JP4616323B2 - Printing apparatus and printing method - Google Patents

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).

Furthermore, the invention described in Patent Document 4 describes a heater for heating the solvent absorber and evaporating the solvent as a solvent removal means for removing the solvent from the solvent absorber (FIG. 1 (a) and (Refer FIG.1 (b)).
JP 2000-158633 A JP 2000-158620 A JP-A-8-156388 JP 2006-035769 A

  However, in the inventions described in Patent Documents 1 to 4, when the process of transferring the ink solvent from the blanket with the solvent absorbing means (solvent absorber, moisture absorbing sheet and solvent absorber) is repeated, the ink solvent penetrates into the solvent absorbing means, As a result, the solvent absorbing means is saturated with the ink solvent. In order to eliminate the lowering of the sucking action due to the saturation of the ink solvent, for example, the solvent absorbing means may be replaced. In this case, however, the printing productivity is reduced and the cost is increased.

Moreover, in the ink for forming the color filter layer of the liquid crystal color filter, glycol esters having a relatively high boiling point (about 200 to 280 ° C.) are generally used as a solvent, and the glycol esters are evaporated by heating. In order to achieve this, the heating temperature needs to be set extremely high.
Moreover, when it is required to print an extremely fine pattern with high accuracy, such as the above-described color filter layer, the printing apparatus is installed in a clean room, and it is in a very narrow temperature range such as ± 0.5 ° C. Strict temperature control is applied. For this reason, heating the solvent absorber with a heater entails a very large risk in terms of clean room temperature management.

  An object of the present invention is to provide a printing apparatus and a printing method capable of efficiently removing the ink solvent accumulated in the solvent absorber from the solvent absorber for absorbing and removing the ink solvent of the blanket. is there.

To achieve the above object, printing apparatus of the present invention includes a blanket for carrying ink to be transferred to the printing material on the surface, and the blanket cylinder for securing the blanket to the surface, of the blanket The solvent absorber for sucking out the solvent of the ink soaking into the blanket by contact with the outer peripheral surface, and the solvent of the ink sucked by the solvent absorber are sucked from the solvent absorber in a non-contact state and removed. Solvent blanking and removing means for carrying out, and the blanket has an ink carrying position for carrying the ink on its surface, a printing position for printing the carried ink on the printing medium, and a solvent for the soaked ink. The solvent absorber is arranged so as to be movable between the sucking positions to be sucked and the axis of the solvent absorber is parallel to the rotation axis of the blanket cylinder. It is formed in the shape of an endless belt that is stretched between two driven rollers and one tension roller, and the two driven rollers are arranged at a distance from the outer peripheral surface of the blanket. The blanket cylinder so as to be able to take two states, a separated state and a contact state arranged so as to contact each other with the solvent absorber sandwiched between the outer peripheral surface of the blanket By being arranged so as to be able to move in parallel, the ink comes into contact with the blanket at the sucking position and sucks the solvent of the ink that has oozed into the blanket, and the solvent absorbing means is configured such that the two driven rollers are separated from each other. when the state, at a distance to the contact surface of the blanket of the solvent absorber, Oh suction nozzle disposed opposite to the solvent absorber It is characterized in that.

Above Kishirushi printing apparatus, the solvent of the ink that has been sucked from the blanket to the solvent absorber and the solvent absorber at the non-contact state, suction by the solvent removed by suction means, can be removed from the solvent absorber . Therefore, according to the above Kishirushi printing apparatus, damage to the solvent absorption surface caused by contact with the member for removing the ink solvent, the deterioration can be prevented. In addition, no heat treatment is required to remove the ink solvent from the solvent absorber, thereby preventing an excessive burden on the temperature management of the printing apparatus.

Further, the solvent removed by suction means, spaced to the contact surface of the blanket of the solvent absorber, since a suction nozzle disposed opposite to the solvent absorber is sucked from the blanket to the solvent absorber The ink solvent can be removed from the solvent absorber with a simple structure.
Further, the printing apparatus according to the present invention is configured to contact the blanket for supporting the ink transferred to the printing medium on the surface, the blanket cylinder for fixing the blanket to the surface, and the outer peripheral surface of the blanket. A solvent absorber for sucking out the solvent of the ink soaking into the blanket, and a solvent suction removing means for sucking and removing the solvent of the ink sucked into the solvent absorber from the solvent absorber in a non-contact state. The blanket is provided between an ink carrying position for carrying ink on a surface thereof, a printing position for printing the carried ink on a printing medium, and a sucking position where the solvent of the soaked ink is sucked off. The solvent absorbers are arranged in two so that the axis is parallel to the rotation axis of the blanket cylinder. A separated state in which an endless belt is formed between a driven roller and one tension roller, and the two driven rollers are spaced from each other between the outer peripheral surface of the blanket; It is arranged so as to be movable in parallel with the blanket cylinder so as to be able to take two states: an abutting state in which the solvent absorber is placed in contact with the outer peripheral surface of the blanket. In this way, the ink in contact with the blanket at the sucking position and sucking out the solvent of the ink that has oozed into the blanket is sucked, and the solvent suction removing means removes the solvent absorber from the two driven rollers and the two driven rollers. A sheath portion that is accommodated in a state of being stretched over a tension roller; and a lid portion that seals and seals the open end of the sheath portion. There when it is the separated state, the solvent absorber accommodated in the sheath, and sealed by the lid, is characterized in that a vacuum chamber for sucking the sheath portion.
In the printing apparatus, the ink solvent sucked from the blanket to the solvent absorber can be removed from the solvent absorber by being sucked by the solvent suction removing means in a non-contact state with the solvent absorber. Therefore, according to the printing apparatus, it is possible to prevent damage and deterioration of the surface of the solvent absorber due to contact with the member for removing the ink solvent. In addition, no heat treatment is required to remove the ink solvent from the solvent absorber, thereby preventing an excessive burden on the temperature management of the printing apparatus.
Further, since the solvent removed by suction means is vacuum chamber, the solvent of the ink that has been sucked from the blanket to the solvent absorber efficiently sucked from the whole of the solvent absorber can be removed. Therefore, in the case where the printing apparatus of the above SL have shifted it can also be remove ink solvent stored in the solvent absorber efficiently.

Printing methods of the present invention is a printing method using the printing apparatus of the present invention, printing and ink-carrying step of carrying the ink to the surface of the blanket, the supported ink to the surface of the blanket to the printing substrate A printing process, a solvent sucking process for sucking the solvent of the ink soaking into the blanket with the solvent absorber, and a solvent of the ink sucked by the solvent absorber with the solvent sucking and removing means in a non-contact state. And a solvent suction removing step for removal.

Above Kishirushi printing method, the above solvent blotting process, the solvent absorbed the ink and a solvent absorber from the blanket, and the solvent absorber at the non-contact state, suction by the solvent removed by suction means, solvent absorber Can be removed. Therefore, according to the above Kishirushi printing method, damage to the solvent absorption surface caused by contact with the member for removing the ink solvent, the deterioration can be prevented. In addition, the heat treatment for removing the ink solvent from the solvent absorber is unnecessary, thereby preventing an excessive burden on the temperature management of the printing apparatus.

  According to the printing apparatus and the printing method of the present invention, it is possible to efficiently remove the ink solvent that has penetrated into the solvent absorber from the solvent absorber for absorbing and removing the ink solvent of the blanket. Thereby, it is possible to prevent a decrease in printing productivity and an increase in cost due to replacement of the solvent absorber. 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.

Hereinafter, an embodiment of a printing apparatus of the present invention will be described in detail with reference to the drawings. In addition, about several embodiment, the same code | symbol is shown to the part same or the same kind, and the description may be abbreviate | omitted in embodiment shown later.
FIG. 1 is a schematic configuration diagram illustrating an embodiment of a printing apparatus according to the present invention.
In 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, a substrate 5 as a printing medium, and an outer peripheral surface of the blanket 2. A solvent absorber 6 that contacts and absorbs the ink solvent, and a first solvent suction removal means 7 that sucks and removes the ink solvent from the solvent absorber 6 in a non-contact state are provided.

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 blanket cylinder 3 is held so as to be able to roll on the intaglio 4 and the substrate 5 while bringing the outer peripheral surface of the blanket 2 fixed to the surface into contact with the intaglio 4 and the substrate 5 described later. The

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. For the printing area of the blanket 2, for example, in the circumferential direction, it is possible to select all areas except for the part inserted into the groove part of the blanket cylinder 3 and the vicinity of the groove part.
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.

The printing method using the printing apparatus 1 includes an ink carrying process for carrying the ink transferred to the printing medium on the surface of the blanket 2, a printing process for printing the ink carried on the surface of the blanket 2 on the substrate 5, and It has.
In the ink carrying step, the ink filled in the recess (not shown) of the intaglio 4 is transferred to the outer peripheral surface of the blanket 2 by rolling on the intaglio 4 while the blanket 2 is in contact with the intaglio 4. 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 step, the ink pattern is transferred onto the surface of the substrate 5 by rolling the blanket 2 to which the ink pattern has been transferred from the intaglio 4 on the substrate 5 while being in contact with the substrate 5. Thereby, an ink pattern corresponding to the print pattern is printed on the substrate 5.
In FIG. 1, a solvent absorber 6 is a member obtained by forming a long sheet having a solvent absorption layer (not shown) into an endless belt shape on at least a surface in contact with the outer peripheral surface of a blanket. Examples of the layer structure of the solvent absorber 6 include the following.
A laminate comprising a solvent absorbing layer 8 and a base material 9 for fixing the solvent absorbing layer 8 (see FIG. 2 (a)).
A laminate in which the solvent absorption layer 8, the base material 9, and the elastic layer 10 are laminated in this order (see FIG. 2B).
A laminate in which the solvent absorption layer 8, the elastic layer 10, and the base material 9 are laminated in this order (see FIG. 2C).
Although the layer structure of the solvent absorber 6 is not particularly limited, for example, a two-layer laminate shown in FIG. 2A is preferable because the structure is simple. In addition, for example, a three-layer laminate including the elastic layer 10 as shown in FIGS. 2B and 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 8 comes into 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 8, 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 absorbing layer 8 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. The thickness of the solvent absorption layer 8 is not particularly limited, but is 100 to 2000 μm, for example, from the viewpoint of securing sufficient strength and the capacity of the ink solvent to be absorbed by the solvent absorption layer 8, and preferably 300 to 1500 μm. It is.

  For the base material 9, for example, a resin film made of polyester (particularly, PET or the like), imide resin, acrylic resin, or the like is used. The thickness of the base material 9 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 absorber 6. Although the surface roughness of the base material 9 is not limited to this, from the viewpoint of ensuring the smoothness of the solvent absorbing layer 10, the arithmetic average roughness Ra is, for example, 30 to 2000 nm, and preferably 50 to 1000 nm. The mechanical strength of the substrate 9 is, for example, 70 to 500 MPa, preferably 100 to 500 MPa, as a tensile elastic modulus at 0.2% elongation.

  For the elastic layer 10, 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 absorber 6 is not limited to this, Preferably, it is 200-1000 micrometers.
In FIG. 1, the endless belt-like solvent absorber 6 includes three rollers, that is, two driven rollers 11 and 12 and one tension, whose axis is parallel to the rotation axis of the blanket cylinder 3. It is stretched between the rollers 13.

  The two driven rollers 11 and 12 absorb the solvent between the separated state (indicated by a solid line in FIG. 1) arranged with a space between the outer peripheral surface of the blanket 2 and the outer peripheral surface of the blanket 2. It is arranged so as to be movable in parallel with respect to the blanket cylinder 3 so as to be able to take two states: an abutting state (a state indicated by a dotted line in FIG. 1) arranged so as to abut each other with the body 6 in between. .

  The tension roller 13, together with the pair of driven rollers 11 and 12, is arranged so as to be movable in parallel with the blanket cylinder 3. Further, the tension roller 13 is urged in a direction away from the pair of driven rollers 11 and 12 by an urging means (not shown), thereby absorbing the solvent stretched between the rollers 11, 12 and 13. A predetermined tension is applied to the body 6.

  Therefore, in the above contact state, the solvent absorber 6 has a predetermined pressure contact force by the tension applied from the tension roller 13 in the region spanned between the pair of driven rollers 11 and 12. Pressed against the surface. In the pressure contact state, the solvent absorber 6 sucks the solvent of the ink that has permeated into the blanket 2 while being driven and rotated by the rotation of the blanket cylinder 3.

The printing method using the printing apparatus 1 further includes a solvent sucking process in which the solvent of the ink that has permeated into the blanket 2 is sucked by the solvent absorber 6 and removed from the blanket 2.
In this solvent sucking process, the two driven rollers 11 and 12 are arranged so as to be in the above-mentioned contact state. Thus, the blanket cylinder 3 is rotated, and the solvent absorber 6 is rotated along with the rotation of the blanket 2 fixed to the surface thereof. As a result, the ink that has soaked into the blanket 2 is absorbed by the solvent absorber 6.

  For example, the solvent blotting 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 series of printing processes are performed a plurality of times. What is necessary is just to set the frequency of a solvent absorption process suitably according to the grade which the solvent of an ink oozes 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.

In addition, when the solvent absorber 6 is in the above contact state, the tension applied to the blanket 2 and the contact time between the blanket 2 and the solvent absorber 6 are such that the ink solvent oozes into the blanket 2. Depending on the degree of easy absorption of the ink solvent from the blanket 2, it may be set as appropriate.
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 absorption 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 absorption process every time the said printing process passes, the tension | tensile_strength 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 absorber 6 is, for example, 10 to 50 seconds, and preferably 15 to 30 seconds.

In FIG. 1, the pair of driven rollers 11 and 12 are preferably arranged as spaced apart as possible in the circumferential direction of the blanket 2. In this case, the contact area between the outer peripheral surface of the blanket 2 and the surface of the solvent absorber 6 is increased, and the efficiency of absorbing the ink solvent from the blanket can be improved.
In FIG. 1, the first solvent suction / removal means 7 has a suction nozzle 14 disposed facing the solvent absorber 6 at a distance from the surface of the solvent absorber 6 (contact surface with the blanket 2). I have.

The suction nozzle 14 is disposed so as to face the contact surface of the solvent absorber 6 with the blanket 2 at an interval. The suction nozzle 14 is a slit nozzle that is opened in an elongated rectangular shape along the axial direction of the rollers 11 to 13 that support the solvent absorber 6. The suction nozzle 14 is connected to a vacuum pump (not shown).
The printing method using the printing apparatus 1 further includes a solvent suction removal in which the solvent of the ink sucked by the solvent absorber 6 is sucked and removed by the first solvent suction removal means 7 (suction nozzle 14) in a non-contact state. It has a process.

  In this solvent suction and removal step, first, the two driven rollers 11 and 12 that support the solvent absorber 6 are arranged so as to be in the separated state. Next, the solvent absorber 6 is rotated by the two driven rollers 11 and 12 and one tension roller 13, and the vicinity of the surface of the solvent absorber 6 is sucked by the suction nozzle 14. As a result, the vicinity of the surface of the solvent absorber 6 has a negative pressure, and the ink solvent in the solvent absorber 6 is sucked and removed from the solvent absorber 6.

  The suction nozzle 14 has an opening width (lateral opening width) along the axial direction of each of the rollers 11 to 13 from the viewpoint of making the degree of vacuum near the surface of the solvent absorber 6 as high as possible and efficiently sucking the ink solvent. The slit width (vertical opening width) along the rolling direction of the solvent absorber 6 is, for example, 3 to 1000 μm, preferably 30 to 300 μm. Is set to Moreover, from the same viewpoint, the space | interval between the surface of the solvent absorber 6 and the opening part of the suction nozzle 14 is 10-150 micrometers, for example, Preferably, it is set to 30-100 micrometers.

In addition, when the said slit space | interval (vertical opening width) exceeds the said range, while the area to attract | suck can be taken widely, attraction | suction degree falls. If the slit interval (vertical opening width) is less than the above range, the degree of suction increases, but the area to be sucked becomes very narrow, and it takes an excessive amount of time for suction per unit area. The removal efficiency may be reduced.
In addition, the distance between the surface of the solvent absorber 6 and the opening of the suction nozzle 14 is preferably as narrow as possible from the viewpoint of improving the suction efficiency of the ink solvent, but on the other hand, is less than the above range. Then, contact between the solvent absorber 6 and the suction nozzle 14 may occur, and the solvent absorber 6 may be damaged.

In the solvent suction and removal step, the moving speed of the solvent absorber 6 is, for example, 5 to 60 mm / s, preferably 10 to 40 mm / s. The time for the suction process by the suction nozzle 14 is, for example, 1 to 50 seconds, preferably 5 to 30 seconds.
When the solvent absorption step is repeated and a large amount of ink solvent soaks into the solvent absorber 6 and becomes saturated, the solvent absorber 6 no longer absorbs the ink solvent. It can suppress that the effect of the absorption process of the ink solvent from the blanket 2 by the absorber 6 falls over time. For example, as a solvent absorber 6 for performing the above-described series of printing processes using an ink having a glycol ester having a relatively high boiling point (about 200 to 280 ° C.) as a solvent, and sucking out the ink solvent from the blanket. When the solvent absorbing layer 8 is made of a urethane resin, the solvent absorber 6 is saturated by repeatedly performing the solvent sucking process about 30 to 100 times, approximately 50 times.

The first solvent suction removing means 7 shown in FIG. 1 may further include, for example, a gas nozzle 15 and an ultrasonic transducer 16 in addition to the suction nozzle 14.
For example, the gas nozzle 15 is disposed upstream of the suction nozzle 14 in the rotational direction of the solvent absorber 6. The absorption efficiency of the ink solvent from the solvent absorber 6 can be further improved by sucking with the suction nozzle 14 while jetting gas from the gas nozzle 15 to the solvent absorber 6.

  From the viewpoint of improving the suction efficiency of the ink solvent from the solvent absorber 6 by the suction nozzle 14, the gas nozzle 15 has an opening width (lateral opening width) along the axial direction of each of the rollers 11 to 13 of the solvent absorber 6. It is set to the same width as the length in the axial direction, and the slit interval (vertical opening width) along the rolling direction of the solvent absorber 6 is set to, for example, 5 to 7000 μm, preferably 20 to 500 μm. From the same viewpoint, the distance between the surface of the solvent absorber 6 and the opening of the gas nozzle 15 is set to 10 to 150 μm, preferably 30 to 100 μm, for example.

  If the slit interval (vertical opening width) of the gas nozzle 15 exceeds the above range, the gas sprayed onto the solvent absorber 6 is likely to diffuse, and the effect of improving the suction efficiency of the ink solvent by the suction nozzle 14 is obtained. May be difficult. Further, if the slit interval (longitudinal opening width) is less than the above range, the area to which the gas is blown becomes very narrow, so that it is difficult to obtain the effect of improving the suction removal efficiency of the ink solvent by the suction nozzle 14. .

Moreover, it is preferable that the space | interval between the surface of the solvent absorber 6 and the opening part of the gas nozzle 15 is made as narrow as possible from a viewpoint of improving the suction efficiency of the ink solvent by the suction nozzle 14. On the other hand, if it falls below the above range, the solvent absorber 6 may be damaged by contact with the gas nozzle 15.
For example, the ultrasonic transducer 16 is disposed on the upstream side in the rotation direction of the solvent absorber 6 with respect to the position facing the suction nozzle 14 with respect to the solvent absorber 6 or the position opposed to the position. The absorption efficiency of the ink solvent from the solvent absorber 6 can be further improved by sucking with the suction nozzle 14 while applying ultrasonic vibration from the ultrasonic vibrator 16 to the solvent absorber 6. .

As the ultrasonic vibrator 16, various ultrasonic vibrators such as piezoelectric ceramics can be used. Moreover, what is necessary is just to set the frequency of the ultrasonic vibration provided to the solvent absorber 6 suitably according to the kind of the forming material of the solvent absorber 6, and the ink solvent, for example, it sets in the range of 1-5 MHz.
The ultrasonic transducer 16 is preferably in close contact with the back surface of the blanket 2 of the solvent absorber 6 (surface on the side opposite to the contact surface side of the solvent absorber 6 with the blanket 2). In addition, when ultrasonic vibration is applied to the solvent absorber 6 by the ultrasonic vibrator 16, the moving speed of the solvent absorber 6 is, for example, 3 to 60 mm / s, and preferably 5 to 30 mm / s. .

If the above printing method is carried out in the printing apparatus 1 described above, it is possible to suppress the ink solvent absorption effect from the blanket 2 by the solvent absorber 6 from decreasing over time, and to improve printing productivity in high-precision printing. Can be made.
FIG. 3 is a schematic apparatus configuration diagram showing another embodiment of the printing apparatus of the present invention.
In FIG. 3, the printing device 17 includes a blanket 2, a blanket cylinder 3 that fixes the blanket 2 to the surface, an intaglio (not shown) as a printing plate, a substrate 5 as a printing medium, and an outer peripheral surface of the blanket 2. And a vacuum chamber 18 as second solvent suction / removal means for sucking and removing the ink solvent from the solvent absorber 6 in a non-contact state. The blanket 2, the blanket cylinder 3, the intaglio, the substrate 5, and the solvent absorber 6 are the same as those in the above-described embodiment.

  The vacuum chamber 18 is a member for providing an internal space that is decompressed and maintained at a high vacuum level. Referring to FIGS. 3, 4 (a) and 4 (b), this vacuum chamber 18 accommodates the solvent absorber 6 in a state of being stretched over the rollers 11, 12, 13. A triangular prism-shaped sheath portion 19 and a lid portion 20 for sealing and sealing the open end of the sheath portion 19 are provided. Further, the sheath portion 19 includes a packing 22 for improving the adhesion with the lid portion 20 at the flange portion 21 at the opening end, and the inside of the sheath portion 19 is a solvent partitioned by the inner surface 23. An accommodating portion for the absorber 6 is provided. On the other hand, referring to FIG. 3 and FIG. 4 (c), the lid 20 includes a suction cylinder 24, and the lid 20 side opening end of the suction cylinder 24 accommodates the sheath 19. It communicates with the department. Further, a vacuum pump (not shown) is connected to the suction cylinder portion 24 outside the vacuum chamber 18.

  The vacuum chamber 18 is fixed to a slide type air cylinder 25. The air cylinder 25 is in a vacuum suction state (state indicated by a dotted line in FIG. 3) in which the solvent absorber 6 is housed in the housing portion in a state where the solvent absorber 6 is stretched over the rollers 11, 12, 13, and the solvent absorber 6. The axial direction of each of the rollers 11 to 13 that support the solvent absorber 6 so as to be able to take two states, that is, a vacuum suction process that is uncovered from the housing portion (a state indicated by a solid line in FIG. 3). The vacuum chamber 18 is held so as to be able to move in parallel.

In the printing method using the printing apparatus 17 according to this embodiment, the solvent of the ink sucked by the solvent absorber 6 is sucked in a non-contact state by the second solvent suction removing means (vacuum chamber 18) and removed. A removal step is provided.
In this solvent suction removal step, first, the vacuum chamber 18 is disposed so as to be in the above-described vacuum suction state so as to cover the solvent absorber 6. At this time, the sheath portion 19 and the lid portion 20 of the vacuum chamber 18 are brought into close contact with each other with the packing 22 attached to the flange portion 21 of the sheath portion 19 interposed therebetween. Next, the inside of the housing part of the vacuum chamber 18 is sucked by a vacuum pump (not shown) attached to the suction cylinder part 24. Thereby, the inside of the accommodating part of the vacuum chamber 18 becomes a negative pressure, and the ink solvent in the solvent absorber 6 is sucked and removed from the solvent absorber 6.

The degree of vacuum in the vacuum chamber 18 is set to be −5 kPa (G) or less, preferably −10 kPa (G) or less, for example, on the basis of gauge pressure. Moreover, the time of the solvent suction removal process by the vacuum chamber 18 is 3 to 60 seconds, for example, Preferably, it is 5 to 30 seconds.
If the above printing method is carried out in the printing device 17, it is possible to suppress the ink solvent absorption effect from the blanket 2 by the solvent absorber 6 from decreasing over time, and to improve the printing productivity in high-precision printing. Can be made.

Figure 5 is a schematic system configuration diagram showing still another embodiment of the printing device.
In FIG. 5, the printing device 26 includes a blanket 2, a blanket cylinder 3 that fixes the blanket 2 to the surface, an intaglio plate 4 as a printing plate, a substrate 5 as a printing medium, and an outer peripheral surface of the blanket 2. An endless belt 27 serving as a solvent absorber that contacts and absorbs the ink solvent, and a hot air nozzle 28 serving as a heating unit that heats the endless belt 27 to evaporate and remove the ink solvent are provided. The blanket 2, the blanket cylinder 3, the intaglio 4 and the substrate 5 are the same as those in the above embodiment.

  In FIG. 5, the solvent absorber is an endless belt 27 that is in contact with the outer peripheral surface of the blanket 2, a roller that spans and supports the endless belt 27, and a chiller that cools the endless belt. Two driven rollers 29 and 30 with a chiller and one tension roller 31 with a chiller are also used. This solvent absorber is the same as the solvent absorber 6 in the above-described embodiment except that the rollers 29 to 31 are also used as chillers.

It does not specifically limit as a refrigerant | coolant used for each said rollers 29-31, The thing similar to the refrigerant | coolant used for various chillers is mentioned.
The hot air nozzle 28 is disposed so as to face the contact surface (surface) of the endless belt 27 of the solvent absorber with the blanket 2 with a space therebetween. The hot air nozzle 28 is a slit nozzle that is opened in an elongated rectangular shape along the axial direction of the rollers 11 to 13 that support the solvent absorber 6.

The printing method using the printing apparatus 26 according to the above embodiment includes a solvent evaporation removing step in which the solvent of the ink sucked by the endless belt 27 of the solvent absorber is evaporated and removed by the hot air nozzle 28 as a heating means. And a cooling step for cooling the endless belt 27 after the solvent evaporation removing step.
In this solvent evaporation and removal step, first, a state (separated state) in which the two chiller driven rollers 29 and 30 that support the endless belt 27 are spaced apart from the outer peripheral surface of the blanket 2. To do. Next, the endless belt 27 is rotated by two driven rollers 29 and 30 with a chiller and one tension roller 31 with a chiller, and hot air is jetted from the hot air nozzle 28 onto the surface of the endless belt 27. Thereby, the surface of the endless belt 27 is heated, and the ink solvent in the endless belt 27 evaporates. Thereafter, in order to cool the surface temperature of the endless belt 27, the endless belt 27 and the rollers with chillers 29 to 31 are brought into contact with each other.

The surface temperature of the endless belt 27 is set to be, for example, within ± 0.5 ° C., preferably within ± 0.3 ° C. before and after the solvent evaporation and removal process, in order not to affect the printing accuracy. To do.
In the solvent evaporation removal step, the moving speed of the endless belt 27 is, for example, 3 to 60 mm / s, preferably 5 to 30 mm / s. The temperature of the hot air ejected from the hot air nozzle 28 is, for example, 100 to 150 ° C., preferably 120 when the ink solvent is a glycol ester having a relatively high boiling point (about 200 to 280 ° C.). ˜140 ° C. Moreover, the jet time of the warm air by the warm air nozzle 28 is, for example, 20 to 60 seconds, and preferably 30 to 50 seconds.

If the above printing method is carried out in the printing device 26, it is possible to suppress the effect of absorbing the ink solvent from the blanket 2 by the endless belt 27 of the solvent absorber from decreasing with time, and production of printing in high-precision printing. Can be improved.
The printing apparatus and the printing method using the printing apparatus are suitable for high-precision printing, such as printing formation of a color filter layer and a black matrix in a liquid crystal color filter, and printing formation of an electrode substrate 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 “Vylonal (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. A stripe pattern 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 was formed on the surface of the substrate.

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.

  In Examples 1 and 2 and Comparative Example 1, the solvent absorber 6 includes a polyethylene terephthalate base material 9 (width 450 mm, length 10 m, thickness 100 μm) and a urethane resin (trade name “KU-” on the surface). 7002 ", Hitachi Chemical Co., Ltd.) was used, and a laminate including a solvent absorbing layer 8 that 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 8 was 0.07 MPa.

In Example 3, the same endless belt 27 as the solvent absorber as the solvent absorber 6 in Examples 1 and 2 and Comparative Example 1 was used. In Example 3, a roller with a chiller that can be cooled with a refrigerant from the inside of the roller was used as the two driven rollers 29 and 30 and the one tension roller 31 for suspending and supporting the endless belt 27.
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 Examples 1 to 3 and Comparative Example 1 below, the solvent blotting process was performed each time a series of printing processes including an ink carrying process and a printing process 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.

Further, in Examples 1 and 2 below, the solvent suction removal process was performed each time a series of printing processes including an ink carrying process and a printing process were performed once, similarly to the solvent sucking process. In Example 3 below, the solvent evaporation removal process was performed each time a series of printing processes including an ink carrying process and a printing process were performed once, as in the solvent blotting process.
Example 1
The solvent suction removal step of the printing test was performed by sucking with the suction nozzle 14 while moving the solvent absorber 6 at a speed of 30 mm / s (see FIG. 1).

Example 2
The solvent suction removal step of the printing test was performed by covering the entire solvent absorber 6 with the vacuum chamber 18 and maintaining the vacuum degree in the vacuum chamber 18 at −5 kPa (G) on the basis of the gauge pressure for a predetermined time. (See FIG. 3).
Example 3
The solvent evaporation removal step of the printing test was performed by injecting hot air of 120 ° C. from the hot air nozzle 28 while moving the endless belt 27 of the solvent absorber at a speed of 5 mm / s (see FIG. 5). . The endless belt 27 was cooled by rollers 29 to 31 with chillers, and the change in the surface temperature of the endless belt 27 before and after the solvent evaporation removal process was adjusted to be within ± 0.3 ° C.

Comparative Example 1
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 could be suppressed within ± 3 μm, and the variation in the line width of the stripe pattern in the substrate 5 could be suppressed within ± 3 μm. The time required for suction by the suction nozzle 14 was 20 seconds on average.

In Example 2, 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 ± 4 μm. The time required for the solvent suction removal process in the vacuum chamber 18 was 30 seconds on average.
Further, in Example 3, 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 ± 4 μm. Moreover, the hot air injection time from the hot air nozzle 28 was 30 seconds on average.

The results of Examples 1 to 3 described above 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, an imperfect transfer of ink from the blanket 2 to the substrate 5 occurred as soon as the printed line width was less than 70 μm. In Comparative Example 1, the printing process was stopped when 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 absorber. It is a schematic apparatus block diagram which shows other embodiment of the printing apparatus of this invention. (A) is a front view of the sheath part 19 of the vacuum chamber 18 shown in FIG. 3, (b) is a right side view, and (c) is a 20 left side view of the lid part of the vacuum chamber 18. It is a further schematic device arrangement view showing another embodiment of a printing apparatus. It is the graph which showed transition of the line width of the printing pattern in an example and a comparative example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Printing device, 2 Blanket, 3 Blanket cylinder, 6 Solvent absorber, 7 First solvent suction removal means, 14 Suction nozzle, 17 Printing device, 18 Vacuum chamber (second solvent suction removal means), 26 Endless belt ( Solvent absorber).

Claims (3)

A blanket for carrying on the surface the ink to be transferred to the substrate;
A blanket cylinder for fixing the blanket to the surface;
A solvent absorber for sucking out the solvent of the ink that has oozed into the blanket by contact with the outer peripheral surface of the blanket;
A solvent suction removal means for sucking and removing the solvent of the ink sucked by the solvent absorber from the solvent absorber in a non-contact state ;
The blanket is movable between an ink carrying position for carrying ink on its surface, a printing position for printing the carried ink on a printing medium, and a sucking position where the solvent of the soaked ink is sucked off. Has been placed,
The solvent absorber is formed in an endless belt shape that is stretched between two driven rollers and a tension roller arranged so that an axis thereof is parallel to the rotation axis of the blanket cylinder. The driven roller is disposed so as to be in contact with each other with the solvent absorber interposed between the separated state in which the driven roller is spaced apart from the outer peripheral surface of the blanket and the outer peripheral surface of the blanket. It is arranged so as to be able to move in parallel with the blanket cylinder so that the two states can be taken into contact with each other, thereby abutting the blanket at the sucking position to remove the solvent of ink that has oozed into the blanket. Is to suck up,
When the two driven rollers are in the separated state, the solvent absorbing means is spaced from the contact surface of the solvent absorber with the blanket and is disposed opposite the solvent absorber. It characterized the erased, the printing apparatus. A blanket for carrying on the surface the ink to be transferred to the substrate;
A blanket cylinder for fixing the blanket to the surface;
A solvent absorber for sucking out the solvent of the ink that has oozed into the blanket by contact with the outer peripheral surface of the blanket;
A solvent suction removal means for sucking and removing the solvent of the ink sucked by the solvent absorber from the solvent absorber in a non-contact state;
The blanket is movable between an ink carrying position for carrying ink on its surface, a printing position for printing the carried ink on a printing medium, and a sucking position where the solvent of the soaked ink is sucked off. Has been placed,
The solvent absorber is formed in an endless belt shape that is stretched between two driven rollers and a tension roller arranged so that an axis thereof is parallel to the rotation axis of the blanket cylinder. The driven roller is disposed so as to be in contact with each other with the solvent absorber interposed between the separated state in which the driven roller is spaced apart from the outer peripheral surface of the blanket and the outer peripheral surface of the blanket. It is arranged so as to be able to move in parallel with the blanket cylinder so that the two states can be taken into contact with each other, thereby abutting the blanket at the sucking position to remove the solvent of ink that has oozed into the blanket. Is to suck up,
The solvent removed by suction means, said solvent absorber and the sheath portion for accommodating at over passed state to the two driven rollers and the tension roller, seals the open end of the sheath portion, for sealing and a lid portion, when said two driven rollers became the separated state, the solvent absorber accommodated in the sheath portion, vacuum chamber is sealed and sucking the sheath portion by the lid and characterized in that, printing device. A printing method using a printing apparatus according to claim 1 or 2, a printing step of printing the ink carrying step of carrying the ink to the surface of the blanket, the supported ink to the surface of the blanket to the printing substrate The solvent absorbing step of sucking the solvent of the ink soaking into the blanket with the solvent absorber, and the solvent of the ink sucked into the solvent absorber is sucked and removed in a non-contact state by the solvent suction removing means. And a solvent suction removing step.

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