JP3298970B2 - Offset printing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an offset printing apparatus, and more particularly to an offset printing apparatus suitable for producing a color filter for an LCD by transferring a pattern on an intaglio onto a work through a blanket cylinder. Related to the device.

[0002]

2. Description of the Related Art Hitherto, a color filter for an LCD has been manufactured by continuously and repeatedly printing a fine pattern of R, G, and B on a transparent substrate made of glass. As a method of forming the image portion of the LCD color filter, a lithographic offset printing method or an intaglio offset printing method is frequently used because of high accuracy and low cost. Here, straightness and positional accuracy of each of the R, G, and B patterns are required, and pattern matching is required when R, G, and B inks are sequentially printed.

As a conventional offset printing apparatus of this type, there is a type shown in FIG . That is, the conventional offset printing apparatus M ₀ has a base 100, and a stage 101 is supported on the base 100. Above the center of the stage 101, a blanket cylinder 102 attached to a support frame 107 is provided.
The blanket cylinder 102 moves back and forth in accordance with the rotation of No. 3. A plate surface plate 120 for mounting the intaglio P ₀ is on the stage 101, a work platen 121 for placing a workpiece W ₀ made of a glass plate is arranged. A guide rail 104 is provided on the upper side of the base 100, and a slider 105 slides along the guide rail 104, and the slider 105 is fixed to the support frame 107. The lower portion of the support frame 107 is engaged with a ball screw 106, and the ball screw 106 rotates when the rotation of the motor 103 is transmitted via the belt B.

A rack 109 and a bearer 110 are provided on both left and right sides of the stage 101.
9 and a bearer 110, respectively, a pinion 108 and a bearer 111 on the left and right of the blanket cylinder 102, respectively.
Is provided. Then, with the bearer 110 and the bearer 111 in contact with each other, the rack 109 and the pinion 10
8 meshes, yet in engagement height between the rack 109 and the pinion 108 becomes the same as the height of the intaglio P ₀ and the workpiece W _0, blanket cylinder 102 is adapted to reciprocate.

[0005]

However, in the conventional offset printing apparatus M ₀ , the blanket cylinder 102 reciprocates on the stage 101, and the blanket moving type moving body (blanket cylinder) is used. (L is the length of the moving body in the printing direction, D is the length of the moving body in the printing vertical direction, see FIG. 5 ) is about 0.5, which is a major factor in the printing accuracy of this type of offset printing apparatus. Yawing becomes worse. Generally, the L / D of the moving object needs to be about 1.5 in order to maintain good yawing, and if L / D <1.5, the yawing becomes worse. In addition, the center of gravity of the moving body becomes high when considering the sliding surface (linear guide surface, bearer surface) as a reference, which causes poor positioning accuracy.

The conventional offset printing apparatus M ₀ is
The blanket cylinder 102 is rotated and moved by the engagement between the rack 109 and the pinion 108. Therefore, the synchronization accuracy of the rotation and the movement largely depends on the pitch and the tooth profile accuracy of the gears, and is affected by the backlash, so that an expensive gear is required to increase the synchronization accuracy.

Further, the conventional offset printing apparatus M ₀ is
The vertical movement of the blanket cylinder is supported by the contact of a mechanically fixed bearer. Therefore, it is difficult to maintain uniform contact over the entire length of the blanket cylinder and to follow variations in the thickness of the work or undulations on the work surface.

In view of the above, the present invention has been made in view of the above circumstances, and has been developed from a printing plate (intaglio) to a printing medium (work).
It is an object of the present invention to provide an offset printing apparatus capable of performing printing with high positioning accuracy repeatedly through a blanket cylinder.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a base, a stage reciprocating on the base, and an intaglio mounting plate provided on the stage, the position of which is adjustable. A platen, a work surface plate provided on the stage for position adjustment, and a blanket cylinder provided at a position corresponding to the stage above the base; and a stage motor for moving the stage. When the blanket cylinder motor for rotating the blanket cylinder, the stage motor and the blanket cylinder motor controlled individually, intaglio Inn
Blanket rather than the speed at which
Increase the speed at which the ink on the
In terms of speed, the speed of the blanket cylinder and the speed of the stage
It was constructed and a control device which Ru synchronize.

The stage motor and the blanket cylinder motor each include a pulse motor, and the control device controls the stage motor and the blanket cylinder motor in a semi-closed control system.

Further, the offset printing apparatus detects an alignment mark between the work and the intaglio plate, and moves the alignment between the work surface plate for placing the work and the plate surface for placing the intaglio. It was configured with the device.

Further, the blanket cylinder is provided with a blanket cylinder height position adjusting device for automatically changing the height position of the blanket cylinder in accordance with a change in the height of the work upper surface.

[0013] Further, the apparatus is provided with a dispenser device for supplying ink to the intaglio, and a doctor device for filling the image portion of the intaglio with the supplied ink and scraping excess ink.

[0014]

[Function] A glass plate-shaped work and an intaglio plate are fixed to a work surface plate and a plate surface plate on a stage, respectively. Ink is supplied on the intaglio plate by a dispenser device, and supplied by a doctor device while moving the stage. Fill the ink in the intaglio image area, scrape off excess ink, and transfer the ink in the intaglio image area to the blanket on the peripheral surface of the blanket cylinder while moving the stage and rotating the blanket cylinder. Then, the pattern on the intaglio transferred to the blanket cylinder is transferred onto the work while continuously moving the stage.

At this time, the rotation control of the blanket cylinder is performed by a pulse motor of the blanket cylinder, and the reciprocation of the stage is performed by a pulse motor of the stage. The control device controls the rotation of the blanket cylinder motor and the stage motor separately, and the table movement and the blanket cylinder rotation are synchronized when transferring from the intaglio to the blanket cylinder and from the blanket cylinder to the work. . But concave
It is faster than the speed at which the plate ink is transferred to the blanket cylinder.
Increases the speed at which the ink on the racket cylinder is transferred to the work
Comb.

As described above, the L / D (see FIG. 5B) becomes about 3 by moving the table (stage) instead of printing by moving the blanket, which is a major factor in the accuracy of the printing apparatus. Yawing is improved. In the case of a table (stage) movable type, the height of the center of gravity of the movable body (in this case, the stage) can be made substantially the same as the height of the sliding surface between the stage and the linear guide.
The positioning accuracy can be improved. Also, intaglio
The blank speed is higher than the speed at which ink is transferred to the blanket cylinder.
Increase the speed at which ink on the cylinder is transferred to the workpiece
As a result, the ink of the intaglio is properly transferred onto the work.

In addition, by separately controlling the rotation of the blanket and the movement of the table having the platen and the work platen according to the present invention, the above-mentioned causes of the inaccuracy of the rack and gears can be eliminated. When a slight change in the actual blanket cylinder diameter occurs due to a change in the indentation amount, a change in the blanket thickness, etc., the separate control of the blanket cylinder and the table of the present invention enables a high-precision synchronization accuracy that follows the small change. Can be obtained.

In addition, even if there is variation in the thickness of the work or undulation of the work surface, the blanket cylinder moves up and down according to the height of the work surface, and the pushing amount can be made uniform over the entire length of the blanket. Transfer at a constant pressure becomes possible.

Further, a plate surface for adjusting the position of the intaglio placed on the stage, which is optically detected to detect the alignment mark positions of the plate and the work, so that the plate and the work are at predetermined positions, By moving the work surface plate for work placement on the stage, the work position of which is adjustable,
The relative position of the plate and the work for each printing is the same, for example, L
R, G, B patterns of a color filter having good relative positions of the black matrix and R, G, B formed in advance on the work required for the CD color filter and good matching of each color pattern are continuously and stably formed. can do.

[0020]

An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the offset printing apparatus M ₁ of the present invention has a base 1 having a rectangular, on the base 1 is the stage 2 is provided to be reciprocated. A blanket cylinder 3 is rotatably provided above the center of the base 1 in the longitudinal direction. Wherein on the stage 2 is provided plate surface plate 6 for mounting the intaglio P ₁ made of a glass plate, in parallel with the plate surface plate 6, the workpiece W ₁ is a glass plate
A work surface plate 7 for placing the work is provided. Incidentally, the two plate 6,7 is provided with a large number of small holes on the surface, so that sucks and holds the intaglio P ₁ and workpiece W ₁ on the platen 6 by a vacuum pull.

The intaglio P ₁ is adjacent to the blanket cylinder 3.
Of the ink supplied above, a doctor device 26 for wiping excess ink and filling the image portion of the intaglio P1 with ink is provided so as to be vertically movable, and the intaglio device is provided adjacent to the doctor device 26. vertically movable dispenser 27 for supplying ink is provided on P _1. The work W is disposed adjacent to the dispenser 27.
₁ and the intaglio P ₁
Alignment apparatus 4 to force the relative positional relationship between an alignment mark formed on said workpiece W ₁ and intaglio P ₁ detected optically are provided respectively.

Both ends of the blanket cylinder 3 are supported by a constant pressure device 11 for performing transfer at a predetermined pressure, and the height position of the blanket cylinder 3 is adjusted by the constant pressure device 11.

A stage motor 12 is provided on an end face of the base 1.
A ball screw 13 is connected to the stage motor 12, and the ball screw 13 is screwed to engaging members 14, 14 provided on the back side of the stage 2. A linear guide 1 is provided on both upper surfaces of the base 1.
5 and 15 are disposed in the longitudinal direction.
A sliding piece 1 provided on the lower left and right sides of the stage 2
6, 16 are slidably engaged. When the stage motor 12 rotates, the stage 2 slides left and right.

A blanket motor 17 is provided on one side of the blanket cylinder 3 via a transmission 18.
The blanket cylinder 3 is rotated by the blanket motor 17. As shown in FIG. 3, the blanket motor 17 and the stage motor 12
And is individually controlled by the control device 40. Here, the reciprocating motion of the stage 2 and the rotational position of the blanket cylinder 3 need to be synchronized. However, if the stage motor 12 and the blanket motor 17 are individually controlled by the control device 40 as described above, the stage 2 and the rotation of the blanket cylinder 3 can be accurately synchronized. The movement of the stage 2 and the rotation position of the blanket cylinder 3 are synchronized by a so-called semi-closed control in which a difference between a target command value and a rotation amount of the motor is obtained and the difference is controlled to be zero. ing.

The blanket cylinder 3 is provided with the constant pressure device 1
1 supported. That is, the constant pressure device 11 has a rotating shaft 23 at the left and right ends of the blanket cylinder 3, and the rotating shaft 23 is supported by the air cylinder 20 via the support plate 22 in a floating manner. The constant pressure device 11 is provided on the left and right sides of the blanket cylinder 3, but only one side is shown in the figure. The air cylinder 20 is supported on a support frame 21 fixed to the side surface of the base 1, and the supply of compressed air to the air cylinder 20 is controlled by the control device 40. A positioning rod 24 is provided below the support plate 22, and the positioning rod 24 sets a reference height position of the blanket cylinder 3. The support plate 22 is provided on the base 1.
The frame F is formed so as to be able to move up and down on a frame F protrudingly formed on the side plate.

When the blanket cylinder 3 is floating supported by the constant pressure device 11 in this manner, as shown in FIG. 2, the surface S of the work W ₁ or the intaglio P ₁ undulates, or the work W ₁ or the intaglio P _When the thicknesses of the blanket cylinders ₁ are different, the blanket cylinder 3 comes in contact with the blanket cylinder 3 while moving up and down in accordance with the height position of the surface S. made uniform, contact with the workpiece W ₁ or intaglio P ₁ becomes uniform, it is possible to pressure printing enables stable high-precision printing.

[0027] Incidentally, the alignment apparatus optical system 4a which includes a CCD camera arranged on the left and right 4 consists 4b, these optical devices 4a, an alignment mark of the work W ₁ or intaglio P ₁ as 4b have been described above Each of them is detected by two CCD cameras to determine the mutual positional relationship. As shown in FIG. 3, the platen plate 6 and the work platen 7 are pulse motors 4 for X coordinate, Y coordinate and angle, respectively.
1, 42 and 43 are driven and adjusted.

Next, the operation of the offset printing machine M ₁ of the present invention will be described with reference to FIG. FIG. 4A shows an initial state, in which an intaglio P ₁ is fixed on the platen 6 by suction, and a work W ₁ is fixed on the work base 7 by suction. At this time, the blanket cylinder 3, the doctor device 26 and the dispenser 27 are both lifted. Next, in this state, the stage motor 12 is driven, and the stage 2 moves to the left in the figure as shown in FIG. On this occasion,
The work W ₁ and the intaglio P ₁ are aligned by the alignment device 4.
Is adjusted.

Next, as shown in FIG.
The stage motor 2 moves to the right side in the figure as the dimotor 12 rotates in the reverse direction.
You. At this time, the dispenser 27 first descends and
Intaglio P₁The ink is supplied on the top and this ink supply ends
Then, the dispenser 27 rises, and then the stage 2
Moves to the doctor ring start point, and the doctor device 26
Intaglio P₁Scraping off excess ink on the intaglio image area
Fill with ink. Intaglio P by the doctor device 26
₁When the above ink scraping is completed, the doctor device 26
Rises immediately and the work W₁Allow the passage of. Then figure
4 (D), the intaglio P₁Is a blanket torso
3, the blanket cylinder 3 descends and the intaglio P₁Up
Pattern on the blanket around the blanket cylinder 3
Transcribed. Next, as shown in FIG.
W₁Comes into contact with the blanket cylinder,
The pattern on the blanket on the surface is the work W₁Transcribed on
It is. After that, as shown in FIG.
Return to the reference position, and work W ₁Removed from work surface plate 7
It is stored. After one cycle like this,
New work W on work surface plate 7₁Is supplied as described above
A similar operation is performed.

In the above operation, the control device 40
, In FIG. 4 (C), (D) , in the case of transferring the ink on the intaglio plate P ₁ to the blanket cylinder 3 is relatively low speed driven to the blanket cylinder 3 and stage 2, the circumferential surface of the blanket cylinder 3 when transferring the pattern on the workpiece W ₁ is (FIG. 4 (E)), allowed to drive the stage 2 and blanket cylinder 3 at a relatively high speed. For example, 1 in the case of transferring a pattern from on the intaglio P ₁ to the blanket cylinder 3
7 mm / sec speed driven to the stage 2 and blanket cylinder 3, upon transfer to the upper work W ₁ is 100
Blanket cylinder 3 and stage 2 at a speed of mm / sec
Drive.

The ink on the blanket cylinder 3 by adjusting the speed in this way is found to be completely transferred onto the workpiece W _1. This is considered to be due to the change in the strength of the ink-blanket interface, the ink-glass interface, or the transfer rate of the ink strength.

A conventional offset printing apparatus (FIG. 5)
The following results were obtained by a comparison experiment between the present invention and the offset printing apparatus of the present invention (FIG. 1). Conventional offset printing apparatus blanket movement (for printing direction of 1200 mm) a) meandering amount 140 μm b) Yawing 50 seconds c) printing pressure direction displacement 60 μm d) Pitching 20 seconds e) blanket position accuracy ± 40 μm Offset printing apparatus of the present invention a) Table repetitive positioning (corresponding to the above meandering amount) ± 3.32 μm b) Yawing 1.72 seconds c) Table vertical movement (corresponding to the above printing pressure direction displacement) 2.92 μm d) Straightness (to the above blanket position accuracy) 3.72 μm

[0033]

The present invention is configured as described above.
The accuracy of the moving table, such as the meandering amount, positioning accuracy, yawing, etc., is improved, and the blanket rotation and printing direction movement synchronization accuracy required for the offset printing device, and the relative position accuracy between the plate and the work are improved. Can also be achieved. Further, the pressing amount at the time of transfer of the blanket cylinder to the work is made uniform, so that constant pressure printing becomes possible. Also,
Than the speed at which the intaglio ink is transferred to the blanket cylinder.
The speed at which the ink on the blanket cylinder is transferred to the work
Enlarged, intaglio ink is transferred to the workpiece properly
I do. As a result, for example, when printing in three colors of R, G, and B, a high-precision, high-quality LCD color filter having a good relative position with respect to a black matrix formed in advance on a work and good matching between the colors. Is produced.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of an embodiment of an offset printing press according to the present invention.

FIG. 2 is an explanatory diagram showing a detailed state of constant-pressure printing in the embodiment.

FIG. 3 is a schematic configuration diagram of a control device of the embodiment.

FIG. 4 is an operation explanatory view of the embodiment.

FIG. 5 is a perspective view of a conventional offset printing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base 2 ... Stage 3 ... Blanket cylinder 4 ... Alignment device 6 ... Plate surface plate 7 ... Work surface plate 11 ... Constant pressure device (blanket cylinder height position adjustment device) 12 ... Stage motor 17 ... Blanket cylinder motor 26 ... Doctor Device 27 ... Dispenser device 40 ... Control device

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) B41F 33/08 B41F 3/20 B41F 17/14 B41F 33/14

Claims (5)

(57) [Claims] 1. A base, a stage which reciprocates on the base, a platen for mounting an intaglio mounted on the stage, the position of which can be adjusted, and a position adjustable, which is provided on the stage. A work surface plate for mounting a work, a blanket cylinder provided at a position corresponding to the stage above the base, a stage motor for moving the stage, a blanket cylinder motor for rotating the blanket cylinder, and the stage the motor and the blanket cylinder motor controlled individually, intaglio Lee
Blanket rather than the speed at which ink is transferred to the blanket cylinder.
Increase the speed at which the ink on the cylinder is transferred to the work,
Blanket cylinder speed and stage speed at each speed
Offset printing apparatus characterized by and a control device which Ru synchronize and. 2. The apparatus according to claim 1, wherein the stage motor and the blanket cylinder motor each include a pulse motor, and the control device controls the stage motor and the blanket cylinder motor in a semi-closed control system. Offset printing device. 3. The offset printing apparatus detects an alignment mark between a work and an intaglio, and moves and aligns the relative position between the work surface plate for mounting the work and the plate surface for mounting the intaglio. 3. The offset printing apparatus according to claim 1, further comprising an apparatus. 4. The apparatus according to claim 1, wherein said blanket cylinder includes a blanket cylinder height position adjusting device for automatically changing a height position of said blanket cylinder in accordance with a change in height of a work upper surface. An offset printing apparatus according to any one of claims 1 to 3. 5. A dispenser device for supplying ink to the intaglio, and a doctor device for filling the image portion of the intaglio with the supplied ink and scraping excess ink. An offset printing apparatus according to any one of claims 1 to 4.