JP2017132052A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photogravure off-set printer including a trackable flexible blanket corresponding to the shape of a body to be printed to which a three-dimensional processing such as a curved surface is applied.SOLUTION: In an off-set printer including a blanket rotating in a prescribed direction, a blanket trunk for holding the blanket, and a stage for holding a body to be printed, a material of the blanket is silicone rubber, and hardness of the silicone rubber is 5° or higher and 30° or lower.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a printing apparatus and a blanket that perform printing on a three-dimensional object by an offset method.

  In gravure offset printing, the pattern engraved on the plate can be reproduced more faithfully than printing methods such as screen printing and inkjet, and fewer steps are required compared to photolithography methods. It has been studied so far for printing display panel wiring and touch panel signal wiring.

  In particular, gravure offset printing is capable of fine printing comparable to the photolithography method, and has a higher degree of freedom in substrate selection than the photolithography method.

  In recent years, in the field of wearables and the like, there is a movement to arrange wiring on a curved substrate such as a bent substrate.

  When considering wiring to such a curved surface using printing, any method of printing on a base material processed into a curved surface shape or the like, processing the base material after printing, and conforming to the curved surface Is required.

  However, unlike metal wiring, the conductive ink used in printed electronics is susceptible to bending when cured, and breaks when the substrate is processed after printing and curing. Therefore, it is difficult to process the printed material into a three-dimensional object, and there is a demand for direct printing on a three-dimensional object.

  In order to make this possible, it is required to realize printing on a base material that has been three-dimensionally processed, such as a curved surface.

  In conventional gravure offset printing, printing is performed by holding a substrate on a flat stage or an impression cylinder and bringing a blanket onto which ink has been transferred from a plate into contact while rotating.

  Currently, an inkjet method is often taken up as a printing method for curved surfaces. However, the ink used in the ink jet method has a low viscosity, and the printed droplets are distorted. Unless a special substrate is used, it is more difficult to print fine lines than the gravure offset method.

  As a conventional technique for printing on a curved surface, there is a method in which a plate ink is transferred to a curved surface pad and printed on a subject (for example, see Patent Document 1).

  However, in this printing method, it is necessary to appropriately change the shape of the pad (blanket) used for transfer depending on the shape of the subject. In addition, the follow-up to the curved surface of the subject and the finish of printing are largely due to the elasticity of the pad, which makes it difficult to control.

JP-A-60-157864

  The present invention has been made in view of such problems, and an object of the present invention is to provide an offset printing apparatus and a blanket that enable printing on a printing medium having a curved shape.

One aspect of the present invention for solving the above problems is a blanket that rotates in a predetermined direction, a blanket cylinder that holds the blanket, a stage that holds the printing medium, and the blanket rotates and moves on the surface thereof. The blanket is made of silicone rubber, and the offset hardness of the silicone rubber is 5 ° to 30 °.
Another aspect of the present invention is a blanket formed of silicone rubber that is provided on the outer periphery of a blanket cylinder having a cylindrical shape and has a hardness of 5 ° to 30 °.

  ADVANTAGE OF THE INVENTION According to this invention, the offset printing apparatus and blanket which enable the printing to the to-be-printed body with a curved surface shape can be provided.

It is a cutting part end elevation showing an outline of a retransfer process of ink from a blanket to a curved substrate according to an embodiment of the present invention. It is a cutting part end view in the blanket cylinder axis direction which shows the outline of the blanket concerning one embodiment of the present invention. It is a cutting part end view which shows the outline | summary of the ink filling (doctoring) process which concerns on one Embodiment of this invention. It is a cutting part end view showing the outline of the transfer process of the ink to the blanket concerning one embodiment of the present invention. It is a cutting part end elevation showing an outline of a retransfer process of ink from a blanket to a curved substrate according to an embodiment of the present invention. It is a cutting part end elevation showing an outline of a retransfer process of ink from a blanket to a curved substrate according to an embodiment of the present invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[Embodiment 1]
FIG. 1 is an end view of a cut portion showing an outline of a retransfer process of ink from a blanket to a curved substrate according to the present embodiment.
Although details of the blanket 4 will be described below, the blanket 4 is provided on the outer periphery of a blanket cylinder 6 having a cylindrical shape. Further, a hollow 16 part is provided between the blanket 4 and the blanket cylinder 6. FIG. 1 shows a state in which the ink 18 (not shown) transferred to the blanket 4 has started to be transferred to the substrate 8 having a curved surface shape arranged on the stage 12. When the blanket 4 rotates and moves in a predetermined direction and comes into contact with the substrate 8, the blanket 4 deforms following the shape of the substrate. Thereby, it is possible to print on the printing medium 8 having a curved surface shape.

  The shape of the blanket cylinder 6 is a cylindrical shape. A cavity 16 is provided between the blanket cylinder 6 and the blanket 4 on the outer periphery of the blanket cylinder 6 except for a portion for fixing the blanket cylinder 6 and the blanket 4. The blanket 4 does not come into contact with the blanket cylinder 6 except for portions fixed to the blanket cylinder 6 (for example, both ends of the blanket 4 formed into a cylindrical shape).

  The blanket according to the present embodiment will be further described with reference to FIG.

FIG. 2 is an end view of the cut portion of the blanket cylinder 6 connected to the blanket cylinder 6 and the blanket cylinder 6 according to the present embodiment.
The blanket 4 is formed in a cylindrical shape, and the blanket cylinder 3 is not touched except for a portion fixed to the blanket cylinder 6, and a cavity 16 is provided between the blanket cylinder 6 and the blanket 4. The blanket 4 is cylindrical in this example, but the shape is not limited to this, and a blanket bag used for tampo printing, for example, may be used.

  In the first embodiment, many blanks 14 are provided in the blanket cylinder 6. The cavity 16 is filled with fluid through a hole 14 provided in the blanket cylinder 6. Although not shown, a device for supplying fluid and a device for measuring the pressure in the cavity 16 through the fluid may be further provided. By filling the cavity 16 with fluid and applying pressure, the shape of the blanket 4 and the printing pressure when transferring ink from the blanket 4 to the printing medium 8 are controlled.

  Although not shown, the printing apparatus of the present invention may be provided with a mechanism for controlling the temperature of the fluid to be introduced. For example, as printing continues, the blanket 4 may swell with the solvent component of the ink 18, and the printed line may become thicker, or the solvent component may not be absorbed and the ink 18 may not be removed from the plate 10. In this case, a method of warming the inside of the blanket 4 by heating the fluid in the cavity and evaporating the solvent. Alternatively, this can be prevented by a method of increasing the temperature of the ink 18 to promote the diffusion of the solvent inside the ink 18. On the other hand, the cooling mechanism can cool the blanket 4 heated by the heating mechanism and adjust the surface of the blanket 4 to an appropriate temperature.

  The means for introducing the fluid filling the cavity 16 need not be limited to holes, but may be a needle-like nozzle. Further, the number of introducing means is not limited, and the blanket cylinder 6 may be provided innumerably or only at one place. It can be appropriately selected according to the shape of the blanket 4. Further, the fluid filling the cavity 16 can be selected from gas and liquid depending on the application. Further, there is no particular limitation as long as it does not change the physical properties of the blanket 4. For example, by selecting a liquid as the fluid, the load capacity during printing of the blanket 4 can be increased. When the gas is selected, the temperature inside the cavity 16 can be easily controlled, and the temperature control of the blanket 4 is facilitated.

[Printing method]
FIG. 3 is a cut end view showing an outline of a printing process called doctoring.

In the plate 10, a predetermined pattern to be printed by the user is expressed by a depression. The method for forming the depression and the material and shape of the plate are not particularly limited, and may be prepared by wet etching or dry etching such as ion beam. The shape of the plate 10 does not need to be flat, and may be cylindrical, and the material may be glass, metal, resin, or the like.
In this step, first, the ink 18 is supplied onto the surface of the plate 6. The supply position of the ink 18 is not particularly limited, but it is preferable to supply the ink 18 near the doctor 2. By supplying the ink in this way, it is possible to fill the pattern of the plate 10 with a predetermined amount of ink by the movement of the doctor 2. The shape of the doctor 2 may be a known shape.

Next, the doctor 2 is moved on the surface of the plate 10 along the surface of the plate 10 in the direction of the right arrow in FIG. 3 to scrape the ink 18 placed on the surface of the plate 10. The operation of filling is performed. This is a process called doctoring.
The doctor 2 has a straight end. The doctor 2 has a role of supplying the ink 18 to the pattern portion of the plate 10 and scraping off the ink 18 outside the pattern of the plate 10 (referred to as a non-image portion).

  Moreover, although not shown in figure, you may further provide the coat doctor which spreads the ink 18 which remained behind the plate 6 after doctoring on the plate surface. In particular, when ink that is easily dried is used, it is desirable to cover the plate surface with ink 18 except when necessary in order to prevent drying of the ink 18 filled in the pattern by doctoring. Of course, the coating doctor may be omitted as long as it has a mechanism that can cover the entire plate with ink immediately after the printing operation, such as a dispenser or an inkjet.

FIG. 4 is an end view of a cut portion showing an outline of a process of transferring the ink 18 filled in the plate 10 to the blanket 4.
The ink 18 is transferred to the blanket 4 by the blanket 4 rolling on the plate 10. At this time, by controlling the fluid pressure in the cavity 16 inside the blanket 4, it is possible to transfer ink as usual without causing the blanket 4 to be deformed.
Examples of the material of the blanket 4 include nitrile bradiene rubber and silicone rubber. In the present embodiment, silicone rubber is used. Since the silicone rubber has a low surface energy, the ink separation is good when the ink 18 transferred from the plate 6 is retransferred to the substrate.

After the ink 18 is transferred from the plate 10 to the blanket 4, it is preferable that the ink solvent component is appropriately absorbed on the blanket 4 to increase the cohesive force and then transferred to the printing medium 8. At this time, it is more preferable to control the temperature of the blanket 4 or the ink 18. Thereby, it is possible to heat the blanket 4 or the ink 18 to promote the absorption of the ink solvent component, or to cool the oppositely heated blanket 4 to adjust the surface of the blanket 4 to an appropriate temperature. .
Therefore, it is possible to maintain optimum printing conditions that were impossible with the conventional method.

  The silicone rubber of the blanket 4 may be adjusted in hardness by changing the ratio of crosslinking or the like, or by appropriately mixing silicone oil or silicone gel.

  Moreover, the hardness of the silicone rubber used for the blanket 4 is preferably 5 ° or more and 30 ° or less by the measurement method shown in JIS K 6253-2012. Within this range, the blanket 4 alone can change following the curved surface shape of the substrate 8, and printing on a substrate having a curved surface is possible. Further, by combining with the fluid pressure control of the cavity 16 in the blanket 4, it is possible to print on the substrate 8 having a more complicated curved shape by appropriately deforming the blanket 4 following the substrate during printing. Become.

  Next, the process of retransferring the ink 18 transferred to the blanket 4 to the curved substrate 8 will be described with reference to FIGS. FIGS. 5 and 6 are cut end view showing an outline of the retransfer process of the ink from the blanket 4 to the curved substrate.

  FIG. 5 is a diagram when the transfer of the ink 18 (not shown) transferred to the blanket 4 to the printing medium 8 having a curved surface shape is started. The cavity 16 is filled with fluid through the holes 14, and is connected to a device for supplying fluid and a device for measuring the pressure in the cavity 16 through the fluid (not shown). When the blanket 4 comes into contact with the substrate 8, the cavity 16 discharges fluid through the holes 14. Thus, by reducing the pressure in the cavity 10, the shape of the blanket 4 can follow the curved surface of the substrate 8 and deform. Thereby, the ink 10 can be transferred to the non-printed body 8 having a curved surface shape. When the blanket 4 is merely wound around the conventional blanket cylinder 6, it cannot be deformed / followed by a curved surface shape such as the substrate 8. Therefore, it is difficult to transfer the ink 18 to the printing medium 8. On the other hand, the printing apparatus of the present invention can be deformed by controlling the pressure of the cavity of the blanket 4. Therefore, it can be deformed in accordance with the curved surface of the printing medium 8 during printing, and printing on the printing medium 8 having a curved surface shape becomes possible. A plurality of devices for measuring the pressure may be provided on the blanket 4. By providing a plurality of devices for measuring pressure, the pressure of the blanket 4 can be locally controlled. Therefore, the shape of the blanket 4 can be more selectively deformed with respect to the printing medium 8 having a curved surface shape. The fluid injected into the cavity 16 through the holes 14 may be changed for each hole 14. By changing the fluid injected into the cavity 16 for each hole 14, the printing conditions can be determined in more detail.

  The blanket 4 reaches the printing medium 8 and starts transferring ink to the printing medium 8 while being deformed. Thereafter, the shaft of the blanket cylinder 6 is slightly raised and rotated and moved toward the printing body 8, whereby the ink transfer proceeds so that the blanket 4 runs up the surface of the printing body 8.

  FIG. 6 shows the latter half of the process of transferring the ink from the blanket 4. As in the first half, the ink 18 can be transferred along the substrate 8 by deformation of the blanket 4.

  Further, the stage 12 may be provided with a mechanism capable of translation, rotation, ascending and descending, and these operations may be appropriately performed according to the movement of the blanket 4. As a result, for example, printing can be performed while correcting distortion of the printing pattern caused by the deformation of the blanket 4.

  The printing apparatus of the present invention can take the same steps as conventional gravure offset printing without providing a cavity by controlling the pressure in the blanket 4. In conventional gravure offset printing, fine lines, which are not good at pad printing, have already been printed, and how to transfer them to a substrate other than a flat shape has been a problem. As described above (paragraph [0035]), the printing apparatus of the present invention has solved this problem.

  As described above, the flexibility of the blanket 4 can be freely controlled by providing a cavity in the blanket 4 and controlling the pressure. As a result, the blanket 4 is deformed following the shape of the substrate 8 to be printed, and the printing finish on the substrate 8 having a curved surface shape can be achieved. Therefore, according to the present invention, printing can be performed even on a three-dimensional object having a curved surface shape.

  The present invention is useful for a gravure offset printing apparatus, a printing apparatus for a three-dimensional object, and the like.

2 Doctor 4 Blanket 6 Blanket cylinder 8 Printed body 10 Plate 12 Stage 14 Hole 16 Cavity
18 ink

Claims (7)

A blanket rotating in a predetermined direction;
A blanket cylinder holding the blanket;
A stage for holding the substrate to be printed and the blanket rotating and moving on the surface thereof;
The offset printing apparatus, wherein the blanket material is silicone rubber, and the silicone rubber has a hardness of 5 ° to 30 °.   The offset printing apparatus according to claim 1, wherein an inside of the blanket is hollow except for a portion connected to the blanket cylinder.   The offset printing apparatus according to claim 1, further comprising a mechanism for introducing a fluid into a cavity inside the blanket.   The offset printing apparatus according to claim 3, further comprising a temperature adjustment mechanism.   The offset printing apparatus according to claim 1, further comprising a mechanism that allows the stage to freely move in accordance with the movement of the blanket during printing. Provided on the outer periphery of a blanket cylinder having a cylindrical shape,
A blanket formed of silicone rubber having a hardness of 5 ° to 30 °.   The blanket according to claim 7, wherein an outer periphery of the blanket cylinder and an inside of the blanket are hollow except for a portion connected to the blanket cylinder.