WO2010134120A1

WO2010134120A1 - Printing device and printing method

Info

Publication number: WO2010134120A1
Application number: PCT/JP2009/002181
Authority: WO
Inventors: 淳越智; 康彦近藤
Original assignee: 住友ゴム工業株式会社
Priority date: 2009-05-18
Filing date: 2009-05-18
Publication date: 2010-11-25
Also published as: CN102427945A; KR101564130B1; KR20120022710A

Abstract

Provided is a printing device and a printing method wherein ink solvent permeated a blanket and stored therein due to repetitive print processing is removed efficiently, and poor transfer of ink or fall of dimensional precision of a pattern can be controlled at the time of continuous printing. A solvent absorption sheet (6) is brought into contact with the outer surface of a blanket (2) under stretched state by means of lapping mechanisms (7, 8, 9, 10, 11, 12, 30). The solvent absorption sheet (6) maintains a lapping state where the outer surface of at least one half of the blanket (2) is covered. Consequently, ink solvent stored in the blanket (2) is absorbed efficiently by the solvent absorption sheet (6).

Description

Printing apparatus and printing method

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 by offset printing, reverse printing, and the like.

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

However, since the electrode substrate of the liquid crystal color filter or PDP is a substrate that does not absorb the ink solvent such as glass, the solvent of the ink penetrates and accumulates in the blanket by repeating the printing process, and the blanket swells. For this reason, the transfer failure of ink, the fall of the dimensional accuracy of a pattern will arise, and the problem of an increase in inferior goods arises.
On the other hand, there is the following as a technique for removing the ink solvent which has permeated and accumulated in the blanket from the blanket.
Patent Document 1 proposes a solvent absorbing mechanism that causes a blanket and a solvent absorber to be in rotational contact.
Patent Document 2 proposes a mechanism for pressing a moisture absorbing sheet against a blanket and adjusting the wet state of the blanket by the ink solvent.
In Patent Document 3, a solvent absorbing material is formed in a tape shape wound around a roller, and the solvent absorbing material is sequentially fed out and brought into contact with a part of the circumferential surface of the blanket to make silicone of the blanket (transfer body roller). An apparatus for transferring an ink solvent from a rubber layer to a solvent absorber has been described (see FIG. 3 of Patent Document 3).
Patent Document 4 describes a printing apparatus in which a solvent absorber formed in an endless belt shape or a roll shape is brought into contact with the surface of a blanket, and ink solvent is absorbed from the rubber layer on the blanket surface (Patent Document 4) See Figure 1).

Unexamined-Japanese-Patent No. 2000-158633 JP 2000-158620 A JP-A-8-156388 JP, 2006-035769, A

The mechanisms described in

Patent Documents

1 and 2 have a problem that the contact area between the blanket and the solvent absorber (hygroscopic sheet) is small, and the efficiency of absorbing the solvent from the blanket is low. For this reason, it takes time to remove the solvent from the blanket, which reduces the printing productivity.
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, the blanket (the transfer roller in Patent Document 3) Since 4) and the solvent absorber in contact with it so-called corotation, there is a problem that the efficiency of absorbing the solvent from the blanket is low.

An object of the present invention is a printing apparatus capable of efficiently removing an ink solvent which has penetrated and accumulated in a blanket by repeated printing processing, and which can prevent ink transfer failure and pattern dimensional accuracy deterioration during continuous printing, and It is to provide a printing method.
Another object of the present invention is to provide a mechanism and method for efficiently sucking out the solvent from the blanket.

In order to achieve the above object, a printing apparatus according to the present invention comprises a blanket for carrying an ink to be transferred onto a printing substrate, a blanket cylinder for fixing the blanket on the circumferential surface, and a contact with the blanket And a pair of holding members for holding the solvent absorber, and a solvent absorber for absorbing the solvent of the ink which has spread into the blanket.
At the time of solvent removal processing for absorbing and removing the solvent of the ink which has penetrated into the blanket, the pair of holding members brings the solvent absorber into tension contact with at least half of the outer surface of the blanket for wrapping And a lapping processing mechanism for performing the processing.

In the printing apparatus described above, the solvent absorber contacts the outer surface of the blanket at the time of solvent removal processing for absorbing and removing the solvent of the ink that has been infiltrated into the blanket. Further, the pair of holding members are arranged to face each other on the outer peripheral surface of the blanket at intervals in the circumferential direction of the blanket, and hold the solvent absorbent in a tension state. Thus, the solvent absorber contacts the broad area of at least half the outer surface, as viewed in the circumferential direction of the blanket, and because of the tension, it is pressurized in the inward direction of the blanket and adheres to the outer surface of the blanket.

Therefore, according to the printing apparatus, the ink solvent which has permeated and accumulated in the blanket by the lapping process can be efficiently absorbed and removed during the solvent removing process. Moreover, thereby, the transfer defect of the ink at the time of continuous printing and the fall of the dimensional accuracy of a pattern can be suppressed, maintaining the productivity of printing.
The printing apparatus according to the present invention is characterized in that the solvent absorber is brought into contact with substantially the entire outer surface of the blanket by the pair of holding members. In this case, the removal efficiency of the ink solvent infiltrated and accumulated in the blanket can be further improved.

In the printing method according to the present invention for achieving the above object, a blanket for carrying ink to be transferred to a printing substrate, a blanket cylinder for fixing the blanket, and contact between the blanket and the blanket A printing method using a printing apparatus comprising: a solvent absorber for absorbing a solvent of ink which has been infiltrated into a blanket; and a pair of holding members for holding the solvent absorber,
The ink carrying step of carrying the ink on the surface of the blanket, the printing step of printing the ink carried on the surface of the blanket on the printing material, and the solvent removal of the solvent of the ink which has been soaked in the blanket Process, and
The solvent removal step is characterized in that a lapping process is performed in which the solvent absorber is brought into contact with the outer surface of at least half of the blanket in a tension state.

In the above-mentioned printing method, in the solvent removing step of absorbing and removing the solvent of the ink which has penetrated into the blanket, the pair of holding members are moved to bring the solvent absorber into contact with the outer surface of the blanket. Further, the above-mentioned solvent absorber is put in tension, and at least half of the outer surface of the blanket is brought into close contact with it in a pressurized state.
Therefore, according to the printing method, the ink solvent that has permeated and accumulated in the blanket can be efficiently absorbed and removed in the solvent removal step. Moreover, thereby, the transfer defect of the ink at the time of continuous printing and the fall of the dimensional accuracy of a pattern can be suppressed, maintaining the productivity of printing.

In the printing method of the present invention, in the lapping process in the solvent removal step, the solvent absorber is preferably brought into contact with substantially the entire outer surface of the blanket. In this case, the removal efficiency of the ink solvent infiltrated and accumulated in the blanket can be further improved.

According to the printing apparatus and printing method of the present invention, the ink solvent which has permeated and accumulated in the blanket can be efficiently removed, and the productivity of printing decreases due to the swelling of the blanket, the occurrence of ink transfer failure, and It is possible to suppress a defect such as a decrease in the dimensional accuracy of the print pattern. Such a printing apparatus and printing method of the present invention are suitable, for example, for high-precision printing by offset printing, reverse printing, etc., particularly, printing formation of a color filter layer of a liquid crystal color filter, a silver electrode of PDP, etc.

It is a general | schematic apparatus block diagram which shows one Embodiment of the printing apparatus of this invention. (A)-(c) is a sectional view showing one embodiment of a solvent absorption sheet. (A) to (c) are explanatory views showing the lapping operation of the solvent absorbing sheet. FIG. 7 is an explanatory view showing a solvent removing step in Example 2; FIG. 10 is an explanatory view showing a solvent removing step in Comparative Example 1; It is the graph which compared the effect of the solvent absorption process in an Example and a comparative example.

FIG. 1 is a schematic explanatory view showing an embodiment of a printing apparatus according to the present invention, and FIG. 2 (a) to FIG. 2 (c) are sectional views showing an example of a solvent absorber. ) To FIG. 3 (c) are explanatory views showing the lapping operation of the solvent absorber. Hereinafter, one embodiment of the printing apparatus and printing method of the present invention will be described in detail with reference to these figures.
Referring to FIG. 1, the printing apparatus 1 includes a blanket 2, a blanket cylinder 3 fixing the blanket 2 to the circumferential surface, an intaglio 4 as a printing plate, and a substrate 5 as a printing medium. There is.

Further, in the printing method using the printing apparatus 1, an ink carrying step of carrying the ink on the surface of the blanket 2 and a printing step of printing the ink carried on the surface of the blanket 2 on the substrate 5 are performed.
The blanket 2 comprises a support film layer and a surface print layer covering the surface (outer surface) of the support film layer.

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

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

The blanket 2 is wound around the circumferential surface of the cylindrical blanket cylinder 3 and is rotatable with the blanket cylinder 3.
For example, a metal cylinder or the like is used for the blanket cylinder 3. The blanket cylinder 3 is held so that rotational movement is free and parallel movement in a direction orthogonal to the axial direction of the blanket cylinder 3 is free. Specifically, while the outer surface of the blanket 2 fixed to the circumferential surface is in contact with the intaglio 4 and the substrate 5 described later, it is held rollably on the intaglio 4 and the substrate 5. Furthermore, the blanket cylinder 3 is in a direction perpendicular to the axial direction so that the outer surface of the blanket 2 and the solvent absorbing sheet 6 can contact each other by relative movement between a pair of

tension rollers

7 and 8 described later. Parallel movement is free.

The outer diameter of the blanket cylinder 3 around which the blanket 2 is wound is appropriately selected according to the area of the printing area. In addition, the outer surface of the area | region except the part inserted in the groove part of the blanket cylinder 3 and the vicinity of the said groove part can be made into the printing area | region of the blanket 2. FIG.
The blanket may have, for example, a cylindrical shape having a cylindrical sleeve and a surface print layer formed on the outer peripheral surface of the cylindrical sleeve. In this case, the cylindrical blanket is used by being fitted and fixed to the outer peripheral surface of the cylindrical blanket cylinder. In this case, the entire circumferential direction of the blanket can be used as the printing area. Therefore, an arbitrary region according to the size of the printing material is selected on the outer peripheral surface of the blanket.

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

The substrate 5 is not particularly limited, and is appropriately selected according to the purpose and application of printing.
The ink is not particularly limited, and various inks are used in accordance with the purpose and application of printing. For example, in the formation of a color filter layer or a black matrix of a liquid crystal color filter, a resin, a solvent, a pigment and, if necessary, a pigment dispersant, an extender pigment, a curing catalyst, a leveling agent (surface tension regulator), etc. And the boiling point of the solvent is 70 to 200 ° C., and the ink having a swelling ratio 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. Be

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 the physical properties such as viscosity and thixotropy of the ink, but is preferably 1000 to 20000, more preferably 5000, in terms of standard polystyrene equivalent by GPC method. It is-15000.

The solvent preferably has a boiling point of 70 to 200.degree. Specifically, as the solvent having a boiling point of 70 to 200 ° C., for example, alcohols (more preferably, higher alcohols), glycols, glycol esters, alkyl ethers, aliphatic hydrocarbons, alicyclic hydrocarbons And aromatic hydrocarbons and carboxylic acid esters are used.
As the pigment, when forming a color filter layer of a liquid crystal color filter, for example, anthraquinone red pigment, halogenated phthalocyanine green pigment, phthalocyanine blue pigment, etc. are used, and yellow pigment, violet pigment etc. It is used as an auxiliary pigment. Further, in the case of forming a black matrix of a liquid crystal color filter, for example, carbon black, iron oxide (iron black), titanium black, iron sulfate, alloys such as Fe-Co-Mo, and the like are used. The average primary particle size of the pigment is preferably 1 to 100 nm.

The swelling ratio is an index relating to the absorption speed of the ink solvent in the surface print layer of the blanket 2 and the degree of repelling of the ink. The swelling ratio is preferably 10 to 50%, more preferably 10 to 30%, in the above range.
Further, the above-described ink is prepared, for example, by blending the above-mentioned 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 adopted for the ink carrying step. In this case, for example, the ink is applied to the entire surface of the printing area in the outer peripheral surface of the blanket 2, and then the blanket 2 is rolled on the concavo-convex plate as a printing plate to contact the convexes of the concavo-convex plate The ink in the above-mentioned portion 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 reverse pattern which is reverse to the printing pattern to be printed on the substrate 5. On the other hand, an ink pattern corresponding to the printing pattern to be printed on the substrate 5 is formed on the outer peripheral surface of the blanket 2.

In the printing step of the printing method, the ink pattern is transferred onto the surface of the substrate 5 by rolling the blanket 2 having the ink pattern transferred from the intaglio 4 on the substrate 5 while contacting the substrate 5. . Thus, an ink pattern corresponding to the printing pattern is printed on the substrate 5.
The printing apparatus 1 further absorbs the solvent of the ink absorbed into the blanket 2 by contact with the outer peripheral surface of the blanket 2 and absorbs the solvent of the solvent absorbing sheet 6 as a solvent absorber, and at the time of solvent removal processing described later (solvent removal step) A pair of

tension rollers

7 and 8 as holding members for holding the solvent absorbing sheet 6 in tension, a pair of

cranks

9 and 10 for moving the

tension rollers

7 and 8 to a predetermined position, and a pair of arms The control unit 30 controls movement of the

cranks

11 and 12 and the

cranks

9 and 10 and the

arms

11 and 12. A lapping mechanism is realized by the rollers, the crank, the arm, and the control unit. The control unit 30 includes a servo mechanism and the like, controls the rotation of the

reels

20 and 21 in addition to the movement of the

cranks

9 and 10 and the

arms

11 and 12, and intermittently conveys the solvent absorbing sheet 6 .

Further, in the printing method using the printing apparatus 1, a solvent removing step is further performed in which a solvent absorbing sheet 6 sucks the solvent of the ink which has penetrated into the blanket 2 and removes the solvent from the blanket 2.
The solvent absorption sheet 6 is a long member provided with a solvent absorption layer on the surface on the side in contact with the outer peripheral surface (outer surface) of the blanket. Examples of the layer configuration of the solvent absorbing sheet 6 include the following.
· A laminate comprising a solvent absorption layer 13 and a base 14 for fixing the solvent absorption layer 13 (see FIG. 2 (a))
A laminate in which the solvent absorbing layer 13, the base 14, and the elastic layer 15 are laminated in this order (see FIG. 2 (b))
A laminated body in which the solvent absorption layer 13, the elastic layer 15, and the base material 14 are laminated in this order (see FIG. 2 (c))
Although the layer configuration of the solvent absorbing 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. Also, for example, a laminate having a three-layer structure provided with an elastic layer 15 as shown in FIG. 2 (b) or FIG. 2 (c) is adjusted according to the type of ink solvent, the material of the surface printing layer of the blanket 2, etc. And can be adopted as appropriate.

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

The surface roughness of the solvent absorbing layer 13 is not limited to this, but from the viewpoint of preventing 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, but the distortion is prevented when the solvent absorbing layer 13 is in contact with the outer peripheral surface of the blanket 2 and held in tension by the pair of tension rollers (holding members) 7 and 8 From the viewpoint of securing the absorption capacity of the ink solvent by the solvent absorption layer 13, the thickness is, for example, 100 to 2000 μm, preferably 300 to 1500 μm.

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

For the elastic layer 15, for example, solid rubber, foamed rubber, soft resin and the like are used, and preferably soft urethane resin and the like are used. The thickness of the elastic layer 15 is, for example, 0.1 to 5 mm, preferably 0.2 to 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 the compression elastic modulus at 1% compression time.

The total thickness of the solvent absorbing sheet 6 is not limited to this, but is preferably 200 to 1000 μm.
The pair of

tension rollers

7 and 8 includes the rotational movement of the

cranks

9 and 10 and the accompanying movement of the

arms

11 and 12, and the

cranks

9 and 10 and the

arms

11 and 12 around the

fulcrums

16 and 17 of the

cranks

9 and 10. By rotational movement, it moves to a predetermined position for lapping. That is, a lapping operation is performed in which the solvent absorbing sheet 6 covers the outer peripheral surface of the blanket 2 (see FIGS. 3A to 3C).

In the above-described ink carrying process and printing process, the pair of

tension rollers

7, 8 abut against 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 removing step, that is, at the time of solvent removing processing by the solvent absorbing sheet 6, the control parts 30 (see FIG. 1) Counterclockwise, the crank 10 is pivoted clockwise and the

arms

11, 12 are pivoted in the opposite direction. As a result, the

cranks

9 and 10 and the

arms

11 and 12 move to a position extending substantially downward in the vertical direction. The movement of the

cranks

9 and 10 and the

arms

11 and 12 moves the pair of

tension rollers

7 and 8 downward in the vertical direction, and the solvent absorbing sheet 6 held by the

tension rollers

7 and 8 has an upper outer periphery of the blanket 2 It contacts the surface (see FIG. 3 (b)).

Next, the control unit 30 maintains the connected state of the

cranks

9 and 10 and the

arms

11 and 12 in the same state, and pivots around the

fulcrums

16 and 17 in directions opposite to each other. As a result, the solvent absorbing sheet 6 is brought into contact with substantially the entire printing area of the blanket 2. At this time, since the pair of

tension rollers

7 and 8 holds the solvent absorbing sheet 6 in a tension state, the solvent absorbing sheet 6 is brought into contact with the blanket 2 in a pressurized state.

The lapping operation of the solvent absorbent sheet 6 is not limited to the series of operations shown in FIGS. 3 (a) to 3 (c). For example, after the 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

respective tension rollers

7 and 8 are arranged along the outer peripheral surface of the blanket 2, The circumferential direction may be moved in opposite directions. In this case, the adhesion between the solvent absorbing sheet 6 and the outer peripheral surface of the blanket 2 can be further enhanced.

The lapping process in the solvent removal process may be performed, for example, every time a series of printing processes consisting of an ink carrying process and a printing process is performed, or every time the series of printing processes is performed a plurality of times. It is also good. The frequency of the solvent removal step may be set appropriately depending on the extent to which the ink solvent has penetrated into the blanket 2. The extent to which the solvent of the ink has penetrated into the blanket 2 is, for example, an imaging means that does not illustrate the shape of the ink pattern printed on the substrate 5 (for example, the planar or three-dimensional shape such as size, thickness, or cross-sectional shape) It can be determined based on the temporal change of the ink pattern shape by measuring (for example, a CCD camera or the like) or image analysis means.

Further, in a state in which the pair of

tension rollers

7 and 8 is in contact with the outer peripheral surface of the blanket 2 and holds the blanket 2 in tension (see FIG. 3C), the tension applied to the blanket 2 or the blanket The contact time between 2 and the solvent absorbing sheet 6 may be appropriately set depending on the extent to which the ink solvent has penetrated into the blanket 2 and the degree to which the ink solvent is easily absorbed from the blanket 2.

For example, when printing a color filter layer of a liquid crystal color filter using a silicone blanket and an ink containing a glycol ester having a relatively high boiling point (about 200 to 280.degree. C.) as a solvent, printing is performed. In view of the fact that the ink pattern to be used is very fine and extremely high printing accuracy is required, the solvent removal step is carried out, for example, every one to ten times of the above-mentioned printing process, preferably once every time Run. Furthermore, when the solvent removal step is performed each time the printing process is performed, the tension applied to the blanket 2 is, for example, 1 to 50 kN, preferably 10 to 30 kN. The contact time between the blanket 2 and the solvent-absorbent sheet 6 is, for example, 10 to 50 seconds, preferably 15 to 30 seconds.

In the solvent removing step, when the pair of

tension rollers

7 and 8 are moved downward in the vertical direction to bring the solvent absorbing sheet 6 into contact with the outer peripheral surface of the blanket 2, both ends of the solvent absorbing sheet 6 are previously paired with the reels 20. , 21 and the solvent absorbing sheet 6 may be fed out or taken up by the

reels

20 and 21 as appropriate. 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 can be adjusted by each of the

reels

20 and 21.

In a state where the solvent absorbing sheet 6 is in contact with the entire surface of the printing area of the blanket 2 and held in tension (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 Thereby, the removal efficiency of the ink solvent from the blanket 2 can be enhanced, and furthermore, the friction of the outer peripheral surface of the blanket and the deterioration thereof can be reduced.

In the above description, the solvent absorbing sheet 6 is brought into contact with substantially the entire printing area of the blanket 2 by the wrapping process, but as long as the solvent absorbing sheet 6 is held in tension with respect to the blanket 2, Even if the absorbent sheet 6 is not in contact with the entire surface of the printing area of the blanket 2, the ink solvent can be efficiently removed from the blanket 2. However, in this case, after the solvent absorbing sheet 6 and the blanket 2 are brought into contact with each other for a predetermined time, the blanket cylinder 3 is rotated and a portion of the printing area of the blanket 2 not in contact with the solvent absorbing sheet 6 It is necessary to arrange the absorbent sheet 6 so as to be in new contact, and to bring the solvent absorbent sheet 6 and the blanket 2 into contact again.

When the solvent removing step is repeatedly performed, a large amount of ink solvent soaks into the solvent absorbing sheet 6 to be saturated, so that the solvent absorbing sheet 6 does not newly absorb the ink solvent. Specifically, for example, using the solvent absorbing sheet 6 in which the solvent absorbing layer 13 is made of a urethane resin, and the ink using a glycol ester having a relatively high boiling point (about 200 to 280 ° C.) as a solvent, When the printing process is performed, the solvent absorbing sheet 6 is saturated by repeatedly performing the solvent removing step approximately 30 to 100 times, approximately 50 times. In this case, for example, by replacing the solvent absorbing sheet 6 with a new one, it is possible to prevent a drop in the solvent absorption effect. When a long solvent-absorbent sheet 6 is used and previously wound around a pair of

rolls

20 and 21, the portion of the solvent-absorbent sheet 6 that is saturated with the ink solvent is appropriately wound, By sending out the unused part, it is possible to prevent a drop in the solvent absorption effect. In particular, in this case, the trouble of replacing the solvent absorbing sheet 6 can be omitted, and a decrease in printing productivity can be prevented.

In the above description, the pair of

tension rollers

7 and 8 is described as a member for holding the solvent absorbing sheet in a tension state, but the holding member is, for example, a member for fixing both ends of the solvent absorbing sheet It is also good.
Although the solvent absorbing sheet 6 has been described as being wound around the pair of

reels

20 and 21, the solvent absorbing sheet 6 may be an endless belt having its both ends connected.

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

Hereinafter, the present invention will be more specifically described by way of examples and comparative examples.
Printing test The materials, parts and devices used for the printing test are as follows.
In the ink, 100 parts by weight of polyester resin (trade name "Pyronal (registered trademark)", Toyobo Co., Ltd.) and 20 parts by weight of melamine resin (trade name "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 dispersed with a dispersing machine (made by Shinky) was used.

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

As the substrate (printed material) 5, a substrate made of soda lime glass (width 400 mm, length 300 mm, thickness 0.7 mm, Nippon Sheet Glass Co., Ltd.) was used.
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 supporting film layer made of a polyethylene terephthalate (PET) film having a thickness of 0.35 mm. I used a blanket.

The solvent-absorbent sheet 6 comprises a base 14 made of polyethylene terephthalate (width 450 mm, length 10 m, thickness 100 μm) and a urethane resin (trade name “KU-7002”, Hitachi Chemical Co., Ltd.) on its surface. It used the layered product provided with the solvent absorption layer 13 uniformly applied and hardened so that thickness might be set to 500 micrometers. The elastic modulus (Young's modulus, 25 ° C.) of the solvent absorption layer 13 was 0.07 MPa.

As a printing machine, a flat plate precision printing machine manufactured by Nakan Co., Ltd. was used.
The printing conditions at the time of 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 (the ink transfer process from the intaglio 4 to the blanket 2) and the printing process (the ink transfer process from the blanket 2 to the substrate 5). It was set to be / s.

The printing pressure was set so that the amount of depression 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 above-described materials, members and devices. Further, every 10 printings on the substrate 5 were performed, and the line width (μm) of the printed stripe pattern was measured. The results are shown in FIG.

In the following Examples 1 and 2 and Comparative Example 1, the solvent removing process was performed every time after a series of printing processes consisting of the ink carrying process and the printing process. Further, the tension applied to the blanket 2 was adjusted in the range of 20 to 30 kN according to the measurement result of the line width of the printed stripe pattern.
Example 1
In the solvent removal process of the printing test, as shown in FIG. 3C, the solvent absorbing sheet 6 is brought into contact with the entire surface of the printing area of the blanket 2 out of 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 approximately half 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. And After contacting the blanket 2 and the solvent absorbing sheet 6 for 15 seconds, the blanket cylinder 3 is rotated and the remaining half of the outer peripheral surface of the blanket 2 (the area not in contact with the solvent absorbing sheet 6) Were placed in contact with the solvent absorbing sheet 6. Thus, the solvent absorbing sheet 6 was again brought into contact with approximately half of the outer peripheral surface of the blanket 2.

Comparative Example 1
In the solvent removing step of the printing test, as shown in FIG. 5, the outer peripheral surface of the blanket 2 was brought into contact with the solvent absorbing sheet 6 while rotating the blanket cylinder 3 at a peripheral speed of 20 mm / s. In addition, the solvent absorbing sheet 6 is gradually fed out from one of the reels 20 so that the solvent absorbing sheet 6 moves with the rotation of the blanket 2 without applying special tension, and at the downstream side , And gradually wound on the other reel 21.

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

Further, in Example 2, the line width change of the stripe pattern can be suppressed within ± 4 μm, and the variation of 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 Example 1 and Example 2 are extremely good, as they sufficiently clear the printing accuracy required for precision printing of color filter layers of liquid crystal color filters and the like.

In addition, the measured value of the printing line width was taken as the average value of the values measured at five points in the plane of the substrate 5 (printed material) every 10 printed sheets. Printing of a color filter layer of a liquid crystal color filter is required to have a transition of printed line width within ± 5 μm. Further, the variation of the pattern line width was judged by the values measured at five points in the plane of the substrate 5 (to-be-printed), and it was regarded as acceptable if the variation of these values was within 5 μm. Further, the time required for the process of removing the ink solvent from the solvent absorber 6 was calculated as the process time required to make the change with time of the line width of the pattern constant.

On the other hand, in Comparative Example 1, the line width change of the stripe pattern was ± 11 μm, and the variation of 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 of color filter layers of liquid crystal color filters and the like. Moreover, in the comparative example 1, the contact with the blanket 2 and the solvent absorption sheet 6 was performed on average for 45 seconds.

In Comparative Example 2, as soon as the printing line width fell below 70 μm, a transfer failure of the 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: printing apparatus 2: 2: blanket 3: 3: blanket cylinder 6: 6: solvent absorbing sheet (solvent absorber) 7: 7: tension roller (holding member) 8: tension roller (holding member) 30: control unit

Claims

A blanket for carrying ink transferred to a substrate, a blanket cylinder for fixing the blanket on the circumferential surface, and a solvent for the ink which has been absorbed in the blanket by contact with the blanket A solvent absorber, and a pair of holding members for holding the solvent absorber;
At the time of solvent removal processing for absorbing and removing the solvent of the ink which has penetrated into the blanket, the pair of holding members brings the solvent absorber into tension contact with at least half of the outer surface of the blanket for wrapping A printing apparatus, comprising:
The printing apparatus according to claim 1, wherein the solvent absorber is brought into contact with substantially the entire outer surface of the blanket by the pair of holding members.
A blanket for carrying ink transferred to a substrate, a blanket cylinder for fixing the blanket, and a solvent absorber for absorbing the solvent of the ink which has been absorbed into the blanket by contact with the blanket And a pair of holding members for holding the solvent absorber.
The ink carrying step of carrying the ink on the surface of the blanket, the printing step of printing the ink carried on the surface of the blanket on the printing material, and the solvent removal of the solvent of the ink which has been soaked in the blanket Process, and
The method according to claim 1, wherein the solvent removing step includes a lapping process in which the solvent absorber is brought into contact with the outer surface of at least a half of the blanket in a tension state.
The printing method according to claim 3, wherein in the lapping process in the solvent removal step, the solvent absorber is brought into contact with substantially the entire outer surface of the blanket.