(19)
(11)EP 2 927 010 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
21.03.2018 Bulletin 2018/12

(21)Application number: 13830076.9

(22)Date of filing:  22.07.2013
(51)Int. Cl.: 
B41M 1/08  (2006.01)
B41F 23/04  (2006.01)
B41M 7/00  (2006.01)
B41F 7/02  (2006.01)
B41M 1/30  (2006.01)
(86)International application number:
PCT/JP2013/004440
(87)International publication number:
WO 2014/083722 (05.06.2014 Gazette  2014/23)

(54)

PRINTING METHOD USING OFFSET PRINTER

DRUCKVERFAHREN MIT EINEM OFFSETDRUCKER

PROCÉDÉ D'IMPRESSION UTILISANT UNE IMPRIMANTE OFFSET


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 28.11.2012 JP 2012260075

(43)Date of publication of application:
07.10.2015 Bulletin 2015/41

(73)Proprietor: Yamato Grand Co., Ltd.
Aichi 451-0025 (JP)

(72)Inventor:
  • KAWAI, Shingo
    Nagoya-shi Aichi 451-0025 (JP)

(74)Representative: Goddar, Heinz J. 
Boehmert & Boehmert Anwaltspartnerschaft mbB Pettenkoferstrasse 22
80336 München
80336 München (DE)


(56)References cited: : 
EP-A1- 0 697 290
JP-A- H0 929 937
JP-A- H1 199 625
JP-A- H08 501 589
JP-A- H09 269 566
JP-A- 2001 162 919
JP-A- 2004 106 186
JP-A- 2008 080 591
JP-A- 2010 000 742
US-A- 5 295 437
JP-A- H0 239 940
JP-A- H1 158 923
JP-A- H08 324 141
JP-A- H09 104 104
JP-A- S63 252 777
JP-A- 2001 225 441
JP-A- 2007 296 830
JP-A- 2008 291 167
US-A- 3 986 874
  
  • MITSUGU HOSHIKAWA: 'Shiki eno Mizunashi UV Insatsu' JAPAN PRINTER, INSATSU GAKKAI SHUPPANBU 15 November 2003, page 12, XP008173275
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

Technical Field



[0001] The present invention relates to a printing method using an offset printing press, and in particular to a printing method using an offset printing press having excellent image formability.

Background Art



[0002] Offset printing is known as a printing technique.

[0003] Such an offset printing adopts a system of transferring ink applied to a plate to an intermediate transferring member, such as a blanket, and then printing a substrate, such as paper.

[0004] Conventionally, in the field of offset printing, from the viewpoints of shortening delivery time and reducing costs, methods of operating an offset printing press at a high speed have been suggested.

[0005] For example, an offset printing press is known that performs printing using quick-drying ink that is cured by irradiating a printing surface of a running printing substrate with ultraviolet rays, via a printing plate mounted on an outer periphery of a plate cylinder and a blanket mounted on an outer periphery of a blanket cylinder (for example, see Patent Literature 1).

[0006] In the offset printing press, using quick-drying ink makes high-speed printing possible.

[0007] On the other hand, a back-printed article obtained by providing a print layer onto a substrate having transparency by offset printing and coating the printed layer with white ink by means of a coater is disclosed (for example, see Patent Literature 2).

[0008] In such a printed matter, offset printing is performed using UV curable ink on a polypropylene sheet treated by corona discharge, where UV curing is performed at a printing speed of 6500 sheets per hour (approximately 30 m/min).

[0009] By the way, in the offset printing, printing is generally performed on a wet plate using water.

[0010] In printing on a wet plate, control of the heaped amount of ink, pattern edges, or the like can be performed not only by ink supply but also by the amount of dampening water to the plate.

[0011] However, there is the disadvantage that image quality is unstable because the amount of dampening water depends on a humidity or a temperature in the air, or the like.

[0012] There is also the disadvantage that emulsification proceeds on the border between water and ink and quality is impaired if the emulsified part remains. In this case, it also becomes difficult to perform post-process on a film or a plate after the offset printing separately or to perform resin application after the post-process.

[0013] On the other hand, in recent years, in the offset printing, a waterless plate having a structure in which a pattern is lipophilic and a silicon layer is formed on a non-image area (an area which is not printed) has been developed.

[0014] In printing using a waterless plate, since water is not used, such a problem as a variation in image quality due to the amount of dampening water or emulsification caused due to water and ink are solved.

Citation List


Patent Literature



[0015] 

PTL 1: Japanese Patent Application Laid-Open No. 2009-274432

PTL 2: Japanese Patent Application Laid-Open No. 2007-29830

In addition, as printing method using an offset printing press of the related art, a printing method described in US5295437 is known.

Summary of Invention


Technical Problem



[0016] In printing using a waterless plate, however, the formability of an image is not sufficient. That is, the transferability of ink from a waterless plate to a blanket and the transferability of ink from a blanket to a substrate are not sufficient.

[0017] Incidentally, ink and a substrate suitable for offset printing using a waterless plate that solves such a problem have not been developed yet.

[0018] The present invention has been made in view of the above circumstances, and an object thereof is to provide a printing method using an offset printing press having excellent image formability.

Solution to Problems



[0019] As a result of intensive research of the present inventor to solve the above problem, the present inventor has found that the above problem can be solved, unexpectedly, by positively making the printing speed of the offset printing slower than an ordinary printing speed and making the film thickness of UV curable ink constant, and has completed the present invention.

[0020] The present invention lies in a printing method using an offset printing press as defined in claim 1. Preferred embodiments of the present invention are defined in the dependent claims.

Advantageous Effects of Invention



[0021] In the printing method using an offset printing press of the present invention, since the printing speed of offset printing is made so slow as to be within a predetermined range, transferability of UV curable ink from a waterless plate to a blanket and transferability of UV curable ink from a blanket to a substrate can be improved.

[0022] For example, since the printing speed is slow, the density of UV curable ink can be increased, and the transfer amount of the UV curable ink can also be increased. Thus, the film thickness of the UV curable ink is in a range of 3 to 7 µm.

[0023] In addition, since the film thickness is in the range of 3 to 7 µm, it is possible not only to improve decorativeness but also to use various functional inks and let the inks exert their functions sufficiently.

[0024] Further, since the printing speed is slow, UV irradiation can be sufficiently performed, so that the curing strength of cured UV curable ink can be raised up to a level capable of withstanding post-process sufficiently.

[0025] In the printing method using an offset printing press of the present invention, since a waterless plate is used, a variation in image quality due to the amount of dampening water or emulsification of water and UV curable ink can be prevented.

[0026] In addition, since the waterless plate is used, the influence of static electricity on an image area (an area to be printed) can be made as small as possible. Thus, a non-antistatic material, such as molding material, can be automatically fed and conveyed without any problems.

[0027] In the printing method using an offset printing press of the present invention, since the UV curable ink is used, the post-process can be started immediately after UV irradiation, and consequently the delivery time can be shortened.

[0028] In view of these matters, according to the printing method using an offset printing press of the present invention, a printed substrate having excellent image formability is obtained.

[0029] In the printing method using an offset printing press of the present invention, since the printing speed is within the range as defined in claim 1 when the substrate is a non-water-absorbing synthetic paper, a plastic film, or a paperboard, image formability can be improved, and, since the UV curable ink is used, offset printing can be performed at a speed that does not impose a burden on the speed of post-process.

[0030] In the printing method using an offset printing press of the present invention, since the ink conveying roll group includes a temperature-regulating ink conveying roll for regulating the temperature of the UV curable ink, and hot water flows through a core portion of the temperature-regulating ink conveying roll, the temperature of UV curable ink applied can be regulated by heating or cooling. It should be noted that if the printing speed is fast, UV curable ink is heated by frictional heat and becomes easy to transfer, but, like the present invention, when the printing speed is low, the UV curable ink is not heated and consequently difficult to transfer. Therefore, UV curable ink needs to be heated.

[0031] In this regard, the temperature of UV curable ink in use is regulated to a range of 20°C to 50 °C, and the viscosity of UV curable ink in use is set in a range of 5 Pa ·s to 1500 Pa ·s.

[0032] In the printing method using an offset printing press of the present invention, since a U-shaped guide is provided below the conveying roll along the shape of the conveying roll, such an event can be prevented as occurrence of a wrinkle on a substrate between the conveying rolls due to hanging-down of a part of the substrate. It should be noted such an event does not occur if the printing speed of offset printing is fast because rotational momentum of the conveying roll causes the substrate to wrap around the conveying roll.

[0033] In this regard, since air is blown to between the conveying roll and the guide, the substrate can be further prevented from hanging down.

[0034] In the printing method using an offset printing press of the present invention, when post-process is performed after offset printing and UV irradiation are performed, a printed substrate having excellent decorativeness can be obtained. In this regard, when the post-process is silk-screen printing, since the printing speed of offset printing and the printing speed of silk-screen printing can be equalized, offset printing and silk-screen printing can be performed in succession.

Brief Description of Drawings



[0035] 

Figure 1 is a schematic view showing an offset printing press used in a printing method according to an embodiment of the present invention; and

Figure 2 is a flowchart showing a printing method using an offset printing press according to an embodiment of the present invention.


Description of Embodiments



[0036] With reference to the drawings, if necessary, a preferred embodiment of the present invention will be described below in detail. Incidentally, in the drawing, identical elements are denoted by identical reference signs, so that a duplicated description is omitted. In addition, a positional relationship, such as top and bottom or right and left, is based on a positional relationship shown in the drawing, unless otherwise noted. Further, the ratio of dimensions on the drawings is not limited to the illustrated ratio of dimensions.

[0037] Fig. 1 is a schematic view showing an offset printing press used in a printing method according to an embodiment of the present invention.

[0038] As shown in Fig. 1, an offset printing press 10 has a plurality of conveying rolls 6 for conveying a substrate 8, a blanket 3 positioned adjacent to the conveying roll 6, a waterless plate 2 positioned adjacent to the blanket 3, an ink conveying roll group 1 positioned adjacent to the waterless plate 2, and a UV irradiation apparatus 5 for irradiating the printed substrate 8 with UV

[0039] In this regard, the ink conveying roll group 1 is an assembly of inking rolls or anilox rolls. It should be noted that the ink conveying roll group 1 may be an assembly of only inking rolls, may be an assembly of only anilox rolls, or may be an assembly of a mixture of both.

[0040] In the offset printing press 10, the conveying rolls 6 adjacent to each other rotate in arrow directions with the substrate 8 therebetween, thereby conveying the substrate 8.

[0041] In addition, ink conveying rolls constituting the blanket 3, the waterless plate 2, and the ink conveying roll group 1, and a temperature-regulating ink conveying roll described later are all cylindrical, and rotate in different directions or identical directions according to the directions of rotation of the conveying rolls 6.

[0042] During rotation, UV curable ink is transferred.

[0043] In the offset printing press 10, as described above, the ink conveying roll group 1 is composed of a plurality of ink conveying rolls and temperature-regulating ink conveying rolls 1a disposed among the ink conveying rolls.

[0044] The temperature-regulating ink conveying roll la has a sheath core structure that is so hollow at a core portion that hot water flows through the core portion. Thus, the temperature of UV curable ink is regulated. It should be noted that if it is unnecessary to heat UV curable ink with hot water, it is unnecessary to cause hot water to flow through the temperature-regulating ink conveying roll, or, conversely, if cooling is needed, it is also possible to cause cold water to flow therethrough.

[0045] Incidentally, the ink conveying rolls are inking rolls or anilox rolls, and the temperature-regulating ink conveying roll is an inking roll or an anilox roll having the sheath core structure in the same manner as described above.

[0046] In the offset printing press 10, a U-shaped guide 4 is provided below the conveying roll 6 along the shape of the conveying roll 6. Thus, such an event can be prevented as occurrence of a wrinkle on the substrate 8 due to that a part of the substrate 8 hangs down to be caught in a folded state of the substrate 8 in between the conveying rolls 6.

[0047] In addition, air is blown to between the conveying roll 6 and the guide 4 by a blower (not shown) or the like in order to prevent the substrate 8 from hanging down. Thus, the substrate can be further prevented from hanging down.

[0048] In this regard, it is preferred that the substrate 8 be a non-water-absorbing synthetic paper, a plastic film, or a paperboard.

[0049] Using these substrates 8 makes it possible to reduce the weight of a product (a printed substrate) and to give the product durability.

[0050] Incidentally, the plastic film to be used can be, but is not particularly limited to, a polyester film, a polyethylene film, a polyethylene naphthalate film, a polypropylene film, a polyamide film, a polyimide film, a polyvinyl alcohol film, a polyvinyl chloride film, a polyvinylidene chloride film, a polycarbonate film, a polystyrene film, a polyacrylonitrile film, an ethylene-vinyl acetate copolymer film, an ethylene-vinyl alcohol copolymer film, an ethylene-methacrylic acid copolymer film, a cellulose triacetate film, an ionomer film, cellophane, or the like.

[0051] In the offset printing press 10, UV curable ink is applied to the waterless plate 2 by the ink conveying roll group 1, and printing is performed on the substrate 8 via the waterless plate 2 and the blanket 3. The details will be described later.

[0052] In the offset printing press 10, UV curable ink is here used.

[0053] Since the UV curable ink is used, post-process can be started immediately after irradiation with UV, and consequently the delivery time can also be shortened.

[0054] At this time, as described above, since the waterless plate 2 is used as the printing plate, it is preferred that the UV curable ink be lipophilic.

[0055] Using the lipophilic UV curable ink has the advantage that the UV curable ink is well dissolved in a lipophilic portion constituting a pattern on the waterless plate 2.

[0056] The UV curable ink includes a UV curable resin, a polymerization initiator, and a pigment. Incidentally, the UV curable ink may further include such an additive as a solvent, a sensitizer, a polymerization inhibitor, an antifoamer, or a surfactant.

[0057] The UV curable resin can be an acrylate, methacrylate, or unsaturated polyester resin having a polymerizable ethylenic double bond, or the like. More specifically, the UV curable resin can be polyester acrylate, epoxyacrylate, urethane acrylate, or the like.

[0058] The polymerization initiator can be a benzopenone, benzoin, acetophenone, or thioxanthone polymerization initiator, or the like.

[0059] In addition, as described later, since the film thickness of the UV curable ink can be made sufficiently thick, the UV curable ink can include functional ink.

[0060] The functional ink can be conductive ink, insulating ink, thermochromic ink, water color-developing hydrophilic ink, perfume ink, UV-ray color-developing ink, fluorescent ink, light-accumulating ink, or the like. These inks all need leveling in a thick film in order to exert their functions. It should be noted that their functions are not exerted unless these inks are dried to certain extents.

[0061] Therefore, when the functional ink is used, it is possible not only to improve decorativeness but also to let the functional ink exert its function sufficiently.

[0062] The temperature of the UV curable ink in use is in a range of 20°C to 50 °C. It should be noted that the temperature is regulated by the temperature-regulating ink conveying roll la described above.

[0063] In addition to the temperature of the UV curable ink in use being within the above range, the viscosity of the UV curable ink in use is in a range of 5 Pa ·s to 1500 Pa ·s.

[0064] When the physical properties of the UV curable ink in use are within the above ranges, transfer of the UV curable ink to the waterless plate 2, transfer of the UV curable ink to the blanket 3, and transfer of the UV curable ink to the substrate 8 can be performed securely and stably.

[0065] The UV irradiation apparatus 5 is a device for irradiating the printed substrate with UV.

[0066] The UV irradiation apparatus 5 is not limited to a specific one, and a commercially-available one can be used according to situations.

[0067] Incidentally, the UV irradiation apparatus 5 may be disposed inside the offset printing press 10, for example, between cylinders, or may be disposed outside.

[0068] Fig. 2 is a flowchart showing a printing method using an offset printing press according to an embodiment of the present invention.

[0069] As shown in Fig. 2, a printing method using the offset printing press 10 has an offset printing step S1 of printing UV curable ink on the substrate 8 after transferring the UV curable ink applied to the waterless plate 2 to the blanket 3 by means of the ink conveying roll group 1, and a UV irradiating step S2 of irradiating the printed substrate 8 with UV to cure the UV curable ink.

[0070] In the printing method using the offset printing press 10, the offset printing step S1 and the UV irradiating step S2 are performed in succession.

[0071] At the offset printing step S1, UV curable ink is applied to the waterless plate 2 by means of the ink conveying roll group 1.

[0072] In this regard, in the printing method using the offset printing press 10, since the ink conveying roll group 1 is used, when the UV curable ink is applied to the waterless plate 2, a constant amount of ink can be stably supplied to the waterless plate 2 even at a low printing speed.

[0073] In addition to this, mist occurs when an inking roll is used, but the mist can be prevented from occurring by means of the ink conveying roll group.

[0074] In addition, in the printing method using the offset printing press 10, since the waterless plate is used, a variation in image quality due to the amount of dampening water or emulsification caused by water and the UV curable ink can be prevented.

[0075] In addition to this, the influence of static electricity on an image area (an area to be printed) can be reduced.

[0076] Then, the UV curable ink applied to the waterless plate 2 is transferred to the blanket 3 made of rubber, and thereafter printed on the substrate 8.

[0077] At this time, the running speed of the substrate 8 is a low speed. It should be noted that the running speed of the substrate 8 and the printing speed onto the substrate 8 are identical with each other. Therefore, by making the running speed of the substrate 8 low, the speed of printing onto the substrate 8 becomes lower.

[0078] Specifically, the running speed of the substrate 8 is in a range of 250 m/h to 1700 m/h, preferably, in a range of 250 m/h to 1500 m/h.

[0079] By setting the running speed of the substrate 8 in this range transferability of the UV curable ink from the waterless plate 2 to the blanket 3, and transferability of the UV curable ink from the blanket 3 to the substrate 8 can be improved. Incidentally, the printing speed in a commercially-available ordinary offset printing press is 3000 m/h at the lowest.

[0080] Further, the density of the UV curable ink can be increased, and the transfer amount can be increased. Thus, the film thickness can be increased.

[0081] Specifically, in the printing method using the offset printing press 10, the film thickness of applied UV curable ink is in a range of 3 to 7 µm. Incidentally, the film thickness of UV curable ink in an ordinary offset printing press is in a range of 1 to 2 µm.

[0082] Thus, since the film thickness is in a range of 3 to 7 µm, it is possible not only to improve decorativeness but also to use various functional inks and let the inks exert their functions sufficiently.

[0083] Further, sufficient UV irradiation can be performed, so that the strength of the cured UV curable ink can be increased up to a level capable of withstanding post-process sufficiently.

[0084] In the offset printing press 10 according to the embodiment, as described above, since the substrate 8 is a non-water-absorbing synthetic paper, a plastic film, or a plastic sheet, and the printing speed is set within the above range, image formability can be improved, and, as described above, since the UV curable ink is used, offset printing can be performed at a speed that does not impose a burden on the speed of post-process.

[0085] Incidentally, if a water-absorbing substrate is used and the printing speed is low, the water-absorbing synthetic paper absorbs moisture in the air, and UV curable ink applied thereto may bleed.

[0086] At the UV irradiating step S2, the UV curable ink is cured by irradiating the printed substrate 8 with UV.

[0087] The UV irradiating method is not limited to a particular one, and a conventional known method can be used.

[0088] According to the printing method using the offset printing press 10 according to the embodiment, a printed substrate having excellent image formability is obtained through the above steps.

[0089] In the offset printing press 10 according to the embodiment, it is preferred that post-process is performed after the offset printing step S1 and the UV irradiating step S2 are performed in succession. That is, it is preferred that the post-process be performed after the offset printing is performed and the UV irradiation is performed. In this case, a printed substrate having excellent decorativeness can be obtained.

[0090] The post-process can be, for example, silk-screen printing, flexography, roller coating, coating, molding, or the like.

[0091] Among these, the post-process is preferably silk-screen printing. In this case, a printed substrate having excellent decorativeness can be obtained. In this case, the printing speed of offset printing and the printing speed of silk-screen printing can be made equal to each other, so that offset printing (the offset printing step S1 and the UV irradiating step S2) and silk-screen printing can be performed in succession.

Industrial Applicability



[0092] The present invention is used as a printing method using an offset printing press applying UV curable ink to a substrate. According to the printing method using the offset printing press of the present invention, a printed substrate having excellent image formability is obtained.

Reference Signs List



[0093] 

1...ink conveying roll group,

1a...temperature-regulating ink conveying roll,

2...waterless plate,

3...blanket,

4...guide,

5...UV irradiation apparatus,

6...conveying roll,

8...substrate,

10...offset printing press,

S1...offset printing step,

S2...UV irradiating step,




Claims

1. A printing method using an offset printing press (10) including a plurality of conveying rolls (6) for conveying a substrate (8), a U-shaped guide (4) provided below the conveying rolls (6) along the shape of the conveying rolls (6) a blanket (3) positioned adjacent to the conveying rolls (6), a waterless plate (2) positioned adjacent to the blanket (3), an ink conveying roll group (1) positioned adjacent to the waterless plate (2), and a UV irradiation apparatus (5) for irradiating the printed substrate (8) with UV, the printing method comprising:

an offset printing step (S1) of transferring UV curable ink applied to the waterless plate (2) to the blanket (3), and then printing the UV curable ink on the substrate (8); and

a UV irradiating step (S2) of irradiating the printed substrate (8) with UV to cure the UV curable ink, wherein

the running speed of the substrate (8) is in a range of 250 m/h to 1700 m/h; the film thickness of the applied UV curable ink is in a range of 3 to 7 µm;

the ink conveying roll groups (1) is an assembly of inking rolls or anilox rolls; and

the ink conveying roll group (1) comprises a temperature-regulating ink conveying roll (1a) for regulating the temperature of the UV curable ink by allowing hot water to flow through a core portion of the temperature-regulating ink conveying roll (1a), the UV curable ink is heated so that the temperature of the UV curable ink in use is regulated to a range of 20 °C to 50 °C and the viscosity of the UV curable ink in use is set in a range of 5 Pa·s to 1500 Pa·s, and air is blown to between the conveying roll (1a) and the guide (4) so as to prevent the substrate (8) from hanging down.


 
2. The printing method using an offset printing press (10) according to claim 1, wherein the substrate (8) is a non-water-absorbing synthetic paper, a plastic film, or a paperboard.
 
3. The printing method using an offset printing press (10) according to claim 1 or 2, wherein the UV curable ink is lipophilic.
 
4. The printing method using an offset printing press (10) according to any one of claims 1 to 3, wherein post-process is performed after offset printing is performed and UV irradiation is performed.
 
5. The printing method using an offset printing press (10) according to claim 4, wherein the post-process is silk-screen printing.
 


Ansprüche

1. Druckverfahren unter Verwendung einer Offset-Druckmaschine (10) aufweisend eine Vielzahl von Transportwalzen (6) zum Transportieren eines Substrats (8), eine U-förmige Führung (4), die unter den Transportwalzen (6) entlang der Form der Transportwalzen (6) bereitgestellt ist, ein an die Transportwalzen (6) angrenzend positioniertes Drucktuch (3), eine an das Drucktuch (3) angrenzend positionierte wasserlose Druckplatte (2), eine an die wasserlose Druckplatte (2) angrenzend positionierte Druckfarbentransportwalzengruppe (1) und eine UV-Bestrahlungseinrichtung (5) zum Bestrahlen des bedruckten Substrats (8) mit UV, wobei das Druckverfahren die folgenden Schritte umfasst:

einen Offsetdruckschritt (S1) des Übertragens von auf die wasserlose Druckplatte (2) aufgebrachter UVhärtender Druckfarbe auf das Drucktuch (3) und dann Drucken der UV-härtenden Druckfarbe auf das Substrat (8); und

einen UV-Bestrahlungsschritt (S2) des Bestrahlens des bedruckten Substrats (8) mit UV zum Aushärten der UV-härtenden Druckfarbe, wobei

die Durchlaufgeschwindigkeit des Substrats (8) in einem Bereich von 250 m/h bis 1700 m/h liegt;

die Filmdicke der aufgebrachten UV-härtenden Druckfarbe in einem Bereich von 3 bis 7 µm liegt;

die Druckfarbentransportwalzengruppen (1) eine Baugruppe von Farbwalzen oder Anilox-Walzen ist; und

die Druckfarbentransportwalzengruppe (1) eine Temperaturregeldruckfarbentransportwalze (1a) zum Regeln der Temperatur der UV-härtenden Druckfarbe, indem heißem Wasser Durchfließen durch einen Kernteil der Temperaturregeldruckfarbentransportwalze (1a) ermöglicht wird, umfasst und die UV-härtende Druckfarbe aufgeheizt wird, so dass die Temperatur der UV-härtenden Druckfarbe im Gebrauch in einem Bereich von 20°C bis 50°C geregelt wird und die Viskosität der UV-härtenden Druckfarbe im Gebrauch auf einen Bereich von 5 Pa·s bis 1500 Pa·s eingestellt wird und Luft zwischen die Transportwalze (1a) und die Führung (4) geblasen wird, um somit das Substrat (8) am Herunterhängen zu hindern.


 
2. Druckverfahren unter Verwendung einer Offset-Druckmaschine (10) nach Anspruch 1, wobei das Substrat (8) ein kein Wasser absorbierendes synthetisches Papier, ein Kunststofffilm oder ein Karton ist.
 
3. Druckverfahren unter Verwendung einer Offset-Druckmaschine (10) nach Anspruch 1 oder 2, wobei die UV-härtende Druckfarbe lipophil ist.
 
4. Druckverfahren unter Verwendung einer Offset-Druckmaschine (10) nach einem der Ansprüche 1 bis 3, wobei Nachverarbeitung durchgeführt wird, nachdem Offsetdrucken durchgeführt wurde und UV-Bestrahlung durchgeführt wurde.
 
5. Druckverfahren unter Verwendung einer Offset-Druckmaschine (10) nach Anspruch 4, wobei die Nachverarbeitung Siebdrucken ist.
 


Revendications

1. Procédé d'impression utilisant une presse d'impression offset (10) comportant une pluralité de rouleaux de transport (6) pour transporter un substrat (8), un guide en forme de U (4) disposé sous les rouleaux de transport (6) le long de la forme des rouleaux de transport (6), un blanchet (3) positionné au voisinage des rouleaux de transport (6), une plaque sans mouillage (2) positionnée au voisinage du blanchet (3), un groupe de rouleaux de transport d'encre (1) positionné au voisinage de la plaque sans mouillage (2), et un appareil d'irradiation UV (5) pour irradier le substrat imprimé (8) avec des UV, le procédé d'impression comprenant :

une étape d'impression offset (S1) consistant à transférer de l'encre durcissable aux UV appliquée à la plaque sans mouillage (2) au blanchet (3), et imprimer ensuite l'encre durcissable aux UV sur le substrat (8) ; et

une étape d'irradiation UV (S2) consistant à irradier le substrat imprimé (8) avec des UV pour durcir l'encre durcissable aux UV, dans lequel

la vitesse d'avance du substrat (8) se situe dans une gamme de 250 m/h à 1700 m/h ;

l'épaisseur de film de l'encre durcissable aux UV appliquée se situe dans une gamme de 3 à 7 µm ;

le groupe de rouleaux de transport d'encre (1) est un ensemble de rouleaux d'encrage ou de rouleaux anilox ; et

le groupe de rouleaux de transport d'encre (1) comprend un rouleau de transport d'encre à régulation de température 1a) pour réguler la température de l'encre durcissable aux UV en faisant circuler de l'eau chaude à travers une partie centrale du rouleau de transport d'encre à régulation de température (la), l'encre durcissable aux UV est chauffée de telle sorte que la température de l'encre durcissable aux UV à l'usage est régulée dans une gamme de 20 °C à 50 °C et la viscosité de l'encre durcissable aux UV à l'usage est réglée dans une gamme de 5 Pa·s à 1500 Pa·s, et de l'air est soufflé entre le rouleau de transport (1a) et le guide (4) de manière à empêcher le substrat (8) de pendre.


 
2. Procédé d'impression utilisant une presse d'impression offset (10) selon la revendication 1, dans lequel le substrat (8) est un papier synthétique n'absorbant pas l'eau, un film plastique, ou un carton.
 
3. Procédé d'impression utilisant une presse d'impression offset (10) selon la revendication 1 ou 2, dans lequel l'encre durcissable aux UV est lipophile.
 
4. Procédé d'impression utilisant une presse d'impression offset (10) selon l'une quelconque des revendications 1 à 3, dans lequel un post-traitement est effectué après que l'impression offset a été effectuée et que l'irradiation UV a été effectuée.
 
5. Procédé d'impression utilisant une presse d'impression offset (10) selon la revendication 4, dans lequel le post-traitement est une sérigraphie.
 




Drawing









REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description