2a Infeed roller 2b Dancer roller 3a, 3b, 3c Guide roller 4 Ground treatment agent supply apparatus 4A Ground treatment agent processing part 4B Drying treatment part 4a, 4c Ground treatment agent supply roll 4b, 4d Plate cylinder 5 Heating device 6 Printing section (printing device)
7 Floating roller 10 Newspaper (web) as printing paper
11a, 11b Print surface (print page)
12 Location for printing articles 13 Location for printing photos 14,15 Location for printing advertisements

Claims (25)

A printing method using an offset printing machine,
A surface treatment agent supply step for supplying a surface treatment agent to the printing surface of the printing paper;
A drying step of drying the surface treatment agent supplied to the printing surface by the surface treatment agent supply step;
A printing step for performing the offset printing on the printing paper dried by the drying step ;
The surface treatment agent is a liquid having a viscosity of 0.01 to 50 P at a temperature of 20 ° C. under atmospheric pressure, and having a viscosity of 5 cP or less and a vapor pressure of 1 mmHg or more at a temperature of 20 ° C. under atmospheric pressure. The printing method by an offset printing machine characterized by including . The drying step includes two treatment steps: a permeation treatment for permeating the solvent contained in the ground treatment agent into the printing paper, and a volatilization treatment for volatilizing the solvent into the atmosphere. A printing method using an offset printer according to claim 1 . The printing paper is a low whiteness printing paper,
The offset printing press characterized in that it is a newspaper rotary press, the printing method according to claim 1 or 2, wherein the offset printing press. The ground processing material is characterized by a whiteness enhancer, a printing method according to an offset printing machine according to any one of claims 1-3. The printing method using an offset printer according to claim 4 , wherein the whiteness enhancer is white ink. The surface treatment agent is, cyan, magenta, and characterized in that the basic ink color and white, features ink in the ink color other than ink color black yellow, according to any of claims 1 to 3 Printing method using an offset printer. The ground processing material is characterized in that it is aqueous, printing method according to an offset printing machine according to any one of claims 1-6. The printing method by an offset printing machine according to any one of claims 1 to 6 , wherein the surface treatment agent is oily. The printing method using an offset printing machine according to any one of claims 1 to 8 , wherein, in the drying treatment step, the ground treatment agent is dried by a heating device. The printing method by an offset printing machine according to any one of claims 1 to 9 , wherein in the base treatment agent supply step, the base treatment agent is transferred to the printing surface by a printing method and supplied. . 11. The printing method using an offset printing machine according to claim 10 , wherein in the surface treatment agent supply step, the surface treatment agent is printed on the printing surface in a predetermined halftone dot shape. And in the ground processing material supplying step, characterized in that said supplying ground processing material to a portion of the printing surface to include a print location photos or advertisement segment in said printing surface, any claim 1 to 11 A printing method using the offset printing machine according to claim 1. A printing machine that performs offset printing on printing paper,
Provided with a base treatment agent supply device provided with a base treatment agent supply section for supplying a base treatment agent to the printing surface of the printing paper on the upstream side of the first color blanket cylinder nip portion of the printing apparatus;
The ground treatment agent supply apparatus includes a drying processing unit for drying the ground treatment agent supplied to the printing surface downstream of the ground treatment agent supply unit ,
The surface treatment agent is a liquid having a viscosity of 0.01 to 50 P at a temperature of 20 ° C. under atmospheric pressure, and having a viscosity of 5 cP or less and a vapor pressure of 1 mmHg or more at a temperature of 20 ° C. under atmospheric pressure. wherein the but has been contained, offset press. The drying processing unit performs the drying process by a permeation process for permeating the solvent contained in the base treatment agent into the printing paper and a volatilization process for volatilizing the solvent into the atmosphere. The offset printing machine according to claim 13 . The printing paper is a low whiteness printing paper,
The offset printing press according to claim 13 or 14 , wherein the offset printing press is configured as a newspaper rotary press. The offset printing machine according to claim 13 , wherein the surface treatment agent is a whiteness improver. The offset printing machine according to claim 16 , wherein the whiteness enhancer is white ink. 16. The surface treatment agent according to any one of claims 13 to 15 , wherein the base treatment agent is a special color ink other than cyan, magenta, and yellow basic ink colors and white and black ink colors. Offset printing machine. The offset printing machine according to any one of claims 13 to 18 , wherein the surface treatment agent is aqueous. The offset printing machine according to any one of claims 13 to 18 , wherein the surface treatment agent is oily. The offset printing machine according to any one of claims 13 to 20, wherein the drying processing unit includes a heating device that heats and drys the base treatment agent. The printing paper is a low whiteness printing paper, configured as a rotary press,
The surface treatment agent supply device is downstream of a device that changes a web path length from the paper feeding unit to the blanket cylinder nip portion of the first color of the printing apparatus to the blanket cylinder nip portion of the first color. 14. The offset printing machine according to claim 13 , wherein the offset printing machine is disposed upstream of the first color blanket cylinder nip portion. The offset printing machine according to any one of claims 13 to 22 , wherein the substrate treatment agent supply device transfers the substrate treatment agent to the printing surface by a printing method and supplies the substrate . The offset printing machine according to claim 23 , wherein the substrate treatment agent supply device prints the substrate treatment agent on the printing surface with a high dot area ratio equal to or higher than a predetermined dot area ratio. The ground processing material supplying apparatus, characterized in that said supplying ground processing material to a portion of the printing surface to include a print location photos or advertisement segment in said printing surface, any claim 13 to 24 An offset printing machine according to claim 1.

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