JP2009119709A - Printer, and printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printer which can efficiently remove an ink solvent impregnated and stored into a blanket by repetition of printing treatment, and can suppress the defect in the transfer of ink and deterioration in dimensional precision in a pattern upon continuous printing, and a printing method. <P>SOLUTION: A solvent absorption sheet (solvent absorber) 6 is brought into contact with the outer circumferential face of the blanket 2, also a pair of tension rollers (holding members) 7, 8 are oppositely arranged at the outer circumference of the blanket 2 at intervals, and the solvent absorption sheet (solvent absorber) 6 is held to a tension state. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a printing apparatus and a printing method, and more particularly to a printing apparatus and a printing method suitable for high-precision printing such as offset printing and reverse printing.

  In recent years, patterns such as color filter layers of liquid crystal color filters and patterns such as silver electrodes on the electrode substrate of a plasma display panel (PDP) are printed by printing in order to meet the demand for larger screens and lower costs of display devices. It has been proposed to form. Further, since these patterns are fine patterns and excellent printing accuracy is required, application of intaglio offset printing using a silicone blanket is being studied.

However, since the electrode substrate of the liquid crystal color filter or PDP is a substrate that does not absorb an ink solvent such as glass, the ink solvent penetrates and accumulates in the blanket by repeating the printing process, and the blanket swells. For this reason, defects such as defective transfer of ink and a decrease in dimensional accuracy of the pattern occur, resulting in an increase in defective products.
On the other hand, as a technique for removing the ink solvent that has penetrated and accumulated in the blanket from the blanket, Patent Document 1 proposes a solvent absorption mechanism that rotationally contacts the blanket and the solvent absorber. A mechanism has been proposed in which a moisture absorbing sheet is pressed against the blanket to adjust the wet state of the blanket with the ink solvent. Further, in Patent Document 3, a solvent absorber is formed in a tape shape wound around a roller, and this solvent absorber is sequentially fed out and brought into contact with a part of the blanket blanket (transfer body roller). Describes an apparatus for transferring an ink solvent from a silicone rubber layer to a solvent absorber (see FIG. 3). Patent Document 4 discloses a solvent absorber formed in an endless belt shape or a roll shape on the surface of a blanket. And a printing apparatus that absorbs the ink solvent from the rubber layer on the surface of the blanket (see FIG. 1).
JP 2000-158633 A JP 2000-158620 A JP-A-8-156388 JP 2006-035769 A

However, in the mechanisms described in Patent Documents 1 and 2, the contact area between the blanket and the solvent absorber (moisture absorbing sheet) is small, and the efficiency of sucking the solvent from the blanket is low. For this reason, it takes time to remove the solvent from the blanket, and printing productivity is reduced.
Further, in the apparatus shown in FIG. 3 of Patent Document 3 and the printing apparatus shown in FIG. 1 of Patent Document 4, although the contact area between the blanket and the solvent absorber is wide, Since the body roller 4) and the solvent absorber in contact with the body roller are so called, the efficiency of sucking the solvent from the blanket is still low.

  An object of the present invention is to efficiently remove the ink solvent that has penetrated and accumulated in the blanket by repeating the printing process, and to suppress an ink transfer failure and a decrease in pattern dimensional accuracy during continuous printing and And a printing method.

  In order to achieve the above object, a printing apparatus according to the present invention includes a blanket for supporting ink transferred to a printing medium on a surface, a blanket cylinder for fixing the blanket to the surface, and an outer peripheral surface of the blanket. And a pair of holding members for holding the solvent absorber, and soaks in the blanket. In the solvent removal process of sucking and removing the ink solvent, the solvent absorber is in contact with the outer peripheral surface of the blanket, and the pair of holding members are spaced apart from each other in the circumferential direction of the blanket. Opposed to the outer peripheral surface of the blanket, the solvent absorber is held in a tension state.

  In the printing apparatus, the solvent absorber contacts the outer peripheral surface of the blanket during the solvent removal process of sucking and removing the solvent of the ink that has permeated into the blanket. Furthermore, a pair of holding members are disposed opposite to the outer peripheral surface of the blanket at a distance from each other in the circumferential direction of the blanket to hold the solvent absorber in a tensioned state. Thus, the solvent absorber contacts the outer peripheral surface of the blanket in a wide area in the circumferential direction, and is pressed in the inner direction of the blanket to be in close contact with the outer peripheral surface of the blanket.

Therefore, according to the printing apparatus, it is possible to efficiently absorb and remove the ink solvent that has penetrated and accumulated in the blanket during the solvent removal process. In addition, this makes it possible to suppress ink transfer failure and decrease in pattern dimensional accuracy during continuous printing while maintaining printing productivity.
In the printing apparatus of the present invention, it is preferable that the solvent absorber is in contact with at least the entire blanket printing region in the blanket during the solvent removal treatment. In this case, the removal efficiency of the ink solvent which has penetrated and accumulated in the blanket can be further improved.

  In addition, a printing method of the present invention for achieving the above object includes a blanket for supporting ink transferred to a printing medium on a surface, a blanket cylinder for fixing the blanket to the surface, and a blanket of the blanket. A printing method using a printing apparatus comprising: a solvent absorber for sucking out the solvent of ink that has permeated into the blanket by contact with an outer peripheral surface; and a pair of holding members for holding the solvent absorber. The ink carrying process for carrying ink on the surface of the blanket, the printing process for printing the ink carried on the surface of the blanket on the printing medium, and the solvent of the ink that has permeated into the blanket is absorbed and removed. A solvent removal step, and in the solvent removal step, the solvent absorber is brought into contact with the outer peripheral surface of the blanket, One, the pair of holding members, face disposed on the outer circumferential surface of the blanket spaced from one another in the circumferential direction of the blanket, is characterized by holding the solvent absorber in tension.

  In the printing method described above, the solvent absorber is brought into contact with the outer peripheral surface of the blanket in the solvent removing step of sucking and removing the solvent of the ink soaking into the blanket. Further, the pair of holding members are disposed opposite to the outer peripheral surface of the blanket at a distance from each other in the circumferential direction of the blanket to hold the solvent absorber in a tensioned state. Thus, the solvent absorber contacts the outer peripheral surface of the blanket in a wide area in the circumferential direction, and is pressed in the inner direction of the blanket to be in close contact with the outer peripheral surface of the blanket.

Therefore, according to the printing method, the ink solvent that has penetrated and accumulated in the blanket can be efficiently sucked and removed in the solvent removal step. In addition, this makes it possible to suppress ink transfer failure and decrease in pattern dimensional accuracy during continuous printing while maintaining printing productivity.
In the printing method of the present invention, it is preferable that, in the solvent removal step, the solvent absorber is brought into contact with at least the entire blanket printing region of the outer peripheral surface of the blanket. In this case, the removal efficiency of the ink solvent which has penetrated and accumulated in the blanket can be further improved.

  According to the printing apparatus and the printing method of the present invention, the ink solvent that has penetrated and accumulated in the blanket can be efficiently removed, the productivity of printing due to the swelling of the blanket, the occurrence of poor ink transfer, and Problems such as a decrease in the dimensional accuracy of the print pattern can be suppressed. Such a printing apparatus and printing method of the present invention are suitable for high-precision printing such as offset printing and reversal printing, and particularly for printing formation of a color filter layer of a liquid crystal color filter and a silver electrode of a PDP.

FIG. 1 is a schematic explanatory view showing an embodiment of a printing apparatus of the present invention. FIGS. 2A to 2C are cross-sectional views showing an example of a solvent absorber, and FIG. ) To FIG. 3C are explanatory views showing the lapping operation of the solvent absorber. Hereinafter, an embodiment of a printing apparatus and a printing method of the present invention will be described in detail with reference to these drawings.
Referring to FIG. 1, a printing apparatus 1 includes a blanket 2, a blanket cylinder 3 that fixes the blanket 2 to the surface, an intaglio plate 4 as a printing plate, and a substrate 5 as a printing medium. Yes.

The printing method using the printing apparatus 1 includes an ink carrying process for carrying ink on the surface of the blanket 2 and a printing process for printing the ink carried on the surface of the blanket 2 on the substrate 5.
The blanket 2 includes a support film layer and a surface print layer that covers the outer periphery of the support film layer.

  For the surface printing layer, for example, silicone rubber, acrylonitrile-butadiene rubber (NBR), ethylene-propylene-diene copolymer rubber (EPDM), or the like is used. Among them, for example, silicone rubber is preferably used for high-precision printing, and more preferably, silicone rubber having a Shore A hardness of 20 to 70 is used. The thickness of the surface printing layer is, for example, 50 to 5000 μm, preferably 100 to 2000 μm, and the surface roughness is arithmetic average roughness Ra, for example, 0.001 to 1 μm, preferably 0.01 to 0. .5 μm.

For the support film layer, for example, a resin film such as a polyester film is used. The thickness of a support film layer is 20-1000 micrometers, for example, Preferably, it is 50-500 micrometers.
The total thickness of the surface printing layer and the support film layer of the blanket 2 is, for example, 100 to 6000 μm, or preferably 200 to 2500 μm.

The blanket 2 is wound around the surface of a cylindrical blanket cylinder 3 and has a cylindrical shape that can rotate together with the blanket cylinder 3.
For the blanket cylinder 3, for example, a metal cylinder or the like is used. The blanket cylinder 3 is held so that it can rotate and move in a direction perpendicular to the axial direction of the blanket cylinder 3. Specifically, the outer peripheral surface of the blanket 2 fixed to the surface is in contact with an intaglio 4 and the substrate 5 described later, and is held so as to be able to roll on the intaglio 4 and the substrate 5. Further, the blanket cylinder 3 is in a direction orthogonal to the axial direction so that the outer peripheral surface of the blanket 2 and the solvent absorbing sheet 6 can come into contact with each other by relative movement between a pair of tension rollers 7 and 8 described later. The translation can be done freely.

The outer diameter of the blanket 2 in a state of being wound around the blanket cylinder 3 is appropriately selected depending on the area of the printing region. In the blanket 2, a region excluding a portion inserted into the groove portion of the blanket cylinder 3 and the vicinity of the groove portion in the circumferential direction can be set as a printing region.
Further, the blanket may have a cylindrical shape having, for example, a cylindrical sleeve and a surface printing layer formed on the outer peripheral surface of the cylindrical sleeve. In this case, the blanket is used by fitting and fixing the inner peripheral surface of the cylindrical sleeve to the outer peripheral surface of the blanket cylinder. In this case, an arbitrary region corresponding to the size of the printing medium is selected from the outer peripheral surface of the blanket as the printing region in the circumferential direction of the blanket.

In the ink carrying process of the printing method, the blanket 2 is brought into contact with the intaglio 4 and is rolled on the intaglio 4 to transfer the ink (not shown) filled in the recesses of the intaglio 4 to the outer peripheral surface of the blanket 2. . Thereby, an ink pattern corresponding to the print pattern printed on the substrate 5 is formed on the outer peripheral surface of the blanket 2.
The intaglio 4 has a recess corresponding to a print pattern printed on the substrate 5. For the intaglio 4, for example, a glass plate such as soda lime glass, for example, a metal (amber material) plate or the like is used. Further, the printing plate is not limited to the illustrated intaglio plate 4, and various printing plates such as a relief plate and a lithographic plate can be used.

The board | substrate 5 is not specifically limited, According to the objective and use of printing, it selects suitably.
The ink is not particularly limited, and various inks are used according to the purpose and application of printing. For example, liquid crystal color filter color filter layer and black matrix formation include resin, solvent, pigment, and if necessary, pigment dispersant, extender pigment, curing catalyst, leveling agent (surface tension modifier), etc. An ink having a boiling point of 70 to 200 ° C. and a swelling ratio of the surface printing layer of 5 to 100% when the surface printing layer of the blanket 2 is immersed in the ink at 23 ° C. for 24 hours is preferably used. It is done.

  In such an ink, for example, polyester-melamine resin, epoxy-melamine resin, acrylic resin, or the like is used as the resin. The weight average molecular weight of the resin is appropriately selected according to physical properties such as ink viscosity and thixotropy, but is preferably a standard polystyrene equivalent value by GPC method, preferably 1000 to 20000, and more preferably 5000. ~ 15000.

The solvent preferably has a boiling point of 70 to 200 ° C. Specifically, examples of the solvent having a boiling point of 70 to 200 ° C. include alcohols (more preferably, higher alcohol), glycols, glycol esters, alkyl ethers, aliphatic hydrocarbons, and alicyclic hydrocarbons. , Aromatic hydrocarbons, carboxylic acid esters and the like are used.
In the case of forming a color filter layer of a liquid crystal color filter, for example, an anthraquinone red pigment, a halogenated phthalocyanine green pigment, a phthalocyanine blue pigment, or the like is used, and further, a yellow pigment or a violet pigment is used. Used as an auxiliary pigment. When forming a black matrix of a liquid crystal color filter, for example, carbon black, iron oxide (iron black), titanium black, iron sulfate, an alloy such as Fe—Co—Mo, or the like is used. The average primary particle diameter of the pigment is preferably 1 to 100 nm.

The swelling ratio is an index related to the absorption rate of the ink solvent in the surface printing layer of the blanket 2 and the degree of ink repelling. The swelling ratio is preferably 10 to 50%, and more preferably 10 to 30%, within the above range.
The ink described above is prepared, for example, by blending the above resin, solvent, pigment, and the like, and mixing and stirring with various mixers, kneaders, mills, and the like.

  Further, a so-called reverse printing method may be employed for the ink carrying step. In this case, for example, the ink is applied to the entire printing region of the outer peripheral surface of the blanket 2, and then the blanket 2 is rolled on the concave / convex plate as a printing plate, thereby contacting the convex portion of the concave / convex plate. The ink in the portion thus formed is transferred to the convex portion and removed from the outer peripheral surface of the blanket 2. Further, in this case, the convex portion of the concavo-convex plate is formed as a reversal pattern that is reversed to the print pattern printed on the substrate 5. On the other hand, an ink pattern corresponding to the print pattern printed on the substrate 5 is formed on the outer peripheral surface of the blanket 2.

In the printing process of the printing method, the ink pattern is transferred onto the surface of the substrate 5 by rolling the blanket 2 onto which the ink pattern has been transferred from the intaglio 4 while being in contact with the substrate 5. . Thereby, an ink pattern corresponding to the print pattern is printed on the substrate 5.
The printing apparatus 1 further includes a solvent absorbing sheet 6 as a solvent absorber that absorbs the solvent of ink that has oozed into the blanket 2 by contact with the outer peripheral surface of the blanket 2, and a solvent removal process (solvent removal step) described later. A pair of tension rollers 7 and 8 as holding members for holding the solvent absorbent sheet 6 in tension, and a pair of cranks for moving the tension rollers 7 and 8 to a predetermined position during the lapping operation of the solvent absorbent sheet 6 9 and 10 and a pair of arms 11 and 12.

In addition, the printing method using the printing apparatus 1 further includes a solvent removal step of sucking the solvent of the ink soaking into the blanket 2 with the solvent absorbing sheet 6 and removing it from the blanket 2.
The solvent absorbing sheet 6 is a long member provided with a solvent absorbing layer on at least the surface in contact with the outer peripheral surface of the blanket. Examples of the layer configuration of the solvent absorbing sheet 6 include the following.
A laminate composed of the solvent absorption layer 13 and the base material 14 for fixing the solvent absorption layer 13 (see FIG. 2A).
A laminate in which the solvent absorption layer 13, the base material 14, and the elastic layer 15 are laminated in this order (see FIG. 2B).
A laminated body in which the solvent absorbing layer 13, the elastic layer 15, and the base material 14 are laminated in this order (see FIG. 2C).
Although the layer structure of the solvent absorbent sheet 6 is not particularly limited, for example, a laminate having a two-layer structure shown in FIG. 2A is preferable because the structure is simple. In addition, for example, a three-layer laminate including the elastic layer 15 as shown in FIG. 2B or FIG. 2C is adapted to the type of ink solvent, the material for forming the surface printing layer of the blanket 2, and the like. Can be employed as appropriate.

  The solvent absorbing layer 13 is in contact with the outer peripheral surface of the blanket 2 and absorbs the ink solvent from the surface printing layer of the blanket 2. For the solvent absorbing layer 13, for example, silicone rubber, urethane resin, urethane elastomer, natural rubber, NBR, butadiene rubber (BR), EPDM, or the like is used. These can be appropriately selected from the viewpoint of the affinity of the ink for the solvent, and among them, urethane resin is preferably used.

  The surface roughness of the solvent absorption layer 13 is not limited to this, but from the viewpoint of preventing the adhesion of dirt to the outer peripheral surface of the blanket 2, the arithmetic average roughness Ra is, for example, 1 μm or less, preferably 0 .1 to 0.8 μm. Further, the thickness of the solvent absorbing layer 13 is not particularly limited, and prevents distortion when it is brought into contact with the outer peripheral surface of the blanket 2 and held in a tension state by a pair of tension rollers (holding members) 7 and 8; From the viewpoint of securing the ink solvent absorption capacity by the solvent absorption layer 13, it is, for example, 100 to 2000 μm, and preferably 300 to 1500 μm.

  For the base material 14, for example, a resin film made of polyester (particularly, PET or the like), an imide resin, an acrylic resin, or the like is used. The thickness of the base material 14 is, for example, 50 to 500 μm, preferably 60 to 250 μm, from the viewpoints of handling properties, mechanical strength, flexibility, and the like of the solvent absorbent sheet 6. Although the surface roughness of the base material 14 is not limited to this, from the viewpoint of ensuring the smoothness of the solvent absorbing layer 13, the arithmetic average roughness Ra is, for example, 30 to 2000 nm, preferably 50 to 1000 nm. The mechanical strength of the substrate 14 is, for example, 70 to 500 MPa, preferably 100 to 500 MPa, as the tensile elastic modulus at 0.2% elongation.

  For the elastic layer 15, for example, solid rubber, foamed rubber, soft resin, or the like is used, and preferably, soft urethane resin or the like is used. The thickness of the elastic layer 15 is 0.1-5 mm, for example, Preferably, it is 0.2-2 mm. The mechanical strength of the elastic layer 15 is, for example, 0.5 to 20 MPa, preferably 1.0 to 10 MPa as a compression elastic modulus at 1% compression.

In addition, although the total thickness of the solvent absorption sheet 6 is not limited to this, Preferably, it is 200-1000 micrometers.
The tension rollers 7 and 8 are moved to predetermined positions by the rotational movement of the cranks 9 and 10 and the accompanying movement of the arm 17 and the rotational movement about the fulcrums 16 and 17 of the cranks 9 and 10. . Thereby, the lapping operation | movement which the solvent absorption sheet 6 coat | covers the outer peripheral surface of the blanket 2 is performed (refer Fig.3 (a)-FIG.3 (c)).

In the ink carrying process and the printing process described above, the pair of tension rollers 7 and 8 come into contact with the solvent absorbing sheet 6 from the surface opposite to the contact surface with the outer peripheral surface of the blanket 2 of the solvent absorbing sheet 6. (See FIG. 3 (a)). In this state, the pair of tension rollers 7 and 8 hold the solvent absorbing sheet 6 so as not to contact the outer peripheral surface of the blanket 2.
On the other hand, in the solvent removal process, that is, in the solvent removal process by the solvent absorbing sheet 6, first, the cranks 9 and 10 are rotated in the opposite directions (reversely), and the arms 11 and 12 are moved in the vertical direction. Move down. By the movement of the pair of arms 11 and 12, the pair of tension rollers 7 and 8 are moved downward in the vertical direction, and the solvent absorbing sheet 6 is brought into contact with the outer peripheral surface of the blanket 2 (see FIG. 3B).

  Next, the cranks 9 and 10 rotate in opposite directions (reversely) around the fulcrums 16 and 17 with the pair of joints 18 and 19 connecting the arms 11 and 12 fixed respectively. To do. Thereby, the solvent absorption sheet 6 contacts the entire printing area of the blanket 2, and the pair of tension rollers 7 and 8 holds the solvent absorption sheet 6 in a tension state.

It can be controlled by a pair of cranks 9 and 10, a pair of joints 18 and 19 connecting the cranks 9 and 10 and the arms 11 and 12, and a servo mechanism.
Moreover, the lapping operation | movement of the solvent absorption sheet 6 is not limited to a series of operation | movement shown to Fig.3 (a)-FIG.3 (c). For example, after a pair of tension rollers 7 and 8 are adjacent to each other and brought into contact with the outer peripheral surface of the blanket 2 via the solvent absorbing sheet 6, the tension rollers 7 and 8 are arranged along the outer peripheral surface of the blanket 2. They may be moved in opposite directions in the circumferential direction. In this case, the adhesion between the solvent absorbent sheet 6 and the outer peripheral surface of the blanket 2 can be further enhanced.

  For example, the solvent removal process may be performed every time a series of printing processes including an ink carrying process and a printing process are performed once, or may be performed every time the above series of printing processes are performed a plurality of times. The frequency of the solvent removal step may be set as appropriate depending on the extent to which the ink solvent has permeated into the blanket 2. The degree to which the ink solvent is soaked into the blanket 2 is, for example, an imaging means (not shown) that represents the shape of the ink pattern printed on the substrate 5 (for example, a planar or three-dimensional shape such as a size, thickness, cross-sectional shape). It can be measured by an image analysis means (for example, a CCD camera or the like) and can be judged based on a change with time of the ink pattern shape.

  Further, when the pair of tension rollers 7 and 8 are in contact with the outer peripheral surface of the blanket 2 and hold the blanket 2 in a tensioned state (see FIG. 3C), the tension applied to the blanket 2 and the blanket The contact time between the ink absorbing sheet 2 and the solvent absorbing sheet 6 may be set as appropriate depending on the extent to which the ink * solvent has permeated into the blanket 2 and the ease with which the ink solvent is absorbed from the blanket 2.

  For example, when a color filter layer of a liquid crystal color filter is printed using a silicone blanket and an ink having a glycol ester having a relatively high boiling point (about 200 to 280 ° C.) as a solvent, it is printed. In view of the fact that the ink pattern is fine and extremely high printing accuracy is required, the solvent removal step is performed, for example, every time the above-described series of printing processes are performed 1 to 10 times, preferably every time. Execute. Furthermore, when performing a solvent removal process, whenever the said printing process passes once, the tension concerning the blanket 2 is 1-50 kN, for example, Preferably, it is 10-30 kN. Moreover, the contact time of the blanket 2 and the solvent absorption sheet 6 is 10 to 50 seconds, for example, Preferably, it is 15 to 30 seconds.

  In the solvent removal step, when the pair of tension rollers 7 and 8 are moved downward in the vertical direction and the solvent absorbent sheet 6 is brought into contact with the outer peripheral surface of the blanket 2, both ends of the solvent absorbent sheet 6 are previously connected to the pair of reels 20. , 21, and the solvent absorbing sheet 6 may be sent out or wound up appropriately on each reel 20, 21. In particular, when the solvent absorbing sheet 6 is held in tension by the pair of tension rollers 7 and 8, the tension applied to the solvent absorbing sheet 6 by the reels 20 and 21 can be adjusted.

  In a state where the solvent absorbing sheet 6 is brought into contact with the entire printing area of the blanket 2 and is kept in a tension state (see FIG. 3C), the rotation of the blanket cylinder 3 is fixed and the blanket 2 moves in the circumferential direction. It is preferable not to do so. Thereby, the removal efficiency of the ink solvent from the blanket 2 can be increased, and the friction on the outer peripheral surface of the blanket and the accompanying deterioration can be reduced.

  In the above description, the solvent absorbent sheet 6 is brought into contact with the entire printing area of the blanket 2. However, as long as the solvent absorbent sheet 6 is held in a tensioned state with respect to the blanket 2, the solvent absorbent sheet 6 is removed. The ink solvent can be efficiently removed from the blanket 2 without contacting the entire printing area of the blanket 2. However, in this case, after bringing the solvent absorbent sheet 6 and the blanket 2 into contact with each other for a predetermined time, the blanket cylinder 3 is rotated, and the portion of the printing area of the blanket 2 that is not in contact with the solvent absorbent sheet 6 and the solvent It is necessary to arrange the absorbent sheet 6 so as to be newly brought into contact with the solvent absorbent sheet 6 and the blanket 2 again.

  When the solvent removal step is repeatedly executed, a large amount of ink solvent soaks into the solvent absorption sheet 6 and becomes saturated, so that the solvent absorption sheet 6 does not newly absorb the ink solvent. Specifically, for example, a series of the above-described series using the solvent absorbing sheet 6 in which the solvent absorbing layer 13 is made of a urethane resin and the ink having a relatively high boiling point (about 200 to 280 ° C.) glycol ester as a solvent. When the printing process is performed, the solvent absorbing sheet 6 is saturated by repeatedly performing the solvent removal step about 30 to 100 times, and approximately about 50 times. In this case, for example, by replacing the solvent absorbing sheet 6 with a new one, it is possible to prevent the solvent absorption effect from being lowered. Moreover, when using the long solvent absorption sheet 6 and winding this around the pair of rolls 20 and 21 in advance, the portion saturated with the ink solvent in the solvent absorption sheet 6 is appropriately wound, By sending out unused parts, it is possible to prevent the solvent absorption effect from being lowered. In particular, in this case, the trouble of exchanging the solvent absorbent sheet 6 can be saved, and a reduction in printing productivity can be prevented.

In the above description, the pair of tension rollers 7 and 8 have been described as members that hold the solvent absorbing sheet in a tension state, but the holding member is, for example, a member that fixes both ends of the solvent absorbing sheet. Also good.
Moreover, although the solvent absorption sheet 6 was demonstrated as what was wound around a pair of reels 20 and 21, the solvent absorption sheet 6 may be an endless belt which connected the both ends.

According to the printing apparatus and the printing method using the printing apparatus, the ink solvent that has penetrated and accumulated in the blanket 2 can be efficiently removed. Therefore, for example, it is possible to suppress an ink transfer failure or a decrease in pattern dimensional accuracy during continuous printing.
The printing apparatus and the printing method using the printing apparatus are suitable for high-precision printing such as color filter layer and black matrix print formation in a liquid crystal color filter and electrode pattern print formation on an electrode substrate of a PDP display. .

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.
Printing test The materials, members, and equipment used in the printing test are as follows.
The ink includes 100 parts by weight of a polyester resin (trade name “Pyronal (registered trademark)”, Toyobo Co., Ltd.) and 20 parts by weight of a melamine resin (trade names “Sumimar (registered trademark)”, Sumitomo Chemical Co., Ltd.). And 20 parts by weight of butyl carbitol acetate (solvent, Kishida Chemical Co., Ltd., boiling point 248 ° C.) and 20 parts by weight of Pigment Red 177 (Anthraquinone red pigment, Nagase Sangyo Co., Ltd.) What was mixed and disperse | distributed with the disperser (made by Shinki) was used.

  The intaglio (printing plate) 4 has a predetermined pattern (etched with hydrofluoric acid on the surface of a soda lime glass substrate (width 400 mm, length 500 mm, thickness 4.8 mm, Nippon Sheet Glass Co., Ltd.). Recessed) was used. On the surface of the substrate, a stripe pattern was formed in which 1280 patterns having a width of 100 μm, a depth of 10 μm, and a length of 300 mm were arranged in parallel at a pitch of 270 μm.

A substrate made of soda lime glass (width 400 mm, length 300 mm, thickness 0.7 mm, Nippon Sheet Glass Co., Ltd.) was used as the substrate (printed body) 5.
The blanket 2 is a silicone having a layer thickness of 0.9 mm in which a surface printing layer made of silicone rubber having a thickness of 0.55 mm is formed on a support film layer made of polyethylene terephthalate (PET) film having a thickness of 0.35 mm. A blanket was used.

  The solvent absorbing sheet 6 is made of polyethylene terephthalate base material 14 (width 450 mm, length 10 m, thickness 100 μm), and urethane resin (trade name “KU-7002”, Hitachi Chemical Co., Ltd.) on the surface. A laminate including the solvent absorption layer 13 which was uniformly applied and cured so as to have a thickness of 500 μm was used. The elastic modulus (Young's modulus, 25 ° C.) of the solvent absorption layer 13 was 0.07 MPa.

As the printing machine, a flat type precision printing machine manufactured by Nakan Co., Ltd. was used.
The printing conditions during the printing test are as follows.
The printing speed is 200 mm at the peripheral speed of the blanket 2 in both the ink carrying process (transfer process of ink from the intaglio 4 to the blanket 2) and the printing process (transfer process of ink from the blanket 2 to the substrate 5). / S.

The printing pressure was set so that the pressing amount of the blanket 2 was 100 μm.
In the printing test, a stripe pattern was printed on a total of 200 substrates 5 by intaglio offset printing using the materials, members, and apparatuses described above. Further, the line width (μm) of the printed stripe pattern was measured every time 10 sheets were printed on the substrate 5. The result is shown in FIG.

In the following Examples 1 and 2 and Comparative Example 1, the solvent removal step was performed each time a series of printing processes including an ink carrying step and a printing step were performed once. Moreover, according to the measurement result of the line width of the printed stripe pattern, the tension applied to the blanket 2 was adjusted in the range of 20 to 30 kN.
Example 1
In the solvent removal step of the printing test, as shown in FIG. 3C, the solvent absorbing sheet 6 was brought into contact with the entire printing area of the blanket 2 in the outer peripheral surface of the blanket 2.

Example 2
In the solvent removal step of the printing test, as shown in FIG. 4, the solvent absorbing sheet 6 is brought into contact with a substantially half region of the outer peripheral surface of the blanket 2, and the contact time between the blanket 2 and the solvent absorbing sheet 6 is 15 seconds. It was. Moreover, after making the blanket 2 and the solvent absorption sheet 6 contact for 15 seconds, the blanket cylinder 3 is rotated and the remaining half area (area not in contact with the solvent absorption sheet 6) of the outer peripheral surface of the blanket 2 However, it arrange | positioned so that the solvent absorption sheet 6 may be contacted. In this way, the solvent absorbing sheet 6 was brought into contact with approximately half of the outer peripheral surface of the blanket 2 again.

Comparative Example 1
In the solvent removal step of the printing test, as shown in FIG. 5, the outer peripheral surface of the blanket 2 and the solvent absorbing sheet 6 were brought into contact while rotating the blanket cylinder 3 at a peripheral speed of 20 mm / s. Further, the solvent absorbing sheet 6 is gradually fed from one reel 20 so that the solvent absorbing sheet 6 moves according to the rotation of the blanket 2 without applying any particular tension to the solvent absorbing sheet 6, and on the downstream side. The other reel 21 was gradually wound up.

Comparative Example 2
Stripe pattern printing was repeated in the same manner as in the printing test except that the solvent removal step was not performed.
As a result, as shown in FIG. 6, in Example 1, the change in the line width of the stripe pattern can be suppressed within ± 3 μm, and the variation in the line width of the stripe pattern in the substrate 5 can be suppressed within ± 3 μm. It was. Moreover, the contact time of the blanket 2 and the solvent absorption sheet 6 was 15 seconds on average.

In Example 2, the change in the line width of the stripe pattern can be suppressed within ± 4 μm, and the variation in the line width of the stripe pattern in the substrate 5 can be suppressed within ± 5 μm. Moreover, the contact time of the blanket 2 and the solvent absorption sheet 6 was 15 seconds on average.
The results of Examples 1 and 2 were very good because the printing accuracy required for precision printing such as the color filter layer of the liquid crystal color filter was sufficiently cleared.

  In addition, the measured value of the printing line width was an average value of values measured at five points in the surface of the substrate 5 (printed body) for every 10 printed sheets. For the printing of the color filter layer of the liquid crystal color filter, the transition of the printing line width is required to be within ± 5 μm. Further, the variation in the pattern line width was determined based on the values measured at five points in the surface of the substrate 5 (printed body), and if the variation in these values was within 5 μm, it was judged as acceptable. Further, the time required for the process of removing the ink solvent from the solvent absorber 6 was calculated as the processing time required to make the change over time of the line width of the pattern constant.

  On the other hand, in Comparative Example 1, the change in the line width of the stripe pattern was ± 11 μm, and the variation in the line width of the stripe pattern in the substrate 5 was ± 8 μm. This result does not satisfy the printing accuracy required for precision printing such as the color filter layer of the liquid crystal color filter. Moreover, in the comparative example 1, the contact with the blanket 2 and the solvent absorption sheet 6 was performed for 45 seconds on average.

In Comparative Example 2, as soon as the printed line width was less than 70 μm, a defective transfer of ink from the blanket 2 to the substrate 5 occurred. In Comparative Example 2, the printing process was stopped when a transfer failure occurred.
The present invention is not limited to the above description, and various design changes can be made within the scope of the matters described in the claims.

1 is a schematic apparatus configuration diagram showing an embodiment of a printing apparatus of the present invention. (A)-(c) is sectional drawing which shows one Embodiment of a solvent absorption sheet. (A)-(c) is explanatory drawing which shows the lapping operation | movement of a solvent absorption sheet. FIG. 6 is an explanatory diagram showing a solvent removal step in Example 2. 6 is an explanatory diagram showing a solvent removal step in Comparative Example 1. FIG. It is the graph which compared the effect of the solvent absorption process in an Example and a comparative example.

Explanation of symbols

  1: printing device, 2: blanket, 3: blanket cylinder, 6: solvent absorbing sheet (solvent absorber), 7: tension roller (holding member), 8: tension roller (holding member).

Claims (4)

A blanket for carrying the ink transferred to the substrate to be printed on the surface, a blanket cylinder for fixing the blanket to the surface, and a solvent of the ink that has oozed into the blanket due to contact with the outer peripheral surface of the blanket And a pair of holding members for holding the solvent absorber,
In the solvent removal process of sucking and removing the solvent of the ink soaking into the blanket, the solvent absorber is in contact with the outer peripheral surface of the blanket, and the pair of holding members are in the circumferential direction of the blanket The printing apparatus is characterized in that the printing apparatus is arranged opposite to the outer peripheral surface of the blanket with a space therebetween to hold the solvent absorber in a tensioned state.   2. The printing apparatus according to claim 1, wherein the solvent absorber is in contact with at least the entire blanket printing region in the blanket during the solvent removal process. A blanket for carrying the ink transferred to the substrate to be printed on the surface, a blanket cylinder for fixing the blanket to the surface, and a solvent of the ink that has oozed into the blanket due to contact with the outer peripheral surface of the blanket A printing method using a printing apparatus comprising: a solvent absorber for absorbing water; and a pair of holding members for holding the solvent absorber,
An ink carrying process for carrying ink on the surface of the blanket, a printing process for printing the ink carried on the surface of the blanket on a printing medium, and a solvent removal for absorbing and removing the solvent of the ink that has permeated into the blanket. A process,
In the solvent removal step, the solvent absorber is brought into contact with the outer peripheral surface of the blanket, and the pair of holding members are arranged opposite to the outer peripheral surface of the blanket at a distance from each other in the circumferential direction of the blanket, A printing method, wherein the solvent absorber is held in a tension state.   4. The printing method according to claim 3, wherein, in the solvent removal step, the solvent absorber is brought into contact with at least the entire blanket printing region of the blanket. 5.

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