The present invention relates to a printing device for performing multi-color gravure offset printing on printing materials with various shapes in one rotation (hereinafter, referred to as one printing cycle) of a gravure offset roll and a method thereof, and more specifically, to a multi-color gravure offset printing device which appropriately prints various colors on a material having a flat surface, a three-dimensional stereoscopic printing material having a curved structure, including a plastic bottle shape or an asymmetrical shape with thickness, a three-dimensional stereoscopic material made by a three-dimensional (3D) printer, and the like, in an overlapping manner and which dries the multi-color gravure printed materials after the multi-color gravure printing is performed in one printing cycle, and a printing method.
Multi-color gravure offset printing methods include a method of installing a plurality of plates around a drum with a single large radius described in Japanese Patent Application Laid-Open No. H09-277491 and a method of disposing a plurality of drums in parallel to each other (Japanese Patent Application Laid-Open No. 2008-168578), and the like. However, recently, there are problems with adjusting a position of a drum itself and ensuring reproducibility, maintaining precision and reproducibility of printing at a width of less than or equal to 100 μm when the printing material is moved in a conveyor manner, and the like. Further, it is highly likely that various problems with precision caused when a plurality of drums are used, such as distortion of parallel precision of installation positions of the plurality of drums caused by change in temperature, determination of parallel position, and the like, will occur. Although the width is less than or equal to 100 μm, due to the thickness being a few micrometers, there are problems, such as excessive electric resistance or a lack of sufficient color density. Furthermore, in the high functional printing device satisfying the problem, there are problems of difficulty of automation and parallel processing or change in quality of printing occurring during printing as time elapses from the view point of economically high efficiency printing. There are many factors that block supply of gravure offset printing when compared to a silk printing method, including a problem in which the roll is damaged due to solidification of a ultra violet (UV) ink in a drying process when UV rays touch a part of blanket roll and a problem in which printing is distorted due to a thickness of printing in a serial printing method.
The present invention is directed to providing a printing device for performing gravure offset printing on materials having a flat surface and a stereoscopic shape, such as a cylindrical surface or a three-dimensional surface, using one blanket roll in one printing cycle (hereinafter, referred to as one rotation of a blanket roll), and a method thereof.
The present invention is also directed to providing a printing device for printing various colors that a printer may print within one printing cycle.
One aspect of the present invention provides a gravure offset printing device which includes a blanket roll having a cylindrical shape and moving in a first direction while rotating, an ink transfer unit including at least one ink transfer plate which is in contact with a lower end of the blanket roll, and a squeeze unit moving in a second direction while one end thereof is in contact with the ink transfer plate, wherein the second direction is inclined a predetermined angle or orthogonal to the first direction.
Another aspect of the present invention provides a gravure offset printing device which includes a blanket roll, wherein ink is transferred to a surface of the blanket roll and the blanket roll horizontally moves in a first direction while rotating and a printing material positioned to face the blanket roll in the first direction, wherein the printing material moves a predetermined length in the first direction.
According to the present invention, gravure offset printing can be performed on printing materials in various shapes in one printing cycle. Particularly, the gravure offset printing can be performed even on a three-dimensional stereoscopic printing material with thickness including a cylindrical printing material and a curved structure as well as a flat printing material.
According to the present invention, inks of various colors can be printed at the same position on each printing material to overlap each other, and thus a required color can be printed in one printing cycle by combining the colors of ink.
Further, according to the present invention, since mass printing can be performed on a plurality of printing materials in one printing cycle, a speed of printing can be increased, and thus economic feasibility can be increased.
A gravure offset printing device, which is a gravure offset printing device, including a blanket roll having a cylindrical shape and horizontally moving in a first direction while rotating, and at least one ink transfer plate which is in contact with a lower end of the blanket roll, includes a blade moving in a second direction while one end thereof is in contact with the ink transfer plate, wherein the second direction has a predetermined angle with respect to the first direction.
Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.
The gravure offset printing device of the present invention includes a blanket roll 100 having a cylindrical shape and moving along a pair of straight rails, which are parallel to each other, while rotating, an ink supplying unit 200 uniformly applying ink to an ink transfer unit, at least one ink transfer unit 300 positioned in contact with a lower end of the blanket roll and transferring the ink to the blanket roll in a printing pattern to be printed, and a printing unit 400 which is positioned in front of the blanket roll in a movement direction and on which a printing material on which the ink (the printing pattern) transferred to the blanket roll is printed is positioned, and further includes a drying unit 600 drying and cooling the ink printed on the printing material.
Hereinafter, the blanket roll 100 will be described in detail.
The blanket roll 100 (hereinafter, referred to as a roll for convenience of description) has a cylindrical shape (precisely, a nearly cylindrical shape having elasticity rather than a complete cylindrical shape, hereinafter referred to as “cylindrical shape” for convenience of description), and moves horizontally in a first direction shown in
A material of the blanket roll 100 is a so-called rubber roll containing, for example, any one of Teflon, silicone, vinyl chloride, urethane, epoxy, and the like, or a combination thereof, as a main component. As another example, the material of the roll may be a combination of the main component and an inorganic element.
The material, which depends on intermolecular force between the ink and a printing material, is closely related to a condition in which a difference between entropies of ink per unit volume and each material of the printing material and the product of pressure and volume is small. Particularly, when the intermolecular force is strong, such a condition actually becomes a required condition.
The material of printing material may be, for example, a great variety of materials such as an elastomer, an organic matter such as plastic, glass, a silicon substrate used for a semiconductor, a solar cell, and the like, a metal, paper, etc.
A Japanese Industrial Standards (JIS)-A hardness of the blanket roll 100 is greater than or equal to 0 and less than or equal to 40 at room temperature (about 25° C.), and particularly, the blanket roll has a thickness 0.5 to 40 times a thickness of a stereoscopic printing material. When a metal shaft, for example aluminum, is in the center of the blanket roll, the thickness of the roll refers to a portion excluding the central metal shaft.
A rotation speed (a movement speed in a first direction) of the roll on a transfer unit 300 while transferring is in a range of 0.5 to 12 m/min. In the gravure offset printing, the rotation speed of the roll, which is very important when ink is transferred to the blanket roll, satisfies fluid movement equation for ink. Such a feature is a fundamental difference from a pad printing method, a tampo printing method, or a screen printing method.
That is, since the blanket roll has an appropriate length of Nip, it is preferable that a roll with small intermolecular force has a speed of 0.5 to 12 m/min in a first direction when roll printing is performed in order to secure an increasing fluid physical movement of the ink according to a necessity, for example in the case of conductive ink containing a noble metal such as silver.
Further, it is preferable that the intermolecular force between the ink transferred to the roll and the printing material is selected based on the entropies and the like. Thus, the movement of the ink used for printing can be facilitated and optimized.
Furthermore, as a main difference between the method according to the present invention and other printing methods, the present invention includes a method of precisely transferring ink from a plate to a gravure roll to secure precise reproducibility, and thus complicated overlapping printing can be easily performed at high speed as described below.
Hereinafter, the ink supplying unit 200 will be described in detail with reference to
Only one color of ink I may be used, but in the present invention, a plurality of colors (ink portions I1, I2, I3, and I4 in four colors in the accompanying drawings and following embodiments) are used, assuming multi-color printing. As seen in
The inks in various colors simultaneously fall down (drip down) through a plurality of ink syringes 210 disposed at predetermined gaps L+Δ. The plurality of ink syringes 210 are moved by a horizontal moving unit, such as a linear actuator or the like, by a width L of the required ink in the first direction (x direction) so that the inks linearly fall down. Further, the ink is referred to as a various colored ink, but in one embodiment of the present invention includes a transparent inorganic matter, such as varnish, in addition to ink or ink having a different feature although it has the same color.
A blade of a squeeze unit 230 moves while being in contact with a transfer plate 310 of the ink transfer unit in a second direction y orthogonal to (or a predetermined angle) a movement direction (a first direction x) of the blanket roll 100, and an engraved pattern in the transfer plate is filled with the ink linearly supplied by the ink syringe.
In this case, a width of the supplied ink should be adjusted so that various colors are not mixed. In the embodiment of the present invention, for simplicity of description, both a width of supplied ink and a width of an ink transfer plate 310 in which the engraved pattern is formed are described as L. That is, the inks are linearly supplied by the width L of the ink transfer plate 310, but the ink portions may not have the same width L according to a purpose thereof.
As shown in
Hereinafter, a squeeze process of filling an engraved pattern in the ink transfer plate 310 with ink through a blade will be described with reference to
Preferably, the ink transfer plate 310 may be a metal plate, a resin film, or the like in which a fine engraved pattern may be formed.
The ink transfer unit 300, configured to transfer ink in an engraved pattern 311 to a surface of the blanket roll 100, includes at least one ink transfer plate 310 fixed on the plate-shaped support 330. Since the ink transfer plate 310 transfers the ink to the roll 100, the ink transfer plate should be fixed at an exact position to perform multi-color printing as described below.
As a first fixing method of fixing the ink transfer plate 310 on the support, the method may allow the ink transfer plate 310 made of a film material to be fixed on the support 330 not to move by generating a vacuous pressure generated by a vacuum generating unit, which is not shown, through a vacuous hole 335. As a second fixing method, the ink transfer plate 310 may be fixed on the support by a double-sided tape 336. Further, as a third fixing method, the ink transfer plate may be fixed by a fixing unit, a rotation fixing screw, or the like, on the support.
In
The ink transfer plate 310 has the engraved pattern 311. A method of forming the engraved pattern in a resin film includes an imprinting method which is already widely known. The imprinting method is well known, and thus detailed description thereof will be omitted.
The squeeze unit 230 allows the fine engraved pattern 311 to be filled with ink while pushing the ink I in the second direction while one end thereof is in contact with the ink transfer plate 310 like a doctor blade having a straight-type one end.
In the exemplary embodiments of the present invention, a part of one end of the blade may have various shapes to correspond a protruding portion or concave parts 331, 332, and 333 of the support 330 formed to prevent colors of the inks from being mixed.
In
To solve the problem, the transfer plate support 330 includes the concave parts 331 and 333 or the protruding part 332 formed in the gaps Δ to extend in the second direction, thereby preventing the inks from being mixed.
In this case, a part of one end of the blade part may have a shape of the protruding part 232 or the concave part 231 to correspond to the shape of the concave part or the protruding part. When the transfer plate support has shapes of the concave parts 331 and 333, it is not necessary for a part of the blade to not have a shape of the concave part 231. When the transfer plate support has a shape of the protruding part 332, it is preferable that a part of one end of the blade has a shape of the concave part 232 corresponding to the shape of the concave part 332 of the support for easy movement of the blade part.
As another exemplary embodiment, an auxiliary roller and the like may be provided for appropriately cleaning ink remaining after the fine engraving pattern is filled with ink through the blade part. The auxiliary roller, which automatically cleans the ink on the blade part, may be set to clean the ink of the blade part every predetermined number of squeezes according to a viscosity of ink or an amount of used ink.
Another embodiment of a squeeze blade part according to the present invention will be described with reference to
The squeeze blade part of the ink supplying unit 200, as shown in
Hereinafter, an operation of the double blade part will be described with reference to
According to configurations of the double blades shown in
Further, the blade part allows a waste, a wiper, KimWipes, or the like, which is disposed outside a range of the roll movement in the second direction, to independently clean the blade without consumption of printing time while printing on the printing material if necessary, and thus clean printing may be achieved.
Further, a starting ink line linearly supplied on the transfer plate from an ink supply starting point to an ending point, which is a movement range of the ink supplying unit, is not in a range of roll movement when the roll moves in the first direction. That is, the ink supplying unit 200 moving in the second direction performs a squeezing operation using the blade by supplying the ink to the transfer plate and moving in the second direction.
Further, when the blade is detached from the ink in the final squeezing, the ink remaining behind the blade is divided into the transfer plate or the blade according to the intermolecular force due to intermolecular force among molecules of the blade, the transfer plate, and the ink and becomes a remaining ink line. Similar to the starting ink line, a position of the final blade (a position of the remaining ink line) in squeezing should not be in a range of roll movement in the first direction. Therefore, a movement distance in the second direction of the blade should be more than a length of the second direction of the roll so as not to be in a range of roll movement.
The roll moves on the transfer plate while transferring the ink so that the starting ink line and the remaining ink line are not in a range of movement in the first direction.
Since the roll enters a printing area through a transfer area, each of the squeeze unit and the ink supplying unit may individually move, and an operation of supplying ink to the transfer plate can be performed for the next printing as described above.
To reduce the remaining ink line, as described above, operations of moving a blade and squeezing in the direction opposite to the second direction are additionally performed, and thus quality of printing can be maintained, the roll can be protected, and economic feasibility of ink supply can be increased.
In
Based on this, a radius r of the roll 100 shown in
In this case, N refers to the number of colors used for printing or the number of colors when a stereoscopic printing material has a different shape but the same color, for example, when the stereoscopic printing material is printed with the same color in an overlapping manner once more by rotating in a θ direction. N may be the number of transfer plates. For example, in the embodiment in
As described above, L refers to a width of ink applied on the transfer plate, the ink has the same width on each of the transfer plates under the assumption that the width is the same even when printing is performed in different directions without rotation in the θ direction for simplicity of formula, and A refers to a gap between the transfer plates (ink) for preventing colors of the inks from being mixed. In this case, δ refers to a fine correction amount depending on a pressure of the roll by a minimum change (Nip) in a radius generated when an elastic roller is in contact with the transfer plate and the printing material. In the case (δ=0) of an extreme case in which the above-described Nip is not generated, a circumferential length of the roll 100 is greater than or equal to the sum of lengths in the first direction of the predetermined gaps between the ink transfer plates.
The circumferential length of the blanket roll 100 will be shown by the following formula.
In this case, Li refers to a length in the first direction of the ith transfer plate, and Δj refers to a length of a gap between the jth transfer plate and the next plate in the first direction.
In
As described at a bottom of
The printing unit 400 is positioned in front of the roll 100 to which the ink is transferred through the transfer unit 300 in the movement direction (the first direction) between the pair of guide rails. In
As the method of fixing the printing material 410, when the printing material has a flat surface, a position fixing member, such as a double-sided tape, a fixing unit, and the like, or a vacuum pressure may be used in the same manner as the above-described transfer plate. However, when the printing material 410 is a stereoscopic printing material, it is preferable that a separate fixing member 430 is provided to fix the stereoscopic printing material on the support 420. To print a large amount of printing material, it is necessary that the printing material is easily attached to or detached from the support, and a position of the printing material should be firmly fixed during printing. According to the exemplary embodiment, the fixing member 430 is an organic matter, such as plastic, manufactured by a three-dimensional (3D) printer and having a shape corresponding to an inner surface of the printing material. When the fixing member is manufactured by the 3D printer, a fixing member optimized for printing materials of various shapes can be easily manufactured.
Further, as a main feature of the present invention, color printing and coloring can be performed on a three-dimensional stereoscopic material manufactured by a 3D printer.
The printing material support 420 may be inclined, by the rotating unit 460, a predetermined angle φ upward or downward with respect to the first direction, for example, a motor and the like, provided on both sides or one side of the printing material support 420 (hereinafter, referred to as a vertical rotation of the printing material). The configuration is very effective particularly when the printing material is a stereoscopic printing material with thickness (see
In
In this case, since a contact point between the printing material and the roll is changed according to an inclination of the printing material, the printing material should be inclined while maintaining an optimal printing distance. In
The printing unit 400 includes the printing unit height adjusting unit 450 provided at a lower end thereof so as to adjust a vertical height of the printing material support 420. Further, the printing unit further includes a separate guide rail separately from the guide rail so that the printing material support 420 moves in the first direction. The printing material support 420 allows a vertical movement performed by the printing unit height adjusting unit 450 and a horizontal movement performed by the guide rail 110 to be performed independently from each other.
In
In
To print the second ink portion I2, the printing material should be moved to a position corresponding to
In the method of printing the second ink portion I2, a difference from the method in
Since the printing material in
As shown in
As described above, assuming that the four ink portions are colors based on a CMYK color table, any color (multi-color) can be printed on the printing material with a required pattern by combining the four inks I1, I2, I3, and I4. Above all, multi-color printing can be performed in one printing cycle (one rotation of the roll 100), and thus printing time can be reduced, and mass production can be performed.
Referring to
For example, when a length in the second direction of the printing material 410 is short, a plurality of printing materials may be disposed in the second direction orthogonal to a movement direction (the first direction) of the roll 100. When a length in the first direction of the printing material 410 is short, or a printing pattern is the same in a whole ink area, a plurality of printing materials may be disposed in the first direction. In any of the cases, the sum of lengths in the first direction of all printing materials should be less than or equal to L. When a size of printing material itself is much smaller than one ink portion, the printing materials are disposed in parallel in both the first and second direction, and thus productivity per one printing cycle can be increased.
Although the above-described printing method is relatively simply described, it is preferable that UV irradiation is quickly performed after printing of each color to prevent the printed ink portion from being moved to other ink portions on the roll. Generally, photon energy is selectively applied to a molecule on an originally low energy orbit of antibonding orbital π* to cause a transition of an electron so as to increase overlap probability of an electron cloud and make an reaction, and thus ink is cured by UV rays. Therefore, ink with an organic matter matching with a frequency of UV rays can be cured very quickly.
As described above, since various colors or various kinds of inks are printed on the same printing material in one printing cycle to overlap each other, it is necessary that the ink is dried after every color printing and before the ink is printed to overlap. After a process of printing all inks is completed according to a type of inks or a feature of the printing material, the inks can be dried at once. For example, when the same color is re-printed by 0 rotation after the printing, UV irradiation is not necessary.
First, although a configuration of the drying unit is changed according to a feature of ink, in the present invention, it will be assumed that UV ink is used. Since the UV ink can be dried quickly based only on the principle of irradiating UV rays to the ink, a printing speed is increased, thereby facilitating mass production.
As shown in
The drying unit 600 includes a UV irradiating unit 610 irradiating UV rays and a UV blocking unit 620 having a strip-shape and blocking UV rays between the UV irradiating unit 610 and the roll 100 so as not to be irradiated to other positions except the printing material, and particularly, to the roll 100. Selectively, the drying unit 600 may include a cooling unit 630 to prevent the printing material from being degraded, deformed, and discolored due to heat generated by the UV rays.
When the fixed-type drying unit is used as shown in
The drying unit 600 in
The moving-type drying unit 600 shown in
Further, the UV blocking unit 620 for blocking UV irradiation for the roll 100 is disposed between the UV irradiating unit 610 and the roll 100.
Hereinafter, embodiments of the multi-color gravure offset printing device according to the present invention will be described in detail according to three types of printing materials.
First, as a first embodiment, a case in which the printing material is a flat printing material will be described.
Four colors are applied to the inside of the transfer plate 310 installed in the transfer unit 300, and the roll 100 rotates and moves horizontally in the first direction so that ink is transferred to the roll. In the same manner as in the embodiment, a length of each of the ink portions I1, I2, I3, and I4 is L, and the ink portions have a distance Δ formed therebetween. The roll 100 moves horizontally to the printing unit 400 while rotating in the first direction. Hereinafter, the printing material will be described based on the assumption of a flat printing material such as a solar cell. In this case, the printing material is not a flat surface that does not have height variations at all but is a flat surface that does not have height variations significant enough to affect printing (about 1 mm or less), for example a semiconductor surface including paper and a solar cell.
The roll 100 approaches the printing material fixed to the printing plate support by a linear actuator or the like while being put on a slider of the first guide rail. In this case, the flat printing material may be fixed by a fixing unit, such as a double-sided tape, a vacuum, a jig, or the like, in the same manner as the above-described method of fixing the transfer plate. When the roll rotates and moves horizontally in the first direction while a lower end of the roll is in contact with the printing material positioned to face the roll, printing is performed.
When a portion at a predetermined position x1 of the first printed portion I1 is printed (Tx1) on the printing material, the printing material is moved downward by the printing unit height adjusting unit 450 and moves horizontally (and re-moves upward) L+Δ+ε in the first direction while the roll 100 stops rotating and moving horizontally. When a pressure is low not enough to generate Nip of the roll 100 on the flat printing material and the transfer unit, ε is close to 0. When the roll 100 repeatedly rotates and moves horizontally, printing is performed on the second printed portion I2. In this case, since the printing material moves L+Δ+ε in the first direction, a predetermined position x2 of the second printed portion I2 is printed (Tx1x2) to overlap the ink x1. Similarly, since the four printed portions I1, I2, I3, and I4 overlap each other in four layers, multi-color printing can be performed.
As a second embodiment, a case in which the printing material is a cylindrical printing material will be described with reference to
A difference from the first embodiment is that a rotating unit 460 is provided at any one or both ends of the cylindrical printing material oriented in a horizontal direction to rotate the cylindrical printing material 360 degrees an axis in the second direction (a longitudinal direction of the cylindrical printing material). In this case, a rotation direction of the printing material is a direction opposite to the rotation direction of the roll 100. That is, when the roll 100 rotates in a counterclockwise in the embodiment, the cylindrical printing material rotates in a counterclockwise direction (reversely). The rotation of the cylindrical printing material is synchronized with the rotation of the roll 100 so as to be controlled at a constant speed so that a portion at which the cylindrical printing material is in contact with the roll does not slide. Further, the rotating units installed on both ends of the cylindrical printing material include a fixing unit so that the printing material does not slide.
The method of printing the first ink portion I1 is the same as in the first embodiment except that the cylindrical printing material rotates with the roll. That is, the length of the printing material in the second embodiment refers to a circumferential length of the cylinder.
Similar to the first embodiment, the cylindrical printing material vertically moves downward while the roll 100 stops, horizontally and vertically moves to the printed position of the second ink portion I2, and printing preparation of the second ink portion is finished. The roll 100 re-rotates and moves horizontally to return to the same position as the position Tx1 at which the first ink is printed, and the second ink is printed (Tx1x2) with a changed phase of a rotation angle φ of the printing material.
Hereinafter, another embodiment of a cylindrical printing material will be described with reference to
In the above-described second embodiment, since the cylindrical printing material moves downward to print a second printed portion, moves horizontally L+Δ+ε, and re-moves upward, there is a problem in which the printing time is increased up to about 4 πr/V as the time for moving the printing material takes (V is a movement average speed, and r is radius of roll). Further, the printing time is as long as the printing material takes to move to and return from a position at which the drying unit 600 is positioned.
When the printing material is cylindrical, unlike a flat printing material in the first embodiment of the present invention or a stereoscopic printing material in the third embodiment, the cylindrical printing material moves with the roll 100 and rotates while being in contact with the roll 100, and thus multi-color printing can be performed. That is, in the case of another embodiment, the printing material is not horizontally moved while printing is performed on the printing material, but in the case of the cylindrical printing material, the printing material moves in the first direction at the same speed as that of the horizontal movement of the roll 100 while the printed is performed, and it is not necessary to horizontally move the printing material, and thus it is not necessary to move a separate printing material for drying.
Referring to
When the cylindrical printing material and the drying unit move with the roll in the first direction, a necessary operation including moving of the cylindrical printing material in a horizontal direction described in the first embodiment can be reduced, and since it is not necessary to move the cylindrical printing material to the drying unit, multi-color printing and drying can be simultaneously and quickly performed.
Further, particularly when UV rays are irradiated from the right direction in
As the third embodiment, a case in which the printing material is a stereoscopic printing material having various thicknesses in a z-axis will be described. However, since the third embodiment is basically the same as the first and second embodiments, the same descriptions will be omitted.
In the third embodiment, the stereoscopic printing material is a printing material 410 shown in
Therefore, in
However, it may be difficult for the roller moving in the first direction to perform printing on the unprinted surfaces 410c and 410d even using the methods shown in
Hereinafter, a process of printing on a stereoscopic printing material including the processes will be described.
Basically, the ink is transferred from the transfer unit 300 to the roll 100 in the same manner unlike the conventional embodiment, the printing material rotates a predetermined angle about a z-axis, and thus the same ink needs to be used twice. That is, to use four colors on the printing material, in the third embodiment, two inks I and I′ per one ink type I should be applied to eight transfer plates. The inks are transferred from the eight transfer plates to the roll 100. Although there are four transfer plates, two printing patterns may be carved on each of the four transfer plates. Hereinafter, for simplicity of description, description will be made based on the assumption of eight transfer plates.
When the roll approaches the printing material, the first printing I1 of the first ink portion is performed. Similar to
Through the processes, one type of ink is printed on the printing material, and the same ink is re-printed on the printing material horizontally rotating 90°, and thus printing is easily performed on the above-described unprinted surfaces 410c and 410d.
Importantly, to print the same color, a drying process, such as a process of irradiating UV rays and the like, is not necessary until printing of the same color is completed.
In the operation of the second printing IF of the first ink portion, when the printing moves L+Δ+ε in the first direction and rotates about the z-axis a predetermined angle θ and 90°, or the pattern of the transfer plate is rotated in the opposite direction to the first printing, the printing of the second ink starts at the same angle, and the first printing I2 of the second ink portion is performed, and thus the printing time is reduced. Similar to the first ink portion, the printing material moves L+Δ+ε in the first direction and rotates about a z-axis a predetermined angle θ and 90°, and the second printing I2′ of the second ink portion is performed. Hereinafter, multi-color printing and drying are simultaneously performed on a front surface of the stereoscopic surface while the roll makes one rotation.
Since the printing method is achieved by one rotation of the roll, as long as an error of degree of horizontality in a roll movement direction (the first direction) of a linear slider or an error of control software does not occur, the printing can be performed with high precision and high reproducibility.
According to the present invention, gravure offset printing can be performed on various shapes of printing materials in one printing cycle. Particularly, the gravure offset printing can be performed even on a cylindrical printing material and a three-dimensional stereoscopic printing material with thickness and having a curved surface.
Further, according to the present invention, various colors of inks can be printed at the same position on each printing material to overlap each other, and thus a required color obtained by combining colors of the inks can be printed in one printing cycle.
Further, according to the present invention, since mass printing can be performed on a plurality of printing materials in one printing cycle, a printing speed can be increased, and thus, economic feasibility can be increased.
Filing Document | Filing Date | Country | Kind |
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PCT/KR2017/004527 | 4/27/2017 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
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WO2017/188767 | 11/2/2017 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
5335595 | Yamashita | Aug 1994 | A |
6276266 | Dietz | Aug 2001 | B1 |
20040123753 | Yoo | Jul 2004 | A1 |
20070214977 | Okamoto | Sep 2007 | A1 |
20120292307 | Kim | Nov 2012 | A1 |
20150352829 | Sente | Dec 2015 | A1 |
20170050426 | St. Pierre | Feb 2017 | A1 |
Number | Date | Country |
---|---|---|
05-169626 | Jul 1993 | JP |
H09-277491 | Oct 1997 | JP |
3731937 | Jan 2006 | JP |
2008-168578 | Jul 2008 | JP |
2014-033013 | Feb 2014 | JP |
5493908 | May 2014 | JP |
10-2016-0007122 | Jan 2016 | KR |
Entry |
---|
International Search Report issued in PCT/KR2017/004527; dated Aug. 18, 2017. |
Number | Date | Country | |
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20190152213 A1 | May 2019 | US |